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N. V. Bashmakova G. N. Chistiakova I. A. Gazieva Y. M. Trapeznikova D. O. Mazurov 《Gynecological endocrinology》2015,31(10):31-33
AbstractThis study was undertaken to compare the concentrations of pro- and anti-angiogenic growth factors, nitric oxide (NO) stable metabolites in maternal serum and embryonic left ventricular (LV) isovolumic relaxation time (IRT, ms) during the first trimester in two groups of women: with pregnancy conceived by assisted reproductive technologies (ART, n?=?39) and normally conceived (control group, n?=?68) pregnancy. The concentration of vasoconstrictor endothelin 1 was 45.5 times more in ART than in control group. On the contrary, the concentrations of NO stable metabolites in ART were 1.9 times less than in control women. The assessment of angiogenic suppressors in ART women demonstrates the decrease in s-endoglin concentration was 1.6 times and in soluble receptor to vascular endothelial growth factor concentration was 2.0 times in comparison with control group. There was a significant increase in LV IRT in ART embryos in comparison to control ones. These data suggest significant changes in pro- anti-angiogenic factors balance and increase in vascular impedance in ART-conceived embryos. 相似文献
3.
目的:探讨宫腔镜检查术在辅助生殖技术中应用的重要性。方法:对150例拟行辅助生殖技术的不育妇女行常规宫腔镜检查。结果:宫腔镜150例中47例(31%)有镜下异常,其中:子宫内膜息肉或息肉样增生18例(12%),子宫内膜单纯性增生17例(11%),子宫畸形7例(5%),宫腔粘连狭窄3例(2%),子宫内膜结核1例(0.7%),子宫黏膜下肌瘤或腺肌瘤1例(0.7%)。以宫腔镜诊断为标准,阴道超声诊断敏感性、特异性、阳性预测值、阴性预测值、准确率分别为66%(31/47)、98%(101/103)、94%(31/33)、86%(101/117)、88%(132/150),子宫造影分别为26%(12/47)、100%(95/95)、100%(12/12)、73%(95/130)、75%(107/142)。结论:宫腔镜检查术具有良好的可接受性和准确性,应作为辅助生殖技术前的常规检查。 相似文献
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Ming-I. Hsu Paul Kolm John Leete Ke Wen Dong Suheil Muasher Sergio Oehninger 《Journal of assisted reproduction and genetics》1998,15(8):496-503
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
6.
T K Al-Hussaini D M Abd el-Aal I B Van den Veyver 《International journal of gynaecology and obstetrics》2003,83(2):179-186
OBJECTIVES: To present a series of women with recurrent molar pregnancies, including rare familial cases, and discuss etiology and treatment options. METHODS: We performed a detailed clinical evaluation and pedigree analysis of five Egyptian women with recurrent pregnancy loss due to molar pregnancy. RESULTS: The women had a history of four to nine consecutive hydatidiform moles but of no viable pregnancies. Two of the women had molar pregnancies with different husbands who themselves had viable offspring from previous wives; and three of them, who belonged to a family with extensive intermarriage, had a pedigree consistent with an autosomal recessive maternal-effect mutation. CONCLUSIONS: Recurrent pregnancy loss due to habitual molar pregnancy is uncommon and familial cases are extremely rare. The etiology of this disorder is not well understood but likely results from a maternal-effect mutation. Management options are limited, especially for couples who desire to have their own genetic offspring. 相似文献
7.
KEIJU KOTOH KOJI ISHII YOSHINOBU ABE PHILLIP DELEUZE DANIEL LOISANCE 《Artificial organs》1994,18(12):918-922
Abstract: Right ventricular (RV) failure during the use of a left ventricular assist device (LVAD) is the leading cause of death in circulatory support patients. Previous work, both experimentally and clinically, has shown the difficulties in predicting the behavior of the right ventricle at the start of LVAD. An experimental study has been designed to evaluate RV functional changes during LVAD and its relation to preload changes. The model used adult mongrel pigs (n = 10). Right ventricular functional parameters were measured with a thermodilution RV ejection fraction catheter. The left ventricle was supported by a Nippon Zeon blood pump. Two groups were studied, the first one was the LVAD–off group (n = 5) and the other was the LVAD–on group (n = 5) which was supported by LVAD at maximum flow. Change of cardiac output, mean pulmonary artery pressure (PAP), RV stroke work, and RV ejection fraction in both groups were not significantly different. However, the relationship between right ventricular end–diastolic pressure (RV–EDP) and right ventricular stroke volume (RVSV) was significantly changed at a high level of RV–EDP. When RV–EDP was over 6. 5 mm Hg in the LVAD–off group, RVSV decreased to 52. 3 ± 11. 5 ml while in the LVAD–on group, RVSV increased to 97. 2 ± 22. 0 ml. The change in PAP in the LVAD–on group was lower than in the LVAD–off group. We conclude that, at the volume overload state, LVAD can reduce the afterload of the right ventricle and maintain Frank–Starling's effect, thus having a beneficial effect on right ventricular performance. 相似文献
8.
