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71.
When first introduced, the advanced breast biopsy instrumentation (ABBI®) system seemed to have many advantages as a diagnostic procedure. Problems have arisen, however, both in terms of patient unsuitability and mechanical failure. In addition, there has been uncertainty as to whether the complete lesion removal it afforded could be considered definitive treatment in malignant cases. Incision margins were looked at to investigate that possibility. Of the 183 patients we saw in our first year of experience with ABBI, 48 (26%) were rejected for being poor candidates for it. In the remaining 132 biopsies there were 31 (23%) technical difficulties. All told, 14 malignancies were discovered, all of which appeared to have pathology-free incision margins radiologically. However, 13 of these 14 (93%) proved on pathologic examination to have residual malignancy. ▪  相似文献   
72.
Dow L  Phelps L  Fowler L  Waters K  Coggon D  Holgate ST 《Thorax》1999,54(12):1104-1106
BACKGROUND: Studies in children and young women have indicated an increased risk of respiratory illness in association with the use of domestic gas appliances, possibly caused by oxides of nitrogen generated when gas is burned. It is not known whether risks are similarly increased in older subjects. METHODS: A questionnaire about respiratory symptoms in the past year and potential risk factors for respiratory disease was mailed to 6000 men and women aged 65 years and older who were selected at random from the lists of general practices in North Bristol, UK. Associations between symptoms and the use of gas appliances were examined by logistic regression with adjustment for age, sex, social class, and smoking habits. RESULTS: Questionnaires were completed by 4792 (80%) of those mailed. The most common symptoms were exercise induced breathlessness, wheeze, or chest tightness (51%); wheeze (27%); morning phlegm (20%); and daytime breathlessness at rest (19%). In an analysis that included all subjects only weak associations were found with use of gas appliances, odds ratios all being 1.2 or less. The risks associated with use of a gas hob tended to be higher in women, with odds ratios of 1.36 (95% CI 1.01 to 1.83) for wheeze and 1.33 (95% CI 0.56 to 3.17) for morning chest tightness, but were lower than had been reported previously in younger women. CONCLUSION: The absence of stronger associations cannot readily be explained by bias or confounding. Gas cookers and fires are unlikely to be an important cause of respiratory illness in the elderly. If they do cause such illness, the largest risks are likely to be in women who use gas hobs.  相似文献   
73.
PURPOSE: To determine whether ciliary neurotrophic factor (CNTF) or brain-derived neurotrophic factor (BDNF) treatment leads to long-term photoreceptor survival in hereditary retinal degeneration. METHODS: An autosomal dominant feline model of rod-cone dystrophy was used throughout the study with two normal animals. In the first experiment, intravitreal injections of a human CNTF analogue (Axokine; Regeneron Pharmaceuticals, Tarrytown, NY) were administered to one eye of each animal (n = 10) beginning on postnatal day 10 and were repeated every 4 weeks. Clinical and histopathologic examinations were performed at 5.5, 9.5, and 13.5 weeks. In the second experiment, animals (n = 17) were randomly assigned to receive intravitreal injections of either Axokine (at half the initial dose), human BDNF, or the vehicle for Axokine to one eye at 5.5 weeks. The same therapy was repeated every 4 weeks in each group. Clinical and histopathologic examinations were performed at 9.5, 13.5, and 17.5 weeks. Photoreceptor survival was assessed by cell counting. Apoptotic cells were identified by morphology and a modified TdT-dUTP terminal nick-end labeling (TUNEL) technique. In the third experiment, two normal animals were treated with Axokine as in the first experiment. Glial fibrillary acidic protein ((GFAP) immunohistochemistry was performed to assess glial cell reaction. RESULTS: In the first two experiments, Axokine significantly prolonged photoreceptor survival (P < 0.01) and reduced the presence of apoptotic cells (P < 0.05) and TUNEL-positive cells (P < 0.05). In the second experiment, results in the the BDNF- and sham-injected eyes were not significantly different from those in the untreated eyes. Minimal posterior subcapsular cataract and mild retinal folds were found in all Axokine-treated eyes in both dystrophic and normal animals. These complications were milder in the second experiment when injections were started later and at a reduced dose. GFAP immunolabeling was also increased in all Axokine-treated eyes. CONCLUSIONS: Axokine, but not BDNF, delays photoreceptor loss in this hereditary retinal degeneration. Repeated injections maintain the protective effect.  相似文献   
74.
