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1.
Surgical exploration for suspected appendicitis is the most common acute abdominal operation in children and young adults. However, in 20-30% of such explorations, the appendix is not inflamed. It is commonly thought that a perforated appendix may result in tubal dysfunction because of peritoneal adhesions after inflammation and a subsequent increased risk for extrauterine pregnancy and female infertility. Findings are reported from an examination of fertility patterns in women who had their appendix removed in childhood. 9840 women under age 15 years when they underwent appendicectomy between 1964 and 1983 were age-matched with 47,590 control women from the Swedish general population and followed until 1994. Women with a history of perforated appendix had a similar rate of first birth as the control women, as well as a similar distribution of parity at the end of follow-up. Women who had had a normal appendix removed had an increased rate of first births, and on average had their first child at an earlier age and reached a higher parity than control women. These findings therefore suggest that a history of perforated appendix in childhood does not seem to have long-term negative consequences upon female fertility. 相似文献
2.
Competing demands for water have resulted in many wetlands becoming either more permanently flooded or more permanently dry. It has been stated that such changes may lead to a loss of diversity in wetland communities; yet to date, this has not been tested experimentally. In this study, we experimentally test the hypothesis that increasing the hydrologic stability of wetlands results in reduced abundance, richness and diversity of aquatic biota emerging from wetland sediments. Sediment was collected from 19 wetlands that were divided into five groups (permanently flooded and wetlands that had been dry for 2, 7, 11 and 30 years). Aquatic plant communities germinating from the sediment of wetlands that had been permanently inundated and those that had been dry for 30 years had lower species richness and number of individuals than wetlands with intermediate flooding histories. For microfaunal communities, significantly less individuals but more taxa hatched from wetlands that had been permanently flooded or dry for 2 years than the other wetland groups. These results provide evidence of reduced biotic diversity as hydrological stability is increased under the common management scenarios of making wetlands more permanently wet or dry. 相似文献
3.
E. DANCHIN 《Ibis》1992,134(2):134-141
Kittiwakes Rissa tridactyla (683 chicks and 64 adults) were examined for ectoparasites in three breeding areas: Isle of May (Firth of Forth, Scotland; eight colonies of approximately known age of occupation on natural sites), North Shields and Gateshead (Tyne and Wear, England; well established colonies of known age on buildings). All the 208 ticks collected were Ixodes uriae. On the Isle of May, a colony which had only been established for 7 years was already infested by ticks. Tick incidence increased significantly with the length of colonization of the area during the first 30 years. Age of colonization did not have an effect after 30 years. In Gateshead only a single adult among the 127 birds examined had a tick. No ticks were found on the 106 chicks born at North Shields checked in 1987 or in 1988. However, among nine visiting newly-fledged chicks from neighbouring colonies caught at the North Shields colony, six had either ticks or scars of previous infestation. Some visiting chicks remained for several days in the host colony and were even fed by the owners of visited nests. Ixodes uriae may thus spread from one colony to another during visits of newly-fledged infested chicks to neighbouring colonies. The absence of any infestation in old colonies (38 years in North Shields and 17 years in Gateshead) on buildings that are regularly visited by newly fledged infested chicks, suggests that buildings may lack the rock refuges necessary for tick survival from one year to the next. In this respect Kittiwake colonies on buildings are rather atypical. 相似文献
4.
The NBT reduction spontaneous and stimulated test was carried out on 90 men; 30 of which had never smoked cigarettes, 28 subjects have smoked for up to 10 years and 32 subjects--since over 10 years. The investigations demonstrated show that in subjects smoking cigarettes for up to 10 years the spontaneous and stimulated ability of the neutrophils to reduce NBT was increased whereas in the subjects smoking cigarettes since over 10 years impairment of the stimulated NBT reduction was demonstrated. We've come to a conclusion that an exposure to tobacco smoke may activate oxidation-reduction processes of the neutrophils in the initial stage and impair them in longer stage of smoking. 相似文献
5.
