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71.
Effect of intragastric pH on control of peptic ulcer bleeding 总被引:31,自引:0,他引:31
Li Y Sha W Nie Y Wu H She Q Dai S Jia L Yu W 《Journal of gastroenterology and hepatology》2000,15(2):148-154
BACKGROUND: We have performed series studies to investigate the effect of intragastric pH on control of peptic ulcer bleeding. In laboratory and animal studies, both platelet aggregation and gastric mucosal bleeding time were shown to be extremely sensitive to different pH levels. Platelet aggregation decreased significantly at pH > or = 6.8 and gastric mucosal bleeding time fell significantly at pH > or = 6.4. In a prospective clinical trial, primed infusions of different dosages of omeprazole (8 or 4 mg/h) after a bolus (40 mg) produced consistently high intragastric pH values in patients with bleeding duodenal ulcer. These results were not significantly different from that obtained from omeprazole 40 mg bolus treatment every 12 h (P > 0.05). However, primed injection with cimetidine (800 mg/12 h) was less effective (P < 0.05). METHODS: In a retrospective analysis, 303 patients with bleeding peptic ulcer who were treated with cimetidine and 326 patients who were treated with omeprazole were compared. RESULTS: The emergency surgery (4.91%) and mortality rates (1.84%) in the omeprazole group were not significantly different (P > 0.05) from those (7.28 and 1.99%) in the cimetidine group. However, the standardized emergency surgery rate of the omeprazole group (3.28%) was significantly lower than that (9.28%) of the cimetidine group (P < 0.05). CONCLUSION: We conclude that increased intragastric pH to at least 6.4 with omeprazole is helpful in controlling peptic ulcer bleeding. Chinese patients require a lower dose of omeprazole than their Western counterparts to control ulcer bleeding. 相似文献
72.
SUMO4 and its role in type 1 diabetes pathogenesis 总被引:1,自引:0,他引:1
Susceptibility to type 1 diabetes (T1D) is determined by interactions of multiple genes with unknown environmental factors. Despite the characterization of over 20 susceptibility regions for T1D, identification of specific genes in these regions is still a formidable challenge. In 2004, we first reported the cloning of a novel, small ubiquitin-like modifier (SUMO) gene, SUMO4, in the IDDM5 interval on chromosome 6q25, and presented strong genetic and functional evidence suggesting that SUMO4 is a T1D susceptibility gene. Subsequent studies have consistently confirmed this association in multiple Asian populations despite controversial observations in Caucasians. In this review, we will update the genetic evidence supporting SUMO4 as a T1D susceptibility gene and discuss the possible explanations for the discrepant associations observed in Caucasians. We will then discuss the mechanisms through which SUMO4 contributes to the pathogenesis of T1D. 相似文献
73.
74.
Yulan Jin Ashok Sharma Shan Bai Colleen Davis Haitao Liu Diane Hopkins Kathy Barriga Marian Rewers Jin-Xiong She 《Diabetes》2014,63(7):2506-2515
There is tremendous scientific and clinical value to further improving the predictive power of autoantibodies because autoantibody-positive (AbP) children have heterogeneous rates of progression to clinical diabetes. This study explored the potential of gene expression profiles as biomarkers for risk stratification among 104 AbP subjects from the Diabetes Autoimmunity Study in the Young (DAISY) using a discovery data set based on microarray and a validation data set based on real-time RT-PCR. The microarray data identified 454 candidate genes with expression levels associated with various type 1 diabetes (T1D) progression rates. RT-PCR analyses of the top-27 candidate genes confirmed 5 genes (BACH2, IGLL3, EIF3A, CDC20, and TXNDC5) associated with differential progression and implicated in lymphocyte activation and function. Multivariate analyses of these five genes in the discovery and validation data sets identified and confirmed four multigene models (BI, ICE, BICE, and BITE, with each letter representing a gene) that consistently stratify high- and low-risk subsets of AbP subjects with hazard ratios >6 (P < 0.01). The results suggest that these genes may be involved in T1D pathogenesis and potentially serve as excellent gene expression biomarkers to predict the risk of progression to clinical diabetes for AbP subjects. 相似文献
75.
