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41.
目的对比短程化疗含链霉素(SM)、乙胺丁醇(EMB)两组方案在抗结核治疗中的效果。方法选初治菌阳肺结核100例,予含SM方案(2HRZS/7HR)化疗50例,含EMB方案(2HRZE/7HR)化疗50例。每月检查痰结核菌一次(涂片三次,培养一次)。停药后继续追踪两年。结果痰菌2个月内转阴者,SM组29例,占63%;EMB组18例,占38%,p<0.05,有显著性差异。需延长强化期者:SM组16例,占35%;EMB组26例,占55%,p<0.05,有显著性差异。复发病例,SM组2例,占4%;EMB组3例,占6%,p>0.05,无显著性差异。结论使用含SM方案化疗的病例其痰菌转阴时间比含EMB方案短。 相似文献
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The use of deep inspiration preceding the valsalva maneuver and rapid expiration in color doppler imaging of the lower extremity veins 总被引:1,自引:0,他引:1
Jing Gao MD Elias Kazam MD William Rubenstein MD Joseph P. Whalen MD Tom Hom RDMS RT 《Clinical imaging》1993,17(4):266-268
Deep inspiration preceding Valsalva maneuver and rapid expiration immediately following it (DIVE) enhance venous blood flow on color Doppler flow imaging (CDI). The effect of DIVE was assessed in 115 consecutive lower extremity examinations. Of these, 95 or 115 (83%) had negative CDI sonograms, and 20 of 115 (17%) had partially (six of 115) or completely (14 of 115) occluding deep vein thrombosis. DIVE enhanced venous blood flow in 68% of the negative cases, resulting in transient venous distention, and/or more complete color filling, and/or greater spectral flow velocities. The 14 cases with completely occluding thrombi showed no response to DIVE. Six cases with partially occluding thrombi showed moderate to mild response to DIVE, with improved color delineation of the residual patent lumen around the thrombus. The authors conclude that DIVE facilitates deep venous CDI, especially when compression cannot be used to augment venous flow. 相似文献
44.
Robert M. Judd Michael K. Atalay Gerald A. Rottman Elias A. Zerhouni 《Magnetic resonance in medicine》1995,33(2):215-223
Interpretation of first-pass myocardial perfusion studies employing bolus administration of T1 magnetic resonance (MR) contrast agents requires an understanding of the relationship between contrast concentration and image pixel intensity. The potential effects of myocardial water exchange rates among the intravascular, interstitial, and cellular compartments on this relationship are controversial. We directly studied these issues in isolated, nonbeating canine interventricular septa. Myocardial T1 was measured three times/s during bolus transit of intravascular (albumin-Gd-DTPA and poly-lysine-Gd-DTPA) and extracellular (gadoteridol) contrast agents. For polylsine-Gd-DTPA, the peak changes in myocardial 1/T1 (ΔR1) scaled nonlinearly with perfusate contrast concentration whereas a linear relationship would be expected for fast water exchange among the vascular, interstitial, and cellular compartments. For all agents, the peak ΔR1 were much smaller than the values expected on the basis of fast myocardial water exchange. The data demonstrate that in isolated myocardial tissue, myocardial T1 enhancement during bolus administration of contrast can be strongly affected by myocardial water exchange for both intravascular and extracellular MR contrast agents. 相似文献
45.
Desensitization of the insulin receptor by antireceptor antibodies in vivo is blocked by treatment of mice with beta-adrenergic agonists. 总被引:1,自引:0,他引:1 下载免费PDF全文
In previous studies we reported that immunization of mice with ungulate insulins induced the development of antiinsulin antibodies, which include an idiotype that appeared to recognize the part of the insulin molecule recognized by the hormone receptor. The antiinsulin antibodies of this idiotype were replaced spontaneously by antiidiotypic antibodies. The antiidiotypic antibodies, which persisted for about 14 d, mimicked insulin and functioned as antibodies to the insulin receptor. They induced down regulation, desensitization and refractoriness of the insulin receptor and disturbances in glucose homeostasis in vivo (Shechter, Y., D. Elias, R. Maron, and I.R. Cohen., 1984; Elias, D., R. Maron, I.R. Cohen, and Y. Shechter. 1984, J. Biol. Chem. 259: 6411-6419). We now report that effects of the antiidiotypic antibodies on the insulin receptor effector system can be modified pharmacologically. Administration of the beta-adrenergic agonist isoproterenol during the period of insulin resistance (days 26-40 after primary immunization), largely restored fat cell responsiveness to insulin, and eliminated the appearance of fasting hyperglycemia. This restoration appeared to be caused by inhibition of both insulin receptor desensitization and refractoriness. In contrast, down regulation of insulin receptors was not reversed by isoproterenol treatment in vivo. The effects of treatment with isoproterenol persisted for 2-4 d after termination of treatment. The beta-antagonist, propranolol and more so, the beta 1a-antagonist metoprolol, specifically blocked the effect of isoproterenol at a molar ratio of 3-10:1. Oral administration of the cAMP phosphodiesterase inhibitor, aminophylline, was also effective in inhibiting the development of desensitization in fat cells. These results indicate that treatment with beta 1-adrenergic agonists in vivo, or other agents that elevate cellular cAMP levels, can inhibit the development of the "postbinding" defects induced by insulin-mimicking, antireceptor antibodies. These observations have both basic and clinical implications. 相似文献
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48.
Schistosomiasis: an unusual cause of tubal infertility 总被引:3,自引:0,他引:3
Balasch Juan; Martinez-Roman Sergio; Creus Montserrat; Campo Elias; Fortuny Albert; Vanrell Juan A. 《Human reproduction (Oxford, England)》1995,10(7):1725-1727
A case report of a Nigerian woman having an unusual cause oftubal infertility is presented. On histological examinationof the Fallopian tube, ova of Schistosoma haematobium enclosingliving miracidia were found in the smooth muscle layer of theFallopian tube and its mesosalpinx. Mechanisms of tubal involvementare analysed. The case indicates the need to consider schisto-somiasisas a possible aetiological factor in patients with tubal infertilitycoming from areas where the disease is endemic. 相似文献
49.
50.
Hans-G. Elias 《Macromolecular chemistry and physics.》1994,195(9):3117-3131
Ultimate mechanical properties of polymers can be characterized by a dimensionless Hooke number He ≡ σb/(E?b), where σb is the ultimate tensile strength, E the tensile modulus, and ?b the elongation at break. Hooke numbers are found to be a smooth function of ultimate elongations, independent of the chemical and physical structure of common thermoplastics. This master curve for fracture strengths and elongations can be described by He = [1 + (?b/?crit)ab]?1/b with empirically found parameters ?crit = 0,0168, a = 0,918, and b ≈ 4. The decrease of He with increasing ?b at ?b > ?crit reflects the shear flow on deformation. Hooke numbers depend on entanglement densities ve according to He = 1,285·1036 (ve/cm?3)?1,846 for ve > 3,65·1019 cm?3. A correction for additional segment orientation during tensile testing brings the exponent to ?1,846/0,918 = ?2,01; i. e., a dependence of Hooke numbers on the reciprocal square of entanglement densities. 相似文献