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31.
AF Jorm H Christensen AS Henderson PA Jacomb AE Korten A Mackinnon 《Age and ageing》1996,25(2):126-129
Formal assessment of cognitive decline with cognitive tests can be difficult, requiring either two measurement points or a comparison of 'hold' with 'don't hold' tests. Informant-based assessment provides an alternative approach because informants can adopt a longitudinal perspective and directly rate cognitive change. A study was carried out to assess the validity of informant ratings collected by means of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). A community sample of 500 subjects aged 74 or over underwent four cognitive tests on two occasions 3½ years apart. On the second occasion, informants filled out the IQCODE. Subjects rated as having moderate or severe decline were found to have greater change on the cognitive tests. These findings support the validity of informant ratings of cognitive decline. 相似文献
32.
Lymphokine-induced phagocytosis in angiocentric immunoproliferative lesions (AIL) and malignant lymphoma arising in AIL 总被引:1,自引:1,他引:1
A factor that augmented the phagocytosis of IgG-coated ox red blood cells by the human monocyte/macrophage line U937 was identified in cell culture supernatants from two of two patients with angiocentric peripheral T cell lymphomas, three of three patients with angiocentric immunoproliferative lesions that were not frankly malignant, and one of two patients with T lymphoblastic malignancies. The factor was not present in supernatants derived from 14 nonangiocentric peripheral T cell lymphomas of other histologic types nor in ten cases of B cell lymphoma and two cases of Hodgkin's disease. A similar factor was present in the supernatants of concanavalin A (Con A)-stimulated normal peripheral blood mononuclear cells and in the supernatants of IL-2- dependent T cell lines derived from normal peripheral blood. The factor had an apparent mol wt of greater than 50,000 daltons, was heat labile (100 degrees C for two minutes), and stable at pH 2.0. Its stimulation of phagocytosis was independent of any increase in number of Fc receptors. Thus, this factor is probably not gamma-interferon. This factor may play a pathogenetic role in the hemophagocytic syndromes associated with certain T cell malignancies and immunodeficient states. 相似文献
33.
In vivo expression of the B7 costimulatory molecule by subsets of antigen-presenting cells and the malignant cells of Hodgkin's disease 总被引:10,自引:0,他引:10
Munro JM; Freedman AS; Aster JC; Gribben JG; Lee NC; Rhynhart KK; Banchereau J; Nadler LM 《Blood》1994,83(3):793-798
The B-lymphocyte/accessory-cell activation antigen B7 (BB1) has been shown in vitro to stimulate T-lymphocyte proliferation and cytokine production via CD28 present on the latter cells. In this study, benign lymphoid tissues, lymphomas, and extralymphoid inflammatory sites were examined immunohistochemically using anti-B7 and other relevant monoclonal antibodies. B7 was expressed by benign transformed germinal center B cells, as it was by B cells of follicular lymphomas. B7 was also expressed by a subpopulation (a mean of 31% to 65%) of macrophages and dendritic cells in a variety of lymphoid tissues. It was present in abundance on all macrophages constituting sarcoid granulomas in lymph nodes. In extralymphoid inflammation, 17% to 35% of macrophages expressed B7 only weakly. Cases of Hodgkin's disease showed expression of B7 by the majority of Reed-Sternberg cells or malignant mononuclear variants, a phenomenon that potentially contributes to the lymphocytic accumulation that is a feature of this condition. CD28+ T cells were seen in all areas where T cells were present. B7+ and CD28+ cells colocalized in, for example, lymphoid follicles, lymph node paracortex, sarcoid granulomas, and Hodgkin's disease tissue, indicating a potential for cellular interaction via these molecules at these sites. 相似文献
34.
O'Day SJ; Rabinowe SN; Neuberg D; Freedman AS; Soiffer RJ; Spector NA; Robertson MJ; Anderson K; Whelan M; Pesek K 《Blood》1994,83(9):2707-2714
Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) clearly hastens myeloid recovery in patients with relapsed hematologic malignancies undergoing autologous bone marrow transplantation (ABMT). In efforts to further improve neutrophil engraftment and shorten hospital stay in ABMT patients, rhGM-CSF was administered by a potentially more potent route (continuous infusion) to non-Hodgkin's lymphoma (NHL) patients with better BM reserve (first remission). Time to myeloid engraftment was compared with that of NHL patients treated in first remission at our institution on a similar ABMT protocol but without growth factor support (controls). Median neutrophil engraftment (absolute neutrophil count, 500 cells/microL) in first remission patients treated with rhGM-CSF was 14 days, compared with 22 days in controls (P = .0001). Hospital stays were also significantly reduced for rhGM-CSF patients (P = .0003). Platelet engraftment did not differ between the two groups. Persistent fever and generalized serositis were the primary toxicities. rhGM-CSF, delivered by this route, was efficacious but more toxic than 2-hour rhGM-CSF infusions previously reported by other investigators. Future alterations in both dose and schedule may retain comparable efficacy yet diminish toxicity. 相似文献
35.
