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41.
目的:通过三维运动捕捉与分析系统,采集与分析手法运动数据,归纳肩、肘、膝和踝关节运动特点。方法:由1位施术者在头部、躯干、左右肩峰、肘关节内外侧、腕关节内外侧、前臂外侧、上臂外侧、髂前上棘、髂后上棘、股骨大转子、胫骨结节、内外侧膝、腓骨小头、内外侧踝、足跟、双侧大腿、小腿胫骨外侧以及第1、2、5跖骨头、粘贴光标,对1位受试者完成1次颈椎“骨错缝、筋出槽”治疗的右手手法操作周期,重复5次,对施术者右侧肩、肘、膝和踝关节运动轨迹进行捕捉、记录、计算和分析。结果:手法操作过程中4个关节运动轨迹的趋势一致,其中肘关节的离散度最为明显。肩关节和肘关节的三维活动度明显,而膝关节和踝关节相对较小,然而膝关节的屈伸活动明显大于旋转和侧弯活动。结论:石氏伤科颈椎整复手法的上肢关节灵活性较高,而下肢关节的稳定性是重要保证,其中同侧膝关节通过屈伸活动来辅助上肢发力;红外线三维运动捕捉与分析系统建立的手法模型可以为教学和基础研究提供新的研究思路。  相似文献   
42.
Asthma is a chronic disease for which control is considered the management goal. However, the different methods to measure asthma control, including the Global Initiative for Asthma (GINA) criteria and Asthma Control Test (ACT), can produce conflicting results. This nationwide pediatric study compared both methods in 465 enrolled children (322 males, mean age 11.2 years). Lung function and symptom perception were also evaluated. The results showed fair concordance (k = 0.253) between GINA grading and childhood-ACT (C-ACT). Multivariate analysis revealed an association between the parents' perception of asthma and uncontrolled asthma (odds ratio [OR] = 1.52).These findings highlight the persisting puzzle of asthma control grading in primary care, which could confuse doctors. Therefore, asthma control assessment deserves adequate attention and requires substantial expertise in clinical practice.  相似文献   
43.
44.
Nucleoside/nucleotide analogs (NUC) can lead to rapid reduction in hepatitis B virus (HBV) DNA levels in blood and normalization of alanine aminotransferase levels in many patients. They also provide histological improvement which results in a reduction in liver carcinogenesis. However, it is difficult to completely remove viruses even by NUC and there are some problems such as emergence of resistant strains and hepatitis relapse resulting from discontinuation of treatment. One of the reasons for this is that NUC reduce the HBV DNA level in blood but have almost no effects on the HBV cccDNA level in hepatocyte nuclei, which are the origins of HBV replication, and HBV cccDNA remains for a long period. For treatment with NUC in patients with hepatitis B, it is considered that NUC should not be easily discontinued because discontinuation often results in hepatitis relapse. However, it has not been clearly revealed when and how hepatitis relapses after discontinuation. Although some patients do not experience hepatitis relapse after discontinuation of NUC, or experience only mild relapse and finally achieve a stable condition, it has not been established how to identify such patients efficiently. We performed research to investigate characteristics of the course after discontinuation of treatment and definition of hepatitis relapse and estimate the relapse rate. “Guidelines for avoiding risks resulting from discontinuation of NUCs 2012” is summarized based on the study results. Because the guidelines are written in Japanese, we explain them in English as a review article.  相似文献   
45.
Taking nucleoside/nucleotide analogs is a major antiviral therapy for chronic hepatitis B infection. The problem with this treatment is the selection for drug‐resistant mutants. Currently, identification of genotypic drug resistance is conducted by molecular cloning sequenced by the Sanger method. However, this methodology is complicated and time‐consuming. These limitations can be overcome by deep sequencing technology. Therefore, we performed sequential analysis of the frequency of drug resistance in one individual, who was treated with lamivudine on‐and‐off therapy for 2 years, by deep sequencing. The lamivudine‐resistant mutations at rtL180M and rtM204V and the entecavir‐resistant mutation at rtT184L were detected in the first subject. The lamivudine‐ and entecavir‐resistant strain was still detected in the last subject. However, in the deep sequencing analysis, rt180 of the first subject showed a mixture in 76.9% of the methionine and in 23.1% of the leucine, and rt204 also showed a mixture in 69.0% of the valine and 29.8% of the isoleucine. During the treatment, the ratio of resistant mutations increased. At rt184, the resistant variants were detectable in 58.7% of the sequence, with the replacement of leucine by the wild‐type threonine in the first subject. Gradually, entecavir‐resistant variants increased in 82.3% of the leucine in the last subject. In conclusion, we demonstrated the amino acid substitutions of the serial nucleoside/nucleotide analog resistants. We revealed that drug‐resistant mutants appear unchanged at first glance, but actually there are low‐abundant mutations that may develop drug resistance against nucleoside/nucleotide analogs through the selection of dominant mutations.  相似文献   
46.
47.
