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991.
OBJECTIVE: To assess the long-term outcome of a cohort of 46 patients with idiopathic myositis by assessing both health status, as measured by the SF-36, and cumulative survival probability over a 20-yr follow-up period at a single rheumatology centre. Methods and results. Forty-six patients under long-term follow-up from 1978 to 1999 were identified from our database. All patients fulfilled three out of four of the Bohan and Peter criteria for myositis. We excluded those with malignancy-associated disease and those with inclusion body myositis. Twenty-three patients (50%) had adult-onset polymyositis, 14 (30.4%) had adult-onset dermatomyositis, one had childhood-onset dermatomyositis and eight (17.4%) had an overlap syndrome (associated with either systemic lupus erythematosus or rheumatoid arthritis). During the course of the disease, seven patients (15.2%) went into full remission, eight (17.4%) had monophasic illness, nine (19.6%) had a relapsing-remitting course, 16 (34.8%) had chronic progressive illness and six (13.04%) died. All patients had significantly lower SF-36 scores in all aspects of health compared with the general population (P< or =0.001). Patients with chronic progressive illness had significantly greater bodily pain (P< or =0.05, t-test) than those with a relapsing-remitting illness, but did not differ in other aspects of health. There was no significant difference in the scores in the different domains of the SF-36 between the patients with active disease and those with inactive disease (0.05相似文献   
992.
The authors investigated AIDS-related knowledge, high-risk behaviors, and relationships between AIDS-related knowledge, high-risk behaviors, and sociodemographic characteristics of 41 pregnant women entering treatment who were dependent on cocaine or opiates. At entry, patients completed self-report questionnaires on AIDS-related knowledge and sexual and drug use practices. There was a high rate of understanding of risk associated with drug use and perinatal transmission of HIV. Knowledge of high-risk sexual behavior varied, and knowledge of the medical consequences of HIV was modest. Engagement in several high-risk behaviors was identified: lack of condom use, intravenous drug use, sharing of needles, sex with an injecting drug user, and exchanging sex for money or drugs. AIDS-related knowledge and engagement in high-risk behaviors were not significantly correlated. Authors discussed implications of these findings for developing effective HIV prevention strategies in this population. (American Journal on Addictions 1996; 5:292–300)  相似文献   
993.
Interleukin 4 (IL-4) is a potent mediator of growth and differentiation for various lymphoid and myeloid cells. To isolate a cDNA encoding the murine IL-4 receptor, we have developed an expression cloning method that uses biotinylated ligand as a probe and that may be generally applicable to cloning of receptor genes. COS-7 cells transiently transfected with the cloned full-length cDNA bind murine IL-4 specifically with a Kd = 165 pM. Crosslinking of 125I-labeled IL-4 to COS-7 cells transfected with the cDNA reveals binding to proteins of 120-140 kDa. IL-4-responsive cells also express IL-4-binding proteins of 120-140 kDa but show additional bands at 60-70 kDa; the relationship of the smaller proteins to the larger ones is unclear. The nucleotide sequence indicates that the full-length cDNA encodes 810 amino acids including the signal sequence. While no consensus sequence for protein kinases is present in the cytoplasmic domain, a sequence comparison with the erythropoietin receptor, the IL-6 receptor, and the beta chain of the IL-2 receptor reveals a significant homology in the extracellular domain, indicating that the IL-4 receptor is a member of a cytokine receptor family.  相似文献   
994.
The clinical presentation of scleroderma in childhood is even more varied than in adult life. This study of 19 children shows that antinuclear antibodies (ANA) detected on the HEp2 cell substrate are just as common as in the adult disorders. All seven children with diffuse scleroderma or acrosclerosis were ANA positive, as were eight of the 12 with more localised disease. Antinucleolar antibodies were particularly frequent (58% overall), but anticentromere antibody was not observed. Enzyme-linked immunosorbent assays (ELISAs) for antibodies to collagen types I-V, in contrast to adult scleroderma, gave normal results in all childhood cases.  相似文献   
995.
