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11.
Zeng X  He H  Yang J  Yang X  Wu L  Yu J  Li L 《Journal of ethnopharmacology》2008,118(3):485-494
AIM: Cardiac infarction is one of the main causes of death in both developing and developed countries over past decades. Currently available approaches for treating patients with this disease are not satisfactory. Traditional Chinese medicines have been increasingly paid attention to. The aim of this study was to characterize the dynamic protective effects of Guanxin No. 2 decoction (GX II) on cardiac dysfunction combined with the blood viscosity and myocardial hypertrophy parameters in myocardial infarction (MI) rats. METHODS: Male Sprague-Dawley rats (180-200 g) were randomly divided into three groups: sham-operated, coronary artery ligation (CAL), and CAL plus GX II (GX II, 10.0 g raw materials/kg/d, bid, p.o.). The experiment was carried out at 4 time points as the 3rd, 7th, 14th, and 28th day after ligation. RESULT: It was found that on the one hand, GX II could significantly improve the heart function, and remarkably decrease infarct size and inhibit ventricular remodeling. On the other hand, GX II showed some unique effects such as angiogenesis which was induced in the left ventricular tissue. This result was consistent with the finding of an augmented vascular endothelial growth factor (VEGF) expression in this area. CONCLUSIONS: The studies demonstrated that GX II exerted extensively beneficial cardioprotective effect on CAL rats, it might stimulate angiogenesis of ischemic region to compensate blood supply to the heart via upregulated VEGF expression.  相似文献   
12.
目的探讨患者体内肺癌细胞Ku80蛋白含量与其对顺铂敏感性的相关性。方法收集肺癌患者胸腔积液中的肺癌细胞进行体外原代培养,通过传代进行纯化和扩增后进行实验。体外药敏试验采用CCK-8法测定肺癌细胞对顺铂的敏感性,获得各样本的半数抑制浓度(IC50)。利用Western blot法测定各样本细胞内Ku80蛋白含量。分析Ku80蛋白含量与顺铂敏感性的相关性。结果非小细胞肺癌(NSCLC)组IC50为(4.40±3.39)mg/L,小细胞肺癌(SCLC)组IC50为(1.02±0.54)mg/L,二者比较差异有统计学意义(P0.001)。NSCLC组Ku80蛋白相对含量为0.80±0.45,而SCLC组为0.48±0.25,二组之间比较差异有统计学意义(P0.05)。通过相关性分析得到肺癌患者Ku80含量与IC50呈正相关(r=0.618,P0.001)。结论 NSCLC患者Ku80基因表达高于SCLC患者,可能与NSCLC对化疗敏感性差有关。肺癌细胞Ku80蛋白含量与其对顺铂敏感性呈负相关。Ku80蛋白含量可作为预测肺癌患者以铂类为基础的化疗敏感性的候选指标。  相似文献   
13.
We prove a localization principle for directional maximal operators in Lp(ℝn), with p > 1. The resulting bounds, which we conjecture hold for the largest possible class of directions, imply Lebesgue-type differentiation of integrals over tubes that point in the given directions.  相似文献   
14.
In this retrospective study, we evaluated and compared the efficacy and toxicities of maximal androgen blockade (MAB) versus castration alone in Chinese patients with advanced prostate cancer. From 1996 to 2004, 608 patients with advanced prostate cancer were included in the study. Patients were retrospectively divided into two groups according to different therapeutic regimens. Of the 608 patients, 300 patients were treated with MAB (castration plus nonsteroidal antiandrogens) and the remaining 308 were treated with castration alone. The 2- and 5-year overall survival rates of these patients were 73.7% and 56%, respectively. Multivariate analysis showed that, in patients with metastatic prostate cancer, MAB was associated with not only the improvement of progression-free survival (PFS) (increased by 10 months) but also a 20.6% reduction in mortality risk compared with castration alone. In contrast, the efficacy of MAB was not superior to castration alone for patients with nonmetastatic prostate cancer. Interestingly, among patients with MAB, those using bicalutamide had a longer PFS than those using flutamide; this was especially so in patients with metastatic prostate cancer. Almost all of the toxicities due to the hormone therapy were mild to moderate and manageable. To conclude, in China, hormone therapies, including MAB and castration alone, have been standard treatments for advanced prostate cancer. For patients with nonmetastatic prostate cancer, castration alone might be adequately practical and efficient. In patients with metastatic prostate cancer, however, MAB has superior efficacy over castration alone. It is clear that MAB should be considered the first-line standard treatment for patients with metastatic prostate cancer.  相似文献   
15.
