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81.
AIMS: To determine the prevalence of Epstein-Barr virus genome in primary cerebral lymphomas occurring in the absence of immune suppression. METHODS: Forty eight consecutive patients with lymphomas restricted to the central nervous system were identified, all of whom had had neurosurgical biopsies performed at the National Hospitals for Neurology and Neurosurgery, London. Only five patients had some form of underlying immune deficiency; 43 were apparently normal. The tumours were studied with immunohistochemical markers and by in situ hybridisation, using a biotinylated probe to the internal repeat region of Epstein-Barr virus. RESULTS: All the lymphomas were B cell in origin. Tumours from the five immunosuppressed patients all showed hybridisation, as did two of the "spontaneous" tumours. CONCLUSIONS: This is the largest series of cerebral lymphomas so far probed for Epstein-Barr virus genome: as more are examined, it is suggested that a small proportion of the tumours from immunocompetent patients will also contain the virus.  相似文献   
82.
To assess the role of noninvasive tests--quantitative photoplethysmography, air plethysmography, and quantitative duplex scanning, we compared a group of normal (group N, eight limbs) volunteers to patients with severe chronic venous insufficiency who were stratified according to the degree of reflux seen on the current "gold standard," descending phlebography. Group M (10 limbs) had mild (grades 0 to 2) reflux, and group S (10 limbs) had severe (grades 3 to 4) reflux as determined by phlebography. Quantitative photoplethysmography could identify normal from abnormal limbs but could not distinguish the severity of reflux. Air plethysmography was used to calculate venous filling index, ejection fraction, and residual volume fraction. Ejection fraction was the same in all groups. Venous filling index could not significantly distinguish the degree of reflux (group M vs group S) but increased as reflux increased. Residual volume fraction was considerably higher in group S. Quantitative duplex valve closure time was measured in the superficial femoral and popliteal veins, with the values added together in each limb to give a total valve closure time (TVCT). A TVCT value greater than or equal to 4 seconds correlated best with severe phlebographic reflux, with a sensitivity of 90%, a specificity of 94%, and an accuracy of 93%. This value was confirmed as the best test for venous reflux by receiver operating characteristic curve analysis. Thus in the evaluation of patients with severe chronic venous insufficiency who are candidates for phlebography and surgery, quantitative duplex measurement of TVCT gives the best noninvasive assessment of the severity of deep venous reflux.  相似文献   
83.
Hordenine (N, N-dimethyltyramine) was found previously in the title plant. The detection of tyramine, N-methyltyramine, and choline and the crystallization of candicine (N, N, N-trimethyltyramine chloride) is now reported for this species.  相似文献   
84.
Human services organizations often are coalitions of many elements in the community. They have vague goals, intangible output, and the "needle" of professionalism all to make the operating manager's job a difficult and challenging one. The manager can control, however--if he understands some of the particular problems and characteristics of organizations in this industry.  相似文献   
85.
The book reviewed in this article discusses the use of brief interventions in the treatment of adolescent substance abuse. Topics covered include the developmental context within which adolescent substance use occurs, the use of the harm reduction approach to reduce substance use, current assessment instruments, and the role of cognitive and genetic factors in the etiology of substance abuse. Examples of specific brief interventions with adolescents are described and possible avenues for future transdisciplinary research are explored. This expansive sourcebook will be of value to clinicians and academicians alike.  相似文献   
86.
PURPOSE: Denileukin diftitox is a fusion protein combining diphtheria toxin and interleukin-2 (IL-2) that targets tumor cells expressing the IL-2 receptor. Its efficacy has been shown in CD25+ cutaneous T-cell lymphoma, but not in B-cell non-Hodgkin's lymphoma (NHL). A phase II study was performed to evaluate the efficacy and tolerability of denileukin diftitox for relapsed or refractory B-cell NHL. PATIENTS AND METHODS: Patients with relapsed or refractory B-cell NHL were eligible. Tumor CD25 expression was determined by immunohistochemistry or flow cytometry. Denileukin diftitox was administered intravenously at a dose of 18 microg/kg once daily for 5 days every 3 weeks, up to eight cycles. RESULTS: Of the 45 patients assessable for response, 32 (71%) were refractory to the last chemotherapy treatment, and all were previously treated with rituximab. Three complete responses (6.7%) and eight partial responses (17.8%) were observed, for an overall response rate of 24.5%. Nine patients (20%) had stable disease. Objective response rates were similar in CD25+ (22%) and CD25- histologies (29%), as were stable disease rates (22% and 18%, respectively). For responding patients, the median time to treatment failure was 7 months, with a median follow-up in survivors of 18 months (range, 9 to 28 months), and the projected progression-free survival at 20 months was 24% (95% CI, 0% to 60%). Most toxicities were low-grade and transient. CONCLUSION: Denileukin diftitox seems to be effective in relapsed or refractory, CD25+ and CD25- B-cell NHL and is well-tolerated at the dosage evaluated. Evaluation of denileukin diftitox in combination with other agents may be warranted.  相似文献   
87.