P M Lago W A Escobar P R Hernández M J Elías R P Puente 《Journal of hygiene, epidemiology, microbiology, and immunology》1988,32(3):315-319
Neutralizing antibodies to polioviruses in cord blood of neonates born from 64 mothers under age 20 and in 53 mothers aged 30 years and over were investigated in order to know and compare the transfer to newborns of antibodies to polioviruses produced by live oral vaccine mainly and those antibodies induced by natural contact with wild poliovirus strains. Total immunity for the two groups was higher than 80% for the three types of polioviruses, with only virus 3 showing an immunity below 80% (77.4%) in mothers aged 30 years and over. Average geometric titers though relatively low may be considered satisfactory. However, there is a statistically significant difference in titers to poliovirus type 2 (24.9) in mothers over age 30 years as compared to those found in mothers below age 20 years (10.8), for which we have found no explanation. It is not deemed necessary for the time being to take special prophylactic measures with these children given the occurrent epidemiologic status quo. 相似文献
6.
Granulosa cell tumours of the ovary are rare, comprising around 3% of ovarian tumours. These tumours have preponderance for local spread and extremely late recurrence. Although previous cases of recurrence have been described, it is extremely unusual for these tumours to recur after thirty years. We describe a case of recurrence of granulosa cell tumour after 30 years, presenting as small bowel obstruction. The patient had not been followed up after the original surgery, and on histological analysis, recurrence of the original tumour was confirmed. This case report emphasises the necessity for lifelong follow-up of patients who have had these tumours excised, and also the unusual way in which these tumours can recur. 相似文献
7.
Seal KH Ochoa KC Hahn JA Tulsky JP Edlin BR Moss AR 《The Western journal of medicine》2000,172(1):16-20
Objective To compare the demographic characteristics and risk behaviors for hepatitis B infection among injection drug users younger than 30 years with those aged 30 or older and to evaluate participants'' knowledge, attitudes, and experiences of infection, screening, and vaccination against hepatitis B virus. Design A systematic sample of injection drug users not currently in a treatment program were recruited and interviewed at needle exchange programs and community sites. Participants 135 injection drug users younger than 30 years and 96 injection drug users aged 30 or older. Results Injection drug users younger than 30 were twice as likely as drug users aged 30 or older to report having shared needles in the past 30 days (36/135 [27%] vs 12/96 [13%]). Injection drug users younger than 30 were also twice as likely to report having had more than two sexual partners in the past 6 months (80/135 [59%] vs 29/96 [30%]). Although 88 of 135 (68%) young injection drug users reported having had contact with medical providers within the past 6 months only 13 of 135 (10%) had completed the hepatitis B vaccine series and only 16 of (13%) perceived themselves as being at high risk of becoming infected with the virus. Conclusion Few young injection drug users have been immunized even though they have more frequent contact with medical providers and are at a higher risk for new hepatitis B infection than older drug users. Clinicians caring for young injection drug users and others at high risk of infection should provide education, screening, and vaccination to reduce an important source of hepatitis B infection. 相似文献
8.
Serum and lymphocyte levels of heat shock protein 70 in aging: a study in the normal Chinese population 总被引:2,自引:0,他引:2
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Jin X Wang R Xiao C Cheng L Wang F Yang L Feng T Chen M Chen S Fu X Deng J Wang R Tang F Wei Q Tanguay RM Wu T 《Cell stress & chaperones》2004,9(1):69-75
Heat shock proteins (Hsps) have been reported to play an important role in both physiological and pathological processes. Hsps also may serve as biomarkers for evaluating disease states and exposure to environmental stresses. Whether Hsp levels in serum and lymphocytes are correlated with age and sex is largely unknown. In this study, we analyzed serum Hsp70 (the most abundant mammalian Hsp) levels by using Western dot blot in 327 healthy male donors aged between 15 and 50 years. We also investigated the association between Hsp70 levels and age in lymphocytes of 80 normal individuals aged between 40 and 77 years because various chronic diseases increase after the age of 40 years. Our data showed that serum Hsp70 levels were positively correlated with age in subjects aged between 15 and 30 years (P < 0.05) but negatively correlated with age in subjects aged between 30 and 50 years (P < 0.05). Serum Hsp70 levels were the highest in individuals aged between 25 and 30 years among all age groups. In the lymphocyte study there also was a significant age-related decrease in Hsp70 levels in lymphocytes of individuals older than 40 years. The Hsp70 levels were negatively correlated with age (r = -3.708, P < 0.0001) but not with sex (r = -10.536, P = 0.452). This suggests that both serum and lymphocyte Hsp70 levels are age-related and that these may be linked to age-related stress. Thus, age is an important factor in using serum and lymphocyte Hsp70 as biomarkers to evaluate the disease states or exposure to environmental stresses (or both). 相似文献
9.
