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51.
Background: Cardiopulmonary bypass (CPB) has been associated with activation and injury of endothelial cells, probably responsible for the systemic inflammatory response syndrome (SIRS) taking place in these patients. Methods: We measured plasma concentrations of soluble P‐selectin (sP‐s), E‐selectin (sE‐s), tetranectin (TN), vonWillebrand factor (vWF) levels, and angiotensin‐converting enzyme (ACE) activity in 31 adult patients undergoing elective coronary artery bypass grafting, just before and up to three days after surgery, and in 25 healthy volunteers. Results: Patients showed higher plasma sP‐s and sE‐s and ACE concentrations, just before surgery, but significantly lower TN levels, compared with controls. During the first three postoperative days (PD), the concentration of each of the molecules followed a different and independent pattern, although in the third PD, the levels of sP‐s, sE‐s and ACE were higher and those of vWF and TN lower, compared with the preoperative ones. However, patients had higher sP‐s (P=0.06), sE‐s (P=0.07), and vWF (P=0.005), but lower TN concentrations (P=0.02) on the third PD compared with controls. Conclusions: CPB is characterised by pronounced changes in plasma sP‐s, sE‐s, TN, vWF levels, and ACE activity, which are associated with significant alteration in the intra‐ and early postoperative endothelial function observed in open heart surgery. J. Clin. Lab. Anal. 24:389–398, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
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This pilot study evaluated the possibility of preventing early ovarian hyperstimulation syndrome (OHSS) by increasing the daily dose of gonadotrophin-releasing hormone (GnRH) antagonist administration (to twice a day) in oocyte-donor cycles stimulated with the antagonist protocol. The study included 72 oocyte donors who underwent ovarian stimulation using the GnRH antagonist protocol and might have had their cycle cancelled because of ovarian hyper-response. All women were donors presenting a rapid rise of oestradiol ?3000 pg/ml early in the stimulation period with more than 15 follicles of ?15 mm in diameter. By decreasing the rFSH dose to 75 IU a day with an additional daily dose of GnRH antagonist (0.25 mg twice a day), the oestradiol concentrations were lowered or reached a plateau before human chorionic gonadotrophin was given. A marked decrease in oestradiol concentrations and ovarian volume was observed on the day of oocyte retrieval and 3 days post retrieval. None of the donors needed coasting, were cancelled or developed OHSS. In over-responding oocyte donors, by increasing the usual GnRH-antagonist dose to twice a day during ovarian stimulation, the oestradiol rise can be blocked while a minimal follicular stimulation may continue without the risk of developing OHSS or affecting the outcome.This study was conducted in order to investigate whether GnRH antagonist (Ganirelix) may prevent the early OHSS by doubling the daily dose in oocyte donor cycles stimulated with the antagonist protocol. Seventy two oocyte donors at high risk for OHSS were included in the study that might have their cycle cancelled because of ovarian hyperesponse. All cases were donors presenting significantly elevated or rapidly rising serum estradiol levels E2 ? 3000 pg/ml with more than 15 follicles none of which had the appropriate diameter to be considered mature for triggering ovulation. By decreasing the rFSH dose to 75IU a day with an additional daily dose of GnRH antagonist (0.25 twice a day) the estradiol levels were lowered or reached a plateau before the hCG was given. A marked decrease of estradiol levels and ovarian volume was observed the day of oocyte retrieval and three days post retrieval. None of the donors needed coasting, were cancelled or developed OHSS.In conclusion, in oocyte donors at high risk for OHSS, by increasing to twice a day the usual GnRH-antagonist dose one or two days before hCG administration, the estradiol rise could be blocked while a minimal follicular stimulation may continue without the risk of developing OHSS or affecting the outcome.  相似文献   
54.

Objective

To evaluate whether intrauterine injection of embryo culture supernatant before embryo transfer has any impact on pregnancy and implantation rates.

