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71.
Human herpesvirus 8 (HHV-8) DNA sequences were examined in peripheral blood mononuclear cell (PBMC) DNA samples of 56 children, 15 healthy adults, and 10 renal transplant patients by the polymerase chain reaction (PCR). The PCR amplification was carried out using the published KS330(233) primer pairs to amplify HHV-8 DNA sequences. The PCR-amplified products were confirmed by Southern blot hybridization with radiolabeled 233 bp HHV-8 DNA fragment, which was cloned and sequenced from the PCR-amplified product of Kaposi's sarcoma tissue. Six PCR-amplified product of four children and two renal transplant patients were cloned and sequenced. HHV-8 DNA sequences were detected in 36 of 56 (64%) normal children, in 12 of 15 (80%) healthy adults, and in all 10 renal transplant patients by Southern blot hybridization of PCR-amplified products. Six PCR-amplified products were confirmed by sequencing. These results suggest that HHV-8 infection is prevalent in the Japanese population with infection occurring in early childhood.  相似文献   
72.
The ribonucleoprotein (RNP) enzyme telomerase is required for replication of eukaryotic chromosomal termini. The RNA moiety of telomerase is essential for enzyme function and provides the template for telomeric DNA synthesis. However, the roles of its nontemplate domains have not been explored. Here we demonstrate that a novel interspecies telomerase RNA swap in vivo creates a functional but aberrant telomerase. Telomerase RNA from the ciliate Glaucoma chattoni was expressed in Tetrahymena thermophila cells. The telomerase RNAs from these two species have almost superimposable secondary structures. The template region base sequence is identical in the two RNAs, but elsewhere their sequences differ by 49%. This hybrid telomerase RNP was enzymatically active but added only short stretches of telomeric repeat tracts in vivo and in vitro. This new enzyme also had a strong, aberrant DNA cleavage activity in vitro. Thus, molecular interactions in the RNP involving nontemplate RNA domains affect specific aspects of telomerase enzyme function, raising the possibility that they may regulate telomerase activity.  相似文献   
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Recent developments in video camera technology, new instruments, and advanced surgical techniques have increased the importance of video-assisted thoracoscopic surgery (VATS). Currently, VATS offers a new approach in the diagnosis and treatment of many thoracic conditions previously treated only by standard thoracotomy. In our experience, VATS is a safe, reliable, and effective alternative to thoracic surgery. With further improvements and refinements in video imaging and endoscopic instruments, more procedures will be technically feasible. The long-term results of VATS compared to open thoracotomy will require extensive follow up and prospective trials to determine its true value.  相似文献   
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OBJECTIVE: The role of a deficiency of vitamin B1 in the development of alcoholic complaints is confined to the case of the Wernicke-Korsakov syndrome. Findings concerning a deficiency of thiamine in alcoholics in comparison with normal persons are contradictory and there are no differentiated tests in the case of delirium tremens. In this study the vitamin B1 absorption in patients with delirium tremens was of interest in connection with the presence or absence of hallucinations and autonomic symptoms. METHOD: Male patients (N = 70) with delirium tremens were compared with a group of 13 controls. The controls and patients were hospitalized in order to ensure abstinence from alcohol. The examination of the delirium patients was carried out with their consent after termination of the delirium tremens and again on discontinuance of drug therapy. In the case of 33 delirium patients the absorption of thiamine was tested again 4 weeks after the first examination. RESULTS: The absorption of vitamin B1 was in general only minimally lower in the case of the delirium patients in comparison with the nonalcoholics. The results showed, however, a considerably greater range of scattering of vitamin B1 absorption in the delirium patients. The absorption conditions showed marked improvement in the 4 weeks after delirium. The extent of absorption of vitamin B1 showed no influence on the duration of delirium. The patients with visual hallucinations, however, showed lower thiamine absorption than patients without such symptoms, whereas no dependence of autonomic symptoms on vitamin B1 absorption was seen. CONCLUSIONS: The disturbed absorption conditions in the delirium patients were obvious at the time of the examination as demonstrated by the wide range of absorption values. Improvement or near normal conditions were registered 4 weeks after the delirium. The absorption conditions had possibly already improved during the few days of alcohol abstinence in the course of the delirium treatment. The reduced vitamin B1 absorption of patients suffering from visual hallucination corresponds to observations of alcoholic hallucinosis.  相似文献   
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The purpose of this study was to examine differences in the way Britain and the United States invest in and deploy a new medical technology. We used structured interviews to obtain information on the technical sophistication and approximate replacement value of all hospital-based obstetrical ultrasound machines in every maternity hospital in Washington state and Wales. The supply of hospital-based ultrasound machines--approximately two machines per 1,000 births--was similar in both countries. Wales had fewer advanced ultrasound machines than Washington state, and they were based exclusively in high-volume district general hospitals; there were no obstetric ultrasound machines in the private sector. In Washington state, the majority of advanced machines were in small and medium-sized hospitals, and many private offices had ultrasound machines. The approximate replacement value of hospital-based machines was three times as high per birth in Washington state as in Wales. In the case of obstetrical ultrasound, centralization of facilities, a relatively small private sector, and global budgeting lead to lower expenditures per patient within the National Health Service without compromising access to care.  相似文献   
79.
