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1.
根据公认的眼科解剖学数据,提出后房型人工晶体植入屈光度的术前预测方法:IOL(D)=1.02(+21D+2X)。经人工晶体专用眼科A超36眼实测对比,无显著差异,认为在地市级医院和县级医院后房型人工晶体植入术推广中具有积极意义。  相似文献   
2.
When the distance between linked loci is expressed in terms of the correlation between the identity-by-descent (idb) values of the loci, then a path model may be used to order loci with data on sib-pairs and their parents. The relationship between the recombination fraction and the correlation coefficient is developed and a method for fitting a covariance matrix predicted by a specific ordering of loci to an observed covariance matrix is proposed. © 1993 Wiley-Liss. Inc.  相似文献   
3.
An improved sib-pair test for linkage is introduced which is superior to the previously proposed tests. The test is derived from the standard chi-squared goodness of fit statistic by restricting the alternative hypothesis to the genetically possible. Critical values are given and exact power comparisons are made with the previously proposed tests. The new test is shown to be more powerful for finite samples as well as being asymptotically uniformly most powerful. © 1993 Wiley-Liss, Inc.  相似文献   
4.
The duration of the late exteroceptive suppression period (ES2) of temporal muscle EMG activity has been reported to be reduced in patients suffering from chronic tension-type headache. Methods of recording and analysing ES2 have varied between centers and reproducibility of results within subjects , although insufficiently studied, has generally been poor. ES2 was investigated in 30 healthy subjects, using a computerized technique of recording, rectifying and averaging the EMG signals. Hour to hour and week to week variations of ES2 durations were calculated, and the influence of pain during a cold pressor test and of sustained muscle contraction on ES2 durations was investigated. The intra-individual variation of ES2 durations was 16.0% from hour to hour and 20.7% from week to week. The inter-individual variation was 36.7%. The present method for analysis of ES2 periods proved to be reliable, as the intra-observer variation was 4.2% and the inter-observer variation 4.6%. ES2 periods were significantly shorter on the first compared to the second day of examination ( p = 0.006) and during experimental pain ( p = 0.0005). We recommend the use of the computerized averaging technique in future studies and caution against the dependence of results upon factors such as conditioning and pain.  相似文献   
5.
The ubiquitous existence of calcium-activated neutral protease (CANP, calpain), an enzyme whose activity is regulated by calcium ions and a specific endogenous CANP inhibitor (calpastatin), is well known. Although there has been much investigation concerning the distribution and role of CANP, investigations of the distribution of the CANP inhibitor using immunohistochemical techniques are rare. We made antiserum against a 40K fragment of cDNA corresponding to two C-terminal repeats of rat liver CANP inhibitor expressed in Escherichia coli. Using this antiserum, we examined the distribution of CANP inhibitor in the rat central nervous system by the ABC technique and compared it with the distribution of CANP. Neurons and glias were stained, with the cytosol stained diffusely and the cell membranes stained clearly and strongly. Axons and myelin were stained faintly, but nuclei and vessels were not stained. The distribution of CANP inhibitor was thus found to be similar to that of CANP.  相似文献   
6.
本文介绍了一种应用微机BASIC语言的屈光学矩阵算法程序,可方便、迅速地解决许多眼科屈光学计算问题,如共轴球面折射系统、共轴球面反射、折射系统、球、柱镜偏心棱镜效应计算和散光柱镜系统的斜交球、柱镜组合计算等等。  相似文献   
7.
对60例胃癌进行了粘液组织化学和癌胚抗原免疫组织化学研究。结果表明:胃癌发病率肠型和胃肠混合型占多数。60例胃癌中含大肠型粘液者占50例,而单纯含胃型粘液为极少数。癌胚抗原分布方式,肠型胃癌与胃肠混合型胃癌比较无显著差异性(P>0.05)。癌胚抗原的阳性率,胃肠混合型胃癌高于肠型胃癌,两者之间有非常显著差别(P<0.01)。认为选用能显示硫粘蛋白和氧乙酰基唾液酸粘蛋白的粘液组织化学方法,作为胃癌组织分型和确定胃粘膜肠化性质,对癌前病变诊断有一定价值。  相似文献   
8.