Novel components of human mitotic chromosomes identified by proteomic analysis of the chromosome scaffold fraction 总被引:2,自引:2,他引:0
Chromosomal nonhistone proteins have important roles in mitotic chromosome formation and dynamics. In order to identify novel abundant proteins with a potential involvement in these processes, we initiated a proteomic screen of the chromosome scaffold fraction. This screen identified 79 proteins, 30 of which had not previously been described as components of mitotic chromosomes. Furthermore, half of these proteins had no documented function. We analyzed the cell-cycle dependent distribution of three uncharacterized proteins by expressing them as green fluorescent protein (GFP) fusions and showed that they associate with mitotic chromosomes in vivo. One of the proteins, nuclear protein p30, is a novel component of the inner centromere. Over-expression experiments indicated that p30 may have an active role in the formation of centromeric heterochromatin. 相似文献
10.
Vern L. Katz 《Human nature (Hawthorne, N.Y.)》1993,4(4):367-382
This discussion focuses on two important trends in American childbirth that have emerged in the past 30 years, the demand for a perfect baby and the desire for a perfect birth. These two trends are particularly important in the subgroup of middle-class women who have decided on delayed childbearing. Tremendous technological innovations, such as ultra-sound, prenatal genetic analysis, and fetal monitoring, have promoted the perception that physicians can control the prenatal environment and predict the pregnancy outcome. This expectation may lead to bitterness and anger in the event of an adverse pregnancy outcome. In contrast, women and their families have also come to desire more control over the birth experience. If the parents’ birth plan is not achieved and their expectations not fulfilled, many parents feel they have not performed well. When the physician acts as a guide in the birth process, parents and physicians together may transcend the conflict to achieve a more satisfactory birth experience. 相似文献
11.
Aneuploid spermatozoa in infertile men: teratozoospermia. 总被引:7,自引:0,他引:7
Cristina Templado Tina Hoang Calvin Greene Alfred Rademaker Judy Chernos Renée Martin 《Molecular reproduction and development》2002,61(2):200-204
We and others have demonstrated that infertile men who are candidates for intracytoplasmic sperm injection (ICSI) have an increased frequency of chromosomal abnormalities in their sperm. Reports based on prenatal diagnosis of ICSI pregnancies have confirmed the increased frequency of chromosomal abnormalities in offspring. Most studies to date have lumped various types of infertility together. However, it is quite likely that some subsets of infertility have an increased risk of sperm chromosomal abnormalities whereas others do not. We have studied nine men with severe teratozoospermia (WHO, 1992 criteria, 0-13% morphologically normal forms) by multicolour fluorescence in situ hybridisation (FISH) analysis to determine if they have an increased frequency of disomy for chromosomes 13, 21, XX, YY, and XY, as well as diploidy. All of the men also had aesthenozoospermia (< 50% forward progression) but none of the men had oligozoospermia (<20 x 10(6) sperm/ml). The patients ranged in age from 20 to 49 years (mean 33.2 years) in comparison to 18 normal control donors who were 23 to 58 years (mean 35.6 years). The control donors had normal semen parameters and no history of infertility. A total of 180,566 sperm were scored in the teratozoospermic men with a minimum of 10,000 sperm analyzed/donor/chromosome probe. There was a significant increase in the frequency of disomy in teratozoospermic men compared to controls for chromosomes 13 (.23 vs.13%), XX (.13 vs.05%), and XY (.50 vs.30%) (P <.0001, 2-tailed Z statistic). This study indicates that men with teratozoospermia and aesthenozoospermia but with normal concentrations of sperm have a significantly increased frequency of sperm chromosomal abnormalities. 相似文献
12.
JOHN H. CROTHERS 《Biological journal of the Linnean Society. Linnean Society of London》1987,32(1):49-57
Two hundred and fifty-eight thousand A-level students have attended one-week field courses at Field Studies Council Residential Centres during the past 30 years. Biology courses have had a strongly ecological basis throughout, with an emphasis on the study of the whole environment. Only in recent years have financial constraints forced the organization to restructure academically-desirable programmes in favour of overtly syllabus-orientated curricula. There have, however, been but trivial changes in the pattern of work. The emphasis of the field course is based firmly on the students' own field and laboratory observations. Staff are facilitators not dictators. 相似文献
13.
