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1.
茶多酚抗氧化和抑菌机制的研究   总被引:10,自引:0,他引:10  
茶多酚是一种新兴的天然的抗氧化剂,以抑菌、抗氧化能力强和安全性高等优点,可代替人工合成的防腐剂添加于肉制品中,改善肉制品的质量。本文重点介绍了茶多酚防腐机制的研究进展。  相似文献
2.
桃红四物汤治疗原发性痛经实验研究   总被引:6,自引:0,他引:6  
目的:观察桃红四物汤治疗痛经的作用,探讨其机制。方法:①观察桃红四物汤对热板法所致昆明种雌性小鼠疼痛的影响。②复制缩宫素致Wistar雌性大鼠痛经模型,观察桃红四物汤不同剂量对大鼠扭体次数、扭体发生率、血浆β-内啡肽(β-endorphin,β—EP)及子宫组织前列腺素F2a(prostaglandin F2a,PGF2a)的影响。结果:与模型组比较,桃红四物汤各剂量组小鼠痛阈均显著提高(P〈0.01),痛经大鼠30rain内扭体次数显著减少(P〈0.01),扭体发生率降低;大鼠子宫组织PGF2。含量显著降低(P〈0.01);与模型组比较,桃红四物汤高、中剂量组大鼠血浆β—EP含量显著升高(P〈0.05),与田七痛经胶囊组及阿司匹林组比较,差异无显著性(P〉0.05)。结论:①桃红四物汤有明显的镇痛作用;②有调节大鼠血浆β—EP及子宫组织前列腺素分泌的作用。  相似文献
3.
李耀辉  刘冬梅  盛继文  阎芳  张仕状 《医学争鸣》2009,30(12):1103-1106
目的:研究无蹼壁虎药物成分的抗肿瘤效果.方法:提取壁虎中有效药物成分,甲基噻唑蓝(MTT)法测定肿瘤细胞的生长,观察壁虎药用成分的抗肿瘤效果;BALB/e小鼠CT-26小鼠结肠癌造模分组,抗肿瘤活性成分组按0.25,0.10,0.05mg/kg剂量,阳性对照组为内皮抑素6mg/kg,阴性对照组为同体积生理盐水,每日一次性侧腋部皮下注射,自由摄食摄水,第15日称体质量,脱颈处死,解剖皮下肿瘤,称湿质量,计算肿瘤抑制率.结果:从壁虎提取得到的成分对肿瘤生长具有良好的抑制作用且与时间和剂量呈相关性;体外抑瘤实验,抑制率最高可达45.50%;小鼠体内抑瘤实验,肿瘤抑制率为67.24%.结论:壁虎含抗肿瘤有效药物成分,具有开发利用的潜力.  相似文献
4.
Background Radiofrequency ablation (RFA) followed by transarterial chemoembolization (TACE) for unresectable primary liver cancer (PLC) has not been widely discussed. In this study, the outcome of the combination of RFA with TACE was retrospectively evaluated. Methods From May 2003 to March 2008, 127 consecutive PLC patients with a median age of 56.4+8.8 years underwent RFA plus TACE. All patients were deemed to have unresectable PLC based on their tumor characteristics. The maximal diameter of the tumor was between 1.5 cm and 10.0 cm. Twenty-six cases with small (〈3.0 cm), 33 with medium (3.1-5.0 cm), and 68 with large (〉5.0 cm) tumors were included in this study. RFA was performed using a RITA Medical Systems expandable electrode device, which was followed by first-time TACE administration one to two months later. Results Technical success of RFA was achieved in all 127 patients with no severe treatment-related complications. RFA was performed percutaneously in 16 (13.5%) cases, by laparoscopic approach in 19 (15.7%), and through laparotomy in the remaining 92 (72.4%). RFA response was classified as complete ablation in 48 cases, nearly complete ablation in 28, and partial ablation in 51. The total 1-, 2-, and 3-year survival rates after RFA were 83.1%, 55.7%, and 43.7%, respectively. The survival rates at 3 years were 78.6%, 28.1%, and 0 for complete ablation, nearly complete ablation, or partial ablation groups, respectively. Three-year disease-free survival rates for the complete ablation and nearly complete ablation groups were 50.3% and 21.3%, respectively. RFA response and liver function were significant variables influencing survival time as analyzed using the Cox regression model. Conclusion RFA could be the first-line exterminate treatment for unresectable PLC, and TACE following RFA may assist in eradicatinq the peripheral viable tissue and micro-metastasis.  相似文献
5.
