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排序方式: 共有943条查询结果,搜索用时 15 毫秒
1.
Gabriela Perdomo Coral Angelo Alves de Mattos 《Journal canadien de gastroenterologie》2003,17(3):187-190
BACKGROUND/AIMS: Spontaneous bacterial peritonitis (SBP) is an important complication in cirrhotic patients. The aim of the present study was to assess the incidence, predictive factors and prognosis for renal impairment (RI) after SBP in cirrhotic patients from southern Brazil. METHODS: Of the 1030 hospitalizations evaluated, 114 episodes of SBP were diagnosed in 94 patients (mean age 49 years; 76.59% men). SBP diagnosis was established when the ascitic fluid polymorphonuclear cell count was equal to or greater than 250 cells/mm3. Five cases were excluded. The variables assessed as possible predictors of steady or progressive RI were blood urea nitrogen and creatinine levels before the diagnosis of SBP; type of infection, antibiotic prophylaxis, first episode or recurrent SBP, presence of gastrointestinal bleeding and hepatic encephalopathy during hospitalization, SBP resolution, Child-Pugh classification, levels of blood pressure, ascitic fluid and blood polymorphonuclear cell count, bacteriological data (positive and negative ascitic fluid culture), albumin, bilirubin, sodium and prothrombin time at the moment of diagnosis. RESULTS: The incidence of SBP was 11.07%. In 61 (55.96%) episodes, SBP was associated with RI (transient in 57.37%; steady in 19.67%; and progressive in 22.95%). The mortality rate associated with progressive RI was 100%; 58.33% with steady RI; and 2.85% with transient RI. The mortality rate in patients with or without RI was 36.07% and 6.25%, respectively (P<0.001). The level of creatinine (greater than or equal to 1.3mg/dL) before the diagnosis of SBP and the rate of infection resolution were the only predictors of RI in the multivariate analysis. CONCLUSIONS: RI after SBP is a common complication, and indicates a poor prognosis for this infection. High levels of creatinine before infection and the rate of infection resolution are independent predictors of RI. 相似文献
2.
Gregor McWalter MA MSc Hugh Toner MA DipCouns MSc CPsychol Alison Corser BSc MPhil CPsychol Jenny Eastwood MBChB DipSocMed FRCPsych Mary Marshall MA DSA DASS Tony Turvey BSc MAppSci CPsychol 《Health & social care in the community》1994,2(4):213-219
The concept of need and the practice of needs assessment are both subject to a wide range of interpretations, to the likely detriment of individual assessments and to multidisciplinary working. Clear definition is important for individual assessment, for the development of multidisciplinary tools and in gathering planning information. The concept of need is clarified, firstly by distinguishing between need and the difficulties that engender it, and secondly through a taxonomy of need. These assist clear definitions of both need and needs assessment when linked with a consideration of the current help a person receives and a specification of the type of help required by a person to meet their needs. Such definitions have implications for the role of needs assessment in individual assessment, service evaluation, service management and planning and in the development of multidisciplinary needs assessment tools. 相似文献
3.
R Yip I Parvanta K Scanlon E W Borland C M Russell F L Trowbridge 《Morbidity and mortality weekly report. Surveillance summaries (Washington, D.C. : 2002)》1992,41(7):1-24
The CDC Pediatric Nutrition Surveillance System (PedNSS) monitors the general health and nutritional characteristics of low-income U.S. children who participate in multiple public health programs. This system is intended to characterize trends and patterns in key indicators of nutritional status so that the information can be used for program planning and targeting. The indicators monitored by PedNSS are birth weight, childhood growth status, anemia, and breast-feeding patterns. From 1980 through 1991, the trends for low birth weight, low height-for-age (shortness), low weight-for-height (thinness), and high weight-for-height (overweight) were stable for all children monitored by the PedNSS, with the exception of Asian children, who were predominantly of Southeast Asian refugee background. In the early 1980s, the prevalence of low birth weight and shortness was higher among Asian children than among children of other racial or ethnic groups who were monitored by the PedNSS. However, these prevalences declined steadily from 1980 through 1991. By 1991, the prevalences of low birth weight and shortness for Asian children were similar to those observed for children of other races/ethnic groups. Overall, low-income U.S. children had a slightly lower height-for-age than expected, indicating that some of these children were at a health and nutritional disadvantage. The prevalence of overweight varied among different racial/ethnic groups; Hispanic and Native American children had the highest prevalences of overweight. The 20%-30% prevalence of anemia among low-income children monitored by the PedNSS was higher than among the general population, reflecting in part the preferential enrollment and retention of anemic children by public health nutrition programs and also indicating that many children had inadequate iron nutrition. From 1980 through 1991, the prevalence of anemia declined > 5% for most of the age- and race/ethnicity-specific groups monitored by PedNSS. That decline represents an improvement in iron nutritional status. PedNSS is a useful system for the monitoring and characterization of the nutrition status of low-income children at both state and national levels. 相似文献
4.
