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41.
Percutaneous transluminal balloon angioplasty (PTA) is being currently used in patients with coronary artery disease. Laser irradiation (LI) has been effective in vaporizing atherosclerotic plaques. The purpose of this work was twofold: to compare PTA and LI techniques in the recanalization of experimental obstructive arterial lesions, and to evaluate the possibility of reducing the failures and local complications and increasing the success rate of PTA by the combined use of LI. Atherosclerotic iliac stenoses were induced in 27 rabbits; lesions were evaluated angiographically before and after intervention and were studied histologically and by electron microscopy. Argon-ion LI delivered through microlens-tip optic fibers reduced the stenotic area from 64.2 +/- 21.8% to 40.3 +/- 10.7% (n = 10, P less than .01) and PTA from 60.7 +/- 15.9% to 30.4 +/- 7.7% (n = 9, P less than .01). However, percentage reduction was higher in PTA-treated stenoses (48.4 +/- 10.1% vs 34.5 +/- 13.5%, P less than .0125). In eight more rabbits, low power LI (4.55 +/- 1.25 J) was delivered after PTA in dilated segments. Post-PTA LI further decreased stenoses (from 31.2 +/- 7.8% to 29.1 +/- 8.1%, P less than .0125); laser-irradiated segments showed diffuse carbonization of the disrupted intimal layer. The normalized transtenotic pressure gradient decreased significantly in all groups: LI reduced the gradient from .40 +/- .25 to .17 +/- .07 (P = .005); PTA from .37 +/- .14 to .11 +/- .04 (P = .001); LI after PTA from .40 +/- .16 to .12 +/- .06 (P = .001). Thus, LI is effective (less than PTA) in relieving experimental atherosclerotic stenoses and seems useful when combined with PTA.  相似文献   
42.
Abstract: In order to evaluate the level of evidence of factors influencing the survival of reconstructions, systematic reviews of the relevant literature were prepared by a group of rapporteurs. The review papers were circulated to the members of the group before the conference and formed the basis for group and panel discussions. Subsequently, modifications were added to the review papers, and suggestions for consensus statements concerning the following topics were prepared and again critically reviewed in the group and in the plenum: Impact of (i) periodontal disease on the survival of tooth-supported reconstructions, (ii) post-surgical factors as supportive therapy on the survival of implant supported reconstructions, (iii) technical and/or biological complications on the survival of different types of reconstructions, (iiii) material choice for reconstructions on the survival of single crowns and fixed dental prostheses.  相似文献   
43.
目的:探讨全肺放疗治疗肺转移癌的价值.方法:1999年3月~2003年5月我院肿瘤科收治24例双肺多发肺转移癌患者,均给予全肺放疗.现对这些患者的临床资料进行总结分析.结果:本组放疗结束时转移瘤CR率为37.5%(9/24),PR率为50.0%(12/24),有效率(PR+CR)达87.5%.原发肿瘤为鼻咽癌、乳腺癌、肝癌、结直肠癌的中位生存期分别为13.5、22.0、10.5月、8.5月.1~2级放射性肺炎发生率为25.0%(6/24);3级为16.7%(2/24);4~5级为0.结论:恶性肿瘤肺多发转移可以采用全肺放疗+局部小野补量治疗,尤其适用于原发肿瘤对放疗中高度敏感、化疗无效的患者,可获得较好疗效.毒副作用可耐受.  相似文献   
44.
The changes in spike activity of single neurons of the compact part of the substantia nigra, evoked by nucleus caudatus stimulation under conditions of long-term registration of the single and multiple, isolated and combined actions of GABA, GABA-amide, glutamine, and ethanolamine-O-sulfate (EOS) were studied in albino rats. Inhibition of poststimulus activity under GABA action was recorded and the inhibitory effect of GABA-amide was revealed. Primary excitatory and subsequent inhibitory effects of glutamine in combination with EOS were shown. The subsequent administration of bacterial melanin, synthesized by a mutant culture of Bacillus thuringiensis (BT-M) evoked a clear-cut and prolonged excitatory reaction during all the combined actions of GABA, GABA-amide, glutamine, and EOS. Preliminary administration of BT-M abolished the inhibitory poststimulus effects of GABA, GABA-amide, and EOS, as well as glutamine-induced excitation.  相似文献   
45.
目的 探讨中国人过氧化物酶体增殖物激活受体γ(PPARγ)基因外显子6 C161T多态性与糖皮质激素性骨质疏松症(GIO)的相关关系。方法 应用聚合酶链反应-限制性片段长度多态性(PCR-RELP)方法测定208例正常健康人(Ⅰ组)、168例非GIO患者(Ⅱ组)和104例GIO患者(Ⅲ组)PPARγ基因外显子6 C161T的基因型。应用双能X线骨密度仪(DEXA)测定股骨、腰椎等部位的骨密度。 结果 外显子6 C161T有CC、CT、TT 3种基因型。GIO组CC基因型频率显著低于正常对照组;CT和TT基因型频率显著高于正常对照组。非GIO组、应用激素组(GIO组+非GIO组)与正常对照组比较,各基因型频率差异均无统计学意义。正常对照组C161T的CC基因型组各部位的骨密度有高于CT和TT基因型组的趋势,但差异无统计学意义。非GIO组和GIO组C161T的CC基因型组腰椎的骨密度明显高于CT和TT基因型组 (P < 0.05),分别为非GIO组CC型(1.04±0.17) g/cm2,CT+TT型(1.02±0.07) g/cm2;GIO组CC型(0.94±0.12) g/cm2,CT+TT型(0.83±0.08) g/cm2。经年龄、体重指数等因素校正后,差异仍有统计学意义(P < 0.05)。 结论 PPARγ基因C161T基因型在正常人和应用激素患者之间无明显差异,它可能与肾小球肾炎的发病无关。C161T基因型在GIO组和正常对照组之间差异有统计学意义,它可能与糖皮质激素性骨质疏松症的发病有关。PPARγ基因C161T多态性与应用糖皮质激素患者腰椎的骨密度有关。等位基因C可能是骨量的保护因子,它可能与应用糖皮质激素后骨量的丢失有关。  相似文献   
46.
