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31.
根据七年制医学生培养要求,在“生物物理技术”教学中,除介绍有关物理方法与技术的原理及在生物医学中的应用外,还尝试了小论文写作和渗透科研思路、方法培养的探索。  相似文献   
32.
5992例孕产妇梅毒筛查与分析   总被引:1,自引:0,他引:1  
目的 了解妊娠期梅毒的流行情况及对围产结局的影响。方法 对5992例孕产妇进行甲苯胺红不加热血清试验(TRUST)筛查,对TRUST阳性病例再进行梅毒螺旋体血清颗粒凝集试验(TPPA)确诊。并对围产结局进行观察分析。结果 5992例孕产妇,检出梅毒患者43例(0.72%),其中30例经青霉素治疗的患者其新产儿经半年以上随访无1例感染梅毒,在未治疗的13例患者中有10例分娩的新生儿TPPA滴度均≥1:40,其中2例为先天性梅毒。1例为死亡梅毒婴儿。结论 开展妊娠期梅毒血清学的产前筛查,加强对妊娠期梅毒的治疗,对减少先天性梅毒的发生尤为重要。  相似文献   
33.
Although both diabetes and the efficacy of medical management are international issues, psycho-educational interventions might be culturally bound. Blood Glucose Awareness Training (BGAT) is a psycho-educational program for patients with type 1 diabetes mellitus. It is focused on improving recognition and management of extreme blood glucose levels, and is the best documented American psycho-educational program for this purpose. A randomized controlled clinical trial of BGAT's long-term benefits in a non-American setting has been lacking. One hundred and eleven adults with type 1 diabetes mellitus from Switzerland and Germany participated. After a 6 months baseline assessment, subjects were randomly assigned to receive either 2 months of BGAT (n = 56) or a physician-guided self-help control intervention (n = 55). BGAT improved recognition of low (p = 0.008), high (p = .03), and overall blood glucose (p = 0.001), and reduced frequency of severe hypoglycemia (p = 0.04), without compromising metabolic control. BGAT reduced both the external locus of control (p < 0.02) and fear of hypoglycemia (p < 0.02). BGAT was efficacious in reducing adverse clinical events and achieving clinically desirable goals in a European, as well as American setting.  相似文献   
34.
Summary This study was undertaken in order to determine the time course of the process by which information derived from a visual target is used to accurately set the amplitude of a simple motor response. We refer to this process as response specification. Separate auditory and visual cues were given to the subjects in order to independently control the moment of response initiation and the time available for processing amplitude information from the target. Six subjects initiated impulses of isometric force in synchrony with the last of predictable series of regular tones. Response amplitudes were to match one of three visual target steps occurring at random times between 0 and 400 ms before the response-synchronizing tone. Using these separate auditory and visual cues, we were able to systematically vary the time interval between target presentation and response onset, termed here Stimulus-Response or S-R interval. Target steps were presented in blocks of either predictable (simple condition) or unpredictable (choice condition) amplitudes. The peak forces and the peaks of their time derivatives were analyzed to determine how subjects achieved accuracy under the different conditions and at different S-R intervals. The trajectories of responses produced in the simple condition were independent of the S-R interval. In contrast, when targets were presented in unpredictable order, the distribution of the peak forces of the subjects' responses depended on the S-R interval. At short S-R intervals (<125 ms), subjects made responses whose peak forces were distributed around the center of the range of target steps. These responses formed a unimodal, but broad distribution which was independent of actual target amplitude. With increasing S-R interval (>125 ms), the distributions of peak forces gradually shifted toward the correct target amplitudes, with the means reaching the appropriate amplitudes at S-R intervals of 250–400 ms. At S-R intervals comparable to a reaction time, the range of peak forces was constricted to a similar extent as previously observed in a reaction time task (Hening et al. 1988). We found that the gradual improvement of accuracy was not achieved through changes in trajectory control: at all S-R intervals, subjects utilized a pulse-height control policy (Gordon and Ghez 1987a). Different peak forces were achieved by varying the rate of rise of force, while force rise time was held relatively invariant. We did find, however, that within the constraints imposed by rise time regulation, compensatory adjustments to the force trajectories (Gordon and Ghez 1987b) were greatest during the period of specification. We conclude that (1) subjects can initiate their responses independent of the degree of specification achieved and that the normal process of specification of amplitude begins earlier and continues longer than the latency of responses in a reaction time task; (2) before target presentation, subjects prepare a default response whose amplitude is biased by prior experience with the targets presented in the task. We hypothesize that the central mechanisms that specify response amplitude do so by a progressive adjustment of the default parameters.  相似文献   
35.
目的了解我市HIV、HCV、HBsAg、梅毒在一般献血人群的感染情况,确保输血安全。方法采用酶联免疫吸附试验检测抗-HIV、抗-HCV、HBsAg、RPR和TRUST试验检测梅毒。结果在献血人群中HBsAg阳性率为5.36%;抗-HCV阳性率为1.35%;梅毒阳性率为0.42%。结论多次献血者HBsAg检测阳性率较低;有献血浆史的献血者抗-HCV检测阳性显著高于一般人群。  相似文献   
36.
