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1.
Ten independent risk factors were evaluated in an effort to identify predictors of problem diarrhea at weaning and chronic diarrhea in infant and juvenile rhesus monkeys (Macaca mulatta) at the California Primate Research Center. None of the variables proved to be a significant predictor of problem diarrhea at weaning; however, two of the variables were significant predictors for developing chronic diarrhea. Odds ratios, adjusted for other variables in the logistic regression model, showed that compared with females, males were nearly three times more likely to develop chronic diarrhea, and nursery-reared animals were 7.5 times more likely to develop chronic diarrhea than were breast-fed animals. The annual incidence rates for problem diarrhea at weaning for 1978, 1979, and 1980 were 49%, 37%, and 41%, respectively. A weighted average annual incidence rate for problem diarrhea at weaning for the 3-year period was 39%. The incidence rate for chronic diarrhea for the 3-year period was 49%.  相似文献   

2.
Ruderal species, i.e., those that increase their numbers in the presence of disturbance, are not expected to occur in extreme environments. We test whether Echinocereus lindsayi, a cactus from an extreme desert, follows the ruderal trend observed in similar species from mild deserts, or, as theory suggests, it is a non ruderal. Contrary to expectations, its density and fraction of small individuals in the population increased with disturbance. This seemingly results from increased establishment, as it is nursed by rocks exposed by disturbance. A demographic model for two populations, one nearly pristine and another highly disturbed, showed that at the latter site recruitment was more frequent and likely. At the disturbed site the performance of E. lindsayi individuals was usually poor, except on favorable years. Then, competition release caused by disturbance apparently allowed for a better performance compared to the less disturbed site. Despite that this opportunistic behavior would suffice to maintain the population size stable, the large mortality produced by an insect outbreak in two of the four study years caused the population to diminish. In contrast, the population at the less disturbed site was near equilibrium. If the insect outbreak is associated to disturbance, E. lindsayi at the disturbed site would be already experiencing more disturbance than it tolerates. This agrees with the fact that no populations were found at greater disturbance intensities. While, contrary to our hypothesis, E. lindsayi is ruderal, this extreme desert species appears to tolerate far less disturbance than its counterparts from milder areas.  相似文献   

3.
Norethisterone oenanthate (NET-OEN) was given as an injectable contraceptive to 295 healthy women over 1606 woman-months. A modified injection schedule was used. There were no pregnancies, and the 12-month, life-table, use-related discontinuation rate was 39.1/100 users. Menstrual disturbance (10.8/100 women), minor side effects (13.5/100 women), and personal reasons (12.0/100 women) were the main causes of use-related discontinuation. There was no difference in use-related discontinuation rates between women receiving their first injection during a normal menstrual period and those receiving it immediately after a pregnancy. There were no serious side effects. The use of NET-OEN in certain groups of women is recommended, particularly in those in need of highly effective contraception, who cannot or do not wish to take oral contraceptives, who are lactating, or who are awaiting hospital admission for sterilisation.  相似文献   

4.
Concern has arisen in recent years that selection for extreme facial morphology in the domestic dog may be leading to an increased frequency of eye disorders. Corneal ulcers are a common and painful eye problem in domestic dogs that can lead to scarring and/or perforation of the cornea, potentially causing blindness. Exaggerated juvenile-like craniofacial conformations and wide eyes have been suspected as risk factors for corneal ulceration. This study aimed to quantify the relationship between corneal ulceration risk and conformational factors including relative eyelid aperture width, brachycephalic (short-muzzled) skull shape, the presence of a nasal fold (wrinkle), and exposed eye-white. A 14 month cross-sectional study of dogs entering a large UK based small animal referral hospital for both corneal ulcers and unrelated disorders was carried out. Dogs were classed as affected if they were diagnosed with a corneal ulcer using fluorescein dye while at the hospital (whether referred for this disorder or not), or if a previous diagnosis of corneal ulcer(s) was documented in the dogs’ histories. Of 700 dogs recruited, measured and clinically examined, 31 were affected by corneal ulcers. Most cases were male (71%), small breed dogs (mean± SE weight: 11.4±1.1 kg), with the most commonly diagnosed breed being the Pug. Dogs with nasal folds were nearly five times more likely to be affected by corneal ulcers than those without, and brachycephalic dogs (craniofacial ratio <0.5) were twenty times more likely to be affected than non-brachycephalic dogs. A 10% increase in relative eyelid aperture width more than tripled the ulcer risk. Exposed eye-white was associated with a nearly three times increased risk. The results demonstrate that artificially selecting for these facial characteristics greatly heightens the risk of corneal ulcers, and such selection should thus be discouraged to improve canine welfare.  相似文献   

