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81.
Flow cytometry is a high-precision technique for rapid analysis and sorting of cells and particles. In theory, it can be used to measure any cell constituent, provided that a fluorescent tracer is available that reacts specifically and stoichiometrically with that constituent. The technique provides statistical accuracy, reproducibility, and sensitivity and allows simultaneous measurement of several constituents on a cell-to-cell basis. The main drawback of flow cytometry is the lack of visual control and structural information in solid tissues. Careful sample preparation, quality control of all staining and instrumentation procedures, and the use of immunohistologic or cytologic controls are essential for high-quality flow cytometric analysis. The technique has been used successfully for simultaneous measurement of DNA and tumor-associated antigens, oncogene products, proliferation markers, and markers for multidrug resistance in cultured cell lines and in cell suspensions prepared from solid tumors and cervical smears. Flow cytometry has the potential to play an important role in the study of carcinogenesis. With an appropriate panel of monoclonal antibodies, the technique can be used for screening, "biochemical" diagnosis of neoplasia, and rapid drug, hormone, and radiotherapy sensitivity tests.  相似文献   
82.
AIMS: To determine the availability of facilities for the investigation of hyperlipidaemia in the United Kingdom. METHODS: A questionnaire was sent to all health districts in the United Kingdom. RESULTS: The response rate was 81%. All laboratories used enzymatic techniques to measure serum triglyceride and cholesterol concentrations, although there were differences in standardisation procedures. Reference ranges for serum lipids were quoted by 58% of laboratories while 50% quoted "desirable limits". Almost half specified that fasting blood samples were required. High density lipoprotein cholesterol concentrations were estimated by 75% and apolipoproteins AI and B by 14% of laboratories; there were differences in specimen type and considerable diversity in procedures used for measurement. CONCLUSIONS: Many laboratories were unaware of current recommendations for screening for hypercholesterolaemia in the community. The present survey indicated an urgent need for the introduction of better reference methods, standardisation, and quality assurance procedures before apolipoproteins become a routine part of coronary heart disease risk assessment.  相似文献   
83.
BACKGROUND: There have been no previous studies on the role of inflammation in the brain for the second most common dementing disorder, dementia with Lewy bodies. OBJECTIVE: To investigate the degree of cortical inflammation in dementia with Lewy bodies (DLB) compared with Alzheimer disease (AD) and control brains. DESIGN AND MAIN OUTCOME MEASURES: Post-mortem tissue collection from a brain donor program using standardized diagnostic criteria. Brains collected from January 1, 1993, through December 31, 1996, were screened and selected only for the presence or absence of tau neuritic plaques. Results of immunohistochemistry for HLA-DR were quantified using area fraction counts. Counts were performed by investigators who were unaware of the diagnosis. Results were compared across groups using analysis of variance and posthoc testing. SETTING: A medical research institute in Sydney, Australia. PATIENTS: Eight brains with DLB and without the tau neuritic plaques typical of AD, 10 brains with AD and no Lewy bodies, and 11 nondemented controls without significant neuropathological features were selected from a consecutive sample. RESULTS: Compared with AD, DLB demonstrated significantly less inflammation in the form of HLA-DR-reactive microglia in all cortical regions (P<.001, posthoc). The level of inflammation in DLB was comparable to that seen in controls (P=.54, post hoc). CONCLUSIONS: Inflammation appears related to the tau neuritic plaques of AD. Despite similar clinical presentations, therapeutic anti-inflammatory strategies are not likely to be effective for pure DLB. Arch Neurol. 2000.  相似文献   
84.
