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11.
胆结石是常见多发病, 但临床缺乏有效的治疗药物. 饱和脂肪酸与胆酸的缀合物能有效预防胆固醇结晶、溶解体内胆固醇结石. 以胆酸或熊去氧胆酸24位羧基为连接位点, 以氨基酸为连接子, 通过酰胺键将载体与具有溶石活性的饱和脂肪酸偶联, 设计合成了一系列新型脂肪酸胆酸缀合物, 其结构经元素分析, IR, 1H NMR和MS光谱分析确证. 通过测定化合物对模型胆汁溶液胆固醇结晶及模型小鼠胆结石的溶解活性, 研究了其体内外溶石活性.  相似文献   
12.
胆结石的微观结构和组成元素研究   总被引:4,自引:0,他引:4  
用扫描电镜研究了胆色素型和混合型胆结石经氯仿、乙醇、乙醚、盐酸等溶剂溶解剩余物的微观结构,结果显示色素型结石难溶物为膜孔相连结构,两层膜之间填充颗粒状盐;混合型结石难溶物的微观结构为絮状物连接的网孔结构,盐类嵌镶在絮状物中。用X射线能谱仪和等离子体发射光谱仪分析了胆结石的元素,讨论了金属元素在结石中所起的作用。  相似文献   
13.
目的:分析研究脂肪肝与胆囊结石的相互关系.方法:超声检查3459名到本院体检中心的事业单位人员,按脂肪肝及结石的诊断标准检查其发病情况并进行研究分析.结果:受检的3459名人员中,脂肪肝患病率为26.63%,胆囊结石患病率为8.44%,脂肪肝男性患病率明显高于女性(P<0.01).根据超声检查结果将受检者分为脂肪肝组和...  相似文献   
14.
Our serial studies from 1970s on chemical composition, structure determination and formation mechanism of gallstones were reviewed. The chemical component investigation of brown-pigment gallstone demonstrated that it consists of macromolecules such as proteins, glyco-proteins, polysaccharides, bilirubin polymers and pigment polymers, and biomolecules such as cholesterol, bile salts, calcium salts of carbonate, phosphate, fatty acids and bilirubinate as well as various metal ions. The binding of metal ions with bile salts and bilirubin plays important roles in gallstone formation, i.e., calcium bilirubinate complex is the major constitute of brown-pigment gallstones, and copper bilirubinate complex is critical in the black color appearance of black-pigment gallstone. The cross section of many gallstones exhibits a concentric ring structure composed of various small particles with a fractal character. This is nonlinear phenomenon in gallstone formation. A typical model system of metal ions-deoxycholate (or cho  相似文献   
15.
Animal biles and gallstones are popularly used in traditional Chinese medicines, and bile acids are their major bioactive constituents. Some of these medicines, like cow-bezoar, are very expensive, and may be adulterated or even replaced by less expensive but similar species. Due to poor ultraviolet absorbance and structural similarity of bile acids, effective technology for species differentiation and quality control of bile-based Chinese medicines is still lacking. In this study, a rapid and reliable method was established for the simultaneous qualitative and quantitative analysis of 18 bile acids, including 6 free steroids (cholic acid, chenodeoxycholic acid, deoxycholic acid, lithocholic acid, hyodeoxycholic acid, and ursodeoxycholic acid) and their corresponding glycine conjugates and taurine conjugates, by using liquid chromatography coupled with tandem mass spectrometry (LC/MS/MS). This method was used to analyze six bile-based Chinese medicines: bear bile, cattle bile, pig bile, snake bile, cow-bezoar, and artificial cow-bezoar. Samples were separated on an Atlantis dC18 column and were eluted with methanol–acetonitrile–water containing ammonium acetate. The mass spectrometer was monitored in the negative electrospray ionization mode. Total ion currents of the samples were compared for species differentiation, and the contents of bile acids were determined by monitoring specific ion pairs in a selected reaction monitoring program. All 18 bile acids showed good linearity (r2 > 0.993) in a wide dynamic range of up to 2000-fold, using dehydrocholic acid as the internal standard. Different animal biles could be explicitly distinguished by their major characteristic bile acids: tauroursodeoxycholic acid and taurochenodeoxycholic acid for bear bile, glycocholic acid, cholic acid and taurocholic acid for cattle bile, glycohyodeoxycholic acid and glycochenodeoxycholic acid for pig bile, and taurocholic acid for snake bile. Furthermore, cattle bile, cow-bezoar, and artificial cow-bezoar could be differentiated by the existence of hyodeoxycholic acid and the ratio of cholic acid to deoxycholic acid. This study provided bile acid profiles of bile-based Chinese medicines for the first time, which could be used for their quality control.  相似文献   
16.
本工作选择牛磺胆酸钠作为人体内胆汁酸盐的代表研究其对胆色素结石的重要成分——胆红素钙沉淀过程的影响。结果表明,牛磺胆酸钠的存在使胆红素钙沉淀的条件溶度积大大提高,并使沉淀反应速度大大减慢。在牛磺胆酸钠浓度较高的情况下,沉淀过程出现诱导期,说明牛磺胆酸钠在一定条件下可以抑制胆红素钙沉淀的形成。沉淀的红外光谱表明,牛磺胆酸并未结合在沉淀中,也未影响沉淀中胆红素与钙离子间的相互作用的部位。沉淀的扫描电镜观察结果经统计学处理表明牛磺胆酸钠的存在使沉淀的颗粒变小,颗粒的聚集程度减小。  相似文献   
17.
In this investigation two calcium bilirubinates compounds, Ca(HBR)2·H2O and Ca(BR)·2H2O, were prepared. Their Fourier transform infrared spectra were measured in KBr discs and in fluorolube and nujol mulls, respectively. The results suggest that it is better to identify the Ca(HBR)2·H2O and Ca(BR)·2H2O with fluorolube and/or nujol mulls when examining mixtures (e.g. gallstone).  相似文献   
18.
Abstract

This review assesses the applications of laser-induced breakdown spectroscopy (LIBS) for the analysis of a variety of samples, including biomaterials (teeth, nail, hair, gallstones, and kidney stones, etc.), food materials (fruits and vegetables, milk, salt, nutritional supplements, etc.), medicinal plants, industrial waste, liquid samples, etc. In addition, for the first time the identification of cholesterol and pigment stones was performed on the basis of atomic lines of different elements and molecular bands of C2 molecules present in the LIBS spectra of gallstones. Chemometric techniques such as principal component analysis (PCA) was also applied to LIBS data for rapid identification/classification of different gallstone samples. LIBS analysis of toxic/heavy elements present in vegetables (spinach, tomato) and rice is also presented in this review. It was observed that vegetables grown near industrial areas are rich in several toxic metals like Pb and Cr. The wastewater samples from different industries were also analyzed by recording their spectra using a liquid jet. These results clearly demonstrate the ability of LIBS technique as an instant monitoring device to detect heavy metals present in liquid samples. Finally, this review shows that LIBS is a versatile analytical technique with unlimited applications.  相似文献   
19.
Nd:YAG激光器在治疗胆结石方面的应用与展望   总被引:3,自引:0,他引:3  
李丽  叶志生  金贞姬 《应用激光》2003,23(5):317-319
本文重点介绍的激光碎石术的的机理及Nd :YAG激光碎石机的发展状况 ,并根据我国现状 ,提出现阶段对于激光碎石机的研究应重点放在五个方面 ,从而降低成本 ,提高碎石效率及安全性 ,使其更加广泛的应用于结石病的治疗  相似文献   
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