首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   28168篇
  免费   2156篇
  国内免费   1057篇
耳鼻咽喉   60篇
儿科学   557篇
妇产科学   418篇
基础医学   3412篇
口腔科学   353篇
临床医学   2664篇
内科学   3498篇
皮肤病学   306篇
神经病学   1045篇
特种医学   577篇
外国民族医学   4篇
外科学   1168篇
综合类   5251篇
现状与发展   1篇
预防医学   2438篇
眼科学   321篇
药学   5584篇
  21篇
中国医学   2662篇
肿瘤学   1041篇
  2024年   45篇
  2023年   307篇
  2022年   450篇
  2021年   942篇
  2020年   827篇
  2019年   773篇
  2018年   727篇
  2017年   967篇
  2016年   1004篇
  2015年   916篇
  2014年   1547篇
  2013年   2068篇
  2012年   1447篇
  2011年   1722篇
  2010年   1331篇
  2009年   1114篇
  2008年   1180篇
  2007年   1194篇
  2006年   1222篇
  2005年   1051篇
  2004年   979篇
  2003年   896篇
  2002年   737篇
  2001年   686篇
  2000年   592篇
  1999年   434篇
  1998年   454篇
  1997年   429篇
  1996年   406篇
  1995年   414篇
  1994年   394篇
  1993年   387篇
  1992年   338篇
  1991年   294篇
  1990年   251篇
  1989年   252篇
  1988年   184篇
  1987年   207篇
  1986年   137篇
  1985年   405篇
  1984年   306篇
  1983年   253篇
  1982年   233篇
  1981年   203篇
  1980年   148篇
  1979年   102篇
  1978年   97篇
  1977年   76篇
  1976年   66篇
  1975年   44篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
61.
本文研究结果表明,应用无血清培养体系对鼠中孕期乳腺组织细胞(COMMA-1D细胞)、鼠乳腺肿瘤细胞(FUKU细胞)以及CD8F1细胞的原代培养中。BM Matrigel是一良好的细胞附着和细胞生长的促进剂,而Ⅳ型胶原、昆布胺酸和Vitrogen 100对上述细胞的附着和生长也有一定的作用。BM Matrigel和昆布胺酸对FUKU细胞的克隆产率也有显著的促进作用,而昆布胺酸应用方便,价格较低,更适于在实验研究中推广应用。  相似文献   
62.
目的总结地高辛血药质量浓度监测方法,寻求最适的测定方法。方法对近年来国内外与地高辛监测相关的文献进行检索综述分析。结果地高辛血药浓度测定方法很多,常用方法主要有:FPIA、酶免疫分析法、RIA、CLIA、乳胶免疫抑制法、干化学法、HPLC法等。结论通过比较分析其中RIA、CLIA、EIA和HPLC MS 4种方法更好。  相似文献   
63.
Recently, Korean people are consuming seaweeds almost 3.5 times more now than three decades ago. It is well known that seaweeds contain lots of soluble dietary fiber in addition to micronutrients such as β-carotene, iodine and some bioactive components. Seaweeds are considered to be effective for preventing chronic diseases including obesity, diabetes mellitus, atherosclerosis, cancer or constipation. This study was conducted to investigate the effect of seamustard intake on body weight gain, blood glucose level and lipid profiles in rats fed diets with different energy nutrient composition. Male Sprague-Dawley rats (average initial weight 103.7 g) were divided into groups for two experiments as follows; Control, M2.5 & M5 groups (Exp. I) and M5, M10, HCM5, HCM10, HFM5 & HFM10 groups (Exp. II). The rats were fed diet and water ad libitum for 4 weeks. In general, there was no significant difference in blood glucose and triglyceride concentration among groups. In Exp. I, serum LDL-cholesterol level of rats fed diet with 5% seamustard powder (M5) was significantly lower than that of control group, while HDL-cholesterol level, TC/LDL ratio and weight of adrenal gland were higher. In Exp. II, food intake, body weight gain and EER of high fat diet with 10% seamustard group (HFM10) were the lowest among groups. Except gastrocnemius muscle, all organ weights of HFM10 group were the lowest. Fecal cholesterol excretion and serum LDL-cholesterol concentration of HFM10 group were the highest, while serum HDL-cholesterol level was the lowest among groups. Interestingly, HDL-cholesterol concentration was the highest in HCM5 group among groups. From these results, it was suggested that seamustard intake might be more effective for body weight control, but not for improving blood lipid profiles in high fat diet than in high carbohydrate diet.  相似文献   
64.
