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991.
A new acylglycosyl sterol from quisqualis fructus   总被引:1,自引:0,他引:1  
A new acylglycosyl sterol (4) was isolated from the MeOH extract of Quisqualis Fructus together with four known compounds. On the basis of spectroscopic data, their structures were elucidated as clerosterol (1), betulinic acid (2), methylursolate (3), 3-O-[6'-O-(8Z-octadecenoyl)-beta-D-glucopyranosyl]-clerosterol (4) and alpha-xylofuranosyluracil (5).  相似文献   
992.
Introduction and Aims. Cultural and biological particulars existing in East Asian countries are likely to mediate differences in the alcohol consumption experience. Despite this no research to date has directly explored the alcohol free association or expectancy of any East Asian nations. The current research aims to provide a set of South Korean alcohol expectancies. Design and Methods. Two hundred and thirty‐seven South Koreans participated in an alcohol free association test and completed a demographic survey. Results. The results both confirmed and contradicted areas of past alcohol expectancy research. There appears to be differences in associates with high probability of recall and alcohol expectancy, where negative, negative sedating and sedating expectancy categories were not found to be predictors of South Korean drinker level. Discussion and Conclusion. The results suggest that South Koreans have a more even level of negative expectancy across all drinker categories, possibly due to a combination of linguistic, cultural and biological difference found among this population. The results provide a list of South Korean alcohol free association norms for future alcohol research in the region, with the results also underlining the need for alcohol free association tests among East Asian nations.[Mahoney BJ, Graham D, Cottrell D, Kim K‐Y. South Korean alcohol free associations: Negative expectancy not predicting drinks per occasion. Drug Alcohol Rev 2012;31:469–476]  相似文献   
993.
994.
In this study, we developed an expression system of exendin-4, a glucagon-like peptide (GLP-1) analog, using a secretion signal peptide (SP) to facilitate exendin-4 secretion. For delivery of the exendin-4 expression system, high-molecular-weight polyethylenimine (25 kDa, PEI25k), low-molecular-weight polyethylenimine (2 kDa, PEI2k), and polyamidoamine (PAMAM) dendrimers were evaluated as gene carriers to Ins-1 β cells. As a result, PEI25k showed the highest transfection efficiency. For the construction of the exendin-4 expression vector, DNA coding the SP sequence was inserted upstream of the exendin-4 cDNA, resulting in the construction of pβ-SP-Ex-4. Transfection assay showed that the secretion level of exendin-4 increased in the pβ-SP-Ex-4 transfected cells, compared with the pβ-Ex-4 transfected cells. To identify the β-cell protection effect of pβ-SP-Ex-4 delivery, the Ins-1 β cells were transfected with pβ-SP-Ex-4 or pβ-Ex-4 and incubated under normoxia or hypoxia. An MTT assay showed that the pβ-SP-Ex-4 transfected cells had higher β-cell viability than the pβ-Ex-4 transfected cells under hypoxia. In addition, the pβ-SP-Ex-4 transfected cells exhibited lower caspase-3 activity than the pβ-Ex-4 transfected cells. Therefore, PEI25k/pβ-SP-Ex-4 complex may be useful to protect isolated β cells from apoptosis during transplantation.  相似文献   
995.
The hypoglycemic activity of water extracts of fifty six medicinal plants were evaluated in the streptozotocin-induced diabetic mice. Twelve medicinal plants have significantly antidiabetic activity; Mori Radicis Cortex, Kwang Fang Chi Radix, Paeoniae Radix, Eugeniae Flos, Atractylodis Rhizoma, Ophiopogonis Tuber, Rosae multiflorae Fructus, Glycyrrhizae Radix, Tetrapanacis Medulla, Bigno, Forsythiae Fructus and Sophorae Radix.  相似文献   
996.
Three chemotoxins including dimethylnitrosamine (DMN), carbon tetrachloride (CCl4), and thioacetamide (TAA) are commonly used in hepatofibrotic models. We aimed to draw characteristics of histopathology and pro-fibrogenic cytokines including TGF-β, PDGF and CTGF among three models. Rats were divided into six groups and intra-peritoneally injected with DMN (10?mg/kg, for three weeks, three consecutive days weekly), CCl4 (1.6?g/kg, for 10 weeks, twice weekly), TAA (200?mg/kg, for 12 weeks, twice weekly) or their corresponded treatment for each control group. The liver weights were decreased in DMN model, but not other models. Ascites were occurred as 3-, 2-, and 7-rats in DMN, CCl4, and TAA model, respectively. The lipid peroxidation was highest in CCl4 model, serum levels of liver enzymes were increased as similar severity. The hepatofibrotic alterations were remarkable in DMN and TAA model, but not CCl4 as evidenced by the Masson trichrome staining and hydroxyproline. The immunohistochemistry for α-SAM showed that the DMN model was most severely enhanced than other models. On the other hand, hepatic tissue levels of pro-fibrogenic cytokines including TGF-β, PDGF, and CTGF were generally increased in three models, but totally different among models or measurement resources. Especially, serum levels of three cytokines were remarkably increased by CCl4 injection and CTGF levels in both hepatic tissue and serum were highest in CCl4 group. Our results firstly demonstrated comparative study for features of morphological finding and pro-fibrogenic cytokines in serum and hepatic protein levels among three models. Above results would be a helpful reference for hepatofibrotic studies.  相似文献   
997.