目的:了解乙型肝炎病毒(HBV)感染者 HBV 基因型的构成状况及 HBV P 区基因变异的特点。方法对2010年8月~2011年10月送检的740份 HBV 感染者血清,采用 ABI 基因测序仪检测 HBV 耐药位点和基因型,应用 SPSS15.0软件进行统计分析。结果在740例 HBV 感染者中,检出 HBV B 基因型40例(5.41%),C 基因型695例(93.92%),D 基因型5例(0.68%);与拉米夫定、阿德福韦酯和恩替卡韦耐药明确相关的位点突变377例(50.95%),其中195例(51.72%)患者既往有明确的应用核苷(酸)类似物(NA)史,在这195例发生耐药的患者中,B基因型12例,C 基因型183例,两基因型间耐药发生率无明显差异,他们中包括 CHB 患者118例,肝硬化患者77例,主要耐药变异模式为 M204V+L180M、M204I、M204I+L180M 和 A181V,两组间 ALT、HBV DNA 载量和主要耐药变异模式检出率均无统计学差异;HBV DNA 载量是影响 NA 耐药的相关因素(x2=0.496,P〈0.001),但耐药与年龄、性别、疾病严重程度(CHB 或肝硬化)和 ALT 水平无显著性相关;此外,本文还检出多处未知变异位点,如 rt64、rt126、rt178和 rt129等。结论核苷(酸)类似物的使用将伴随病毒变异的发生,其耐药基因变异位点具有一定的特点及规律性,动态监测 HBV DNA 载量对早期发现耐药有一定的价值。  相似文献   
48.
Transient receptor potential melastatin 2 (TRPM2) is a Ca2+-permeable cation channel expressed in immune cells of phagocytic lineage, pancreatic β cells, and brain neurons and is activated under oxidative stress. TRPM2 activity is required for immune cell activation and insulin secretion and is responsible for postischemic neuronal cell death. TRPM2 is opened by binding of ADP ribose (ADPR) to its C-terminal cytosolic nudix-type motif 9 (NUDT9)-homology (NUDT9-H) domain, which, when expressed in isolation, cleaves ADPR into AMP and ribose-5-phosphate. A suggested coupling of this enzymatic activity to channel gating implied a potentially irreversible gating cycle, which is a unique feature of a small group of channel enzymes known to date. The significance of such a coupling lies in the conceptually distinct pharmacologic strategies for modulating the open probability of channels obeying equilibrium versus nonequilibrium gating mechanisms. Here we examine the potential coupling of TRPM2 enzymatic activity to pore gating. Mutation of several residues proposed to enhance or eliminate NUDT9-H catalytic activity all failed to affect channel gating kinetics. An ADPR analog, α-β-methylene-ADPR (AMPCPR), was shown to be entirely resistant to hydrolysis by NUDT9, but nevertheless supported TRPM2 channel gating, albeit with reduced apparent affinity. The rate of channel deactivation was not slowed but, rather, accelerated in AMPCPR. These findings, as well as detailed analyses of steady-state gating kinetics of single channels recorded in the presence of a range of concentrations of ADPR or AMPCPR, identify TRPM2 as a simple ligand-gated channel that obeys an equilibrium gating mechanism uncoupled from its enzymatic activity.Transient receptor potential melastatin 2 (TRPM2) belongs to the TRP protein family and is abundantly expressed in brain neurons, bone marrow, phagocytes, pancreatic β cells, and cardiomyocytes, where it forms Ca2+-permeable nonselective cation channels that open under oxidative stress. On contact with pathogens, phagocytic cells produce reactive oxygen species (ROS); the resulting activation of TRPM2 provides the Ca2+ influx necessary for cell migration and chemokine production (1). In pancreatic β cells, TRPM2 activity contributes to glucose-evoked insulin secretion; TRPM2 knock-out mice show higher resting blood glucose levels and impaired glucose tolerance (2).TRPM2 activity is also linked to several pathologic conditions that lead to apoptosis (3). Reperfusion after ischemia results in ROS generation; consequent Ca2+ influx through TRPM2 causes Ca2+ dysregulation and cell death. Certain neurodegenerative diseases, such as Alzheimer’s disease, also involve oxidative stress and TRPM2 activation. In contrast, a loss-of-function TRPM2 mutation identified in patients with amyotrophic lateral sclerosis and Parkinson''s disease dementia (4), as well as two TRPM2 mutations associated with bipolar disorder (5), suggest loss of TRPM2 activity can also cause disease.Similar to most TRP family ion channels, the TRPM2 channel is a homotetramer, and its transmembrane (TM) architecture resembles that of voltage-gated cation channels (6, 7). In addition to the TM domain and an N-terminal cytosolic domain of unknown function, TRPM2 contains an ∼270-residue C-terminal cytosolic nudix-type motif 9 (NUDT9)-homology (NUDT9-H) domain. The latter shows high (∼50%) sequence homology to the soluble mitochondrial enzyme NUDT9, an active ADP ribose (ADPR) pyrophosphatase (ADPRase) from the Nudix hydrolase family, which splits ADPR into AMP and ribose-5-phosphate (8). TRPM2 channels are coactivated by ADPR binding to NUDT9-H (9) and by Ca2+ binding to unidentified intracellular binding sites (10). ADPR is the key that links TRPM2 activation to oxidative stress; in living cells exposed to ROS, ADPR is released from mitochondria (9). In the past, studying TRPM2 channel gating at steady state has been limited by