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1.
Past research has demonstrated clear gender differences in reported mate selection criteria. Compared to women, men place more importance on physical attractiveness and women place more importance than men do on the earning capacity of a potential mate. These gender differences have been explained using both sociobiological propositions and differences in the relative economic power of men and women. The present study tested the structural powerlessness hypothesis as an explanation for women's greater emphasis on the earning capacity of a potential spouse. Samples of college students (N = 997) and community members (N = 282) were asked to report expected personal income and to rate the importance of listed characteristics in a potential mate. Consistent with past research, men placed more emphasis on the item Good Looks, whereas women placed more importance on the item Good Financial Prospect. Contrary to the structural powerless model, women's expected income was positively related to ratings of the importance of a potential mate's earning capacity in the college sample and was unrelated to women's ratings of the item Good Financial Prospect in the community sample. Findings are discussed in terms of both evolutionary psychology and gender differences in access to financial resources.  相似文献   

2.
The purpose of this study was to analyze sex-related differences in spontaneous and evoked brain activity. The study included 11 women and 10 men aged between 18 and 27 years; the subjects were adapted to the conditions of electrophysiological experiment. Differences in spontaneous activity were estimated by EEG spectral characteristics in frequency ranges corresponding to θ, α, β1, β2, γ1, and γ2 rhythms at rest with the eyes open and closed. The differences in evoked activity were estimated by the parameters of evoked potentials (EP) recorded upon the presentation of different types of stimuli (images and words) and categories (“fruits” and “vessels”). Behavioral differences were estimated by the efficiency of stimuli recognition. No gender differences were observed in the efficiency of stimuli recognition (number of errors, time of reaction). In the EEG of male subjects at rest, fast frequencies (β and γ) were less marked than in the female subjects, which may indicate a higher level of activation of CNS structures in women. Regardless of stimuli type and category, the amplitude of EP components in men is lower than that in women, which may be caused by lower level of CNS activation. However, the difference in the latency of EP components depended on the type of stimuli used. During the recognition of visual images, the latency of earlier EP components (N1, P2) in men was longer mostly on back and/or right electrodes. The latencies of the later EP components (P3, N3) in male subjects were longer on the back electrodes and shorter on the front electrodes than those in female ones. During the recognition of words, the latency of P1, N1, P2 and N2 components in men were shorter on temporal and temporoparietal electrodes of the left hemisphere. This may indicate that visual image in men are perceived slower but comprehended faster than in women. On the other hand, verbal stimuli in men were perceived faster but comprehended slower than in women.  相似文献   

3.
Background: Men and women differ substantially in regard to degrees of insulin resistance, body composition, and energy balance. Adipose tissue distribution, in particular the presence of elevated visceral and hepatic adiposity, plays a central role in the development of insulin resistance and obesity-related complications.Objective: This review summarizes published data on gender differences in insulin resistance, body composition, and energy balance, to provide insight into novel gender-specific avenues of research as well as gender-tailored treatments of insulin resistance, visceral adiposity, and obesity.Methods: English-language articles were identified from searches of the PubMed database through November 2008, and by reviewing the references cited in these reports. Searches included combinations of the following terms: gender, sex, insulin resistance, body composition, energy balance, and hepatic adipose tissue.Results: For a given body mass index, men were reported to have more lean mass, women to have higher adiposity. Men were also found to have more visceral and hepatic adipose tissue, whereas women had more peripheral or subcutaneous adipose tissue. These differences, as well as differences in sex hormones and adipokines, may contribute to a more insulin-sensitive environment in women than in men. When normalized to kilograms of lean body mass, men and women had similar resting energy expenditure, but physical energy expenditure was more closely related to percent body fat in men than in women.Conclusion: Greater amounts of visceral and hepatic adipose tissue, in conjunction with the lack of a possible protective effect of estrogen, may be related to higher insulin resistance in men compared with women.  相似文献   

