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排序方式: 共有4144条查询结果,搜索用时 15 毫秒
41.
胫骨平台骨折的手术治疗 总被引:4,自引:0,他引:4
目的:探讨胫骨平台骨折的最佳治疗方法。方法:回顾性分析我院1997年1月至2000年12月收治的69例胫骨平台骨折手术患,骨折类型按Schatzker分型,其中Ⅰ型12、Ⅱ型19例、Ⅲ组10例、Ⅳ6例、Ⅴ8例、Ⅵ14例。除Ⅰ型采用经皮穿刺空心螺钉内固定外,其余各型采用切开复位支持钢板内固定,原则上塌陷>0.5cm一律采用自体髂骨植骨。结果:58例患随访,平均随访15个月(6-37个月),功能评价采用Hohl膝关节功能评分法,优良率达87.93%,结论:胫骨平台骨折宜手术治疗,手术方法根据不同的骨折类型而异。 相似文献
42.
I型内皮素受体反义寡聚核苷酸抑制VSMC增殖及内膜增生 总被引:4,自引:1,他引:3
目的 观察 型内皮素受体 (ETA)反义寡核苷酸(ODN)对血管平滑肌细胞 (VSMC)增殖和内膜增生的抑制作用 .方法 1细胞培养 :取家兔主动脉中膜消化后培养传代 ,经抗 α- actin鉴定后使用第 4~ 6代传代细胞 ;2人工合成ODN:经 Genbank检索筛选 ,合成含 18bp ETA- ODN片段 ,再对 5 端硫代修饰以增加稳定性 ,同时行地高辛标记以检测反义片段的细胞膜穿透性 ;3 MTT分光光度法检测 ETA-ODN对 VSMC增殖的抑制作用 ;4运用放射受体结合分析法 (1 2 5I- ET- 1)了解 ODN对 ETA蛋白表达的抑制作用 ,以探讨其反义作用 ;5兔颈动脉空气干燥模型在体研究 ODN对血管内膜增生的抑制作用 :应用 F- 12 7凝胶载体携带 ETA-ODN(3.0μmol· L- 1 )导入血管周围 ,术后不同时间观察增生内膜相对厚度 .结果 ODN于培养后 12 h进入细胞内 ,并逐渐增加 ;15 μmol· L- 1 ETA- ODN对 VSMC增殖具有抑制作用 ,2 4h后即有显著作用 ;ETA- ODN对 ETA表达亦有明显的抑制作用 ,表现为 CPM于 2 4h逐渐减少 ;ETA- ODN导入后 ,血管增生内膜相对厚度减少 .结论 ETA- ODN以浓度和时间依赖方式抑制 ETA蛋白表达以及 VSMC的增殖 ;反义寡核苷酸是通过反义机制实现对 ETA蛋白和 VSMC增殖的抑制作用 相似文献
43.
目的:探讨肿瘤微血管与前列腺癌生长,转移的关系。方法:应用免疫组化技术结合放射免疫测定检测第Ⅷ因子相关抗原和前列腺特异性抗原(PSA)在19例前列腺癌和40例前列腺增生中的表达和平均值及其相关关系。结果:前列腺癌组织中微血管密度(MVD)和PSA值明显高于前列腺增生,转移性前列腺癌MVD和PSA值高于非转移性前列腺癌,前列腺癌MVD与PSA呈正相关,结论:血管形成与前列腺癌的发生,发展和转移密切相关,肿瘤的增长和转移有赖于肿瘤血管的生成。 相似文献
44.
职业性慢性放射病临床诊断及预后 总被引:1,自引:0,他引:1
目的:探讨慢性放射病(以下简称慢放病)的诊断、治疗及预后。方法:以受照剂量,临床症状,造血功能,T淋巴细胞百分率,染色体畸变率对30例慢性放射损伤患者进行综合分析判断,对其中11例慢放病用胸腺肽治疗并追踪观察10年。结果:慢放病患者受照剂量超过2Sv,白细胞下降伴有几髓造血功能障碍,T淋巴细胞百分率下降,染色体畸变率显著上升。胸腺肽能改善临床症状,显著提高细胞免疫功能。慢放病各项指标恢复依时间顺序为:T淋巴细胞百分率(2年),临床症状(3.5年),造血功能(5~8年),染色体畸变率(10年)。结论:受照剂量是误断慢放病的重要依据;白细胞总数、骨髓造血功能改变是诊断的关键;T淋巴细胞百分率、染色体畸变率可作为鉴别诊断指标。慢放病是一种可以恢复的职业性疾病,胸腺肽治疗有助于慢放病的恢复。 相似文献
45.