5.
OBJECTIVE--To identify factors influencing decision making by general practitioners in the diagnosis and treatment of lower urinary tract symptoms in women. SETTING--Two suburban London general practices. SUBJECTS--Women presenting to their family doctor with lower urinary tract symptoms. DESIGN--After each consultation the doctor completed a questionnaire on presenting symptoms; clinical examination; investigations undertaken; presence of psychological, social, and menstrual problems; patients'' requests for antibiotics; antibiotic prescribing; knowledge of the patient; attitude towards the consultation; and any other factors assisting in diagnosis and management. Finally, doctors predicted the presence or absence of clinically important bacteriuria. Each woman completed a demographic questionnaire, the 12 item general health questionnaire, and the modified menstrual distress questionnaire, after which each provided a clean catch midstream urine sample. Case notes were examined for information on previous reports of results of urine analysis. RESULTS--When the general practitioners did not know the patients well they were 4.5 times more likely to assume that there was a clinically important infection. When they knew the patient well, they were four times more likely to make a correct prediction of the test result and 12 times less likely to prescribe antibiotics. Doctors were five times more likely to predict the test result correctly in patients from social classes 1 and 2 and were six times more likely to prescribe antibiotics for the older women in the sample. CONCLUSIONS--In women presenting with urinary tract symptoms, these family practitioners seemed to take no particular regard of physical, psychological, or menstrual factors in making their assessments. They were most accurate in their prediction of the result of urine analysis and least likely to prescribe antibiotics when they had a good general knowledge of the patient. Which came first, the diagnosis or prescribing, is difficult to say and probably differed in individual cases. Doctors tended to be more conservative in their management of older women and those whom they knew less well.  相似文献   

6.
In the United Kingdom, Black Grouse Tetrao tetrix have declined in range and abundance during the 20th century. In England at present, birds are largely found only on the margins of managed grouse moors in the north, where more than 80% of birds are confined to the North Pennines Area of Outstanding Natural Beauty. The Black Grouse is one of a group of species potentially at risk from increased human recreational disturbance owing to their threatened status and their use of habitats to which a statutory right of human recreational access has recently been granted. To assess the likely impact of increased disturbance to Black Grouse, 77 were caught and radiotagged between 2002 and 2004, and each was randomly assigned to one of three experimental disturbance categories: no disturbance (low), fortnightly disturbance (moderate) or twice weekly disturbance (high). Birds that were disturbed more regularly flushed at greater distances, especially in spring and winter when birds exposed to high disturbance flushed at 32% greater distances than those in moderate disturbance treatments. There were no differences in fecundity (clutch size, hatching success, breeding success) or survival between disturbance treatments. Winter survival was 78% and summer survival 92%. There was no age-related difference in survival. The disturbance regimes imposed had no discernible impact upon Black Grouse population dynamics. However, in the absence of appropriate data to indicate likely changes in patterns and levels of human recreation resulting from open access, we cannot be sure whether the levels we applied will be representative in the future. Should actual disturbance levels be higher than those we used in this study, we list visitor management options that may help reduce any conflict that arises.  相似文献   

7.
In the United Kingdom, Black Grouse Tetrao tetrix have declined in range and abundance during the 20th century. In England at present, birds are largely found only on the margins of managed grouse moors in the north, where more than 80% of birds are confined to the North Pennines Area of Outstanding Natural Beauty. The Black Grouse is one of a group of species potentially at risk from increased human recreational disturbance owing to their threatened status and their use of habitats to which a statutory right of human recreational access has recently been granted. To assess the likely impact of increased disturbance to Black Grouse, 77 were caught and radiotagged between 2002 and 2004, and each was randomly assigned to one of three experimental disturbance categories: no disturbance (low), fortnightly disturbance (moderate) or twice weekly disturbance (high). Birds that were disturbed more regularly flushed at greater distances, especially in spring and winter when birds exposed to high disturbance flushed at 32% greater distances than those in moderate disturbance treatments. There were no differences in fecundity (clutch size, hatching success, breeding success) or survival between disturbance treatments. Winter survival was 78% and summer survival 92%. There was no age‐related difference in survival. The disturbance regimes imposed had no discernible impact upon Black Grouse population dynamics. However, in the absence of appropriate data to indicate likely changes in patterns and levels of human recreation resulting from open access, we cannot be sure whether the levels we applied will be representative in the future. Should actual disturbance levels be higher than those we used in this study, we list visitor management options that may help reduce any conflict that arises.  相似文献   

