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71.
Previous work has shown that rate of extinction of a conditioned taste aversion is affected by concurrent levels of testosterone in adult rats. In the present study, castrated male and female adult rates were given either oil or testosterone during acquisition of the conditioned taste aversion and then either oil or testosterone during extinction. The males and females that received testosterone during the extinction of the aversion showed the slower, masculine rate of extinction regardless of the type of injections they received during acquisition. Conversely, the animals that received oil during extinction showed the faster, feminine rate of extinction regardless of the type of injection during acquisition. In light of these findings, a number of alternative behavioral changes that could account for the effect of testosterone on the rate of extinction were evaluated. 相似文献
72.
Adult male and female Wistar rats maintained on ad lib diet were given a choice between tap water and a solution of glucose in the concentration of either 5 or 12%. Both sexes exhibited a marked preference for glucose solutions. With the 5% solution the volume intake was similar in both sexes and the total calorie intake was normal. With the 12% solution the volume intake was higher in females than in males, while in both sexes the total calorie intake was increased to a similar (maximum acceptable) level. Treatment with Protamine Zinc Insulin (PZI) in a daily dose of 40 U/kg b.w. markedly increased the intake of the 5% solution in both sexes, but significantly more in females than in males, thus revealing sex differences which were not manifest in untreated rats. PZI treatment had little effect on 12% glucose solution intake, presumably because with this solution the total calorie intake was increased to a maximum already in untreated rats. 相似文献
73.
目的:分析桥本氏甲状腺炎(HT)在不同年龄男女性患者分布差异及相关抗体水平变化特点。方法:2014-01-01—2018-12-31五年间本院收治的HT患者共2705例,先按年龄分为儿童组(n=32)、青春期组(n=135)和成人组(n=2538),再将成人组中女性分为≤50岁组(n=1645)及>50岁组(n=519)两组,比较不同年龄组HT男女性占比差异,分析不同年龄组以及50岁前后女性甲状腺过氧化物酶抗体(TPOAb)和甲状腺球蛋白抗体(TgAb)的水平变化。结果:在三年龄组中,HT总病例数以成人组最多,儿童组较少。各年龄组间男性、女性HT占比差异有统计学意义(P<0.01);各年龄组内女性占比均显著高于男性,尤以成人组女性占比最高(P<0.01)。三年龄组间TPOAb、TgAb水平有显著统计学意义(均P<0.01)。青春期组及成人组TPOAb水平均低于儿童组(P<0.01),成人组与青春期组TPOAb水平差异无统计学意义(P>0.05);青春期组TgAb水平低于儿童组(P<0.01),儿童组与成人组间、青春期组与成人组间TgAb水平的差异均无统计学意义(P>0.05)。≤50岁与>50岁女性的TPOAb和TgAb水平比较均无统计学差异(P>0.05)。结论:成年人(>18岁)HT明显多于非成年人,且女性占比显著高于男性。TPOAb下降可能是成人HT的内分泌影响因素之一。 相似文献
74.
Sexually experienced male rats were used to test the attractiveness of body odors of female rats. The attractiveness of these odors varied with the estrous cycle. Odors from female rats in proestrus were the most attractive to male rats and those from female rats during the darkness hours of diestrus the least attractive. The preputial glands appeared to be the source of these odors for the male rats showed no preference for the odors of proestrous female rats that had been preputialectomized. Administration of 1 μg estrdiol benzoate (EB) for 5 days increased the attractiveness of body odors of ovariectomized rats. A higher dose of EB (5 μg) had the same effect when administered for 1 or 5 days although the increase that occurred after 3 days was not significant. A single dose of progesterone (P) (500 μg) on the other hand, decreased the attractiveness of ovariectomized female odors although no change was seen after 3 days of treatment. A single injection of P also decreased the attractiveness of odors of ovariectomized females that had received EB for 3 days. However, P failed to decrease the attractiveness of odors in ovariectomized females after preputialectomy. We conclude that the preputial glands are an important source of sex attractant odors in the female rat and that the changes in the release of these odors that occur throughout the estrous cycle and pregnancy are controlled by ovarian steroids. While estrogen acts to stimulate the production and release of these odors P appears to inhibit their release. 相似文献
75.
Bang AK Carlsen E Holm M Petersen JH Skakkebaek NE Jørgensen N 《Human reproduction (Oxford, England)》2005,20(11):3109-3113
BACKGROUND: It has been suggested that finger length may correlate with function or disorders of the male reproductive system. This is based on the HOXA and HOXD genes' common embryological control of finger development and differentiation of the genital bud. The objective of this study was to explore the association between the ratio of 2nd to 4th finger length (2D:4D ratio) and testis function in a sample of young Danish men from the general population. METHODS: Semen samples and finger measurements were obtained from a total of 360 young Danish men in addition to blood samples for sex hormone analysis to describe the possible association between 2D:4D and semen and sex-hormone parameters. RESULTS: A statistically significant inverse association with the 2D:4D was found only in relation to hormone levels of FSH in the group of young men with a 2D:4D >1 (P = 0.036) and a direct association with the total sperm count in the group of young men with a 2D:4D < or = 1 (P = 0.045). CONCLUSION: The statistically significant results may be 'false positives' (type I error) rather than representing true associations. This relatively large study of young, normal Danish men shows no reliable association between 2D:4D finger ratio and testicular function. Measurements of finger lengths do not have the power to predict the testicular function of adult men. 相似文献
76.