Dot-immunoblotting assay (DIA) using five monoclonal antibodies (MAbs) to infectious bronchitis virus (IBV) was used to detect and classify the viruses propagated in embryonated chicken eggs. Using a group-specific MAb 3F5, 10 reference strains and 12 Korean isolates of IBV were successfully detected by DIA, and the lowest virus titer of IBV detected by DIA was approximately less than 10(3.8) mean embryo infective dose/ml. For evaluating the diagnostic efficiency, DIA was compared with the conventional infectious bronchitis (IB) diagnostic method. IBV antigens in allantoic fluid from embryonated eggs inoculated with IB-suspected field samples were specifically detected by DIA within only one or two egg passages, whereas the conventional embryonated egg inoculation method required four to seven egg passages for confirming IBV infection. These results indicated that DIA could significantly reduce time and cost for IB diagnosis. For examining the possibility of classifying IBV by DIA, four strain-specific MAbs, 3A4, 2A3, 6F7, and 2C6, were used. According to the MAb reacting patterns to the IBV antigens, the 10 IBV reference strains were classified into six groups; seven strains belonged to three different groups, and the other three strains each belonged to an individual group. In the case of 12 Korean isolates of IBV, they were classified in six groups. Among the six groups, the MAb reacting patterns of three groups matched those of the IBV reference strains, but the others did not. These data suggest that at least three variant serotypes of IBV exist in Korea.  相似文献   
80.
BACKGROUND: Cost-effectiveness analysis, Helicobacter pylori research and the development of proton pump inhibitors are having an increasing impact on the management of dyspepsia. However, clinical trials have not always included both H. pylori diagnosis and proton pump inhibitors in their protocols. METHODS: Patients who were referred for upper gastrointestinal endoscopy by their general practitioner were randomized to either prompt endoscopy followed by directed medical treatment (conventional group, n=38), or to empirical treatment with omeprazole and, in the case of symptom relapse, serological screening for H. pylori infection followed by eradication therapy in seropositive patients (empirical group, n=42). The study lasted for up to 1 year. RESULTS: In the empirical group, only 13 patients (31%) underwent endoscopy. The average number of days for which the patients kept records of their dyspeptic symptoms was 266 (95% CI: 226-307) in the empirical group, of which 166 (95% CI: 128-204) were symptom-free. In the conventional group, 159 (95% CI: 119-198) out of 255 days (95% CI: 209-302) were recorded as symptom-free. The average medical cost in the empirical group was $284 (95% CI: 218-350) and in the conventional group $491 (95% CI: 383-600). In the empirical group, two malignancies were found, whereas in the conventional group one malignancy was found. CONCLUSIONS: The empirical drug treatment strategy in patients with persistent dyspeptic symptoms resulted in 69% fewer diagnostic endoscopies with lower medical costs and equal effectiveness in the first year, compared to prompt endoscopy followed by directed medical treatment.  相似文献   
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