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Depletion neutropenia caused by overwhelming bacterial infection is associated with fatal outcome and is an objective indicator of the severity of sepsis. Studies on controlled evaluation of exchange transfusion in the management of severe neonatal sepsis have not considered neutropenia as an inclusion critcrion, and randomized, controlled trials on evaluation of ncutrophil functions after exchange transfusion are scarce. This prompted us to carry out the present study. Septicemic neonates were enrolled if they had neutropenia and were randomized to undergo exchange transfusion (study group, n = 20) or not (controls, n= 10). Granulocyte functions were assessed using the nitro blue tetrazolium (NBT) reduction test and the staphylococcicidal index. Blood was drawn for granulocyte function tests once from controls and donors, and before, immediately after and 6 h after exchange transfusion in the study group. Mortality was 35% in the study group and 70% in controls. Gram-negative organisms accounted for 80%, in the study group and 90% in controls. Mean total leukocyte count and neutrophil count increased significantly immediately after exchange transfusion and 6 h later. Absolute band count decreased significantly immediately after exchange transfusion and incrcased 6 h later. NBT reduction in septicemic neonates in the study group, as wclras in controls. was significantly decreascd as compared to donor cells. NBT reduction improved significantly immediately after exchange transfusion and 6 h later. The valucs of the perccntage of viable staphylococci recovered from neutrophils also improved significantly immediately after exchange transfusion and 6 h later. We conclude that exchange transfusion with fresh whole blood in severe neonatal septicemia with neutropenia improves survival, increases the neutrophil count and cnhances neutrophil function.  相似文献   
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PURPOSE: The purpose of this study was to assess the diabetes risk status, incidence, and morbidity within San Diego's Chamorro community as a foundation to help community leaders and health care providers create culturally customized health promotion interventions. METHODS: The Behavioral Risk Factor Surveillance Survey was used to query a randomly selected, convenience sample of San Diego Chamorros (N = 228) drawn from the Chamorro Directory International. Based on individual survey responses, participants were mailed personalized health-promoting information. Subsequently, they received information that addressed the most commonly observed overall threats to the Chamorro community's health. RESULTS: A higher than average prevalence of diabetes and gestational diabetes was reported by study participants along with a high prevalence of the risk factors associated with the premature onset of diabetes and its consequences. CONCLUSION: Collaborative partnerships between health professionals and community leaders can help identify opportunities and strategies for improving the health of the nation's population subgroups. San Diego's Chamorro community leaders now have a clearer understanding of the prevalence of diabetes risk factors within their community and can begin working with public health educators to create culturally aligned diabetes prevention and management programs. Given the willingness of Chamorro leaders to get involved in the development of a diabetes awareness campaign and the community's closely knit social network, it should be possible to promote (1) community participation in the intervention program, (2) an increase in the community's adherence to recommended behavioral changes, and (3) identification of additional program modifications that will further enhance the program's cultural relevance.  相似文献   
76.
RATIONALE: Usual interstitial pneumonia (UIP) is characterized by extracellular matrix deposition and the development of pulmonary fibrosis. Fibroblastic foci found in the lung are believed to represent an early stage in the evolution of this disease. OBJECTIVES: To compare gene expression profiles in different components of lung tissue (fibroblastic foci, adjacent epithelium, and areas of type 2 pneumocyte hyperplasia) from patients with UIP, and contrast these profiles to distal, uninvolved (control) alveolar tissue from patients undergoing lung resection for cancer. METHODS: Lung resection tissue (UIP, n = 11; controls, n = 11) was snap-frozen for subsequent laser capture microdissection, followed by mRNA extraction, linear amplification, and quantitative real-time polymerase chain reaction. RESULTS: In patients with UIP, tissue inhibitor of matrix metalloprotease-1 and matrix metalloprotease (MMP)-2 gene expression was up-regulated within the fibroblastic foci compared with the overlying epithelium (p = 0.03, p = 0.02), and to control alveoli (p = 0.001, p = 0.04), respectively. MMP-9 and MMP-7, as well as osteopontin, were up-regulated in fibroblastic foci (p = 0.01, p = 0.08, p = 0.08), the adjacent epithelium (p = 0.001, p = 0.001, p = 0.03), and the hyperplastic type 2 pneumocytes (p = 0.02, p = 0.001, p = 0.08), respectively, compared with control alveoli. CONCLUSION: Altered gene expression of important profibrotic mediators in the different cellular lung compartments in patients with UIP likely plays an important role in pathogenesis of the deranged extracellular matrix deposition and subsequent fibrosis in this condition.  相似文献   
77.
