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61.
62.
A total of 151 unselected malignant and nonmalignant lymphoid tissue samples were surveyed by Southern blotting for the presence of Epstein-Barr virus (EBV) DNA. Eight of 28 Hodgkin's disease (HD) samples (29%) had detectable EBV DNA. Both nodular sclerosis and mixed cellularity histologic results were positive. The tumor type with the next highest frequency, 8%, was diffuse large cell lymphoma. The presence of EBV DNA in some HD biopsies suggests that EBV may be a factor in the pathogenesis of this disease. Alternatively, its presence may be secondary to the immune deficiency characteristic of HD. The clonal B-lymphocyte expansions reported in some cases of HD may result from EBV infection.  相似文献   
63.
The present study further examined the in vitro response of human mononuclear cells (MNC) to theSarcocystis gigantea lectin (SGL). The results confirm our previous report that SGL is mitogenic for human MNC. We now report that SGL is not only a potent mitogen but also a polyclonal activator for human peripheral B cells. As was true for pokeweed mitogen (PWM, 2 g/ml), the addition of SGL (25 g protein/ml) to cultures of MNC caused lymphocyte proliferation and B-cell maturation, indicated by a marked increase in IgG and IgM production. As measured by the [3H]-thymidine incorporation assay, SGL induced significantly higher proliferative responses than PWM (P<0.01,n=24). The values obtained by SGL and PWM for IgG and IgM synthesis were essentially identical. As opposed to SGL, the sarcotoxin-containing fraction (SGTF) did not induce antibody formation or proliferative responses in human MNC.  相似文献   
64.
The persistence of Bordetella pertussis and B. parapertussis within vaccinated populations and the reemergence of associated disease highlight the need to better understand protective immunity. The present study examined host immunity to bordetellae and addressed potential concerns about the mouse model by using a comparative approach including the closely related mouse pathogen B. bronchiseptica. As previously observed with B. pertussis, all three organisms persisted throughout the respiratory tracts of B-cell-deficient mice, indicating that B cells are required for bacterial clearance. However, adoptively transferred antibodies rapidly cleared B. bronchiseptica but not human pathogens. These results obtained with the mouse model are consistent with human clinical observations, including the lack of correlation between antibody titers and protection, as well as the limited efficacy of intravenous immunoglobulin treatments against human disease. Together, this evidence suggests that the mouse model accurately reflects substantial differences between immunities to these organisms. Although both B. pertussis and B. parapertussis are more closely related to B. bronchiseptica than they are to each other, they share the ability to resist rapid clearance from the lower respiratory tract by adoptively transferred antibodies, an adaptation that correlates with their emergence as human pathogens that circulate within vaccinated populations.  相似文献   
65.
Between 1978 and 1984, we examined and performed arthroscopy on 1000 consecutive patients. Ninety-eight of the 1000 had isolated ACL damage. These cases do not include patients with initial ACL injuries combined with other intraarticular damage. Diagnosis was by physical and arthroscopic examination. Examination took place an average 13.6 months after injury. Of the 98 isolated ACL injuries, 56 were complete ruptures and 42 were partial ruptures. In most cases of partial rupture, the clinical diagnosis was wrong. "Meniscal damage" was the usual diagnosis in these cases; the true diagnosis was made only by arthroscopic examination. Thirty-four of the 98 patients with isolated ACL injuries (30 men and 4 women) developed further intraarticular damage. Of these 34, 20 had complete ACL rupture and 14 had partial ACL rupture. Treatment after primary injury included physiotherapy in all patients and bracing in those whose knee was unstable during daily activities. Reconstructive surgical procedures were not performed in those patients. The time lapse from the primary to the secondary injury varied from 1 month to 20 years, with an average of 28 months. The secondary damage was caused by a secondary injury that was mild (22 cases) or developed insidiously (12 cases). Five types of secondary damage were observed: partial ACL tears that became complete--11 cases; meniscal tear--8 cases; loosening and subluxation of the anterior horn of the medial meniscus--14 cases; and fracture or damage to the articular condylar cartilage, with or without bone involvement--11 cases. It should be emphasized that the secondary damages were at times combined.  相似文献   
66.
A prospective study of biochemical changes after vertical banded gastroplasty for morbid obesity, in 94 patients (10 males and 84 females, ages ranging from 18 to 59 years) has been carried out. Liver function tests and electrolyte estimations were performed preoperatively, during hospitalisation for surgery, at 6 weeks and at 6 months postoperatively, and demonstrated no significant changes in liver function in these patients 6 months after surgery. The study concludes that there is no increase in the risk of liver damage or electrolyte disturbance after vertical gastroplasty, but that there may be subtle hepatic changes present as gall bladder disease developed in 18 patients postoperation (19%).  相似文献   
67.
We compared the results of suprathreshold testing of the nasal periphery with those of quantitative assessment of the same area. One eye each from 81 patients in four categories (normal [21 subjects], low-risk ocular hypertensive [20 subjects], high-risk ocular hypertensive [20 subjects] and early glaucoma [20 subjects]) was tested with the nasal suprathreshold points of the Octopus G1 program and the Sargon peripheral field-nasal (PFN) program. Simple algorithms were developed to generate from the nasal suprathreshold points of the G1 program two "qualitative indices", mean defect-qualitative (MD-Q) and loss variance-qualitative (LV-Q); these are analogous to the indices mean defect and loss variance respectively, which were calculated from the PFN program data. MD-Q and LV-Q were found to be well correlated with their quantitative counterparts. They provide a uniform method for interpreting the nasal suprathreshold points of the G1 program and help identify patients in whom further quantitative testing is likely to yield useful information.  相似文献   
68.
P M Marzuk  K Tardiff  A C Leon  M Stajic  E B Morgan  J J Mann 《JAMA》1990,263(2):250-256
We determined the prevalence of recent cocaine and alcohol use among motor vehicle fatalities occurring in New York, NY, from 1984 through 1987. Recent cocaine use was detected at autopsy in 18.2% of the sample and no significant difference between drivers (20.0%) and passengers (13.9%) was found. Both alcohol and cocaine metabolites were found in 10.0% of cases tested. The prevalence of cocaine metabolites or alcohol detected in driver fatalities aged 16 through 45 years did not change significantly when the period prior to the widespread availability of "crack" cocaine (1984 through 1985) was compared with the period immediately following the introduction of crack cocaine (1986 through 1987). Additional studies are needed both to elucidate the association between cocaine use and these fatalities and to determine the value of screening persons seriously injured in traffic accidents in areas where such drug use is endemic.  相似文献   
69.
The study evaluated a multifaceted educational intervention systematically designed to increase physician involvement in cholesterol-lowering practices. We hypothesized that knowledge, perceptions and behaviours would be enhanced in participating physicians, compared with controls. Method: Fifty-one family physicians were assigned randomly to three groups; the two experimental groups attended a training workshop, received physician and patient education materials and ongoing consultant support. One experimental group also received a “cuing” intervention. The control group received no interventions. Outcome measures included knowledge and attitude scores, self-efficacy perceptions, and physician dietary counselling behaviour. Measures were taken at pretest, 6 weeks and 15 months later. Results: Intervention group physicians achieved significantly higher knowledge scores than the control group at the six-week test; the differences disappeared at 15 months. Attitudes, self-reported practices and overall self-efficacy scores were similar across groups. Within group variation was highly significant. Physician dietary counselling scores were significantly higher in the intervention groups (p = 0.0001). Some associations were seen among knowledge, attitude, self-efficacy and dietary counselling scores. Conclusion: Physician behaviour change in cholesterol reduction may not depend entirely upon knowledge, attitudes and perceptions. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
70.
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