4.
《Gender Medicine》2008,5(1):24-35
Background: Men and women differ markedly with regard to their use of, and responses to, methamphetamine (MA) and related amphetamines. However, these gender differences oftentimes are given only a cursory consideration in the analyses of these MA effects.Objective: In this brief review, we summarize the data on gender differences in various parameters of MA use and responses. Such information on the pattern of male versus female differences in the use and responses to this psychostimulant can aid in tailoring gender-dependent treatment strategies.Methods: English-language articles were identified from MEDLINE as well as from reference lists of identified articles for the years 1966 to 2007. Search terms included various combinations of men/male, women/female, methamphetamine, and gender/sex differences. Only studies with human subjects were reviewed.Results: Women tend to begin MA use at earlier ages, appear more dependent on MA, but also respond better to treatment than do men. MA use appears to be associated with depression in women, and women seem more committed to MA, whereas men are more likely to use other drugs in the absence of access to MA. Female MA abusers had both larger volumes within the corpus callosum and more hyperperfused regions in the parietal and occipital areas of the brain, along with more genetic alterations but less MA-induced toxicity. Amphetamine-stimulated dopamine release was greater in men.Conclusions: When considered in total, women seem more dependent on and committed to MA but show diminished (amphetamine-stimulated) dopamine responses and a decreased degree of toxicity, as indicated by a lower incidence of emergency department-related deaths involving MA. A pervasive comorbidity of depression or depression-related characteristics were present in women MA users, suggesting that MA may serve as a type of self-medication for their depression. These findings not only highlight the need for consideration of gender when assessing MA use, but also can serve to direct efforts at prevention and treatment programs that address the specific needs of men and women.  相似文献   

5.
It has often been speculated, and some evidence suggests, that men and women differ in the elicitation of jealousy: Men appear to be more likely than women to become upset over threats to sexual exclusivity; whereas women are more likely than men to react negatively to potential loss of partner time and attention. Both adaptionist and traditional social learning theories have been used to explain these apparent gender differences. In the present article we outline both explanations and review the relevant psychological literature on gender differences in the elicitation of jealousy. We propose that the difference in men's and women's psychological mechanisms for elicitation of jealousy is best characterized (at least in this culture) as a greater sensitivity among men to cues indicative of possible sexual infidelity rather than greater emotional upset in response to the occurence of extradyadic sex on the part of one's mate. We also provide data testing a traditional social learning explanation for the elicitation of jealousy. Results of a survey administered to college students (N = 223) demonstrate the subtle nature of gender differences in the elicitation of jealousy within this culture. Men and women were most likely to differ (in the hypothesized directions) when items pertained to concern over a partner's potential extradyadic sex rather than to reactions to sexual infidelity that is suspected to have already occurred. Although men reported placing more value on sexual activity within dating relationships and women reported placing more value on emotional intimacy, these ratings of relationship rewards did not explain the gender differences in reported jealousy. Results failed to support a traditional social learning explanation of jealousy and are discussed with regard to evolutionary theory and directions for future research.  相似文献   

6.
Background: Women are especially vulnerable to HIV infection because of biological, social, cultural, and economic factors. In Brazil, AIDS was initially seen predominantly in homosexual men, but the epidemic gradually reached a gender balance as increasing numbers of women became infected with HIV.Objective: The aim of the present study was to identify the clinical and epidemiologic characteristics of hospitalized patients with HIV/AIDS of both sexes and compare the differences between them.Methods: This epidemiologic cross-sectional study evaluated gender differences in demographic, social, clinical, and epidemiologic characteristics of patients diagnosed with HIV/AIDS who were admitted for any reason to the Public Hospital of the Medical School of the Federal University of Triângulo Mineiro, Uberaba, Minas Gerais State, Brazil.Results: A total of 363 patients were included in the analysis, with a male/female ratio of 1.1:1.0. Forty-one percent of women were pregnant. Mean age at hospitalization and duration of hospitalization were significantly greater among men (P<0.05). Men and nonpregnant women were admitted because of infection significantly more often than were pregnant women (P<0.05). Significantly more single men who reported homosexual, bisexual, or heterosexual behavior associated with drug use were admitted compared with women (P<0.05). Women admitted for treatment were significantly more likely than men to be employed (P<0.05). Adherence to antiretroviral treatment and T CD4+ lymphocyte count indicated important differences between the sexes, with better parameters observed among nonpregnant and pregnant women compared with men.Conclusions: In the present study, women with HIV/AIDS who were admitted to the hospital for any reason were in better clinical condition compared with men. This observation may be partially explained by the proportion of pregnant women in the study population. These findings suggest that future studies should examine pregnant women with HIV/AIDS as a separate population group to avoid bias in analysis.  相似文献   

