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61.
目的:探讨经鼻持续气道正压通气(nCPAP)治疗,对阻塞性睡眠呼吸暂停综合征(OSAS)合并高血压患者动态血压的影响。方法:22例男性患者行多导睡眠图(PSG)监测及动态血压检查确诊为OSAS合并高血压的患者,观察nCPAP治疗前后患者动态血压、多导睡眠图等多项指标变化。结果:nCPAP治疗后患者PSG参数明显改善:睡眠时最低SaO_2从(71.0±12.3)%上升到(91.7±7.3)%(P<0.01);RDI显著降低;同时24小时血压明显下降,治疗前血压(16.5±1.6/11.6±2.3Kpa),治疗后血压(13.7±1.5/9.3±1.4Kpa)(P<0.01)。结论:经鼻持续气道正压通气治疗阻塞性睡眠呼吸暂停综合征,不但可以纠正患者的呼吸暂停,改善临床症状,而且可能降低患者的血压。 相似文献
62.
63.
土鳖虫水提物对实验性高脂血症大鼠血管内皮和内皮素的影响 总被引:19,自引:0,他引:19
目的研究土鳖虫水提物对高脂血症大鼠血管内皮和内皮素 (ET)的影响。方法建立高脂血症大鼠模型 ,测定血浆ET的浓度 ,并应用内皮细胞铺片和免疫组化相结合的方法 ,在大鼠主动脉内皮细胞铺片上 ,计数内皮细胞和ET阳性细胞并定量分析ET的合成。结果实验第 80d ,与正常组比较 ,高脂组血浆ET显著增高 (P <0 .0 1) ;内皮铺片显示内皮细胞数量增多 ,排列紊乱 ,胞核大小和染色深浅不一 ,ET阳性细胞率显著升高 (P <0 .0 1)。土鳖虫中、高剂量组血浆ET水平和ET阳性细胞率显著降低 (P <0 .0 5~ 0 .0 1)。结论土鳖虫水提物能保护血管内皮 ,减少ET的合成与释放 相似文献
64.
Effect of lonizing Radiation on the Expression of p16,CyclinD1 and CDK4 in Mouse Thymocytes and Splenocytes 总被引:4,自引:0,他引:4
OBJECTIVE: To investigate the effect of ionizing radiation on the expression of p16, CyclinD1, and CDK4 in mouse thymocytes and splenocytes. METHODS: Fluorescent staining and flow cytometry analysis were employed for the measurement of protein expression. RESULTS: In time course experiments, it was found that the expression of p16 protein was significantly increased at 8, 24, and 48 h for thymocytes (P < 0.05, P < 0.01, and P < 0.05, respectively) and at 24 h for splenocytes (P < 0.05) after whole body irradiation (WBI) with 2.0 Gy X-rays. However, the expression of CDK4 protein was significantly decreased from 8 h to 24 h for thymocytes (P < 0.05-P < 0.01) and from 8 h to 72 h for splenocytes (P < 0.05-P < 0.01). In dose effect experiments, it was found that the expression of p16 protein in thymocytes and splenocytes was significantly increased at 24 h after WBI with 1.0, 2.0, and 4.0 Gy (P < 0.05-P < 0.01), whereas the expression of CDK4 protein was significantly decreased with 2.0 Gy for thymocytes (P < 0.05) and 0.5-6.0 Gy for splenocytes (P < 0.05-P < 0.01). Results also showed that the expression of CyclinD1 protein decreased markedly in both thymocytes and splenocytes after exposure. CONCLUSION: The results indicate that the expression of p16 protein in thymocytes and splenocytes can be induced by ionizing radiation, and the p16-CyclinD1/CDK4 pathway may play an important role for G1 arrest of thymocytes induced by X-rays. 相似文献
65.
Anticancer Drug Resistance of HeLa Cells Transfected With Rat Glutathione S-transferase pi Gene 总被引:3,自引:0,他引:3
Cao W Zuo J Meng Y Wei Q Shi ZH Ju LM Fang FD 《Biomedical and environmental sciences : BES》2003,16(2):157-162
Objective To establish a cytologic expressing system of rat glutathione S-transferase pi (GST-pi) cDNA for detecting the resistance of HeLa cells to anticancer drugs. Methods The assessment was made with various anticancer drugs (adriamycin, mitomycin, cisplatinum and vincristine) that showed different cytotoxicities in transfectant HeLa cells with pSV-GT containing rat GST-pi cDNA (HeLa/pSV-GT) or control pSV-neo (HeLa/pSV-neo). Expression levels of GST-pi mRNA in HeLa/pSV-GT and HeLa/pSV-neo were measured by in situ hybridization using Digoxin-labelled cDNA probe. Results HeLa/pSV-GT expressed significantly high degree of GST-pi mRNA, whereas both HeLa/pSV-neo and HeLa cells had very low expression. Cytotoxicities of HeLa/pSV-GT and HeLa/pSV-neo with 4 anticancer drugs were measured by MTT assay. Drug concentrations for yielding 50% inhibition (IC50) in HeLa/pSV-GT by adriamycin, mitomycin and cisplatinum were 70.13μg/mL, 10.95μg/mL and 16.52μg/mE respectively. In contrast, IC50 in HeLa/pSV-neo was 10.34μg/mL, 7.48μg/mL and 13.70μg/mE respectively. The cytotoxicities of vincristine on both HeLa/pSV-GT and HeLa/pSV-neo were not significantly different. Conclusions Our findings suggest that HeLa/pSV-GT containing rat GST-pi cDNA is resistant to some anticancer drugs due to overexpression of GST-pi. Also, HeLa/pSV-GT cell line could serve as a useful cytogenetic model for further research. 相似文献
66.