Uterine leiomyomata are common, affecting 70-80% of women between 30 and 50 years of age. Leiomyomata have been reported for a variety of primate species, although prevalence rates and treatments have not been widely reported. The prevalence, diagnosis, and treatment of uterine leiomyomata in the Alamogordo Primate Facility and the Keeling Center for Comparative Medicine and Research were examined. Uterine leiomyomata were diagnosed in 28.4% of chimpanzees with an average age at diagnosis of 30.4 ± 8.0 years. Advanced age (>30 years) was related to an increase in leiomyomata and use of hormonal contraception was related to a decrease in leiomyomata. As the captive chimpanzee population ages, the incidence of leiomyomata among female chimpanzees will likely increase. The introduction of progesterone-based contraception for nonbreeding research and zoological chimpanzees may reduce the development of leiomyomata. Finally, all chimpanzee facilities should institute aggressive screening programs and carefully consider treatment plans. 相似文献
14.
Out of 602 consecutive people who had been prisoners of war in the Far East and were screened for tropical diseases, 88 (15%) were found to have Strongyloides stercoralis infection a mean period of 30 years after their return from the tropics. The classical strongyloid creeping eruption was the most common symptom (84%), while gastrointestinal disturbances were rare (5%). Thiabendazole was highly effective in eradicating the infection. Strongyloidiasis is an important condition, as when the host is immunosuppressed fatal hyperinfection may occur. Many undiagnosed cases of strongyloidiasis must exist among former prisoners of war, and it is thus important to identify and treat these patients. 相似文献
15.
Age changes in fields 39 and 40 (after Broadman) have been studied in a 100 years and 6 months old man died from peritonitis resulted from the surgical intervention, performed in connection with strangulation of the hernia. In the medical history there were no ++neuro-physical signs. The material was taken in 1 h 15 min after clinical death had been stated. The results obtained have been compared with those studied in the brain of persons, who had not yet reached the age of 100 years and had not any signs of ++neuro-physical disturbances and died after urgent surgical interventions in the abdominal cavity. In this group of persons the material for investigation was taken in 15-30 min after clinical death had been stated. The technique for treatment the material, its preparation for electron-microscopical examination is identical. Immersion fixation has been applied. The material obtained from an old animal fixed by means of vital perfusion of 2.5% glutaraldehyde solution is also used. In the person of 100 years and 6 months old the changes do not practically differ from those obtained from persons of younger age, however, the time from the statement of clinical death up to obtaining the material essentially influences preservation of the synaptic apparatus components. 相似文献
16.
By the end of 2004, more than 20 HIV-1 vaccine candidates will have entered clinical testing in at least 30 trials worldwide. Almost half of these vaccines include nonstructural HIV-1 gene products. This represents an important innovation in the HIV vaccine field, because until 9 years ago not even preclinical testing in small animal models had been carried out with such immunogens. This review briefly discusses the experimental evidence that provides the rationale for the use of nonstructural HIV-1 gene products as vaccine antigens, and summarizes the current status and the future development of these novel vaccines. 相似文献
17.
Climate change is likely to have severe effects on water availability in Ethiopia. The aim of the present study was to assess the impact of climate change on the Gilgel Abay River, Upper Blue Nile Basin. The Statistical Downscaling Tool (SDSM) was used to downscale the HadCM3 (Hadley centre Climate Model 3) Global Circulation Model (GCM) scenario data into finer scale resolution. The Soil and Water Assessment Tool (SWAT) was set up, calibrated, and validated. SDSM downscaled climate outputs were used as an input to the SWAT model. The climate projection analysis was done by dividing the period 2010-2100 into three time windows with each 30 years of data. The period 1990-2001 was taken as the baseline period against which comparison was made. Results showed that annual mean precipitation may decrease in the first 30-year period but increase in the following two 30-year periods. The decrease in mean monthly precipitation may be as much as about -30% during 2010-2040 but the increase may be more than +30% in 2070-2100. The impact of climate change may cause a decrease in mean monthly flow volume between -40% to -50% during 2010-2040 but may increase by more than the double during 2070-2100. Climate change appears to have negligible effect on low flow conditions of the river. Seasonal mean flow volume, however, may increase by more than the double and +30% to +40% for the Belg (small rainy season) and Kiremit (main rainy season) periods, respectively. Overall, it appears that climate change will result in an annual increase in flow volume for the Gilgel Abay River. The increase in flow is likely to have considerable importance for local small scale irrigation activities. Moreover, it will help harnessing a significant amount of water for ongoing dam projects in the Gilgel Abay River Basin. 相似文献
18.
