全文获取类型
收费全文 | 288909篇 |
免费 | 28140篇 |
国内免费 | 19445篇 |
专业分类
耳鼻咽喉 | 2683篇 |
儿科学 | 3946篇 |
妇产科学 | 2694篇 |
基础医学 | 26383篇 |
口腔科学 | 5304篇 |
临床医学 | 37739篇 |
内科学 | 34980篇 |
皮肤病学 | 3419篇 |
神经病学 | 10842篇 |
特种医学 | 10442篇 |
外国民族医学 | 104篇 |
外科学 | 26552篇 |
综合类 | 63050篇 |
现状与发展 | 83篇 |
一般理论 | 17篇 |
预防医学 | 26051篇 |
眼科学 | 7045篇 |
药学 | 31940篇 |
422篇 | |
中国医学 | 22679篇 |
肿瘤学 | 20119篇 |
出版年
2024年 | 1140篇 |
2023年 | 4186篇 |
2022年 | 10727篇 |
2021年 | 13658篇 |
2020年 | 11133篇 |
2019年 | 8302篇 |
2018年 | 8766篇 |
2017年 | 9321篇 |
2016年 | 8328篇 |
2015年 | 13498篇 |
2014年 | 16557篇 |
2013年 | 17209篇 |
2012年 | 25284篇 |
2011年 | 26996篇 |
2010年 | 20693篇 |
2009年 | 17250篇 |
2008年 | 19190篇 |
2007年 | 18466篇 |
2006年 | 16855篇 |
2005年 | 14549篇 |
2004年 | 10033篇 |
2003年 | 9301篇 |
2002年 | 7658篇 |
2001年 | 5897篇 |
2000年 | 4711篇 |
1999年 | 3623篇 |
1998年 | 2086篇 |
1997年 | 2069篇 |
1996年 | 1587篇 |
1995年 | 1398篇 |
1994年 | 1170篇 |
1993年 | 711篇 |
1992年 | 716篇 |
1991年 | 621篇 |
1990年 | 552篇 |
1989年 | 430篇 |
1988年 | 395篇 |
1987年 | 371篇 |
1986年 | 258篇 |
1985年 | 199篇 |
1984年 | 101篇 |
1983年 | 85篇 |
1982年 | 48篇 |
1981年 | 49篇 |
1980年 | 27篇 |
1979年 | 55篇 |
1978年 | 19篇 |
1977年 | 20篇 |
1974年 | 25篇 |
1973年 | 33篇 |
排序方式: 共有10000条查询结果,搜索用时 10 毫秒
61.
缺血性脑血管病患者的血脂水平 总被引:4,自引:0,他引:4
目的分析缺血性脑血管病(ICVD)患者的血脂水平,为今后预防保健及康复干预决策的制定提供依据。方法在佛山市第一人民医院病案数据库中检索1991-2004年诊断为ICVD的病例共2886例,其中2000-2004年ICVD患者共1430例为一亚组,以我院同时期保健科随机选取的400名健康体检人群为对照组,记录血脂情况,进行对照分析。结果血TC、TG和LDL—C水平ICVD患者组明显高于健康体检人群,差异有统计学意义。男女两性血脂水平均随年龄增加而逐渐增高,50岁以上女性血脂水平明显高于同龄组男性。血脂代谢异常患病率随着年代的推移呈逐步上升趋势,总胆固醇从1991—1994年的24.5%到2001-2004年的38.1%(男性)和22.3%到38.5%(女性),且明显高于国内2000-2001年普查人群高脂血症的患病率。结论佛山地区血脂异常是ICVD的重要原因之一。 相似文献
62.
Objective: To study the calcium channel reaction of human Leydig cells induced by hCG/ATP at different extracellular calcium ion concentrations. Methods: The Leydig cell calcium ion concentration was examined with laser confocal microscope, when the cells were stimulated with hCG/ATP at different extracellular calcium contrations. Results: With calcium-containing extracellular fluid, the Leydig cells were sensitive to hCG stimulation and when the extracellular fluid was calcium-free, the Leydig cells did not respond to the stimulation. However, the Leydig cells did respond to ATP stimulation no matter the extracellular fluid contained calcium or not. Conclusion: In human Leydig cells, there are calcium channels sensitive to hCG and ATP. The extracellular calcium ion concentration plays an important role in the regulation of Leydig cell metabolism by hCG/ATP. 相似文献
63.
64.
65.
