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排序方式: 共有195条查询结果,搜索用时 140 毫秒
61.
Relation of beta-casomorphin to apnea in sudden infant death syndrome   总被引:1,自引:0,他引:1  
Sun Z  Zhang Z  Wang X  Cade R  Elmir Z  Fregly M 《Peptides》2003,24(6):937-943
Sudden infant death syndrome (SIDS) is the most common cause of death in infants and its pathogenesis is complex and multifactorial. The aim of this review is to summarize recent novel findings regarding the possible association of beta-casomorphin (beta-CM) to apnea in SIDS, which has not been widely appreciated by pediatricians and scientists. beta-CM is an exogenous bioactive peptide derived from casein, a major protein in milk and milk products, which has opioid activity. Mechanistically, circulation of this peptide into the infant's immature central nervous system might inhibit the respiratory center in the brainstem leading to apnea and death. This paper will review the possible relationship between beta-CM and SIDS in the context of passage of beta-CM through the gastrointestinal tract and the blood-brain barrier (BBB), permeability of the BBB to peptides in infants, and characterization of the casomorphin system in the brain.  相似文献   
62.
Human leukocyte antigen (HLA) system is the most polymorphic region known in the human genome. In the present study, we analyzed for the first time the HLA-A gene polymorphisms defined by the high-resolution typing methods-sequence-based typing (SBT) in 161 Northern Chinese Han people. A total of 74 different HLA-A gene types and 36 alleles were detected. The most frequent alleles were A*110101 (GF=0.2360), A*24020101 (GF=0.1646), and A*020101 (GF=0.1553); followed by A*3303 (GF=0.1180), A*3001 (GF=0.0590),  相似文献   
63.
Tan  Xiaoyan  Sun  Junshe  Xu  Zhangyang  Li  Hengchang  Hu  Jing  Ning  Huijuan  Qin  Zifang  Pei  Haisheng  Sun  Tian  Zhang  Xiuqing 《Bioprocess and biosystems engineering》2018,41(1):135-141
Bioprocess and Biosystems Engineering - Ganoderma lucidum is a traditional Chinese medicine, and its polysaccharides possess diverse and significant pharmacological activities. This study aimed to...  相似文献   
64.

Objectives

To assess the feasibility and acceptability of a randomized controlled trial compared auricular acupressure (AA) on specific acupoints with AA on non-specific acupoints for treating maintenance hemodialysis (MHD) patients with insomnia.

Methods

Sixty three (63) eligible subjects were randomly assigned into either AA group received AA on specific acupoints (n=32), or sham AA (SAA) group received AA on points irrelevant to insomnia treatment (n=31) for eight weeks. All participants were followed up for 12 weeks after treatments. The primary outcome was clinical response at eight weeks after randomization, defined as a reduction of Pittsburgh Sleep Quality Index (PSQI) global score by 3 points and more.

Results

Fifty-eight (58) participants completed the trial and five dropped out. Twenty participants in AA group (62.5%) and ten in SAA group (32.3%) responded to the eight-week interventions (χ2 = 5.77, P = 0.02). PSQI global score declined 3.75 ± 4.36 (95%CI -5.32, -2.18) and 2.26 ± 3.89 (95%CI -3.68, -0.83) in AA group and SAA group respectively. Three participants died during the follow-up period. No evidence supported their deaths were related to the AA intervention. No other adverse event was observed.

Conclusion

Feasibility and logistics of patient recruitment, randomization procedure, blinding approach, interventions application and outcome assessment had been tested in this pilot trial. The preliminary data appeared to show a favorable result on AA treatment. A full-scale trial is warranted.

Trial Registration

Chinese Clinical Trial Registry ChiCTR-TRC-12002272.  相似文献   
65.

Background

Copy number variations (CNVs) represent an important type of genetic variation that deeply impact phenotypic polymorphisms and human diseases. The advent of high-throughput sequencing technologies provides an opportunity to revolutionize the discovery of CNVs and to explore their relationship with diseases. However, most of the existing methods depend on sequencing depth and show instability with low sequence coverage. In this study, using low coverage whole-genome sequencing (LCS) we have developed an effective population-scale CNV calling (PSCC) method.

Methodology/Principal Findings

In our novel method, two-step correction was used to remove biases caused by local GC content and complex genomic characteristics. We chose a binary segmentation method to locate CNV segments and designed combined statistics tests to ensure the stable performance of the false positive control. The simulation data showed that our PSCC method could achieve 99.7%/100% and 98.6%/100% sensitivity and specificity for over 300 kb CNV calling in the condition of LCS (∼2×) and ultra LCS (∼0.2×), respectively. Finally, we applied this novel method to analyze 34 clinical samples with an average of 2× LCS. In the final results, all the 31 pathogenic CNVs identified by aCGH were successfully detected. In addition, the performance comparison revealed that our method had significant advantages over existing methods using ultra LCS.