Incidence of hysterectomy and tubal ligation in public hospitals in south Australia, 1980-82 总被引:1,自引:0,他引:1
Physicians performed 3866 hysterectomies and 5622 tubal ligations in South Australian public hospitals between 1980 and 1982. Data did not indicate if the hysterectomies occurred for medical reasons or for sterilization, though, but for women less than 40 years of age the procedure could have been used to prevent childbearing. 83% of the women in the study were currently married. Average annual incidence rates for women aged 15 and older were 773 hysterectomies and 1125 tubal ligations per 100,000 women. 54% of the women who had a hysterectomy were less than 45 years old. Median age for women who experienced a hysterectomy was 44, as for those who had a tubal ligation the median age was 32. Most women (60%) who underwent a tubal ligation were between 25-34 years old, and 8% were younger than 25 years old. Women born overseas comprised 37% of women who had a hysterectomy and 31% of those who had a tubal ligation. The highest age-specific hysterectomy rate occurred in the 45 to 49 age group whereas the sterilization rate peaked at the 30 to 34 range. Based on only the public hospital data, researchers estimated that women in South Australia had a 1 in 6 chance of having a hysterectomy and a 1 in 5 chance of undergoing a tubal ligation. Further research is needed to learn why women choose to have elective surgery when it is not medically necessary. The possibility exists that they choose it over oral contraceptives because of the adverse publicity they have received. 相似文献
19.
Zhijun Wang Chen Xie Ying Huang Christopher Wai Kei Lam Moses S. S. Chow 《Phytochemistry Reviews》2014,13(1):323-337
Drug resistance is a major problem in cancer chemotherapy and such resistance may be responsible for treatment failure in 90 % of patients with metastatic cancer. From the research work in the past 30 years, multi-mechanisms responsible for the development of drug resistance have been identified. However, to date single agents that target specific single mechanisms of resistance have not been proven effective. Theoretically, herbs have the potential to target multi-mechanisms of resistance since they contain multiple components and may provide an exciting potential in overcoming drug resistance. The present paper provides an overview of the known mechanisms of resistance and reviews the existing data on herbal medicines (Chinese medicines) as chemosensitizing agents from both the English and Chinese literature. Our review found that certain herbs are capable of inducing strong chemosensitizing effect with various mechanisms, but relevant information useful for development of herbs as viable products for therapeutic use is generally inadequate. Ideas for improving in vitro screening and animal/clinical studies that could enhance future development of herbal product as chemosensitizing agent for the treatment of resistant cancer are also discussed. 相似文献
20.
Preeclampsia is a major cause of perinatal mortality and disease affecting 5–10% of all pregnancies worldwide, but its etiology remains poorly understood despite considerable research effort. Parent-offspring conflict theory suggests that such hypertensive disorders of pregnancy may have evolved through the ability of fetal genes to increase maternal blood pressure as this enhances general nutrient supply. However, such mechanisms for inducing hypertension in pregnancy would need to incur sufficient offspring health benefits to compensate for the obvious risks for maternal and fetal health towards the end of pregnancy in order to explain why these disorders have not been removed by natural selection in our hunter-gatherer ancestors. We analyzed >750,000 live births in the Danish National Patient Registry and all registered medical diagnoses for up to 30 years after birth. We show that offspring exposed to pregnancy-induced hypertension (PIH) in trimester 1 had significantly reduced overall later-life disease risks, but increased risks when PIH exposure started or developed as preeclampsia in later trimesters. Similar patterns were found for first-year mortality. These results suggest that early PIH leading to improved postpartum survival and health represents a balanced compromise between the reproductive interests of parents and offspring, whereas later onset of PIH may reflect an unbalanced parent-offspring conflict at the detriment of maternal and offspring health. 相似文献