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1.
孕妇血清AFP、uE3和β-hCG水平与严重胎儿缺陷的关系   总被引:3,自引:0,他引:3  
①目的 探讨孕中期血清甲胎球蛋白(AFP),游离雌三醇(uF3)和β绒毛膜促性腺激素(β-HCG)水平与严重胎儿缺陷的关系。②方法 用ELISA方法对832例16-21周妊娠妇女血清AFP、UE3和β-hCG进行检测,以筛查阳性病人。③结果 14例胎儿被确诊为异常,其中唐氏综征2例,无脑儿3例,脊柱裂3例,唇腭裂1例,腹裂肠外翻1例,孕中期自然流产2例,死胎1例,葡萄胎1例,总检出率为1.68%,假阳性15例,占被检人数的1.80%。④结论 以上3种生化指标联合检测可作为产前诊断严重胎儿缺陷的有效方法。  相似文献   
2.
Testicular seminoma with elevated serum human chorionic gonadotropin level (hCG-positive seminoma) is regarded as more malignant than marker-negative seminoma, although Its prognosis is still unclear. To clarify the malignant potential of seminoma with hCG production, the serum levels of the beta subunit of hCG (β-hCG) and lactic acid dehydrogenase (LDH) were examined in 35 and 40 patients, respectively, and the Immunohistochemical expression of β-hCG examined in 45 tumors. The elevation of the LDH serum level correlated to the Invasive status, metestatic status and poor outcome, while that of the serum β-hCG level correlated only to the metastatic status. Immunohistochemical expression of β-hCG was observed in syncytiotrophoblastic giant cells in 11 tumors and a few mononuclear seminoma cells In 36 tumors. Expression was not associated with the malignancy potential, except where the expression In mononuclear cells Inversely correlated to the invasive status. These results suggest that most seminomas produce a slight amount of hCG; that an elevated hCG serum level Indicates the pressnce of metastatic tumors and mainly reflects an increase in tumor volume but not in cellular malignancy potential; and that the LDH serum level, rather than hCG, is more useful as a prognostic indicator for patients with seminoma.  相似文献   
3.
Purpose: Our purpose was to examine implantation of singleton pregnancies achieved following various assisted reproductive technologies (ARTs) through the appearance and rising titers of serum human chorionic gonadotropin (hCG) levels. Methods: A total of 114 singleton pregnancies resulting from in vitro fertilization and intrauterine insemination was analyzed. Patients were divided into five groups according to the type of ovarian stimulation protocol [gonadotropin stimulation with/without the use of gonadotropin-releasing hormone agonist (GnRHa), long protocol, or flare-up technique] and to the day of embryo transfer (day 2 or day 3 after oocyte retrieval). Serial serum hCG levels were measured between 10 and 25 days after fertilization and log-transformed. Linear regression analyses were performed and extrapolated to hCG = 10 mIU/ml (hCG 10 ), which was used as an estimate of detectable implantation. The slopes of the regression lines were used to estimate the rising speed of hCG. Results: There were no significant differences in the days of hCG in maternal serum to reach 10 mIU/ml (implantation) or in the slopes of the regression lines for all five studied groups. Conclusions: The appearance of hCG in maternal serum was used to assess the time of clinically detectable implantation. Furthermore, because hCG production is a marker of trophoblastic activity, its serum doubling time was used as an indicator of embryo quality. Results showed that in various ART protocols with and without GnRHa, there were no significant differences in implantation time or embryo quality. Embryo development in early pregnancy follows a preprogrammed-timing schedule and depends mainly on the embryonic age of the health, successfully implanted conceptus.  相似文献   
4.
The effects of gonadal steroids on GABA-, taurine (TAU)- and N-methyl-D, L-aspartate (NMA)-induced gonadotropin-II (GTH-II) release were investigated in male and female goldfish in vivo. In sexually regressed goldfish (both sexes mixed), intraperitoneal implantation for 5 to 10 days with solid Silastic pellets containing testosterone (100 μg/g), oestradiol (100 μg/g) or progesterone (100 μg/g) was previously shown to elevate serum sex steroid levels to values comparable to those in sexually mature animals, and to potentiate gonadotropin-releasing hormone-stimulated GTH-II release. In the present study, testosterone but not oestradiol or progesterone enhanced the stimulatory effects of exogenous GABA (100 μg/g) on GTH-II release in vivo. TAU (1 mg/g) stimulated GTH-II release in sexually regressed mixed sex and sexually recrudescent male goldfish, and both testosterone and oestradiol implantation enhanced GTH-II release induced by TAU. The glutamate agonist NMA (25 to 50 μg/g) was also found to stimulate GTH-II release; however it was relatively less effective in elevating serum GTH-II levels than GABA and TAU, and its effects were not modulated by sex steroid treatments. Pretreatment of goldfish with α-methyl-p-tyrosine to deplete brain and pituitary catecholam-ines did not affect NMA action on GTH-II release. Our results indicate that GABA, TAU and NMA are involved in the neuroendocrine regulation of GTH-II release in goldfish, and support the idea that testosterone participates in the positive feedback regulation of pituitary gonadotropin release in a non-mammalian vertebrate by enhancing GABA- and TAU-stimulated GTH release in vivo.  相似文献   
5.
