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1.
Suppurative corneal ulceration in Bangladesh   总被引:8,自引:0,他引:8  
Suppurative keratitis is an important preventable cause of blindness, particularly in the developing world. This study analyses 142 cases of suppurative keratitis referred to Chittagong Eye Infirmary, Bangladesh. Some 53.5% of cases were bacterial and 35.9% were fungal. The five most common pathogens were: Pseudomonas sp. 24%, Streptococcus pneumoniae 17%, Aspergillus sp. 13%, Fusarium sp. 7% and Curvularia sp. 6%. Gram stain and culture results were consistent in 62.6% of cases. Previous antibiotic treatment was a significant factor for failure of culture isolation and less so for Gram stain failure. On Gram stain, 55.9% of pseudomonal cases were missed, but only 2% of fungal cases were missed. Over all, Gram stain had a sensitivity of 62% and positive predictive value of 84% for bacterial cases, and 98% and 94% for fungal cases, respectively. Fungal ulcers were typically filamentous, but an antecedent history of trauma was not common. The most frequent injury was due to rice grains, but the inoculum appeared to be introduced during eye washing with contaminated water. Pseudomonal ulcers occurred most frequently in the monsoon season, and Fusarium cases were seen only in the hot, dry season.  相似文献   
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. We invited Dr Peplau to provide a personal reflection on the recent history of psychiatric nursing and her thoughts on immediate challenges facing the profession. The paper is an individual scholar's commentary on the way that psychiatry has waxed and waned over the years, in relation to nursing. This historical review discovers and reports a challenge to current practice. Dr Peplau describes a professional shift that is pulling nurses toward the subordinate role observed earlier this century. The paper draws attention to how contemporary practice can be positively influenced, e.g., by giving a structure to the allocation and conduct of nurse–patient time.  相似文献   
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OBJECTIVE: It has been suggested that keratinocyte (KC) stem cells reside at the epicenter of a clonal population of cells. To estimate the territory or surface area covered by a single stem-cell-derived KC population in human skin, clonal skin maps were created from 3 healthy adult women and from normal skin of a psoriatic patient. DESIGN: Two hundred fifty-eight punch biopsy samples of various sizes (ranging from 2 to 8 mm in diameter) were analyzed for clonality employing X chromosome inactivation patterns at the human androgen receptor gene (HUMARA) locus. DNA was isolated and clonality established by significant decrease of either maternal or paternal X chromosome band patterns following restriction enzyme digestion, polymerase chain reaction amplification, and gel electrophoresis. RESULTS: Fifty-three (41%) of 128 two-mm biopsies were clonal, whereas only 6 (14%) of 43 three-mm, 5 (14%) of 36 four-mm, and 3 (8%) of 35 five-mm biopsies revealed a clonal population of KCs. By contrast, in 5 different biopsies from a psoriatic patient, including 4- or 5-mm sizes, all but 1 were clonal; even an 8-mm biopsy contained a clonal population of KCs. Mantel-Haenszel chi(2) analysis revealed a P value of.001, reflecting a strong trend in probability for presence of a single clone of KCs as related to size of the biopsy sample. By sequentially analyzing 30 contiguous 2-mm biopsy samples within a given strip of skin, 10 clonal domain changes, as reflected in maternal versus paternal switches, were observed. CONCLUSIONS: These results provide direct evidence of a clonal population of KCs in normal and psoriatic lesion-free skin, and indicate that a clonal epidermal unit of KCs frequently can be detected in small biopsies (2 mm), but that in normal skin sampling, overlapping clones are apparently present in larger (ie, 4-5-mm) biopsies, producing nonclonal patterns. The clonal domain of progeny in normal skin has a rather limited territorial boundary (2 mm in diameter). However, in lesion-free skin from a psoriatic patient, there may be clonal expansion of KCs due to perturbation in epidermopoiesis and/or stem cell distribution.  相似文献   
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Because of increasing competition, it is becoming more important that health care providers pursue consumer-based market segmentation strategies. This paper presents a methodology for identifying and describing consumer segments in health service markets, and demonstrates the use of the methodology by presenting a study of consumer segments in the ambulatory care pharmacy market.  相似文献   
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Exposure to heterocyclic amines may increase prostate cancer risk. Human sulfotransferase 1A1 (SULT1A1) is involved in the bioactivation of some dietary procarcinogens, including the N-hydroxy metabolite of the food-borne heterocyclic amine, 2-amino-1-methyl-6-phenylimidazo(4,5-b) pyridine. This study compares a polymorphism in the SULT1A1 gene, SULT1A1 enzyme activity, meat consumption, and the risk of prostate cancer in a population based case-control study. Prostate cancer patients (n = 464) and control individuals (n = 459), frequency matched on age and ethnicity, provided informed consent, answered a survey, and provided a blood sample. Platelets were isolated for phenotype analysis, and DNA was isolated from lymphocytes for genotype determination. Meat consumption was assessed using a dietary questionnaire. Caucasians homozygous for the SULT1A1*1 high activity allele were at increased risk for prostate cancer [odds ratio (OR), 1.68; 95% confidence interval (CI), 1.05-2.68] compared with individuals homozygous for the low-activity allele. The association between SULT1A1 genotype and prostate cancer risk in African-Americans did not reach significance (OR, 1.60; 95% CI, 0.46-5.62). When SULT1A1 activity was considered, there was a strong association between increased SULT1A1 activity and prostate cancer risk in Caucasians (OR, 3.04; 95% CI, 1.8-5.1 and OR, 4.96; 95% CI, 3.0-8.3, for the second and third tertiles of SULT1A1 activity, respectively) compared with individuals in the low enzyme activity tertile. A similar association was also found in African-American patients, with ORs of 6.7 and 9.6 for the second and third tertiles of SULT1A1 activity (95% CI, 2.1-21.3 and 2.9-31.3, respectively). When consumption of well-done meat was considered, there was increased risk of prostate cancer (OR, 1.42; 95% CI, 1.01-1.99 and OR, 1.68; 95% CI, 1.20-2.36 for the second and third tertiles, respectively). When SULT1A1 activity was stratified by tertiles of meat consumption, there was greater risk of prostate cancer in the highest tertile of meat consumption. These results indicate that variations in SULT1A1 activity contributes to prostate cancer risk and the magnitude of the association may differ by ethnicity and be modified by meat consumption.  相似文献   
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Seventy-five patients, 13 to 49 years of age, with acute nonlymphoblastic leukemia in first remission were treated with cyclophosphamide, fractionated total body irradiation, and marrow transplantation from an HLA-identical sibling and randomized to receive either cyclosporine (CSP) (n = 36) or methotrexate (MTX) (n = 39) as prophylaxis for graft-v-host disease (GVHD). All patients engrafted, and 22 who were given CSP and 21 who were given MTX, are alive at 20 to 47 (median, 35) months (P = .5). Engraftment as assessed by granulocyte recovery (P less than .0005) and platelet transfusion requirement (P = .01) was faster in patients on CSP. Twelve patients (33%) on CSP and 22 (56%) on MTX developed acute GVHD of grades II through IV (P = .07) and 15 of 30 on CSP and 14 of 32 on MTX that were at risk developed chronic GVHD. The most frequent causes of death were interstitial pneumonitis and marrow relapse of leukemia, which occurred with similar frequency in both groups. Beneficial effects observed in patients on CSP included less severe mucositis and shorter duration of hospitalization; adverse effects included renal function impairment and hypertension. These data confirm that CSP is a useful immunosuppressant in patients undergoing marrow transplantation but fail to show a significant improvement in survival as compared with the standard regimen of MTX.  相似文献   
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