Study design

A total of 400 cycles, of which 200 IVF/ICSI and 200 oocyte donor (OD), were randomly assigned to have their uterine cavity injected (group I) or not (group II). Primary endpoints to be studied were pregnancy and implantation rates.

Results

Clinical pregnancy rate per transfer (47.87%, 90/188 versus 48.45%, 94/194) based on transvaginal scan findings at 7 weeks of gestation and implantation rate (25.6% versus 26.5%) were similar in the two groups. The day of embryo transfer, day 3 or day 5, did not affect the final outcome.

Conclusion

Injection of embryo culture supernatant into the uterine cavity, 30 min before the embryo transfer on either day 3 or 5, neither improves nor adversely affects the pregnancy rate in IVF/ICSI or oocyte donation cycles.  相似文献   
55.
Due to the known adverse effect of endometriosis on gamete quality, it has always been difficult to demonstrate a direct effect of endometriosis on implantation. In order to eliminate these confounding effects, this prospective comparative study studied a population of menopausal recipients with and without endometriosis sharing sibling oocytes coming from the same donor. The aim was to understand the impact of endometriosis on implantation, pregnancy and live birth rates in menopausal recipients. A total of 240 menopausal recipients of donated sibling oocytes, were divided in two groups. Group I consisted of 120 recipients diagnosed with endometriosis and group II consisted of 120 controls. The implantation and pregnancy rates were significantly lower in the endometriosis group compared with the control group (23.81% versus 31.48%, P = 0.019; 45.00% versus 58.33%, P = 0.039, respectively). In oocyte donation cycles, a recipient‘s history of endometriosis might have a negative impact on implantation, pregnancy and live birth rates, even in menopausal women.Infertility in endometriosis may be due to poor oocyte quality or embryos with decreased ability to implant due to impaired fertilization. There are no conclusive data on the impact of endometriosis on implantation. The already-known adverse effect of endometriosis on gamete quality makes it more difficult to demonstrate a direct effect of endometriosis on implantation. In order to eliminate these confounding effects we studied a population of menopausal recipients with and without endometriosis sharing sibling oocytes coming from the same oocyte donor. The oocyte donation model was used in an attempt to understand whether the endometrium, the oocytes or both are affected by endometriosis. The aim of the present study was to understand the impact of endometriosis on implantation, pregnancy and live birth rates in menopausal recipients. A total of 240 menopausal recipients of donated sibling oocytes were divided into two groups. Group I consisted of 120 recipients diagnosed with endometriosis and group II consisted of 120 controls. The pregnancy and implantation rates were significantly lower in the endometriosis group compared to the control group (45.00% versus 58.33%, P = 0.039) and (23.81% versus 31.48%, P = 0.019) respectively. In oocyte donation cycles, a recipient’s history of endometriosis might have a negative impact on implantation, pregnancy and live birth rates, even in menopausal women.  相似文献   
56.
OBJECTIVES: To investigate embryonic heart rate (EHR) and yolk sac diameter (YSD) during the first trimester and their role as prognostic markers of first trimester pregnancy outcome. STUDY DESIGN: Prospective cohort study involving 219 women conducted in the 4th Academic Department of Obstetrics and Gynaecology, Aristotle University of Thessaloniki, Greece. Gestational age (GA) was determined ultrasonographically based on gestational sac diameter and crown-rump length. EHR and YSD were evaluated during the first 12 weeks and subsequently compared between the pregnancies that continued beyond the first trimester and those that resulted in spontaneous abortion. Receiver-operating characteristic (ROC) curves were used for the evaluation of the prognostic value of the combination of gestational age with embryonic heart rate and yolk sac diameter. RESULTS: The EHR and YSD were significantly correlated to advancing gestational age (p<0.001) in pregnancies continuing beyond 12 weeks. Pregnancies that resulted in spontaneous abortion exhibited a statistically significant lower EHR (p<0.001), smaller YSD (p=0.001) or absent yolk sac. ROC curve analysis demonstrated the predictive value of the combination of GA with EHR (area under the ROC curve: 0.971, p<0.001) and GA with YSD (area under the ROC curve: 0.858, p<0.001) for first trimester pregnancy outcome. CONCLUSIONS: EHR and YSD progressively increase in healthy pregnancies during the first trimester. Embryonic bradycardia and absence of yolk sac or even a smaller yolk sac diameter than expected for any gestational age are predictors of poor pregnancy outcome during the first 12 weeks.  相似文献   