7.
8.
Sexual dimorphism in physical appearance may be an important cue in both intra- and intersex competition. Recently, the facial width-to-height ratio (fWHR) has been proposed as a novel sexually dimorphic morphologic measure, with men suggested to have a higher fWHR than women. Currently, however, the status of fWHR as a sexually dimorphic trait is unclear. Here we tested for sexual dimorphism in fWHR, as well as in three additional, previously reported facial measures, in four (three Caucasian and one African) independent samples. In three of the four samples, no significant sex differences in fWHR were observed. In one sample, males showed a significantly lower (rather than higher) fWHR than females (this effect was no longer significant after controlling for body mass index). By contrast, significant and large sex differences were observed in all four samples for each of the three previously validated facial metrics, namely, (a) lower face/face height, (b) cheekbone prominence, and (c) face width/lower face height. These results provide strong evidence against the claim that fWHR, at least as measured from the surface of the face, is sexually dimorphic.  相似文献   

9.
《Gender Medicine》2007,4(3):266-273
Background: Cancer in individuals living with HIV and AIDS is a common source of morbidity and mortality, especially in the underdeveloped world. As antiretrovirals are distributed with greater equity across the globe, individuals with HIV and AIDS are living longer and developing malignancies, as opposed to other opportunistic infections.Objective: This article reviews the gender differences in studies of AIDS-associated cancers, examining factors related to transmission, treatment, and outcome.Methods: MEDLINE, PubMed, Ovid, conference proceedings, and abstract books were searched from 1983 onward for English-language publications and data on gender differences related to AIDS-associated cancers. Relevant trials were similarly reviewed. The search terms used were women or gender, cancer or tumor or malignancy, lymphoma or Kaposi, and HIV or AIDS.Results: We found that studies in established market economies have focused predominantly on men, although a wider view suggests that the rapidly growing rates of HIV infection among women should prompt specific oncologic challenges.Conclusion: Immunosuppression-induced malignancies in women, Kaposi sarcoma in particular, are likely to represent a global issue in the future. (Gend Med..  相似文献   

10.
Background: An increasing number of studies have reported differences in the pharmacokinetics and/or pharmacodynamics of antidepressants between women and men.Objectives: This article updates previously published literature describing sex differences in the pharmacokinetics and pharmacodynamics of antidepressants, and examines specific issues that face women with psychiatric illness.Methods: An English-language literature search was performed with the PubMed database (March 2003–December 2008) using combinations of the search terms sex, gender, and antidepressants. In addition, each antidepressant was identified in the 63rd edition of the Physicians' Desk Reference.Results: The current data suggest that the pharmacokinetics of antidepressants can be substantially different between women and men. Likewise, the response to antidepressants can be quite variable, including sex differences in adverse effects and time to response.Conclusions: Despite the many sex differences reported, there is still little published work systematically evaluating potential sex differences in antidepressant pharmacokinetics and pharmacodynamics. More research is needed to guide the treatment of depression and other mental illnesses.  相似文献   

