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41.
In vivo and in vitro studies with different parts of the epididymis and vas deferens were carried out to determine their inherent capacity to synthesize steroids and to correlate with the endogenous levels with or without the administration of hCG.
Incubation with 14C-labelled pregnenolone and testosterone demonstrated that caput epididymidis was more active than other parts in synthesizing testosterone from 14C-pregnenolone and in converting labelled testosterone to 5α-dihydrotestosterone (DHT). The cauda epididymidis and vas deferens accumulated more radioactivity in progesterone and dehydroepiandrosterone (DHEA) than the caput epididymidis.
The levels of DHT, testosterone and 4-androstene-3,17-dione in the caput epididymidis were reduced after ligation of ipselateral efferent ductules indicating the testicular origin of these steroids. The cauda epididymidis and vas deferens had higher levels of progesterone as compared to the other regions of the epididymis, which were decreased after the ligation. Intravenous injection of hCG increased the levels of oestradiol-17β in all tissues and markedly in the cauda epididymidis and vas deferens. The high levels of progesterone and oestradiol-17β present in these organs may be of importance in maintaining fertilizing ability of spermatozoa stored in the cauda epididymidis and vas deferens and their transport.  相似文献   
42.
OBJECTIVE: The lowest effective hCG dose in high responders during IVF-embryo transfer (ET) has not been established. This study was performed to confirm that a dose of 3,300 IU is sufficient to provide adequate oocyte maturation and fertilization. DESIGN: Retrospective review of IVF clinical data. SETTING: Infertility center at a tertiary care university. PATIENT(S): Ninety-four IVF cycles were analyzed from high responders based on peak E(2) levels. Demographics were compared including age, diagnosis, and stimulation protocol. INTERVENTION(S): On the day of hCG administration, if E(2) levels were >/=2,500 but <4,000 pg/mL, patients received 5,000 IU (group A). For levels between 4,000 pg/mL and 5,500 IU pg/mL, they received 3,300 IU (group B). MAIN OUTCOME MEASURE(S): Number of oocytes retrieved, proportion of mature oocytes, fertilization rates, chemical and clinical pregnancy rates (PR). The incidence and severity of ovarian hyperstimulation syndrome (OHSS) was also analyzed. RESULT(S): Mean ages were 35.4 +/- 0.7 and 33.2 +/- 0.7 for groups A and B, respectively. Peak E(2) levels differed significantly (2,907 +/- 76 vs. 4,260 +/- 129 pg/mL), as well as the mean number of eggs retrieved (15.9 +/- 0.9 vs. 20.3 +/- 1.2). Proportion of mature eggs (81.6% vs. 81.9%), fertilization rate (70.5% vs. 68.7%), chemical PR (58.7% vs. 58.7%), and clinical PR (50.0% vs. 43.5%) were similar. There was no difference in the incidence of mild, moderate, or severe OHSS. CONCLUSION(S): A reduced hCG dose of 3,300 IU results in a similar proportion of mature eggs, similar fertilization rates, and similar PRs compared to 5,000 IU. Reducing the dose of hCG does not eliminate the risk of OHSS in a high-risk group.  相似文献   
43.
OBJECTIVE: To confirm that hCG levels in follicular fluid and serum would be comparable between i.m. and s.c. administration of purified hCG. DESIGN: In a prospective study, serum and follicular fluid levels of hCG after an i.m. or s.c. injection of 10,000 IU of hCG were evaluated 36 hours after injection, that is, at the time of oocyte retrieval. SETTING: This study was carried out in a university-affiliated IVF program. PATIENT(S): Forty women undergoing oocyte retrieval were entered into the study at the time of egg retrieval, that is, 36 hours after hCG administration. INTERVENTION(S): S.c. or i.m. injection of hCG. MAIN OUTCOME MEASURE(S): Serum and follicular fluid concentrations of hCG were evaluated 36 hours after injection at the time of oocyte retrieval. RESULT(S): There was a significantly higher serum hCG level in the s.c. group (348.6 +/- 98 IU/L) vs. the i.m. group (259.0 +/- 115 IU/L) and a significantly higher follicular fluid hCG level in the s.c. vs. the i.m. group (233.5 +/- 85 vs. 143.4 +/- 134 IU/L). CONCLUSION(S): After purified hCG administration via the s.c. route, both serum and follicular fluid levels are greater compared with the i.m. route.  相似文献   
44.