57.
Use of a non-contact infrared laser (IRL) or acid Tyrode's for zona drilling before embryo biopsy was compared by assessing blastomere viability using various fluorescent markers or culture of the single biopsied blastomere, and, by cytoskeletal and molecular cytogenetic analysis of the biopsied embryos following culture to the blastocyst stage. There was no significant difference in the proportion of biopsied embryos that showed no damage in both the biopsied blastomere and in the remaining embryo (acid Tyrode's: 75% versus IRL: 68%), or in the proportion of single biopsied blastomeres that divided in culture (P > 0.05). However, single biopsied blastomeres from laser drilled embryos showed a greater tendency to form miniblastocysts. The proportion of laser or acid Tyrode's biopsied embryos that reached the blastocyst stage by day 6 was similar, although evident earlier (day 5) in the laser biopsied embryos. Spindle abnormalities at the blastocyst stage included tripolar and tetrapolar spindles, but their incidence was not significantly different from controls. In addition, no significant difference was observed in the incidence of chromosomal abnormalities and mosaicism between the two groups. It is concluded that using an IRL at a safe working distance does not cause adverse immediate or longer term effects on the development of human biopsied embryos, although damage can occur if drilling within this distance is unavoidable. Acid Tyrode's drilling can also cause damage, and tended to retard blastocyst development.  相似文献   
58.
OBJECTIVES: To evaluate the application of Doppler imaging in the differential diagnosis of placental masses and perinatal outcome. METHODS: A retrospective study of all cases referred for suspicion of placental chorioangioma over a nine and a half year period. Only cases in which color flow mapping and pulsed Doppler examination were performed were considered. RESULTS: Fourteen cases fulfilled the criteria and included seven cases of chorioangioma, two cases of placental hemorrhage and five cases of a placental mass which resolved during pregnancy. All cases of chorioangioma could be distinguished by increased blood flow within the mass. Polyhydramnios was associated with six cases of chorioangioma. Rapid tumor growth, premature labor and neonatal death occurred in one case. Premature labor occurred in six cases of chorioangioma and both cases of placental hemorrhage. IUGR was associated with two cases of chorioangioma and both cases of placental hemorrhage. All cases of resolving placental mass delivered uneventfully at term. CONCLUSIONS: Color Doppler is a useful tool in the differentiation of placental masses. Such masses should be followed up regularly because their growth rate is variable and unpredictable.  相似文献   
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60.
In conventional IVF cycles with total fertilization failure, rescue intracytoplasmic sperm injection (ICSI) performed 24h after insemination has yielded poor results. However, when ICSI is used, total fertilization failure is a rare event. The aim of the present study is to investigate the degree of sperm contribution to fertilization failures using the egg-sharing model in oocyte donor cycles. The study included only the oocyte donor cycles of sibling oocytes with total fertilization failure in at least one of the matched recipients. Oocytes from 49 oocyte donor cycles were equally shared among 98 recipients undergoing conventional IVF. Due to total fertilization failure in half of the recipients, rescue ICSI was carried out. Compared with the conventional IVF only group, the rescue ICSI group had a lower pregnancy rate (30.61% versus 71.43%), clinical pregnancy rate (28.57% versus 67.35%) and ongoing pregnancy rate (28.57% versus 63.27%) (all P<0.01). Cryptic sperm defects in apparently normal spermatozoa may be the cause of total fertilization failure, indicating the need for simple routine tests to detect them.  相似文献   
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