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951.
目的 确定MRI和CT评估退行性颈椎滑脱关节突关节矢状位不对称角的可靠性。方法 利用4度评估法,3个评估者对60位病人的76个关节突关节矢状位角的不对称程度在轴向位MRI和CT上进行单盲和随机测评,结果用Kappa系数进行统计分析。 结果 当评估颈椎关节突关节矢状位角的不对称性时,CT和MRI的一致性为0.76(加权K值,P<0.001),一致率为82% (62 vs 76),可认为方法间有比较好的一致性,三个测评者在MRI和CT中的k值范围分别为0.61~0.74和0.65~0.81,可认为测评者间用MRI测评时的信度为比较可靠,用CT测评时为比较可靠到非常可靠,但测评者内的信度无论是MRI还是CT都比测评者间的信度要高。 结论 MRI和CT在评估关节突关节矢状位角的不对称性时无论是方法间的一致性,还是组间或组内的信度,都有较好的一致性,这表明MRI用于测评关节突关节矢状位角度的不对称性是比较可靠的。因此,用MRI测评时没有必要再增加额外的CT扫描。  相似文献   
952.
Moon KC  Park SY  Kim HW  Hong HK  Lee HS 《Histopathology》2002,41(2):158-165
AIMS: In glomerulonephritis, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) may play important roles in the formation of crescents. These studies are designed to evaluate the expression patterns of ICAM-1 and VCAM-1 in human crescentic glomerulonephritis and to determine the cellular origin of adhesion molecules in the crescentic lesions. METHODS AND RESULTS: We examined the expression of ICAM-1 and VCAM-1 proteins in renal biopsies with cellular (n=7), fibrocellular (n=9) or fibrous (n=4) crescentic glomerulonephritis, and six controls by immunohistochemistry. mRNA expression of ICAM-1 and VCAM-1 was further evaluated by RNA in-situ hybridization. Cytokeratin or CD68 immunohistochemistry was performed on the same sections, where in-situ hybridization had been carried out. In cellular crescents, ICAM-1 and VCAM-1 proteins were over-expressed to a similar extent. Of the three types of crescents, the extent of ICAM-1 immunopositivity was the greatest in the cellular crescents and decreased towards the fibrous crescents (P < 0.05). Yet the extent of VCAM-1 immunoreactivity was not different between the types. Fibrous crescents still contained some epithelial cells and showed only VCAM-1 expression. In the glomeruli with cellular or fibrocellular crescents, the extent of ICAM-1 immunopositivity in the glomerular tufts was significantly larger than that of VCAM-1 (P < 0.05). In an in-situ hybridization study, the mRNA expression patterns of ICAM-1 and VCAM-1 paralleled their protein expressions. A double-labelling study showed that the signal for ICAM-1 and VCAM-1 mRNAs was mainly present in cytokeratin-positive and CD68-negative cells in the crescentic lesions. CONCLUSIONS: These results suggest that glomerular parietal epithelial cells in cellular crescents up-regulate both ICAM-1 and VCAM-1, and that some epithelial cells retained in fibrous crescents persistently over-express VCAM-1, but not ICAM-1. They also suggest that ICAM-1 is involved in early leucocyte recruitment into glomeruli in crescentic glomerulonephritis.  相似文献   
953.
This study examined the effects of vitamin E on the prevention of aspirin-induced gastric lesions. The study was divided into two phases. Phase 1 determined the effects of various doses of palm vitamin E on the factors affecting mucosal integrity. Thirty-two male rats of the Sprague-Dawley strain (200-250 g) were randomly divided into four groups. Group I was fed a normal diet (control), Groups II, III and IV were fed a diet supplemented with palm vitamin E in a dose of 60 mg/kg food, 100 mg/kg food and 150 mg/kg food, respectively. The rats were killed after 4 weeks of feeding for the determination of gastric malondialdehyde (MDA), acid and mucus content. There was a significant decrease in gastric MDA and gastric acid in all the palm vitamin E supplemented groups compared to control. However, these doses of palm vitamin E had no significant effect on gastric mucus. The phase 2 study determined the effect of multiple doses of palm vitamin E and tocopherol on the prevention of aspirin-induced gastric lesions. Fifty rats of the same weight and strain were randomized into seven groups. Group I was fed a normal diet; groups II to IV were fed with a palm vitamin E enriched diet in doses of 60 mg, 100 mg and 150 mg/kg food, respectively; groups V to VII were fed with a tocopherol-enriched diet in doses of 20 mg, 30 mg and 50 mg/kg food, respectively. After 4 weeks of feeding with the respective diets the rats were challenged with a single intra-gastric dose of 400 mg/kg body weight aspirin suspended in propylene glycol. The rats were killed 6 h post-aspirin exposure for the determination of gastric lesion index and gastric parameters as mentioned in the phase I study. The gastric lesions index was significantly lower in all the vitamin E groups compared to control. The lowest ulcer index was observed in the groups that received 100 mg of palm vitamin E and 30 mg tocopherol in the diet. However, there was no significant difference in ulcer indices between palm vitamin E and tocopherol-treated groups. The lower ulcer index was only accompanied by lower gastric MDA content. We conclude that both palm vitamin E in doses of 60 mg, 100 mg and 150 mg/kg food as well as tocopherol in doses of 20 mg, 30 mg and 50 mg/kg food are equally effective in preventing aspirin-induced gastric lesions. The most probable mechanism is through their ability in limiting the lipid peroxidation that is involved in aspirin-induced gastric lesions.  相似文献   
954.
