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71.
低剂量阿司匹林在辅助生育技术中的应用 总被引:2,自引:0,他引:2
目的 探讨在进行体外受精 -胚胎移植 ( IVF-ET)或卵母细胞浆内单精子注射 ( ICSI)患者口服低剂量阿司匹林对治疗结果的影响。 方法 IVF或 ICSI治疗的 3 2 4个 ET周期 ,分为是否服用阿司匹林两组 ,分别统计患者注射人绒毛膜促性腺激素 ( h CG)时子宫内膜厚度及 ET胚胎数 ,比较两组的胚胎种植率、临床妊娠率及流产率 ,并进行统计学处理。 结果 两组在注射 h CG日内膜平均厚度、ET中优质胚胎的比率及流产率均无显著性差异 ;未服用阿司匹林组的 ET胚胎数明显多于服用组 ( P<0 .0 1 ) ,而前者的种植率、临床妊娠率却明显低于后者 ( P<0 .0 1 )。 结论 低剂量阿司匹林在 IVF-ET或ICSI的辅助生殖治疗中能有效地提高胚胎种植率 ,增加患者的临床妊娠率 相似文献
72.
Previously, we determined the pattern of stress-induced c-fos mRNA expression throughout the brain in order to gain further insight into the identification of the neural circuits mediating stress-induced regulation of the hypothalamic-pituitary-adrenal axis. In the present study, we determined if rapid effects of increased glucocorticoid levels after stress contribute to changes in c-fos mRNA expression. To this end, stress-induced c-fos expression was characterized in adrenalectomized (ADX) or adrenalectomized and corticosterone replaced (ADX/B) male rats. Animals were sacrificed 30 min post-onset of a 10 min swim stress, and in situ hybridization histochemistry was used to detect c-fos mRNA throughout the brain. The pattern of c-fos induction in the ADX and ADX/B animals was similar to that observed in the sham operated animals. Additionally, densitometric measurements were made to quantify the c-fos response in the paraventricular nucleus of the hypothalamus and the CA1/2 region of the hippocampus. We found that ADX did not alter the magnitude of the c-fos response to stress in these areas, but there was a slight dampening of the response in ADX/B animals. In sum, these results suggest that the pattern of c-fos expression observed 30 min post-stress is independent of stress-induced increases in circulating glucocorticoid concentrations. 相似文献
73.
阴道毛滴虫代谢产物体外对精子活力的影响 总被引:1,自引:0,他引:1
目的 :研究阴道毛滴虫代谢产物体外对人精子活力的影响。 方法 :阴道毛滴虫体外培养 ,除去虫体 ,留取培养液 ,稀释成三个浓度 ;将 10例正常生育男性的优化精子分为等体积的 4份 ,组成以下 4组 :A组加入未培养滴虫的空白培养液 ,B ,C ,D组依次加入前述浓度梯度的培养液 (1.2× 10 9/L、6× 10 8/L、1.2× 10 8/L) ,分别于 30s、1、2、4和 6h时采用计算机辅助精子分析系统 (CASA)分析精子运动参数。 结果 :阴道毛滴虫浓度在 6× 10 8/L以上时 ,精子的活率和活力与对照组相比都显著降低 (P <0 .0 5 ) ,并呈浓度依赖性和时间依赖性。 结论 :阴道毛滴虫代谢产物体外能抑制精子活力 ,可能是造成不孕不育的原因之一。 相似文献
74.
氯喹敏感与抗性株恶性疟原虫对青蒿琥酯、克林霉素及其联用的体外敏感性 总被引:3,自引:0,他引:3
目的 为了解氯喹敏感和抗性株恶性疟原虫对青蒿琥酯、克林霉素及其二联用的敏感性。方法 运用Rieckmann体外微量法测定原虫对药物的敏感性。结果 氯喹敏感株恶性疟原虫对青蒿琥酯、克林霉素及青/克联用的ID50分别为2.8、3784.7及6.4/2046.6nmol/L;抗性株原虫对上述药物的ID50分别为8.1、1652.1及2.35/1409.4nmol/L。结论 抗氯喹恶性疟原虫对克林霉素无交叉抗性。青蒿琥酯与克林霉素联用在体外测定中,其抗疟作用对抗性株明显优于敏感株。 相似文献
75.
目的:以原位杂交法检测PPL13在人胎盘组织的表达情况。方法:用DIG标记的PPL13有义RNA探针及反义RNA探针与胎盘组织切片进行原位杂交。结果:反义RNA探针杂交标本显色3h,显微镜下可见胎盘毛细血管内皮细胞中出现棕色沉淀物,滋养层细胞中未见棕色沉淀物;而有义RNA探针杂交标本显色24h仍无棕色沉淀物出现。结论:PPL13在人胎盘内皮细胞中特异性表达.提示PPL13可能与胎盘的屏障作用有关。 相似文献
76.