PURPOSE: We evaluated the prognostic significance of indium-111 (111In)-capromab pendetide imaging for patients with prostate cancer who underwent salvage radiotherapy (RT) for recurrent disease after prostatectomy. PATIENTS AND METHODS: Records were reviewed for all men who underwent 111In-capromab pendetide imaging at a single institution from February 1997 through December 1999. We identified 30 eligible men who were radiographically negative for metastatic disease, who had increasing serum prostate-specific antigen (PSA) after primary radical prostatectomy, and who received salvage RT. Clinical interpretations of indium monoclonal antibody (In-mab) scan results were compared with postsalvage RT PSA response. RESULTS: Using an American Society of Therapeutic Radiation and Oncology definition of PSA failure, in men with a positive scan in at least one location (n = 14), the cumulative 2-year PSA control after salvage RT was 0.38 +/- 0.13 (+/- SE) compared with 0.31 +/- 0.13 for men with a normal antibody scan in and outside the prostate fossa (n = 15; proportional hazard ratio [PHR] = 1.32; 95% confidence interval [CI], 0.52 to 3.36). For men with a positive antibody scan limited to the prostate fossa (n = 9), PSA control at 2 years was 0.13 +/- 0.12 (PHR 1.77; 95% CI, 0.65 to 4.85). The 2-year probability of PSA control after salvage RT for men with positive scan results outside the prostate bed irrespective of In-mab findings in the prostate fossa (n = 5) was 0.60 +/- 0.22 (PHR 0.81; 95% CI, 0.17 to 3.78). CONCLUSION: In contrast to previous reports, for patients with postprostatectomy biochemical relapse who received salvage RT, presalvage RT In-mab scan findings outside the prostate fossa were not predictive of biochemical control after RT.  相似文献   
88.
The purpose of this study was to compare self-reports of colorectal cancer (CRC) screening by fecal occult blood test (FOBT), sigmoidoscopy, and colonoscopy with medical records in a multiprovider health care setting. Relatives of CRC patients residing in Ontario, Canada completed a questionnaire indicating whether or not they had ever had any CRC screening tests. Medical records from physician's offices and hospitals were compared with the self reports, and where possible, reasons were obtained for nonmatching reports. Medical records for colonoscopies were readily available from various sources, and self-reports of this procedure were very accurate (kappa statistic for agreement beyond chance = 0.87). For sigmoidoscopy and FOBT, the agreement was poorer (kappa = 0.29 and 0.32, respectively); however, there were difficulties in obtaining records for these two procedures. Sigmoidoscopy procedures that took place many years ago were difficult to document, and physician's offices were unable to provide FOBT reports in many cases. Self-reports of colonoscopy were very accurate in this population, whereas self-reports of sigmoidoscopy and FOBT are somewhat less accurate, although this is likely due to challenges in obtaining a confirmatory record rather than an overreporting of tests. In a multiprovider publicly insured health care setting such as Canada, using self-reported information is likely to provide sufficiently accurate information for colonoscopy, but for other CRC screening tests, there may be difficulty in obtaining true estimates of the frequencies of these procedures.  相似文献   
89.
90.
Formal retrospective case review and sudden infant death   总被引:2,自引:0,他引:2  
A review of 24 consecutive sudden infant deaths was undertaken to evaluate the importance of the various stages in the postmortem assessment of such cases. Death in three cases was caused by obvious trauma. Of the remainder, 16 were attributed to sudden infant death syndrome (SIDS), 4 to accidental asphyxia (identified by death scene examination and/or formal case review) and 1 to a lingual thyroglossal duct cyst. Three (14%) of 21 deaths thought to be SIDS after postmortem examination were attributed to asphyxia following subsequent formal case review.  相似文献   
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