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81.
Background: Clearance of large molecules from the interstitialspace is an important function of lymphatics andis affected by local pathologic changes.Objective: To determine if the clearance rate ofinterstitially injected albumin is correlated to tumour characteristicsand outcome in women with invasive breast cancer.Method: In a consecutive series of women comingto biopsy for suspected breast cancer, technetium-tagged albuminwas injected into the tissue adjacent to thepalpable mass. The isotope disappearance rate was measuredover two hours. Also assessed were the maximumvessel density (MVD – using Factor VIII polyclonalantisera), the proliferation rate (using Ki-67 antisera), nodestatus, tumour size, histologic and nuclear grade, mitoticrate, and p53 and c-erbB-2 oncoproteins. All patientswere followed until relapse and for a minimumof 10 years.Results: In multivariate analysis, an association between relapse-freesurvival and isotope clearance rate was suggested (p= 0.024). The best outcome was seen inpatients with the least isotope clearance. Node status,size, histologic and nuclear grade, and mitotic ratecorrelated with survival. MVD did not correlate withsurvival and was inversely related to the isotopeclearance rate. Tumour proliferation rate, and the c-erbB-2and p53 oncoproteins did not relate to outcome.Conclusion: The role of lymphatics in breast canceris difficult to study. Measurement of interstitial clearancemay be a useful technique and could bea prognostic factor.  相似文献   
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We reviewed the clinical, sonographic and pathologic findings in eight neonates in whom diffuse enlargement and abnormal echogenicity of the adrenal glands was documented sonographically. Four of the patients suffered from perinatal asphyxia and two others required mechanical ventilation for other reasons. Six patients died and one suffers from severe development delay, cerebral palsy and failure to thrive. Sonographically, the glands were enlarged, their surface was smooth and there was loss of the central echogenic stripe. Diffuse sinusoidal congestion was found histologically in all five in whom autopsies were performed. These sonographic findings represent part of the spectrum of adrenal changes in neonatal asphyxia and other causes of perinatal stress, and may be associated with poor outcome because of other sequelae of asphyxia. Received: 12 March 1998 Accepted: 8 June 1998  相似文献   
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OBJECTIVE: To study maternal and neonatal effects of combination nucleoside analog therapy administered to human immunodeficiency virus (HIV)-infected pregnant women for maternal indications. METHODS: A multicenter, prospective observational study was undertaken at six perinatal centers in the United States and Canada that supported regional referral programs for the treatment of HIV-infected pregnant women. Demographic, laboratory, and pregnancy outcome data were collected for 39 women whose antiretroviral treatment regimens were expanded to include more than one nucleoside analog for maternal indications. The 40 newborns were monitored at pediatric referral centers through at least three months of age to ascertain their HIV infection status. RESULTS: For all 39 women, zidovudine (ZDV) therapy was instituted at 13.4 +/- 8.2 weeks, with a second agent (lamivudine [3TC] in 85% of cases) being added at a mean gestational age of 17.6 weeks. Duration of therapy with two agents was 20.6 +/- 10.4 weeks overall, with no women stopping medications because of side effects or toxicity. No significant changes in maternal laboratory values were seen, except for an increase in mean corpuscular volume, over the course of pregnancy. No clinically significant adverse neonatal outcomes were noted, with all but the three preterm newborns leaving hospital with their mothers. Neonatal anemia (hematocrit < 50%) was seen in 62% of newborns, with no children needing transfusion; mild elevations of liver function tests, primarily aspartate aminotransferase, were noted in 58% of newborns tested, though none were clinically jaundiced. Overall rate of neonatal HIV infection was 2.5% (95% confidence interval: 0.1-13.2%). CONCLUSION: Combination antiretroviral therapy during pregnancy with two nucleoside analogs was well-tolerated by mothers and newborns, with no significant short-term toxicities or side effects noted. Surveillance of exposed newborns' hematologic and liver function appears warranted.  相似文献   
84.
OBJECTIVE: To determine the extent of clinical knowledge of HIV/AIDS that physicians in Barbados have and their attitudes towards persons living with HIV/AIDS. METHODS: In 2000 the Barbados Association of Medical Practitioners conducted a survey in order to assess its members' views on HIV/AIDS issues. Over a two-month period 203 physicians (76% of all those practicing in the country) were interviewed. The survey included physicians working in private practice and the public sector. They were surveyed individually concerning their attitudes towards counseling as well as their clinical knowledge, perception of safe practices, fear of occupational exposure, views on ethical issues, experience treating HIV/AIDS patients, and background with HIV/AIDS continuing education. RESULTS: In comparison to physicians who had graduated in later years, physicians who had graduated in 1984 or earlier had seen fewer HIV/AIDS clients, had lower levels of knowledge about the disease, were more likely to test for HIV/AIDS without informed consent, and were less likely to have ever attended a continuing education training course on HIV/AIDS. Overall, knowledge of the clinical indications of HIV/AIDS was low, and 76% of the physicians did not think they had adequate counseling skills. Over 80% of the physicians were comfortable looking after HIV/AIDS patients. While 95% of the physicians would not release HIV test results without a patient's consent, 33% would test, without consent, a seriously ill patient, and 15% would test without consent a patient upon whom they had to perform an invasive procedure if they perceived the patient to be from a high-risk population such as gay men or commercial sex workers. Only 53% of the physicians had attended an HIV/AIDS in-service training program between 1995 and 1999. CONCLUSIONS: Physician training in Barbados should focus on all aspects of HIV/AIDS care, including clinical and emotional factors. Attendance at such training should be mandatory for public sector physicians, and medical school curricula need to be examined to ensure their HIV/AIDS content is current and comprehensive.  相似文献   
85.
Colorectal cancer prevention.   总被引:10,自引:0,他引:10  
Colorectal cancer is the second leading cause of mortality in the United States. In the United States, the cumulative lifetime risk of developing colorectal cancer for both men and women is 6%. Despite advances in the management of this disease, the 5-year survival rate in the United States in only 62%. Because only 38% of patients are diagnosed when the cancers are localized to the bowel wall, it is likely that widespread implementation of screening could significantly improve the outcome. Colorectal cancer screening is cost effective, irrespective of the methods used. In addition to currently available methods (fecal occult blood, flexible sigmoidoscopy, colonoscopy, and double contrast barium enema), computed tomographic colonography (virtual colonoscopy) and stool-based molecular screening are under development. Four classes of chemopreventive compounds have demonstrated efficacy in reducing recurrent colorectal adenomas and/or cancer in randomized, controlled trials. They are selenium, calcium carbonate, hormone replacement therapy, and nonsteroidal anti-inflammatory drugs. The mechanisms of action of nonsteroidal anti-inflammatory drugs include inhibition of the cyclooxygenase system as well as cyclooxygenase-independent effects. Considerable effort is being expended to define chemopreventive activity, optimal dose, administration schedule, and toxicity for the coxibs in adenoma recurrence prevention trials. The threshold for tolerating toxicities is very low in asymptomatic individuals at minimally increased risk for colorectal neoplasia.  相似文献   
86.