人脐血中血管内皮祖细胞体外扩增和鉴定的实验研究 总被引:7,自引:0,他引:7
目的:探讨从人脐血中分离、培养、体外扩增血管内皮祖细胞(EPC)的方法及体外进行EPC的鉴定。方法:采用密度梯度离心法从脐血中分离EPC,体外分别培养在包被有FN和不包被FN的培养皿中,采用免疫组织化学技术(SABC法)鉴定培养贴壁细胞表面标志CD31、CD34及KDR的表达;流式细胞仪检测细胞表面标志CD133及表达CD133细胞比例。结果:包被FN的培养皿中细胞贴壁及增殖均比未包被的多,免疫组化染色CD31、CD34及KDR均呈阳性,培养第4天流式细胞仪检测CD133^ 占21.3%。结论:密度梯度离心法可用于体外分离脐血中EPC进行实验研究,FN对于体外培养EPC有非常重要的作用。 相似文献
77.
Integrated plasma cortisol concentration in children with asthma receiving long-term inhaled corticosteroids. 总被引:2,自引:0,他引:2
We assessed the effect of long-term therapy with inhaled beclomethasone dipropionate (BDP) on the pituitary-adrenal axis, by measuring the integrated concentration (IC) of plasma cortisol in eight children with asthma (age, 6-16 years) who regularly used inhaled BDP in doses ranging from 8 to 26.5 micrograms/kg (200-450 micrograms/day) for 6 months to 4 years. The control group included six children (age, 6-16 years) who had the IC of plasma cortisol measured as part of an endocrinological evaluation and were found to be healthy. Cortisol concentration was measured in blood samples collected continuously over a 24-hr period. Mean IC of plasma cortisol in the study group was significantly lower than in the healthy controls (mean +/- SD, 4.9 +/- 3.3 vs 9.1 +/- 1.9 micrograms/mL; P less than 0.02). Cortisol response to 0.25 mg ACTH (iv) was abnormal in one of the eight BDP-treated patients. No correlation was found between IC of plasma cortisol and the BDP dose, severity of asthma, height percentile, or the Tanner stage. We conclude that long-term therapy, even with relatively conventional doses of inhaled BDP may cause reduction in the normal physiological secretion of cortisol. The clinical relevance of low IC of plasma cortisol is not clear, but it may reflect partial suppression of the pituitary-adrenal axis. 相似文献
78.
N. R. Saunders A. Deal G. W. Knott Z. M. Varga† J. G. Nicholls † 《Clinical and experimental pharmacology & physiology》1995,22(8):518-526
1. Repair and recovery following spinal cord injury (complete spinal cord crush) has been studied in vitro in neonatal opossum (Monodelphis domestica), fetal rat and in vivo in neonatal opossum. 2. Crush injury of the cultured spinal cord of isolated entire central nervous system (CNS) of neonatal opossum (P4–10) or fetal rats (E15–E16) was followed by profuse growth of fibres and recovery of conduction of impulses through the crush. Previous studies of injured immature mammalian spinal cord have described fibre growth occurring only around the lesion, unless implanted with fetal CNS. 3. The period during which successful growth occurred in response to a crush is developmentally regulated. No such growth was obtained after P12 in spinal cords crushed in vitro at the level of C7–8. 4. In vivo, in the neonatal (P4–8) marsupial opossum, growth of fibres through, and restoration of, impulse conduction across the crush was apparent 1–2 weeks after injury. With longer periods of time after crushing a considerable degree of normal locomotor function developed. 5. By the time the operated animals reached adulthood, the morphological structure of the spinal cord, both in the region of the crush and on either side of the site of the lesion, appeared grossly normal. 6. The results are discussed in relation to the eventual longterm possibility of devising effective treatments for patients with spinal cord injuries. 相似文献
79.
Catalina Betancur Carmen Sandi Sergio Vitiello Jos Borrell Carmen Guaza Pierre J. Neveu 《Brain research》1992,589(2):302-306
Asymmetry in brain modulation of the immune system has been previously described. In mice, paw preference has been shown to be associated with immune reactivity but the mechanisms involved in such an association are not yet known. The autonomic nervous system and the neuroendocrine system are considered as major candidates for neural influences on the immune system. In the present study, the activity of the hypothalamic-pituitary-adrenal (HPA) axis of adult female mice selected for paw preference (left-handers vs. right-handers) was assessed by measuring both adrenocorticotropic hormone (ACTH) and corticosterone plasma levels, as well as the in vitro responses of hypothalamus and adrenocortical cells to various hormone releasing stimuli. The results reported here showed no difference in the activity of the HPA axis between left- and right-handed mice, suggesting that this neuroendocrine axis is not implicated in the association between functional brain asymmetry and immune reactivity. However, our results do not exclude the possibility that the HPA axis could play a role in such an association under other circumstances, such as during development or stressful situations. 相似文献
80.
The characteristics and distribution of muscarinic acetylcholine (mACh) receptor binding in primary somatosensory (SI) cortex and the caudate nucleus of raccoons were studied using [3H]-QNB, a muscarinic antagonist. The binding characteristics were similar to reported values in rat and cat. Autoradiographs produced from tissue sections labeled with [3H]-QNB showed the distribution of mACh receptors in the forebrain of the raccoon. [3H]-QNB binding was highest in cerebral cortex, neostriatum and hippocampus. Within SI cortex, binding was high in layers I-III and VI and relatively low in layers IV and V. Autoradiographs obtained from animals that had undergone peripheral deafferentation of part of the forepaw revealed no changes in [3H]-QNB binding in the affected cortical region during the time that physiological reorganization is known to occur. 相似文献