rapid deactivation of TRPM2 currents in cell-free patches (10). This rundown was recently shown to involve a conformational change of the ion selectivity filter, which could be completely prevented by a pore-loop substitution. This “T5L” TRPM2 variant, which shows no rundown but preserves intact regulation of gating by Ca2+ and ADPR (11), provides an unprecedented opportunity to study TRPM2 gating at steady state.Early studies reported slow (∼0.1 s−1) but detectable ADPRase activity of isolated purified NUDT9-H (8, 12), classifying TRPM2 into the special group of channel-enzymes (“chanzymes”) that includes TRPM6 and TRPM7 (3) and the CFTR cystic fibrosis transmembrane conductance regulator (CFTR) chloride ion channel (13). TRPM2 pore opening/closure happens on the timescale of the reported ADPRase activity (11), which is consistent with coupling between gating and catalytic activity, as demonstrated for CFTR in which pore gating follows an irreversible cycle tightly linked to ATP binding and hydrolysis at conserved cytosolic domains (14).The involvement of TRPM2 in multiple diseases has made it an emerging therapeutic target. Depending on the disease, both inhibition (e.g., stroke, myocardial infarction, Alzheimer’s disease, chronic inflammation, hyperinsulinism) and stimulation (e.g., diabetes, amyotrophic lateral sclerosis, Parkinson''s disease dementia, bipolar disorder) of TRPM2 activity might be useful therapeutically. Because TRP family channels are involved in diverse processes (3), any useful TRPM2 agonists/antagonists will need to be highly selective. This singles out the NUDT9-H domain, the component unique to TRPM2, as the most attractive drug target. The significance of understanding whether ADPRase activity and gating are coupled is that optimal strategies for modulating fractional occupancy of a particular conformational state are profoundly different for equilibrium systems than for nonequilibrium systems. For most ion channels, pore gating is an equilibrium process, and open probability is modulated simply by energetic stabilization of either open (activators) or closed (inhibitors) channel ground states. In contrast, channels that gate by a nonequilibrium cycle are most efficiently accumulated in either open or closed states by manipulating the stability of transition states for rate-limiting irreversible steps (15). The aim of this study was to examine the tightness of coupling between the ADPRase cycle and specific gating transitions in TRPM2.  相似文献   
49.
目的 分析视觉模拟评分法(visual analog scale,VAS)评价腭裂术后腭咽闭合状态的可靠性,为非直观检测腭咽闭合功能声学仪器间接评价腭咽闭合功能提供参考.方法 应用鼻咽纤维镜对唇腭裂修复术后82例患者进行11个语音样本的腭咽闭合状态检查,由3名有多年治疗唇腭裂临床经验的专家在无声状态下对腭咽闭合状态进行分级定性及视觉模拟量表评价,对选取语音样本VAS值与分级定性评价进行Spearman相关分析,对选取语音样本中10个非鼻辅音语音样本按照腭咽闭合程度分级定性评价分类,计算定性评价不同类型腭咽闭合的VAS值范围.结果 定性评价不同类型腭咽闭合状态VAS值明显不同,重度腭咽闭合不全VAS值最小(28.4137),完全性腭咽闭合VAS值最大(96.0568),而且正常值范围相互交叉范围较大,通过VAS值界定腭咽闭合状态有效性>70%.结论 腭咽闭合程度VAS评价能够正确反映腭咽闭合定性评价的结果,VAS值对腭咽闭合形态是可靠的,提出VAS值评价腭咽闭合状态的标准进一步细化了腭咽闭合功能的定性评价.  相似文献   
50.
A systematic review of purine analogs revealed heterogeneity between trials in treatment effects on response and progression free survival, but not survival, perhaps partly due to variations in analytical methods. In addition, combination treatments required evaluation. Therefore, individual patient data were sought for all randomized trials in untreated chronic lymphocytic leukemia which involved a purine analog, but which did not include antibody therapies. Sixteen trials were found, addressing seven comparisons. Eight trials, with 2,753 patients, showed that single agent purine analog improved progression free survival (odds ratio=0.71; 95% confidence interval=0.63-0.79). Heterogeneity remained substantial. Three trials, with 1,403 patients, showed that progression free survival was further improved by the addition of cyclophosphamide (odds ratio=0.54; 0.47-0.62). Fewer data were available on the addition of other drugs to purine analog, and none showed clear benefit. Two trials, with 544 patients, suggested cladribine improved progression free survival compared to fludarabine (odds ratio=0.77; 0.63-0.95). No differences were seen in overall survival for any comparisons. In conclusion, purine analogs, particularly combined with cyclophosphamide, significantly improve progression free survival but not survival. Some groups, such as the elderly, may not see the same benefits and maximizing doses may be important for all treatments, including chlorambucil. Longer follow up, consistent definitions and detailed reporting of trials should be encouraged.  相似文献   
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