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The standard semen analysis frequently fails to identify subfertile males even when findings are normal and conversely often fails to identify fertile males with subnormal semen analyses. This has created the need to produce other tests of sperm physiology that will better distinguish a fertile from a subfertile specimen. Understanding more about the nature of the sperm defect should lead to the establishment of more specific and effective therapies. Until that time, it would still be reasonable to try some of the available empirical therapies even though they may work merely by a placebo mechanism.  相似文献   
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Squamous carcinoma primary in the endometrium has been rarely reported. Diagnosis of this condition requires adherence to strict histologic criteria. Most patients are postmenopausal at presentation, and long-term survival is poor. We present a patient with peritonitis and small bowel obstruction. Chemotherapy was given after disease recurrence and was ineffective. Receptor data and serum markers were obtained.  相似文献   
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PURPOSE: Interpreting the rapidly changing speech skills of young children recovering from neurological injury is difficult because developmental expectations are generally available only at relatively lengthy intervals (e.g., 6 or 12 months). In this research note, the authors describe the process of generating a Percentage of Consonants Correct-Revised (PCC-R; L. D. Shriberg, D. Austin, B. A. Lewis, J. L. McSweeny, & D. L. Wilson, 1997a) performance curve and illustrate some of its applications for assessing change in performance over time. METHOD: The authors compiled mean PCC-R scores from 16 samples of typically developing children (18-172 months) and used curve fitting to test more than 11,000 statistical models of monthly growth in PCC-R. They selected a parsimonious and developmentally plausible model with R(2) = .9839 (p < .0005) and used it to generate the PCC-R, standard deviation, and standard error expected at each monthly age. RESULTS: The PCC-R performance curve distinguished among 65 children (37-57 months of age) diagnosed independently with normal or disordered speech with a high degree of success. More important, the PCC-R performance curve can be used to identify the points at which children (18-172 months) recovering from neurological injury achieve normal-range consonant production. CONCLUSION: The curve-fitting approach holds promise as a means of interpreting temporal variations in speech production at a finer grain than existing normative data currently allow.  相似文献   
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The first four automated visual field examinations of 20 patients with clinically stable chronic open-angle glaucoma who had previously undergone manual perimetry were studied for the presence of a learning effect on mean sensitivity, number of disturbed test locations, total loss, and short-term fluctuation. A learning effect, if present, would manifest itself as an improvement in the visual field as patients become more experienced with the test. There was no apparent effect of patient experience on the mean sensitivity, total loss, or the number of disturbed test locations. There was a significant (P less than 0.0001) decrease in short-term fluctuation as measured by the root mean square between the first and second visual field examinations. These results indicate that a learning effect did not play an important role in the clinical interpretation of automated perimetry in patients with glaucoma who have previous experience with manual perimetry. In most cases, it was not necessary to obtain more than one "baseline" examination unless a patient demonstrated unusually high short-term fluctuation or had visual field defects inconsistent with the rest of the clinical examination.  相似文献   
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Malignancy may adversely influence the quality and behaviour of oocytes   总被引:1,自引:1,他引:1  
A case series of eight cycles of in-vitro fertilization (IVF) in five women diagnosed with malignant disorders is presented. These patients chose to defer definitive treatment for a chance for preservation of potential fertility. The response of these patients to ovarian stimulation, and the outcome, was compared with 17 IVF cycles in 12 age- matched patients with isolated tubal infertility. An apparent adverse influence of malignant disease on the quality and behaviour of oocytes was observed. Despite a comparable total number of oocytes per cycle in the two groups, a significantly reduced percentage of mature oocytes was retrieved per cycle from patients with malignant diseases. The oocytes from patients with malignant disorders were of a poorer quality and exhibited a significantly impaired fertilization rate compared to the controls. We propose that neoplastic processes, irrespective of the site or cell of origin, may have a detrimental impact on the biology of oocytes, an effect akin to that seen on spermatozoa in men with certain malignancies.   相似文献   
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