The Dunning R3327 rat carcinoma is an important model for human prostate adenocarcinoma. In the present study this tumor was further characterized by immunohistochemical demonstration of receptors for growth hormone (GH-R). Weak GH-R immunoreactivity was present in the secretory epithelial cells of the tumor acini. Large epithelial cells which were localized at the periphery of the acini and large cells in the stroma, which are probably derived from the epithelium ("Large neoplastic epithelial cells"), displayed a strong staining with one of the monoclonal antibodies (Mab 263) to GH-R. The presence of GH-R receptors in proliferating prostatic tumor cells supports the concept that GH reacts directly on prostate target tissue to facilitate tumor cell growth.  相似文献   
75.
A simple auto-evaluation sheet is presented for the proper assessment of the patient's condition after surgery. Stress is put not only on weight loss, but on other important factors as well.  相似文献   
76.
Results of treatment in 72 children with a relapse of acute lymphoblastic leukaemia were analysed. A second remission was induced in 57 children (79%). Remission rates were significantly higher in males, and in patients with white cell counts less than 30 X 10(9)/L. The median duration of the second remission was only four months, and the median duration of survival from the time of relapse was nine months. The median duration of survival from the time of diagnosis was 27 months. Among children who suffered a relapse was a small group who had prolonged survival and prolonged second remissions. It is uncertain whether some of these may have a chance of "cure".  相似文献   
77.
PURPOSE: We identify predictors of extraprostatic extension and positive surgical margins in patients with low risk prostate cancer (prostate specific antigen [PSA] 10 ng./ml. or less, biopsy Gleason score 7 or less and clinical stage T1c-2b). MATERIALS AND METHODS: From August 1997 to January 1999, 143 previously untreated patients underwent radical retropubic prostatectomy for clinically localized prostate cancer. A total of 62 patients were low risk, with PSA 10 ng./ml. or less, biopsy Gleason score 7 or less and clinical stage T1c-2b, and had sextant biopsy with separate pathological evaluation of each sextant cores. PSA, clinical stage, biopsy Gleason score, average percentage of cancer in the entire biopsy specimen, maximum percentage of cancer on the most involved core, number of cores involved and bilaterality were evaluated for association with extraprostatic extension, seminal vesicle involvement and positive surgical margins. RESULTS: Of the 62 patients 13 (21%) had extraprostatic extension, 6 (10%) seminal vesicle involvement and 20 (32%) positive surgical margins. Average percentage greater than 10% and maximum percentage greater than 25% were associated with extraprostatic extension (p = 0.01 and 0.004, respectively). Average percentage greater than 10%, maximum percentage greater than 25%, more than 2 cores involved and bilaterality were associated with positive surgical margins (p = 0.007, 0.01, 0.002 and 0.03, respectively). On multivariate analysis maximum percentage remained the only independent predictor of extraprostatic extension (p = 0.03), and the number of cores involved remained an independent predictor of positive surgical margins (p = 0.01). Biopsy Gleason score, PSA and clinical stage did not correlate with extraprostatic extension or positive surgical margins in this patient population. CONCLUSIONS: In low risk prostate cancer the extent of biopsy involvement significantly correlates with the risk of extraprostatic extension and positive surgical margins. Biopsy information should be considered when selecting and modifying treatment modalities.  相似文献   
78.

Background  

Our goal was to quantify the evidence that is available to the physicians of a pediatric emergency department (PED) in making treatment decisions. Further, we wished to ascertain what percentage of evidence for treatment provided in the PED comes from pediatric studies.  相似文献   
79.
80.
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