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How to design clinical trials for medical devices is a problem plaguing the industry today. As there are many differences in clinical trials of medical devices and drugs. This paper describes the differences of the two points from the perspectivs of defi-nition of medical devices and drugs, scope, phasing, subjects and design of clinical trials in details, aiming to help the related personnel make scientific decisions while conduct-ing clinical trial design for medical devices.
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甲型H1N1流感与严重急性呼吸综合征和人禽流感的异同
2009年4月初开始在墨西哥和美国暴发的猪流感病毒H1N1(swine-origin influenza A virus,S-OIV)流感,后经世界卫生组织(WHO)更名为"甲型H1N1流感病毒",这种流感病毒迅速蔓延全球,再一次考验世界,暴发新流行性疾病的威胁依然存在.
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单(双)侧髁突骨折与合并颌骨骨折的治疗原则
髁突骨折是下颌骨骨折的常见类型,约占下颌骨骨折的1/3~([1-6]).髁突骨折分类按照1999年荷兰格罗宁根国际共识会议的建议可以简单分为囊内(髁头)骨折、髁颈骨折和髁突下骨折三种~([7]).其中囊内骨折包含骨折线贯穿囊内外的类型~([8-9]).
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精神医学中的生物统计学(6):对观察性研究治疗效果的估计
In randomized treatment studies the randomization of subjects to the different treatment conditions ensures that the treatment groups are comparable in their baseline characteristics-measured or unmeasured-so we can confidently attribute differences in treatment outcomes to the assigned treatments.In contrast,subjects in observational studies are not randomly assigned to the treatment groups so differences in treatment outcomes could be due to differences in baseline characteristics between the treatment groups.For example,if we wished to compare the outcome of high-intensity treatment for depression (i.e.,many visits in the prior 12 months) versus the outcome of low-intensity treatment for depression (i.e.,few visits in the prior 12 months) and included subjects from both primary care and specialty mental health clinics,any observed differences in the outcomes for low-intensity and high-intensity treatment could be due to differences in the proportions of subjects that were treated in the two types of clinics.When the treatments being compared (e.g.,low versus high intensity of care) and other factors that can affect the outcome (e.g.,type of clinic or patient characteristics) are associated with each other,there is confounding.
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erbB4和PTEN在皮肤鳞状细胞癌组织中的表达
目的 观察并探讨erbB4和FFEN在皮肤鳞状细胞癌(鳞癌)组织中的蛋白表达及其临床意义.方法 采用免疫组化Elivision法,检测52例皮肤鳞癌(其中11例伴有淋巴结转移,41例无转移)、10例正常人皮肤标本中erbB4和VIEN蛋白表达.结果 皮肤鳞癌组中39例erbB4蛋白呈阳性表达,阳性率为75%;对照组中仅1例阳性表达,两组阳性率比较,x2=12.77,P<0.01;皮肤鳞癌患者中在有淋巴结转移组erbB4蛋白阳性表达率(100%)明显高于无淋巴结转移组(68.29%),两组阳性率比较,P<0.05.PTEN蛋白在皮肤鳞癌组中25例阳性表达,阳性率为48.08%,对照组10例均为阳性表达,两组阳性率比较,x2=9.20,P<0.01;在鳞癌高分化组及中低分化组中的阳性率分别为78.57%、36.84%,两组差异有统计学意义(P<0.05);有淋巴结转移组PTEN阳性率(9.09%)明显低于无转移组(58.54%)(P<0.01).皮肤鳞癌erbB4蛋白与PTEN蛋白表达呈负相关(r=-0.42,P<0.01).结论 erbB4与PTEN可能参与了皮肤鳞癌的发生、恶性进展及转移.
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0.1%他克莫司软膏不同疗程治疗面部糖皮质激素依赖性皮炎的临床观察
目的 观察0.1%他克莫司软膏不同疗程治疗面部糖皮质激素依赖性皮炎的临床疗效、安全性以及治疗结束后的病情反跳情况.方法 将104例面部糖皮质激素依赖性皮炎患者随机分为3组,均给予0.1%他克莫司软膏外涂,每日2次,疗程分别为4周、8周、16周,比较3组的疗效.疗程结束后4周随访比较3组的反跳情况.结果 共90例患者完成临床研究,其中疗程4周组32例、疗程8周组29例、疗程16周组29例,总有效率分别为75.00%、82.76%及86.21%,3组间有效率差异无统计学意义.3组的反跳率分别为46.88%、41.38%及20.69%,疗程16周组与疗程4周组、疗程8周组比较,差异均有统计学意义;疗程4周组与疗程8周组比较,差异无统计学意义.31.73%患者局部有刺激反应,均发生在治疗第1周.结论 0.1%他克莫司软膏治疗面部糖皮质激素依赖性皮炎安全、有效,疗程延长,总有效率上升不明显,疗程4周即能获得明显而稳定的疗效.但疗程越长,治疗结束后的反跳率越低.