8.
Cystic ovarian disease is a major cause of reproductive failure and economic loss for the dairy industry. Many cysts that develop during the early postpartum period regress spontaneously. However, it is difficult to decide at what point it would be more cost effective to treat ovarian cysts than to wait for spontaneous recovery. The objective of this study was to analyze risk factors for the development of the ovarian cystic condition during early and late postpartum, and for its persistence or recovery during the pre-service period in lactating dairy cows. Using multiple logistic regression, we analyzed data derived from 873 lactating dairy cows from a single herd. An ovarian cyst was diagnosed if it was possible to observe a single follicular structure with an antrum diameter > or = 25 mm in the absence of a corpus luteum in three sonograms performed at 7-day intervals. The cystic condition was denoted as early if the cyst was diagnosed 43-49 days postpartum, and late if detected 57-63-day postpartum. Spontaneous cyst regression before 60-day postpartum was regarded as early cystic recovery. For the early cystic group, there were no significant effects of lactation number, body condition score on prepartum Day 60, at parturition or on postpartum Day 30, or of body condition loss from parturition to 30-day postpartum. Cows calving in summer were 2.6 times more likely to develop ovarian cysts than those giving birth in winter. The risk of having a cyst was 1.9 times higher in cows with an abnormal puerperium. A 1-kg increase in milk yield raised the risk of cysts by a factor of 1.05. A 1-unit increase in body condition score (scale from 1 to 5) from prepartum Day 60 to parturition increased the risk of cyst development 8.4 times. Milk production and lactation number were negatively correlated with spontaneous early cyst recovery. A 1-kg decrease in milk production increased the probability of cyst recovery by a factor of 1.06, and a 1-unit drop in lactation number was associated with a 1.4-fold increased probability of cyst recovery. For the late cystic group, there were no significant effects of abnormal puerperium and body score data, except for a prepartum change in body score. Calving season (Odds ratio: 2.3), lactation number (Odds ratio: 1.36), increased milk production (Odds ratio: 1.05) and increased body condition score during the prepartum period (Odds ratio: 4.3) were all related to an increased risk of ovarian cysts. The probability of having a late cyst was 36.6 times greater in cows with early cysts. These findings suggest that it would be profitable to treat multiparous cows having cysts very early in the postpartum period, while treatment of primiparous cows should be delayed, at least until the end of the pre-service period, to provide the opportunity for spontaneous recovery.  相似文献   

9.
为了解大兴安岭森林流域水文过程对森林干扰的响应,利用近配对流域方法,排除了气候变量的时空差异,对比研究了森林干扰后大兴安岭北部典型森林小流域(100 km2)洪峰径流(High flow)和枯水径流(Low flow)径流情势(Flow regimes)的变化趋势。结果表明,森林干扰对枯水径流情势影响显著,与对照流域(小北沟流域)相比,森林干扰(占流域总面积的6.74%)使老沟河流域平均枯水径流流量降低了26.58%,平均枯水径流变异系数值增加了36.77%,并且差异达到极显著水平(P0.01)。另一方面,森林植被的干扰相对增加了森林小流域的洪峰流量、历时和变异性,但与对照流域相比差异均未达到统计显著水平,说明小面积的森林植被干扰未能引起流域洪峰径流情势的显著变化。进一步对配对流域的径流浮动系数(Flashiness Index)的分析发现,森林干扰显著增加了森林小流域的径流浮动性,研究时段内干扰流域的径流浮动系数为0.078,是对照流域(0.057)的1.37倍。大兴安岭北部森林小流域的天然径流情势(Natural flow regimes)对森林干扰比较敏感,在与水文循环联系紧密的区域(例如河岸带),小范围的森林干扰便可以引起径流情势的显著变化,这在未来该地区森林和水资源的管理中需要特别注意。  相似文献   

