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31.
J W Clark  M A Tucker  M H Greene 《Cancer》1987,60(4):864-869
Three sisters developed non-Hodgkin's lymphoma (NHL). Thirteen maternal relatives had adenocarcinomas of various types, predominantly breast and large bowel. Detailed laboratory assessment of this family revealed a variety of immunologic abnormalities. Two lymphoma patients had elevated anti-early antigens (EA) Epstein-Barr virus (EBV) titers. One of the two also had a markedly elevated anti-viral capsid antigen (VCA) EBV titer. The two lymphoma patients were human leukocyte antigen (HLA)-identical, but two unaffected siblings shared the same HLA haplotypes. One of the lymphoma patients and four unaffected family members were anergic; and three unaffected family members had a decreased percentage of T-cells. These data suggest that a subtle disturbance in cellular immune functions may play a causal role in some familial aggregations of malignant lymphoma.  相似文献   
32.
OBJECTIVE: The objective of this retrospective cohort study was to determine whether coronary artery bypass graft (CABG) surgery is effective and cost-effective relative to medical management of coronary artery disease (CAD) in the elderly. SUMMARY BACKGROUND DATA: The aging of the U.S population and the improvements in surgical techniques have resulted in increasing numbers of elderly patients who undergo this surgery. The three randomized, controlled trials (RCTs) that established the efficacy of CABG surgery completed patient enrollment from 19 to 24 years ago excluded patients older than 65 years. Although information regarding outcomes of CABG in this population is mainly available in case series, a major lacuna exists with respect to information on quality of life and cost effectiveness of surgery as compared with medical management. METHODS: The authors retrospectively formed surgical and medically managed cohorts of octogenarians with significant multivessel CAD. More than 600 medical records of patients older than 80 years who underwent angiography at our institution were reviewed to identify 48 patients who were considered reasonable surgical candidates but had not undergone surgery. This cohort was compared with 176 patients who underwent surgery. RESULTS: The cost per quality-adjusted life year saved was $10,424. At 3 years, survival in the surgical group was 80% as compared with 64% in the entire medical cohort and 50% in a smaller subset of the medical cohort. Quality of life in patients who underwent surgery was measurably better than that of the medical cohort with utility index scores, as measured by the EuroQoL, (a seven-item quality of life questionnaire) of 0.84, 0.61, and 0.74, respectively. CONCLUSIONS: Performing CABG surgery in octogenarians is highly cost-effective. The quality of life of the elderly who elect to undergo CABG surgery is greater than that of their cohorts and equal to that of an average 55-year-old person in the general population.  相似文献   
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We studied the detectability of mineralized and non-mineralized simulated pulmonary nodules with dual energy digital radiography. "Soft tissue" and "bone" images (pixel size = 0.2 mm, 10 bits deep) were obtained with subtraction image processing after a single simultaneous exposure (100 kVp, 8 mAs, 17 mR skin exposure dose) of two storage phosphors with an interleaved 0.9 mm copper wafer. Three classes of paraffin-based nodules (0.5 to 3.0 cm) of varying mineral concentration (0, 120 and 190 mg/cm3 K2HPO4) were randomly positioned on the chest wall of two healthy volunteers to simulate calcified and non-calcified nodules. The average receiver operating characteristics (ROC) area of six readers (n = 2880 observations) showed that digital "bone" images (ROC area: 0.77 +/- 0.03) were significantly better (P less than 0.04) than conventional radiographs (OC Film, Lanex medium screens, 141 kVp, 19 mR skin exposure dose) (ROC area: 0.71 +/- 0.05) in detecting calcification in nodules. The unsubtracted digital images of lower kilovoltage were not superior to the 141 kVp conventional radiographs in a subgroup of two readers (ROC area: 0.73 +/- 0.02). Digital "soft tissue" images were equivalent to conventional chest radiographs in detecting soft tissue pulmonary nodules (ROC areas: 0.92 +/- 0.04 and 0.92 +/- 0.05, respectively.  相似文献   
35.
The purpose of this study was to determine the effectiveness of a semirigid orthosis in restricting ankle inversion-eversion range of motion (ROM), and evaluate its effect on subjects' ability to produce muscular torque, during pre- and post-exercise test conditions. Thirty healthy subjects, 15 males and 15 females, with no history of right ankle injury were evaluated. Active ankle inversion-eversion torque and angular displacement were measured on a LIDO(R) isokinetic system, with the subjects' right ankle positioned in 0 degrees of plantarflexion. T-tests for paired samples at the 0.001 confidence level revealed that the orthosis demonstrated significant inversion-eversion range restrictive capabilities; did not interfere with maximum inversion-eversion torque production; and retained its support effectiveness following 20 minutes of dynamic exercise. The results suggest that the tested orthosis may be an effective prophylactic in preventing ankle sprains and beneficial to individuals with chronic ligamentous instability. J Orthop Sports Phys Ther 1989;11(6):245-252.  相似文献   
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37.
