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101.
A prototype version of a recently developed transmission phantom for simulation of radionuclide bone studies was used in a Norwegian nationwide quality assurance project. The design of the phantom made it possible to perform a receiver operation characteristic (ROC) examination with respect to the detection of radionuclide accumulation in the ribs. The participants were also asked to report accumulation in the spinal column. Images obtained by means of a uniform source and a four-quadrant bar pattern were used to judge resolution and homogeneity with the collimator used in the bone studies. The overall performance of the laboratories was satisfactory, but considerable variations were found. There was a marked correlation between the physician's performance and the resolution and homogeneity of the camera. Reports from stationary imaging were generally better than those that were based on whole-body scans.  相似文献   
102.
This paper examines two approaches for the analysis of quantitative traits: (1) association studies and (2) linkage studies. The trait studied was Q1 from simulated Problem 2 data set in Genetic Analysis Workshop 9. Our purpose was to evaluate associations present in the data, to identify nongenetic and genetic predictors of the trait, and to explore the simulated genome for linkage. Through the association study, we found evidence for the primary major gene associated with this trait. The linkage study found evidence of residual genetic effect acting through other traits. Adjustments of Q1 for Q2 and Q3 led to a failure to find significant effects of MG2 and MG3. This supports the suggestion that adjustment for genetically influenced traits for effects of other genetic traits can reduce the power to detect major gene effects. In summary, we detected the major gene directly associated with the trait of interest through association studies. Linkage analysis detected evidence for two other genes associated to a lesser degree with the trait. © 1995 Wiley-Liss, Inc.  相似文献   
103.
Zusammenfassung Die Epilepsieforschung ist kein neues wissenschaftliches Feld—klinische und experimentelle Untersuchungen werden seit Jahrzehnten betrieben. Trotz dieser fortw?hrenden Bemühungen sind die Pathomechanismen der Epilepsie letztlich nicht vollst?ndig gekl?rt—allerdings gelangen in den letzten Jahren auch beachtliche Fortschritte. Vor allem durch die Kombination genetischer, molekularer und funktioneller Analysen konnten wichtige Teilaspekte der Entstehungsprozesse der Epilepsie aufgekl?rt werden. Der vorliegende übersichtsartikel soll nach einer kurzen Er?rterung der grunds?tzlichen Faktoren der Erregbarkeit einzelner Zellen und des neuronalen Zellverbandes in fünf kurzen Kapiteln einen überblick über den aktuellen Forschungsstand liefern. Innerhalb der ersten drei Abschnitte werden Ver?nderungen spannungsabh?ngiger Str?me, der synaptischen Transmission und deren Modulation sowie der Expression von Gap junctions beleuchtet. Darüber hinaus widmet sich ein Abschnitt morphologischen Ver?nderungen. Der letzte Teil behandelt Aspekte spezifischer genetischer Syndrome. Dieser Beitrag ist bereits in verkürzter Form in der Zeitschrift „Klinische Neurophysiologie“, Bd. 37 (2006), S. 1–9, unter dem Titel „Pathophysiologie der Epilepsie“ erschienen.  相似文献   
104.
从非演绎方法入手,从分析与综合、归纳与概括、类比与联想三个方面联系歌唱的思维过程,论述非演绎思维方法在歌唱过程中的运用。思维的非演绎方法贯穿于歌唱的全过程,它们之间存在着紧密的联系。掌握思维的非演绎方法对于歌唱水平的提高有积极的促进作用。  相似文献   
105.
458例尿路结石成分分析   总被引:4,自引:1,他引:3  
目的 探讨西安地区尿路结石的成分状况,为临床防治提供帮助。方法对458例尿路结石标本进行化学成分测定,并结合临床资料进行比较。结果尿路结石男性发病多于女性,男、女比为2.1:1,20一50岁为高发年龄,上尿路结石明显多于下尿路结石,上、下尿路结石之比为10.5:1。结石成分以混合结石占多数,为325例(71%),其中以草酸钙,磷酸钙与尿酸的混合结石为主。对比混合性结石及单纯性结石发现,各种成分所占比例基本一致。结论结石成分分析对于了解结石成因、预防结石形成和复发具有重要的意义。  相似文献   
106.
2005~2007年我国非甾体抗炎药市场应用分析   总被引:1,自引:0,他引:1  
目的:以骨骼肌肉系统使用非甾体抗炎药物为例,分析该类药物在2005~2007年的销售数量、销售金额及生产厂家风云榜。方法:采用药物分类累加的方法统计2005~2007年非甾体抗炎药的销售数量和金额排序,并对前10位药品销售数量和金额对比,及前10位厂家对比。结果:双氯芬酸稳居销售榜首,美洛昔康、布洛芬等药物位居其后。结论:新一代的非甾体抗炎药已经占据主要市场,各类药物各有特色,但是仍需注意其消化系统及心血管系统的不良反应。  相似文献   
107.
