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41.
A plasmid encoding streptomycin-resistance could be detected in 13 of 32 Pasteurella multocida-cultures isolated from cattle and swine. The plasmid of these cultures proved to be similar upon Southern blot hybridization. It could be transformed into Escherichia coli 490A, where it also expressed streptomycin resistance. 相似文献
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Out of 1041 patients who underwent surgery for gastric cancer between 1968 and 1987, 120 patients suffered from early gastric cancer (11.5%). Until 1976, early gastric cancer was treated along the lines of surgical treatment of benign ulcer disease, i.e. by partial 2/3-gastric resection without lymphadenectomy, even though malignancy had been confirmed preoperatively in all cases. Since 1979 oncological criterias (subtotal or total gastrectomy with lymphadenectomy) have gained importance in treating early gastric carcinoma. In the case of mucosal carcinoma, the extent of surgical intervention does not have any influence on the 10-year survival rate. In treating submucosal carcinoma 10-year survival rates of 72.9 (+/- 7.2%) can only be achieved by performing total gastrectomy and lymphadenectomy whereas the 10-year survival rate after performing partial 2/3-gastric resection alone (p = 0.01) is only 17.6 (+/- 9.2%). Since mucosal and submucosal carcinoma cannot accurately be differentiated preoperatively, surgical intervention must be carried out in an oncological sense. The fact that 2/3 partial gastric resection does not generally ensure adequate therapy implies that local procedures are even less sufficient. Even in cases of mucosal infiltration only, local procedures such as laser therapy and local excision of the tumour cannot be considered being a curative approach, since hereby the probability of lymph node metastases (4%) is not taken into account. 相似文献
44.
We evaluated the Kodak Ektachem clinical chemistry slide for assay of theophylline. Assay precision and accuracy were acceptable in the therapeutic range although precision was poor at low levels of theophylline. The assay performed well with patients' samples using the Abbott TDx as the reference procedure but, as indicated by the manufacturer, uremic samples gave a positive bias, particularly in the therapeutic range. Finally, the significant bias observed with Quality Control material, probably due to matrix sensitivity, is a possible drawback. 相似文献
45.
Summary Isolated angiitis of the central nervous system (IAC) was diagnosed in a 40-year-old Caucasian male by histological examination of a leptomeningeal biopsy specimen, and the exclusion of systemic inflammatory or infective disease. Therapy with prednisone 30 mg/day and cyclophosphamide 100 mg/day resulted in clinical and radiological improvement, which have been maintained for an 8-month follow-up period. Magnetic resonance imaging (MRI) showed lesions implicating involvement of specific penetrating vessels at the base of the brain, an unusual complication of IAC, and allowed an accurate MRI-clinical correlation. 相似文献
46.
T B?ttger S St?rkel M St?ckle W Wahl A Heintz M Jugenheimer O Effenberger-Kim T Vinh T Junginger 《Der Chirurg》1991,62(6):467-72; discussion 472-3
Esophagus cancer is a heterogeneous disease with considerable differences in malignant behaviour. Some relevant factors for prognosis are known. In this study we analyzed DNA-ploidy as a potential prognostic parameter in esophagus carcinoma. Paraffin embedded histological material from 50 patients with an esophagus cancer, obtained by resection, were selected for analysis. Tumor areas within the paraffin material were identified by HE-stained reference sections. One 50 microns section was dewaxed, rehydrated and mechanically and enzymatically treated to a suspension of 10,000 cells/ml. 1 ml of the suspension, containing bare nuclei with small rests of cytoplasma was centrifuged on glass slides. The fixed nuclei were air-dried and stained by Feulgen-SITS technique, which allows quantitative measurement of DNA. The DNA analysis was carried out with a computer-controlled single cell cytophotometry (Leytas 2, Leitz, Wetzlar). In contrast to the flow cytometry with image cytometry only tumors cells were measured. Overlapping nuclei, dirt and other artefacts as well as inflammatory cells were efficiently eliminated. With the DNA image cytometry we could differentiate between diploid and hypotriploid, hypertriploid aneuploid tumors. Best prognosis had diploid and hypotriploid tumors, the worst hypertriploid carcinomas. In the multivariate analysis the DNA-content of the tumor cells in esophagus cancer was the only prognostic parameter. DNA-content of tumor cells may become considerably clinical relevant in esophagus cancer for the decision to perform a resection or palliative treatment. In patients with hypertriploid tumors an adjuvant oncological therapy may increase the prognosis. 相似文献
47.
Summary The metabolic potency of recombinant human insulin-like growth factor II was studied in anaesthetized adult rats by obtaining dose-response curves for the hypoglycaemic action and for the stimulation of glucose metabolism during euglycaemic clamping. Compared to insulin, about 50 times higher doses of insulin-like growth factor II were required to result in identical in vivo responses, with half-maximally effective serum concentrations for the stimulation of glucose disposal during clamp studies of about 0.8 and 50 pmol/ml, respectively. A similar difference in potency was observed for the dose-dependent stimulatory actions on glucose metabolism in individual target tissues. Half-maximally effective serum concentrations in the range of 0.8 to 3.0 pmol/ml for insulin and of 40 to 70 pmol/ml for insulin-like growth factor II were seen to be required for 2-deoxyglucose uptake, glycogen formation in skeletal muscle and lipogenesis in epididymal fat. Maximal responses were identical with both peptides. These data suggest that in vivo acute metabolic actions of insulin-like growth factor II on carbohydrate metabolism occurred through insulin receptors. 相似文献
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50.
Matthias Bollow Wolfgang Knauf Agnieszka Korfel Matthias Taupitz Andreas Schilling Karl-Jürgen Wolf Bernd Hamm 《Journal of magnetic resonance imaging : JMRI》1997,7(1):241-250
The purpose of this study was (a) evaluation of dynamic contrast-enhanced MR imaging of normal bone marrow versus malignant bone marrow infiltrations in patients with proven B-cell-type chronic lymphocytic leukemia (B-CLL) and (b) correlation with the clinical stage according to Binet (stages A, B, C) and response to therapy. Bone marrow imaging of the lumbar spine, pelvis, and proximal femurs was performed at 1.5 T in 45 patients without known malignancy and in 30 patients with B-CLL. The differences between opposed-phase and in-phase dynamic gradient-echo sequences before and up to 10 minutes after intravenous application of .1 mmol/kg body weight of gadolinium-diethylenetriamine penta-acetic acid (Gd-DTPA) were evaluated in normal bone marrow. The contrast-enhancement patterns of normal and malignant bone marrow were compared using the opposed-phase dynamic gradient-echo sequence. Ten of the patients with bone marrow infiltrations (Binet stage C) additionally underwent MR imaging follow-up during therapy. Opposed-phase gradient echo sequences demonstrated a signal decrease of normal bone marrow, and in-phase gradient echo sequences demonstrated a signal increase of normal bone marrow after administration of Gd-DTPA. The dynamic signal intensity time courses differed significantly (P < .05) between Binet stages B and C and controls as well as among the three Binet stages of B-CLL. In the 10 patients followed during therapy, MR imaging sensitively demonstrated response (n = 6), nonresponse (n = 2), or relapse after initial response (n = 2). In out-of-phase imaging, both normal bone marrow and initial bone marrow infiltration in CLL stage Binet A show signal decrease after administration of contrast agent, whereas there is increase in signal intensity in higher-grade bone marrow infiltration in Binet stage B or C disease. The signal loss of normal bone marrow in out-of-phase imaging is a phase effect rather than a T2* effect. The differentiation of initial from higher-grade bone marrow infiltration on out-of-phase images relies solely on a shift in the fat/water ratio. 相似文献