Clustering of cardiovascular risk factors is thought to occur early in life. The endothelium is an important regulator of microvascular function. We investigated the relationship between microvascular function and cardiovascular risk factors in 145 normal, healthy children aged 11-14 years. Skin microvascular responses, measured using laser Doppler imaging, to iontophoresis of acetylcholine (ACh) and sodium nitroprusside (SNP), were negatively correlated with percentage body fat ( r =−0.20, P < 0.05 and r =−0.18, P < 0.05, respectively). Subjects were stratified into quintiles based on 2-h, post-feeding glucose levels. Subjects in the upper glucose quintile (range 7.4-11.4 mmol l−1) showed significantly lower vasodilatation to both ACh (   P < 0.005  ) and SNP (   P < 0.02  ) than those in the lower quintile (range 3.9-4.9 mmol l−1). Waist-to-hip ratio and the fasting insulin resistance index were significantly greater in subjects in the upper quintile than those in the lower quintile ( P < 0.001 and P < 0.05, respectively). Additionally, in subjects in the upper glucose quintile, fasting triglyceride correlated with fasting insulin ( r = 0.59, P < 0.001) and with the fasting insulin resistance index ( r = 0.49, P < 0.009), and plasma levels of cholesterol and 2-h glucose were also correlated ( r = 0.40, P < 0.05). In a cross-section of normal children, microvascular function was negatively associated with adiposity. Additionally, in a subgroup of subjects, there was a clustering of high post-feeding glucose, impaired microvascular function, increased insulin resistance and higher central fat distribution. These findings suggest that risk factors for adult cardiovascular disease begin to cluster in normal children, which might have important consequences for development of atherosclerosis later in life.  相似文献   
38.
A comprehensive family practice clerkship program at Howard University College of Medicine has been conducted since 1970. This institution is one of three predominantly black institutions offering a family practice program. The senior clerkship is mandatory and at least 20 to 25 percent of each class elect to participate in a four-to six- week family practice preceptorship. As a result of the clerkship''s success, over 50 percent of the program''s graduates actively practice in primary medical manpower shortage or medically underserved areas.  相似文献   
39.
Immunoblots were used to study the immunoglobulin G response to Borrelia burgdorferi in experimentally and naturally exposed dogs. Adsorption studies confirmed that the antibodies were specific for B. burgdorferi. Experimentally exposed dogs were asymptomatic. Naturally exposed dogs included both asymptomatic animals and animals showing signs compatible with Lyme disease. Naturally exposed dogs were from four geographic regions of the country. No differences were detected between immunoblot patterns of naturally exposed symptomatic or asymptomatic dogs from different areas of the country. The immunoblot patterns obtained with sera from experimentally exposed dogs were different from those obtained with sera from naturally exposed dogs and were characterized by reactivity to fewer and different protein bands. Immunoblot analysis using an OspA-protein-producing Escherichia coli recombinant showed that experimentally exposed dogs produced antibodies to OspA, whereas naturally exposed dogs did not. Modifications of the immune response over time, different routes of antigen presentation, and strain variation are factors postulated to account for the observed differences.  相似文献   
40.
An immunohistochemical method for the detection of progesterone receptors (PgR) using the monoclonal anti-PgR antibody KD 68 was utilized to study paraffin-embedded tissue sections from women with endometrial carcinoma and hyperplasia. Stromal as well as myometrial nuclear PgR were nearly always apparent. In carcinoma, 11/24 (46%) of cases showed epithelial positivity, whereas in hyperplasia 8/9 (89%) were PgR-positive (P less than 0.05). Initial biochemical PgR assays by the dextran-coated charcoal method were compared with results of PgR-immunocytochemical assays (ICA) in the paraffin-embedded tissue and were in concordance in 92%. In the one discordant specimen, PgR-ICA-negative tumor cells were seen infiltrating PgR-ICA-positive myometrium, and the biochemical assay was thus felt to be falsely positive. Twelve additional cases of endometrial carcinoma were also studied for estrogen receptor (ER) by immunocytochemistry. Two were positive for both ER and PgR, while five were negative for both receptors. The immunocytochemical methods described allow for analysis of routinely fixed, paraffin-embedded specimens, thus permitting analysis of very small specimens and archival material.  相似文献   
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