反相高效液相色谱法测定发酵液中梅岭霉素 总被引:1,自引:0,他引:1
目的:建立了发酵液中梅岭霉素的定量测定方法。方法:反相高效液相色谱法,Hypersil-C_(18)柱(4 mm×125mm,5μm),流动相为乙腈-水(78:22),流速1.2mL·min~(-1),检测波长238 nm,室温测定。结果:在1O.2~163.2μg·mL~(-1)范围内梅岭霉素浓度与峰面积呈良好线性关系,r=0.999 7,回归方程为Y=25.44X+2.72。样品的日间 RSD≤1.8%,高中低浓度样品的日内RSD≤2.5%(n=8)。平均回收率为96.9%(n=8,RSD<3.0%)。结论:本方法快速、准确、简便、稳定,为定量分析提供了可靠的依据。 相似文献
67.
Time-dependent astroglial changes after gamma knife radiosurgery in the rat forebrain 总被引:11,自引:0,他引:11
OBJECTIVE: Using an experimental rat model and a clinically relevant treatment dose, we performed gamma knife radiosurgery to define the hyperacute radiation effects in normal rat forebrain, the time dependence of the astrocytic reaction, and the participation of astrocytes in the healing process after single-dose gamma radiation injuries. METHODS: Seventy-one rats underwent radiosurgical treatment (4-mm collimator) of the caudate-putamen nucleus (single-fraction maximal dose of 100 Gy) and were killed at times ranging from 3 hours to 90 days. Serial cryostat brain sections were processed with the immunohistochemical avidin-biotin complex technique, using anti-glial fibrillary acidic protein as the primary antibody (to identify astrocytes). RESULTS: Vascular changes, including endothelial hyperplasia and vessel wall thickening, were identified as the earliest postradiation manifestations and continued throughout the observation period. Astrocytes reacted to the radiation injury with hyperplasia and hypertrophy. At earlier time points (3-24 h), proliferation was the predominant reaction. The expression of glial fibrillary acidic protein in the proliferating and hypertrophic astrocytes formed an initial peak in the adjacent corpus callosum 3 days after radiosurgery and peaked within the target site between 14 and 30 days. Astrocytic proliferation and hypertrophy were also observed in distant cortices (frontal, parietal, insular, and piriform cortices) and in the hippocampus. No necrosis was observed less than 30 days after irradiation. By Day 90, necrotic lesions with a mean diameter of 4 mm were identified, with glial scar at their peripheries. Astrocytic morphological features varied according to the distance from the necrosis. The irradiated side contained more glial fibrillary acidic protein-containing cells than did the nonirradiated contralateral side. CONCLUSION: During the early phase after radiation, vasculopathy was the first morphological change and may serve as the initiating factor for subsequent changes. Reactive astrocytes appeared not only at the target site but also in the surrounding regions; the severity of injury was determined by the distance from the target. 相似文献
68.
旋转手法对椎动脉血流平均速度的影响 总被引:4,自引:0,他引:4
目的 观察手法治疗椎动脉型颈椎病的经颅多普勒 (TCD)变化 ,从血流动力学角度探讨手法治疗的作用机制。方法 将 82例椎动脉型颈椎病患者随机分成手法治疗组 4 0例与常规治疗组 4 2例 ,治疗前及治疗后检查TCD ,观察手法治疗对椎动脉型颈椎病患者的血流平均速度的影响。结果 ① 82例患者治疗前椎基底动脉血流平均速度均明显低于正常参考值范围(P <0 .0 5 )。TCD异常率为 76 % ( 6 2 /82 )。②治疗后两组椎基底动脉血流速度均有改善。手法治疗组比常规治疗组椎动脉血流速度改善更明显 (P <0 .0 5 )。结论 手法治疗可以改善椎动脉型颈椎病椎基底动脉的血流速度。 相似文献
69.
Bachiller Burgos J Varo Solís C Báez JM Estudillo F Juárez Soto A Soto Delgado M Beltrán Aguilar V González Moreno D Sánchez Bernal C Rodríguez-Rubio F 《Actas urologicas espa?olas》2000,24(8):673-676
The existence of a vesical diverticulum in the context of a congenital connective tissue disorder such as Ehlers-Danlos syndrome led us to consider the possibility of a relationship. Four types of diverticula can be found in the literature: congenital, acquired, iatrogenic and syndrome-associated. Within the later, Ehlers-Danlos syndromes type IV and IX, even type V, are associated to the existence of vesical diverticula. The potential spontaneous rupture of the diverticulum is a typical feature, as well as post-surgery relapse. The attitude towards such diverticula should be one of watchful waiting, and simple, plasty-free diverticulectomy on the bladder's neck is indicated when performing a surgical procedure. 相似文献