对植入材料磨损态的Co-29Cr-5Mo(CCM)和Ti-6Al-4V(Ti64)的细胞毒性进行研究。与固溶态相比,在完全培养液中,通过噻唑蓝(MTT)法研究两种合金在不同浸提浓度、不同浸提时间下的材料浸提液对小鼠成纤维细胞(L929)的毒性及影响机制。扫描电子显微镜(SEM)观察腐蚀前后材料表面的变化,ICP发射光谱仪(ICP-MS)检测CCM和Ti64合金中主要金属离子的释放,电化学工作站(CHI760E)表征两种磨损态合金在完全培养液中的腐蚀情况。MTT实验结果表明:磨损态的两种合金随材料浸提浓度和时间的增大,细胞的相对增殖率(RGR)均减小,其中CCM的RGR由98.36%减小至73.28%,细胞毒性由0级升至2级;Ti64的RGR减小至85.86%,细胞毒性升至1级。ICP-MS结果表明,磨损态合金有害离子的释放量随着浸提时间不断上升,浸提至168 h时,磨损态CCM合金Co和Cr释放量分别高达1 249.7和293.9 μg/L;磨损态Ti64合金Al和V释放量分别为30.7和19.7 μg/L。CCM的Tafel曲线和SEM分析表明,在完全培养液中,CCM表面化学位较高的棱、尖角以及微米级沟壑位置发生了缝隙腐蚀,造成金属离子的释放,并对L929细胞的生长和分裂产生抑制作用。 相似文献
76.
Zhenguo Du Yafei Tang Songbai Zhang Xiaoman She Guobing Lan Arvind Varsani Zifu He 《Archives of virology》2014,159(6):1527-1531
A putative circular single-stranded DNA (ssDNA) virus was recovered from Hypericum japonicum collected in Vietnam. The viral isolate was tentatively named Hypericum japonicum-associated circular DNA virus (HJasCV). HJasCV shares 58.7-65.4% nucleotide sequence identity with Sclerotinia sclerotiorum hypovirulence-associated DNA virus 1 (SsHADV-1) and SsHADV-1-like viruses. Like this group of viruses, the genome of HJasCV (2 200 nt) has two large ORFs, one in the virion-sense and the other in the complementary-sense DNA. The proteins encoded in the virion-sense and complementary-sense ORFs share 39-46 % and 45-67 % amino acid sequence identity with the putative capsid and replication-associated proteins (Reps), respectively, of SsHADV-1 and SsHADV-1-like viruses. The putative Rep of HJasCV contains all of the motifs related to rolling-circle replication. Its 111-bp intergenic region (IR) contains a hairpin structure with a geminivirus-like nonanucleotide sequence, TAATGTTAT, at the apex of the loop. Phylogenetic analysis revealed that HJasCV forms a monophyletic clade with SsHADV-1 and SsHADV-1-like viruses. 相似文献
77.
Yu Rao Yang Qian Yufei Tao Xiao She Yalin Li Zhenming Che Hehe Li Lei Liu 《RSC advances》2019,9(66):38520
The physicochemical and microbial changes, volatile profile, texture and appearance were investigated in three groups of Sichuan pickles differing in oxygen exposure during a 64 day fermentation process. At the beginning, all the Sichuan pickles displayed similar sensory and fermentation characteristics regarding lactic acid bacteria domination, sugar utilization, and lactate accumulation. Soon afterwards, continued exposure allowed premature pellicle formation and typical aerobic deterioration of Sichuan pickle, accompanied by texture destruction and an odorous stench characterized by arenes and aldehydes on the 32nd day. Meanwhile, the facultative anaerobes including Lactobacillus (90 ± 2%), Pediococcus (4.7 ± 0.3%) and Lactococcus (1.2 ± 0.8%) were the dominant genera and probably associated with acetic acid production and arene enrichment under oxygen exposure conditions on the 32nd day. Until the 48th day, intermittent oxygen exposure resulted in pellicle formation and an unpleasant flavor characterized by ketones, esters and S-methyl thioacetate. In comparison, Sichuan pickle without oxygen exposure always maintained a relatively favorable fragrant scent and texture. Besides Lactobacillus, anaerobic genera were the main bacteria in Sichuan pickle under closed conditions and accounted for 50 ± 9% of the total bacteria on the 32nd day. The study indicated the microbial and chemical characteristics of Sichuan pickles during practical production and provided a theoretical guidance for the industrial production of Sichuan pickle.The physicochemical and microbial changes, volatile profile, texture and appearance were investigated in three groups of Sichuan pickles differing in oxygen exposure during a 64 day fermentation process. 相似文献
78.
