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41.
人体蠕形螨的生物学研究 总被引:4,自引:0,他引:4
用透明胶带法观察蠕形螨在人体面部的寄生、逸出及其在体外的存活能力。结果表明:毛囊蠕形螨(Demod-exfoliculorum,D.f.)主要以颚体朝向毛囊底部寄生,且常常有多条群居现象,而皮脂蠕形螨,(Demodexbrevis,D.b.)一般为单条独居生活。两种人体蠕形螨昼夜均可主动爬出毛囊口出现在皮肤表面,D.f.以白天1000~1800为逸出高峰;D.b.则以夜间2200~200逸出最多。此外,蠕形螨在体外有较强的活动力和存活力。透明胶带法在人体蠕形螨的流行病学调查和生物学研究方面具有较高的应用价值 相似文献
42.
Teaching psychiatric ethics 总被引:1,自引:0,他引:1
S Bloch 《Medical education》1988,22(6):550-553
In the last decade, we have witnessed a burgeoning of interest in ethical issues amongst psychiatrists. Teaching of the subject, however, remains at a rudimentary stage. Various approaches to such instruction are available, particularly modelling (students observe their experienced counterpart), the case method (examining specific clinical situations which involve a need for ethical decision-making), and the seminar approach (trainees are exposed to a core body of knowledge, mainly theoretical in nature). Faced with these different teaching models, the University of Oxford Department of Psychiatry has opted for a blend of all three approaches, which incorporates two goals: an increase in the trainees' sensitivity to the many intricate moral dilemmas facing the psychiatric profession; and their familiarity with salient concepts in moral philosophy which constitute a basis for ethical reasoning and which have a bearing on clinical practice. The teaching programme comprises the following: a pair of trainees prepares a presentation on an aspect of psychiatric ethics under the supervision of a senior psychiatrist. A moral philosopher assumes the role of discussant of the ethical problems raised by the trainees; this is followed by a general discussion. Topics have included involuntary hospitalization, dual loyalty, suicide, psychiatric diagnosis, and ethical issues in various spheres of psychiatric practice such as sex therapy, psychotherapy and child psychiatry. The approach has worked effectively and proved rewarding to all participants involved. 相似文献
43.
目的 研究异型增生程度不同的口腔白斑和不同分级的鳞癌中谷胱苷肽S转移酶π(GST π)的表达 ,探讨GST π在口腔鳞癌发生发展中的作用。 方法 采用免疫S -P法 ,对 5 4例轻、中、重度异型增生 ,4 7例高、中、低分化的口腔鳞癌 ,7例口腔粘膜上皮单纯增生患者组织进行GST π检测。 结果 口腔粘膜上皮单纯增生组织中未见GST π的表达 ,轻、中、重度异型增生病例中的GST π阳性率分别为4 7.8%、5 2 .9%和 6 4 .2 % ,高于单纯增生组 (P <0 .0 1) ;高分化鳞癌GST π阳性率为 6 4 .7% ,中、低分化鳞癌组分别为 2 8.5 %及 2 2 .2 % ,中、低分化鳞癌组表达均低于高分化鳞癌组及异型增生组 (P <0 .0 5 )。 结论 GST π表达的变化与口腔鳞癌早期的发生发展密切相关 相似文献
44.
腰椎节段形态对峡部、小关节应力及小关节接触力影响的有限元分析 总被引:1,自引:0,他引:1
目的:探讨腰椎形态结构变化对峡部裂性滑脱及小关节退变的作用和意义。方法:采用改良的“非种子区域分割方法”及非平行“最佳切割平面”等一系列新型计算机辅助设计(CAD)方法精确建立包括椎间盘高度、腰椎小关节角、椎间盘前凸角改变的L4~L5活动节段有限元模型;在2700N轴向压缩载荷条件下,分别对各有限元模型的峡部、小关节应力、小关节接触力以及椎间盘负载进行测试。结果:压缩载荷下,腰椎活动节段峡部、小关节等效应力及小关节接触力随椎间盘高度的减小而减小,随小关节角的增大而增加,随椎间盘前凸角的增加而减小。结论:椎间盘高度、腰椎小关节角、椎间盘前凸角等形态结构变化对腰椎节段有限元模型的峡部、小关节应力及小关节接触力有明显的影响。提示腰椎峡部应力性骨折及小关节退变的发生与椎间盘高度、腰椎小关节角、椎间盘前凸角等解剖形态因素有关。 相似文献
45.
