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31.
Kim  SH; Chang  KH; Song  IC; Han  MH; Kim  HC; Kang  HS; Han  MC 《Radiology》1997,204(1):239
  相似文献   
32.
脾脏钝伤的CT诊断   总被引:2,自引:1,他引:1  
本文回顾性分析了32例脾脏钝伤CT平扫的表现;对脾损伤进行CT分类;指出腹腔积血和脾周血块(“哨兵血块征”)在诊断脾损伤方面的作用。CT平扫诊断钝性脾脏损伤是一种敏感、可靠的方法,可帮助外科医生制订治疗方案。CT平扫诊断钝性脾损伤的灵敏度为94%,诊断正确率为91%  相似文献   
33.
One of the pyrimidine compounds, 2-piperadino-6-methyl-5-oxo-5,6-dihydro(7H)pyrrolo[3,4-d]pyrimidine (MS-818), has neurotropic effects in vitro. Therefore, we studied the effect of MS-818 on the regeneration of the peroneal nerve in C57BL/6J mice after a crush injury. Two test groups, which received a daily intraperitoneal injection of 5 mg/kg or 10 mg/kg MS-818, respectively, were compared with controls, which received daily intraperitoneal injections of physiological saline, over a 14-day period. The maximum foot-width ratio (crushed side/uncrushed side) was obtained on days 1, 8 and 14 after the crush injury, and the various morphometric parameters were evaluated at both 5 and 10 mm distal to the proximal portion of the crush site. The significant effects of MS-818 included a larger maximum foot width (P<0.04) and a greater number of unmyelinated axons per nerve at both levels (P<0.003) in both test groups than in controls. MS-818 had no significant effects on body weight, the increase of total transverse fascicular area after the crush injury, the total number of myelinated fibers with their size distributions, or the number of nuclei of Schwann cells and macrophages. Therefore, we conclude that MS-818 promotes axonal sprouting and elongation after a crush injury in mice.  相似文献   
34.
Using hierarchical cluster analysis, applied to 47 cases of Guillain-Barre Syndrome (GBS) incident in South-West Stockholm (SWS) during the period from January 1973 to June 1992, we identified three major clinicoepidemiological subgroups. The first subgroup, 25.5% of the cases (26.7 ± 6.7 years), recorded a peak incidence at ages 20–29 years and presented significant differences from other subgroups, a high proportion of cases with onset at low age preceded by respiratory infection (83.3%) and with normal motor conduction velocity (50.0%). Also found, were less affected biological parameters, a rapidly progressive course and independence in gait at one month after onset. A second subgroup, 27.7% of cases, was severely affected, clinically and functionally. It consisted predominantly of young individuals (22.7 ± 11.1 years), with a high incidence (69.2% of cases) in autumn. A third subgroup, comprising 40.47; of cases, was older (61.1 ± 11.0 years) and, in general, also severely affected. The incidence of this form appeared to be invariant with time.  相似文献   
35.
OBJECTIVE: To understand the role of nasal mucous epithelial cells to hypoxia in early stage of nasal polyps(NP) formation. METHODS: Epithelial cells of NP and inferior turbinate (IT) were cultured without serum under normal oxygen and hypoxia, and stimulus of inflammatory cytokines. Erythropoietin (EPO) was regarded as hypoxia mark, and expression of vascular endothelial growth factor(VEGF) mRNA and protein derived from epithelial cells were detected respectively by in situ hybridization and ELISA. RESULTS: 1. Under hypoxia, EPO mRNA was expressed intensely in epithelial cells from NP and IT, and there was no significant difference between both of them. This result suggested that EPO might be regarded as a hypoxic mark. 2. The ability of producing VEGF mRNA increased with cytokines stimulation, especially under hypoxia. Protein level of VEGF from epithelial cells of NP and IT increased with cytokines stimulation, especially in hypoxia and was time-dependent. CONCLUSION: Epithelial cells actively produce vast VEGF under hypoxia. The VEGF induced by hypoxia of the mucosa in middle meatus is of importance in the formation of nasal polyps(NP) in early stage, which may be the major cause of NP formation in middle meatus.  相似文献   
36.
目的 对胸腰段脊柱脊髓,马尾神经损伤患者的外科治疗及几种内固定方法的疗效进行探讨。方法 对166例患者的治疗进行回顾分析。该组患者中椎体爆裂性骨折37例,椎体压缩骨折超二分之一109例,椎体骨折脱位14例,多节段或跳跃骨折6例,脊髓损伤按Frankel分级,A级59例,B级46例,C级42例,D级19例,治疗采用后路减压复位122例,前路减压复位,髂骨植骨融合44例。结果 术后123例获3-18个月随访,随访患者中随4例RF钉断裂,5例Harrington上钩脱落,6例棍断裂,其余患者内固定稳固,脊髓,马尾神经恢复,除35例仍为A级外,余脊髓神经功能恢复1-3个级别。结论 各种不同内固定可保持或增强脊柱的稳定,胸腰段脊柱脊髓损伤的外科治疗应根据骨折类型,脊髓及马尾神经损伤程度选择手术入路及内固定材料。  相似文献   
37.
