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991.
OBJECTIVE: To determine the views of elderly persons with physical limitations about a number of aspects of the end stage of life and termination of life. DESIGN: Enquiry. SETTING: University of Groningen, the Netherlands. METHOD: An enquiry was conducted in 1995 among 575 elderly (429 females, 146 males; age 57-99 years; 281 living alone) with physical restrictions (mostly heart disease, hypertension, rheumatism or other articular diseases). The group had been selected from the 'Groningen longitudinal aging study'. The respondents were asked (a) what they thought about euthanasia, (b) whether they worried about the end stage of life, (c) whether they were afraid of death and how much they were 'preoccupied with death'. For the last-mentioned two questions a visual analogue scale was used. RESULTS: Almost one-third of the elderly were not preoccupied with death and over half were not afraid of death. Very few scored high on these scales. Respondents' views about the acceptability of active termination of life varied greatly: almost half were of the opinion that their life had to be terminated once they themselves had developed complete dementia. Regarding the end stage of life, respondents mostly worried about being a burden to others, being completely dependent on others, having to say goodbye to their loved ones and having to suffer greatly. Elderly persons with poorer health were more preoccupied with death and worried more about the problems of the end stage of life. CONCLUSION: Most of those interviewed were not greatly preoccupied with or afraid of death. They did worry, however, about the problems that might be associated with the end stage of life.  相似文献   
992.
BACKGROUND: To determine the best cutoff values of aspartate aminotransferase (AST) and alanine amino-transferase (ALT) in detecting viral hepatitis C infection among patients of continuous ambulatory peritoneal dialysis (CAPD). METHODS: 90 (44 male and 46 female) CAPD patients and 526 adult controls (266 male, 260 female) were enrolled. Serum AST and ALT were measured by an auto-analyser monthly. Serum HBsAg was examined using a RIA method and anti-HCV by an second-generation EIA method. The best cutoff values of AST and ALT for detecting viral hepatitis were obtained from the ROC (receiver-operating characteristic) curve. RESULTS: The prevalence of anti-HCV(+) was significantly higher in CAPD patients (16.7%) than in normal controls (4.9%), while that of HBsAg(+) was similar in both groups. CAPD patients had significantly lower levels of serum aminotransferases compared to normal controls. Mean AST were 23.8 IU/l in normal control and 18.8 IU/l in the CAPD patients (P < 0.001). Mean ALT were 21.9 IU/l in normal controls and 15.3 IU/l in the CAPD patients (P < 0.001). CAPD patients with HCV infection had higher serum AST and ALT levels than those without. However, HBV infection did not cause significant serum aminotransferase elevation in patients. The conventional cutoff values of AST (40 IU/l) and ALT (40 IU/l) for detecting viral hepatitis yielded only a sensitivity of 27.3 and 18.2% respectively; on the contrary, our revised cutoff values of AST (24 IU/l) and ALT (17 IU/l) had better sensitivities (AST, 72.7%; ALT, 63.6%). For serial aminotransferase values, the sensitivity of AST and ALT for detecting HCV were 36.4 and 27.3% by conventional criteria, and were both 81.8%, by our newly revised criteria. CONCLUSIONS: Serum aminotransferase cutoff values should be modified for screening viral hepatitis in a CAPD population. Our new cutoff criteria had important clinical implications in providing benefits of earlier detection and possible prevention from chronic hepatic deteriorations.  相似文献   
993.
The specific binding of antibodies to the V3 loop in sera from human immunodeficiency type 1 (HIV-1)-infected individuals was investigated. Different V3 structures were analyzed as full-length loops or by pepscan. Our data show that on full-length V3 loops, both variable regions on either side of the tip of the loop (GPGRAF) contribute to a common epitope for type-specific antibodies. Type-specific antibodies bound strongly and at high titers to native V3 loops but negligibly once the loop was denatured. In contrast to the type-specific, discontinuous epitope, the linear, conserved epitopes presented by the full-length V3 loop, the tip, the amino-terminal base, and the carboxy-terminal base were not accessible to serum antibody. When the V3 sequences were analyzed with linear peptides, antibodies bound preferentially to peptides containing the conserved GPGRAF sequence. Thus, two different specificities of V3-directed antibodies were detected in patient sera. Unlike group-specific antibodies directed against GPGRAF peptides, lack of type-specific antibodies directed against the discontinuous epitope was correlated with viral escape from autologous neutralization. Our data suggest that the full-length conformation of the V3 loop is accessible predominantly to highly type-specific antibodies present in sera from HIV-1-infected individuals. These antibodies are directed against discontinuous V3 epitopes, not against conserved linear V3 targets. The implications of these findings for viral escape and blockade of infection with V3-based vaccines are discussed.  相似文献   
994.
Dermatofibrosarcoma protuberans (DFSP) with fibrosarcoma (FS)-like areas (DFSP-FS) is a peculiar neoplasm that combines microscopic findings of DFSP and FS. Because of the scarce number of cases published, tumor prognosis remains controversial. The clinical histories and the histologic material of 27 cases of DFSP were reviewed. Four of them showed fibrosarcomatous areas. Follow-up data, ranging from 12 to 125 months, were obtained in all four cases. Two patients had repeated local recurrences. One patient developed pulmonary metastases and died of disease 49 months after diagnosis. In the other two patients, no recurrences or metastases were detected at 12 and 70 months after local excision, respectively. Progressive increase of FS areas, cellular density, cellular atypia, and mitotic activity were observed during the recurrences. All cases showed diffuse positive immunostaining for CD34 in DFSP areas. Three cases were also CD34-positive in FS areas. Based on a careful review of the literature and our personal experience, we conclude that DFSP-FS is a rare variant of DFSP with a higher rate of local recurrences and more distant metastases than typical DFSP.  相似文献   
995.
Bruxism is a parafunction observed both in young and adult populations. The mean prevalence is about 20% and is decreasing with age. Women appear to clench more frequently than men. Often, bruxism is understood as both clenching with occasional tooth contact or grinding. A correct and validated definition has only recently been suggested. Many symptoms are assigned to this process, although few symptoms scientifically can be used as specific diagnostic criteria. The symptoms most often associated with bruxism like muscle-stiffness and -pain, limitation of mouth opening. TMJ-internal derangements, toothwear, are also found in TMD-patients. Because the bruxism-process is not only a problem for the patient, who suffers from pain, dysfunction and possible toothwear, it concerns also the dentist. It is essential that those who treat the bruxist-patient, have an understanding of the etiology, diagnosis and management of bruxism, of the many described oral parafunctional behaviors (oromotor behavior). This literature-review could not find a causal etiological mechanism between the occurrence of TMD-symptoms and the bruxism although a relationship between those two conditions has been described.  相似文献   
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A growing body of evidence indicates that cyclin-dependent kinases (CDKs) regulate the activity of eukaryotic origins of replication both positively and negatively. Although the details of this control remain unclear, recent work suggests that CDKs act directly at origins, where they associate with and phosphorylate several key initiator proteins. These data suggest that a CDK-regulated replication switch operates at each origin to ensure that initiation occurs precisely once per cell cycle.  相似文献   
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