Jose Rodriguez Wendy Jacques-Berg Coral Sanfeliu Ambrish J. Patel 《Brain research》1992,590(1-2):109-117
The possible involvement of ionotropic and metabotropic quisqualate (QA) receptors in neuronal plasticity was studied in cultured glutamtergic cerebellar or hippocampal cells in terms of the specific activity of phosphate-activated glutaminase, an enzyme important in the synthesis of the putative neurotransmitter pool of glutamate. When cerebellar of hippocampal neurons were treated with QA, it elevated the specific activity of glutaminase in a dose-dependent manner. The half-maximal effect was obtained at about 0.1 μM, the maximum increase was at about 1 μM, but levels higher than 10 μM QA produced progressive reduction in glutaminase activity. In contrast, QA had little effects on the activities of lactate dehydrogenase and aspartate aminotransferase and the amount of protein, indicating that the increase in glutaminase was relatively specific. The QA-mediated increase in glutaminase was mimicked by the ionotropic QA receptor agonist -amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA; EC50, about 0.5 μM), but not by the metabotropic QA receptor agonist trans-(±)-1-aino-cyclopentyl-1,3,dicarboxyalte (t-ACPD; up to 0.5 mM). The specific ionotropic QA receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) inhibited QA- and AMPA-mediated increases in glutaminase activity in a dose-dependent manner, whereas other glutamate receptor antagonists,
-2-amino-5-phosphonovalerate, γ-
-glutamyl aminomethyl sulphonic acid and γ-
-glutamyl diethyl ester were ineffective. The elevation of neurotransmitter enzyme was Ca2+-dependent. The increase in Ca2+ influx essentially through the activation of L-type voltage-operated Ca2+ channels, and not the mobilization of internal Ca2+ stores, was responsible for these QA receptor-mediated long-term plastic changes in hippocampal and cerebellar neurons. 相似文献
5.
Coronary thrombosis and platelet/fibrin microemboli in death associated with acute myocardial infarction. 总被引:1,自引:0,他引:1
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The frequency and clinical significance of platelet/fibrin microemboli in the microcirculation were investigated in 24 patients whose deaths (before and during hospital admission) were associated with acute myocardial infarction. An acute coronary thrombus was present in all the hearts. In nine hearts an acute thrombus was found in more than one major epicardial coronary artery. A total of 35 acute thrombi were found in the 24 hearts. Platelet/fibrin microemboli were found in 19 (79%) hearts. Eighteen patients died in hospital. The hearts of 16 of these cases showed microemboli; 16 had important arrhythmias or various forms of heart block; 13 showed acute pathological changes in the conduction system. Fourteen of the deaths in hospital were primarily the result of cardiogenic shock and four were primarily caused by arrhythmia. Six of the deaths that occurred before admission to hospital were regarded as being arrhythmic in origin. Three of these showed microemboli and the other three had acute pathological changes in the conduction system. Microemboli were found in two (24%) of 12 control hearts. Coronary thrombosis was found in most deaths caused by acute myocardial infarction and platelet/fibrin microemboli were present in the majority of such hearts. These may arise from the coronary thrombus in the larger upstream vessel supplying the microcirculation. 相似文献
6.
A method for evaluating systems of epidemiological surveillance 总被引:3,自引:0,他引:3
S B Thacker R G Parrish F L Trowbridge 《Rapport trimestriel de statistiques sanitaires mondiales》1988,41(1):11-18
Epidemiological surveillance is the systematic collection, analysis and dissemination of health data for the planning, implementation and evaluation of public health programmes. Established surveillance systems should be regularly reviewed on the basis of explicit criteria of usefulness, cost and quality; systems should be modified as a result of such review. Attributes of quality include: (i) sensitivity, (ii) specificity, (iii) representativeness, (iv) timeliness, (v) simplicity, (vi) flexibility and (vii) acceptability. To date, evaluation of surveillance systems has been limited in scope and content. The evaluation method proposed in this article offers an organized approach to the evaluation of epidemiological surveillance systems. The usefulness of a surveillance system is measured by whether it leads to prevention or control or a better understanding of adverse health events. The measure can be qualitative, in terms of the subjective views of those using the system, or quantitative in terms of the impact of surveillance data on policies, interventions or the occurrence of a health event. The cost of a system includes indirect as well as direct costs, and should be measured in relation to the benefits obtained, such as reduction of medical-care expenses and of time lost from work. All elements of the system should be included in the cost: data collection, analysis and dissemination. The sensitivity of a surveillance system is its ability to detect health events (completeness of reporting). Its specificity is inversely proportional to the number of false positives it reports. Reports of a disease that do not meet the case definition are false positives, and may result in resources being wasted in investigating them.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
7.