目的:观察肝癌形成过程中明胶酶表达(蛋白及mRNA水平)的动态变化,探索明胶酶在肝癌生长浸润中的作用。方法:应用免疫组化法、明胶酶谱法和RT-PCR法对大鼠肝癌形成过程中各期明胶酶表达情况进行观察,并与正常对照组进行比较分析。结果:正常肝组织及肝硬化组织内明胶酶有表达,肝癌形成后主要在癌细胞内表达;明胶酶原在正常肝组织中有低表达,诱癌过程中呈持续增高趋势;明胶酶-2mRNA与其酶蛋白表达趋向一致。结论:在肝癌形成过程中明胶酶转录和翻译水平均呈持续增高趋势。  相似文献   
38.
AIM: To report the clinical and oncological data of patients operated on for rectal cancers 3-5 cm from the AV over a 10 year period, including the Sphincter preservation (SP) rate. METHODS: We reviewed medical records of 304 patients with rectal cancers 3-5 cm from the AV who underwent surgical resection from January 1991 through December 2000. The 10 years were divided into three periods based on the introduction of new surgical techniques, specifically, ultralow anterior resection (ULAR) with double stapling in March 1994 and ULAR with coloanal anastomosis in April 1997. The rates of SP, complications and patient survival during these periods were compared. RESULTS: The SP rate increased significantly over the 10 years, from 16.4% in period I (January 1991-February 1994), to 53.0% in period II (March 1994-March 1997), to 86.5% in period III (April 1997-December 2000) (p<0.001). Over time, the age of the patients increased (p=0.004), the length of the distal resection margin became shorter (p=0.005), and the rate of lymph node metastasis increased (p=0.016). The factors significantly influencing SP were the period (p<0.001) and the distance from the AV (p<0.001). Over time, morbidity did not increase, and overall and disease free survival rates did not decrease. In contrast, the overall survival of N2 cases significantly increased over time (p=0.0492). CONCLUSION: Over 10 years, the SP rate in rectal cancers 3-5 cm from the AV was significantly increased by the introduction of the double stapling and coloanal anastomosis techniques. These surgical methods, however, had no effect on morbidity, disease free survival and overall survival rates.  相似文献   
39.
本实验用~3H-TdR掺入,液体闪烁测量法测定细胞DNA期外合成的方法,测定了小鼠和大鼠的肠淋巴结细胞、人和大鼠外周血淋巴细胞、S-180V肿瘤细胞等经紫外线照射后的UDS,观察到UDS掺入量随辐照度增加而增加。在同一辐照剂量下,以小鼠肠淋巴结细胞的UDS值最高,其次是人外周血淋巴细胞和S-180V肿瘤细胞,而大鼠外周血淋巴细胞和肠淋巴结细胞最低。  相似文献   
40.
PGA指数和透明质酸在诊断慢性乙肝肝纤维化中的价值   总被引:1,自引:0,他引:1  
目的:寻找一种简便实用的诊断慢性乙型肝炎纤维化的方法。方法:以78例经肝穿刺病理证实的慢性乙型肝炎为对象,测定并比较了由PT、GGT、ApoA1组成的PGA指数和HA、LN、PⅢP、C-IV与肝内纤维化程度(S)和炎症活动度(G)的关系。结果:(1)LN、PⅢP、C-IV在轻度慢性乙肝时无明显升高,在中度慢性乙肝时明显高于正常,但与轻度慢性乙肝无差异,而PGA指数和HA不仅在轻度慢性乙肝时显著升高,而且在轻中度间差异明显.因重度慢性乙肝和活动性肝硬化时,五项指标均显著增高。(2)在G2-4期,HA、LN、PⅢP、C-IV均明显高升,但在G1期,只有PGA指数高于正常,且各期间差异显著。(3)在S1-2期,只有PGA指数、HA、C-IV明显上升,但C-IV的上升幅度远低于PGA指数和HA。(4)加以PGA>4.5或HA>200μg/L作为判断临界值,则两者判断肝纤维化的敏感性均>94%,精确性>91%,特异性>86%,如两者结合,则分别达到98.3%、95.2%和96.4%。结论:PGA指数和HA均是反映慢性乙型肝炎患者肝内纤维化程度的良好指标,两者联合检测则可达到最大的价值效益比。  相似文献   
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