Conclusions/Significance

Our study showed that PSCC can sensitively and reliably detect CNVs using low coverage or even ultra-low coverage data through population-scale sequencing.  相似文献   
66.
67.
目的 探讨蛋白磷酸酶4(protein phosphatase 4,PP4)在肿瘤坏死因子(tumor necrosis factorα,TNF-α)诱导JNK磷酸化中的作用.方法 TNF-α处理人肝癌细胞HepG2,免疫印迹检测JNK磷酸化水平和PP4表达水平,免疫沉淀结合磷酸酶活性测定法分析PP4活性变化.构建PP4磷酸酶活性缺失突变体 PP4-RL,转染HepG2细胞,经过G418筛选获得稳定表达FLAG-PP4-RL的克隆,进一步观察PP4对TNF-α诱导的JNK磷酸化的影响.结果 TNF-α处理后迅速引起HepG2细胞JNK的磷酸化,在20 min时达到峰值.PP4的表达在TNF-α处理后60 min内没有显著变化,但活性迅速增强,在20 min时达到峰值.在稳定表达FLAG-PP4-RL的HepG2细胞中,TNF-α诱导的JNK磷酸化被PP4-RL阻断.结论 TNF-α通过激活蛋白磷酸酶4调节HepG2细胞中JNK磷酸化.  相似文献   
68.
Circulating adiponectin is associated with both clinical and subclinical cardiovascular disease (CVD). Variants of the adiponectin gene (ADIPOQ) are associated with clinical CVD, but little is known about associations with subclinical CVD. We studied the association of 11 ADIPOQ single-nucleotide polymorphisms (SNPs) with common and internal carotid intima media thickness (cIMT), presence of coronary artery calcification (CAC), and CAC scores (in those with CAC) in 2,847 participants in the Multi-Ethnic Study of Atherosclerosis (MESA). Participants were white (n = 712), African American (n = 712), Chinese (n = 718), and Hispanic (n = 705). All models were adjusted for age, sex, and field site, and stratified by race/ethnic group. African Americans with genotypes AG/GG of rs2241767 had 36% greater (95% confidence interval (CI; 16%, 59%), P = 0.0001) CAC prevalence; they also had a larger common cIMT (P = 0.0043). Also in African Americans, genotypes AG/AA of rs1063537 were associated with a 35% (95% CI (14%, 59%), P = 0.0005) greater CAC prevalence. Hispanics with the AA genotype of rs11711353 had a 37% (95% CI (14%, 66%), P = 0.0011), greater CAC prevalence compared to those with the GG genotype. Additional adjustment for ancestry in African-American and Hispanic participants did not change the results. No single SNP was associated with subclinical CVD phenotypes in Chinese or white participants. There appears to be an association between ADIPOQ SNPs and subclinical CVD in African Americans and Hispanics. Replication as well as assessment of other ADIPOQ SNPs is warranted.  相似文献   
69.
Massively parallel sequencing of DNA molecules in the plasma of pregnant women has been shown to allow accurate and noninvasive prenatal detection of fetal trisomy 21. However, whether the sequencing approach is as accurate for the noninvasive prenatal diagnosis of trisomy 13 and 18 is unclear due to the lack of data from a large sample set. We studied 392 pregnancies, among which 25 involved a trisomy 13 fetus and 37 involved a trisomy 18 fetus, by massively parallel sequencing. By using our previously reported standard z-score approach, we demonstrated that this approach could identify 36.0% and 73.0% of trisomy 13 and 18 at specificities of 92.4% and 97.2%, respectively. We aimed to improve the detection of trisomy 13 and 18 by using a non-repeat-masked reference human genome instead of a repeat-masked one to increase the number of aligned sequence reads for each sample. We then applied a bioinformatics approach to correct GC content bias in the sequencing data. With these measures, we detected all (25 out of 25) trisomy 13 fetuses at a specificity of 98.9% (261 out of 264 non-trisomy 13 cases), and 91.9% (34 out of 37) of the trisomy 18 fetuses at 98.0% specificity (247 out of 252 non-trisomy 18 cases). These data indicate that with appropriate bioinformatics analysis, noninvasive prenatal diagnosis of trisomy 13 and trisomy 18 by maternal plasma DNA sequencing is achievable.  相似文献   
70.
Yang X  Xue R  Shen C  Li S  Gao C  Wang Q  Zhao X 《Journal of bacteriology》2011,193(18):5032-5033
The genus Rhodococcus has proved to be a promising option for the cleanup of polluted sites and application of a microbial biocatalyst. Rhodococcus sp. strain R04, isolated from oil-contaminated soil, can biodegrade polychlorinated biphenyls. Here we report the draft genome sequence of Rhodococcus sp. strain R04, which could be used to predict genes for xenobiotic biodegradation and provide important insights into the applications of this strain.  相似文献   
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