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31.
Migraine is 3 times more common in postpubertal women than in men. Migraine is frequently exacerbated perimenstrually and commonly occurs exclusively at that time. It is often benefited by pregnancy and menopause. Estrogen withdrawal has been implicated as a mechanism for triggering migraines. The mechanism, however, is not well understood. Reproductive steroids have neuroactive properties that can modulate neuronal morphology and physiology. Increasing evidence suggests that circulating reproductive steroid levels regulate the balance of neuroexcitatory and neuroinhibitory activities in some brain regions by influencing synaptic plasticity. Estrogen has neuroexcitatory, whereas progesterone has neuroinhibitory, effects in most preclinical and clinical models. Several neurotransmitter systems that are implicated in migraine vary with reproductive steroid levels during the reproductive cycle. Estrogen stabilization may provide effective treatment in susceptible women, especially for catamenially exacerbated migraine. 相似文献
32.
目的探讨旋转强恒磁场(RCSMF)对SD大鼠的骨骼生长发育及相关激素的影响,为RCSMF促进人体增高的临床应用奠定基础。方法取25日龄的SD大鼠置RCSMF下,1.5h/d。每5天取血检测大鼠生长激素(GH)、类胰岛素生长因子(IGF-Ⅰ)、雌激素(E2)等与骨骼发育相关的激素,同时测量每组大鼠的身长、体重和尾长,并用骨形态计量学方法研究RCSMF对大鼠骨组织形态学和动态学参数的影响。结果RCSMF处理后大鼠的身长[实验组(25.28±0.41)cm。对照组(24.05±0.35)cm;P〈0.01]、体重[实验组(445.90±16.88)g,对照组(382.22±12.78)g;P〈0.01]、胫骨长[实验组(3.89±0.13)cm,对照组(3.66±0.10)cm;P〈0.01]和股骨长[实验组(3.65±0.08)cm,对照组(3.51±0.06)cm;P〈0.01],上述多项参数以及骨骺板等相关形态计量学数据实验组明显高于对照组。回归分析身长与相关激素的关系显示:大鼠身长与GH、IGF—I和E2有显著相关性。结论RCSMF有促进骨骼生长发育的作用,其作用机理是通过刺激与骨骼生长发育相关激素的生成、释放,并影响软骨细胞的增殖功能来完成的。 相似文献
33.
34.
A. Saija P. Princi R. De Pasquale G. Costa G. B. De Sarro 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1992,88(1):151-157
Summary The genetically epileptic-prone rat (GEPR) is a valuable model for the study of gene-linked abnormalities involved in epilepsy. In comparison with normal Sprague-Dawley controls, we found, in GEPRs, a marked depression in local cerebral glucose utilization, widespread throughout the brain. This depression was accompanied by a significant increase of blood-brain barrier permeability and a reduction in regional blood volume. Finally GEPRs showed lower plasma levels of total triiodothyronine than normal controls. One can speculate that alterations in cerebral metabolism and microvascular regulation and thyroid hormone imbalance may be gene-linked factors involved in seizure susceptibility. 相似文献
35.
D. Caroline Blanchard Jon K. Shepherd R. J. Rodgers Robert J. Blanchard 《Psychopharmacology》1992,106(4):531-539
The Proxemics/Activity test and the Eat/Drink test, two components of the Anxiety/Defense Test Battery, were developed to measure defensive reactions to situations associated with a natural predator (cat). In the present studies the behavioral effects of 8-OH-DPAT treatment (0.01–1.0 mg/kg, SC) were entirely consistent with anxiety/fear reduction. These effects included an increase in time spent near the cat compartment, and a complimentary decrease in time spent farthest from this compartment, together with an increase in transits and locomote behavior. 8-OH-DPAT (1.0 mg/kg) also increased eat frequencies and durations (highly preferred food) both during and following cat presentation, without influencing drinking. This finding is discussed with reference to previous findings with 8-OH-DPAT in studies assessing both food intake and anxiolysis. Interestingly, 8-OH-DPAT was more potent in a majority of its effects in female subjects, a finding consistent with recent neurochemical data. These findings provide important behavioral evidence for a sexual differentiation in 5-HT function, and support the case for greater emphasis on female subjects in animal models of anxiety.Supported by NIH MH42803 and RCMI Grants RR03061 and RR01825 相似文献
36.
