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11.
The role of selected prior medical conditions in the etiology of hematopoietic malignancies was examined in a case-control study of members of two regional branches of the Kaiser Permanente Medical Care Program (USA). Past history of chronic infectious, autoimmune, allergic, and musculoskeletal disorders was abstracted from medical records for leukemia (n = 299), non-Hodgkin's lymphoma (NHL, n = 100), and multiple myeloma (n = 175) cases and matched controls (n = 787). Little difference was found between cases and controls for most of the chronic conditions evaluated, including sinusitis, carbuncles, urinary tract infections, pelvic infections, herpes zoster, asthma, rheumatoid arthritis, psoriasis, bursitis, and gout. Only three statistically significant elevated risks were found, i.e., with combined disc disease myeloma among patients with prior eczema and disk and other musculoskeletal conditions, and NHL following tuberculosis. Only two of these associations showed consistent patterns by sex and geographic region (myeloma with eczema and with musculoskeletal conditions). While prior history of eczema and musculoskeletal conditions may slightly increase risk of myeloma, this study provided little if any support for an association of chronic infectious, autoimmune, allergic, and musculoskeletal conditions with subsequent occurrence of the leukemias or NHL. Additionally, these data did not support a role for chronic antigenic stimulation, as defined in previous epidemiologic studies, in the etiology of hematopoietic malignancies.Ms Doody and Drs Linet, Pottern, Boice, and Fraumeni are with the Epidemiology and Biostatistics Program, National Cancer Institute. Dr Glass is with the Kaiser Permanente Medical Care Program, Northwest Region, Portland, Oregon, USA. Dr Friedman is with the Kaiser Permanente Medical Care Program, Northern California Region, Oakland, California, USA. Address correspondence to Ms Doody, Radiation Epidemiology Branch, National Cancer Institute, Executive Plaza North, Room 408, Bethesda, MD 20892, USA. This research was supported in part by National Cancer Institute contracts NO1-CP-01047, NO1-CP-01054, NO1-CP-11009, NO1-CP-11037, NO1-CP-31035, and NO1-CP-61006.  相似文献   
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Cerebral blood flow and glucose utilization were measured in rat neocortex, hippocampus and striatum following methylenedioxymethamphetamine injection (5 mg/kg, i.v.), using the tracers [14C]iodoantipyrine and [14C]2-deoxyglucose, respectively. In control rats, blood flow was coupled to glucose metabolism, but in methylenedioxymethamphetamine-treated rats, marked hyperperfusion was measured in frontal and parietal cortex with no change in glucose use. This suggests that methylenedioxymethamphetamine has the potential to disrupt cerebrovascular control.  相似文献   
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A multiplex polymerase chain reaction (PCR) procedure was adapted for the rapid and efficient evaluation of deletions of the hypoxanthine guanine phosphoribosyltransferase (hprt) gene in human T-lymphocytes. The hprt clonal assay was used to isolate in vivo-arising hprt-deficient T-cells from six healthy males. Mutant frequencies ranged from 9-27 × 10?6. Simple crude cellular extracts from 223 mutants were analyzed for hprt gene deletion. Sixteen (7.2%) were found to be due to total gene deletion and 22 (9.9%) were due to partial gene deletion. The relatively high frequency of total gene deletions was caused by replicate isolates of a single mutational event as shown by single-strand conformation polymorphism (SSCP) analysis of rearranged T-cell receptor (TCR)-γ genes. Eighteen of the 22 partial hprt gene deletion mutants were determined to be of independent origin based on a unique hprt mutation or SSCP-TCR-γ pattern. One-half (9/18) of the partial deletion mutants involved all or part of exon 4 alone, suggesting that this region of the hprt gene is prone to deletion. The small deletions effecting exon 1 (1 mutant), exon 2 (2 mutants), and exon 4 (6 mutants) would not have been detected by conventional Southern blot analysis and may represent a new, previously unrecognized class of mutations. The ready isolation of such intragenic deletions will allow the characterization of breakpoint junctions and may provide insights into the important processes of DNA breakage and rejoining. © 1994 Wiley-Liss, Inc.  相似文献   
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The aim of this study was to determine the relationship between serum magnesium and TNF-alpha levels in obese subjects. A cross-sectional population based study that included 192 non-diabetic, non-hypertensive subjects allocated in three categories of body mass index (BMI) <25; > or =25 to <30 kg/m2; and > or =30 kg/m2. Elevation of TNF-alpha levels was defined by serum levels > or =3.5 pg/mL, and low serum magnesium by levels < or = 0.74 mmol/L. Multivariate odds ratios (OR) adjusted by age, HOMA-IR index, and glucose tolerance status are presented. Obese subjects exhibited higher serum concentration of TNF-alpha (p = 0.002) and lower serum magnesium levels (p < 0.0001) than lean and overweight subjects. Ninety-one (47.4%) subjects showed elevated levels of TNF-alpha, of them 7 (10.9%), 31 (48.4%), and 43 (67.2%) in the groups with BMI <25, > or = 25 to < 0, and > or =0 kg/m2, respectively. Multivariate OR between low serum magnesium and TNF-alpha levels in obese subjects was of 1.8, Cl95% 1.2-9.1, P = 0.001, whereas in the lean and overweight individuals of 1.1, Cl95% 0.7-8.7, P = 0.12, and 1.3, Cl95% 0.9-10.8, P = 0.09, respectively. These data shows that low serum magnesium levels and elevated TNF-alpha are related in the obese subjects. It will be necessary to conduct more studies in order to add new data on this issue.  相似文献   
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To enhance individual and family health during recovery from heart surgery, this study employed nursing interventions based on self-efficacy and family stress theory during the hospitalization period and for 3 months thereafter. The effectiveness of the interventions were assessed through a randomized trial in which 67 prospective bypass and valve surgery patients, aged 30-77 years, and their spouses, were allocated either the experimental interventions or usual care and followed for 6 months. At 3 months post-surgery, the only statistically significant differences between the experimentals and controls were on perceived self-efficacy for lifting and tolerating emotional distress. At 6 months no significant differences were found on individual or family measures. Analyses revealed that age, gender and preoperative cardiac status significantly affected individual recovery. The study is continuing with a larger sample in order to explicate the recovery process and to better determine whether a low intensity nursing intervention can effect changes in individual and family recovery.  相似文献   
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