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S Oehninger L Veeck D Franken T F Kruger A A Acosta G D Hodgen 《Fertility and sterility》1991,55(6):1165-1170
OBJECTIVE: The purpose of this study was to investigate the sperm-binding potential of human oocytes at different stages of nuclear maturation under hemizona assay (HZA) conditions. DESIGN: This was a prospective study designed in a blinded fashion. SETTING: Academic research environment approved by the Institutional Review Board. PATIENTS: Surplus oocytes, donated by patients undergoing in vitro fertilization therapy after gonadotropin stimulation, were analyzed. Semen from a fertile donor was used in all assays. INTERVENTIONS: Five groups of oocytes were considered: (1) immature, prophase I; (2) metaphase I; (3) metaphase II; (4) inseminated, unfertilized metaphase II; and (5) immature, prophase I oocytes matured in vitro to metaphase II. Oocytes were stored in salt solution (pH 7.2) and microbisected before assay. MAIN OUTCOME MEASURE(s): Tight binding of sperm to the zona pellucida under HZA conditions was evaluated after 4 hours of gametes coincubation. RESULTS: Metaphase II oocytes (groups 3 and 4) had significantly higher binding than other groups (P = 0.0001). The mean value of the difference between the two halves (hemizona) was not significant, thus showing a small intra-assay variation for all maturational stages. CONCLUSIONS: Full meiotic competence of human oocytes is associated with an increased zona pellucida-binding potential. 相似文献
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Ralf Henkel Susan Cooper Khalied Kaskar Wolf-Bernhard Schill Ursula-F. Habenicht Daniel R. Franken 《Journal of assisted reproduction and genetics》1995,12(9):644-649
Purpose
A total of 86 fresh and salt-stored immature human oocytes derived from postmortem ovarian tissue were used for this study.Methods
Oocytes were randomly incubated either in synthetic human tubal fluid medium (untreated zonae) or in a chemically defined medium (treated zonae).Results
Sperm binding experiments using hemizona assay conditions exhibited a 10-fold increased binding of sperm to treated compared to untreated oocytes (272.7±43 versus 24.3±15 sperm bound, respectively; P<0.0001). pH recordings during incubation showed elevated pH levels of 8.1 compared to pH 7.2 among treated and untreated zonae, respectively. Ultrastructural examination showed a spongy appearance of the surface of treated zonae, whereas untreated zonae appeared compact with smooth surface.Conclusions
The marked increase in sperm binding among treated zonae, together with the ultrastructural findings, suggest that the altered zona surface enhances sperm binding. The physiological maturational process of the zona pellucida might be manipulated in vitro, thus increasing sperm binding to the zona.Presented at the IXth World Congress on In Vitro Fertilization and Alternate Assisted Reproduction, April 3–7, 1995. Vienna, Austria. 相似文献
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Berbaum KS; el-Khoury GY; Franken EA Jr; Kathol M; Montgomery WJ; Hesson W 《Radiology》1988,168(2):507-511
The effect of knowledge of localizing symptoms and signs in the detection of fractures was studied. Forty radiographs of the extremities were examined twice by seven radiologists; the sessions were separated by 4 months. In 26 cases, a subtle fracture was present; 14 cases were normal. In half of the cases at each session, the precise location of pain, tenderness, or swelling was provided. The observer was asked to determine if the case was normal or abnormal (provide the exact location of the fracture) and to indicate the degree of confidence in the diagnosis. Responses were converted to a numeric scale for analysis. Analysis of receiver operator characteristic parameters indicates that clues regarding location of trauma facilitate detection of fractures. The improvement is based largely on an increased true-positive rate without an increased false-positive rate, regardless of the decision criteria of the radiologist (overall willingness to "overread" or "underread"). This has direct clinical applicability and reinforces the plea of radiologists for precise clinical information. 相似文献
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The authors reexamined a suspected difference in the effects of clinical information upon detection of nodules vs. more diverse lesions by directly incorporating classification specificity into detection ROC analysis. Categorical prompts, correct for specific abnormalities, led to detection superior to unprompted reading when non-nodule trials (various lesion types) were analyzed. Trials that contained pulmonary nodules, or contained no lesions but had been preceded by "possible tuberculosis" or "rule out metastatic disease" prompts, failed to demonstrate the diagnostic prompt superiority. Perceptual responses may differ when nodules are compared with more complex lesions. 相似文献
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Cholecystokinin-decreased food intake in rhesus monkeys 总被引:1,自引:0,他引:1
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This study analyses the influence of female and male patient age and human
menopausal gonadotrophin (HMG) requirements on clinical pregnancy rates and
live birth rates with ovulation stimulation using HMG in combination with
intrauterine insemination (IUI). In this study, 363 consecutive HMG/IUI
treatment cycles in 184 patients carried out at a university fertility
centre were analysed in a retrospective fashion. The main outcomes measured
were clinical pregnancy rates and live birth rates. Increased female
partner age (> or = 35) and male partner age (> or = 40) were found
to negatively influence pregnancy rates with HMG/ IUI therapy. In addition,
this study demonstrated a critical threshold of HMG requirements beyond
which pregnancy did not occur. No pregnancies occurred in treatment cycles
requiring > 25 ampoules (1875 IU) of menotrophins to achieve follicular
maturity, irrespective of patient age. In conclusion, female partner age,
male partner age, and HMG requirements all significantly influence
pregnancy rates with HMG/IUI therapy.
相似文献