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肺神经内分泌癌的免疫组化与免疫电镜研究   总被引:3,自引:1,他引:3  
本文应用免疫组化与免疫电镜技术对20例肺神经内分泌癌进行了研究,另6例非神经内分泌癌作为对照。结果表明:嗜铬颗粒蛋白A免疫组化染色19/20例阳性,免疫电镜能够比较特异地标记神经分泌颗粒,具有确诊意义;神经特异性烯醇化酶染色20/20例阳性,非神经内分泌癌3/6例阳性,免疫电镜下无特异性分布,适宜作为诊断的筛选指标;S-100蛋白和5-HT亦可作为诊断之参考。  相似文献   
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We hypothesized that walking at increased speed or increasing gradient might have different effects on chest wall kinematics and respiratory muscle power components, and contribute differently to respiratory effort sensation. We measured the volumes of chest wall compartments by optoelectronic plethysmography, esophageal, gastric and transdiaphragmatic (P di) pressures, and the sensation of the respiratory effort by a Borg scale in five normal subjects walking both at ascending gradient with constant speed (AG) and at ascending speed with constant gradient (AS). Chest wall kinematics, evaluated by displacement of chest wall compartments, did not show any significant difference between AS and AG. Muscle power, calculated as the product of mean flow and mean pressure, increased similarly, but its partitioning into pressure and velocity of shortening differed in the two modes. A greater increase in the pressure developed by the abdominal muscles (P abm) (4.06-fold), and in the velocity of shortening of both rib cage inspiratory muscles (v rcm,i) (2.01-fold) and the diaphragm (v di) (1.90-fold) was associated with a lower increase in the pressure developed by the rib cage inspiratory muscles (P rcm,i) (1.24-fold) and P di (0.99-fold) with AG. Instead, with AS, a lower increase in P abm (2.12-fold), v rcm,i (1.66-fold) and v di (1.54-fold) was associated with a greater increase in P rcm,i (1.56-fold) and P di (1.97-fold). A combination of P abm and v di during AG (Wald 2=23.19, P<0.0000), with the addition of P rcm,i during AS (Wald 2=29.46, P<0.0000), was the best predictor of Borg score. In conclusion, the general strategy adopted by respiratory centers during different walking modes does not differ in terms of ventilation, chest wall kinematics, and respiratory muscle power production, whereas it does in terms of partitioning of power into pressure and velocity of shortening, and respiratory muscle contribution to respiratory effort sensation. Combinations of different patterns of flow and pressure generation made the respiratory effort sensation similar during AS and AG modes.  相似文献   
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In the past few years research on stem cells has exploded as a tool to develop potential therapies to treat incurable neurodegenerative diseases. Stem cell transplantation has been effective in several animal models, but the underlying restorative mechanisms are still unknown. Several events such as cell fusion, neurotrophic factor release, endogenous stem cell proliferation, and transdifferentiation (adult cell acquisition of new unexpected identities) may explain therapeutic success, in addition to replacement of lost cells. This issue needs to be clarified further to maximize the potential for effective therapies. Preliminary stem transplantation trials have already been performed for some neurodegenerative diseases. There is no effective pharmacological treatment for amyotrophic lateral sclerosis, but recent preliminary data both in experimental and clinical settings have targeted it as an ideal candidate disease for the development of stem cell therapy in humans. This review summarizes recent advances gained in stem cell research applied to neurodegenerative diseases with a special emphasis to the criticisms put forward.  相似文献   
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Cutaneous mucormycosis in a young, immunocompetent girl.   总被引:2,自引:0,他引:2  
We report a case of cutaneous mucormycosis in a healthy, immunocompetent young girl (age 14 years). The patient had a 5-year history of a slowly enlarging, erythematous plaque with slight elevated, scaling, circinate borders on the right thigh. Histopathology showed a granulomatous infiltrate with broad, pale, non-septate hyphae. Mycological study identified Mucor hiemalis (Wehmer).  相似文献   
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The nature of high frequency sister chromatid exchange cells (HFCs)   总被引:1,自引:0,他引:1  
We employed the three-way differential staining technique (TWD),which allows SCEs to be distinguished on a per generation basisby scoring third metaphases (M3), in order to study the spontaneouslevels of SCEs in normal and high frequency cells (HFCs) thatoccurred in the first (S1), second (S2) and third (S3) S phases.Fifty one of 900 lymphocytes from 37 healthy donors were definedas HFCs by calculating the 95th percentile of the distributionof SCEs in S1 + S2. ‘Normal’ cells presented almostthe same number of SCEs after the first, second and third cellcycles (SCE averages of 2.43, 2.04 and 3.53 respectively). Incontrast, HFCs showed a higher SCE count in SI, which decreasedrapidly through the cycles and reached baseline level at S3(SCE averages of 7.18, 4.29 and 3.45 respectively). This wouldsuggest that the lesions responsible for the higher SCE frequencyin HFCs were effectively removed after two cell cycles and stronglysupport the hypothesis that HFCs are lymphocytes which accumulatehigher levels of DNA lesions through time. 1To whom correspondence should be addressed  相似文献   
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