OBJECTIVE: To compare the safety of recombinant human luteinizing hormone (LH) with that of urinary hCG in terms of the hemodynamic changes when they are used to induce final follicular maturation in patients undergoing in vitro fertilization (IVF). A secondary end point was efficacy in terms of IVF outcome. DESIGN: Prospective, randomized clinical trial. SETTING: University teaching hospital. PATIENT(S): Thirty IVF patients. INTERVENTION(S): Ovarian stimulation was induced with FSH under pituitary suppression. Patients were randomized to receive either hCG or recombinant human LH as a trigger of oocyte maturation (5,000 IU) and for luteal phase support (5,000 IU, 2,500 IU, and 2,500 IU on the day of follicular aspiration, 2 days later, and 5 days later, respectively). MAIN OUTCOME MEASURE(S): Mean arterial pressure, cardiac output, peripheral vascular resistance, and serum levels of progesterone, plasma concentrations of aldosterone, norepinephrine, and plasma renin activity were measured in all patients on postovulatory day 7 of the spontaneous menstrual cycle preceding IVF (baseline) and 7 days after the hCG/recombinant human LH ovulatory injection during the IVF cycle. RESULT(S): Ovarian response and IVF outcome (pregnancy rate, 60%) were similar in both treatment groups. On the seventh day after hCG/recombinant human LH administration, the peripheral vascular resistance was significantly lower and serum progesterone concentrations significantly higher in the hCG group as compared with the recombinant human LH group. The percentage change from baseline values during IVF cycles in all hemodynamic and neurohormonal variables investigated was higher (albeit not statistically different) in the group treated with hCG vs. the group treated with recombinant human LH. CONCLUSION(S): Recombinant human LH is associated with less intense circulatory changes than hCG when it is given to induce final follicular maturation and luteal phase support in IVF procedures.  相似文献   
45.
OBJECTIVE: To assess the effect of ovarian stimulation with recombinant FSH, GnRH antagonists, and hCG on endometrial maturation on the day of oocyte pick-up. DESIGN: Prospective study. SETTING: Tertiary referral center. PATIENT(S): Fifty-five women undergoing controlled ovarian hyperstimulation for IVF/intracytoplasmic sperm injection (ICSI). INTERVENTION(S): [1] Ovarian stimulation with recombinant FSH, starting on day 2 of the cycle and GnRH antagonist, starting after a median of 6 days of recombinant FSH stimulation (range, 5-12 days); [2] hCG administration for ovulation induction; and [3] aspirational biopsy of endometrium at oocyte pick-up. MAIN OUTCOME MEASURE(S): Endometrial histology at oocyte pick-up by Noyes criteria. RESULT(S): Advancement of endometrial maturation (2.5 +/- 0.1 days) as compared to the expected chronological date was observed in all antagonist cycles at oocyte retrieval. Endometrial advancement at oocyte pick-up increased in line with values of LH at initiation of stimulation and the duration of recombinant FSH treatment before the antagonist was started. CONCLUSION(S): The higher the values of LH at initiation of stimulation and the longer the duration of recombinant FSH treatment before the antagonist is started, the more advanced the endometrial maturation at oocyte pick-up.  相似文献   
46.
Cytotoxic activity of drug conjugates of human chorionic gonadotropin (hCG) and doxorubicin alone was investigated compared to doxorubicin in breast cancer cells with and without expression of hCG receptors. Expression of hCG receptor was determined in MCF-7 and MB231 breast cancer cell line using a multiplex nested rt-PCR approach. The entire sequence of mRNA encoding for hCG receptor was detected in MCF-7 but not in MB231 breast cancer cell line. Cytostatic effect of doxorubicin–hCG conjugates was investigated in these cell lines in comparison to unconjugated doxorubicin. The number of viable cells was determined after 24, 48, 72, 96, and 120 h. To exclude non-specific uptake of the carrier hCG from the culture media, a similar experiment was performed with albumin–doxorubicin conjugates. The number of viable cells decreased in a concentration depending manner after doxorubicin and hCG–doxorubicin conjugate treatment. However, the cytotoxic effect of hCG–doxorubicin conjugate was 10-fold increased compared to unconjugated doxorubin in hCG-receptor positive MCF-7 but not in hCG-receptor negative MB231 cells. Albumin–doxorubicin conjugates showed no increased toxicity compared to doxorubicin. We conclude that the cytotoxic effect of hCG–doxorubicin conjugates is mediated specifically via the hCG receptor. By using hCG conjugates, the development of more selective cytostatics can be achieved.  相似文献   
47.