Usage of liquid-based cytology has resulted in better cellular preservation with enhancement of nuclear features. The purpose of this retrospective 2-yr study (January 1999 through December 2000) was to evaluate the cellular features of endocervical gland involvement by a high-grade squamous intraepithelial lesion (HSIL) vs. endocervical adenocarcinoma in situ (AIS) on cell samples processed by the ThinPrep method as compared to conventional smears. Of the 97 cases of CIN III diagnosed on cytology, 52 (54%) showed surface endocervical gland involvement by CIN III and form the basis of this study. There were also six cases of endocervical AIS diagnosed on histology with prior cytology. The architectural features of HSIL involving endocervical glands and AIS were similar to those previously reported on conventional smears. A consistent finding of HSIL involving endocervical glands was the loss of central cell polarity and piling within cell groups, a finding not present in AIS. Central cell polarity was maintained in cellular groupings of AIS. In addition to the cellular feature present on conventional smears, micronucleoli were clearly visualized in cells of HSIL involving endocervical glands and prominent nucleoli were present in AIS. Apoptosis and mitoses were clearly visualized in both entities. Endocervical gland involvement by HSIL has characteristic cell patterns and features on liquid-based/thin-layer cytology that permit their distinction from AIS.  相似文献   
955.
Histologically, the marginal zone pattern of the lymph node is characterized by lymphoid follicles with three distinct layers. The inner layer is composed of follicular center zones, the middle layer of darkly stained mantle zones, and the outer layer of marginal zones. However, the marginal zone pattern is rarely seen in reactive lymph nodes except for mesenteric lymph nodes. We describe the clinicopathologic, immunohistochemical and genotypic findings of six cases of reactive follicular hyperplasia exhibiting the marginal zone pattern. The patients comprised three males and three females (age range 24 to 63 years; medium 56 years). Follow-up data were obtained from five patients. None of them developed malignant lymphomas during the follow-up period of from 5 to 204 months (median 68 months). Histologically, the lesion was characterized by numerous lymphoid follicles and partial distortion of lymph node structure. Varying degrees of progressive transformation of the germinal center (PTGC) were noted in the four cases. The marginal zone pattern was observed in some or most of the lymphoid follicles including PTGC. The marginal zone B cells were small to medium-sized lymphocytes with round or slightly indented nuclei and a broad rim of pale cytoplasm. Some of them had a monocytoid appearance. They were CD20+, CD79a+, sIgM+/-, sIgD-, CD5-, CD10-, CD21-, CD23-, CD43-, CD45RO-, Bcl-6-, cyclin D1-, EMA- and p53-. A portion of them were Bcl-2 positive. Occasional large lymphoid cells with round or indented nuclei and moderate amounts of cytoplasm were observed in the marginal zone in four cases. These large lymphoid cells were usually CD20 positive, but Bcl-6 negative. A small number of them contained polytypic intracytoplasmic immunoglobulins. The polytypic nature of B lymphocytes was demonstrated by immunohistochemistry and polymerase chain reaction. Recognition of unusual marginal zone hyperplasia in reactive lymph node lesions is important to avoid confusion with nodal involvement in various low-grade B cell lymphomas presenting a marginal zone distribution pattern.  相似文献   
956.
