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排序方式: 共有3633条查询结果,搜索用时 31 毫秒
1.
Jianhui Su Chaoyang Ma Chengxiang Liu Chuanzhong Gao Rongjing Nie 《International journal of food sciences and nutrition》2016,67(1):20-28
This study investigated the hypocholesterolaemic effects of bitter melon aqueous extracts (BMAE) in vitro, the inhibitory effects of BMAE on pancreatic cholesterol esterase (CEase) and incorporation of cholesterol into micelles were investigated. BMAE decreased the in vitro micellar solubility of cholesterol in a dose-dependent manner. The conformation of CEase was investigated by means of circular dichroism (CD) and fluorescence. The result revealed the decrease of α-helix contents, increase of β-sheet and exposure of aromatic amino acid residuals. The incorporation of cholesterol into micelles was inhibited by BMAE. A complex was observed by transmission electron microscopy (TEM), which indicated interaction between cholesterol and BMAE. The result revealed that BMAE can play a role in decreased intestinal cholesterol absorption via inhibition of CEase, and of micelle formation. 相似文献
2.
利用空间频域成像技术搭建的成像系统检测多种皮肤病组织的光学参数和生理参数信息,并对比分析讨论不同类型的皮肤病与光学参数、生理参数之间的关系。实验结果表明,病变皮肤组织与正常皮肤组织之间在光学参数、生理参数上存在较大差异,这将为临床医生对皮肤病诊治提供一种新颖、可靠、科学的评估方法。 相似文献
3.
The objective of this study was to investigate the absorption behavior of chikusetsusaponin IVa (CHS‐IVa) in the rat intestine using single‐pass intestinal perfusion (SPIP) and to classify CHS‐IVa into the biopharmaceutics classification system (BCS). The equilibrium solubility of CHS‐IVa was determined by the shaker method. The absorption mechanism of CHS‐IVa in the intestine was studied by comparing the Peff of different concentrations of CHS‐IVa. The intestinal site dependence of CHS‐IVa absorption was studied by comparing the Peff of the same concentration of CHS‐IVa in different intestinal segments. The relationship between CHS‐IVa and intestinal efflux protein was studied by perfusion with an efflux protein inhibitor. The permeability of CHS‐IVa was investigated by comparing the Peff of CHS‐IVa and the reported value. The solubility of CHS‐IVa over the pH range 1.0–7.5 was 14.4 ± 0.29 to 16.9 ± 0.34 mg/ml. The Peff of CHS‐IVa in the duodenum was 1.76 × 10?3 to 2.00 × 10?3 cm/min. The Peff of CHS‐IVa in the jejunum was 1.26 × 10?3 to 1.39 × 10?3 cm/min. The Peff of CHS‐IVa in the ileum was 1.25 × 10?3 to 1.31 × 10?3 cm/min. The Peff of CHS‐IVa in the colon was 1.02 × 10?3 to 1.08 × 10?3 cm/min. There was no statistical difference of the Peff in the four segments at different CHS‐IVa concentrations. The Peff of CHS‐IVa (0.07, 0.7 and 7.0 mg/ml) were all notably smaller than the reported Peff (3.00 × 10?3 cm/min) in the jejunum. The Peff of CHS‐IVa was not influenced by verapamil (P‐gp inhibitor), indomethacin (MRP inhibitor) and pantoprazole (BCRP inhibitor). CHS‐IVa was classified as high solubility, low permeability and BCS III. The main absorptive tracts were the upper intestinal tracts and the rank order of intestinal permeability was duodenum > jejunum ≈ ileum > colon. The transport mechanism of CHS‐IVa in all intestinal segments might be primarily passive transport. CHS‐IVa was not a substrate of P‐gp, MRP and BCRP. 相似文献
4.