Endoneurial hypoxia and a high frequency of closed capillaries have been found in chronic experimental diabetes and human diabetic sural nerve, respectively. These findings have led to the hypothesis that the pathogenesis of diabetic neuropathy is due to endoneurial hypoxia. To evaluate the role of endoneurial hypoxia in experimental diabetic neuropathy, the effects of supplementation and deprivation of oxygen on peripheral nerve lipid biosynthesis were studied in normal control and streptozotocin-induced diabetic rats. Defective lipid biosynthesis in diabetic nerve was partially prevented by oxygen supplementation. When normal rats were placed in a hypoxic chamber, lipid abnormalities similar to those observed in diabetic nerves were demonstrated in the absence of changes in nerve free sugars. These findings suggest that endoneurial hypoxia may underlie some key biochemical abnormalities encountered in experimental diabetic neuropathy.  相似文献   
65.
AIM: To evaluate the cause of elevated prostate-specific antigen (PSA) in patients with transrectal needle biopsy negative for prostate cancer. METHODS: Serum PSA concentration, prostate volume, and pathologic findings were examined in 223 patients with negative biopsy for prostate cancer. The degree of prostate inflammation was determined by the extent and degree of inflammation shown by biopsy specimens and is expressed as an inflammation score (range: 0-36). RESULTS: A significant correlation was found between PSA concentration and prostate total volume (P=0.0001). Prostate chronic inflammation showed no correlation with PSA concentration (P=0.485, F=0.488). After allocating patients to normal PSA (4 ng/mL) groups, we found that serum PSA concentrations in both groups were predominantly affected by prostate total volume. CONCLUSIONS: An increase in prostate volume appears to be the major contributor to a high serum PSA concentration in patients with negative biopsy for prostate cancer. However, in contrast to previous reports, there was no correlation between the degree of prostate chronic inflammation and serum PSA concentrations.  相似文献   
66.
血肌酐值法预测地高辛个体化给药方案   总被引:1,自引:0,他引:1  
在地高辛常规监测中,用血肌酐值法预测个体化药动学参数和给药方案。结果表明,84例病人的地高辛药物动力学参数预测值为,CL76±21ml/(kg·h),Vd7.05±1.20L/kg,T1/266±7h。预测的个体化剂量为3.1±0.9μg/(kg·d),预测的稳态血药浓度(C_(ss))为1.24±0.38μg/L,与实测C_(ss)1.2±0.4μg/L比较,差异无显著性(P>0.05)。  相似文献   
67.
Injection of ozonized normal saline to animals with transplanted sarcoma-45 normalized energy metabolism in the liver, which is important for this organ's function under conditions of malignant growth. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 8, pp. 207–209, August, 1998  相似文献   
68.
A comparative study of the parameters of free-radical lipid peroxidation and antioxidant system was performed in children living in the North for various time periods. Intense lipid peroxidation was shown to be the key factor in the pathogeneses of several diseases caused by disturbances in the cellular membrane. Decreased resistance of red blood cells to peroxidative hemolysis is a phenomenon characterizing the adaptation-violating processes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 9, pp. 342–344, September, 1998  相似文献   
69.
本实验研究了连续服用茶多酚20天,对14月龄小鼠血及肝中SOD、GSH-Px和LPO的影响。结果表明茶多酚能提高血及肝中SOD及GSH-Px活性,与正常对照组比较P<0.01,同时能降低血及肝中LPO含量,与正常对照组比较P<0.01。提示茶多酚可通过降低机体自由基水平,起到抗衰老作用。  相似文献   
70.
用小鼠胎肝细胞体外血浆凝块培养红系集落(Erythroid colong formig unit inculturc,E-CFUc)方法,以红细胞生成素(Erythropoietin,EPO)850323为标准试剂,测定正常人、贫血病人血清EPO浓度。实验用妊娠13~15d小鼠胎肝细胞。血清均经透析处理,培养液中加量最大不超过10%。EPO(850323)在培养液中浓度为2.5~100mU/ml。血清EPO(mU/ml)测定结果:28例正常人为48.O±17.7,12例再生障碍性贫血病人为946~>10000,1例巨幼细胞性贫血病人为500,1例缺铁性贫血病人为400和18例慢性肾功能衰竭病人则为94.2±87.6。结果表明:贫血病因对血清EPO浓度有影响。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号