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1.
游离胆红素与固体碳酸钙的相互作用   总被引:2,自引:0,他引:2  
应用红外光谱的方法研究了溶液中游离胆红素与固体碳酸钙的相互作用,探讨了色素型胆结石的形成机理.研究结果表明,溶液中游离的胆红素可以与固体碳酸钙作用,游离胆红素通过与固体碳酸钙表面的钙作用生成难溶性的胆红素钙络合物.牛磺胆酸钠、胆酸钠和脱氧胆酸钠的加入能阻止游离胆红素与碳酸钙的作用,其中加入牛磺胆酸钠后,游离胆红素几乎不与碳酸钙作用.  相似文献   

2.
胆盐与磷酸钙的相互作用   总被引:2,自引:0,他引:2  
胆汁的pH条件下(pH=6~8),应该生成无定形磷酸钙(ACP),而在胆结石中磷酸钙通常以羟基磷灰石的形式出现.利用谱学方法研究了ACP与胆盐的作用.结果表明,胆盐以胶团的形式与ACP作用,在溶液中形成复合胶团,使其溶解度增加.不同类型胆盐与ACP的作用能力不同:脱氧胆酸钠(NaDC) > 牛磺胆酸钠(NaTC) > 胆酸钠(NaC).胆盐与ACP中结合钙的亲和能力大于结合钙的亲和能力,使ACP在胆汁的环境下容易转化为羟基磷灰石.  相似文献   

3.
在金属离子-脱氧胆酸-胆红素扩散体系进行了周期沉淀的生长实验,得到了胆红素钙产生的周期沉淀图形.研究了胆红素、脱氧胆酸、Cu2+和Ca2+的相互作用以及它们对周期沉淀图形生长规律的影响,发现脱氧胆酸和胆红素会以复合胶团的形式在凝胶中进行扩散和反应,Ca2+的作用会使胆红素从胶团中分离出来并产生胆红素钙沉淀;Cu2+的作用则会使脱氧胆酸从胶团中分离出来产生脱氧胆酸铜沉淀;复合胶团的反应和扩散速度较慢,其生成周期沉淀的速度也很慢(约6个月,该结果与胆结石的情况较符合);铜离子的作用会使复合胶团加速分解,从而也加快了图形的生长速度.  相似文献   

4.
本文采用不同的溶剂对溶解前后的胆色素类结石进行了主要元素的控制,同时对特征色素类结石进行了有机元素分析,通过比较溶解前后超微结构和各种元素含量的变化,认为胆红素与金属离子,尤其是钙及其后二阶金属离子,形成了胆色素盐或配位络合物,并与糖蛋白等螯合成了大分子复合物。这是胆色素类结石难溶的主要原因。  相似文献   

5.
The influence of Escherichia coliform (E. coli), especially the proteins it secretes, on the nucleation, growth and aggregation processes of calcium bilirubinate (CaBR) in different mimic systems, such as NaCl aqueous solution and model bile, is studied in this paper. The results show that in NaCl aqueous solution the morphology of calcium bilirubinate (CaBR) changes from amorphous sheet structure to a highly self-organized and highly self-replicated fractal structure that is accumulated by rhombic microcrystals after the addition of E. coli. In model bile with the existence of E. coli, CaBR also forms a fractal structure, but the fractal structure is staghorn-like. Meanwhile, the composition of the prepared CaBRs is nonstoichiometric, and the crystallization is greatly improved with the existence of E. coli. Besides, formation mechanism of CaBRs affected by E. coli is explored, showing that the proteins secreted by E. coli interact with the Ca(2+) ions to provide nucleation sites for CaBRs, and the conformation of the proteins becomes more ordered, resulting in the improvement of the crystalline of CaBRs. On the other hand, the interaction of proteins and the Ca(2+) ions also promote the aggregation state of the CaBRs.  相似文献   

6.
通过浊度分析和激光光散射光谱研究了二价金属离子(Ca2+、Cu2+和Mn2+)对蛋黄卵磷脂(EYPC)聚集态的影响.结果表明,自由的二价金属离子对EYPC囊泡有破坏作用,并使EYPC囊泡发生相转变,形成胶束;而与牛磺胆酸钠(TC)结合的二价金属离子使EYPC囊泡半径减小,但不破坏EYPC囊泡.  相似文献   