目的 分析H型高血压患者的舌面诊图像颜色参数特征,探讨H型高血压患者的舌诊、面诊变化规律。方法 运用上海中医药大学自行研制的Smart TCM-1型中医舌面一体仪,采集高血压患者舌面诊图像,提取特征参数,分析健康对照组、H型高血压组与非H型高血压组患者舌面颜色参数特征。结果 ①在舌色各项参数中,H型高血压组舌尖部R值、B值、V值均显著小于健康对照组(P < 0.01);非H型高血压组舌尖部B值显著小于健康对照组(P < 0.01),S值较健康对照组显著增大(P < 0.05);H型高血压组舌尖部R、V值均明显小于非H型高血压组(P < 0.05)。在舌苔各项参数中,H型高血压组舌中H值、V值均明显小于健康对照组(P < 0.05);非H型高血压组舌中V值、舌右V值均显著小于健康对照组(P < 0.01);H型高血压组舌中H值明显小于非H型高血压组(P < 0.05),右侧舌苔S值明显大于非H型高血压组(P < 0.05)。②H型高血压组面色参数鼻G值、下颌G值、口唇R值、口唇V值均明显小于健康对照组(P < 0.05);非H型高血压组前额H值、目眶H值、脸颊H值、鼻H值、下颌H值、整体H值均明显大于健康对照组(P < 0.05);H型高血压组前额H值、目眶G值、目眶H值、脸颊H值、鼻G值、鼻H值、下颌R值、下颌G值、下颌H值、下颌V值、口唇R值、口唇G值、口唇V值、整体R值、整体G值、整体H值、整体V值均明显小于非H型高血压组(P < 0.05)。结论 H型高血压患者苔色偏黄,以舌中部为主,且舌右侧黄苔积聚较明显;H型高血压患者面色为黄中带红,口唇、下颌部更为晦暗。H型高血压患者的舌、面诊特征参数的变化,与高血压病阳亢湿盛病机相符。 相似文献
5.
Rik C. Schoemaker Joop M. A. van Gerven Adam F. Cohen 《Journal of pharmacokinetics and pharmacodynamics》1998,26(5):581-593
The most widely applied model relating drug concentrations to effects is the Emax
model. In practice, concentration–effect relationships often deviate from a simple linear relationship but without reaching a clear maximum because a further increase in concentration might be associated with unacceptable or distorting side effects. The parameters for the Emax
model can only be estimated with reasonable precision if the curve shows sign of reaching a maximum, otherwise both EC50
and Emax
estimates may be extremely imprecise. This paper provides a solution by introducing a new parameter (S0
) equal to Emax/EC50
that can be used to characterize potency adequately even if there are no signs of a clear maximum. Simulations are presented to investigate the nature of the new parameter and published examples are used as illustration. 相似文献
6.
良性前列腺增生中医证型与尿动力学参数相关性研究 总被引:1,自引:0,他引:1
目的:探讨良性前列腺增生(BPH)中医证型与尿动力学参数的相关性。方法:152例BPH患者,中医辨证分为肾阴不足、肾阳虚弱、瘀阻水道、脾气虚弱、肺热气郁、湿热下注、痰浊郁结七型,均进行尿动力学检查。结果:152例BPH患者中,肾阳虚弱型71例(46.71%),瘀阻水道型40例(26.31%),肾阴不足型14例(9.21%)。膀胱出口梗阻为III~VI度肾阳虚弱型有58例,瘀阻水道型有38例,其中严重梗阻(V~VI)26例。膀胱逼尿肌收缩功能极弱中(n=12),肾阳虚弱型4例,占33.33%(4/12),瘀阻水道型7例,占58.33%(7/12);膀胱逼尿肌收缩功能弱者中(n=48),肾阳虚弱型为27例,占56.25%(27/48),瘀阻水道型17例,占35.42%(17/48)。结论:BPH中医各辨证分型与膀胱出口梗阻和膀胱逼尿肌收缩力有一定的相关性,从而为中医证型的量化和客观化提供相应的证据。 相似文献
7.
