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941.
942.
Our aim was to identify independent factors that correlated with colposcopically directed biopsy's reliability as a method for diagnosing early cervical cancer. One hundred ninety-one of a total of 2265 patients who had colposcopic examinations because of abnormal Papanicolaou smears were included in this study. These patients had all undergone a hysterectomy after being diagnosed as having cervical intraepithelial neoplasia grade III by colposcopically directed biopsy. By univariate analysis, old age (P = 0.0195), achievement of menopausal status (P = 0.0046), large lesion size (P = 0.0021), and unsatisfactory colposcopy (P = 0.0017) were found to be associated with the nondiagnosis of early cervical cancer. However, multivariate analysis using stepwise logistic regression revealed that large lesion size (P = 0.003) and unsatisfactory colposcopy (P = 0.0008) were the only independent factors that correlated with nondiagnosis. Our findings indicate that in order to reach a clear-cut diagnosis, cases with either unsatisfactory colposcopy or satisfactory colposcopy with large lesions (despite a lack of histologic evidence of invasions) should undergo a diagnostic conization.  相似文献   
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945.
A prospective, cohort study of 75 consecutive patients requiring management in the medical intensive care unit (MICU) of the Singapore General Hospital was carried out over a five-month period to determine thyroid and adrenocortical profiles and evaluate their use in predicting patient outcome. Up to 88% of patients had at least one abnormal thyroid function and 77% had abnormal adrenocortical function test results. There were significantly lower triiodothyronine, thyroxine and free thyroxine, but not thyrotropin levels, and higher cortisol levels in non-survivors compared to survivors (all P < 0.01). Of the endocrine parameters, triiodothyronine and cortisol concentrations were independent predictors of outcome. The overall predictive accuracy of combining these two variables on admission into the MICU was 74%. The APACHE II (acute physiology and chronic health evaluation II) score alone predicted outcome with 71% accuracy, and in combination with triiodothyronine and cortisol levels improved accuracy to 84%. The use of dopamine alone predicted outcome with 74% accuracy, and in combination with triiodothyronine and cortisol levels, improved accuracy to 84%. Measurements of total triiodothyronine and cortisol concentrations on admission to the MICU, and consideration of the use of dopamine improve on the APACHE II score in outcome prediction.  相似文献   
946.
An investigation was conducted to assess the prevalence of Akabane virus antibodies in domestic ruminants from different ecological zones of Sudan. Neutralizing antibodies were demonstrated in sheep, goats and cattle sampled between 1979 and 1980 from El Obeid, Nyala, Kassala, Jonglei and Sennar. The highest prevalence was in Jonglei where 27% of six sheep, 36% of eleven goats and 47% of 90 cattle had antibodies to the virus. Although antibodies were demonstrated in 8% of 79 dams and 15% of 70 dams of two sentinel calf herds in Central Sudan at Shambat and Um Benein, respectively, none of their sentinel calves sampled between 1981 and 1983 had antibodies. Antibodies were subsequently detected in 8 (14%) out of 57 calves from Shambat and 5 (12%) out 40 from Um Benein of the random samples collected during 1985 from 1-3 year old calves. The implications of these results are discussed.  相似文献   
947.
Radioiodinated N-benzyloxycarbonyl-tyrosyl-alanyl diazomethane (Z-Tyr[125I]-AlaCHN2) was previously shown to selectively label two (28 and 31 kDa) Leishmania mexicana cysteine proteinases common to both the promastigote and the amastigote stages. Here we have confirmed the specificity of the compound towards two similar enzymes of axenic L. mexicana amastigotes and demonstrated that lesion amastigotes, axenic amastigotes and stationary promastigotes internalized the 125I-labeled inhibitor at different rates. Uptake of Z-Tyr[125I]-AlaCHN2 by the parasites, which was not significantly modified by changing the medium pH, was clearly correlated with the binding of the compound to the 28- and 31-kDa cysteine proteinases, as judged by the specificity of enzyme labeling in gelatin gels and the recovery of 75% or more parasite-associated radioactivity in TCA-insoluble fractions. For all three developmental stages, uptake markedly increased with time and linearly up to 60 min, but throughout the period examined, radiolabel accumulation occurred more efficiently in amastigotes. By 5 h, when values were near or at saturation, radioactivity (in cpm/microgram of total protein) associated with lesion amastigotes was 1.8- and 2.9-times that recovered from axenic amastigotes and stationary promastigotes, respectively. Pulse-chase experiments, in which cysteine proteinases were fully blocked with Z-Phe-AlaCHN2 prior to the pulse with Z-Tyr[125I]-AlaCHN2, showed that labeling of the amastigote enzymes could be partially restored, whereas labeling of promastigote proteinases could not, after a 5-h chase period in inhibitor-free medium.  相似文献   
948.
949.
This article describes the objectives and content of a workshop held in Managua, Nicaragua, during November 1995, on screening for cervical cancer. The aims were to discuss cost-effective models of screening in countries with a high incidence of cervical cancer and to reach a consensus on principles for screening that is balanced with a country's resources. The workshop aimed to develop a planning framework and to identify program strengths and weaknesses by country. In 1990 there were 25,000 deaths due to cervical cancer in Central America; even so, most countries attach a low priority to cervical cancer screening. Workshop plenary sessions were devoted to discussions about the natural history of cancer of the cervix and the implications for screening, the high costs of human papillomavirus (HPV) tests, approaches to national registries of cervical cancer, screening issues in Central America, downstaging, laboratory quality control issues, treatment of abnormalities, recruitment of women, and IEC. This report includes individual country program reports for Nicaragua, Panama, Haiti, the Dominican Republic, Guatemala, Honduras, and St. Vincent and the Grenadines. Participants concluded that priority should be placed on education about cancer and cancer of the cervix and education of primary health care professionals. It was agreed that all participating countries should begin pilot programs adapted to resource availability, with the idea of a later nationwide expansion. Health care professionals who treat women during the prime reproductive years should use the opportunity to identify women at high risk of invasive cancer. There is overcoverage of women aged under 35 years and insufficient coverage of women aged 35-64 years. Health programs need to enlist the help of women's groups in creating a need and demand in communities. Cytology laboratories need to provide quality services.  相似文献   
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