INTRODUCTION: The first-order kernel response of multifocal electroretinogram (mfERG) decreases in myopia. A recent study indicates that the flash ERG is also reduced with increased axial length. The aim of this study was to investigate the variations in the first-order response (K1) and the first slice of second-order response (K2.1) across the retina for different axial lengths. METHODS: Thirty healthy subjects with axial length from 23.72 to 28.13 mm (spherical equivalent refractive errors from plano to -10.50 D) were recruited for mfERG measurement using VERIS 4.0. All subjects were fully corrected after cycloplegic refraction and pupils were dilated prior to mfERG recording. There is one trough, n1, and one peak, p1, in the K1 response and three troughs, n1, n2, n3, and three peaks, p1, p2, p3, in the K2.1 response. The amplitudes and implicit times of K1 and K2.1 responses were analysed to determine the characteristic of the responses across retina and the correlation to axial length. RESULTS: The amplitudes of p1 (in the first-order kernel-K1) decreased in the central region and the paracentral region (ring 3) as the axial length increased. The central retinal region showed high rates of reduction in both n1 and p1 (in K1). The amplitudes of n1p1 and n2p2 (in the first slice of the second-order kernel-K2.1) were reduced in the paracentral region (from ring 2 to ring 5) as axial length increased. The average n1 and p1 in K1, and n1p1 and n2p2 in K2.1 mfERG responses are decreased in amplitude by 6-10% per millimetre elongation of axial length. CONCLUSION: Eyes with longer axial lengths, usually with high myopia, have a weaker mfERG response and this attenuation is across the measured retina (from central to paracentral regions) but different kernel responses show a different pattern of attenuation at different retinal eccentricities. The weaker mfERG responses may be related to the morphological changes associated with increased axial length.  相似文献   
108.
精子质量参数分析的标准化与质量控制的研究进展   总被引:4,自引:4,他引:0  
精液分析是评价男性生育能力的最基本测试。最近几年,对精液分析标准化的迫切需求已引起男科学家的广泛重视。本文对精子质量参数———精子密度、活动率和形态学分析的标准化及质量控制进行了综述。精子密度分析的关键是计数池的标准化,因此Cell-VU计数池应该是最佳的选择;精子活动率和精子形态学的分析由于主观性太强,CASA系统可能是其标准化的最终选择。精液质量参数分析的质量控制主要是质量控制材料的选择,以及在男科学实验室实施EQC和IQC项目,而一些监测质量控制的图表和计算方法应被相应地建立。  相似文献   
109.
BACKGROUND: Digital computer analysis of dermatoscopical images has been reported to facilitate the differential diagnosis of pigmented skin lesions in recent years. OBJECTIVE: The aim of our study was to perform digital computer analysis of a set of different melanocytic lesions and compare the objective results. METHODS: The set of 260 melanocytic lesions (150 excised difficult cases (46 melanomas, 47 atypical nevi, 57 common nevi and 110 unexcised common nevi) was automatically analysed by the digital dermatoscopical system microDERM. We searched for differences in asymmetry, size, compactness and colour distribution. Perimeter/area ratio was calculated. RESULTS: The perimeter/area ratio was detected as the most important criterion for differentiation between malignant and benign melanocytic lesions (sensitivity 91.3% and specificity 90.7% for malignant melanomas vs. all benign nevi; sensitivity 91.3% and specificity 80.8% for melanomas vs. clinically atypical nevi). Differences in size of the lesion, shape and asymmetry of colour were found and statistically verified. Using step-wise logistic regression the formula for calculation of probability of malignant nature of every analysed lesion was constructed. CONCLUSION: The perimeter/area ratio is a simple parameter for the differential diagnosis of melanocytic skin lesions.  相似文献   
110.
Analytical validation of a competitive direct SUNQuik ELISA with a reference High Performance Liquid Chromatography (HPLC) method and other methods including a minicolumn method and the VICAM Aflatest® system for aflatoxin in peanuts was conducted. Both the ELISA and the VICAM Aflatest® system, using the same peanut extracts were analytically comparable with the HPLC method (R=0.998, p<0.000). The minicolumn method was also found to be acceptable as a low cost rapid semi-quantitative test. Despite the large variation in sampling, the correlation between the SUNQuik ELISA and HPLC using the different peanut sub-samples was considered acceptable over the range of 0–1200 µg kg?1 (R=0.938). No false negatives were found using the SUNQuik ELISA and false positives were either nil or negligible in all the studies conducted. The repeatability of the SUNQuik ELISA run on the same day was good with only±10% deviation. The reproducibility of the SUNQuik ELISA between days was also acceptable, but with a higher deviation. Applying the SUNQuik ELISA for aflatoxin surveys of peanuts in Indonesia proved that the method can deliver high quality, cost- and time-effective analysis with very little establishment capital and maintenance.  相似文献   
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