PURPOSE: Invasive mucinous carcinoma of the ovary (mucinous epithelial ovarian cancer [mEOC]) is a histologic subgroup of epithelial ovarian cancer (EOC). Chemotherapy for mEOC is chosen according to guidelines established for EOC. The purpose of this study is to determine whether this is appropriate. PATIENTS AND METHODS: Women with advanced mEOC (International Federation of Gynecology and Obstetrics stage III or IV) who underwent first-line platinum-based chemotherapy were compared with women with other histologic subtypes of EOC in a case-controlled study. RESULTS: Eighty-one patients (27 cases, 54 controls) treated with platinum-based regimens were analyzed. The response rates for cases and controls were 26.3% (95% CI, 9.2% to 51.2%) and 64.9% (95% CI, 47.5% to 79.8%), respectively (P=.01). The odds ratio for complete or partial response to chemotherapy for mEOC was 0.19 (95% CI, 0.06 to 0.66; P=.009) compared with other histologic subtypes of EOC. Median progression-free survival was 5.7 months (95% CI, 1.9 to 9.6 months) versus 14.1 months (95% CI, 12.0 to 16.2 months; P<.001) and overall survival was 12.0 months (95% CI, 8.0 to 15.6 months) versus 36.7 months (95% CI, 25.2 to 48.2 months; P<.001) for cases and controls, respectively. The hazard ratio for progression and death was 2.94 (95% CI, 1.71 to 5.07; P<.001) and 3.08 (95% CI, 1.69 to 5.6; P<.001), respectively, for mEOC patients as compared with controls. CONCLUSION: Patients with advanced mEOC have a poorer response to platinum-based first-line chemotherapy compared with patients with other histologic subtypes of EOC, and their survival is worse. Specific alternative therapeutic approaches should be sought for this group of patients, perhaps involving fluorouracil-based chemotherapy.  相似文献   
85.
BACKGROUND: Trastuzumab provides significant clinical benefits in HER2-positive metastatic breast cancer patients when administered in combination with chemotherapy. Chemotherapy has also been shown to be beneficial in some patients with advanced non-small-cell lung cancer (NSCLC). The present randomized phase II trial examined the effect of adding trastuzumab to a standard chemotherapeutic combination (gemcitabine-cisplatin) in patients with HER2-positive NSCLC. PATIENTS AND METHODS: Patients with untreated stage IIIB/IV HER2-positive NSCLC received up to six 21-day cycles of gemcitabine 1250 mg/m(2) (days 1 and 8) and cisplatin 75 mg/m(2) (day 1). Patients in the trastuzumab arm received trastuzumab 4 mg/kg intravenously (i.v.) followed by 2 mg/kg/week i.v. until progression. RESULTS: Of 619 patients screened, 103 were eligible. Fifty-one patients were treated with trastuzumab plus gemcitabine-cisplatin and 50 with gemcitabine-cisplatin alone. Efficacy was similar in the trastuzumab and control arms: response rate 36% versus 41%; median time to progression 6.3 versus 7.2 months; and median progression-free survival (PFS) 6.1 versus 7 months. Response rate (83%) and median PFS (8.5 months) appeared relatively good in the six trastuzumab-treated patients with HER2 3+ or fluorescence in situ hybridization (FISH)-positive NSCLC. Addition of trastuzumab to gemcitabine-cisplatin was well tolerated, side-effects were as expected, and trastuzumab did not exacerbate the known toxicity of gemcitabine and cisplatin. Symptomatic cardiotoxicity was observed in one trastuzumab-treated patient. Serum trastuzumab concentrations in the presence of gemcitabine-cisplatin were comparable to those of trastuzumab alone. CONCLUSIONS: Trastuzumab plus gemcitabine-cisplatin is well tolerated. Clinical benefit was not observed. Although HER2 3+/FISH-positive patients may benefit from trastuzumab, the subgroup is too small to provide definitive information. No significant effect of gemcitabine-cisplatin on trastuzumab pharmacokinetics was observed.  相似文献   
86.