Solveig B. Larsen Aleksander Giwercman Marcello Spanò Jens P. Bonde The ASCLEPIOS Study Group 《Reproductive toxicology (Elmsford, N.Y.)》1998,12(6):391-589
It was hypothesized that occupational exposure to pesticides during a spraying season causes changes in semen quality that might be detected in a longitudinal study. We analyzed the within-person changes in semen quality and reproductive hormones across a spraying season in groups of farmers using and not using pesticides. A total of 248 men collected two semen samples (participation rate: 32%). The median sperm concentration declined significantly from the first to the second sample in both groups, but there was no statistical difference in the decline between the two groups, unadjusted or adjusted. Only minor changes were found in sperm morphology, vitality, motility, sperm chromatin denaturation (SCSA), and reproductive hormones, and the differences in changes between the two groups were nonsignificant, or, in the opposite direction to the expected. There was no relation between the changes in sperm parameters in relation to pesticide exposure variables. In conclusion, use of pesticides by Danish farmers is not a likely cause of short-term effects on semen quality and reproductive hormones. 相似文献
37.
Charles J. Meliska Andrzej Bartke Jimmy L. Vandergriff Robert A. Jensen 《Pharmacology, biochemistry, and behavior》1995,50(4):563-570
Transgenic mice overexpressing the phosphoenolpyruvate carboxykinase/bovine growth hormone (PEPCK/ bGH) hybrid gene and normal (nontransgenic) littermate controls (10 males + 10 females/group) were given access to tapwater and an ascending series of concentrations of ethanol (1.0–22.0%), then a similar ascending series of concentrations of nicotine (1.0–40.0 μg/ml), in a two-bottle choice test. Male transgenic mice consumed more and exhibited greater preferences for ethanol and nicotine than control males; transgenic females consumed less and showed lower preferences for ethanol, but not nicotine, than control females. These results suggest that chronic exposure to high levels of bGH may modulate the rewarding effects of ethanol and nicotine in mice in a gender-specific fashion. 相似文献
38.
超声引导下注射皮质类固醇治疗狭窄性腱鞘炎 总被引:1,自引:0,他引:1
目的 探讨超声引导下注射皮质类固醇治疗狭窄性腱鞘炎的方法及效果。方法 38例狭窄性腱鞘炎患者,按药物注射方法的不同随机分成2组。治疗组(21例)在10-MHz超声引导下向腱鞘内腱周间隙内穿刺注射醋酸强的松龙0.6 ml,对照组(17例)采用闭合穿刺法注射等量药物。注射前及随访时(注射后3周)测定疼痛强度视觉类比评分(Visual analogue score,VAS)。结果 随访时疼痛消失率治疗组为81%、对照组为53%,VAS下降值治疗组为[(6.8±1.9)x±s,下同]对照组为(5.1±3.0)。结论超声引导下将针尖穿刺于腱鞘内腱周间隙的操作简单、准确并可实时观察药物的分布,是治疗狭窄性腱鞘炎的较好方法。 相似文献
39.
目的:测定妊高征患者血清睾酮水平并探讨其临床意义。方法:采用放射免疫分析法测定妊高征患者30例、正常孕妇20例血清及其新生儿脐血睾酮水平。结果:妊高征患者血清睾酮水平(0.153±0.078nmol/L)明显高于正常孕妇组(0.023±0.015nmol/L),有显著性差异(P<0.001)。妊高征组脐血睾酮水平(0.052±0.041nmol/L)低于正常孕妇组(0.119±0.059nmol/L),有显著性差异(P<0.05),两组睾酮水平与新生儿性别无关(P>0.05)。结论:孕妇血清睾酮在妊高征的病理生理中起调节或加强作用。 相似文献
40.
Ikuo Konishi 《Medical Electron Microscopy》1994,27(3-4):271-274
The developmental relationship between granulosa and stromal cells in the fetal ovary was reviewed. The proliferation and
expression of basic fibroblast growth factor (bFGF) and luteinizing hormone receptor (LHR) of both the granulosa and theca
cells was examined in the adult ovary. Ovarian granulosa cell tumors were then studied under light and electron microscopy
and for immunohistochemical expression of bFGF and LHR. In the follicular development of the adult ovary, bFGF expression
in the granulosa cells was correlated with theca cell proliferation. In ovarian granulosa cell tumors, estrogen-producing
tumors showed a stratified or microfollicular pattern being accompanied by theca cells which had ultrastructural features
of steroid-production, and these tumor cells exhibited immunoreactivity for bFGF. In contrast, tumors with no apparent hormone-production
showed a solid or gyriform pattern without admixture of theca cells, and were negative for bFGF. LHR was expressed in both
types of tumor. Accordingly, bFGF may play an important role in association with the theca cell component in granulosa cell
tumors. 相似文献