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结核分枝杆菌差异区基因功能研究及其应用进展
结核病(tuberculosis,TB)是由结核分枝杆菌(Mycobacterium tuberculosis,MTB)引起的一种慢性传染性疾病.目前,全世界大约有1/3的人感染,每年约有900万的新增病例和约200万的死亡病例[1].通过基因组比对发现,结核分枝杆菌基因组中的一些片段在牛分枝杆菌或卡介苗(Bacillus Calmette Guerin,BCG)基因组中缺失,这些缺失片段被称为差异区域(region of differences,RD).研究表明,RD区基因与结核分枝杆菌的毒力密切相关,且这些基因的功能在结核病新疫苗开发及新诊断方法建立中具有重要意义.本文将阐述RD区主要基因功能研究及其应用进展.
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一过性肝密度差异的临床研究
一过性密度差异(Transient Hepatic Parenchy-mal Attenuation Differences,THAD)是指由于各种原因导致肝动脉供血增加,导致肝脏CT动态增强检查时动脉期肝实质局部强化,在门静脉期和平衡期异常强化消退,肝实质密度恢复正常,其实质是肝实质血流灌注异常,磁共振影像中也称作一过性肝信号差异(Transient Hepatic Parenchymal Inten-sity Differences,THID).影像学上可表现为叶多段性、扇形、多形性及弥漫性等四种形态,初由Itai<'[1]>报道,近几年国内外都有所研究.
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肱骨近端骨折反置式人工全肩关节置换术与人工肱骨头置换术的比较
SummaryEarly evidence from two small retrospective cohort studies suggests that reverse shoulder arthroplasty appears similar to hemiarthroplasty for the treatment of proximal humeral fractures in an elderly population.One study found no significant differences for either functional outcomes or range of motion at follow-up.The other study found that Constant scores and range of motion may be better for reverse shoulder arthroplasty.However,only retrospective cohort studies were available,so no definitive conclusions can be drawn from these two small 2项小样本回顾性队列研究的结论认为,反置式人工全肩关节置换术(RSA)与人工肱骨头置换术(HA)在治疗老年性肱骨近端骨折方面疗效相当.其中1项研究发现,随访期间两种方法在功能恢复和活动范围改善方面无明显统计学差异.另1项研究则认为经过RSA治疗的患者,Constant肩部评分结果和肩部活动范围的改善要更好.但是,目前的研究结果来自于回顾性队列研究,因此并不能从中得出比较确切的结论.
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肱骨近端骨折交锁髓内钉与锁定钢板治疗的比较
本研究认为,与锁定钢板相比,交锁髓内钉治疗肱骨近端骨折后并发症的发生率更低。两种治疗方法获得的骨折愈合率相似,对术后肩部功能采用Constant-Murley评分后发现,两种治疗方法所得的肩部评分差异无统计学意义(P>0.05)。此外,需进一步开展大样本、具有严格方法学控制的研究来证实上述结论,以更好地比较交锁髓内钉与锁定钢板治疗肱骨近端骨折的疗效。
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儿童肱骨髁上骨折内外侧交叉克氏针固定与单纯外侧克氏针固定的比较(UPDATE to December 2007 report)
3项小样本随机对照研究显示内外侧交叉克氏针固定与外侧克氏针固定治疗儿童肱骨髁上骨折疗效相当.根据总体研究结果分析,两治疗组间Baumann角和提携角的丢失、关节活动度、功能障碍、医源性神经损伤及感染的发生率等监测指标差异均无统计学意义.虽然感染(其中2项研究)和尺神经损伤(其中1项研究)在内外侧克氏针固定组更为常见,但是差异并无统计学意义.因此,为明确两种治疗方法的远期有效性和安全性,还需开展大样本随机对照研究,并进一步增加病例的随访时间.
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吸烟对胫骨骨折预后的影响
SummaryEvidence from five cohort studies suggest that smoking is associated with higher rates of delayed and nonunion, longer time to union, and greater requirement for sec-ondary surgery to stimulate union following tibia fracture. Smokers also tended to have higher rates of complication (eg, flap failure and infection), but none of the reported differences in serious complications achieved statistical significance. Discrepancies in follow-up rates for smokers compared with nonsmokers should be considered when interpreting results, as should differences in criteria for ascertainment of union.