An allergic reaction ensues after antigen binds to mast cell or basophil high affinity IgE receptor, Fc epsilonRI, resulting in degranulation of various inflammatory mediators that produce various allergic symptoms. In this study, i) we isolated the active component for the inhibition of mast cell degranulation from the extract of leaves of Castanea crenata and identified it as quercetin; ii) we established the total synthesis procedure of quercetin; iii) using quercetin as positive control, we excavated some lead compounds that possess inhibitory activities for mast cell degranulation by screening the chemical libraries of 1,3-oxazolidine derivatives prepared by solid phase combinatorial chemistry. Some of 1,3-oxazolidine compounds possessing acetyl and 3',4'-dichlorophenyl group displayed strong inhibitory activities on Fc epsilonRI-mediated mast cell degranulation, suggesting that they can be used as lead compounds for the development of anti-allergic agents.  相似文献   
998.
The hepatoprotective activity of lactic acid bacteria (Lactobacillus brevis HY7401, Lactobacillus acidophilus CSG and Bifidobacterium longum HY8001), which inhibited beta-glucuronidase productivity of intestinal microflora, on t-BHP- or CCl4-induced hepatotoxicity of mice were evaluated. These oral administration of lactic acid bacteria lowered beta-glucuronidase production of intestinal microflora as well as Escherichia coli HGU-3. When lactic acid bacteria at a dose of 0.5 or 2 g (wet weight)/kg was orally administered on CCl4-induced liver injury in mice, these bacteria significantly inhibited the increase of plasma alanine transferase and aspartate transferase activities by 17-57% and 57-66% of the CCl4 control group, respectively. These lactic acid bacteria also showed the potent hepatoprotective effect against t-BHP-induced liver injury in mice. The inhibitory effects of these lactic acid bacteria were more potent than that of dimethyl diphenyl bicarboxylate (DDB), which have been used as a commercial hepatoprotective agent. Among these lactic acid bacteria, L. acidophilus CSG exhibited the most potent hepatoprotective effect. Based on these findings, we insist that an inhibitor of beta-glucuronidase production in intestine, such as lactic acid bacteria, may be hepatoprotective.  相似文献   
999.
Traumatic brain injury (TBI) is a major public health problem. Caused by external mechanical forces, a major characteristic of TBI is the shearing of axons across the white matter, which causes structural connectivity disruptions between brain regions. This diffuse injury leads to cognitive deficits, frequently requiring rehabilitation. Heterogeneity is another characteristic of TBI as severity and cognitive sequelae of the disease have a wide variation across patients, posing a big challenge for treatment. Thus, measures assessing network‐wide structural connectivity disruptions in TBI are necessary to quantify injury burden of individuals, which would help in achieving personalized treatment, patient monitoring, and rehabilitation planning. Despite TBI being a disconnectivity syndrome, connectomic assessment of structural disconnectivity has been relatively limited. In this study, we propose a novel connectomic measure that we call network normality score (NNS) to capture the integrity of structural connectivity in TBI patients by leveraging two major characteristics of the disease: diffuseness of axonal injury and heterogeneity of the disease. Over a longitudinal cohort of moderate‐to‐severe TBI patients, we demonstrate that structural network topology of patients is more heterogeneous and significantly different than that of healthy controls at 3 months postinjury, where dissimilarity further increases up to 12 months. We also show that NNS captures injury burden as quantified by posttraumatic amnesia and that alterations in the structural brain network is not related to cognitive recovery. Finally, we compare NNS to major graph theory measures used in TBI literature and demonstrate the superiority of NNS in characterizing the disease.  相似文献   
1000.
C型钠尿肽抑制大鼠胃窦环行肌自发性收缩活动   总被引:3,自引:0,他引:3  
Guo HS  Cui X  Cui YG  Kim SZ  Cho KW  Li ZL  Xu WX 《Acta pharmacologica Sinica》2003,24(10):1021-1026,1062
目的:研究钠尿肽对胃动力的作用及其可能的机制.方法:用四道记录仪记录胃窦环行肌条的自发性收缩活动;利用放射免疫技术测定cGMP的产生量;利用放射自显影技术分析钠尿肽受体在胃内的分布情况.结果:钠尿肽受体在大鼠胃的不同部位均有分布,但在胃窦部最多。ANP、BNP和CNP均能抑制胃窦环行肌条的自发性收缩,其中,CNP的作用尤为明显并呈剂量依赖关系.CNP的这种抑制性作用被鸟苷酸环化酶抑制剂LY83583所削弱,而用cGMF敏感的磷酸酯酶抑制剂zaparinist预处理时CNP的抑制作用明显增加.CNP明显提高胃窦环行肌cGMP的浓度.用非选择性钾通道阻断剂TEA预处理后发现CNP对胃窦环行肌自发性收缩活动的抑制作用明显减弱.结论:钠尿肽受体在大鼠的胃窦分布最多.CNP明显抑制大鼠胃窦环行肌的自发性收缩活动.CNP对大鼠胃窦环行肌自发性收缩活动的抑制效应是通过cGMP途径实现的.钾通道也参与CNP对大鼠胃窦平滑肌的舒张过程。  相似文献   
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