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41.
In comparison to estradiol-17beta, the naturally synthesized estradiol-17beta-17-fatty acid esters are potent estrogens when administered subcutaneously. A lipophilic character of estradiol-17-esters could partially protect them from metabolic inactivation. In order to compare their relative estrogenic potency when administered orally, the uterotrophic response to different dosages (0, 2.5, 25, 250 and 2500 nmol/kg BW/day) of estradiol-17beta and estradiol-17beta-17-stearate was assessed in juvenile Sprague-Dawley female rats. Estrogens were administered by oral gavage once a day for 6 days. On the 7th day uterus and vagina were dissected, weighed, and examined microscopically. At 2.5 and 25 nmol/kg BW/day, no difference was detected in the uterus weight compared to control animals which received the vehicle alone (corn oil). At 250 nmol/kg BW/day, the uterotrophic response was maximal in estradiol-17beta-17-stearate-treated animals (x2.40-2.70), whereas it was moderate in estradiol-17beta-treated rats (x1.86) at the same dosage. This differential weight gain effect of estradiol-17beta-17-stearate was correlated with typical microscopic changes in uterus and vagina. The results are in favour of a stronger estrogenic effect of orally given lipoidal estrogens compared to estradiol-17beta. This could be explained by a slower but sustained absorption of estradiol-17beta released from estradiol-17beta-17-stearate by esterases and/or by a facilitated transfer of esters in the lymphatic circulation.  相似文献   
42.
X4 and R5 HIV strains are present in the semen of men infected with HIV but R5 isolates are transmitted preferentially. The role of human epithelial cells in this selection is addressed. Three human cervical cell lines-CaSki, SiHa, and HEC1A-and normal human vaginal cells from HIV-negative donors were characterized for HIV receptor expression and incubated with X4 and R5 laboratory-adapted strains or primary isolates. The infection was assessed by detection of intracellular HIV DNA. The three cell lines were shown to express on their surface the CXCR4 and GalCer molecules, but not the CD4 and CCR5 ones. The three cell lines and normal human vaginal cells were found to be selectively permissive to X4 HIV entry; the preincubation of the cell lines with rhSDF-1 inhibited this infection. The detection of the intracellular proviral DNA in the cell lines and in normal human vaginal cells demonstrated a selective integration of X4 strains. Additional experiments showed that no extracellular RNA was detected in the supernatants of HEC1A cells infected by X4 isolates either after 18 days of culture or after incubation with PHA-stimulated PBMCs and that no transmission occurred after co-culture between infected HEC1A cells and PHA-stimulated PBMCs. These results suggest specific sequestration of X4 strains by genital epithelial cells, which could explain, at least in part, the HIV tropism selection process during sexual intercourse.  相似文献   
43.
新兵训练后功能性闭经女兵的心身症状与激素水平   总被引:1,自引:0,他引:1  
目的:探讨新人伍女兵功能性下丘脑性闭经(FHA)者与月经正常者激素水平及心理健康状况的差异。方法:在某部队新人伍女兵98人接受了为期近4个月的体能训练之后,有54人出现闭经.其中闭经3个月以上者有35人(研究组)。训练后月经正常、在采血时月经周期处于第5~11天者有26人(对照组)。分别测定她们血清中的促卵泡生成素(FSH)、黄体生成素(LH)、雌二醇(E_2)、孕酮(P)、泌乳素(PRL)、睾酮(T)、ACTH、T_3、T_4的水平,并用SCL-90分别评定她们的心理健康状况。结果:FHA 者血清FSH 值为4.96±1.73 mIU/ml,LH 值为2.63±1.78 mIU/ml,E_2的值为7.23±5.37 pg/ml,对照组血清相应值为10.73±2.30mIU/ml、12.31±2.15mIU/ml、41.67±6.13pg/ml,差异有统计学意义(P<0.01),闭经组低于对照组。FHA 组SCL-90的躯体化、人际敏感、抑郁、焦虑及其他因子分大于2的比率分别为:51.4%、42.9%、48.6%、51.4%及37.1%;而对照组这5项分值大于2的比率分别为15.4%、15.4%、19.2%、21.3%及11.5%,两组间这5个因子大于2的人数差异有统计学显著意义(P<0.05),闭经组高于对照组。结论:诊断为FHA 的女兵与月经正常女兵的激素水平有差异,闭经组心身症状的发生率也高于对照组。  相似文献   
44.
