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51.
采用显微外科技术行阴囊纵膈皮瓣尿道下裂修复术18例,均获成功。其手术要点为:将阴茎腹侧纤维索条切除,充分伸展阴茎,皮瓣保留足够长度与宽度,克保血运;在显微镜下采用7-0尼龙丝线缝合,形成皮管,不缝皮肤,只缝皮下。硅胶管支架引流,加压包扎阴茎。本文对手术成功的原因进行了初步讨论。  相似文献   
52.
Objective: Permeability of basement membrane and all other barriers contains a term for membrane thickness (Δx). This naturally leads to development of methods for measuring Δx that are imprecise, inaccurate, expensive, subject to preparation artifact, and inattentive to variability. Although height and shape of permeability (P) vs. probe radius (α) curves are sensitive to Δx, ln(P) or ln(P/free diffusivity or Do) curves have shapes independent of Δx. It should, thus, be possible using such characteristics to determine fiber radius (rf) and void volume ratio (ε) without Δx. We developed such a method to derive membrane structure by the standard model of Ogston and present its experimental evaluation. Methods: Basement membranes were self-assembled using 1: 1 Matrigel: 0.01 M Tris/150 mM NaCl/1.0 mM CaCl2 buffer on 0.4-μ polycarbonate supports with transport measured in diffusion chambers using FITC-labeled hydroxyethyl starch probes from 25 to 102 Å in radius. Sampling was at 0.5 hr and then for each hour up to 5. Other membranes were measured 7 days after formation. Results: The best fit of the new technique occurred at 3 hr with R2 = 0.949 ± 0.003 SEM, rf = 36.8 ± 2.4 Å, and ε = 0.87 ± 0.02. Membranes studied for 7 days showed more variability but essentially the same characteristics. Conclusions: Membrane thickness is not necessary to reduce permeability of basement membrane to structure, and optimum sampling time is 3 hr.  相似文献   
53.
报告16例大肝癌手术切除治疗效果,癌块直径>7cm。其中巨块型12例,癌块>10cm9例;癌块>14cm3例,均经病理证实。Ⅱ期切除3例,均经肝固有动脉结扎加插管注药化疗,肿块缩小后再手术,术后生存1年4例,2年3例,3年4例,4年1例,全组中位生存期24.1个月,并对大肝癌的手术适应证及术式选择等进行了探讨。  相似文献   
54.
报告37例胆囊小隆起性病变,其中良性颈变34例,胆囊癌3例。结果:本组23例有临床症状,多表现为反复发作的右上腹疼痛或不适;病灶部位,大小,多少,有无合并胆石及病变性质与临床症状有关;B-us,OCG,CT的诊断符合率例如辚33/37,9/24和5/10(x^2=18.75,P<0.005)。认为对胆囊小隆起性病变的病灶≥10mm,有增大趋势,呈恶性图像,合并胆石或血清CEA升高的病例应及早手术治疗。  相似文献   
55.
The present trial was designed to evaluate clinical scores (single observer) of sodium lauryl sulphate (SLS)-induced skin irritation in a group of subjects (n = 10) over a 10-day period along with various skin function parameters. In order to avoid significant variations due to secondary phenomena, the following parameters were recorded with non-invasive instruments in this order: skin capacitance (C1; arbitrary units; CM420 Corneometer), transepidermal water loss (TEWL; g/m2.h; Evaporimeter) and laser Doppler flowmetry (CBFV: cutaneous blood flow values; Periflux). All examinations were performed during winter on reclined relaxed subjects present for at least 10 min in a test room with controlled temperature and relative humidity (t degrees: 19.5-20.7 degrees C and RH: 47.3-60.3%). The analysis of differential data (delta = value at tx-value before test; 2-way ANOVA) was made on single parameters as a function of site (volar forearm versus neck) and time (from 24 h after 48-h occlusion with 5% SLS up to 10 days later). The profile of erythema scores over time differed between neck and forearm, but the delta CBFV readings with the laser Doppler instrument did not detect significant site-time interactions. Roughness (blind evaluation with palpating finger) and capacitance readings (delta C1) showed significant differences between sites, but the profile over time was similar in both locations. delta TEWL did not differ according to anatomical location. The reason for different erythema scores on neck and forearm might be related to inherent regional variation of optical properties of the skin or to a substantial contribution of SLS-induced roughness to the readings of erythema.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
56.
报告接受彩色多普勒超声心动图检查的老年患者162例,其中75例有不同程度的主要动脉瓣关闭不全(Ar)。老年(Ar)的病因构成与中,老年前期者明显不同,主动脉,瓣钙化及原因不明者的比例占多数(67%)。主动脉瓣钙化者Ar程度多较重。主动脉瓣钙化及原因不明Ar患者的其他三个瓣膜返流检出率及和程度均明显高于无Ar的老年患者。表明多瓣膜退行性病变是此类Ar患者的原因之一。  相似文献   
57.
The aim of this study was to explore undergraduate and postgraduate dental students' understanding of a good learning experience by using 'reflection on learning' as described by Schon. Four groups of Year 4 BDS students and one group of postgraduate students in dental public health took part in a series of focus group discussions. The responses were grouped into four broad themes (a) active, practical and positive learning; (b) interactive/together learning; (c) personal learning; (d) theory into practice. Six educational models of good learning proposed by the students are described.  相似文献   
58.
以功效系数为目标函数,相应地确定了设计变量和约束函数,对塑料注塑机合模机构的参数进行优化计算,提高了机构的综合性能。  相似文献   
59.
Integrating human factors into the medical curriculum   总被引:3,自引:0,他引:3  
Background  The study of human factors is a scientific discipline that deals with the interactions between human beings and the elements of a system. This is important because shortcomings in these areas, if unchecked, can result in adverse outcomes. Research into human factors in industries where safety is paramount has provided the basis of countermeasures against human error. Adverse outcomes in medicine resulting from human error exact a high cost in both patient suffering and financial outlay.
CRM training  One of the approaches used to minimise the effect of human error is to train people in a set of knowledge, skills and attitudes that underpin the domain-specific competencies for that profession. These are referred to as non-technical skills (NTS). In aviation, such an approach has been shown to be both translatable from the training environment to the workplace and effective in reducing adverse outcomes.
Discussion  Medicine has incorporated this style of training, usually centred around simulator-based courses, but as yet in a piecemeal, episodic fashion which relies on participants volunteering to attend courses. Unlike other industries there is no systematic approach to linking the content of this teaching with the more conventional range of topics. As a consequence it is difficult to assess the impact of human factors training in medicine. This is partly because very little work has been done to date in identifying the key non-technical skills required in medicine, and the overall experience of workplace based assessment is limited. Lessons from other high reliability organisations may help to address the main challenges of developing the content, integrating it into the curriculum, reinforcing the concepts in the workplace through staff development and establishing its role in summative assessment.  相似文献   
60.
^60Co消毒与高温高压消毒胚胎骨的实验研究   总被引:1,自引:0,他引:1  
在12只健康家兔下颌骨体部的两侧各造成0.7cm×0.5cm×0.3cm的骨缺损区,分别置入^60Co消毒的胚胎骨和高温高压消毒的胚胎骨,发现高温高压消毒可以替代^60Co消毒胚胎骨进行移植,为临床提供了一种新的用作同种异体移植胚胎骨的消毒方法。  相似文献   
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