目的研究米非司酮对乳腺癌细胞系MCF-7和T47D的增殖抑制作用。方法采用四甲基偶氮唑盐(MTT)法检测米非司酮对乳腺癌细胞系MCF-7和T47D的半数抑制浓度(IC50)。不同浓度米非司酮(0.25、2.5、25和50μmol/L)分别处理人乳腺癌细胞系MCF-7和T47D1、2、3d后,观察细胞形态变化,以及检测各组细胞生长曲线。结果米非司酮对乳腺癌MCF-7和T47D细胞均有抑制作用,其抑制率均随着米非司酮浓度的增加而变化,存在明显的量效关系。通过对两种细胞抑制率(IR)值直线回归分析,米非司酮对MCF-7细胞的IC50为51.21μmol/L,对T47D细胞的IC50为54.29μmol/L。形态学观察发现,各组细胞体积变小,细胞间的链接消失,细胞内明显有黑色小颗粒聚集。25和50μmol/L浓度米非司酮对MCF-7乳腺癌细胞株生长抑制作用明显,特别是50μmol/L干预24h后在高倍镜下可见明显的核质浓缩。结论米非司酮对病理分型、激素受体型不同的乳腺癌MCF-7和T47D细胞均具有抑制增殖的作用,并呈时间和剂量依赖效应。  相似文献   
16.
BackgroundHypometria is a clinical motor sign in Parkinson's disease. Its origin likely emerges from basal ganglia dysfunction, leading to an impaired control of inhibitory intracortical motor circuits. Some neurorehabilitation approaches include movement imitation training; besides the effects of motor practice, there might be a benefit due to observation and imitation of un-altered movement patterns. In this sense, virtual reality facilitates the process by customizing motor-patterns to be observed and imitated.ObjectiveTo evaluate the effect of a motor-imitation therapy focused on hypometria in Parkinson's disease using virtual reality.MethodsWe carried out a randomized controlled pilot-study. Sixteen patients were randomly assigned in experimental and control groups. Groups underwent 4-weeks of training based on finger-tapping with the dominant hand, in which imitation was the differential factor (only the experimental group imitated). We evaluated self-paced movement features and cortico-spinal excitability (recruitment curves and silent periods in both hemispheres) before, immediately after, and two weeks after the training period.ResultsMovement amplitude increased significantly after the therapy in the experimental group for the trained and un-trained hands. Motor thresholds and silent periods evaluated with transcranial magnetic stimulation were differently modified by training in the two groups; although the changes in the input–output recruitment were similar.ConclusionsThis pilot study suggests that movement imitation therapy enhances the effect of motor practice in patients with Parkinson's disease; imitation-training might be helpful for reducing hypometria in these patients. These results must be clarified in future larger trials.  相似文献   
17.
The prognostic value of ST-segment depression during maximalexercise test performed in the third to fourth week after acutemyocardial infarction (AMI), was studied in 126 consecutivepatients with no evidence of previous myocardial infarction,unstable angina pectoris or severe heart failure. All patientson average increased their pressure-rate product by 2.6 andno complications occurred. Within the first year of follow-up,major cardiac events occurred in 9 patients (20%), and werefatal in 6 (13%), of the 46 patients who developed ST-segmentdepression during exercise. Only 3 major cardiac events (4%)occurred in the 80 patients without exercise induced ST-segmentdepression. Depression of the ST-segment on maximal exercisewas a significant predictor of subsequent cardiac events inthese survivors of first AMI.  相似文献   
18.