The recent increase in the incidence of ectopic pregnancies was associated with rapid improvement in the diagnostic and therapeutic techniques. Quantitative serum B-HCG radioimmunoassay and high resolution vaginal ultrasonography have facilitated early diagnosis of ectopic pregnancy allowing a more conservative approach to patient management. Different conservative surgical and medical lines of management recently developed were associated with and increased chance of subsequent intrauterine pregnancy with no increase in the incidence of repeat ectopic pregnancy. Outpatient systemic medical treatment seems to be a preferred alternative to conservative surgery. In selected cases, it is associated with a lower complication rate and promising result for fertility. (Br J Clin Pract 1996; 50(7) : 376-380.)  相似文献   
78.
Diarrhea is a leading cause of morbidity and mortality in people living with HIV (PLHIV) in Africa. The impact of a point-of-use water chlorination and storage intervention on diarrheal-disease risk in a population of HIV-infected women in Lagos, Nigeria was evaluated. A baseline survey was performed, followed by six weeks of baseline diarrhea surveillance consisting of weekly home visits, distribution of free water chlorination products and safe storage containers to project participants, and continued weekly home-based diarrhea surveillance for 15 additional weeks. To confirm use of the water chlorination product, during each home visit, stored water was tested for residual chlorine. About 187 women were enrolled. At baseline, 80% of women had access to improved water supplies and 95% had access to sanitation facilities. Following distribution of the intervention, water stored in participants' households was observed to have residual chlorine during 50-80% of home visits, a sign of adherence to recommended water-treatment practices. Diarrhea rates in project participants were 36% lower in the post-intervention period than during the baseline period (p=0.04). Diarrhea rates were 46% lower in the post-intervention period than the baseline period among project participants who were confirmed to have residual chlorine in stored water during 85% or more of home visits (p=0.04); there was no significant difference in diarrhea rates between baseline and post-intervention periods in participants confirmed to have residual chlorine in stored water during less than 85% of home visits. The percent change in diarrhea rates between baseline and post-intervention surveillance periods was statistically significant among non-users of prophylactic antibiotics (-62%, p=0.02) and among persons who used neither prophylactic antibiotics nor antiretroviral treatment (-46%, p=0.04). Point-of-use water treatment was associated with a reduced risk of diarrhea in PLHIV. Regular water treatment was required to achieve health benefits.  相似文献   
79.
Interference Competition and Niche Theory   总被引:9,自引:1,他引:9       下载免费PDF全文
A linear model of interspecific competition with separate parameters for exploitation and interference is deduced. Interference is assumed to have a cost and an effect. The interfering species realizes a “profit” if some resources, which the species interfered against would have utilized, are made available as a result of the interference. Interference is favored when its cost is small, its effect is high, and the resource overlap with the species interfered against is high. Interference is likely to be an alternative strategy to high exploitation efficiency. The incorporation of interference into niche theory clarifies the competitive phenomenon of unstable equilibrium points, excess density compensation on islands, competitive avoidance by escape in time and space, the persistence of the “prudent predator,” and the magnitude of the difference between the size of a species' fundamental niche and its realized niche.  相似文献   
80.
SETTING: New cases of pulmonary tuberculosis (TB) were noted in a cluster of young Caucasian males, an unusual ethnic group for this disease in Queensland, Australia. It was noted that marijuana water pipe ('bong') smoking was common amongst cases and contacts. OBJECTIVE: To report this cluster of TB and to investigate whether shared use of a marijuana water pipe was associated with transmission of TB. DESIGN: All contacts were identified and screened according to standard protocols. Cases were asked to list contacts with whom they had shared a marijuana water pipe. RESULTS: Five cases of open pulmonary TB were identified clinically and on sputum culture, and all isolates of Mycobacterium tuberculosis were identical on typing. Of 149 contacts identified, 114 (77%) completed screening, and 57 (50%) had significant tuberculin skin test (TST) reactions on follow-up. Of 45 contacts who had shared a marijuana water pipe with a case, 29 (64%) had a significant TST reaction. CONCLUSION: Sharing a marijuana water pipe with a case of pulmonary TB was associated with transmission of TB (OR 2.22, 95 % CI 0.96-5.17), although the most important risk factor for acquiring TB infection in this cluster was close household contact with a case (OR 4.91, 95% CI 1.13-20.70).  相似文献   
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