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991.
Echocardiography has established an important role in the surveillance of patients with myocardial infarction. Segmental wall motion abnormalities are easily identified and their extension reflects the size of the infarct. Global left ventricular function may be assessed and left ventricular dilatation documented. This information is useful in evaluating the long-term prognosis. In addition, Doppler echocardiography is valuable for detecting complications persisting or occurring after the acute phase such as pericardial effusion, mural thrombus, aneurysm or mitral regurgitation. The indications of Doppler echocardiography should be guided by the symptomatology and the results of clinical examination.  相似文献   
992.
993.
Water processing rates of active suspension-feeding larvae of Culiseta morsitans and Culex quinquefasciatus 2nd and 4th instars were estimated through video image analysis of the conical jet flow driving the large recirculation patterns surrounding the organisms. In accordance with the principle of continuity, individual processing rates (PRs) were assessed by averaging a series of consecutive flow rates (Qx) defined as the product of the water velocity (Ux) and the associated cross-sectional area (Ax) along a transect passing through the center of the delineated jet flow. Results clearly show very tight adherence to the principle of continuity. They also demonstrate that, although extreme care must be taken when streamtube delineation is performed, the methodology used can generate reliable assessment of individual processing rates regardless of the instars or species studied. The small coefficient of variation observed in assessing PR at the larval level further underlines the consistency of the method. Significant differences in water processing rates were observed for different species and instars. These could partially be related to body size, head width, and the length of the lateral palatal brushes (LPBs), which are the structures involved in the production of the water jet. Assessment of the jet velocity at the feeding groove level suggests the key role of LPB beating frequency in the jet intensity, and consequently the magnitude of the processing rate. Analysis of data further indicates that obligate suspension feeders such as Cs. morsitans must sustain a larger flow pattern around the larvae to ensure sufficient particle entrapment than facultative suspension feeders (or even brushers) such as Cx. quinquefasciatus.  相似文献   
994.
We studied the course of adjuvant arthritis in rats by measuring clinical, biochemical, and histological parameters on day 36 after induction (representing the secondary reaction) and on day 171, which is at the stage of permanent deformity. The effect of SR 41319, a new diphosphonate, was evaluated on days 36 and 171, after three weeks of treatment (days 14-35 inclusive). In the absence of treatment all the measured parameters were markedly abnormal on day 36, indicating the presence of lesions that were still evolving. On day 171 clinical parameters and the lesion histological index remained the same, whereas the biochemical parameters and disease activity histological index had returned to normal, indicating that the lesions at this stage although severe were not inflammatory and consequently not progressing. SR 41319 treatment reduced the severity and progression of the disease both on day 36 and on day 171. We conclude that SR 41319 may be a potentially useful drug for the treatment of rheumatoid arthritis.  相似文献   
995.
Weanling diabetes-prone BB rats were fed AIN-76 diets containing high (HE, 1 g/kg diet), basal (NE, 0.2 g/kg) or low (LE, trace) vitamin E and were killed at 21, 42 or 60 days of age. Plasma and tissues (adrenals, pancreas, spleen, thymus, liver, brown and white adipose tissue, muscle and testes) were analysed for vitamin E. Vitamin E levels reflected the level in the diet and no diabetic animals were detected at these times. In a second experiment, a total of 90 diabetes-prone BB rats were kept on diets LE and HE for 6 months or until they became diabetic. 11/45 on LE and 5/45 on HE became diabetic. Again, plasma and tissue levels of vitamin E reflected the levels in the diet with the exception of the thymus of diabetic rats fed the high vitamin E diet. Thymus vitamin E levels (microgram/g tissue) were 1.8 and 1.2 in LE-fed diabetics and asymptomatic rats, respectively; and 22.7 and 49.5 in HE-fed diabetics and asymptomatic rats, respectively. The last 2 values were significantly different (p less than 0.005). There were no other differences in plasma or tissue levels of vitamin E in these groups of animals. These findings suggest that high dietary vitamin E may decrease the incidence of diabetes in animals which are able to accumulate sufficient amounts of the vitamin in the thymus. Since the thymus plays a key role in the maturation of T cell populations, which appear to be altered in this disease, it seems possible that the protective effect may be exerted at this level.  相似文献   
996.
997.
A patient presented with a ruptured azygos vein following esophagoscopy. The diagnosis was difficult. Selective angiography was helpful and surgical treatment ensured good result. This is the first case of this type to be reported in the literature.  相似文献   
998.
Variations in treatment of femoral neck fractures in Alberta.   总被引:1,自引:0,他引:1  
OBJECTIVES: To examine, in the province of Alberta, temporal trends, regional variations in treatment options and in-hospital death rates after a femoral neck fracture. DESIGN: A retrospective cohort study. PATIENTS: Six years' data were abstracted from the Alberta Morbidity File, the Alberta Health Stakeholder File and the Alberta Health Care Claims File. Patients were included if they were Alberta residents, aged 65 years or older, had sustained a femoral neck fracture and had undergone internal fixation, hemiarthroplasty or total hip arthroplasty. MAIN OUTCOME MEASURES: Death rates, arthroplasty rates and hospital stay. RESULTS: In-hospital death rates were similar across hospitals, with risks being higher for men, patients aged 80 years or older and those with more comorbid conditions. Arthroplasty rates varied from 58% to 77% among hospitals, and hospital stays associated with arthroplasty were significantly longer than those associated with internal fixation. The chance of undergoing arthroplasty varied from hospital to hospital by gender and by the number of comorbid conditions. CONCLUSION: Regional variations suggest lack of agreement among Alberta's surgeons as to how best to treat femoral neck fractures.  相似文献   
999.
1000.
Results of routine testing at other sites can supplement surveillance of the HIV epidemic in Australia which is largely basec upon voluntary testing. Since 1989, systematic onsite HIV testing has been undertaken on all bodies taken to the Victorian Institute of Forensic Medicine (VIFM). Information was collected on all cases of HIV infection detected at VIFM between 1989 and 1996, and matched to surveillance databases. In 8 years, 75 people were diagnosed with HIV; all except one were male. The age range was 14–70 years, mean 37.4 years. The major causes of death were suicide 35%, AIDS 21%, druc toxicity 16%, natural causes 12% and injury 7%. The major exposure categories were male homosexual 51%, male bisexual 11%, homosexual/bisexual IDU 16%, IDU other 8%, and haemophiliac 7%. For only two was exposure information unavailable. Seropositivity for anti-HCV and HBsAg was 37% and 11% respectively. The deceased was recorded as having HIV/AIDS on the police report in 73% of cases, and at least 90% of subjects had been diagnosed with HIV prior to their death. The study suggests there is relatively little undiagnosed HIV infection in Victoria, that HIV infection has not moved outside traditional risk groups, and that many tests for HIV are undertaken using false namecodes. Many patients could not be matched on the HIV/A|DS databases, identifying a problem with HIV surveillance systems in Victoria, and the need to capture all information on HIV positives detected at VIFM.  相似文献   
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