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71.
In April 1998 an outbreak of salmonellosis amongst guests at a wedding feast was investigated. Of the 58 attendees interviewed 38 (66%) subsequently developed gastrointestinal symptoms. Stool cultures from 7 cases grew Salmonella Typhimurium RDNC A045. Food samples were culture-negative for Salmonella spp. A cohort study implicated spatchcock (RR 2.5, 95% CI 1.09-5.77) and scampi (RR 2.0, 95% CI 1.05-3.89). Temperature abuse and cross-contamination within the kitchen during preparation and cooking are likely to have been the main contributing factors to this outbreak. Control measures included staff education in safe food handling and improvements in poultry processing methods to minimise carcass contamination.  相似文献   
72.
Creutzfeldt-Jacob disease manifests clinically as a form of presenile dementia. It is now known to be caused by a transmissible agent, probably a "slow virus". Rapidly progressive atrophic changes on serial computed tomograms of the brain are highly suggestive of the disease. Neuroradiographic and pathological findings in two cases of Creutzfeldt-Jacob disease are documented.  相似文献   
73.
Brigham and Women's Hospital initiated a study of the quality of care centering on self-reporting of potential medical injuries by providers. The goal of the study is to decrease the incidence of such injuries through a continuous quality methodology that integrates providers into the identification phase and incorporates all hospital employees in the development of new practices. This article provides an overview of the investigation methodology and discusses the conceptual relationships between clinical epidemiological analyses and industrial quality improvement.  相似文献   
74.
Changes in serum zinc and copper levels were studied in 19 tumor bearing patients undergoing parenteral nutrition (TPN) for five to 42 days. Before initiation of intravenous feeding mean serum zinc and copper concentrations were within normal limits but during TPN levels decreased significantly below those measured prior to parenteral nutrition. During TPN nitrogen, zinc, and copper intake, urinary output and serum levels were studied prospectively in nine of these patients. These nine patients exhibited positive nitrogen retention based upon urinary nitrogen excretion, but elevated urinary zinc and copper excretion and lowered serum zinc and copper concentrations. Neither blood administration nor limited oral intake was consistently able to maintain normal serum levels of zinc or copper. Zinc and copper supplementation of hyperalimentation fluids in four patients studied for five to 16 days was successful in increasing serum zinc and copper levels in only two. The data obtained suggest that patients undergoing parenteral nutrition may require supplementation of zinc and copper to prevent deficiencies of these elements.  相似文献   
75.
Validity of the tritiated water assay technique for tyrosine hydroxylase activity as a qualitative method was demonstrated with mushroom tyrosinase. Using this method, isolated murine melanoma "tyrosinase" (L-dopa oxidase) showed no tyrosine hydroxylase activity. This finding supports previous studies in our laboratory which used a variety of histochemical and biochemical methods. The nonenzymatic production of tritiated water caused by tritium exchange with hydrogen peroxide complicates the use of the tritiated water assay technique with crude systems, since hydrogen peroxide is generated by a variety of oxidase reactions. For this reason, previous studies using the tritiated water assay technique with crude systems are ambiguous.  相似文献   
76.
A booklet, "Assessment of Maternal Nutrition," has been published by the American College of Obstetricians and Gynecologists in cooperation with The American Dietetic Association as a useful guide for physicians, nurses, dietitians, and nutritionists. Nutritional risks during pregnancy are clearly outlined. Clinical, dietary, and biochemical factors, as well as medical, obstetric, and social factors, are delineated as components of nutritional assessment. An A.D.A. Liaison Committee had major responsibility for the development of the "Eating Habits Questionnaire," a tool to screen dietary intake for major deficits and excesses, which is included in the booklet. It should be useful also as a starting point for nutrition education. Additional evaluation of the use and reliability of the screening tool is recommended.  相似文献   
77.
A randomised controlled trial was carried out on 100 patients to compare the effects of discharge after certain pre-specified clinical criteria had been fulfilled--"right" stay--with those of discharge at an arbitrary 10 days after surgery--"fixed" stay. The operations concerned (cholecystectomy and vagotomy) were more hazardous than those previously included in studies of early discharge. Patients in the right-stay group were discharged, on average, 7-6 days after operation--that is, two days earlier than those in the fixed-stay group. In terms of clinical progress, social factors such as return to work, and the acceptability to patients and relatives of the implications of right stay, patients in this group fared as well as those in the fixed-stay group, and in some respects slightly better. Right stay entailed the transfer of some work from hospital to community medical and nursing staff, but this also was acceptable. The concept and use of the right-stay principle is of value in planning the postoperative discharge of suitable patients.  相似文献   
78.
79.
PURPOSE: To develop a genome-based classification scheme for clear-cell sarcoma (CCS), also known as melanoma of soft parts (MSP), which would have implications for diagnosis and treatment. This tumor displays characteristic features of soft tissue sarcoma (STS), including deep soft tissue primary location and a characteristic translocation, t(12;22)(q13;q12), involving EWS and ATF1 genes. CCS/MSP also has typical melanoma features, including immunoreactivity for S100 and HMB45, pigmentation, MITF-M expression, and a propensity for regional lymph node metastases. MATERIALS AND METHODS: RNA samples from 21 cell lines and 60 pathologically confirmed cases of STS, melanoma, and CCS/MSP were examined using the U95A GeneChip (Affymetrix, Santa Clara, CA). Hierarchical cluster analysis, principal component analysis, and support vector machine (SVM) analysis exploited genomic correlations within the data to classify CCS/MSP. RESULTS: Unsupervised analyses demonstrated a clear distinction between STS and melanoma and, furthermore, showed that CCS/MSP cluster with the melanomas as a distinct group. A supervised SVM learning approach further validated this finding and provided a user-independent approach to diagnosis. Genes of interest that discriminate CCS/MSP included those encoding melanocyte differentiation antigens, MITF, SOX10, ERBB3, and FGFR1. CONCLUSION: Gene expression profiles support the classification of CCS/MSP as a distinct genomic subtype of melanoma. Analysis of these gene profiles using the SVM may be an important diagnostic tool. Genomic analysis identified potential targets for the development of therapeutic strategies in the treatment of this disease.  相似文献   
80.
Sarcomas--like leukemias, which are also mesodermal malignancies--carry biological significance disproportionate to their clinical frequency. Identification of mutations and translocations associated with these tumors has illuminated aberrant signaling pathways that cause these diseases, determine their behavior, and are therapeutic targets. Activated receptor-associated tyrosine kinase c-kit, mutated in most gastrointestinal stromal tumors, has proven a clinically effective target for enzyme inhibition. A translocation involving a single gene family, consisting of EWS and related genes, has been identified in five different sarcomas, and its chimeric protein products could prove similarly amenable to inhibitors. Resolution of the histopathological complexity is being aided by data from molecular and chromosomal characterization. Improvements in imaging, definition of prognostic factors, and surgical and radiotherapeutic treatment have resulted in improved local control. Continued progress will depend on further adapting the rapidly evolving technologies of genomics and proteomics. It will also depend upon accurate histopathological diagnosis based on validated reagents and consistent methodologies applied to adequate tissue samples derived from patients with complete clinical data. Finally, multicenter, coordinated trials, such as those that occurred with assessment of imatinib mesylate in metastatic gastrointestinal stromal tumors, will assure the most rapid reductions in morbidity and mortality.  相似文献   
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