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   74424篇
  免费   7131篇
  国内免费   5016篇
耳鼻咽喉   569篇
儿科学   967篇
妇产科学   604篇
基础医学   7332篇
口腔科学   1741篇
临床医学   9324篇
内科学   9204篇
皮肤病学   874篇
神经病学   3455篇
特种医学   3476篇
外国民族医学   40篇
外科学   8462篇
综合类   15288篇
现状与发展   18篇
一般理论   13篇
预防医学   5696篇
眼科学   1716篇
药学   7763篇
  86篇
中国医学   4960篇
肿瘤学   4983篇
  2024年   250篇
  2023年   949篇
  2022年   2581篇
  2021年   3540篇
  2020年   2858篇
  2019年   2185篇
  2018年   2368篇
  2017年   2252篇
  2016年   2003篇
  2015年   3277篇
  2014年   4434篇
  2013年   4430篇
  2012年   6358篇
  2011年   6789篇
  2010年   5163篇
  2009年   4571篇
  2008年   4828篇
  2007年   4470篇
  2006年   4477篇
  2005年   3805篇
  2004年   2586篇
  2003年   2299篇
  2002年   1859篇
  2001年   1322篇
  2000年   1310篇
  1999年   1095篇
  1998年   667篇
  1997年   657篇
  1996年   449篇
  1995年   406篇
  1994年   364篇
  1993年   210篇
  1992年   269篇
  1991年   204篇
  1990年   169篇
  1989年   133篇
  1988年   138篇
  1987年   117篇
  1986年   112篇
  1985年   81篇
  1984年   39篇
  1983年   31篇
  1982年   24篇
  1979年   38篇
  1974年   36篇
  1973年   31篇
  1969年   32篇
  1968年   23篇
  1967年   30篇
  1966年   31篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
Zedoary tumeric (Curcumae Rhizoma, Ezhu in Chinese) has a long history of application and has great potential in the treatment of liver cancer. The anti liver cancer effect of zedoary tumeric depends on the combined action of multiple pharmacodynamic substances. In order to clarify the specific mechanism of zedoary tumeric against liver cancer, this paper first analyzes the mechanism of its single pharmacodynamic substance against liver cancer, and then verifies the joint anti liver cancer mechanism of its "pharmacodynamic group". By searching the research on the anti hepatoma effect of active components of zedoary tumeric in recent years, we found that pharmacodynamic substances, including curcumol, zedoarondiol, curcumenol, curzerenone, curdione, curcumin, germacrone, β-elemene, can act on multi-target and multi-channel to play an anti hepatoma role. For example, curcumin can regulate miR, GLO1, CD133, VEGF, YAP, LIN28B, GPR81, HCAR-1, P53 and PI3K/Akt/mTOR, HSP70/TLR4 and NF-κB. Wnt/TGF/EMT, Nrf2/Keap1, JAK/STAT and other pathways play an anti hepatoma role. Network pharmacological analysis showed that the core targets of the "pharmacodynamic group" for anti-life cancer are AKT1, EGFR, MAPK8, etc, and the core pathways are neuroactive live receiver interaction, nitrogen metabolism, HIF-1 signaling pathway, etc. At the same time, by comparing and analyzing the relationship between the specific mechanisms of pharmacodynamic substance and "pharmacodynamic group", it is found that they have great reference significance in target, pathway, biological function, determination of core pharmacodynamic components, formation of core target protein interaction, in-depth research of single pharmacodynamic substance, increasing curative effect and so on. By analyzing the internal mechanism of zedoary tumeric pharmacodynamic substance and "pharmacodynamic group" in the treatment of liver cancer, this paper intends to provide some ideas and references for the deeper pharmacological research of zedoary tumeric and the relationship between pharmacodynamic substance and "pharmacodynamic group".  相似文献   
2.
BackgroundComminuted patellar fractures are not rare, and the ideal treatment method remains controversial. The present study was conducted to evaluate effects and compare complications of two different methods used to treat comminuted patellar fractures.MethodsFrom March 2010 to August 2016, 102 cases of 34-C2 or 34-C3 comminuted patellar fractures were treated at our hospital, wherein patients received two different treatments: titanium cable tension band with cerclage method (group A) and intrafragmentary screws with X-shaped plating technique (group B). At follow-ups, articular step-off, range of motion (ROM), Lysholm scores, time of union, and complications were recorded and analyzed. Radiographic and clinical data as well as rate of complications were statistically analyzed.ResultsIn total, 87 patients were included in the final analysis (n = 47 in group A and n = 40 in group B). No significant differences were noted in terms of cost of implant, age, gender, rate of 34-C3 fractures, rate of layered inferior pole fractures, postoperative articular step-off and union time. At 2-year follow-up, average Lysholm scores, ROM and rate of complications were (89.0 ± 4.5), (122°±12°) and (27.7%) in group A and (90.2 ± 3.9), (124°±11°) and (17.5%) in group B, respectively, with no significant differences (p > 0.05). The mean time of surgery in group B was shorter than that in group A with significant difference (p < 0.05).ConclusionsTreatment using the intrafragmentary screws and plate method for amenable comminuted patellar fractures achieved similar complication rate and favorable functional outcomes at the 2-year follow-up, which was comparable to the titanium cable tension band with cerclage method. Thus, the intrafragmentary screws and plate method is effective, safe and convenient for 34-C2/C3 comminuted patellar fractures, especially appropriate for patients with layered fragments.  相似文献   
3.