To investigate the development of a reduced DLCO in patients with HIV-related disease, we studied 474 HIV-seropositive patients and performed serial lung function measurements over 18 months. The mean values of DLCO at presentation were lower in patients with more advanced HIV disease compared with asymptomatic HIV-seropositive patients (DLCO 88% of predicted). When compared with the DLCO in asymptomatic HIV-seropositive patients, the DLCO had reduced values in patients with persistent generalized lymphadenopathy (PGL) (82% of predicted, p less than 0.05), acquired deficiency syndrome-related complex (ARC) (73% predicted, p less than 0.001), nonpulmonary Kaposi's sarcoma (KS) (72% of predicted, p less than 0.001), nonpulmonary complications of AIDS excluding KS (73% of predicted, p less than 0.001), pulmonary KS (63% of predicted, p less than 0.001), pulmonary mycobacterial infection (68% of predicted, p less than 0.05), pyogenic infection (70%, p less than 0.05), acute Pneumocystis carinii pneumonia (PCP; 49%, p less than 0.001), and following recovery from PCP (71%, p less than 0.001). Serial lung function measurements over 18 months revealed no change in DLCO within any patient group, and in particular there was no tendency for a gradual decline. Clinical deterioration due to the development of PCP was associated with a reduction in DLCO. Conversely, in patients recovering from PCP, there was a partial improvement in DLCO over 3 months. Zidovudine (AZT) use did not affect DLCO within any diagnostic group or the recovery in DLCO following PCP. However, cigarette smoking was associated with further reductions in DLCO in all patient groups and with an impaired recovery of DLCO following acute PCP.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
996.
Missing natural teeth have been associated with a reduced acceptability for the taste and texture of hard foods as well as with an increase in the perceived difficulty of chewing these foods. The present study examined the role of the personality variables extroversion and anxiety in modulating the relationship between dentition status, masticatory performance, taste preference, texture preference, and perceived ease of chewing of an easy-to-chew food (pot roast) and a more difficult-to-chew food (raw carrots). Healthy adult men, participants in the Veterans Administration Dental Longitudinal Study, were examined. Results indicated that with increased age there was a tendency for texture acceptability to increase for the easy-to-chew food. Masticatory and swallowing performance were diminished in persons with artificial dentition, and these individuals also perceived an increase in the difficulty of chewing raw carrots. There was a significant association of anxiety, but not extroversion, with masticatory and swallowing performance.  相似文献   
997.
Comprehensive information about the independent value of different electrocardiographic (ECG) variables in predicting cardiac events after acute myocardial infarction (AMI) in the era of modern therapy is limited. Patients (n = 1,034) underwent standard electrocardiography from 5 to 7 days after an AMI. Several time intervals and PQRST abnormalities were analyzed from the electrocardiogram. During a mean +/- SD follow-up of 752 +/- 301 days on average, 42 patients (4%) experienced cardiac death, and 259 patients (25%) a cardiac death, nonfatal AMI, or unstable angina. Several ECG variables had a significant association with cardiac events in univariate comparisons. After adjustment for all risk variables in the Cox hazards model, lateral ST-segment depression (hazard ratio [HR] 4.76, 95% confidence interval [CI] 2.40 to 9.44, p <0.0001) and atrial abnormality with a terminal deflection of the P wave > or =0.1 mV deep and > or =40 ms in duration in lead V(1) (HR 2.46, 95% CI 1.25 to 4.82, p = 0.009) were the only ECG variables that independently predicted cardiac death. Lateral ST-segment depression also predicted the combined end point of cardiac death/nonfatal AMI/unstable angina in this model (HR 1.49, 95% CI 1.14 to 1.94, p = 0.003). In conclusion, lateral ST depression and atrial abnormality on the electrocardiogram are independent predictors of cardiac death after AMI. Lateral ST depression is also associated with ischemic cardiac events.  相似文献   
998.
