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41.
用赖氏法重复测丙氨酸氨基转移酶(ALT)标准曲线10次,计算机作线性回归和曲线拟合。直线回归结果,酶活性在不高于97U的范围内,相关系数(R)=0.999,斜率(b)+2.55×10^-3,截距(a)=0.0286;而达到200U时,R=0.086,b=1.90×10^-3,a=0.066,,显著性检验两者之间差别为极显著。表明:97U以下线性较好但不过原点,大于97U之后开始明显偏离该线性。拟合 相似文献
42.
片剂含量均匀度计量检验新方案的研究 总被引:5,自引:0,他引:5
本文通过大量测试工作,查明10批国产小剂量片剂的含量分布,在此基础上提出了计量检验新方案。采用计算机模拟随机抽样的方法,通过计算绘制了USP XX,BP,JP和新方案在正态分布和10批实际分布下的OC曲线。结果表明,当用于测定生产规模的片剂批时,与国外片剂含量均匀度计数检验方案中统计特性最优的USP XX方案相比,新方案NEW能在化验工作量相近的前提下,作出更准确的判断;新方案SMA能在不降低判断准确性的前提下,减少化验工作虽约三分之一。新方案还可减免分析方法误差对判定结果的影响。 相似文献
43.
《临床检验仪器学》是一门实践性课程,为改变目前教学中实验场地局限、大型自动化检测仪器缺乏等限制,提出《临床检验仪器学》虚拟仿真教学探索思路。本文基于医学检验应用型人才培养目标,形成检验仪器学单个仪器和综合项目训练的虚拟仿真教学设计与管理举措;构建教学效果评价与质量监控的方法,显著提高学生的自主学习能力和综合实践能力;借助互联网共享优势促进医学检验实验教学的内涵建设。 相似文献
44.
目的 探讨目标教学结合Roy适应式情景教学在急诊科护理教学中的应用效果。方法 将分配到空军军医大学第一附属医院西京医院急诊科实习的护生110人作为研究对象,按进科先后顺序分为对照组和观察组,每组55人。对照组采用传统教学,观察组采用目标教学结合Roy适应式情景教学。评估两组实习护生情景模拟演练考核成绩和急诊急救能力。采用SPSS 22.0进行t检验和卡方检验。结果 观察组实习护生情景模拟演练考核教学目标,理论知识目标、技能目标、态度目标考核平均成绩分别为(9.09±1.21)分、(13.98±1.87)分、(9.32±0.95)分,对照组理论知识目标、技能目标、态度目标考核平均成绩分别为(8.41±1.17)分、(12.43±1.72)分、(8.72±0.83)分,观察组教学目标(理论知识目标、技能目标、态度目标)的掌握程度均优于对照组,差异有统计学意义(P<0.05)。观察组实习护生急诊急救能力优于对照组,差异有统计学意义(P<0.05)。结论 目标教学结合Roy适应式情景教学应用于急诊科护理教学,有助于提升实习护生的理论和实践技能,有助于培养实习护生的急诊急救能力。 相似文献
45.
目的 探讨基于以问题为基础的学习(problem-based learning,PBL)的情景模拟教学在重症医学科住院医师规范化培训中的作用和效果。方法 选取2019年3月至2019年12月在苏州大学附属第一医院重症医学科规范化培训的住院医师48人,分为试验组和对照组,每组各24人。试验组采用基于PBL的情景模拟教学,对照组采用传统教学。教学任务结束后比较两组规培学员成绩,对比和分析调查问卷结果差异。应用SPSS 17.0进行t 检验。结果 试验组的理论考核成绩(85.50±5.15)分和技能考核成绩(82.38±5.64)分均高于对照组[(77.04±8.69)分、(70.92±5.65)分],差异有统计学意义(P<0.05)。试验组在提升学习兴趣和效率、提高临床工作能力、强化临床思维能力、提高团队协作能力和提高医患沟通能力等5个方面均高于对照组,差异有统计学意义(P<0.05)。结论 基于PBL的情景模拟与传统教学相比优势明显,值得推广。 相似文献
46.
Kubicek每搏心输出量计算公式的三维有限元仿真研究 总被引:1,自引:0,他引:1
我们从 Kubicek模型三维有限元仿真的角度对 Kubicek每搏心输出量计算公式的临床应用价值进行了研究。在计算机仿真研究中 ,我们对比了模型仿真结果、具体采用 Kubicek每搏心输出量计算公式所得结果以及所设模型的理论计算结果。仿真结果表明 :模型中阻抗改变与主动脉中血液容积改变之间存在着近似的线性关系 ,证明了 Kubicek每搏心输出量计算公式具有一定的临床应用价值 ,同时也为心阻抗血流图基础理论提供了新的研究途径。 相似文献
47.