46.
Shin-ichi Terao Gen Sobue Yoshio Hashizume Noriko Shimada Terunori Mitsuma 《Acta neuropathologica》1994,88(2):137-142
A quantitative analysis was made of the myelinated fibers in the lateral corticospinal tract (LCST) at the levels of the 6th cervical, 7th thoracic and 4th lumbar spinal segments in 20 patients between 19 and 90 years old, and who died of non-neurological diseases. The diameter frequency histograms of myelinated fibers of LCST showed a bimodal pattern with a sharp peak of the small myelinated fibers and broad slope of the large myelinated fibers. The ratio of small fiber to large fiber densities was significantly higher in the 6th cervical (P<0.05) and 4th lumbar segments (P<0.01) than in the 7th thoracic segments. The density of small myelinated fibers was significantly lowered with advancing age (P<0.050.001), while that of large myelinated fibers was not significantly decreased in the aged patients, although it showed a slight age-dependent declining tendency. Age-dependent decline of small fiber density was more prominent in the cervical and lumbar segments. Retraction of the axon-collaterals from large-diameter myelinated fibers, which are abundant in the cervical and lumbar segments, may contribute to the age-related diminution of the small myelinated fibers in the LCST.Part of this work was supported by grants from the Ministry of Welfare and Health of Japan, and a grant from Uehara Memorial Research Foundation 相似文献
47.
The forward problem of a new medical imaging system is analysed in this study. This system uses magnetic excitation to induce currents inside a conductive body and measures the magnetic fields of the induced currents. The forward problem, that is determining induced currents in the conductive body and their magnetic fields, is formulated. For a general solution of the forward problem, the finite element method (FEM) is employed to evaluate the scalar potential distribution. Thus, inhomogeneity and anisotropy of conductivity is taken into account for the FEM solutions. An analytical solution for the scalar potential is derived for homogeneous conductive spherical objects in order to test FEM solutions. It is observed that the peak error in FEM solutions is less than 2%. The numerical system is used to reveal the characteristics of the measurement system via simulations. Currents are induced in a 9x9x5 cm body of conductivity 0.2 S m(-1) by circular coils driven sinusoidally. It is found that a 1 cm shift in the perturbation depth reduces the field magnitudes to approximately one-tenth. In addition, the distance between extrema increases. Further simulations carried out using different coil configurations revealed the performance of the method and provided a design perspective for a possible data acquisition system. 相似文献
48.
Manometric Evidence of Improved Early Gastric Stasis by Erythromycin after Pylorus-preserving Pancreatoduodenectomy 总被引:3,自引:0,他引:3
Matsunaga H Tanaka M Takahata S Ogawa Y Naritomi G Yokohata K Yamaguchi K Chijiiwa K 《World journal of surgery》2000,24(10):1236-1242
Gastric stasis is a frequent complication of pylorus-preserving pancreatoduodenectomy (PPPD). We demonstrated that it might be attributable to delayed recovery of phase III activity of the gastric migrating motor complex due to low concentrations of plasma motilin caused by resection of the duodenum. Leucine 13-motilin is effective for treating gastric stasis, but it is not yet available for clinical use. Whether erythromycin would improve early gastric stasis after PPPD was tested clinically and by manometry. A manometric tube assembly and a gastrostomy tube were inserted in the stomach of 10 patients at PPPD for pressure recording from the gastric antrum and jejunum and for gastric juice drainage, respectively. After baseline recording, erythromycin 5 mg/kg was given intravenously on day 14 and saline as a placebo on day 17 every 4 hours four times a day. The daily volume of gastric juice output and the gastric motility index were measured. The mean period until the return of gastric phase III was 31 +/- 1 days. Erythromycin significantly increased the gastric motility index from 7.9 +/- 1.3 mmHg to 15.7 +/- 1.8 mmHg (p = 0.0005), whereas saline did not (7.2 +/- 1.6 mmHg to 6.5 +/- 1.2 mmHg; p = 0.21). Erythromycin significantly decreased the gastric juice output from 1,080 +/- 190 ml to 738 +/- 199 ml (p < 0.0001), but the saline injections did not (1,064 +/- 174 ml to 1,115 +/- 189 ml; p = 0.35). Erythromycin, a universally available motilin agonist, is a safe, effective, potent drug for the treatment of early gastric stasis after PPPD. 相似文献
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