She Xianliang Qin Saimei Jing Boping Jin Xueyan Sun Xun Lan Xiaoli An Rui 《Molecular imaging and biology》2020,22(4):1043-1053
Molecular Imaging and Biology - The aim of this study was to perform radiotheranostics with radioiodinated monoclonal antibodies (mAbs) for targeting cancer stem cells (CSCs) in human colorectal... 相似文献
79.
目的:观察迷你临床演练评估(Mini-CEX)方法提高毕业第1年新护士规范化培训的效果。方法:采用整群抽样法,以陆军军医大学新桥医院2017年入职的新护士91名为对照组,2018年入职的新护士120名为试验组。对照组采用常规培训方法。试验组在此基础上,将常规教学查房和操作训练改为每月1次Mini-CEX方法下的临床护理核心能力训练和临床护理操作技能培训,连续12次。采用配对样本t检验比较试验组第1次和第12次训练的Mini-CEX得分,采用独立样本t检验比较两组新护士理论和操作考核成绩。结果:试验组第12次的临床护理核心能力训练和临床护理操作技能训练的Mini-CEX得分分别为(6.27±0.46)、(6.73±1.10)分,均高于第1次得分,差异有统计学意义(t值分别为-8.48、-7.64;P<0.01);试验组新护士在1年规范化培训中,科室理论考核和操作考核成绩分别为(87.70±11.32)、(92.90±8.22)分,院级理论考核和操作考核成绩分别为(85.50±11.83)、(89.67±8.99)分,均高于对照组,差异有统计学意义(t值分别为-2.71、-2.09、-2.24、-3.22;P<0.05)。结论:Mini-CEX对提高毕业第1年新护士培训效果作用显著。 相似文献
80.
Regino P. Gonzlez-Peralta Keping Qian Jan Y. She Gary L. Davis Tomoyoshi Ohno Masashi Mizokami Johnson Y.N. Lau 《Journal of medical virology》1996,49(3):242-247
To determine the clinical significance of viral quasispecies heterogeneity, 59 patients with chronic hepatitis C were studied using single-stranded conformational polymorphism (SSCP) analysis of the HCV E2 hypervariable region 1 (HVR1); of these, 48 were subsequently treated with interferon-α. The SSCP method was validated using clones of known nucleotide sequence. HVR1 was amplified in 54 of 59 (92%) patients. The median number of SSCP bands per sample was 6 (range: 2–12). Increased quasispecies heterogeneity correlated with the estimated duration of HCV infection (P < 0.05), parenteral-acquired HCV infection (vs. sporadic, P < 0.05), serum HCV RNA levels (P < 0.05), and HCV genotype 1 infection (P < 0.05), but not with age, serum AST, ALT, or Knodell score. Patients who had complete and sustained response to interferon-α (n = 11) had lower pre-treatment quasispecies heterogeneity compared to patients who had complete response with relapse (n = 18, P < 0.05) or no complete response (n = 16, P < 0.01). However, multivariate analysis revealed that HCV viremia was a stronger predictor of response to interferon-α. These findings indicate that the estimated duration of HCV carriage, serum HCV RNA levels, and HCV type 1 are important determinants for the evolution of HCV quasispecies heterogeneity; and that increased HCV quasispecies heterogeneity is another marker associated with a poor subsequent response to interferon-α. © 1996 Wiley-Liss, Inc. 相似文献