目的探讨灯盏花素注射液对家兔缺血再灌注损伤肠系膜微循环的保护作用。方法将15只家兔随机分为模型组、预防组、治疗组,在BI2000医学图像分析系统下观察并记录缺血30 min和再灌注30 min时家兔肠系膜微动脉管径(DA)、微静脉管径(DV)、血液流态(BFS)、微血管数目(CV)和红细胞聚集(EA)。结果缺血30 min时,各组与缺血前比较,预防组BFS权分值增加(P<0.05),其他4项指标变化不显著;模型组、治疗组DA、DV缩小(P<0.05),BFS权分值增加(P<0.001),CV减少、EA明显(P<0.01);与模型组比较,预防组DA舒张、EA明显(P<0.05),BFS权分值减小、CV增多(P<0.01),治疗组微循环变化不显著;预防组与治疗组比较DA舒张、CV增多(P<0.05),BFS权分值减小、EA明显(P<0.01)。再灌注30 min时各组与其缺血前比较,模型组DA、DV缩小、CV减少、EA明显(P<0.01),BFS权分值增加(P<0.001),预防组CV增多、BFS权分值减小(P<0.05),治疗组微循环变化不显著;与模型组比较,预防组DA、DV舒张、BFS权分值减小、CV增多、EA明显(P<0.01),治疗组DA、DV舒张(P<0.05),BFS权分值减小、CV增多、EA明显(P<0.01);预防组与治疗组比较,DV舒张(P<0.05),BFS权分值减小(P<0.01)。结论灯盏花素注射液对家兔缺血再灌注时肠系膜微循环损伤有一定的保护作用。  相似文献
6.
目的 比较马尔尼菲青霉菌酵母相和霉菌相蛋白质组表达差异.方法 应用表面增强激光解吸离子化飞行时间质谱技术(SELDI)检测马尔尼菲青霉菌酵母相和霉菌相的蛋白质谱.用PBSIIC型蛋白质芯片阅读机读取数据并进行分析.结果 在WCX2芯片上共捕获75个蛋白峰,其中10个蛋白质在酵母相高表达,3个蛋白质在霉菌相高表达.相对分子质量为2900和3151蛋白质仅在酵母相表达,13 151和13 285蛋白质仅在霉菌相表达.结论 SELDI技术可以检测出马尔尼菲青霉菌霉菌相和酵母相表达的小分子蛋白质差异.  相似文献
7.
住院患者抗生素使用情况分析   总被引:3,自引:0,他引:3  
目的了解解放军第309医院抗生素的合理使用情况。方法利用医院药房软件系统提取2009年4月15日至2009年5月15日全部在院1333例住院患者的临床用药数据,统计各科室抗生素使用率、抗生素的种类及其使用率和抗生素的联用情况。结果抗生素的使用率为76.52%;抗生素联用者占抗生素总人数的27.5%。其中二联占22.3%,三联占3.9%。结论抗生素使用不合理主要表现在使用率偏高、用药起点高和联合用药不合理。  相似文献
8.
Background Enhanced external counterpulsation (EECP) improves ischemia in patients with refractory angina pectoris but the mechanism remains unclear. To explore the mechanisms of EECP action, we detected progenitor cells presenting any of the following markers CD34^+, CD29^+, and CD106^+.
Methods Growth cytokines-mediated progenitor cell mobilization and associated angiogenesis potential were assessed in a porcine model of hypercholesterolemia. Twenty-four male domestic swines were randomly assigned to 4 groups: normal diet (control, n=6), hypercholesterolemic diet (CHOL, n=-6), hypercholesterolemic diet with administration of recombinant human granulocyte colony-stimulating factor (rhG-CSF) (rhG-CSF, n=6), and hypercholesterolemic diet with EECP treatment (EECP, n=6). EECP was applied 2 hours every other day for a total of 36 hours. Serum levels of vascular endothelial growth factor (VEGF) and granulocyte colony-stimulating factor (G-CSF), peripheral blood progenitor cell counts, level of regional angiogenesis, and expression of VEGF and stromal cell derived factor l a (SDF-1α) in porcine myocardium were assessed, respectively.