10.
The aim of the present study was to determine whether certain animal- or management related factors could affect plasma progesterone concentrations on Day 42 of gestation in high producing dairy cows. Factors affecting early fetal loss were also analyzed. The study population was comprised of 199 pregnant cows classified as having high (> or =9 ng/ml) or low (<9 ng/ml) plasma progesterone concentrations. Through logistic regression procedures it was determined that, based on the odds ratio, cows with two or more corpora lutea were three times more likely to have high progesterone concentrations than cows with a single corpus luteum. Low producing cows during the warm season were 2.86 times more likely to have high progesterone concentrations than the remaining cows. Primiparous cows with high concentrations (>4 ng/ml) of pregnancy associated glycoprotein-1 (PAG-1) were 2.73 times more likely to have high progesterone concentrations than the remaining cows. Of the 199 pregnancies, 25 (12.6%) suffered early fetal loss: 22/136 (16.2%) during the warm season and 3/63 (4.8%) during the cool season, all in cows without additional corpora lutea. Based upon the odds ratio, cows without an additional corpus luteum were 3.67 times more likely to suffer fetal loss during the warm season than during the cool season. Our results indicate that milk production, the presence of two or more corpora lutea and plasma PAG-1 concentrations can affect plasma progesterone concentrations at the onset of the fetal period. The presence of an additional corpus luteum strongly diminished the risk of early fetal loss during the warm period.  相似文献   

11.
To investigate whether depression is accompanied by changes in diurnal rhythms of free estradiol and cortisol in different phases of the menstrual cycle, we measured these two hormone levels in saliva samples collected every 2 h for 24 h from 15 healthy normally cycling women and 12 age-matched normally cycling women suffering from major depression taking antidepressants. The assessments were repeated four times over one menstrual cycle: during menstruation and in the late follicular/peri-ovulating, early to mid-luteal and late luteal phases, respectively. Quantification with a nonlinear periodic regression model revealed distinct diurnal rhythms in free estradiol and free cortisol in all subjects. For the diurnal cortisol rhythm, significant differences were found in the peak-width and ultradian amplitude among different menstrual phases, both in controls and depressed patients, while no significant differences were found between the two groups. The diurnal estradiol rhythm, on the other hand, was quite consistent among different menstrual phases within both groups, while the depressed patients had overall larger amplitudes than controls, which is negatively correlated with disease duration. Significant positive correlations between the two hormone rhythms were found for 24-h mean level (mesor), peak, and trough in late luteal phase, and for ultradian harmonics in early to mid-luteal phase in controls, but only for ultradian harmonics in late follicular/peri-ovulating phase and for acrophase in the menstruation phase in depressed patients. A sub-analysis was also performed in patients who received Fluoxetine (n = 7). The findings implicate a close correlation between the hypothalamic-pituitary-adrenal axis and the hypothalamic-pituitary-gonadal axis, both of which may be involved in depression.  相似文献   

12.
目的:探讨子宫动脉栓塞术对于难治性子宫下段瘢痕妊娠的影响。方法:回顾性分析2009年8月至2013年4月经我院收治的85例难治性子宫下段瘢痕妊娠患者,其中41例行子宫动脉栓塞术治疗(观察组),44例行孕囊穿刺术治疗(对照组)。记录两组患者术中出血量、住院时间、转经时间、β-HCG下降至正常时间及激素水平,并比较两种治疗方法的效果。结果:观察组与对照组痊愈率分别为92.68%和90.91%,两组治疗效果比较无显著性差异(P0.05)。与对照组比较,观察组术中出血量显著降低、住院时间及β-HCG下降至正常时间均显著缩短(P0.05);但两组治疗前后激素水平变化比较无显著性差异(P0.05)。术后随访1-3个月,观察组患者转经时间为(32.18±11.46)d,显著低于对照组的(50.03±8.04)d,两组比较差异有统计学意义(P0.05)。结论:子宫动脉栓塞术有效性和安全性更高,与孕囊穿刺术比较能减少术中出血量,缩短住院时间、转经时间及β-HCG下降至正常时间。  相似文献   