The reliability of the Japanese public telephone facilities to transmit electrocardiograms (e.c.g.) for computer interpretation was assessed. The International Business Machine's (IBM) e.c.g. computer program by Bonner was used. No appreciable distortion of e.c.g. was observed following repeated transmission from hospitals separated by 1000 km. Thirty-four normal and 66 abnormal e.c.g.s. were transmitted twice. Identical results were observed in 97% of normals and 92% of abnormals. Following these fundamental experiments, 1236 patients' e.c.g.s. were transmitted for computer intepretation. The study showed that 98·6% (1219 cases) were technically satisfactory and 1·4% (17 cases) were not. The 17 unsatisfactory cases were classified into ten unreceivable data formats, six inconsistent measurements and one unacceptable noise level. The authors concluded that the Japanese public telephone facilities were acceptable for the transmission of e.c.g.s. for computer interpretation.  相似文献   
37.
A PC-AT based program for conversion of magnetic resonance imaging (MRI) scans into coordinate input for finite element mesh generation is presented. The program is written in Borland C + +3.1 and is compatible with every general-use personal computer, permitting the use of MS-DOS 3.0 or higher with a Microsoft mouse. The program is menu driven and does not demand specialised knowledge from the user. The system and memory requirements are minimal -- 640 kB RAM -- and it runs as a stand-alone program. A second program allows the construction of a three-dimensional representation of the limb sub-structure and generation of the FE mesh from the converted cross-sectional scans. The capabilities of the program are demonstrated using cross-sectional scans of the upper arm; the fat, muscle and bone contours were obtained to a very high level of precision (0.4 mm).  相似文献   
38.
Molecular analysis of circular excision products and composite genomic switch regions has demonstrated that in mice, immunoglobulin (Ig) isotype switching from IgM to IgE often proceeds sequentially via IgG1. Based on analysis of Ig production in cell cultures, it has been suggested that human B cells may switch to IgE via IgG4, whereas limited molecular data from in vitro switched B cells suggest a direct IgM to IgE switch program. To obtain a quantitative assessment of direct versus sequential IgE switching in humans, we have analyzed the nucleotide sequences of 29 composite Sμ/S? switch regions from freshly isolated human B lymphocytes from patients with atopic dermatitis and from B lymphocytes induced to switch to IgE synthesis in vitro. The data show that in these B cells IgE isotype switching progressed directly from IgM to IgE. We conclude that, in contrast to the murine IgM/IgE switch program, the IgM to IgE switch in B lymphocytes from patients with atopic dermatitis as well as in vitro stimulated B cells from healthy donors preferentially proceeds via direct Sμ to S? switch recombination.  相似文献   
39.
We review the methods in the ranking of clinical psychology doctoral programs provided by Stewart, Roberts, and Roy (2007). Using our own program as an example, we identify several areas of concern (e.g., authorship credits, criteria applied, faculty attrition). The inaccuracies identified for our program ranking, in combination with methodological concerns highlighted by previous commentaries, suggest that the validity of the rankings can be called into question.  相似文献   
40.
The aims of the present study were as follows:
  • 1). to evaluate the medical outcomes of two treatment and educational asthma programs
  • 2). to determine by cost-analysis both cost and economic outcome of the programs
  • 3). to perform a cost-benefit analysis (determining the net cost-benefit) and a cost-effectiveness analysis (determining the cost per unit of effect and the incremental cost-effectiveness ratio) from the perspective of health program policy makers (HPP; indirect costs, i.e., loss of productivity, excluded) and of society as a whole (Saw; all costs included).
Patients were randomly assigned to a complete (CP; n = 32) or reduced (RP; n = 33) program: the RP group received a reduced education (self-reading of an educational booklet on asthma), while the CP group attended an “asthma school”, consisting of six lessons based on the same booklet and including educational videotapes. Both programs included peak-flow monitoring and treatment according to international guidelines, and follow-up. The outcome variables (asthma attacks, urgent medical examinations, admission days, working days lost) did not differ significantly between CP and RP. Morbidity savings were $1894.70 (CP) and $1697.80 (RP) according to Saw, and $1349.50 and $1301.80, respectively, according to HPP. The net cost-benefit was $1181.50 for CP and $1028.00 for RP, and the cost-benefit ratio per dollar spent was 1:2.6 for CP and 1:2.5 for RP, according to Saw. One day of admission prevented had a cost of $110.20 (CP) and $94.10 (RP). CP gave slightly better results and was slightly more cost-effective than RP in improving patients' welfare. It cannot be excluded that the retrospective analysis used to determine baseline costs might have inflated differences for both groups. Sensitivity analysis was slightly in favor of RP when the outcome variables were tested at their upper and lower 95% CI.  相似文献   
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