Pauwels R Calverley P Buist AS Rennard S Fukuchi Y Stahl E Löfdahl CG 《Respiratory medicine》2004,98(2):99-107
Efforts to assess the efficacy of new therapies in the treatment of acute exacerbations of chronic obstructive pulmonary disease (COPD) have been hampered by the lack of a widely agreed and consistently used definition. A variety of definitions have been used in clinical studies, based on changes in patient symptoms or the requirement for antibiotic therapy, oral steroids or hospitalisation. To date, none of these definitions have been assessed in detail for their reliability, responsiveness and validity determined. Considerable heterogeneity in the aetiology and manifestation of COPD exacerbations makes identification and quantification of defining symptoms extremely difficult. New approaches are therefore being sought with a view to identifying a serum or tissue marker that can be used as a valuable diagnostic tool. Improvements in data recording will also contribute to the accuracy of data retrieval and assessment. If we are to progress to a level of sophistication seen in the diagnosis and management of other diseases, it is evident that considerable research efforts will be required to improve our understanding of COPD exacerbations and develop a standard definition for these events, thereby facilitating the assessment of therapeutic approaches. 相似文献
36.
Metabolic myopathies: evaluation by graded exercise testing 总被引:3,自引:0,他引:3
Exertional muscle pain and fatigue are common complaints; some patients with these symptoms have a metabolic myopathy. We have performed graded exercise testing with analysis of expired ventilation on 13 individuals with various kinds of metabolic myopathies. Their results differed from normal and reflected the underlying biochemical abnormality. Patients with disorders of the mitochondrial electron transport chain demonstrated marked limitations in aerobic metabolism and a greatly reduced maximum oxygen consumption. During intense exertion, normal individuals increase carbon dioxide generation due to buffering of lactic acid. This did not occur in patients with McArdle disease, in whom the respiratory exchange ratio (carbon dioxide production/oxygen consumption) did not rise above 1.0 at maximum exercise. These results indicated a deficit in anaerobic metabolism. Pyruvate dehydrogenase complex allows pyruvate produced from carbohydrate metabolism to enter the citric acid cycle. Patients with this enzyme deficiency showed an initially normal pattern followed by an abrupt cessation in carbohydrate dependent aerobic metabolism at higher work loads. During high-intensity exercise, progressive anaerobic metabolism was not accompanied by additional oxygen consumption. Finally, results from a patient with carnitine palmitoyl transferase deficiency revealed an early dependence on carbohydrate metabolism. The ventilatory threshold occurred at a low percentage of maximal oxygen consumption, reflecting the limited availability of lipid substrates for aerobic metabolism. Detection of some muscle metabolic abnormalities can be made on small biopsy specimens. However, definitive diagnosis of the defect nearly always requires studies on fresh or frozen muscle tissue obtained by an open biopsy. The decision on how the tissue should be processed and which metabolic studies should be performed frequently needs to be made before the biopsy is obtained. Thus, a noninvasive method to initially characterize patients with potential metabolic disorders is useful. Exercise testing with expired gas analysis can indicate the presence of a metabolic myopathy and results can then be used to direct the appropriate biochemical evaluations. 相似文献
37.
Markson LE Vollmer WM Fitterman L O'Connor E Narayanan S Berger M Buist AS 《Archives of internal medicine》2001,161(3):379-384
BACKGROUND: Measures of patient satisfaction or dissatisfaction with treatment are increasingly being used as indicators of quality of care. As these measures become more widely used, it is important to know if patient dissatisfaction is associated with important processes or outcomes of medical care. METHODS: Survey of patient-reported asthma management issues using the Asthma Therapy Assessment Questionnaire in a large health maintenance organization in the Pacific Northwest. Associations between patient dissatisfaction with asthma treatment and patient-reported measures of asthma control, patient-provider communication, and belief in asthma medications (self-efficacy) were examined. RESULTS: Of the 5181 adult members with asthma enrolled in the health maintenance organization, 30% indicated dissatisfaction with current treatment. Dissatisfaction was higher among patients with a higher number of asthma control problems, patient-provider communication problems, or belief in medication problems (eg, failure to believe their medications are useful and inability to take asthma medications as directed). The odds of dissatisfaction with treatment were 2.8 (95% confidence interval [CI], 2.4-3.3; P<.001) for asthma control problems, 2.0 (95% CI, 1.6-2.6; P<.001) for communication problems, and 8.0 (95% CI, 6.7-9.5; P<.001) for belief in medication problems compared with patients without these perceived problems. CONCLUSION: Patient dissatisfaction with treatment may be related to important asthma disease management issues. 相似文献
38.