颈椎脊神经沟及其沟内段脊神经形态学观察   总被引:3,自引:1,他引:3  
目的 探讨脊神经沟与沟内段脊神经受嵌压的关系。方法 取 6 0具成尸 (男 2 8,女 32 ) 12 0侧颈椎 ,对脊神经沟外口宽度、深度及其沟内段脊神经前支横径进行观察 ,并统计脊神经前支横径与脊神经沟外口宽度之比。结果 ①脊神经沟外口宽度、深度自颈 3至颈 6均逐渐增大 ,其平均值分别为 4 5± 1 2mm和4 3± 1 2mm ;② 3到 7颈神经前支横径逐渐增大 ,平均值为 2 9± 1 0mm ;③颈神经前支横径与脊神经沟外口宽度之比 ,颈 5最小 (1∶1 5 4 ) ,颈 4次之 (1∶1 6 7) ,颈 3最大 (1∶1 75 )。结论 脊神经沟与沟内段脊神经受累关系密切 ,下颈段 (5、6 )颈神经受累机率可能大于上颈段 (3、4 )。  相似文献   
957.
颈深筋膜及筋膜间隙的计算机三维重建   总被引:1,自引:0,他引:1  
目的 :对颈深筋膜及深筋膜间隙进行计算机三维重建以显示其立体结构。方法 :用生物塑化技术制作薄层断面标本 ,在SGI工作站上 ,采用双线提取筋膜及间隙轮廓的方法对颈深筋膜及其间隙进行了三维重建。结果 :重建出咽后间隙、颈动脉间隙和内脏间隙及颈部的大血管和重要器官。重建结构均能单独显示、任意搭配显示或总体显示 ,可在三维空间位置上绕任意轴旋转任意角度。结构 :用双线法提取筋膜及间隙轮廓 ,能重建出筋膜间隙并能同时清楚显示间隙内的结构 ,为筋膜间隙的计算机三维重建提供了一种新的方法  相似文献   
958.
目的 明确颈深筋膜的分层及筋膜间隙的位置、毗邻 ,为颈深筋膜间隙的影像识别与分析提供参考 ,为临床诊治感染蔓延、肿瘤侵润提供解剖学依据。 方法 采用低温冰冻和生物塑化技术用 17例标本 ,制作了颈部连续薄层横断面 ,对颈深筋膜及筋膜间隙进行了观测。从颈部薄层塑化断面标本上 ,用双线提取间隙轮廓的方法 ,在SGI工作站上对颈深筋膜间隙进行三维重建。 结果  1.颈深筋膜应分为四层 ,颈深筋膜深层分为翼筋膜和椎前筋膜 ,颈深筋膜各层均参与颈动脉鞘的形成。 2 .颈动脉间隙是一开放的间隙 ,其后外侧与颈后间隙相通 ;证实了危险间隙的存在。 3.重建出咽后间隙、颈动脉间隙和内脏间隙的三维图像 ,并能同时显示间隙内的主要结构。结论 得出了颈深筋膜和筋膜间隙的模式图 ,并为筋膜间隙的三维重建提供了一种新的方法。  相似文献   
959.
目的:探讨Wnt-1、β-catenin蛋白在子宫颈鳞状细胞癌( cervical squamous cell carcinoma, CSCC)中的表达及其与侵袭转移的关系。方法采用免疫组化EliVision法检测78例CSCC组织和30例正常子宫颈组织中Wnt-1、β-catenin蛋白表达。结果在正常子宫颈组织中,Wnt-1、β-catenin蛋白的阳性率分别为20.0%和10.0%;CSCC组织中,Wnt-1、β-catenin蛋白的阳性率分别为56.4%和74.4%,二组差异有统计学意义(P<0.001)。33例CSCC淋巴结转移中Wnt-1、β-catenin蛋白的阳性率分别为72.7%和90.9%;45例CSCC无淋巴结转移中Wnt-1、β-catenin蛋白的阳性率分别为44.4%和62.2%。 Wnt-1、β-catenin蛋白表达与CSCC的分化程度( P <0.05)、浸润深度及 FIGO 分期均有关( P <0.05),与患者年龄、肿瘤大小等均无关。Spearman相关性分析显示:Wnt-1与β-catenin蛋白表达呈正相关关系(rs =0.490,P<0.001)。结论 Wnt-1、β-catenin蛋白的表达异常可能参与CSCC的发生、发展及转移,Wnt-1、β-catenin蛋白均可作为预测CSCC侵袭、转移的潜能及临床预后的指标。  相似文献   
960.
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