Objective: To analyze quantitatively the synergistic and antagonistic effects of combined oxymatrine (OMT) and 5-fluorouracil (5-GU)
on a cell line of human liver cancer (HepG2) with median-effect principle in vitro. Methods: The median-effect principle and MTT method were used in the quantitative analysis of effects of the two drugs. Results: Cytotoxic activity of the individual drugs enhanced as drug concentration increased. As fa=0.41, a CI equal to 1 indicated
additivity; fa<0.41, a CI less than 1 indicated synergy; and fa>0.41, a CI greater than 1 indicated antagonism. The sequence
of administration did not influence the cytotoxic activity of the combined antitumor drugs. The ratio of drug concentration
was a factor that can influence the killing effect. Conclusion: The combined drugs interaction (CI<1) was synergistic at lower concentration and antagonistic at higher concentration. The
ratio of drug concentration is a factor that can influence the killing effect.
Biography: HE Song(1965–), male, doctor of medicine, associate professor, Chongqing Medical University, majors in gastroenterology. 相似文献
66.
In this study antigen-independent factor in the pathogenesis of chronic rejection of organ transplants was examined.Kidney isografts and allografts were transplanted orthotopically into bilaterally nephroectomized rat recipients and studied functionaaly,morphologically and immunohistologically,at serial intervals up to 52 weeks after transplantation.Allograft recipients developed progressive proteinuria after 12 weeks,with gradual renal failure ultimately leading to death.At the same time,morphological changes,including progressive arteriosclerosis and glomerulosclerosis ,tubular atrophy and interstitial fibrosis,developed.Immunohistologically,macrophages infiltrated glomeruli during this period and cytokines became unregulated.Our results showed that antigen-independent functional and morphological changes occurred in long-tern kidney isografts and mimicked those appearing much earlier in allografts that reject chronically.Initial injury and extent of functioning renal mass is suggested to be important factor for such late changes. 相似文献
67.
68.
目的探讨护理管理路径在应用佩尔地平治疗的重度子痫前期病人的效果,以期达到最佳的治疗效果,并减少并发症的发生。方法将用佩尔地平针治疗的重度子痫前期的病人486例随机分为两组,一组按常规护理,另一组按制定的护理管理路径护理。结果患者依从性对照组为168例,占70%;观察组为228例,占92.68%,P〈0.05,其差异有统计学意义。胎死宫内发生率对照组为9.16%,观察组为0.81%,P〈0.05,其差异有统计学意义。血压的稳定性对照组为36.3%,观察组为97.6%,P〈0.05,其差异有统计学意义。结论护理管理路径可以提高重度妊娠高血压疾病的治疗效果,减少并发症的发生。 相似文献
69.
Objective: To study the relationship between transaldolase activity, protein expression and testosterone synthesis in Leydig cells of pubertal mice. Methods: Leydig cells were cultured for 2 hours and 8 hours, to the Stimulation Group, hCG was added and to the Controls, only the vehicle. The testosterone concentration was then determined by enzyme-linked immunoadsordent assay (ELISA) and the transaldolase activity and protein expression by Western blot. Results: (1) Both the testosterone concentration and the transaldolase activity in both Stimulation Groups were significantly higher than those in the corresponding Controls (2 h: p<0.05-0.01; 8 h: P<0.001); (2) The ratios of the A isoform, the B isoform and the total transaldolase protein to β-actin between the Stimulation and Control Groups did not differ signifi-cantly. Conclusion: hCG stimulates the transaldolase activity as well as the testosterone synthesis in the Leydig cells of pubertal mice, indicating a positive relationship between them. 相似文献
70.
Kousaku Matsubara M.D. Kei Suzuki M.D. Ying Wei Lin M.D. Toshiyuki Yamamoto M.D. Shigeru Ohta M.D. 《Pediatrics international》1991,33(4):482-487
We present two female siblings with familial juvenile nephronophthisis (FJN) which was diagnosed at the early stage of renal failure. Diagnosis was made during the investigation of anemia in case 1 and by a subsequent family survey in case 2. Most patients with FJN are not identified until the terminal stage of renal failure and such cases have rarely been reported in Japan. Case 2 had a reduction in the maximum urinary concentration ability but no azotemia, and among the FJN patients reported in Japan so far she has the least advanced renal disease. Histological examination of the renal biopsy in case 1 showed typical findings of FJN, such as thickening and lamination of the tubular basement membrane (TBM), interstitial fibrosis, and round cell infiltration of the interstitium. In case 2, renal biopsy revealed an irregular marked thickening of the TBM with trivial interstitial changes and a normal glomerular appearance. The histology of these two cases suggests that the TBM may be the primary site affected in FJN. 相似文献