Standard imaging techniques using a curved linear array echoendocope are summarized to facilitate the attainment of expertise in endoscopic ultrasonography and endoscopic ultrasound‐guided fine needle aspiration, and to promote the widespread use of this diagnostic and therapeutic tool. Typical images of the mediastinal organs, the bilio‐pancreatic systems and neighboring organs by scanning from the esophagus, stomach, duodenal bulb, and descending portion of the duodenum, are shown in a sequential manner. The basic techniques of endoscopic ultrasound‐guided fine needle aspiration are also presented.  相似文献   
9.
The aim of this prospective study was to characterize an implant patient population exhibiting clinical signs of peri‐implantitis and to determine subsequently the incidence of progressive attachment loss. The predictive values of diagnostic parameters were evaluated. 25 patients with 54 endosseous implants that had been loaded for 41±15 months were included in the study. Clinical parameters included the assessment of plaque, bleeding on probing, probing depth, attachment levels, and Periotest® values. Probing measurements were performed in duplicate by means of a controlled force electronic probe (Periprobem). Peri‐implant crevicular fluid samples were collected and assayed for neutral proteolytic enzyme (NPE) activity (Periocheck®). Analysis of duplicate baseline probing data revealed a high degree of reproducibility (mean difference: 0.1±0.3mm). A minimum threshold of 1.0mm (>3×S.D.) loss of probing attachment was chosen to classify a site as positive for breakdown. Alternatively, the tolerance method was employed to identify sites with progressive attachment loss. After 6 months, irrespective of the analytical method, 6 percent of all sites (in 19% of the implants) and 28% of the patients had experienced further per attachment loss. There were significant differences ( p <0.05) in mean plaque (73% vs. 45%) and NPE (36% vs. 12%) scores between patients with progressive peri‐implantitis and those with stable peri‐implant conditions. Both bleeding on probing and the NPE‐test were characterized by high negative predictive values, and thus negative scores can serve as indicators for stable peri‐implant conditions. For monitoring peri‐implant health during recall visits, attachment level recordings with a controlled force electronic probe in conjunction with enzymatic diagnostic tests of the host response can be recommended.  相似文献   
10.
尼氏小体染色方法的改进及其在神经病理学研究中的应用   总被引:6,自引:0,他引:6  
组织或细胞的染色在病理学诊断、科学研究和教学工作中,都具有非常重要的意义和使用价值。组织切片染色的质量好坏对于医学诊断,科研和教学至关重要。为了更好的研究神经组织,使医学诊断、科研和教学工作更为方便,本文对Toluidine Blue(甲苯胺蓝)染色方法做了一些改进。在传统的甲苯胺蓝染色过程中,仅考虑对细胞核和尼氏小体进行染色,未考虑细胞浆和其他细胞器:而改进后的甲苯胺蓝染色方法在甲苯股蓝染色后用伊红再染色,既考虑对细胞核和尼氏小体进行染色,也对细胞浆进行了染色。结果显示传统的Toluidine Blue染色结果光镜下观察,细胞核和尼氏小体都可见,即尼氏小体为深蓝色,细胞核为蓝色,染色背景为淡蓝色;改进后的染色结果光镜下观察,尼氏小体为紫蓝色,细胞核为蓝色,染色背景为粉红色。可见,改进后的染色方法染出的组织切片比传统的要清晰、美观。随着科学技术的飞速发展,病理学的研究也随之发展,病理技术势必进一步提高,来适应科技的进步和医学的发展。改进的尼氏小体染色法能够使脑组织切片更清楚观察,更有利于医学工作者对神经组织及尼氏小体的研究。  相似文献   
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