Results A porcine model of hypercholesterolemia-induced arteriosclerosis was successfully established. There was no significant difference in serum levels of VEGF among the four groups. The serum levels of G-CSF in the EECP group increased significantly at week 15 and week 18 ((38.3±5.6) pg/ml at week 15 vs (26.2±3.7) pg/ml at week 12, P 〈0.05, and (46.9±6.1) pg/ml at week 18 vs (26.2±3.7) pg/ml at week 12, P 〈0.01). The serum levels of G-CSF in group 3 increased also significantly after receiving rhG-CSF injection for five days ((150±13.9) pg/ml at week 18 vs (24.8±5.4) pg/ml at week 12, P 〈0.01). Compared to other groups and other time points, progenitor celt counts increased significantly after 2-hour EECP treatment (108±13 vs 26±6 per 10^5 leukocytes, P 〈0.01), but not at week 18. The progenitor cell counts also increased significantly after subcutaneous injection of rhG-CSF for five days compared to the week 12 (baseline) (180±21 vs 25±7 per 10s leukocytes, P 〈0.01). There was no significant difference among the four groups at other time points. Moreover, the expression of VEGF and SDF-1α and the level of regional angiogenesis in myocardium increased significantly in both EECP and rhG-CSF groups.
Conclusions The results demonstrated that EECP could facilitate angiogenesis in the myocardium of atherosclerotic swines by increasing endogenous G-CSF, inducing an enhanced mobilization of progenitor cells and augmenting myocardial expression of VEGF and SDF-1α.  相似文献
9.
Background Atrial fibrillation is a common arrhythmia and a major risk factor for ischaemic stroke. We investigated the prevalence of atrial fibrillation and its relation to age, gender and underlying heart disease in patients aged 60 years and over who died during hospitalization.
Methods Between 1955 and 2005, 1519 autopsies of in-hospital deaths in Beijing Hospital were performed. Among them, 540 cases met criteria of age ≥60 years and full clinical history including electrocardiogram, echocardiogram, myocardial perfusion images and detailed cardiac pathology records from autopsy.
Results Atrial fibrillation occurred in 193 of 540 patients and prevalence increased with age (10.5% in patients younger than 60 years, 39.6% (80-89 years) and 54.8% (≥ 90 years)) being higher in patients with underlying heart disease than without heart disease (P 〈0.0001). Coronary artery disease (CAD), congestive heart failure, cardiac valve dysfunction and chronic renal failure were associated with a higher prevalence of atrial fibrillation (P 〈0.001). CAD with anterior myocardial infarction or left anterior descending artery disease was also associated with an increased prevalence of atrial fibrillation (P 〈0.05). Following autopsy, clinical misdiagnosis of CAD increased with age and missed clinical diagnosis of CAD decreased with age. Multivariate Logistic regression analysis revealed independent predictors of atrial fibrillation: age (OR=1.335, 95% CI: 1.114-1.600, P 〈0.0001), underlying heart disease (OR=2.019, 95% CI: 1.244-3.278, P 〈0.005), chronic heart failure (OR=1.873, 95% CI: 1.272-2.757, P 〈0.005), mitral regurgitation (OR=2.163, 95% CI: 1.093-4.278, P 〈0.05) and mitral stenosis (OR=33.575, 95% CI: 2.852-395.357, P 〈0.05).
Conclusions A high prevalence of atrial fibrillation was found in Chinese patients ≥60 years who died in hospital, especially when associated with underlying heart disease. The independent risk factors of atrial fibr  相似文献
10.
加味丹参饮预处理对心肌细胞内钙超载的延迟保护作用   总被引:3,自引:1,他引:2  
目的观察加味丹参饮预处理对心肌细胞内钙超载的延迟保护作用。方法将培养72h的大鼠心肌细胞随机分6组,空白组正常培养;正常血清对照组加50%大鼠血清培养;含药血清组加50%含加味丹参饮的药物血清培养;缺氧再给氧组予缺氧3h,再给氧1h。缺氧预处理组、加味丹参饮预处理组分别给予缺氧预处理、加味丹参饮预处理,24h后再予缺氧3h,给氧1h。结果缺氧再给氧组乳酸脱氢酶(LDH)、肌酸激酶(CK)及细胞内钙离子浓度显著升高(P<0.01),缺氧预处理和加味丹参饮预处理组LDH、CK及细胞内钙离子浓度显著低于缺氧再给氧组(P<0.01),与空白组、血清对照组和含药血清对照组相似(P>0.05)。结论加味丹参饮预处理的延迟保护作用可防止心肌细胞内钙离子超载,从而发挥细胞保护作用。  相似文献
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