Technique are described whereby the clearance of the radiolabelled blood borne colloid can be continuously and reproducibly measured non-invasively from the same animal in vivo or from the isolated perfused intact liver in vitro. Using these techniques, the rate of removal of radiolabelled sulphur colloid by the mononuclear phagocytes in vivo and in vitro was shown to be biexponential. The pattern of clearance of colloid and the factors contributing to this were analysed with the aid of a computer program which mimicked the in vitro liver perfusion. 相似文献
48.
Given that knowledge regarding the etiology of comorbidity between disorders can have a significant impact on research regarding the classification, treatment, and etiology of the disorders, the ability to reject incorrect hypotheses regarding the causes of comorbidity is very important. A simulation study was conducted to assess the validity of the Neale and Kendler (1995) model-fitting approach in examining the etiology of comorbidity between two disorders. First, data were simulated under the assumptions of the 13 alternative comorbidity models described by Neale and Kendler. Second, model-fitting analyses testing the comorbidity models were conducted on the simulated datasets. Thirteen sets of data with varying model parameters were simulated to test Neale and Kendler's assertion that their model-fitting approach is appropriate across a range of potential prevalences and degrees of familiality. The validity of the model-fitting approach in examining unselected twin data and a combination of selected family data and unselected family data was explored. The model-fitting approach successfully discriminated several classes of comorbidity models, although discrimination between models within classes of related models was less accurate. Results suggest that the model-fitting approach can be a useful tool in examining the etiology of the comorbidity between disorders if the caveats of the present study's results are considered carefully. As predicted by Neale and Kendler, variations in the disorder prevalences and familial correlations did not affect the validity of their model-fitting approach, but affected the power to discriminate the correct model. As suggested by Neale and Kendler, the model-fitting approach can be applied to both unselected and selected data and to both twin and family data. 相似文献
49.
Karch R Neumann F Neumann M Szawlowski P Schreiner W 《Annals of biomedical engineering》2003,31(5):548-563
Topological and metric properties of Voronoi polyhedra (VP) generated by the distal end points of terminal segments in arterial tree models grown by the method of constrained constructive optimization (CCO) are analyzed with the aim to characterize the spatial distribution of their supply sites relative to randomly distributed points as a reference model. The distributions of the number N
f
of Voronoi cell faces, cell volume V, surface area S, area A of individual cell faces, and asphericity parameter of the CCO models are all significantly different from the ones of random points, whereas the distributions of V, S, and are also significantly different among CCO models optimized for minimum intravascular volume and minimum segment length (p < 0.0001). The distributions of N
f
, V, and S of the CCO models are reasonably well approximated by two-parameter gamma distributions. We study scaling of intravascular blood volume and arterial cross-sectional area with the volume of supplied tissue, the latter being represented by the VP of the respective terminal segments. We observe scaling exponents from 1.20 ± 0.007 to 1.08 ± 0.005 for intravascular blood volume and 0.77 ± 0.01 for arterial cross-sectional area. Setting terminal flows proportional to the associated VP volumes during tree construction yields a relative dispersion of terminal flows of 37% and a coefficient of skewness of 1.12. © 2003 Biomedical Engineering Society.
PAC2003: 8719Uv, 8710+e, 4720Ky, 0260Pn, 0230Oz 相似文献
50.
P. Heggelund 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1981,42(1):99-107
Summary The receptive field organization of complex cells was studied by analyzing interaction effects between two stationary flashing light stimuli. One was placed in the most responsive part of the receptive field to produce activity against which effects of the other in different visual field positions could be determined.The receptive field was spatially organized into antagonistic center and flanks just like the fields of simple cells. However, both center and flanks were found within the receptive field area where a single slit evoked discharge. Center and flanks were elongated along the optimal stimulus orientation. The flanks were displaced from the center normal to optimal stimulus orientation.In the center, ON- and OFF-responses were usually about equal in strength and the maximum ON- and OFF-responses occurred in about the same position. This shows that complex cells are activated by input from both ON- and OFF-center cells in the lateral geniculate nucleus (LGN) where the receptive field centers of the LGN cells overlap closely. This explains most of the specific features of complex cells, e.g., the spatially overlapping ON- and OFF-zones, the large response field, the repetitive firing when a slit moves over the receptive field, and the marked non-linear spatial summation.Strong flank suppression occurred with both ON and OFF. The effects were usually stronger on one side of the center. Maximal suppression occurred on the same side with both ON and OFF. This is consistent with the interpretation that complex cells are inhibited by input from both LGN ON- and OFF-center cells with overlapping receptive field centers.A model presuming that complex cells have overlapping but acentric excitatory and inhibitory fields was tested by computer simulation and shown to fit the experimental data. This is the same model as presented for simple cells in the preceding paper (Heggelund 1980), except that the excitatory and inhibitory fields of simple cells have input from either ON- or OFF-center LGN cells, whereas in complex cells they have input from both types.The project was financially supported by the Norwegian Research Council for Science and Humanities 相似文献