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21.
测定了Gemini表面活性剂在pH值为10.86,NaBr浓度为1.0mol/L的溶液气/液界面上的表面压一分子面积的等温线。用自制的Brewster角显微镜(BAM)观察了由Gemini表面活性剂在界面上所形成单分子膜的微区形貌随表面压的变化。结果表明:当pH值为10.86时,Gemini表面活性剂在1.0mol/L NaBr溶液的气/液界面上生成了凝聚态的单分子膜;当表面压较低时,观察到在界面上形成了同心圆结构;随着表面压的增加,这些同心圆可发生聚并而形成多中心结构。  相似文献   
22.
Papillary adenoma of the prostatic urethra: Report of two cases   总被引:1,自引:0,他引:1  
Papillary adenoma of the prostatic urethra is a rare cause of hematuria, hemospermia and lower urinary tract obstruction, especially in young adults. We report two cases of papillary adenoma and their endoscopic views. One of the patients had a lesion located on the verumontanum and presented with hematuria, hemospermia and symptoms of lower urinary tract obstruction. The other patient had papillary lesions located in the paramontanal gutter and presented with persistent painless hematuria. The origin of both lesions was proven to be prostatic epithelial differentiation using immunohistochemical identification of prostate-specific antigen. Papillary adenoma is believed to be benign, therefore, both lesions were carefully excised and fulgurated transurethrally.  相似文献   
23.
目的 探讨双探头SPECT心肌灌注显像时位移伪影的影像特征和识别方法。方法 将心脏模型置于检查床上,与受检患者的心脏方向一致。在图像采集过程中,模型依次沿相当于患者左右、头尾和前后方向分别在不同起始点、对不同帧数作一定距离的位移。结果位移伪影的共同特点是表现为室壁放射性分布不均匀,“热区”与“冷区”交替出现,在短轴上最早出现,且表现最为明显;伪影进一步发展会在水平长轴和垂直长轴上表现为心尖附近放射性稀疏或缺损,出现与相邻室壁伴行且形态相近的“伴影”。结论位移伪影主要表现为室壁放射性分布不均,“热区”与“冷区”交替出现,在短轴图像上易于早期发现。  相似文献   
24.
Sagone  AL Jr; Balcerzak  SP; Metz  EN 《Blood》1975,45(1):49-54
In this investigation, we studied the importance of cellular glutathione (GSH) in the hexose monophosphate shunt (HMPS) activity of unstimulated human erythrocytes and the mechanism by which pyruvate stimulates the HMPS. The rate of HMPS activity was measured by the production of radioactive CO2 from 14C-1-glucose or 14C-1-ribose using a vibrating reed electrometer and ionization chamber. HMPS activity was not significantly impaired by N-ethylmaleimide (NEM) in concentrations which bound all red cell GSH. Red cells incubated under carbon monoxide (CO), an experimental condition which eliminates peroxide production, still had HMPS activity which was 44% of the value under air. Pyruvate stimulation of the HMPS was unaffected by doses of NEM which bound all cellular GSH or by incubation under CO. These data indicated that pyruvate stimulation of the HMPS occurs by pathways which do not involve peroxide formation, GSH, or oxygen. This study indicates that sulfhydryl blockade of GSH does not necessarily inhibit HMPS activity and that HMPS activity in red cells may respond to reactions not linked directly to glutathione reduction.  相似文献   
25.
目的探讨老年冠心病合并糖尿病患者经皮冠状动脉介入(PCI)置入雷帕霉素洗脱支架(SES)治疗的远期疗效。 方法回顾性随机入选2003年1月至2007年12月住院期间老年冠心病合并糖尿病患者行PCI 100例,并入选同时期100例无糖尿病的冠心病患者行PCI为对照组。随访5年,随访包括心绞痛复发、死亡、心肌梗死、卒中和再次血运重建的主要不良心脑血管事件。结果 两组支架术成功率均为100%。随访率100%,随访5年,糖尿病组与非糖尿病组术后并发症发生率(8.0%、7.0%)、卒中发生率(5%、3.0%)、心源性死亡率(0%、0%)差异无显著性(均为ρ〉0.05)。再次血运重建率(30.0%、14.0%)、非致死性心肌梗塞(6.0%、2.0%)心绞痛复发率(42%、20%)、全因死亡率(10%、2.0%)糖尿病组高于非糖尿病组;但心源性病死率均为0%。结论:老年患者选择性冠脉内置入药物洗脱支架安全,成功率高,远期疗效尚好,但糖尿病仍是远期不良预后的独立预测因素。  相似文献   
26.