Alleles at the brown locus ofDrosophila melanogaster combined with homozygous scarlet provide a useful model to demonstrate minority advantage of males in mating. Heterozygotes with orange (O) eyes equal in numbers to homozygotes with red (R) eyes (1010 in both sexes) displayed no bias favoring either eye color, but each eye color was favored when males occurred in a minority ratio (218). In direct observation of single females with equal numbers of males (33) as controls,O males courted less and more slowly thanR males, but females mated with either type without bias. When unequal (41), the minority males were successful at more than twice the frequency expected. Whether successful or not, the minority males did not change their level of courtship, and thus cannot be said to compensate for their frequency in any way. The time between first courtship and mating was less for the minority males than for the majority males. We discard the hypothesis that the minority male will be accepted immediately or ahead of a majority male, because the opposite tended to occur: that if a minority male courted first he was less likely to be successful than if he waited until the majority courted. Our results then are in conformity with the hypothesis that a female samples males and their courtship cues, thus becoming habituated to the majority of the first courting male, but she accepts a male with a cue different from that which she originally detected but avoided. That male is most often the minority.This research was supported in part by National Science Foundation Grants GB-34206 to August 31, 1974, and BMS 72-02110 after that date.  相似文献   
45.
BACKGROUND: This study in humans was undertaken to evaluate earlier results from animal research showing a retrograde migration of glove powder from the vagina into the intra-abdominal cavity. METHODS: One study group was gynaecologically examined with powdered gloves the day before an abdominal hysterectomy and another group 4 days pre-operatively. There were two control groups similarly examined with powder-free gloves. Cell smears were taken from the peritoneal fluid and during the operation further smears were taken from the Fallopian tubes, uterine cavity and cervical canal. RESULTS: Statistically significant differences were found for large starch particles at all locations between the study and control groups examined 1 day pre-operatively. Considering small starch particles, there were significant differences in cervix (P < 0.001), uterus (P < 0.01) and the Fallopian tubes (P < 0.01). The combined results also show significant differences between both large and small starch particles in cervix, uterus and the Fallopian tubes. There were also differences between the study and control groups examined 4 days pre-operatively, but these were not statistically significant except for small and large starch particles in uterus (P < 0.01, P < 0.05) and cervix (P < 0.05, P < 0.05). CONCLUSIONS: This study has pointed out a retrograde migration of starch also in humans after a gynaecological examination with powdered gloves. Consequently, powder or any other potentially harmful substance that can migrate from the vagina should be avoided.  相似文献   
46.
To assess the frequency of chromosomal aberrations in French candidates for intracytoplasmic sperm injection (ICSI), and to explore the existence of a female chromosomal factor in some cases of couple infertility, a collaborative retrospective clinical and cytogenetic study was performed, launched by the Association des Cytogénéticiens de Langue Franciaise (ACLF). The karyotypes of 3208 patients [2196 men (68.4%), 1012 (31.6%) women] included in ICSI programmes over a 3-year period in France were collected. A total of 183 aberrant karyotypes was diagnosed, corresponding to an abnormality frequency of 6.1% (134/2196) for men and 4.84% (49/1012) for women. The following frequencies of abnormalities were observed respectively for men and women: 1.23% (n = 27) and 0.69% (n = 7) for reciprocal translocations, 0.82% (n = 18) and 0.69% (n = 7) for Robertsonian translocations, 0.13% (n = 3) and 0.69% (n = 7) for inversions, 3.32% (n = 73) and 2.77% (n = 28) for numerical sex chromosome aberrations, and 0.59% (n = 13) and 0% for other structural aberrations. Among the male patients of this latter group, 0.40% (n = 9) had a Y chromosome abnormality. Among the male patients with numerical sex chromosome abnormalities, 2.23% (n = 49) were 47,XXY, 0.32% (n = 7) were 47,XYY, and 0.77% (n = 17) had a mosaicism for numerical sex chromosome anomalies. All the female patients with sex chromosome abnormalities (2.77%, n = 28) had mosaicism for numerical sex chromosome anomalies. Even if these cases-the significance of which was sometimes questioned-were disregarded in the analysis, 2.08% (21/1012) of abnormal karyotypes remained in women. An overall increased frequency of chromosomal aberrations was found, and this confirmed that in some cases of poor reproductive outcome there may be a contribution of maternal chromosome aberrations. Indeed, the existence of a chromosome abnormality in the female partner was associated with the group of infertile men in which there was no apparent cause of infertility.  相似文献   
47.
OBJECTIVE: To examine college athletic trainers' confidence in helping female athletes who have eating disorders. DESIGN AND SETTING: We mailed a 4-page, 53-item survey to head certified athletic trainers at all National Collegiate Athletic Association Division IA and IAA institutions (N = 236). A 2- wave mailing design was used to increase response rate. SUBJECTS: A total of 171 athletic trainers returned completed surveys for a response rate of 77%. Eleven institutions either did not identify their head athletic trainer or did not have an identifiable mailing address. Two surveys were undeliverable because of incorrect mailing addresses. MEASUREMENTS: The survey consisted of 4 subscales: (1) efficacy expectation, (2) outcome expectation, (3) outcome value, and (4) experience in dealing with eating disorders. Content validity was established by review from a national panel of experts. Reliability ranged from.66 to.73 for the subscales. RESULTS: Although virtually all athletic trainers (91%) had dealt with a female athlete with an eating disorder, only 1 in 4 (27%) felt confident identifying a female athlete with an eating disorder, and only 1 in 3 (38%) felt confident asking an athlete if she had an eating disorder. One in 4 athletic trainers (25%) worked at an institution that did not have a policy on handling eating disorders. Almost all athletic trainers (93%) felt that increased attention needs to be paid to preventing eating disorders among collegiate female athletes. CONCLUSIONS: Collegiate athletic programs are encouraged to develop and implement eating-disorder policies. Continuing education on the prevention of eating disorders among athletes is also strongly recommended.  相似文献   
48.
