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101.
目的:探讨胃癌合并糖尿病患者术后强化血糖控制的临床疗效及其对预后的影响。方法:根据不同血糖控制方法,将96例胃癌合并糖尿病术后患者分为强化血糖控制组50例(血糖控制在4.4-6.1mol/L)和对照组46例(血糖控制在6.1~11.1mol/L)。监测患者术后1、3、7天的空腹血糖(FBG)、空腹胰岛素定量(FINS)、及C反应蛋白(CRP)水平,并计算胰岛素抵抗指数(HOMA-IR),比较分析两组术后恢复情况及并发症发生情况。结果:术后1、3、7天,强化血糖控制组FBG、lnHOMA-IR及CRP水平均显著低于对照组,差异有统计学意义(P<0.05);术后1天两组间FINS水平差异无统计学意义(P>0.05),而术后3、7天,二者之间差异有统计学意义(P<0.05);强化血糖控制组术后发热时间、排气时间、抗生素使用时间与对照组相比明显缩短,差异有统计学意义(P>0.05);强化血糖控制组术后并发症的发生率2.0%,显著低于对照组13.0%,差异有统计学意义(P<0.05)。结论:强化血糖控制可改善胃癌合并糖尿病患者术后胰岛素抵抗,减轻术后的炎性反应,降低术后并发症,改善患者预后。 相似文献
102.
目的:比较不同血磷水平的维持性血液透析的尿毒症患者的临床表现和实验室指标,探讨其临床意义。方法:选择上海交通大学医学院附属新华医院(崇明)肾内科28例高血磷(SP>1.6mmol/L)的维持性血液透析患者为病例组,30例血磷正常(SP≤1.6mmol/L)维持性血液透析患者为对照组,比较两组患者的原发病组成,年龄,性别,透析龄,皮肤瘙痒发生率,腰背痛发生率,血钙,血碳酸氢根,血红蛋白,红细胞压积,血碱性磷酸酶,肾功能,血浆白蛋白水平及左心室肥厚发生率。结果:病例组与对照组在原发病组成,年龄(43.2±9.8岁vs 40.5±12.2岁),男女性别比例(16/12 vs.17/13),透析龄(32.56±6.71月vs.35.43±5.82月)等方面无显著性差异(P>0.05),有可比性,在血红蛋白(83.22±6.71g/L vs 103.36±5.84g/L),红细胞压积(24.83±1.92%vs.30.76±1.52%),血钙(1.71±0.16mmol/L vs.2.23±0.21 mmol/L),血碳酸氢根(14.2±3.1mmol/L vs 20.6±4.9 mmol/L),血碱性磷酸酶(124.26±16.33U/L vs.61.47±14.91 U/L),皮肤瘙痒发生率(22/28 vs.7/30),腰背痛发生率(19/28 vs.6/30),左心室肥厚发生率(20/28 vs 12/30),有显著性差异(P<0.05),肌酐(956±142mmol/L vs.923±156 mmol/L),尿素氮(23.1±6.3mmol/L vs.24.8±8.9mmol/L),血浆白蛋白(30.5±3.8g/L vs.31.2±2.9g/L),无显著性差异(P>0.05)。结论:伴有高磷血症的维持性血液透析患者与血磷正常的患者相比,血碱性磷酸酶,皮肤瘙痒发生率,腰背痛发生率及左心室肥厚发生率较高,而血钙,血碳酸氢根,血红蛋白及红细胞压积较低,有一定差异。 相似文献
103.
Molecular morphologies and conformation transition of lentinan, a beta-(1-->3)-D-glucan from Lentinus edodes, were studied in aqueous NaOH solution by atomic force microscopy (AFM), viscometry, multiangle laser light scattering, and optical rotation measurements. The results revealed that lentinan exists as triple-helical chains and as single random-coil chains at NaOH concentration lower than 0.05M and higher than 0.08M, respectively. Moreover, the dramatic changes in weight-average molecular weight Mw, radius of gyration [s2](1/2), intrinsic viscosity [eta], as well as specific optical rotation at 589 nm [alpha]589 occurred in a narrow range of NaOH concentration between 0.05 and 0.08M NaOH, indicating that the helix-coil conformation transition of lentinan was carried out more easily than that of native schizophyllan and scleroglucan, and was irreversible. For the first time, we confirmed that the denatured lentinan molecule, which was dissolved in 0.15M NaOH to be disrupted into single coil chains, could be renatured as triple helical chain by dialyzing against abundant water in the regenerated cellulose tube at ambient temperature (15 degrees C). In view of the AFM image, lentinan in aqueous solution exhibited the linear, circular, and branched species of triple helix compared with native linear schizophyllan or scleroglucan. 相似文献
104.
