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81.
Percutaneous transluminal renal angioplasty: initial and long-term results   总被引:2,自引:0,他引:2  
Renal artery stenosis in 201 patients with hypertension was treated with percutaneous transluminal renal angioplasty (PTRA). A total of 213 procedures were performed as treatment of 262 separate stenosis. The stenosis was caused by atherosclerosis in 134 cases and by fibromuscular dysplasia (FMD) in 52 cases; the cause was indeterminate in 27 cases. Of the 213 procedures, 172 were successful or resulted in improvement, for a technical success rate of 80.8%. The initial clinical results could be evaluated in 210 cases; cure or improvement was achieved in 80%. There were 23 cases in which neither technical nor clinical success was achieved. Data on the remaining 187 cases were the basis of this long-term follow-up study. The cumulative patency rate at 5 years was 80% in the atherosclerosis group, 89% in the FMD group, and 74% in the indeterminate group. The mortality was less than 1%. Because spasm occurred in 33 cases, causing an infarction in ten instances, antispasmodic medication seems warranted. These long-term results indicate that PTRA is the treatment of choice in patients with renovascular hypertension.  相似文献   
82.
Aronchick  JM; Epstein  DM; Gefter  WB; Miller  WT 《Radiology》1988,168(3):675-678
Five patients with chronic traumatic diaphragmatic hernia presented with symptoms of acute intestinal obstruction and unilateral pleural effusion. In each case, infarcted herniated abdominal structures were found at surgery. The presence of an ipsilateral pleural effusion is an important radiographic sign, which may indicate strangulation in patients with chronic traumatic diaphragmatic hernia.  相似文献   
83.
A method to decrease the intensity of fat by reversal of the section-select gradient is demonstrated. This technique takes advantage of the chemical shift in section location.  相似文献   
84.
Using referred samples to study predictors of disease produces statistical problems that reduce the likelihood of obtaining statistically significant results even when a substantial relationship is present between a risk factor and a disease. The present paper refers to these problems as disease based spectrum (DBS) bias. DBS bias is present when subjects are directed into or excluded from the study sample according to their disease status. For example, healthy individuals are excluded from and diseased individuals are directed into referred samples. Therefore, DBS bias is present in referred samples. Examples from the literature on Type A behavior and coronary artery disease (CAD) are presented to illustrate how DBS bias reduces statistical associations. The results of the current research indicate DBS bias has reduced the association between Type A behavior and CAD in a number of studies reported in recent years. In addition, the present article discusses techniques for assessing and controlling for DBS bias.  相似文献   
85.
参三七皂甙Rg1对实验性血栓形成的影响及其机制探讨   总被引:10,自引:0,他引:10  
徐皓亮  刘宛斌 《药学学报》1997,32(7):502-506
用大鼠动静脉血栓形成模型,研究参三七皂甙Rg1抗血栓作用。结果表明,参三七皂甙Rg1可明显降低实验性血栓形成,对大鼠血浆纤溶系统亦有明显作用,可升高血浆中组织纤溶酶原激活物(tPA)活性和活性型tPA百分比,降低组织纤溶酶原激活物抑制剂(PAI)活性。同时利用培养大鼠血管内皮细胞实验,发现Rg1可以剂量依赖性提高血管内皮细胞一氧化氮(NO)释放。提示Rg1抗血栓作用与增强纤溶系统活性,促进血管内皮NO释放有关  相似文献   
86.