北京女校大学生进食障碍与心境的问卷调查   总被引:9,自引:2,他引:9  
目的:探讨北京女校大学生的进食障碍状况及其相关心境。方法:通过班级集体施测的方法,采用进食障碍问卷(EDI)和简式简明心境问卷(POMS-SF)对北京市女子大学352名年龄为17-25岁的大学生进行调查,同时搜集被试的体重、身高等人口学资料(身高=161±5厘米,体重=52.3±5.61千克)。结果:当前北京女校大学生进食障碍的相关行为普遍存在;与体形偏瘦和过瘦的学生相比,体形正常的大学生进食障碍相关的不良态度和行为表现较为严重;进食障碍相关的不良态度和行为存在年级差异(X~2=17.94,P<0.01),大一、大四较为严重;进食障碍症状与不良心境相关(r=0.42,P<0.01)。结论:北京女校大学生进食障碍相关态度和行为较严重,并与其心境和其它因素有一定关系。  相似文献   
49.
BACKGROUND: Since the introduction of ICSI in 1991, medical outcome studies on ICSI children have been performed, but few have addressed developmental outcome. Hence, this outcome was assessed by performing a standard developmental test on children born after ICSI as compared with children born after IVF, at the age of 2 years. METHODS: In a prospective study, the medical and developmental outcome of 439 children born after ICSI (378 singletons, 61 twins) were compared with those of 207 children born after IVF (138 singletons, 69 twins), at the age of 24-28 months. These children were part of a cohort of children followed since birth. Of children reaching the age of 24-28 months between May 1995 and March 2002, 44.3% (2375/5356) were examined by a paediatrician who was unaware of the type of treatment used for each couple. Of all the children born, 12.2% (439/3618) in the ICSI group and 11.9% (207/1738) in the IVF group underwent a formal developmental assessment using the Bayley Scale of Infant Development (mental scale) by a paediatrician blinded to the type of treatment. RESULTS: There was no significant difference in maternal educational level, maternal age, gestational age, parity, birthweight, neonatal complication rate or malformation rate at 2 years between ICSI and IVF singletons, or between ICSI and IVF twins. No significant difference was observed in the developmental outcome using the Bayley scale at the age of 24-28 months (raw scores or test age) between ICSI children or IVF children. A multivariate regression analysis for the singleton children indicated that parity, sex (boys had lower scores than girls) and age had a significant influence on the test result, but that the fertility procedure (ICSI versus IVF) did not influence the test result. ICSI children from fathers with low sperm concentration, low sperm motility or poor morphology had a similar developmental outcome to that of children from fathers with normal sperm parameters. There were no significant differences between the initial cohort and the group lost to follow-up, nor between the psychologically tested and the non-tested group for a number of variables such as maternal educational level, birthweight in singletons and neonatal malformation rate. Although only some of the cohort of ICSI children were evaluated, a representative sample of both ICSI and IVF children was compared. CONCLUSIONS: There is no indication that ICSI children have a lower psychomotor development than IVF children. Paternal risk factors associated with male-factor infertility were found not to play a role in developmental outcome.  相似文献   
50.
In the first experiment, the effects of lesions of (1) the amygdala, (2) its major efferent projection system, the stria terminalis or (3) other non-limbic brain sites on the induction of maternal behavior in the nulliparous female rat were investigated. Animals sustaining lesions of either the amygdala or the stria terminalis became maternal more rapidly than did control animals. In the second study the effects of lesions to different portions of the amygdala on both maternal and fear responding were investigated. It was found that animals sustaining damage to the corticomedial amygdaloid nuclei became maternal more quickly than did animals sustaining either basolateral amygdaloid damage or no amygdaloid damage. Also in comparison to lesioned controls, animals with lesions of the amygdala showed reduced ‘fearfulness’ on a number of fear-mediated tasks. The third study attempted to interrelate fear responsiveness and maternal behavior by observing nulliparous animals with amygdaloid or stria terminalis lesions for their responses to unfamiliar foster pups placed daily into their preferred nesting quadrant. While control animals actively avoided pups placed into their nest sites (by moving their nest site to another quadrant of the cage), animals with amygdaloid lesions or lesions of the stria terminalis, did not. These results are interpreted to mean that nulliparous females generally do not respond maternally to pups because these females are, in general, more neophobic than parturient females and they tend to find pups and their novel odors, aversive. This aspect of their behavior is likely mediated by the amygdala. These data are discussed in terms of their relevance to the rapid maternal responsiveness normally shown by the female at parturition.  相似文献   
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