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Samples of cerebrospinal fluid from 103 patients with aseptic meningitis were tested by PCR for detection of leptospires, and the results were compared with those of the microscopic agglutination test (MAT) and an enzyme-linked immunosorbent assay for detection of immunoglobulin M (ELISA-IgM). Of these samples, 39.80% were positive by PCR and 8.74 and 3.88% were positive by MAT and ELISA-IgM, respectively.  相似文献   
996.
This paper reviews the performance of 10 previously reported patients who have deficits in recalling the names of people, but whose performance in recalling common names is relatively well preserved. An analysis of face naming ability in these 10 patients reveals that the proportion of faces that a patient can name is closely related to whether or not the patient has a retrieval problem that also extends to the recall of other types of proper names such as the names of towns. This analysis suggests that names of faces are particularly difficult to recall relative to other types of proper names, and provides no support for the view that a specialised brain mechanism is involved in the retrieval of people's names.  相似文献   
997.
Probabilistic models of human decompression sickness (DCS) have been successful in describing DCS risk observed across a wide variety of N2-O2 dives but have failed to account for the observed DCS incidence in dives with high PO2 during decompression. Our most successful previous model, calibrated with 3,322 N2-O2 dives, predicts only 40% of the observed incidence in dives with 100% O2 breathing during decompression. We added 1,013 O2 decompression dives to the calibration data. Fitting the prior model to this expanded data set resulted in only a modest improvement in DCS prediction of O2 data. Therefore, two O2-specific modifications were proposed: PO2-based alteration of inert gas kinetics (model 1) and PO2 contribution to total inert gas (model 2). Both modifications statistically significantly improved the fit, and each predicts 90% of the observed DCS incidence in O2 dives. The success of models 1 and 2 in improving prediction of DCS occurrence suggests that elevated PO2 levels contribute to DCS risk, although less than the equivalent amount of N2. Both models allow rational optimization of O2 use in accelerating decompression procedures.  相似文献   
998.
Inadequate management of blood pressure in a hypertensive population   总被引:1,自引:0,他引:1  
BACKGROUND: Many patients with hypertension have inadequate control of their blood pressure. Improving the treatment of hypertension requires an understanding of the ways in which physicians manage this condition and a means of assessing the efficacy of this care. METHODS: We examined the care of 800 hypertensive men at five Department of Veterans Affairs sites in New England over a two-year period. Their mean (+/-SD) age was 65.5+/-9.1 years, and the average duration of hypertension was 12.6+/-5.3 years. We used recursive partitioning to assess the probability that antihypertensive therapy would be increased at a given clinic visit using several variables. We then used these predictions to define the intensity of treatment for each patient during the study period, and we examined the associations between the intensity of treatment and the degree of control of blood pressure. RESULTS: Approximately 40 percent of the patients had a blood pressure of > or =160/90 mm Hg despite an average of more than six hypertension-related visits per year. Increases in therapy occurred during 6.7 percent of visits. Characteristics associated with an increase in antihypertensive therapy included increased levels of both systolic and diastolic blood pressure at that visit (but not previous visits), a previous change in therapy, the presence of coronary artery disease, and a scheduled visit. Patients who had more intensive therapy had significantly (P<0.01) better control of blood pressure. During the two-year period, systolic blood pressure declined by 6.3 mm Hg among patients with the most intensive treatment, but increased by 4.8 mm Hg among the patients with the least intensive treatment. CONCLUSIONS: In a selected population of older men, blood pressure was poorly controlled in many. Those who received more intensive medical therapy had better control. Many physicians are not aggressive enough in their approach to hypertension.  相似文献   
999.
BACKGROUND: H2 receptor blockers and proton pump inhibitors reduce intestinal output in patients with short bowel syndrome. AIMS: To evaluate the effect of intravenous omeprazole and ranitidine on water, electrolyte, macronutrient, and energy absorption in patients with intestinal resection. METHODS: Thirteen patients with a faecal weight above 1.5 kg/day (range 1.7-5.7 kg/day and a median small bowel length of 100 cm were studied. Omeprazole 40 mg twice daily or ranitidine 150 mg twice daily were administered for five days in a randomised, double blind, crossover design followed by a three day control period with no treatment. Two patients with a segment of colon in continuation were excluded from analysis which, however, had no influence on the results. RESULTS: Omeprazole increased median intestinal wet weight absorption compared with no treatment and ranitidine (p<0.03). The effect of ranitidine was not significant. Four patients with faecal volumes below 2.6 kg/day did not respond to omeprazole; in two absorption increased by 0.5-1 kg/day; and in five absorption increased by 1-2 kg/day. Absorption of sodium, calcium, magnesium, nitrogen, carbohydrate, fat, and total energy was unchanged. Four high responders continued on omeprazole for 12-15 months, but none could be weaned from parenteral nutrition. CONCLUSION: Omeprazole increased water absorption in patients with faecal output above 2.50 kg/day. The effect varied significantly and was greater in patients with a high output, but did not allow parenteral nutrition to be discontinued. Absorption of energy, macronutrients, electrolytes, and divalent cations was not improved. The effect of ranitidine was not significant, possibly because the dose was too low.  相似文献   
1000.
OBJECTIVE: To compare the efficacy of hydroxychloroquine, penicillamine, sodium aurothiomalate and auranofin in the treatment of active rheumatoid arthritis over a period of 5 yr. METHOD: Five hundred and forty-one patients with definite or classical rheumatoid arthritis were entered into an open randomized controlled trial with a flexible dose regimen designed to reflect clinical practice. Decisions to stop treatment with any one of the disease-modifying anti-rheumatic drugs (DMARDs) were based on an agreed trial protocol which defined criteria for adverse reactions and therapeutic failure. The managing physicians' decisions were confirmed in a separate monitor clinic. RESULTS: The proportion of patients who remained on their first DMARD or who were in remission at 5 yr was 53% for penicillamine, 34% for sodium aurothiomalate, 31%, for auranofin and 30% for hydroxychloroquine (P < 0.001). In patients who stayed on their first DMARD, all groups showed a 30-50% improvement in C-reactive protein, erythrocyte sedimentation rate, Ritchie Index and joint stiffness, and a deterioration in their Larsen score. There was no evidence of physician bias to explain the larger proportion of patients remaining on penicillamine for 5 yr. CONCLUSION: Despite the increased popularity of sulphasalazine and inmmunosuppressives, the drugs in this study continue to be used worldwide. The natural history of rheumatoid arthritis requires long-term follow up to establish drug efficacy. Evidence is needed as to whether the newer regimens will prove to be more effective and safer in the longer term than the commonly prescribed DMARDs. The data from this trial will provide a reference for comparison with future studies.  相似文献   
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