PURPOSE: The purpose of this research was to evaluate whether baseline health-related quality of life (HRQOL) parameters are prognostic factors for survival in locally advanced breast cancer patients. Although the literature highlights the important role of HRQOL parameters in predicting survival in advanced metastatic disease, little evidence exists for earlier stages. PATIENTS AND METHODS: The overall sample consisted of 448 patients randomly assigned to receive cyclophosphamide, epirubicin, and fluorouracil versus epirubicin, cyclophosphamide, and granulocyte colony-stimulating factor. Patients were enrolled in 12 countries. HRQOL baseline scores were assessed using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire C30. The Cox proportional hazards regression model was used for both univariate and multivariate analyses of survival. In addition, a bootstrap resampling technique was used to assess the stability of the outcomes. Bootstrap results were then applied for model averaging purposes as a means to account for the observed model selection uncertainty. RESULTS: The final multivariate model retained inflammatory breast cancer (T4d) as the only factor predicting overall survival (OS) with a hazard ratio of 1.375 (95% CI, 1.027 to 1.840; P =.03). The presence of inflammatory breast cancer lowers the median survival time from 6.6 to 4.2 years (36% reduction). None of the preselected HRQOL variables were prognostic for OS or disease-free survival, in either the univariate or multivariate analysis. CONCLUSION: Our findings suggest that baseline HRQOL parameters have no prognostic value in a nonmetastatic breast cancer population.  相似文献   
87.
PURPOSE: Cyclophosphamide, epirubicin, and fluorouracil (CEF), compared with classical cyclophosphamide, methotrexate, and fluorouracil (CMF) chemotherapy. has lead to an improvement in relapse-free and overall survival in premenopausal women with node-positive breast cancer. We undertook this analysis to more accurately define the estimate of risk of secondary acute leukemia (sAL) following epirubicin-containing chemotherapy regimens. PATIENTS AND METHODS: We assessed the conditional probability of sAL among 1,545 women who received adjuvant (n = 1,477) or neoadjuvant (n = 68) chemotherapy in four National Cancer Institute of Canada Clinical Trials Group trials from 1990 to 1999. The risks associated with epirubicin-containing regimens (CEF or epirubicin and cyclophosphamide [EC]) and other regimens (doxorubicin and cyclophosphamide [AC] or CMF) were determined. RESULTS: A total of 10 cases of sAL were observed (eight acute myelogeneous leukemia, two acute lymphoblastic leukemia): seven among women treated with CEF, two who had received AC, and one following CMF. Using competing risk statistics, the conditional probability of sAL was 1.7% (95% confidence interval [CI], 0.5 to 3.6) among 539 women treated with CEF chemotherapy at a follow-up of 8 years, 0.4% (95% CI, 0% to 1.3%) among the 678 who received CMF, and 1.3% (95% CI, 0% to 4.7%) among the 231 treated with AC. The conditional probability of death from breast cancer at 8 years for the entire group of women treated with epirubicin-containing regimens in all four trials was approximately 34.9%. CONCLUSION: CEF chemotherapy for breast cancer carries a small increased risk of sAL compared with CMF. These estimates of acute leukemia risk are important in discussing treatment with women, especially patients with a lower risk of death from breast cancer, such as those with node-negative breast cancer.  相似文献   
88.
BACKGROUND: Locally advanced and/or inflammatory breast cancer (LABC) is a heterogeneous disease. Molecular markers may help to understand this heterogeneity. This paper reports the results of a study assessing the potential prognostic or predictive value of HER-2, p53, cyclinD1, MIB1, ER and PgR expression by immunohistochemistry from patients included in an EORTC-NCIC-SAKK trial. PATIENTS AND METHODS: A total of 448 patients with a cytological or histological diagnosis of LABC were randomised into a trial comparing two anthracycline-based neoadjuvant regimens. Chemotherapy was followed by standard locoregional therapy. Survival was comparable in both arms. We collected and analysed centrally paraffin-embedded tumour specimens from 187 (72.5%) of 258 patients that had a histological diagnosis. RESULTS: Of the patients included in this molecular marker study 114 relapsed and 91 died. In the multivariate analysis p53 positivity was associated with a shorter progression-free survival [hazard ratio (HR) = 1.96; 95% CI 1.33-2.91; P = 0.0008) and a shorter overall survival (HR = 1.98; 95% CI 1.28-3.06; P = 0.002). PgR positivity predicted for a longer overall survival (HR = 0.54; 95% CI 0.35-0.83; P = 0.0045). CONCLUSIONS: p53 was an independent factor predicting for survival. In order to clarify whether p53 is a pure prognostic and/or a predictive factor, a phase III trial is being conducted (EORTC 10994/BIG 00-01 study) using functional assay in yeast from frozen tumour samples.  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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