This study examines the use of the forced expiratory technique (FET) as a means of improving the uniformity of radionuclide aerosol ventilation images in patients with excess sputum production. Ventilation images are objectively classified by two computer derived indices to characterize the degree of radioaerosol clumping and overall uniformity. In a series of twenty five patients with a long-standing history of daily sputum production, images acquired before and after forced expiration and again after a second ventilation immediately following FET showed no significant change in either index. The results obtained do not provide evidence to support the routine use of FET in conjunction with radioaerosol scintigraphy. The method of image classification correlates well with a visual assessment of image uniformity and has general application.  相似文献   
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4-间氨基酚-4去甲表鬼臼醚诱导K562细胞凋亡   总被引:1,自引:0,他引:1  
目的:鬼臼毒素具有抗炎作用,为限制其对机体产生不良反应,探讨经过结构改造的4-间氨基酚-4去甲表鬼臼醚对K562细胞生长抑制及诱导凋亡情况。方法:实验于2004-03/2005-01在兰州医学院完成。①实验材料:4-间氨基酚-4去甲表鬼臼酯由兰州大学应用有机化学国家重点实验室田暄教授惠赠,纯度98%。依托铂甙(连云港恒瑞药业产品,批号04060121,20g/L)临用前以5%二甲亚砜稀释至5g/L。K562细胞由兰州大学中药新药临窗前研究重点实验室传代保种。②细胞生长抑制率检测:取K562细胞,离心后调整浓度为1×108L-1,以100μL等量接种于96孔培养板。4-间氨基酚-4去甲表鬼臼醚组分别加入0.313,0.625,1.25,2.5,5,10,20,40mg/L的4-间氨基酚-4去甲表鬼臼醚药液10μL;依托铂甙组分别加入以上8种终浓度的依托铂甙药液10μL;正常对照组加入等量的溶媒;空白对照组不加细胞和任何药物,只加入等量的完全培养液。采用噻唑蓝法检测药物与细胞作用24,48,72h时K562细胞的生长抑制率。③细胞超微结构观察:取K562细胞,离心后调整浓度为1×109L-1,以2mL等量接种于24孔培养板。4-间氨基酚-4去甲表鬼臼醚组加入2.5mg/L的4-间氨基酚-4去甲表鬼臼醚药液200μL,正常对照组加入等量的溶媒。制作超薄切片,用醋酸双氧铀、柠檬酸铅染色,透射电镜观察细胞形态及细胞质、细胞核的变化。④细胞周期及凋亡检测:取K562细胞,离心后调整浓度为1×108L-1,以2mL等量接种于24孔培养板。4-间氨基酚-4去甲表鬼臼醚组分别加入1.25,2.5,5,10,20mg/L的4-间氨基酚-4去甲表鬼臼醚药液200μL,正常对照组加入等量的溶媒。在流式细胞仪上检测细胞周期,用Multicycle软件计算凋亡细胞百分率。结果:①4-间氨基酚-4去甲表鬼臼醚抑制K562细胞生长情况:在0.313~20mg/L范围内,其对K562细胞的抑制作用随浓度升高而增强,具有量效关系,同时抑制率随着作用时间的延长而升高,具有时效关系;超过20mg/L时抑制作用逐渐下降。依托铂甙对K562细胞的抑制情况与4-间氨基酚-4去甲表鬼臼醚类似。②细胞超微结构:正常对照组K562细胞核形状规则,核膜清晰可见,内质网丰富,内含大量线粒体,细胞表面微绒毛多,染色体分布于核中央。4-间氨基酚-4去甲表鬼臼醚组K562细胞出现明显的凋亡特征,微绒毛消失,细胞浆固缩,染色体凝集为团块状分布于核膜边缘,细胞内出现大量空泡,线粒体和内质网减少,细胞周围出现凋亡小体。③细胞周期及凋亡情况:1.25,2.5,5,10,20mg/L4-间氨基酚-4去甲表鬼臼醚作用24h,分别有19.4%,34.8%,34.0%,6.9%,4.5%的K562细胞发生凋亡,G0/G1期和S期K562细胞减少,于G2/M期明显增多。正常对照组凋亡率仅为0.3%。结论:①4-间氨基酚-4去甲表鬼臼醚能够抑制K562细胞的生长,呈时效、量效关系。②4-间氨基酚-4去甲表鬼臼醚可诱导K562细胞凋亡。  相似文献   
90.
Although mutational inactivation of E‐cadherin (CDH1) is the main driver of invasive lobular breast cancer (ILC), approximately 10–15% of all ILCs retain membrane‐localized E‐cadherin despite the presence of an apparent non‐cohesive and invasive lobular growth pattern. Given that ILC is dependent on constitutive actomyosin contraction for tumor development and progression, we used a combination of cell systems and in vivo experiments to investigate the consequences of α‐catenin (CTNNA1) loss in the regulation of anchorage independence of non‐invasive breast carcinoma. We found that inactivating somatic CTNNA1 mutations in human breast cancer correlated with lobular and mixed ducto‐lobular phenotypes. Further, inducible loss of α‐catenin in mouse and human E‐cadherin‐expressing breast cancer cells led to atypical localization of E‐cadherin, a rounded cell morphology, and anoikis resistance. Pharmacological inhibition experiments subsequently revealed that, similar to E‐cadherin‐mutant ILC, anoikis resistance induced by α‐catenin loss was dependent on Rho/Rock‐dependent actomyosin contractility. Finally, using a transplantation‐based conditional mouse model, we demonstrate that inducible inactivation of α‐catenin instigates acquisition of lobular features and invasive behavior. We therefore suggest that α‐catenin represents a bona fide tumor suppressor for the development of lobular‐type breast cancer and as such provides an alternative event to E‐cadherin inactivation, adherens junction (AJ) dysfunction, and subsequent constitutive actomyosin contraction. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.  相似文献   
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