11.
《Gender Medicine》2012,9(6):457-462
BackgroundAlthough osteoarthritis more commonly affects women than men, women are 3 times less likely to undergo hip or knee replacement surgery compared with men. Disparity in the appropriate utilization of surgery between men and women is a complex subject that must take into account the willingness of a patient to proceed with the operation. Adequately addressing patient concerns before surgery may influence such willingness.ObjectiveWe examined if a gender difference can be identified in the frequency and types of questions submitted by patients scheduled for total hip or total knee arthroplasty.MethodsPatients completed an online interactive preoperative educational program and a database was created containing deidentified information on surgical procedure, sex, year of birth, and any questions that were submitted. Data were also available regarding the total number of patients issued the program, the number of patients who started the program, and the number of patients who completed the program. The results were analyzed by Wilcoxon rank sum test. P values ≤0.05 were considered statistically significant.ResultsAmong the 2770 women and 1708 men included in the study, 935 (34%) and 462 (27%) asked at least 1 question, respectively. Compared with men, women asked a significantly greater number of questions overall (P < 0.001). Women also asked a significantly greater number of questions in the categories Your Condition (P = 0.031), Your Procedure (P < 0.001), and Risks and Benefits (P < 0.001).ConclusionsGender differences in concerns and physicians' ability to adequately address these concerns may contribute to disparity in use of hip and knee replacement surgery between men and women. Effective preoperative counseling for women may require additional resources to address their higher level of questions.  相似文献   

12.
《Gender Medicine》2008,5(4):385-394
Background: A higher incidence of bladder cancer has been reported in men compared with women. Clinical gender differences have been observed but are less well described.Objective: This retrospective analysis further examines clinical differences in the development and manifestation of bladder cancer between men and women.Methods: Consecutive male and female patients with bladder cancer treated between 1969 and 1997 at a single center (University Hospital of Innsbruck, Innsbruck, Austria) were included in the study. Patient characteristics regarding age, tumor classification, localization, and recurrence were compared between male and female patients. Statistical analysis was conducted using the t test, the χ2 test, and the Kaplan-Meier method, with the log-rank test for subgroup analysis.Results: In the 1269 patients (876 men, 393 women) who were examined, 1744 tumors were found. The male-to-female bladder cancer incidence ratio was 2.2:1. Tumors were diagnosed at a significantly younger age in men than in women (mean age: 62 years vs 67 years, respectively; P < 0.001). No difference in the histology of tumors was observed between the sexes. Muscle-invasive tumors more frequently occurred in men than in women (39.8% vs 34.5%; P = NS). In men compared with women, primary tumors were more aggressive (grade 2, 36.6% vs 28.2%; P < 0.001) and tumor recurrences were more invasive (59.0% vs 57.8%; P = NS). Tumors were more often located in the urethra in men than in women (43 [3.4%] vs 9 [1.8%]; P = 0.034), the trigonum (246 [19.8%] vs 75 [14.9%]; P < 0.001), and the bladder dome or vault (128 [10.3%] vs 37 [7.4%]; P = 0.015). Generally, no difference in survival rate was observed between the sexes; only in the subgroup of muscle-invasive tumors (n = 455) did women have a worse overall survival rate than did men (P = 0.022).Conclusions: Clinical gender differences in bladder cancer appear to have a higher incidence in men than in women. In this analysis, women were older at the age of detection, but had less-invasive and less-aggressive tumors than did men. However, women with muscle-invasive disease had a worse overall survival rate than did men in the same subset.  相似文献   

13.
We used a quantitative ethnobotanical approach to analyze factors influencing the use value of plant species among men and women of the Rarámuri people in Cuiteco, Chihuahua, Mexico. We constructed a use value index (UV) combining the use frequency (U) and the quality perception (Q) of useful plant species by local people. We identified all plant species used by the Rarámuri and classified them into 14 general use categories. We interviewed 34 households in the village to compare men and women’s knowledge on the five main general use categories (and on their respective subcategories and specific uses), to document how they practice gathering activities and to calculate scores of plants UV. A total of 226 useful plant species were identified, but only 12% of them had high UV scores for the 42 specific uses defined. When the overall knowledge of plant species was examined, no significant differences were detected between men and women, but significant differences were identified in general use categories such as medicinal plants, plants for construction and domestic goods, but not in plants used as food and firewood. We identified a division of labor in gathering activities associated with gender, with women mainly gathering medicinal and edible plants and being involved in preparing medicines and food, whereas men were primarily gathering and using plants for manufacturing domestic goods, firewood, and building materials. Plant species UV associated to gender were significantly different between men and women at the level of specific uses in the general category of domestic goods and building. Frequency of use is highly associated with plant species quality perception.  相似文献   