7.
Proteins may play an important role in the formation of gallstones, but their secondary structure remains unclear in gallstones. In this paper, the insoluble materials of human pigment gallstones dissolved with chloroform, ethanol, ether and hydrochloric acid were studied by Fourier transform infrared spectroscopy. The results show that the insoluble materials of gallstones are mainly composed of bilirubinate salts and proteins. The secondary structure of proteins in pigment gallstones may contain more -helix.  相似文献   

8.
Direct dissolution agents of calcium bilirubinate gallstones were prepared by dissolving chelating agents in aqueous solutions of sodium carbonate containing polar solvent. Dissolution experiments on a calcium bilirubinate disk as a model of a gallstone were performed using a static disk method.

From the amounts dissolved in an hour using dissolution agents with various composition, the most effective conditions for dissolving calcium bilirubinate were determined as follows: (1) the higher the pH of the dissolution agent, the more calcium bilirubinate was dissolved. Thus, pH 8.4 was chosen as the best pH condition within the range of harmless usage to the human body in vivo in limited amount; (2) a combination of ethylenediaminetetraacetic acid (EDTA) as chelating agent for calcium and 1,3-dimethyl-2-imidazolidinone (DMI) as polar solvent; (3) in the mixed system of EDTA and DMI, the most effective concentrations were about 4 wt.% EDTA and about 30 wt.% DMI.

The dissolution agent satisfying the above conditions gave a dissolved amount of about 70 mg dl−1 in 1 h. This amount was considerably higher than those using DMI and EDTA independently. This suggests that dissolution is due to cooperation between EDTA and DMI.  相似文献   


9.
胆汁酸盐对胆红素钙沉淀过程的影响   总被引:1,自引:0,他引:1  
研究了六种人胆汁主要胆汁酸盐对胆红素钙沉淀形成过程的影响。用曲线拟合法处理数据取得热力学及动力学参数。结果表明,六种胆汁酸盐都表现动力学和热力学抑制,而且抑制作用有浓度依赖关系。在一定条件下出现诱导期。虽然不同胆汁酸盐的作用结果相似,但在相同条件下,二羟基胆汁酸和三羟基胆汁酸影响程度不同。  相似文献   

10.
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   

11.
研究了1-羟乙基二磷酸二钠(EHDP)在有,无胆酸钠(CA)存在下,对胆红素(BL)与钙离子反应生成胆红素钙结晶过程的影响。实验结果表明,EHDP对胆红素钙结晶的形成有抑制作用,而胆酸钠的存在加强了这一作用。  相似文献   

12.
水相模拟体系中胆红素钙的合成与表征   总被引:1,自引:1,他引:0  
以水溶液作为生物模拟体系,在不同反应摩尔比条件下,合成了一系列胆红素钙,利用中、远红外光谱,多晶X射线粉末衍射谱,电感耦合等离子体发射光谱等对合成的胆红素钙进行了表征.结果表明:胆红素钙的组成在Ca(C33H34N4O6)和Ca2.4(C33H32N4O6)(H2O)0.06之间变化,具有非化学计量性质,显示了与生物矿化产物相类似的特征.不同的胆红素钙其配位情况有所不同,并且钙含量较高时形成的胆红素钙有较好的结晶态.  相似文献   

13.
在胆酸盐介质中用氨羧配位剂溶解胆红素钙的动力学研究   总被引:1,自引:0,他引:1  
以胆红素及其钙盐为主要成分的色素型胆结石病在国内为常见病,多年来曾研究用钙配位剂溶石的可能性,但效果不明显,主要由于对配位剂溶石机理了解不够。为此本文在模拟胆汁背景条件下,用氨羧配位剂溶解模拟结石的胆红索钙压片进行了动力学研究,其结果有利于阐明胆色素结合配位溶解的机理和决定溶石效果的因素。  相似文献   