Abstract: Pityriasis rosea (PR) is an acute, self‐limiting papulosquamous disorder of unknown etiology. Published studies of childhood PR are scarce and most are reviews. The aim of this study was to determine the demographic and clinical features of childhood PR.  相似文献   
27.
宁夏贝母化学成分的研究   总被引:3,自引:0,他引:3  
从宁夏贝母(Frdillapia taipaiensis P. Y. Li var. ningxiaensis Y. K. Yang et. J. K. Wu)的鳞茎中分得六个异甾体生物碱成分,鉴定为宁贝素(taipaienine,Ⅰ)、川贝酮(chuanbeinone,Ⅱ)、西贝素(imperialine,Ⅲ)、贝母乙素(verticinone,Ⅳ)、贝母辛(peimissine,Ⅴ)和异贝母甲素(isoverticine,Ⅵ).其中T为一新C-去甲-D-高甾生物碱。应用波谱分析(IR,MS,1HNMR和13CNMR)等确定了它们的化学结构。  相似文献   
28.
Computed tomography (CT) was used to study 25 patients with congenital conductive hearing loss and normal external auditory canals. Deformities were subdivided according to ossicular, fenestral, and cholesteatomatous origin. Isolated ossicular deformities were found in 14 patients (five bilateral), cholesteatoma in eight, oval-window nondevelopment (with ossicular deformity) in one, and normal studies in two (congenital stapes fixation at the level of the annular ligament). Ossicular deformities may be subdivided into incudostapedial disconnections into incudostapedial disconnections (most common), malleoincudal fixations, and stapes fixations. Most are due to developmental anomaly of the first or second branchial arch. The stapes has a dual origin (second arch and otic capsule). A cholesteatoma is defined as congenital only if there is no history of otitis and the tympanic membrane is intact. In this series, six were in the middle ear proper, and two were within the attic beyond otoscopic view. Their CT appearance, with one exception, was essentially identical to that of acquired lesions.  相似文献   
29.
Which factors may influence the number of hours spent per week in cafes, and the amount of alcohol consumed in licensed premises, by urban cafe guests in Norway? In 1991 a comprehensive questionnaire survey was undertaken among 1053 visitors to 41 licensed cafes in Oslo, Norway. The five most important predictors of time spent in cafes were: household situation (β=0.20), occupation (β= 0.18), personal economic resources and sex (both β= 0.15) and age (β= 0.11). These factors were also significant predictors of the number of days during the past 4 weeks the respondents had drunk jour glasses or more of alcohol in cafes. Men, people living with others, people with poor economic resources and people not engaged in paid employment or education were the ones who reported spending the most hours per week and the most episodes of “heavy” drinking in cafes during a 4-week period. Visiting and drinking in cafes may be a way of structuring everyday life.  相似文献   
30.
Outcome of the treatment of invasive non-transitional cell carcinoma   总被引:1,自引:0,他引:1  
BACKGROUND: We evaluated the treatment outcomes of non-transitional cell carcinoma (non-TCC) cases after radical cystectomy. METHODS: Radical cystectomy was performed in 259 invasive bladder cancer patients in our department and of these, 59 (22.7%) were non-TCC. Primary squamous cell carcinomas (SCC), adenocarcinomas and undifferentiated cancers (UC) were grouped as non-TCC of the bladder. Of the 59 non-TCC; 32 SCC, 20 UC, five adenocarcinoma and two sarcomatoid tumor cases were demonstrated. RESULTS: The 5-year disease-specific survival rate of TCC and non-TCC cases were 48.9 and 28.2%, respectively (P = 0.0016). The 5-year disease-specific survival rates of SCC and UC were 25.1 and 23.4%, respectively. The median survival time of SCC, UC and adenocarcinoma cases were 19, 12 and 6 months, respectively (P = 0.4579). The disease-specific survival rates of TCC and non-TCC cases at stage pT2NoMo were 79.1 and 27.2%, respectively (P = 0.0000). The median survival time of SCC, UC and adenocarcinoma cases were 19, 12 and 13.3 months, respectively, for the same stage. The survival time of TCC, SCC and UC cases at stage pT3NoMo were 23, 26 and 45 months, respectively (P = 0.2307). The median survival time at stages pT2-3N1Mo for the same groups were 18, 16 and 11 months, respectively (P = 0.0939). CONCLUSION: The study presented here demonstrates that both TCC and non-TCC cases have poor survival rates in locally advanced disease and that at the pT2NoMo stage the prognosis of non-TCC cases is poor when compared with TCC cases.  相似文献   
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