14.
Wang P  Chen YM  He LP  Chen CG  Zhang B  Xue WQ  Su YX 《PloS one》2012,7(3):e32736

Background

Many studies showed a moderate cholesterol-lowering effect of plant sterols (PS), but increased circulating PS might be atherogenic. We evaluated the associations between natural dietary intake of PS and carotid intima–media thickness (IMT) and serum lipids.

Methodology/Principal Findings

This community-based cross-sectional study included 1160 men and 2780 women aged 31–75 years. Dietary intakes were assessed using a food-frequency questionnaire. The IMTs at the common, bifurcation and internal carotid artery segments, and fasting serum total (TC), LDL (LDLc) and HDL (HDLc) cholesterol, and triglycerides (TG) were determined. After adjusting for potential covariates, multivariate analysis showed a dose-dependent inverse association of total PS intake with serum TC, LDLc, non-HDLc in women (P<0.001) and in men (P<0.05). As compared to the lowest quartile of PS intake (<206 mg/d), the multivariate-adjusted means of TC, LDLc and non-HDLc in the highest quartile of PS intake (447 mg/d) decreased by 5.0%, 6.2% and 6.5% in women (P<0.005), and by 6.4%, 7.1% and 6.7% (P>0.05) in men. Although the IMTs tended to be lower with greater intake of dietary PS, only small differences in the left internal IMT between the highest and lowest groups were observed among men (−7.6%) and women (−5.1%) (P<0.05). The multivariate analysis showed no significant mean differences among the PS groups in HDLc, TG and IMTs at other studied sites among men and women (all P>0.05).

Conclusions

Greater PS consumption from natural diets is associated with lower serum total, LDL, non-HDL cholesterol and with thinner left internal IMT in women and men.  相似文献   

15.
Two experiments tested whether city commuter and pedestrian groups conformed with ecological predictions of adaptive group size, age, and sex composition. It was predicted that individuals with the greatest reproductive potential would optimize mating contacts and minimize competitive interference by segregating into small, mixed-sex groups, whereas more vulnerable individuals, too young or old for optimum fertility, would tend to aggregate independently of gender in larger groups, which may offer advantages for foraging and predator avoidance. To maximize reproductive potential, mature males should prefer grouping with young women of high fertility, whereas older women should prefer younger men. In Experiment 1, 2,432 persons in three cities were observed on buses, automobiles, and sidewalks, in yoked observations. As predicted, reproductively immature preschool and grade-school children formed larger groups than mature adults (p < 0.0001) and showed no sex differences in grouping. Elderly adults (with decreased reproductive potential) were also found in larger groups than younger adults (p < 0.01) and also showed no sex differences. Sexually mature men and women grouped more with the opposite sex than in all-male or all-female groups (p < 0.00001). Mature adult men were the least aggregative category (p < 0.01): they tended to be alone or in pairs with women, and all-male groups were conspicuously absent (p < 0.005). These findings were consistent across different socioeconomic levels, ethnicities, and subcultures in our samples (p = NS). In Experiment 2, 475 bus passengers in three cities were observed selecting seatmates in a naturalistic choice paradigm. Only sexually mature adults exhibited a significant preference for the sex of their seatmates (p < 0.0005): Young women chose most often to sit with other women, whereas young adult men more frequently chose seatmates of the opposite sex. Young women were chosen more often as seat partners than all age/sex categories combined (p < 0.0005). Young women chose older partners (p < 0.05), while middle-aged women preferred younger women and men (p < 0.0005) as companions. Results are explained in the context of canalized behaviors arising early in human evolution.  相似文献   