为了研究不同水分条件下组成型根系性状和适应性根系性状的遗传机制,利用由IR64/Azucena发展的双单倍体(DH)群体分析了淹水和干旱条件下水稻幼苗种子根长(SRL)、不定根数(ARN)、总根干重(RW)及其对应的相对参数(干旱和淹水条件下根系性状的比值)的QTLs。淹水与干旱条件下检测到一个共同的种子根长QTL和一个共同的总根干重QTL。同时对前人发表的遗传群体定位的根系性状QTLs进行比较分析,检测到几个共同的根系性状QTLs。对与细胞伸长、分裂相关的候选基因进行了定位,其中4个细胞壁相关的ESTs(OsEXP2,OsEXP4,EXT和Xet)被定位在与不同水分条件下检测出的根系性状QTLs的相同区间。 相似文献
105.
回顾上世纪60年代初,跟随我师王云章教授参与毒菌调查研究时,中国的毒菌仅知80种,中毒类型四种.当时可谓是我国毒菌考察研究的起点,为当今的研究奠定了基础.在王老百岁大寿之际,特将近三十多年收集的标本和有关资料整理并撰写成文,向王老汇报并恭贺生日. 相似文献
106.
XIU GUANG MAO GUANG JIAN ZHU SHUYI ZHANG STEPHEN J. ROSSITER 《Molecular ecology》2010,19(13):2754-2769
The repeated formation and loss of land‐bridges during the Pleistocene have had lasting impacts on population genetic structure. In the tropics, where island populations persisted through multiple glacial cycles, alternating periods of isolation and contact are expected to have driven population and taxonomic divergence. Here, we combine mitochondrial and nuclear sequence data with microsatellites to dissect the impact of Pleistocene climate change on intra‐specific diversification in the horseshoe bat Rhinolophus affinis. This taxon shows considerable morphological and acoustic variation: two parapatric subspecies (himalayanus and macrurus) occur on mainland China and a third (hainanus) on Hainan Island. Our phylogeographic reconstruction and coalescent analyses suggest the island subspecies formed from an ancestral population of himalayanus via two colonization events c. 800 000 years before present. R. a. hainanus then recolonized the mainland, forming macrurus and thus a secondary contact zone with himalayanus. Finally, macrurus recolonized Hainan following the LGM. We found that all three biological events corresponded to known periods of land‐bridge formation. Evidence of introgression was detected between macrurus and both its sister taxa, with geographical proximity rather than length of separation appearing to be the biggest determinant of subsequent genetic exchange. Our study highlights the important role of climate‐mediated sea level changes have had in shaping current processes and patterns of population structure and taxonomic diversification. 相似文献
107.
108.
雷福明毛泽斌 《中国生物化学与分子生物学报》2010,26(1):30-35
HMG盒蛋白1(HMG box-containing protein 1, HBP1)是一种转录抑制因子. HBP1表达上调可抑制肿瘤细胞的增殖和转移,并且在肿瘤细胞中HBP1常常发生丢失或转位,这表明HBP1是一种抑癌基因. HBP1所调节的靶基因无疑将为HBP1的肿瘤抑制机制提供新的线索.本研究通过生物信息学分析发现,在促细胞增殖基因 巨噬细胞移动抑制因子(macrophage migration inhibitory factor, MIF)启动子区域-811 bp至-792 bp发现高亲和力的HBP1反应元件.缺失和突变分析表明,HBP1通过该元件抑制MIF启动子活性.此外,免疫共沉淀研究显示,HBP1在细胞内与该元件结合,并且抑制MIF的转录.功能分析进一步证实,在细胞培养液中加入重组MIF可部分消除HBP1对大肠癌细胞LOVO的抑制作用.这些结果提示,MIF是HBP1的一个靶基因.HBP1通过抑制促细胞增殖基因MIF的表达抑制肿瘤细胞生长. 相似文献
109.
110.
Lentinan (β‐(1→3)‐D ‐glucan) was found to be successfully fractionated by the mixture of dimethyl sulfoxide (DMSO) and lithium chloride (LiCl) as a solvent and acetone as a precipitant. Light scattering and viscosity measurements were made on solutions of fractionated samples in pure DMSO and 0.2M LiCl/DMSO in the range of the molecular weight Mw from 21.7 × 104 to 84.7 × 104. The values of Mw in both solvents were almost the same, but the remarkable difference between the values of intrinsic viscosity [η] demonstrated that the LiCl/DMSO solvent greatly enhances the stiffness of the lentinan backbone. The observed intrinsic viscosity [η] was analyzed by the Yoshizaki‐Nitta‐Yamakawa theory of a worm‐like chain, and the persistence length q and molecular weight per unit contour length ML were determined roughly as 6.0 nm and 890 g nm?1 in 0.2M LiCl/DMSO, and 5.1 nm and 890 g nm?1 in pure DMSO, respectively. This slightly larger persistent length in 0.2M LiCl/DMSO also confirmed the higher stiffness of lentinan enhanced by the LiCl/DMSO solvent. The enhancement of the chain stiffness was ascribed to the electrostatic repulsion because of the hydrogen bonding of the hydroxyl protons of lentinan with the chloride ion, which is in turn associated with the Li+(DMSO)n macrocation complex. © 2012 Wiley Periodicals, Inc. Biopolymers 97: 840–845, 2012. 相似文献