用5只猫于左侧颈部食管壁内注入 HRP 溶液,通过 HRP 逆行追踪法研究颈部食管的交感神经支配,结果表明:1.长轴突型交感节前神经元直接分布到食管壁内,其标记细胞位于双侧脊髓的胸1~3节段,以胸2节段最多(占标记细胞总数的66.45%),注射侧占优势。标记细胞主要位于中间带外侧核(约占95.02%),其次为侧索、中介核、前角腹后外侧核。其细胞形态不一,以中小型细胞为主(占标记细胞总数的90.4%)。2.支配颈部食管的交感节后神经元主要位于星状神经节(约占61.99%),余者位于双侧颈前、中和2~5胸交感节内、以小细胞最多。 相似文献
46.
本文提出的“差式氧化数法”特别适用于有机化学反应方程式的平衡。在未平衡方程式之前即可直接求出有机物的氧化还原当量,然后再平衡方程式。较以前先平衡方程式,再间接计算氧化还原当量的方法简便,快速,易掌握。 相似文献
47.
引入PDCA循环规范医疗废物管理 总被引:2,自引:0,他引:2
目的采用PDCA循环法,规范医院医疗废物管理。方法通过计划、实施、检查、处理4个阶段具体实施。结果医疗废物要达到规范化管理,建立有效的组织管理体系,制定切实可行的规章制度是重要保证;加强培训与宣传教育,提高全员管理意识是重要环节;完善医疗废物处置过程中的配套设施是重要基础;制定管理质量标准认真督促检查考核是重要手段。结论PDCA循环法是加强完善医疗废物管理的一种科学的管理方式。 相似文献
48.
本文介绍使用氨气敏电极,采用标准曲线法简便、快速、准确测定血氨的方法。取空腹血1ml,用1M HClO_4沉淀蛋白,以0.1M NH_4Cl—0.6MNa_2SO_4作内充液,碱化后的上清液可在2~3min内测试完毕。40例正常成人血氨的测定结果:■=31.4μmol/L N;S=6.4μmol/L N;■±2S(正常值范围)为18.6~44.2μmol/L N。10份血样的平均回收率为100.4%。该法用血少、简便、快速;结果较稳定、准确,适用于临床检验。 相似文献
49.
Objectives To analyze the relationship between lateral displacement of the mandible and scoliosis.
Methods From April 2002 through July 2003, we examined posteroanterior cephalometric radiographs and chest X-rays from 85 patients
with jaw deformities and a control group of 20 patients with no jaw deformities. To measure the lateral shift of the mandible,
we drew a horizontal baseline (X axis) on the cephalogram connecting the intersection of the external margins of the orbits and the most lateral points of
the greater wings of the sphenoid. A vertical baseline (Y axis) was then marked perpendicular to the X axis, intersecting the ethmoid crista galli. Then, we measured the lateral displacement of the mandibular mentum from the
Y axis. Displacement to the right was designated positive; that to the left was designated negative. Cobb's method was used
to measure scoliosis curves on chest X-rays; the direction of the curve was designated similarly.
Results Of the 85 patients with jaw deformity, 23 (27.1%) had a Cobb angle exceeding 10°. None of the control group had scoliosis
exceeding 10°. No correlation was found between the direction of mandibular displacement and the direction of scoliosis.
Conclusion This study suggests a relationship between jaw deformities and scoliosis, as scoliosis was found in 27.1% of the patients
with a main complaint of jaw deformity. 相似文献
50.
Introduction and Aims. Different self‐report methods tend to produce different estimates of alcohol consumption. The present study compares differences in rates and risk levels based on responses to a modified version of the Daily Drinking Questionnaire (m‐DDQ) and quantity‐frequency (QF) questions. Design and Methods. The sample comprised 2082 university students, 61% of whom were female and 39% male with a mean age of 23.5 years. An email containing an online link to a brief six‐question survey was emailed to students enrolled in participating faculties at the University of Wollongong, Australia. Current drinkers completed m‐DDQ and QF questions about alcohol consumption. Results. QF methods identified significantly lower estimates of consumption (Mean = 9.15, SD = 12.51) compared with m‐DDQ (Mean = 13.06, SD = 14.07). Allocation to risk categories based on the Australian Alcohol Guidelines were conducted for both the m‐DDQ and QF methods. Almost twice as many students were found to be drinking at levels considered risky using the m‐DDQ method compared with QF. In addition, the relative rank order of participants varied significantly between the two methods. Discussion and Conclusions. The m‐DDQ method identified higher rates of drinking and categorised almost twice as many individuals into risky categories of drinking compared with QF. Such variations have major implications for identification of risk groups in health promotion or prevention programs.[Utpala‐Kumar R, Deane FP. Rates of alcohol consumption and risk status among Australian university students vary by assessment questions. Drug Alcohol Rev 2009] 相似文献