PurposeTo investigate the pharmacokinetics (PK) and early effects of conventional transarterial chemoembolization (TACE) using sorafenib and doxorubicin on tumor necrosis, hypoxia markers, and angiogenesis in a rabbit VX2 liver tumor model.Materials and MethodsVX2 tumor-laden New Zealand White rabbits (N = 16) were divided into 2 groups: 1 group was treated with hepatic arterial administration of ethiodized oil and doxorubicin emulsion (DOX-TACE), and the other group was treated with ethiodized oil, sorafenib, and doxorubicin emulsion (SORA-DOX-TACE). Animals were killed within 3 days of the procedure. Levels of sorafenib and doxorubicin were measured in blood, tumor, and adjacent liver using mass spectrometry. Tumor necrosis was determined by histopathological examination. Intratumoral hypoxia-inducible factor (HIF) 1α, vascular endothelial growth factor (VEGF), and microvessel density (MVD) were determined by immunohistochemistry.ResultsThe median intratumoral concentration of sorafenib in the SORA-DOX-TACE group was 17.7 μg/mL (interquartile range [IQR], 7.42–33.5 μg/mL), and its maximal plasma concentration (Cmax) was 0.164 μg/mL (IQR, 0.0798–0.528 μg/mL). The intratumoral concentration and Cmax of doxorubicin were similar between the groups: 4.08 μg/mL (IQR, 3.18–4.79 μg/mL) and 0.677 μg/mL (IQR, 0.315–1.23 μg/mL), respectively, in the DOX-TACE group and 1.68 μg/mL (IQR, 0.795–4.08 μg/mL) and 0.298 μg/mL (IQR, 0.241–0.64 μg/mL), respectively, in the SORA-DOX-TACE group. HIF-1α expression was increased in the SORA-DOX-TACE group than in the DOX-TACE group. Tumor volume, tumor necrosis, VEGF expression, and MVD were similar between the 2 groups.ConclusionsThe addition of sorafenib to DOX-TACE delivered to VX2 liver tumors resulted in high intratumoral and low systemic concentrations of sorafenib without altering the PK of doxorubicin.  相似文献   
19.
目的:探讨中国北方平原地区汉族男子脑型肌酸激酶(CKB)基因多态性与耐力训练效果的关联性。方法:102名无训练史的健康男子进行18周有氧耐力训练,测试训练前后的最大摄氧量、跑节省化(RE)各指标。用PCR-RFLP法分析CKB基因启动子上rs3759582和rs3759584两位点的单核苷酸多态性。结果:二个多态位点均符合H-W平衡,不存在强的连锁关系;训练后rs3759582位点AA基因型最大摄氧量变化率、跑节省化变化率与AC基因型组间均无显著性差异(P>0.05);训练后rs3759584位点TT基因型△RE/VO2、△RE/rVO2、△RE/HR和△RE/VE显著低于CT和CC基因型(P<0.05),但是CC基因型频率仅为3%。结论:CKB基因的rs3759582多态性不是预测个体耐力训练敏感性的基因标记;rs3759584与个体的耐力训练敏感性相关,但需加大样本进一步确认。  相似文献   
20.
孟鲁司特联合布地奈德福莫特罗治疗重度哮喘的临床研究   总被引:1,自引:0,他引:1  
目的观察孟鲁司特联合布地奈德福莫特罗治疗重度哮喘的疗效。方法对136例重度哮喘患者进行随机对照研究,分为治疗组68例,对照组68例,治疗组用盂鲁司特联合布地奈德福莫特罗治疗,对照组吸入布地奈德福莫特罗治疗。结果两组治疗4周后,治疗组疗效优于对照组。结论孟鲁司特联合布地奈德福莫特罗治疗重度哮喘的疗效优于单用布地奈德福莫特罗治疗。  相似文献   
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