14.
Summary The determination of bilirubin in gallstones is carried out by means of several methods, but most frequently by spectrophotometric determination of azobilirubin. We found that most of the methods were not applicable to bilirubin determination in certain types of gallstones. Thus, we developed a simple and suitable method for bilirubin determination applicable to all gallstone specimens. Based on direct spectrophotometric measurements of chloroform solution of bilirubin or gallstone extracts, our method was found to be sensitive enough to determine small amounts as well as high contents of bilirubin in gallstones. Other gallstone components were of no influence on the assay; thus this method proved to be superior to azobilirubin or other assays.  相似文献   

15.
We conducted a time-dependent study of cholesterol (Ch) nucleation to investigate the effect of calcium ions in the moderate supersaturated bile. In taurocholate/lecithin (TC/L) bile at a TC to L ratio of 5.1, the presence of calcium ions enhanced the nucleation rate of Ch. Contrarily, we observed the delayed nucleation of Ch after ~30 days in TC/L bile at a ratio of 2.0, regardless of the calcium ions. From the physical chemistry standpoint, the cholesterol activity (ChAT) is believed to be the driving force for Ch nucleation together with the sufficient nucleation sites. Hence, the micellar formation models along with the binding of TC monomers to calcium ions interpreted the time-dependent results. Furthermore, a quasielastic light–scattering technique detected the formation of micelles and vesicles. In conclusion, the presence of calcium ions in TC/L bile at a high ratio enhances the vesicle appearance for nucleation sites and the high ChAT values for fast nucleation rate of Ch. However, an increase in the L concentration (i.e., low ratio bile) plays a significant role in the prevention of Ch gallstone formation, compared to the decrease in calcium ion concentration.  相似文献   

16.
在反相微乳体系中制备了一系列胆红素配合物,采用红外光谱、ICP-AES和Zeta电位进行了相关的测试与表征。结果表明:铁、镁离子与钙离子共同与胆红素发生了配位作用,且促进了体系中胆红素钙的生成;铁、镁离子的加入导致了胆红素配合物颗粒在水分散体系中的稳定性降低,易聚集。  相似文献   

17.
针对单结合胆红素(monoconjugatedbilirubin,MCB)理化性质极不稳定而造成对其分析、制备的困难性,在Spivak和Trotman方法的基础上建立了一个简单可行的人胆汁结合胆红素(conjugatedbilirubin,CB)高效液相色谱(HPLC)二次洗脱的制备方法,并对方法的可靠性作了论证,得到了MCB较为满意的量与纯度,为进一步探讨MCB的理化性质及其与胆石形成的关系提供了条件。  相似文献   

18.
利用PPP-SCF-CI-DV量子化学程序拟合胆红素以及胆汁酸盐-胆红素水溶液的UV和CD谱, 借以研究胆红素及其与胆汁酸盐复合物的构象性质。发现胆红素与胆汁酸盐作用时, 两个双吡咯生色团的扭角由104°变成112°, 仍保持形成分子内氢键的状态, 其UV及CD谱两个吸收峰间隔的增宽, 主要是胆红素的一侧双吡咯生色团与胆汁酸盐呈疏水性结合的原故; 二羟基和三羟基胆汁酸盐所形成的二元复合物园二色谱的差别, 是胆红素的对映选择性结合造成的。  相似文献   

19.
胆色素结石的结构和难溶组分的分析   总被引:4,自引:0,他引:4  
本实验采用一系列不同的溶剂对溶解前后的胆色素类结石进行了红外光谱观测,并分别用X射线能谱仪和元素分析仪对无机和有机元素进行检测和分析。通过比较溶解前后的红外光谱、无机和有机元素含量的变化,讨论了胆红素与金属离子的结合方式、色素类结石难溶的原因以及可能的成石机制。  相似文献   

20.
The precipitation of three kinds of structures from gallbladder bile of a patient, fractal structure, regular crystal structure, and small disperse granules, was observed in the same sample using Field Emission Gun-Scanning Electron Microscopy (FEG-SEM). The results indicated that there was a transition from a linear equilibrium system to a nonlinear and nonequilibrium system, which was discussed using the theory of entropy. The chemical compositions of these three different kinds of precipitates were determined by energy dispersive X-ray spectroscopy (EDS). This experimental result revealed that Na and Cl played important roles in the formation of the fractal and crystal structures. Besides, the Aggregation-Diffusion-Fractal (ADF) model was used to explain the growth mechanism of the fractal. The article is published in the original.  相似文献   

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