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1.
本文通过用四氧嘧啶复制小白鼠糖尿病模型,以血清中血糖及胰岛素水平为指标,研究了地黄合剂对高糖动物的降血糖作用。结果表明,注射四氧嘧啶前小白鼠血糖为173.47±5.23mg/100ml注射后血糖升高至419.78±22.70mg/100ml(P<0.01),差异有高度显著性。实验组服用地黄合剂后,血糖值从410.25±2739mg/100ml下降至313.51±29.39mg/100ml(P<0.05)差异有显著性。因而认为地黄合剂对于四氧嘧啶性糖尿病有显著的降血糖作用。  相似文献   
2.
NIH3T3 cells transfected with an activated Ha-ras oncogene were treated with L-PHA, the leukoagglutinin from red kidney beans. Cell lines resistant to L-PHA-mediated cytotoxicity were isolated and found to contain reduced levels of L-PHA-binding oligosaccharides. The levels of N-acetylglucosaminyltransferase V, the enzyme responsible for the initiation of the1–6 branch, were reduced in L-PHA-resistant cells. Tumorigenicity in nude mice was unchanged by the change in oligosaccharide expression, but the ability to form lung tumors after intravenous injection was significantly reduced. These results demonstrate that the ability of NIH3T3 cells transfected with an activated Ha-ras oncogene to form lung tumors after intravenous injection into nude mice is reduced in all six L-PHA selected cell lines containing a reduction in1–6 branched Asn-linked oligosaccharides.  相似文献   
3.
The expression of -GlcNAcβ1–6Man-(β1–6) branched oligosaccharides In carcinoma cells has been considered to influence their metastatic potentials. In the present paper, the lectin histochemistry of oral squamous cell carcinomas obtained in biopsy from 34 patients with Phaseolus vulgaris leukoagglutinin (L-PHA), which potentially binds to N-glycosidic carbohydrates with β1–6 linked lactosamin antennae, was studied in order to analyze the relationship between their staining patterns and metastases. The L-PHA-binding oligosaccharides of the carcinomas were expressed on the cell surface in the following patterns: (i) all cells were positive for the staining ('positive'); (ii) some cells were positive but the rest of the carcinoma cells were negative ('weakly positive'); and (iii) all were negative ('negative'). Statistical analysis revealed that the incidence of the metastasis to regional lymph nodes in the 'positive' cases was significantly higher than that in the 'negative' cases. Moreover, the number of the CD14 positive cells including macrophages in the Stroma adjacent to the cardnomas in the 'positive' cases was less than that in the 'negative' or 'weakly positive' cases. The expression of L-PHA-binding oligosaccharides in oral squamous cell carcinoma may be responsible for their metastatic potential to regional lymph nodes, possibly Including their ability to escape macrophage recognition.  相似文献   
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Summary The main dolichol diphosphate-bound oligosaccharides present in primary cultures of both normal and tumor mouse mammary epithelial cells had the same size, yielded the same pattern after acetolysis and paper chromatography, had the same number of mannose residues susceptible to-mannosidase degradation, and were composed of the same monosaccharide residues. This is the first demonstration that normal and tumor mammary cells have dolichol diphosphate-bound oligosaccharides with very similar, if not identical, structures. These compounds are intermediates in the synthesis of asparagine-linked oligosaccharides. On the other hand, normal and tumor cells showed differences in the specific activities of the enzymes involved in the transfer of the distal monosaccharides from the sugar nucleotides to glycoproteins. Sialyl- and fucosyl-transferases were elevated and galactosyl- and N-acetylglucosaminyltransferases were diminished in mammary tumor cells. The intact tumor cells showed an increased fucosylation of glycoproteins of the asparagine-linkage type. Address for reprints: Roberto L. Ceriani, M.D., Ph.D., Bruce Lyon Memorial Research Laboratory, Children's Hospital Medical Center, 51st and Grove Streets, Oakland, CA 94609, USA.  相似文献   
6.
地黄寡糖抗糖尿病药理作用及机制研究回顾   总被引:4,自引:0,他引:4  
现代医学对糖代谢的过程及其调节机制已较明确,并正在走向深入。糖代谢是机体自稳机能(homoostasis)的一个重要方面,Besedovsky等(1977)以神经内分泌系统与免疫系统之间的相互作用及其物质基础为依据,提出了“神经内分泌免疫调节”(neuroenctocrine-immuno-modulation,NIM)网络学说,这个学说的实质是机体神经系统、内分泌系统与免疫系统之间具有共  相似文献   
7.
高效液相色谱法测定地黄中腺苷含量   总被引:9,自引:0,他引:9  
目的:建立地黄中腺苷含量的测定方法,测定不同品种地黄中腺苷的含量。方法:采用高效液相色谱法测定地黄中腺苷含量。以KYWG-C18为固定相,6%乙腈为流动相,检测波长为260nm。结果:腺苷在0.002mg/ml~0.01mg/ml线性良好。回归方程为Y=1.7742×10-4+8.9021×10-7X,r=0.9995。平均回收率为94.1%。RSD=1.86%(n=5)。结论:本法简便、快速、结果可靠。  相似文献   
8.
试管地黄形成过程中形态发生的研究   总被引:3,自引:0,他引:3  
目的 :研究试管地黄形成的形态发生过程 ,比较试管地黄与自然条件下生长的地黄在形态解剖上的异同。方法 :取离体条件下和自然条件下不同阶段形成的地黄块根 ,染色后制成石蜡切片 ,于显微镜下观察。结果与结论 :试管地黄在形态解剖方面与自然条件下生长的地黄具有一致性 ,说明试管地黄在诱导过程中未发生结构上的变化。  相似文献   
9.
Irritable bowel syndrome (IBS) is associated with diverse pathophysiologic mechanisms. These mechanisms include increased abnormal colonic motility or transit, intestinal or colorectal sensation, increased colonic bile acid concentration, and superficial colonic mucosal inflammation, as well as epithelial barrier dysfunction, neurohormonal up-regulation, and activation of secretory processes in the epithelial layer. Novel approaches to treatment include lifestyle modification, changes in diet, probiotics, and pharmacotherapy directed to the motility, sensation, and intraluminal milieu of patients with IBS. Despite recent advances, there is a need for development of new treatments to relieve pain in IBS without deleterious central or other adverse effects.  相似文献   
10.
婴儿期是肠道菌群形成和发展最为关键的时期,作为肠道菌群演替速度较快的重要阶段,稳定的肠道菌群定植对机体健康、免疫系统的建立及完善有着重大且长远的意义。母乳中富含人乳低聚糖(HMOs),能够有效促进婴儿肠道中有益细菌的生长,抑制病原菌的侵袭,改善肠道菌群组成,提高菌种多样性,促进婴儿生长发育。现就HMOs的研究现状及其对婴儿肠道菌群的影响进行综述。  相似文献   
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