Susan Kirk MSc BNurs RGN RM RHV DNCert Caroline Carlisle MSc BA RGN RM DNCert DipCouns RNT Karen A. Luker PhD BNurs RGN RHV DNCert 《Journal of advanced nursing》1997,26(5):1036-1044
A national study was conducted between 1991 and 1994 to explore and describe the changing role of the nurse teacher following the introduction of Project 2000 pre-registration nursing courses. Multiple methods were used to collect data from a wide variety of respondents (nurse teachers, midwife teachers, clinical nurses, health service managers and higher education lecturers). This paper presents the findings relating to the impact of Project 2000 and the move into higher education on the continuing educational needs of nurse teachers. Views on college strategies for staff development, the changing nature of teachers'academic and professional development needs and the problems of the conflicting demands experienced are reported. The research highlights the need for clinical credibility to be clearly defined in relation to nurse teachers and for educational institutions to place more emphasis on teachers'clinical development if the rhetoric of policy is to become a reality. 相似文献
8.
Bronchoalveolar lavage cell counts as a predictor of short term outcome in pulmonary sarcoidosis. 总被引:1,自引:1,他引:0
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Sixty seven patients with biopsy proven pulmonary sarcoidosis were prospectively studied to determine whether single point bronchoalveolar lavage cell counts were a useful indicator of functional outcome and whether repeated lavage helped in management. The mean follow up period was 25 (range 13-37) months. No patient was having corticosteroid treatment at the time of initial bronchoalveolar lavage. "High intensity alveolitis" (lymphocyte count greater than or equal to 28%) was present at the initial lavage in 42 patients. These patients showed a significant improvement in their pulmonary function and chest radiographs over the follow up period whereas patients with "low intensity alveolitis" did not. Of the 42 patients with high intensity alveolitis, 31 had chronic sarcoidosis (duration over two years, mean 80 months). These patients showed a significant improvement in FVC but not in TLCO. Corticosteroids resulted in greater functional and radiological improvement in the patients with high intensity alveolitis than in those with low intensity alveolitis. Repeat bronchoalveolar lavage in 34 patients, mean 8.4 months after the original lavage, showed a weak inverse relation between a reduced lymphocyte count and change in forced vital capacity and isotope uptake on a gallium scan. These correlations were too weak to make repeated cell counts useful in management. Our results suggest that high intensity alveolitis may be a favourable prognostic factor for lung function in pulmonary sarcoidosis, even in patients with chronic disease, but that repeat lavage adds little to the management of the individual patient. 相似文献
9.
Immunological properties of murine thymus-dependent lymphocyte surface glycoproteins. 总被引:9,自引:0,他引:9
The immunological properties of two murine thymus-dependent (T) lymphocyte surface glycoproteins, T200 and T25, were investigated. T200 is a lymphocyte-specific antigen with a high degree of species specificity. It shares antigenic determinants with molecules present on thymus-independent (B) lymphocytes. T25 has antigenic determinants which cross-react with antigens on mouse brain, rat thymocytes and rat brain. An antiserum against a purified rat brain glycoprotein which carries Thy-1.1 reacts with T25. Absorption of this antiserum with BALB/c thymocytes or brain homogenate produces a Thy-1.1 specific serum which reacts with T25 from AKR/J thymocytes but not with T25 from AKR/Cum thymocytes. These results confirm that T25 is the molecule on the surface of mouse T cells which carries the Thy-1 antigen. T25 also carries antigenic determinants, recognized by anti-thymocyte serum (ATS), which were found on secondary mouse embryo fibroblasts and untransformed fibroblast cell lines but which were not detected on fibroblast cell lines transformed with murine sarcoma virus (MSV) or with Simian virus 40 (SV40). 相似文献
10.
Arenaviruses: Cellular Response to Long-Term In Vitro Infection with Parana and Lymphocytic Choriomeningitis Viruses 总被引:4,自引:2,他引:4
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L. D. Staneck R. S. Trowbridge R. M. Welsh E. A. Wright C. J. Pfau 《Infection and immunity》1972,6(4):444-450
Persistent infections were established in suspension cultures of BHK21/13S cells with both Parana and lymphocytic choriomeningitis viruses. Four generations after infection with either virus, more than 90% of the cells scored as infective centers, with concomitant peaks in extracellular virus yields. In both cultures the synthesis of detectable plaque-forming units (PFU) ceased about the 50th generation postinfection, and this condition was maintained until the 350th cell generation when the cultures were discontinued. The generation time of each culture was identical to that of uninfected parent controls, and at no time were cytopathic effects evident. In spite of the absence of infectivity, over 90% of the cells sampled at various times contained viral antigen demonstrable by immunofluorescence. When either of these persistently infected cell lines was substituted for normal cells in the standard plaque assay, very low efficiencies of plating were observed for homotypic and heterotypic viruses. Plaque formation by several heterologous viruses was virtually unaffected. The mechanism of homotypic plaque exclusion in both cell lines was shown to occur beyond the virion adsorption stage. The original infecting virus genome persisted in both cell lines after standard virus was no longer detectable. This was shown with the lymphocytic choriomeningitis virus-infected cells after storage in liquid nitrogen. After thawing, such cells were found to synthesize standard virus for a brief period. Although the Parana virus-infected cells did not behave this way, the growth medium from these cells would initiate PFU synthesis in normal cells within 36 hr after infection. 相似文献