[目的]应用固体滴定技术监测羟基磷灰石(Hydroxyaptite,HA)的溶解平衡过程,观察组织液生理浓度CO2对羟基磷灰石溶解度的影响.[方法]在恒温水浴系统中以HA为固体滴定物.测试液为KCl溶液(0.1 mol/L),并引入恒定分压的CO2(占空气体积比为3.5%±0.1%).半导体二极管激光为发射光源,散射光源探测器用于监测HA的溶解平衡过程并判断超越溶解平衡点所出现的沉淀(合共17次滴定终点).固体滴定总量用于代表溶解度等温线上的数据点.[结果]引入恒定分压CO2后测定的HA在KCl溶液中的溶解度高于其在KCl溶液中所得50倍以上.[结论]固体滴定技术利于监测HA的溶解平衡过程.溶液体系中CO2增加HA的溶解度.推测该现象与CO2-3形成的复合物密切相关. 相似文献
8.
P. K. C. Wang 《Optimal control applications & methods.》1995,16(5):305-320
The problem of controlling the temperature distribution in a solid cylinder whose length varies with time and with one end in contact with a constant temperature medium is considered. This problem is motivated from that of controlling the temperature and thermal gradient inside a crystal pulled from a melt by the Czochralski method. Boundary feedback controls are derived by considering the time rate of change of a cost functional involving the deviations of both the solid temperature and its gradient from their desired values. The derived feedback controls consist of spatially distributed proportional-plus-rate and lag compensators and a non-linear feedback control involving the temperature gradient at the cylinder surface and the velocity of the spatial domain boundary. The resulting feedback-controlled system has the property that the cost functional along any motion decreases monotonically to zero with time. A numerical scheme for solving the partial differential equation of the feedback-controlled system is proposed. Typical numerical results on the dynamic behaviour of the feedback-controlled system obtained by means of the proposed scheme are presented. 相似文献
9.
Cylindrical matrices were prepared by compression either of polyvinyl alcohol 100000 or mixtures of the excipient and a drug (sodium salicylate or theophylline). To modify the cylindrical shape, a hole was bored in the centre of the flat surface through both sides of the matrices. Different swellable systems were obtained applying an impermeable coating to one, two or three surfaces of the perforated matrices. The swelling of the perforated matrices was modified according to the number and the position of the coated surfaces (selective coating) and the loaded drug. Pseudo-zero order kinetics were obtained when the interior hole was the only uncoated surface. 相似文献
10.
Minzhong Yu Lezheng Wu Dezheng Wu 《Documenta ophthalmologica. Advances in ophthalmology》1990,76(1):37-46
The visual pursuit test is a method that collects and analyzes the characteristics of pursuit eye movements and examines the function of the eye movement system. This paper analyzes the model parameters of the smooth pursuit eye movement system in order to explore a method for improving the analysis. The input-output relationship of the smooth pursuit system can be expressed by a quasilinear model. We compute the model parameters (gain, phase, spectral purity, cross covariance) by digital signal processing. Eye movement is recorded by electrooculogram. Both eyes are tested individually. The visual target moves at frequencies of 0.2, 0.4, 0.8, 1.2, and 1.6 Hz. Ranges are gain, 1.01 to 0.70; phase, -0.1 ° to -66 °; spectral purity, 0.97 to 0.70; and cross covariance, 0.99 to 0.26. We tested 40 normal subjects as well as patients with ataxia (8), vertigo (18), and ophthalmoplegia (9). The oculomotor system of normal subjects functions as a linear system in the performance of this test at 0.2 to 0.8 Hz. The spectral purity dropped to about 0.70 at 1.6 Hz. The variability of all measures increases greatly at 1.6 Hz, which indicates that this target motion exceeds the tracking ability of many normal subjects and that the oculomotor system of normal subjects functions as a nonlinear system in this condition. Statistical tests show no significant differences between sex, age, and the two eyes. The model parameters tentatively proved effective in clinical application. 相似文献