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排序方式: 共有504条查询结果,搜索用时 15 毫秒
1.
标记抗原在贮存过程中,由于受幅射分解和脱碘影响而使免疫活性和生物活性降低。我们对自制的~(125)碘-绒毛膜促性腺激素进行了实验观察。结果显示:贮存1月后,其免疫活性和生物活性分别降低了33.1%和44.0%;经电泳纯化后的标记物的免疫活性和生物活性明显提高,分别达到了最初的90.5%和95.3%。 相似文献
2.
Summary We have identified cells which secrete human chorionic gonadotropin (HCG) of cultures if first trimester placental villi. As a first step, we identified epithelial cells using a new monoclonal antibody. We then added HCG antibodies to the cultured cells. We found that syncytiotrophoblast (and not cytotrophoblast), Hofbauer cells and some mesenchymal cells stained with HCG antibodies. 相似文献
3.
S Lipitz Z Ben-Rafael D Bider J Shalev S Mashiach 《Human reproduction (Oxford, England)》1991,6(10):1478-1479
A patient who suffered from polycystic ovarian disease and anovulation, was treated with pure follicle stimulating hormone for induction of ovulation. The treatment was stopped and human chorionic gonadotrophin was not administered because of high serum oestradiol levels and multiple follicular development. Ovulation occurred 11 days after pure follicle stimulating hormone was discontinued, the patient developed third-degree ovarian hyperstimulation syndrome and conceived with a quintuplet pregnancy. 相似文献
4.
Kolibianakis EM Schultze-Mosgau A Schroer A van Steirteghem A Devroey P Diedrich K Griesinger G 《Human reproduction (Oxford, England)》2005,20(10):2887-2892
BACKGROUND: Eliciting an endogenous LH surge by GnRH-agonist for the induction of final oocyte maturation may be more physiological compared with the administration of HCG. However, the efficacy of this intervention in patients treated for IVF with GnRH antagonists remains to be assessed. METHODS: 106 patients were randomized to receive either 10 000 IU urinary HCG or 0.2 mg Triptorelin for triggering final oocyte maturation. Ovarian stimulation for IVF was performed with a fixed dose of 200 IU recombinant FSH and GnRH antagonist was started on stimulation day 6. Luteal phase was supported with micronized vaginal progesterone and oral estradiol. The study was monitored continuously for safety and stopping rules were established. RESULTS: No significant differences were present in the number of cumulus-oocyte complexes retrieved, in the proportion of metaphase II oocytes, in fertilization rates or in the number and quality of the embryos transferred between the two groups. However, a significantly lower probability of ongoing pregnancy in the GnRH agonist arm prompted discontinuation of the trial, according to the stopping rules established (odds ratio 0.11; 95% confidence interval 0.02-0.52). CONCLUSIONS: Lower probability of ongoing pregnancy can be expected when GnRH agonist is used for triggering final oocyte maturation instead of HCG in patients undergoing ovarian stimulation for IVF with GnRH antagonists. 相似文献
5.
Olajide F.; Howell R.J.S.; Wass J.A.H.; Holly J.M.P.; Bohn H.; Grudzinskas J.G.; Chapman M.G.; Chard T. 《Human reproduction (Oxford, England)》1989,4(3):337-340
First trimester termination of pregnancy was successfully inducedin ten patients with RU 38486 followed 2 days later by a prostaglandin(Gemeprost) pessary. Human chorionic gonadotrophin (HCG) valuesremained unaltered until after the abortion. The levels of placentalprotein 12 (PP12) showed an immediate and significant fall followingRU 38486, then rose to values substantially higher than thoseat the initial visit after 2 days. These findings show thatRU 38486 has a direct inhibitory effect on tissues producingPP12 and confirm the progesterone dependency of this protein 相似文献
6.
Serum progesterone at the time of human chorionic gonadotrophin does not predict pregnancy in in-vitro fertilization and embryo transfer 总被引:2,自引:0,他引:2
Bustillo Maria; Stern J.Jaroslav; Coulam Carolyn B. 《Human reproduction (Oxford, England)》1995,10(11):2862-2867
Controversy exists as to whether the serum concentration ofprogesterone on the day of human chorionic gonadotrophin (HCG)administration following ovarian stimulation for in-vitro fertilization(IVF) and embryo transfer can be used to predict the likelihoodof success. This retrospective study was undertaken to answerthis question by analysing a large population of IVF and embryotransfer cycles (n = 756). In addition to the concentrationof progesterone on the day of HCG administration, all variablesknown to impact on IVF and embryo transfer success (such aspatient age), indication for IVF and embryo transfer, numberof oocytes retrieved and the number of embryos generated andtransferred were examined. There was a significant increasein the number of oocytes retrieved with increasing progesteroneconcentration at the time of HCG administration. However, therewas no correlation of progesterone concentration at HCG administrationwith pregnancy and implantation rates. It is concluded thatprevious reports associating a slight elevation of progesteronein gonadotrophin- releasing hormone agonist ovarian stimulationcycles for IVF and embryo transfer may be misleading becauseof a small sample size or the presence of confounding variablesthat affect IVF and embryo transfer success. 相似文献
7.
