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11.
藏汉民族线粒体基因组全序列的比较研究   总被引:1,自引:0,他引:1  
目的 以藏汉民族线粒体基因组全序列为基础,进行Haplogroup构建和系统发生分析,在全序列水平上比较核苷酸的变异,阐释可能的变异机制和蕴含的生物学意义.方法 采用Applied Biosystems 3730DNA自动测序仪分别对40名藏族和50名汉族的标本进行线粒体DNA序列测定,应用phredPhrap 16.0软件进行全序列拼接,并以rCRS(revised Cambridge Reference Sequence)为标准与测定序列进行比对分析;根据MTTO-MAP的标准,通过Network方法进行Haplogroup构建和系统发生的分析,并结合其它方法对产生的数据进行深入解读.结果 数据分析结果显示:在系统发生上,藏汉民族90个线粒体DNA序列归类到13个Haplogroups,除M9以外,其它各Haplogroup出现频率之间比较差异无统计学意义;通过两个民族的线粒体DNA全序列比对,发现21个分布频率有统计学意义的变异位点,其中的5个为新变异位点;另外,对D-Loop区的5个突变位点进行了单倍型构建,90个标本可分为2种Supertype,发现在藏汉民族之间Supertypel和Supertype 2的分布频率均有统计学意义.结论 藏汉民族在种族起源和系统发生上具有较近的母系遗传关系;在全序列有统计学意义的位点究竟是适应性或者中性选择,抑或是一种病理性突变尚需深入的探讨.  相似文献   
12.
Journal of Community Health - The purpose of this study was to evaluate family physicians’ job strain during the Covid-19 pandemic and determine the effective factors. The study was carried...  相似文献   
13.
松质骨中两种纵波的传播特性分析   总被引:2,自引:1,他引:2  
基于松质骨的层状模型,利用Schoenberg理论分析了松质骨中两种纵波(快纵波和慢纵波)的传播特性;并在理论和实验上详细分析了骨小梁方向与传播方向间的夹角对松质骨中快纵波和慢纵波传播特性的影响。分析结果表明,当超声波平行于骨小梁入射时,松质骨中两种纵波都传播,入射角度在60度附近时,松质骨中两种纵波的相速度曲线有一个转折点,入射角度在60度以上,角度越大时,骨髓和骨小梁耦合得越紧,因此阻止了慢纵波的传播,而只有快纵波传播。  相似文献   
14.
RMP-7, a nine-amino acid bradykinin analogue, has been shown in animals to temporarily increase the permeability of the blood brain barrier to small molecules including amphotericin B, when administered intravenously. We sought to evaluate the safety of escalating doses of RMP-7 administered to human volunteers with the acquired immune deficiency syndrome (AIDS). Six HIV antibody-positive adults with CD4+ cell counts <50/mm3 received three increasing doses of RMP-7 on successive days: 30 ng/kg, 100 ng/kg and 300 ng/kg infused over 2, 2 and 10 min, respectively. Adverse experiences were dose-related, mild-moderate in intensity, primarily related to vasodilation and resolved rapidly without sequelae. Mean maximum increases in pulse rate at 30 ng/kg, 100 ng/kg and 300 ng/kg were 4.0, 7.8 and 28.2 beats per min, respectively. The maximum changes in average mean arterial pressure were +7.7, +5.6 and −0.2 mmHg from baseline, respectively. Minor increases in liver enzymes were noted in three patients, all with pre-existing enzyme elevations. Despite the high frequency of both occult and overt cardiovascular abnormalities in advanced HIV infection, RMP-7 is shown to be safe in this group of AIDS patients at all dosage levels tested, with adverse effects similar to previous experience in healthy humans.  相似文献   
15.
Data from the Social Security Administration's 1982 New Beneficiary Survey and Master Beneficiary Record were matched with 1984 data from the Medicare Automated Data Retrieval System to study the effects of self-reported health on subsequent health service usage and survival. Proportionately, more new retired workers who reported poorer health in 1982 were decreased by December 1984. Functionally dependent beneficiaries as determined by the Functional Capacity Limitation Index had death rates four to five times greater than those who reported no limitations. The health status of retired workers who received Social Security benefits before age 65 was no better than beneficiaries 65 or over. Decedents were more likely than survivors to incur Medicare charges, and to have substantially higher median charges--$8,834 compared with $285.  相似文献   
16.
小牛血去蛋白提取物对胃溃疡患者的疗效评价   总被引:2,自引:0,他引:2  
目的:探讨小牛血去蛋白提取物(DCBE)对胃溃疡的治疗作用。方法:选择年龄20~70岁之间,经胃镜检查确诊为活动期胃溃疡的住院患60例。治疗组32例采用静脉滴注DCBE(800mg,qd)和法莫替丁(100mg,bid)治疗;对照组28例采用静脉滴注法莫替丁(100mg,bid)单独治疗。用药2、4wk行胃镜检查,观察自觉缓解症状、时间、愈合率和总有效率。结果:治疗组自觉症状缓解时间明显缩短;给药后2、4wk治疗组及对照组胃镜检查溃疡愈合率分别为78.1%,46.4%及84.4%,71.4%。结论:DCBE能显促进胃溃疡的愈合。  相似文献   
17.
18.
Although emollients can be sufficient to manage mild atopic dermatitis (AD), acute flares resulting in moderate‐to‐severe symptoms require treatment with anti‐inflammatory agents, such as topical corticosteroids (TCs) and topical calcineurin inhibitors (TCIs). This review examines the role of a member of the newest class of TCs, the fourth‐generation compound methylprednisolone aceponate (MPA) in AD management, with reference to the chemical structure, pharmacokinetics, efficacy in AD, safety assessed in preclinical and clinical trials and dosing considerations. MPA has an optimized efficacy/safety profile with minimal local or systemic adverse effects. In addition, it offers the opportunity for once‐daily dosing, which provides benefits in terms of patient compliance with treatment.  相似文献   
19.
Background: Families living with aphasia often have unmet needs despite intervention provided in hospital and rehabilitation environments (Denman, 1998; Michallet, Le Dorze, & Tétreault, 2001). Michallet and colleagues found that families living with aphasia need information and support throughout the care continuum. If needs are unmet during the early stages of rehabilitation they persist, and as families deal with the long term sequelae of aphasia, new needs emerge in relation to communication and role changes. Few recent interventions have addressed the complex needs experienced by caregivers of people with aphasia (e.g., Hinckley & Packard, 2001; Hinckley, Packard, & Bardach, 1995; Pound, Parr, & Duchan, 2001). Aims: This research aimed to identify the critical elements and outcomes of a residential intervention for families living with aphasia. Methods & Procedures: Narrative data were collected from 19 spouses, siblings, and adult children of persons with aphasia who attended a residential intervention over 3 years. Data collected from participants during and following the intervention were triangulated with field notes recorded by 34 students trained in field observation techniques. All narrative data were transcribed, coded, and analysed using procedures described by Luborsky (1994). Outcomes & Results: Data analysis revealed four critical intervention elements: (a) an emotionally and physically safe environment; (b) respite from the demands of caregiving; (c) peer learning; and (d) participation of families with different amounts of time post aphasia onset. Outcomes from the perspective of the participants included: (a) a renewed sense of hope; (b) improved ability to access their social support resources; (c) improved ability of caregivers to monitor their well-being; (d) greater acceptance of the family's altered state; and (e) emergence of a new social support network. Analysis of thematic relationships showed a web of interconnections between all critical elements and outcomes of the intervention. A central intervention element was learning from peers with different levels of caregiving experience. Conclusions: Some aspects of caregiver learning appear to depend on interventions that are structured to maximise reflective learning from peers. Professionals may underestimate the value of such learning in intervention for caregivers of persons with aphasia.  相似文献   
20.