13.
The functional capacity of the gonadotrophs was assessed by repeated stimulation with small doses of LH-RH (5 microgram intravenously at 2-hour intervals for 3 injections) in normal women during the early and late follicular phases of the menstrual cycle. The results were compared to those obtained when a single dose (100 microgram) of the neurohormone was administered. During the early follicular phase, the release of LH and FSH remained about equal after the 3 successive injections of the small and after the large dose of LH-RH. During the late follicular phase, the release of LH and fsh increased progressively after the repeated administration of the 5 microgram of the neurohormone while the large dose induced a more pronounced and a more sustained pituitary response. This hypersensitivity of the gonadotrophs is observed when the E2 concentrations are higher than in the early follicular phase of the menstrual cycle.  相似文献   

14.
Reproductive records of 284 female rhesus monkeys housed in six multimale corrals at the California Primate Research Center were examined for the birth seasons 1977–1982 to determine possible associations between the probability of birth or live birth and female age, parity, origin, parturition in the previous season, infant birth date, and infant birth date in previous season. Multiple logistic regression analysis was used to identify and quantitate the effects of factors on the probability of birth or live birth, while controlling for the possibly confounding effects of other factors in the model. Females who had infants early in the previous season were 2.5 times as likely to give birth as those who had infants late in the previous season. Females with two or three previous births were 2.1 times as likely to give birth, and those with four or five previous births were 6.7 times as likely to give birth as were females with no or one previous birth. Controlling for other factors (age, parity, and timing of birth in the previous season), corralborn females were 3.3 times as likely to give birth as either wild-caught or domestic-born monkeys not native to the corrals. Domestic-born females who were not corral natives were 0.3 times as likely to have live births as wild-caught females. Births late in the season were 1.8 times as likely to result in live infants as births early in the season.  相似文献   

15.
W Y Chan  J C Hill 《Prostaglandins》1978,15(2):365-375
We have developed a method which can measure the menstrual prostaglandin (PG) activity in a single tampon specimen by bioassays. This method makes it possible to monitor the menstrual PG activity continuously during menstruation. Using this technique, we determined the menstrual PG patterns of two normal non-dysmenorrheic subjects, one subject on oral contraceptives (OC) and one subject with moderate to severe dysmenorrhea. Two to four cycles were studied per subject. We observed three mentrual patterns among the four subjects studied. Compared to the two normal controls, the subject on OC had a significantly lower menstrual fluid total and menstrual PG activity. The mean values +/- S.E. per menstrual period were 33.4 g +/- 1.5 vs 21.5 g +/- 2.0 and 28.6 microgram (PGF2alpha equivalent) +/- 1.5 vs 11.3 microgram +/- 4.2 respectively (control vs OC). The dysmenorrheic subject had a menstrual fluid total of 37.0 g +/- 1.9 similar to the two normal controls. Her menstrual PG activity (49.8 microgram +/- 7.7), however, was nearly two times higher than the normal controls. In one cycle studied, the dysmenorrheic subject was treated with a PG synthetase inhibitor, ibuprofen (Motrin). Remarkable relief was achieved. The alleviation of symptoms was accompanied by a concomitant marked reduction in the menstrual PG activity.  相似文献   

16.
Serum and urinary levels of unconjugated testosterone, dihydrotestosterone, and oestradiol were measured by specific radioimmunoassays in 10 healthy women in the early follicular phase of their menstrual cycle and in nine healthy women taking oral contraceptives. The contraceptive group had testosterone levels 1-3 times higher and dihydrotestosterone levels two times higher than those in the controls. Serum oestradiol levels in the contraceptive group were much lower than those in the controls and similar to levels in postmenopausal women. The contraceptive group had about twice the urinary excretion of unconjugated (free) testosterone and dihydrotestosterone of the controls, but their excretion of unconjugated oestradiol was 2-7 times lower. The great increase in serum and urinary androgen concentrations, as well as the suppression of oestradiol, may be related to the antiovulatory effect of oral contraceptives.  相似文献   