We have recently introduced 125I-hCG as an elimination marker in patients with human chorionic gonadotrophin (hCG) producing testicular cancer. 125I-hCG is a well-known reagent in clinical biochemistry and is used extensively in hCG assays. Previous studies have shown that the iodination process leaves the hCG molecule mainly intact. The iodination, purification and stability of 125I-hCG tracer are described. The aim of the present study was to determine whether or not 125I is associated with hCG after the injection of 125I-hCG intravenously (i.v.) in humans. Three different methods were used. Following injection of 125I-hCG, the plasma disappearance of radioactivity and hCG were followed for a period of 28 days in 13 normal subjects. Serum from a normal healthy male following injection of 125I-hCG was analysed using a double antibody direct binding radioimmunoassay specific for holo-hCG and high performance liquid chromatography (HPLC). Following injection of 125I-hCG in eight normal healthy males and five normal healthy females, the disappearance of radioactivity and hCG showed identical paths in the 28 days follow-up period. The bindable radioactive fraction of immunologically active hCG in serum of a normal healthy male following injection of 125I-hCG was between 57.0% and 72.1%, and was constant over time. HPLC showed similar elution pattern of serum from a normal healthy male injected i.v. with 125I-hCG and 125I-hCG. Using three different methods, we were able concurrently to demonstrate the association of 125I with hCG in humans up to 28 days after injection of radiolabelled hCG i.v. Thus, information about the expected elimination of hCG can be obtained by following the elimination of activity in plasma after injection of 125I-hCG.  相似文献   
48.
本研究应用人妊娠早期新鲜绒毛组织体外分泌人绒毛膜促性腺激素 (hCG)的模型 ,探讨TH1 TH2 型细胞因子对hCG分泌的影响 ,初步阐明TH1 型 TH2 型细胞因子在人类早期妊娠中的免疫调节作用 ,为今后临床诊断及治疗提供参考依据。1 材料与方法1 .1 主要试剂 RPMI 1 640 (美国GIBCO公司 ) ,新生小牛血清 (NCS) (医科院血研 ) ,人IFNγ、人IL 4(英国 ,PEPROTECHEC有限公司 ) ,hCG放射免疫分析药盒 (天津洁瑞公司 )。1 .2 绒毛组织悬液的制备 选择经临床确诊为正常妊娠的6~ 1 2周龄的早孕妇女…  相似文献   
49.
目的探讨血清(标准物)中人绒毛膜促性腺激素(hCG)在不同的检测系统、福建省各医院的测定结果,及其与hCG相关分子变异体可能的关系。方法分别应用贝克曼Access、日本东曹(Tosh AIA-1800),在此两个免疫仪器检测系统检测不同浓度的质控物和44例患者血清的hCG;并收集福建省2007~2009年hCG质控数据、再收集文献hCG相关分子变异体检测数据进行分析。结果同一质控物、同一血清、同一hCG相关分子变异体对不同的仪器检测系统,显示不同的测定结果,有显著差异。贝克曼Access与Tosh AIA-1800线性方程为Y=1.3336X-70.199。相对而言,临床血清hCG、质控物hCG结果分别是在东曹Tosh AIA-1800(133.8%、137.2%)、雅培Abbott(132%),两仪器检测均高于贝克曼Beckmen Access(100%)。结论标准物不同的hCG分子变异体影响hCG检验结果,由于hCG分子变异体,不同的仪器产生不同的hCG检测结果。  相似文献   
50.
大鼠睾丸间质细胞分离及其鉴定   总被引:8,自引:1,他引:8  
目的和方法 :通过血管冲洗、Ⅱ型胶原酶消化以及Percoll梯度离心 ,建立大鼠睾丸间质细胞分离方法。结果 :(1)Percoll密度梯度离心后纯化的间质细胞 3β HSD染色阳性百分率可达 85 %。 (2 ) 1.2× 10 -3 IU/mlhCG可显著性增加间质细胞睾酮的分泌 (P <0 .0 5 )。结论 :提示该方法可靠且具有一定应用前景  相似文献   
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