Objective

To identify patient demographic and clinical characteristics associated with osteoarthritis (OA) treatment use.

Methods

This was a secondary data analysis of 3 clinical trials among patients with hip or knee OA conducted in Duke Primary Care practices, the Durham Veterans Affairs (VA) Health Care System, and the University of North Carolina–Chapel Hill (UNC). At baseline, participants reported sociodemographic characteristics, OA‐related pain and function, and OA treatment use, including oral analgesics, topical creams, joint injections, and physical therapy. Separate, multivariable logistic models (adjusted for clustering of clinics and providers for the Duke and VA cohorts) were used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs) for the associations between participant characteristics and each type of OA treatment.

Results

Oral analgesic use was reported by 70–82% of participants across the 3 cohorts. Physical therapy, knee injections, and topical creams were used by 39–52%, 55–60%, and 25–39% of Duke, VA, and UNC participants, respectively. In multivariable models, worse pain, stiffness, and function, per 5‐unit increase, were associated with greater odds of using any oral analgesic for the cohorts from Duke (OR 1.18 [95% CI 1.08–1.28]) and UNC (OR 1.14 [95% CI 1.05–1.24]), but not for the VA cohort (OR 1.04 [95% CI 0.95–1.14]). For all 3 cohorts, nonwhites had higher odds of using topical creams compared to whites.

Conclusion

Results suggest potential underutilization of therapies other than oral analgesics. Patient characteristics may affect OA treatment use, and understanding the relationship between these factors and OA treatment preferences may improve adherence to OA treatment guidelines.  相似文献   
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