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BACKGROUND: Several examinations have detected a relation between depressive symptoms and medical utilization. However, selection biases have been involved in most previous examinations. We sought to test the association between depressive symptoms and prospective, increased medical care utilization, in a population-based Canadian sample, while controlling for utilization due to medical illness and controlling for selection bias. METHODS: Data from the Nova Scotia Health Survey 1995, an age- and sex-stratified random sampling of 3227 Nova Scotian adults, included the Center for Epidemiological Studies-Depression scale and items assessing chronic medical conditions and current limitations in daily activities resulting from medical illness. We linked survey data with medical care utilization measures for the year following the survey, including out-patient visits, reimbursement for out-patient services, hospitalizations, and hospitalization days. RESULTS: After controlling for age, sex, count of medical diagnoses and current medical severity, those with a greater level of depressive symptoms were at greater risk of having increased medical care utilization in the following year. These results remained after removing mental health care utilization costs. CONCLUSIONS: In a population-based sample, depressive symptoms predicted greater medical care utilization, independent of a number of medical severity measures. Whether depressive symptoms are a risk marker or a causal risk factor for increased medical utilization remains to be explored. 相似文献
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This study was designed to assess the serum and mucosal immune response to naturally acquired rotavirus enteritis in children. Serum and duodenal secretions were collected 1 week and again 4 to 5 weeks after the onset of illness from 10 children. In two of these children, the procedure was repeated 12 to 15 months later. Another 10 children with bacterial enteritis were studied as controls. The antibody response in serum included a significant elevation of rotavirus-specific immunoglobulin M (IgM) in acute-phase samples (P less than 0.05), but not in convalescent-phase samples, when compared with controls. Rotavirus-specific IgG and IgA levels were significantly elevated in convalescent-phase serum when compared with acute-phase serum (P less than 0.025), but not in control serum. Rotavirus-specific IgA levels in convalescent duodenal secretions were significantly raised when compared with both acute-phase and control samples (P less than 0.01). Rotavirus-specific IgM levels were elevated in acute-phase duodenal secretions (P less than 0.05), but not in convalescent-phase secretions. In two children, the secretory IgA response had disappeared by 12 months. These studies demonstrate the presence of rotavirus-specific antibody in duodenal secretions which may be important for protection against reinfection and may be capable of being stimulated by oral vaccination. 相似文献
87.
Effects of flanking base sequences on 5-bromodeoxyuridine mutagenesis in mammalian cells 总被引:2,自引:0,他引:2
The molecular mechanisms of incorporation-dependent, 5-bromodeoxyuridine (BrdU)-induced mutagenesis were analyzed in murine A9 cells that possess a single copy of theEscherchia coli gpt gene integrated into the chromosomal DNA as part of a shuttle vector. Four independently derived GPT– mutants with single base changes within the integratedgpt gene were utilized in BrdU-induced reversion analyses to test the relative mutability of guanine residues in four different settings: the 5 and 3 guanine residues of a GG doublet, the 3 guanine residue of a GGGG quartet, and the middle guanine residue of a GGG triplet. Two of the mutant lines possessed GG doublet sequences in which a GCAT transition at either guanine residue of the doublet leads to restoration of GPT enzyme activity without restoring wild-type DNA sequence. Both lines were shown to be effectively reverted by BrdU incorporation-dependent mutagenesis, and sequencing of thegpt genes from numerous independently derived revertants of both lines demonstrated that greater than 90% of the revertants arose due to GCAT transitions at the 3 guanine residue of the doublet. BrdU-induced reversion of two additional GPT– mutant lines demonstrated that the 3 guanine residue of a GGGG quartet is efficiently mutated, while the middle guanine residue of a GGG triplet sequence is at least 10-fold less mutable by BrdU incorporation-dependent mutagenesis than the 3 guanine residue of a GG doublet or GGGG quartet. All four mutant lines tested were equally revertible by treatment with the alkylating agent ethyl methane sulfonate. The results from this study define a sequence-specific mechanism for BrdU-induced, incorporation-dependent mutagenesis and demonstrate the use of reversion analysis for the determination of sequence specific effects at precise sites within a gene. 相似文献
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Autoimmune pancreatitis (AIP), a recently defined disease of unknown etiology, is characterized by inflammatory infiltrates in the pancreas with conspicuous involvement of the ducts. The disease clinically manifests in humans as epigastric pain, weight loss, and jaundice. This report describes the development of a novel animal model of this disease in the rat, which we have termed experimental autoimmune pancreatitis. Adoptive transfer of amylase-specific CD4(+) T cells was able to confer pancreatitis to naive syngeneic recipient animals. No treatments before the adoptive transfer of T cells were necessary for disease to ensue, and the severity of disease was proportional to the number of T cells administered. The pancreatic lesions of rats with experimental autoimmune pancreatitis were characterized histologically as overwhelmingly lymphocytic with occasional plasma cells, neutrophils, and mast cells. Acinar tissue destruction and ductular inflammation were common features, with less frequent involvement of larger ducts. Immunohistochemical analysis revealed the presence of CD4(+) T cells in large numbers as well as CD8(+) T cells, macrophages, and dendritic cells. Expression of MHC I and MHC II also increased at the site of the lesion. Clinically, the disease manifested as either failure to gain weight at a rate concomitant with control animals or as outright weight loss. Thus, administration of activated CD4(+) T cells specific for the pancreatic enzyme amylase can induce pancreatitis in the rat in a manner that is reminiscent of human AIP. 相似文献
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Tyrer P Thompson S Schmidt U Jones V Knapp M Davidson K Catalan J Airlie J Baxter S Byford S Byrne G Cameron S Caplan R Cooper S Ferguson B Freeman C Frost S Godley J Greenshields J Henderson J Holden N Keech P Kim L Logan K Manley C MacLeod A Murphy R Patience L Ramsay L De Munroz S Scott J Seivewright H Sivakumar K Tata P Thornton S Ukoumunne OC Wessely S 《Psychological medicine》2003,33(6):969-976
BACKGROUND: We carried out a large randomized trial of a brief form of cognitive therapy, manual-assisted cognitive behaviour therapy (MACT) versus treatment as usual (TAU) for deliberate self-harm. METHOD: Patients presenting with recurrent deliberate self-harm in five centres were randomized to either MACT or (TAU) and followed up over 1 year. MACT patients received a booklet based on cognitive behaviour therapy (CBT) principles and were offered up to five plus two booster sessions of CBT from a therapist in the first 3 months of the study. Ratings of parasuicide risk, anxiety, depression, social functioning and global function, positive and negative thinking, and quality of life were measured at baseline and after 6 and 12 months. RESULTS: Four hundred and eighty patients were randomized. Sixty per cent of the MACT group had both the booklet and CBT sessions. There were seven suicides, five in the TAU group. The main outcome measure, the proportion of those repeating deliberate self-harm in the 12 months of the study, showed no significant difference between those treated with MACT (39%) and treatment as usual (46%) (OR 0.78, 95% CI 0.53 to 1.14, P=0.20). CONCLUSION: Brief cognitive behaviour therapy is of limited efficacy in reducing self-harm repetition, but the findings taken in conjunctin with the economic evaluation (Byford et al. 2003) indicate superiority of MACT over TAU in terms of cost and effectiveness combined. 相似文献