Objective To evaluate the association of 2616c/T polymorphism in iron regulatory protein 2(IRP2)gene with Alzheimer disease(AD)and Vascular dementia(VD).Methods In this study,281 patients with AD,60 with VD,and 285 normal aged were recruited.The 2616C/T polymorphism in IRP2 gene was analyzed by using polymerase chain reaction-restriction fragment length polymorphism.And the cognitive function was assessed with the Mini-Mental State Examination(MMSE).Results (1)No significant difieFences were demonstrated in IRP2 genotype or allele frequencies between AD patients and controls(χ2=2.46,P=0.292;χ2=2.17,P=0.141 respectively).However,when AD patients were stratified by disease severity.the frequency of T allele carriers in the moderate to severe AD patients was 78.0%,significantly higher than that in controls(69.8%;χ2=4.106,P<0.05).Logistic regression analysis demonstrated that the age-,sex-and ApoE-adiusted OR of modcrate to severe AD patient with T allele was 1.62(95% CI=1.03-2.54).The frequency of T allele carriers or T allele in VD patients was higher than that of controls,but the difference was not statistically significant(P>0.05).(2)The frequency of tit genotype or T allele in the moderate to severe AD patients was significantly higher than that in mild AD patients(25.8%vs.12.5%,χ2=5.477,P<0.05;51.9%vs.40.3%,χ2=5.803,P<0.05 respectively).(3)MMSE scores of the AD patients with TT genotype was significantly lower than ones with CC or CT genotype(P=0.028;P=0.014 respectively).Conclusion The 2616C/T polymorphism in the IRP2 gene is possibly associated with moderate to severe AD.but not associated with VD.And the TT genotype may be a risk factor for cognitive impairment of patients with AD in Chinese Han.  相似文献   
47.
海带多糖的抗辐射作用与脾细胞凋亡   总被引:12,自引:0,他引:12  
目的 :探讨海带多糖 (LJP)抗辐射作用及其可能机理。方法 :将Wistar大鼠随机分为正常对照组、模型组和 4个不同剂量LJP实验组 ,灌胃 1 0d后行一次性γ射线辐射 ,每只 9.0Gy ,1 8h后测定各组大鼠体液免疫、细胞免疫、非特异性免疫相关指标及脾淋巴细胞凋亡率。结果 :模型组免疫指标明显低于正常对照组 ,LJP各组能显著调节辐射损伤大鼠的免疫功能 ,脾淋巴细胞凋亡率显著低于模型组 ,并呈现明显的剂量 效应关系。结论 :LJP抗辐射作用的可能机理之一是抑制免疫细胞凋亡  相似文献   
48.
目的:观察和探讨两种印模技术对单个前牙烤瓷冠颈缘外观的改善效果。方法:40位患者用简易印模技术制取印模,制作93件镍铬合金烤瓷瓷冠,设为实验组,另35位患者以常规印模技术制取印模,制作71件镍铬合金烤瓷瓷冠,设为对照组。观察两组戴冠当时与两年后的颈缘适合性、颜色、牙龈形态与健康情况。结果:试验组有98%的合金瓷冠具有优良的边缘适合性,仅2件(2%)出现颈缘黑线,与对照组相比有显著差异(P<0.05)。结论:简易印模技术能更好的保证工作区模型的准确度,从而有效地改善了镍铬合金烤瓷冠颈缘的美观与龈组织的健康。  相似文献   
49.
目的 探讨三氧化二镍(Ni2O3)对人肺成纤维细胞(human lung fibroblasts,HLF)的DNA损伤作用以及Na2SeO3的保护作用。方法 应用单细胞凝胶电泳(single cell gel electrophoresis,SCGE)检测DNA损伤。结果 Ni2O3 处理HLF细胞4 h,SCGE检测出DNA损伤程度高于对照组,差异有显著性(P<0.01)。而Ni2O3 Na2SeO3 处理组DNA损伤程度低于Ni2O3 组,差异有显著性(P<0.01)。结论 硒可抑制镍诱导的人肺成纤维细胞的DNA损伤。  相似文献   
50.
三维重建单(双)靶点定向置管引流术治疗高血压壳核出血   总被引:1,自引:0,他引:1  
目的回顾性分析三维重建单(双)靶点定向置管引流术治疗高血压壳核出血的疗效,验证该方法的有效性和可行性。方法将133例壳核脑出血病人的CT定位扫描资料输入计算机工作站,对血肿进行三维重建,根据血肿量的大小和形状设计1~2个靶点和引流管路径。应用立体定向技术将引流管(外径5mm,内径3mm)送至颅内预定靶点,术中应用10ml注射器轻柔抽吸血肿液化部分,术后将尿激酶(1~2万IU)注入血肿腔内,夹闭引流管2h后自然引流,每12h重复1次。复查CT证实剩余血肿量为最初的10%~15%时拔除引流管。结果平均置管1.5 d(1~3d),平均血肿排空率92.8%。术后1个月病死率6.0%,远期随访(平均22个月)病死率11.3%,优良率74.4%。结论该方法治疗高血压壳核脑出血,血肿排空较彻底,疗效可靠,尤其适用于血肿量较大(>25ml)且形态不规则的颅内血肿。  相似文献   
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