17.
采用人工模拟降雨试验,研究了踩踏干扰对生物结皮土壤渗透性的影响.结果表明:踩踏干扰显著增加了土壤表面粗糙度,增加幅度与干扰强度有关,50%干扰度下表面粗糙度指数较不干扰增加91%.踩踏干扰延长了坡面产流时间,20%~50%干扰度范围内,随着干扰强度的增加,初始产流时间呈线性增加趋势,50%干扰度的初始产流时间较不干扰增加了169.7%.踩踏干扰增加了土壤渗透性,降低径流系数.50%干扰度的土壤累积入渗量较不干扰增加12.6%;去除生物结皮,土壤渗透性降低,累积入渗量较不干扰降低30.2%.50%以下的干扰度未显著增加土壤侵蚀模数.去除生物结皮,土壤侵蚀模数较不干扰增加10倍.生物结皮破碎度低于50%的干扰在不明显增加土壤流失量的前提下,可增加降水入渗,减小径流风险,改善土壤水分状况.  相似文献   

18.
STUDY OBJECTIVE--To study the association between cognitive impairment and early death in elderly patients living in the community. DESIGN--Case-control study of 410 patients assessed by the mental status questionnaire and followed up after three years. SETTING--A general practice in Inverurie, Aberdeenshire, with 14,000 patients. PATIENTS--205 Patients aged greater than or equal to 65 with cognitive impairment according to the mental status questionnaire (score less than or equal to 8) and 205 patients scoring greater than 8 on the questionnaire matched for age and sex. MAIN OUTCOME MEASURE--Death. RESULTS--The relative risk of death in the cognitively impaired patients overall was 3.5. Those patients who scored less than or equal to 7 on the mental status questionnaire were five times more likely to die than their controls. There was no difference in risk of death between those with severe or moderate cognitive impairment. CONCLUSIONS--Cognitive impairment is associated with early death.  相似文献   

19.
B Holland 《Social biology》1987,34(1-2):78-93
A hazards model was used to estimate the relative risks of infant mortality at various points during the 1st year of life among Malaysian infants who were breastfed for various durations. Data on infant mortality, breastfeeding, and social variables were derived from the retrospective Malaysian Family Life Survey. To provide adequate samples in subperiods of the 1st year of life, analysis intervals were constructed starting at ages 0, 2, 4, and 7 months, and including up to 13 months of exposure. The preferred models for the 1st 3 analysis intervals included breastfeeding as a predictor of infant mortality. It is a particularly significant determinant in the 1st and 3rd intervals. The relative risk of death among those who received food other than human milk was 6.26 compared to those who did not, and the infant who was never breastfed was 12 times more likely to die than the infant who was breastfed at some time. Infants breastfed for intermediate durations had intermediate effects estimates. In each analysis interval, the regression coefficient for unsupplemented breastfeeding was of larger magnitude than that for supplemented breastfeeding. Overall, this study shows that breastfeeding is an important determinant of infant mortality in Malaysia. Studies with larger samples are urged to confirm the preliminary finding of a monotonic relationship between breastfeeding duration and lower infant of mortality risks. However, this analysis demonstrates the utility of hazard model methodology as a powerful tool for calculating relative risk estimates when the sample size is relatively small and there are numerous covariates.  相似文献   

20.
This 1981 study is the 1st of its kind in Nepal. Analysis using a logit-linear model showed that contraceptive use in Nepal depends on many factors. Women aged 35-49 are 3 times more likely than women aged 15-24 to use contraceptives. Women with 4 or more children are 8 times more likely to use contraceptives than women with 1 or no children, and 2.5 times more likely than women with 2 or 3 children. The use of contraceptives is greatest among women whose offspring includes more sons than daughters, and least among women whose offspring are all daughters. Women who desire no more children are 5 to 6 times more likely to use contraceptives than women who desire more children. Women who have discussed desired family size with their husbands are more than 4 times more likely to use contraceptives than women lacking this type of communication. Women with some schooling are twice as likely to use contraceptives as women with no schooling. Contraceptive use is higher among women who do nonfarm work than farm work, and higher still among women who do not work. Urban women were almost twice as likely to use contraceptives as rural women. Women with less than 1 hour access to a family planning service outlet were 2 to 3 times more likely to use contraceptives than women whose access to these facilities was greater than 1 hour. The number of previous child losses per woman had no significant effect in contraceptive use. Conclusions are based on analysis of data from the Nepal Contraceptive Prevalence Survey, 1981.  相似文献   

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