STUDY QUESTION: What is the prevalence of respiratory symptoms and obstructive pulmonary disease by age, sex, and smoking history in a population aged 70 years and older? What is the association between selected comorbidities and obstructive pulmonary disease? PATIENTS AND METHODS: A questionnaire on respiratory symptoms and disease, selected comorbidities, and smoking history was mailed to a cross-sectional, sex- and age-stratified, random sample of the population 70 years and older of Bergen, Norway. RESULTS: About 11% of these elderly persons reported having at least one current obstructive pulmonary disease, 8% reported daily wheezing, and 12% reported significant dyspnea. The only respiratory symptom or disorder to show any clear age-related pattern was dyspnea, which increased through age 89 before declining. Dyspnea, current asthma, and current chronic bronchitis were about half as likely in males as females, after adjusting for smoking pack-years. Persons with obstructive pulmonary disease reported problems with walking, heart disease, and muscle/joint disease more frequently than those without. CONCLUSIONS: The prevalence of respiratory symptoms and obstructive pulmonary disease has been estimated. Only dyspnea was associated with age in this elderly population. Female sex was a predictor of dyspnea, current asthma, and current chronic bronchitis. 相似文献
39.
Efficacy of bupropion for relapse prevention in smokers with and without a past history of major depression 下载免费PDF全文
Cox LS Patten CA Niaura RS Decker PA Rigotti N Sachs DP Buist AS Hurt RD 《Journal of general internal medicine》2004,19(8):828-834
BACKGROUND: This study evaluated the efficacy of bupropion for relapse prevention in smokers with and without a past history of major depressive disorder. Changes in depressive symptoms were also examined. DESIGN: Data were gathered prospectively from a randomized, double-blind relapse prevention trial of bupropion conducted at five study sites. A total of 784 smokers (54% female, 97% white) were enrolled. Using the Structured Clinical Interview for Depression, 17% of the subjects reported a past history of major depressive disorder at baseline. All subjects received open-label bupropion SR (300 mg/d) for 7 weeks. Subjects abstinent from smoking at the end of 7 weeks (N = 429) were randomized to bupropion SR (300 mg/d) or placebo for the remainder of the year and followed for 1 year off medication. The primary outcome measures were median time to relapse to smoking and the 7-day point-prevalence smoking abstinence rate. Self-reported abstinence from smoking was verified by expired air carbon monoxide. The Beck Depression Inventory was used to assess depressive symptoms at baseline and at weeks 8 and 12. RESULTS: Median time to relapse did not differ by past history of major depressive disorder. Bupropion was associated with higher point-prevalence smoking abstinence at the end of medication compared to placebo (P = .007), independent of a past history of major depressive disorder. Moreover, change in depressive symptoms during the double-blind phase did not differ for those with and without a past history of major depressive disorder. CONCLUSIONS: Extended use of bupropion for relapse prevention is effective for smokers with and without a history of major depression. 相似文献
40.
Relative impact of smoking and reduced pulmonary function on peptic ulcer risk. A prospective study of Japanese men in Hawaii 总被引:1,自引:0,他引:1
The aim of this study was to determine whether reduced pulmonary function is an independent risk factor for peptic ulcer. Among 5933 Japanese men studied in Hawaii, 243 developed gastric ulcers and 99 developed duodenal ulcers 20 yr after an examination completed in 1968. The examination included measurement of forced expiratory volume in 1 s and a detailed smoking history. The percent predicted forced expiratory volume was significantly and inversely related to ulcer incidence, but not after adjustment for smoking or among those who had never smoked. Cigarettes were associated with increased ulcer risk in both stomach and duodenum but showed a dose-response in pack years only for gastric ulcer. We conclude that the association of reduced pulmonary function with peptic ulcer in the Japanese in Hawaii is largely attributable to smoking and that smoking is more strongly related to gastric than duodenal ulcer. The especially strong link between cigarettes and gastric ulcer suggests that decreased smoking or synchronous decrease in cigarette tar content may have contributed to the recent unexplained decrease in male gastric ulcer. 相似文献