16.
《Gender Medicine》2008,5(3):270-278
Background: Although they experience lower mortality rates and lower rates of several chronic diseases than do their male counterparts, aging women are more likely to experience functional impairment in mobility and a general diminished health-related quality of life (HRQoL). The determinants of these gender differences have been the subject of controversy.Objective: This study analyzed gender differences in HRQoL in relation to social and biomedical factors such as age, marital status, educational level, and living arrangements.Methods: Participants were recruited via snowball sampling. All were healthy and lived independently in private homes. Data were obtained from personal interviews, based on a 30-item questionnaire, in the private homes of the participants. Additionally, HRQoL was assessed by means of the abbreviated version of the World Health Organization Quality of Life (WHOQOL-BREF) 26-item questionnaire, which contains 1 general health item, 1 general QoL item, and 24 specific items covering 4 broad domains: physical (DOM I), psychological (DOM II), social (DOM III), and environmental (DOM IV).Results: The participants (98 women, 62 men) enrolled in the study ranged in age from 57 to 95 years (mean [SD] age: 71.8 [8.6] years). The younger age group (aged 57-70 years) comprised 54 women and 25 men, and the older age group (aged >70 years) comprised 44 women and 37 men. Women aged ≤70 years rated their health and QoL significantly higher than did men in the same age group (P = 0.02). These women rated physical capacity (DOM I), social relationships (DOM III), and environment (DOM IV) higher, but not statistically significantly different, than did same-aged men. Women and men exhibited nearly identical psychological health (DOM II) values. Physical capacity (DOM I) differed significantly between women and men aged >70 years (P = 0.03). Women aged >70 years rated their QoL lower than their male counterparts did, although not significantly so. These women depended more on medical treatment, felt significantly less safe in everyday life (P = 0.03), and were less satisfied with themselves.The results of the multiple regression analyses suggest that gender may have a significant impact on general QoL for both age groups (P < 0.01 for the younger age group; P > 0.04 for the older age group). In these analyses, gender also had a significant impact on 2 domains, physical capacity and social relationships (P < 0.02 for both domains), among the participants of the younger age group.Conclusion: Depending on the age group (≤70 vs >70 years) in this small sample of Austrian women and men, gender influenced HRQoL.  相似文献   

17.

Background

Previous reports have shown inconsistent results on clinical outcomes between women and men after stroke, and little is known about gender differences on outcomes in Chinese post-stroke patients. The aim of this study was to explore whether there were gender differences on clinical characteristics and outcomes in Chinese patients after ischemic stroke by using the data from the China National Stroke Registry (CNSR).

Methods and Findings

Out of 12,415 consecutively recruited patients with acute ischemic stroke in the CNSR from 2007 to 2008, 11,560 (93.1%) patients were followed up for 12 months. Their clinical characteristics and outcomes on death, recurrence, and dependency were recorded. The multivariate logistic regression was performed to determine whether there were gender differences in these outcomes. Women were older than men at baseline (67.9 vs. 64.0 years, P<0.001). Women had a higher mortality, recurrence rate, and dependency rate at 3, 6, and 12 months than men, but after adjusting for age, history of diabetes, pre-stroke dependency, stroke severity, in-hospital complications, and other confounders, there were no statistically significant differences in gender on mortality and recurrence rate at 3, 6, and 12 months; and dependency rate at 3, and 6 months. However, the dependency rate at 12 months remained significantly higher in women (odds ratio, 1.24; 95% confidence interval, 1.06 to 1.45).

Conclusions

There are many differences in clinical characteristics between women and men after ischemic stroke in China. Compared with men, women are more dependent at 12 months after stroke. This difference still exists after controlling the potential confounders.  相似文献   