《Journal of the American Medical Directors Association》2022,23(2):280-287
ObjectivesDevelop and evaluate the implementation of a proposed model for large-scale data-driven quality improvement in assisted living.DesignWe conducted a mixed-methods evaluation of the implementation of a large-scale data-driven quality improvement collaborative of Wisconsin assisted living communities (ALCs).Setting and ParticipantsThe model has been voluntarily implemented by 810 Wisconsin-licensed ALCs serving >20,000 residents.MethodsThe model was codesigned iteratively 2009-2012 by a public-private multistakeholder advisory group. Using system usage statistics and project records, we evaluated implementation outcomes: appropriateness, acceptability, adoption, feasibility, fidelity, penetration, and sustainability.ResultsImplementation for ≥1 quarter was feasible for 92% of the 810 ALCs that enrolled. The model has been deemed appropriate and acceptable by public-private stakeholders representing residents, providers, regulators, and payers, and appropriateness for ALCs serving different populations has been iteratively improved through targeted workgroups. The model is currently adopted in Wisconsin by 31% of the 1573 ALCs in provider associations. Among adopters, 88% on average implemented the model with fidelity to key membership rules per quarter. The model achieved demographic and institutional penetration by currently reaching 24% of Wisconsin ALC residents and by leveraging initial grant funding to become integrated in Wisconsin's annual Medicaid budget and being central to Wisconsin's incentive program to managed care organizations. Model implementation for 8 years has been sustained by member enrollment for nearly 4 years on average, with 71% of members enrolled >2 years and sustained early adopters representing 37% that have been enrolled >5 years.Conclusions and ImplicationsThis is the first implementation study of large-scale data-driven quality improvement in assisted living, despite its demonstrated value in other health care sectors. The article proposes a model with core components and implementation strategies drawing on a decade-long public-private collaboration. The implementation study findings establish a promising path and future directions for wider implementation. 相似文献
9.
Since its establishment many researchers have been trying to automate the process of extracorporeal circulation (ECC). We developed a preliminary experimental model of an automatic regulatory system for ECC. The purpose of the system was to regulate basic hemodynamic parameters such as pump flow and withdrawal blood volume. It was divided into three main components: data sampling unit, central processing unit, and controlling unit. Based on this model we were able to achieve autoregulation of ECC using minimum configuration; however, the system lacked smoothness. This was partly because it was based on a "static" regulation system which used conditional statements having multiple parameters. In this study, we applied fuzzy logic to the former model to achieve more accurate and reliable regulation. We report experimental results for the new system and compare the data between clinical circulation in 13 infants (mean body weight, 13.32 +/- 5.99 kg) and experimental regulation in 7 mongrel dogs (mean body weight, 11.9 +/- 2.53 kg). The comparative study revealed no statistical difference between the two groups. This result suggests that the automatic regulation of ECC may be an alternative to manual operation by a professional perfusionist in the near future. 相似文献
10.
Edward C. Ditkoff Jennifer Plumb Amy Selick Mark V. Sauer 《Journal of assisted reproduction and genetics》1997,14(3):145-147
Purpose: Our purpose was to characterize and describe anesthesia practice in programs performing IVF in the United States.
Methods: We used a telephone survey requiring respondents to be either the program director, a physician, or a nurse familiar with
the practice. Two hundred seven (78%) Society of Assisted Reproductive Technology (SART) registered programs agreed to participate.
Programs were divided by geographic region and type of practice (academic versus private).
Results: Ninety-one private (68%) and 41 academic (56%) programs used personnel provided by the Department of Anesthesiology. Conscious
sedation was performed most commonly (95%). The remaining 5% used primarily either general, regional, or local anesthesia.
Typical recovery times were 90 to 120 min. Average costs of anesthetic administration were $300–$400 and were similar among
groups except for the Eastern academic programs, with a higher mean cost of $543. Programs using personnel from anesthesiology
reported higher costs compared to programs utilizing their own staff ($391±15 vs $157±11; P<0.05). Complications were infrequent
(<10%); no hospitalizations or serious life-threatening incidents were reported.
Conclusions: A large number of programs safely used their own trained personnel to deliver anesthesia, and realized a significant reduction
in cost. 相似文献