Objectives

This prospective, randomized, double-blind, placebo-controlled study compared the efficacy and safety of amiodarone and sotalol in the prevention of atrial fibrillation (AF) following open heart surgery.

Background

The incidence of supraventricular arrhythmias following open heart surgery ranges from 20% to 40%, with AF being the most common. Both amiodarone and sotalol have been shown to be effective in reducing postoperative arrhythmias, but no direct comparison of these agents has been conducted.

Methods

A total of 160 patients were randomized, of whom 134 underwent coronary artery bypass graft surgery (CABG) alone, 17 underwent CABG and concomitant aortic valve replacement surgery (AVR), 9 underwent AVR only, and 1 patient's surgery was canceled. Patients with signs or symptoms of congestive heart failure (CHF), ejection fraction ≤30%, estimated creatinine clearance <30 mL/min, or serum creatinine ≥2.5 mg/dL were excluded. Patients were randomized to receive either sotalol 80 mg 2 times per day (n = 76) or intravenous amiodarone 15 mg/kg over 24 hours followed by oral amiodarone 200 mg 3 times per day (n = 83). Study drug was started at the time of surgery and continued for 7 days or until discharge, whichever came first.

Results

AF occurred in 17% of patients randomized to amiodarone and 25% of the patients randomized to sotalol (P = .21). However, the duration of AF was significantly shorter in amiodarone-treated patients (169 ± 224 min) compared to sotalol treated patients (487 ± 505 min; P = .04). In a subgroup analysis, the incidence of AF in patients undergoing AVR or CABG with AVR was significantly less with amiodarone (1/15, 7%) compared to sotalol (9/11, 82%) (P < .001). Blood pressure was lower immediately after surgery with amiodarone but comparable to sotalol at 24 hours. Of the hemodynamic indices measured, only stroke volume was significantly lower in patients randomized to sotalol at 24 hours (P = .035).

Conclusions

Amiodarone and sotalol share similar efficacy and safety in reducing postoperative AF. Hemodynamic effects were similar between both drugs at 24 hours, with the exception that stroke volume was lower in sotalol-treated patients. In patients undergoing more complex surgery, postoperative AF occurred more frequently with sotalol than with amiodarone.  相似文献   
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