Ogueh O Jones J Mitchell H Alaghband-Zadeh J Johnson MR 《Human reproduction (Oxford, England)》1999,14(2):303-306
The aim of this study was to determine whether the current regimen of dexamethasone administration to induce fetal lung maturation affected the circulating concentrations of placental hormone. A standard regimen of dexamethasone that comprised two doses of 12-mg intramuscular injections, 12 h apart was administered to 12 pregnant women to promote fetal lung maturation in anticipation of premature delivery before 34 completed weeks of gestation. Blood samples were collected before starting the dexamethasone therapy, 24 h, and 48 h after completing therapy for the measurement of the plasma concentrations of human chorionic gonadotrophin (HCG), oestradiol and progesterone. There was a progressive fall in the plasma concentrations of HCG following dexamethasone therapy (P = 0.049 and P = 0.034, 24-h and 48-h post therapy respectively). There was an initial fall in the plasma concentrations of oestradiol after dexamethasone therapy (z = 3.059; P = 0.002, 24-h post therapy), which recovered by 48 h (P = 0.239). There was no difference between the plasma concentrations of progesterone at the three time points. The effect of dexamethasone on HCG concentrations suggests that it has a direct inhibitory effect on placental hormone synthesis or secretion. Further studies are needed to define the mechanism of action of dexamethasone on placental HCG production. 相似文献
8.
N McClure J Leya E Radwanska R Rawlins R V Haning 《Human reproduction (Oxford, England)》1992,7(6):758-764
The incidence and statistical associations of the ovarian hyperstimulation syndrome (OHSS) were studied in 304 egg retrievals with gonadotrophin-releasing hormone agonist suppression, gonadotrophin administration and follicular aspiration. In addition to preserving corpus luteum function, the luteal phase administration of human chorionic gonadotrophin (HCG) was associated with a higher incidence of severe OHSS than was supplementation with progesterone alone (12 versus 0%, P less than 0.001). Severe OHSS occurred in 3.7% and 12% of retrievals without and with pregnancy respectively (P less than 0.01). Stepwise logistic regression showed that the occurrence of moderate or severe OHSS was statistically predicted by the log of the serum oestradiol on the day the initial HCG was given (P less than 0.0001), treatment with luteal phase HCG (P less than 0.0003), and fetal number (P less than 0.0079). In the late luteal phase of cycles without luteal HCG, the serum oestradiol concentration was one-tenth and the serum progesterone concentration was one-fifth of the luteal phase value with HCG support (P less than 0.001). Without luteal phase HCG, oestradiol was two-fold higher (P less than 0.001) and progesterone was 1.4-fold higher (P less than 0.005) in pregnant than in non-pregnant women. With luteal phase HCG, oestradiol was 1.4-fold higher in pregnant than in non-pregnant women (P less than 0.05), and progesterone was 1.7-fold higher (P less than 0.001). Oestradiol upper limits of 4400 and 14,700 pmol/l (1200 and 4000 pg/ml) for cycles with and without luteal phase HCG respectively correspond to approximately 5% risk of moderate or severe OHSS with a singleton pregnancy under these conditions. 相似文献
9.
Time interval from human chorionic gonadotrophin (HCG) injection to follicular rupture 总被引:1,自引:1,他引:1
Andersen A.G.; Als-Nielsen B.; Hornnes P.J.; Andersen L.Franch 《Human reproduction (Oxford, England)》1995,10(12):3202-3205
The aim of this study was to estimate the time interval fromhuman chorionic gonadotrophin (HCG) injection to follicularrupture. Furthermore, it was observed whether there was anyeffect on the pregnancy rate if the insemination was performedat the time of follicular rupture. In a programme of intrauterineinsemination 37 consecutive cycles in 32 patients were monitoredafter stimulation with clomiphene citrate. HCG was administeredby i.m. injection when a leading follicle of at least 18 mmin diameter was observed sonographically. All patients weremonitored by sonography with 1 h intervals from 32 h after HCGinjection until the first rupture of a follicle. Inseminationwas performed immediately after the first follicular rupture.The pregnancy rate was 16% (5/32). In 66%, the largest folliclewas the first to rupture. The mean time interval from HCG administrationto first follicular rupture was 38.3 h (SEM = 0.54; range =3416). Our findings support the concept that ovulationoccurs about 38 h after HCG administration. The pregnancy ratewas within the normal range, although insemination was performedat the time of follicular rupture. The largest follicle wasnot always the first to rupture 相似文献
10.
The clinical usefulness of measuring serum concentrations ofprogesterone, human chorionic gonadotrophin (HCG) and the free-subunit of HCG in distinguishing between early viable and non-viablepregnancy, before an accurate ultrasound diagnosis is possible,was evaluated in a prospective study of patients presentingto our emergency gynaecology service with a clinical suspicionof ectopic pregnancy. Patients were selected on the basis ofinitial HCG concentrations; samples with HCG 2510 000IU/I were later analysed for progesterone and free HCG. Of the181 patients studied, 38 (21%) had an ectopic pregnancy, 108(60%) had a spontaneous abortion and 35 (19%) had a viable intra-uterinepregnancy. Concentrations of HCG and free HCG in the group withviable pregnancies were significantly higher than in the groupwith ectopic pregnancy (P < 0.001) and than those destinedto miscarry (P < 0.01). Progesterone concentrations werealso significantly higher in the viable versus the ectopic andthe spontaneous abortion groups (P < 0.001 in each case).Despite these highly significant differences there was a degreeof overlap such that it was impossible to devise a cut-off levelfor any hormone analysed, either singly or in combination, whichwould offer a clinically useful predictor of outcome. 相似文献