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91.
92.
The chemical and radio toxicity of 125-5-iodo-2-deoxyuridine (125IUDR) on 870127T human lung cancer (HLC) cells grown in tissue cultures and the quantitative analysis of the distribution and fate of 125IUDR-labeled 870127T HLC cells in nude mice were evaluated. After 870127T HLC cells were plated and 125IUDR was added to the dishes at levels ranging from 0.1 µCi/ml to 5.0 µCi/ml of media, the growth rate of the cells for 24h was similar to that of non-labeled cells. Nude mice were given intravenous injections of 125IUDR labeled 870127T HLC cells and killed at various intervals ranging from 5 min to 24 h after injection. Organs were collected, processed, and monitored. The lung contained most of the tumor cells at all intervals and the number of tumor cells in the lung decreased gradually post-injection. The tumor cells died rapidly, and only about 1.5% of all cell survived after 24 h post-injection. This study confirmed that very few surviving tumor cells are needed to cause metastasis.  相似文献   
93.
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   
94.
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   
95.
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   
96.
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   
97.
Vascular Ehlers–Danlos syndrome (vEDS) is a hereditary connective tissue disorder (HCTD) characterized by arterial dissection/aneurysm/rupture, sigmoid colon rupture, or uterine rupture. Diagnosis is confirmed by detecting heterozygous variants in COL3A1. This is the largest Asian case series and the first to apply an amplification-based next-generation sequencing through custom panels of causative genes for HCTDs, including a specific method of evaluating copy number variations. Among 429 patients with suspected HCTDs analyzed, 101 were suspected to have vEDS, and 33 of them (32.4%) were found to have COL3A1 variants. Two patients with a clinical diagnosis of Loeys–Dietz syndrome and/or familial thoracic aortic aneurysm and dissection were also found to have COL3A1 variants. Twenty cases (57.1%) had missense variants leading to glycine (Gly) substitutions in the triple helical domain, one (2.9%) had a missense variant leading to non-Gly substitution in this domain, eight (22.9%) had splice site alterations, three (8.6%) had nonsense variants, two (5.7%) had in-frame deletions, and one (2.9%) had a multi-exon deletion, including two deceased patients analyzed with formalin-fixed and paraffin-embedded samples. This is a clinically useful system to detect a wide spectrum of variants from various types of samples.  相似文献   
98.
99.
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   
100.
Individual congeners of polychlorinated biphenyls (PCBs), including the highly toxic non-ortho coplanar 3,3,4,4-tetrachlorobiphenyl (IUPAC No. 77), 3,3,4,4,5-pentachlorobiphenyl (IUPAC No. 126), and 3,3,4,4,5,5-hexachlorobiphenyl (IUPAC No. 169), and their mono- and di-ortho analogs, have been identified and quantified in the blubber, liver, and muscles of three female common porpoise Phocoena phocoena collected from the Puck Bay (inner Gulf of Gdask, Poland) in 1989–1990, to elucidate actual concentrations and toxic potential. The total 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalent for 13 coplanar PCBs in blubber was 1,500±470 pg/g wet wt. 2,3,4,4,5-Pentachlorobiphenyl (IUPAC No. 118) was the most contributing individual and occupied between 57 and 67% in total toxic equivalent of coplanar PCBs in blubber, while 2,2,4,4,5,5-hexachlorobiphenyl (IUPAC No. 153), 2,3,3,4,4-pentachlorobiphenyl (IUPAC No. 105) and 2,2,3,4,4,5-hexachlorobiphenyl (IUPAC No. 138) comprised between 9.5–14, 7.6–11.5, and 7.2–11.0%, respectively (totally 82–95%), and 2,3,3,4,4,5-hexachlorobiphenyl (IUPAC No. 156) was absent. A potentially most toxic non-ortho PCB members such as 3,3,4,4,5-pentachlorobiphenyl, 3,3,4,4,5,5-hexachlorobiphenyl and 3,3,4,4-tetrachlorobiphenyl were only minor contributors, altogether occupying between 1.0 and 14.5% in total TEQ of coplanar PCBs. Concentrations of total PCBs in lipids of the blubber ranged from 26 to 47 g/g and were comparable or lower than reported earlier for common porpoises from the Baltic Sea, North Sea, and North Atlantic by other authors.  相似文献   
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