K. Andersson K. Fuxe P. Eneroth L. F. Agnati A. Härfstrand 《Naunyn-Schmiedeberg's archives of pharmacology》1987,335(5):521-528
Summary The effects of acute continuous exposure to the smoke from 1–4 cigarettes have been studied in the male rat in terms of hypothalamic catecholamine levels and utilization as well as the secretion of anterior pituitary hormones. Catecholamine levels in discrete hypothalamic catecholamine nerve terminal systems were studied by quantitative histofluorimetry. Catecholamine utilization was studied by means of the tyrosine hydroxylase inhibition method using -methyl-(±)-p-tyrosine methyl ester. The serum hormone levels of adenohypophyseal hormones and of corticosterone were measured by the use of radioimmunoassay procedures. The results show that acute continuous exposure to unfiltered but not to filtered (Cambridge glass fibre filters) cigarette smoke leads to small but dose-dependent reductions of amine levels in most of the hypothalamic noradrenaline and dopamine nerve terminal system. These effects were associated with an enhancement of regional hypothalamic noradrenaline utilization but not of dopamine utilization in the median eminence. Furthermore, a reduction of TSH and prolactin serum levels was noted as well as increases in ACTH secretion. These results are partly different from those previously obtained with rats acutely exposed to intermittent unfiltered cigarrete smoke. This difference is suggested to be due to a temporary blockade of catecholamine release following acute continuous exposure to cigarette smoke.This work has been supported by a grant (1223) from the Council for Tobacco Research, New York, USA and by a grant from the Svenska Tobaks monopolet
Send offprint requests to K. Andersson at the above address 相似文献
77.
78.
Yoonyoung Jang Yoon-Jung Choi Youn-Hee Lim Kyung-Shin Lee Bung-Nyun Kim Choong Ho Shin Young Ah Lee Johanna Inhyang Kim Yun-Chul Hong 《Yebang Ŭihakhoe chi》2021,54(1):37
ObjectivesBisphenol A (BPA) is used in the electrical, mechanical, medical, and food industries. Previous studies have suggested that BPA is an endocrine disruptor. Regulation of BPA has led to increased use of bisphenol F (BPF) and bisphenol S (BPS). However, few studies have investigated the associations of BPF and BPS with thyroid dysfunction in children. Our study investigated the associations of prenatal BPA and early childhood BPA, BPF, and BPS exposure with thyroid function in 6-year-old children.MethodsPrenatal BPA concentrations were measured during the second trimester of pregnancy in an established prospective birth cohort. We measured urinary BPA, BPF, and BPS concentrations and thyroid hormone levels (thyroid-stimulating hormone, total T3, and free T4) in 6-year-old children (n=574). We examined the associations between urinary bisphenol concentrations and percentage change of thyroid hormone concentrations using multivariate linear regression. We also compared thyroid hormone levels by dividing the cohort according to BPA, BPF, and BPS concentrations.ResultsThe associations between prenatal BPA and total T3 levels were statistically significant in all models, except for girls when using a crude model. The associations between urinary BPA and BPS concentrations and levels of all thyroid hormones were not statistically significant. However, we observed that lower free T4 levels (−1.94%; 95% confidence interval, −3.82 to −0.03) were associated with higher urinary BPF concentrations in girls only.ConclusionsOur findings identified significant associations between prenatal BPA exposure and total T3 levels in all children and between BPF exposure and free T4 levels in girls only. 相似文献
79.
Habeeb Alhabeeb Ali AlFaiz Emad Kutbi Dayel AlShahrani Abdullah Alsuhail Saleh AlRajhi Nemer Alotaibi Khalid Alotaibi Saad AlAmri Saleh Alghamdi Naji AlJohani 《Nutrients》2021,13(2)
We are currently facing an obesity pandemic, with worldwide obesity rates having tripled since 1975. Obesity is one of the main risk factors for the development of non-communicable diseases, which are now the leading cause of death worldwide. This calls for urgent action towards understanding the underlying mechanisms behind the development of obesity as well as developing more effective treatments and interventions. Appetite is carefully regulated in humans via the interaction between the central nervous system and peripheral hormones. This involves a delicate balance in external stimuli, circulating satiating and appetite stimulating hormones, and correct functioning of neuronal signals. Any changes in this equilibrium can lead to an imbalance in energy intake versus expenditure, which often leads to overeating, and potentially weight gain resulting in overweight or obesity. Several lines of research have shown imbalances in gut hormones are found in those who are overweight or obese, which may be contributing to their condition. Therefore, this review examines the evidence for targeting gut hormones in the treatment of obesity by discussing how their dysregulation influences food intake, the potential possibility of altering the circulating levels of these hormones for treating obesity, as well as the role of short chain fatty acids and protein as novel treatments. 相似文献
80.
Bariatric surgery is an effective intervention for management of obesity through treating dysregulated appetite and achieving long-term weight loss maintenance. Moreover, significant changes in glucose homeostasis are observed after bariatric surgery including, in some cases, type 2 diabetes remission from the early postoperative period and postprandial hypoglycaemia. Levels of a number of gut hormones are dramatically increased from the early period after Roux-en-Y gastric bypass and sleeve gastrectomy—the two most commonly performed bariatric procedures—and they have been suggested as important mediators of the observed changes in eating behaviour and glucose homeostasis postoperatively. In this review, we summarise the current evidence from human studies on the alterations of gut hormones after bariatric surgery and their impact on clinical outcomes postoperatively. Studies which assess the role of gut hormones after bariatric surgery on food intake, hunger, satiety and glucose homeostasis through octreotide use (a non-specific inhibitor of gut hormone secretion) as well as with exendin 9–39 (a specific glucagon-like peptide-1 receptor antagonist) are reviewed. The potential use of gut hormones as biomarkers of successful outcomes of bariatric surgery is also evaluated. 相似文献