18.
Background: Although biologically based sex differences in the smoking patterns, epidemiology, biomedical markers, and survival rates associated with lung cancer are well documented, examinations of psychosocial gender differences are scarce.Objective: This cross-sectional study examined gender differences in psychosocial factors that are important in the medical management of lung cancer.Methods: A convenience sample of patients who were attending a multidisciplinary lung cancer treatment center (Markey Cancer Center, Lexington, Kentucky) were invited to complete a psychosocial needs assessment. Eligibility criteria included primary diagnosis of lung cancer, age ≥18 years, and being cognitively intact. Measures focused on psychosocial resources, treatment decision-making, social consequences of treatments, and treatment outcomes. Data were collected between the fall of 2005 and the summer of 2006.Results: A total of 47 women and 53 men (mean [SD] age, 62.81 [12.01] years; 95% white) completed the needs assessment. Gender was not found to be associated with demographic characteristics, time until diagnosis, treatment, or survival rate. Smoking histories differed significantly in the proportion of women and men who smoked or were former smokers (P = 0.01) as well as the age when they began to smoke (P = 0.02). There were no significant gender differences in social support networks, general coping, information needs, treatment decision satisfaction, functional health, life satisfaction, financial impact, or service needs. However, significant gender differences did indicate that women favored spiritual practices (P = 0.02) and religious coping (P = 0.04), and were more likely to endorse having a life mission (P = 0.03) and being part of a divine plan (P = 0.01).Conclusions: Previous research has found that religiousness and spirituality improved depressive symptoms and may ease end-of-life despair. In the present study of patients with lung cancer, gender differences in religiousness and spirituality suggest that this may be especially true for women, and that interventions should be directed toward their religious practices and coping.  相似文献   

19.
Erwinia carotovora subsp. betavasculorum Ecb168 produces an antibiotic(s) that suppresses growth of the related bacterium Erwinia carotovora subsp. carotovora in culture and in wounds of potato tubers. Strain Ecb168 also produces and secretes pectolytic enzymes and causes a vascular necrosis and root rot of sugar beet. Genes (out) involved in secretion of pectolytic enzymes by Ecb168 were localized to two HindIII fragments (8.5 and 10.5 kb) of Ecb168 genomic DNA by hybridization to the cloned out region of E. carotovora subsp. carotovora and by complementation of Out- mutants of E. carotovora subsp. carotovora. Out- mutants of Ecb168, which did not secrete pectate lyase into the culture medium, were obtained when deletions internal to either HindIII fragment were introduced into the genome of Ecb168 through marker exchange mutagenesis. Out- mutants of Ecb168 were complemented to the Out+ phenotype by introduction of the corresponding cloned HindIII fragment. Out- mutants of Ecb168 were less virulent than the Out+ parental strain on potato tubers. Strain Ecb168 and Out- derivatives inhibited the growth of E. carotovora subsp. carotovora in culture, indicating that the uncharacterized antibiotic(s) responsible for antagonism was exported through an out-independent mechanism. Strain Ecb168 and Out- derivatives reduced the establishment of large populations of E. carotovora subsp. carotovora in wounds of potato tubers and suppressed tuber soft rot caused by E. carotovora subsp. carotovora.  相似文献   

20.
This study investigated whether there are any gender differences in body-heating strategies during cold stress and whether the immune and neuroendocrine responses to physiological stress differ between men and women. Thirty-two participants (18 men and 14 women) were exposed to acute cold stress by immersion to the manubrium level in 14 °C water. The cold stress continued until rectal temperature (TRE) reached 35.5 °C or for a maximum of 170 min. The responses to cold stress of various indicators of body temperature, insulation, metabolism, shivering, stress, and endocrine and immune function were compared between men and women. During cold stress, TRE and muscle and mean skin temperatures decreased in all subjects (P < 0.001). These variables and the TRE cooling rate did not differ between men and women. The insulative response was greater in women (P < 0.05), whereas metabolic heat production and shivering were greater (P < 0.05) in men. Indicators of cold strain did not differ between men and women, but men exhibited larger changes in the indicators of neuroendocrine (epinephrine level) and in immune (tumor necrosis factor-α level) responses (both P < 0.05). The results of the present study indicated that men exhibited a greater metabolic response and shivering thermogenesis during acute cold stress, whereas women exhibited a greater insulative response. Despite the similar experience of cold strain in men and women, the neuroendocrine and immune responses were larger in men. Contrary to our expectations, the cooling rate was similar in men and women.  相似文献   

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