The results of left ventricular endomyocardial biopsy by means of a long sheath technique in 154 patients are reported. The risks of left ventricular biopsy are those of left heart catheterisation. In 30 of these patients the results of left and right ventricular biopsy were compared, and in a further 10 patients the right ventricle only was biopsied. Biopsy from the left ventricle carries less risk of cardiac perforation, gives a higher incidence of successful biopsy, and with the exception of hypertrophic obstructive cardiomyopathy yields more diagnostic information.  相似文献   
999.
BACKGROUND: Previous studies designed to identify an association between body mass index (BMI) (calculated as weight in kilograms divided by the square of height in meters) and cardiovascular or total mortality in populations with known atherosclerotic disease have shown conflicting results. In this study, we used the Physicians' Health Study enrollment cohort to examine the risk of total and cardiovascular mortality among men reporting a history of myocardial infarction or stroke, excluding those who reported a history of cancer. METHODS: Cause-specific death was ascertained for 5010 men during a mean follow-up of 5.0 years. End points were classified as total deaths and deaths due to cardiovascular causes. Four BMI categories (<22.0, 22.0-24.9 [referent], 25.0-27.9, and > or =28.0) were created a priori. We used proportional hazards models to calculate age and multivariate-adjusted relative risks (RRs) for each BMI category for each end point. RESULTS: Compared with men with a BMI of 22.0 to 24.9, men with a BMI of 28.0 or greater had an age-adjusted RR of 1.11 (95% confidence interval [CI], 0.91-1.36), a multivariate RR of 1.04 (95% CI, 0.84-1.28) in a model that did not include biological mediators of obesity, and a multivariate RR of 1.06 (95% CI, 0.78-1.44) in a model that included these mediators. The RRs for cardiovascular mortality were similar, at 1.07 (95% CI, 0.85-1.35), 1.01 (95% CI, 0.79-1.29), and 1.01 (95% CI, 0.71-1.43), respectively. A BMI of less than 22.0 was associated with a small increased risk of total mortality and cardiovascular mortality. CONCLUSION: These findings indicate that elevated BMI may not be strongly associated with total or cardiovascular mortality among men with previously manifested coronary artery disease.  相似文献   
1000.
Recently, a vaccine consisting of DNA priming followed by boosting with modified vaccinia Ankara (MVA) has provided long-term protection of rhesus macaques against a virulent challenge with a chimera of simian and human immunodeficiency viruses. Here, we report studies on the development of the DNA component for a DNA/MVA HIV vaccine for humans. Specifically, we assess the ability of a codon-optimized Gag-expressing DNA and two noncodon-optimized Gag-Pol-Env-expressing DNAs to prime the MVA booster dose. The codon-optimized DNA expressed virus-like particles (VLPs), whereas one of the noncodon-optimized DNAs expressed VLPs and the other expressed aggregates of HIV proteins. The MVA boost expressed Gag-Pol and Env and produced VLPs. Immunogenicity studies in macaques used one intramuscular prime with 600 microg of DNA and two intramuscular boosts with 1 x 10(8) pfu of MVA at weeks 8 and 30. The codon-optimized and noncodon-optimized DNAs proved similar in their ability to prime anti-Gag T cell responses. The aggregate and VLP-expressing Gag-Pol-Env DNAs also showed no significant differences in their ability to prime anti-Env Ab responses. The second MVA booster dose did not increase the peak CD4 and CD8 T cell responses, but increased anti-Env Ab titers by 40- to 90-fold. MVA-only immunizations elicited 10-100 times lower frequencies of T cells and 2-4 lower titers of anti-Env Ab than the Gag-Pol-Env DNA/MVA immunizations. Based on the breadth of the T cell response and a trend toward higher titers of anti-Env Ab, we are moving forward with human trials of the noncodon-optimized VLP-expressing DNA.  相似文献   
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