用荧光原位杂交技术快速诊断孕早期胚胎染色体数目异常   总被引:4,自引:1,他引:3  
目的探讨荧光原位杂交(FISH)技术在快速产前诊断孕早期胚胎染色体数目异常中的价值.方法采用13,18,21,X和Y染色体特异性DNA探针,对46例孕47~65 d高危孕妇的绒毛间期细胞进行FISH检测,同时行常规染色体核型分析平行诊断.结果与染色体核型分析结果一致的染色体数目正常43例,异常3例(47,XY 21;47,XY 18和45,X).3例异常核型胚胎经治疗性流产后再分别对其绒毛行常规染色体核型分析,结果与产前诊断相符.结论FISH技术用于产前诊断孕早期胚胎染色体数目异常具有快速、准确等优点.  相似文献   
6.
以分离的细胞膜为受体制剂,对大鼠卵巢及睾丸人绒毛膜促性腺激素(HCG)受体进行比较研究,发现二者的受体结合特性有一定差异;同时将大鼠寒丸膜及睾丸匀浆作对比,友现睾丸膜制剂较睾丸匀浆更能准确地体现睾丸HCG受体的真正特性。  相似文献   
7.
胶体金免疫层析法检测尿hCG的质量控制方法探讨   总被引:1,自引:0,他引:1  
王梅  康红  李月 《西部医学》2005,17(6):643-644
目的通过对胶体金免疫层析法(GICA)试纸条评价,建立该方法的检测尿hCG的室内质控.方法利用hCG不同浓度的标准品评价试纸条的敏感性、重复性、稳定性、检测范围,检测温度及时间对试纸条检测尿hCG结果的影响等.结果GICA的检测范围25-100万mlU/ml,最低检出限达25mIU/ml,大于200万mIU/ml时存在后带现象.试纸条反应5分钟后呈色均一,最佳检测温度为4-30℃.结论灵敏度检测可作为GICA室内质控的主要指标,它能保证检测结果的准确性.  相似文献   
8.
人绒毛膜促性腺激素在脑实质生殖细胞肿瘤诊治中的意义   总被引:2,自引:1,他引:1  
目的研究脑实质生殖细胞肿瘤(GCT)患者脑脊液和血清中人绒毛膜促性腺激素(HCG)水平变化,评价其在肿瘤诊断、疗效监测中的意义。方法对5例脑实质内GCT患者的脑脊液和血清HCG水平在治疗前后进行系列测定。以10例性别年龄匹配的因其他疾病接受腰穿检查的患者作为对照组,测定其脑脊液HCG水平。观察脑脊液和血清HCG水平在治疗前后的变化情况。结果10例对照组患者的脑脊液中均测不到HCG。从5例GCT患者共采集17对脑脊液和血清配对样本。所有5例患者都出现脑脊液和血清HCG水平升高。治疗后脑脊液和血清HCG水平迅速下降。血清和脑脊液HCG水平呈显著相关。每一对样本中,脑脊液HCG水平均高于血清。血清、脑脊液HCG水平比为0.245±0.190。结论脑脊液HCG升高对诊断脑实质内GCT具有高度特异性和较高灵敏度。对分泌HCG的GCT,脑脊液和血清HCG是评价治疗效果和监测肿瘤复发的重要指标。  相似文献   
9.
This review focuses on estrogen role on human male physiology. Biological estrogen actions on male reproductive system are summarized with particular regard to the effects of congenital estrogen deprivation in men. The effects of estrogen on spermatogenesis, hormonal secretion and gonadotropin feedback and on sexual behavior are discussed. It is remarked that the role of estrogens in male reproduction is a very recent acquisition in reproductive endocrinology, but it promises new future fields of research to be investigated as well as the possible disclosure of new strategies in clinical practice.  相似文献   
10.
Objective:To evaluate the feasibility and safety of prenatal diagnosis by traneabdominal chorionic villus sam-pling(TA-CVS)via the guidance of B-mode ultrasound in the first trimester of gestation.To explore the technique of long time culture and chromosome preparation of villi in early pregnancy.To evaluate the feasibility of the above techniques in the application of the prenatal cytogenetic diagnosis.Methods:One hundred and thirty-five singleton pregnancies at risk were referred from January 2001 to Decem-ber 2007.Results:The average maternal age was 35.2 years.TA-CVS was performed in the 10~13th weeks of gestation and the average gestational age was 10.89 weeks.All attempts at sampling were successful.The rate of operation-associated fetal loss was 0.74%.The failure rate of prenatal diagnosis because of inadequate amount of specimen was 0.The average culture time was 5-7 days.The success rate of the cell culture was 98.5%.No maternal con-temination and bacterial contamination happened.Fifteen cases of abnormal karyotype and one case of confined pla-cantel mosaiciem were diagnosed.Conclusion:TA-CVS appears to be safe and feasible and might to be offered in the prenatal diagnosis in the first trimester of gestation.The technique of long time culture and chromosome preparation of villi is stable and reliable.It is feasible to apply these techniques in the clinical practice of prenatal cytogenetic diagnose in the early pregnancy.  相似文献   
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