Recent epidemiological studies suggested that proton pump inhibitor (PPI) use was associated with an increased risk of biliary tract cancer (BTC), however, confounders were not adequately controlled. Our study aimed to evaluate PPI use and subsequent risk of BTC and its subtypes in three well-established cohorts. We conducted a pooled analysis of the subjects free of cancers in UK Biobank (n = 463 643), Nurses' Health Study (NHS, n = 80 235) and NHS II (n = 95 869). Propensity score weighted Cox models were used to estimate marginal HRs of PPIs use on BTC risk, accounting for potential confounders. We documented 284 BTC cases in UK Biobank (median follow-up: 7.6 years), and 91 cases in NHS and NHS II cohorts (median follow-up: 15.8 years). In UK biobank, PPI users had a 96% higher risk of BTC compared to nonusers in crude model (HR 1.96, 95% CI 1.44-2.66), but the effect was attenuated to null after adjusting for potential confounders (HR 0.95, 95% CI 0.60-1.49). PPI use was not associated with risk of BTC in the pooled analysis of three cohorts (HR 0.93, 95% CI 0.60-1.43). We also observed no associations between PPI use with risk of intrahepatic (HR 1.00, 95% CI 0.49-2.04), extrahepatic bile duct (HR 1.09, 95% CI 0.52-2.27) and gallbladder cancers (HR 0.66, 95% CI 0.26-1.66) in UK Biobank. In summary, regular use of PPIs was not associated with the risk of BTC and its subtypes.  相似文献   
4.
The research and development of penicillin started with difficulty before 1949 and achieved certain results. In 1951, after the founding of the People's Republic of China, Zhang Weishen, as the only Chinese scientist who had been trained and worked in a penicillin research and development center in the United States for many years, overcame many difficulties and returned to China. In 1953, with the efforts of Zhang Weishen and his colleagues, China realized the industrialized production of penicillin, alleviating the urgent needs of the masses. Antibiotics has also become the first discipline to achieve major scientific and technological achievements after the founding of the New China. In the mid-1950s, the technical breakthrough in the localization of lactose substitutes marked the localization of the raw materials of the penicillin-producing culture medium, which paved the way for the industrialized production of penicillin with Chinese characteristics. Antibiotics have become one of the most widely used and affordable drugs for hundreds of millions of patients in China, and China has since ended the humiliating history of the “Sick Man of East Asia".  相似文献   
5.
目的研究腹腔镜经脐单一部位幽门环肌切开术治疗小儿先天性肥厚性幽门狭窄的临床效果。方法100例小儿先天性肥厚性幽门狭窄患儿作为研究对象,按照随机方式分为观察组和对照组,每组50例。对照组采用腹腔镜幽门环肌切开术治疗,观察组采用腹腔镜经脐单一部位幽门环肌切开术治疗。观察记录患儿的手术结果及随访结果,并比较两组患儿手术时间、术后住院时间。结果手术过程顺利,100例患儿均成功完成手术,无一例中转开腹手术,无并发症发生。观察组患儿术后6 h将胃管取下,少量喂入温水后逐渐过渡到喂糖水、喂奶;对照组患儿术后24 h开始逐渐进食。患儿术后进行6个月的延续性随访,观察组患儿切口恢复美观,已经无法观察到切口瘢痕,两组患儿的生长发育均显示正常状态。观察组患儿手术时间(21.23±1.65)min及术后住院时间(5.58±1.98)d均显著短于对照组的(38.44±1.23)min、(9.67±1.22)d,差异具有统计学意义(P<0.05)。结论先天性肥厚性幽门狭窄患儿采用腹腔镜经脐单一部位幽门环肌切开术治疗,手术效果良好,手术创伤小而且安全。  相似文献   
6.
目的:通过对颈椎病患者上下终板弧形高度、椎间隙高度与椎间隙后骨赘的影像学测量,研究其相关性及其临床应用价值。方法:收集2017年9月至2018年9月颈椎病手术108例患者的临床资料,男48例,年龄30~72岁,平均52岁,女60例,年龄37~79岁,平均54岁。其中C2,3 6例,C3,4 15例,C4,5 32例,C5,6 42例,C6,7 13例。术前及术后摄颈椎X线片,利用PACS(Picture Archiving and Communication Systems)调阅影像,测量椎间隙的下上终板弧形高度(L1,L2),椎间隙高度(L3)及后方骨赘的宽度(L4)。利用Spearman分析它们之间的相关性。结果:L1与L4对比(r=-0.34,P<0.05),L3与L4对比(r=-0.36,P<0.05),存在负相关。L1与L3对比(r=0.38,P<0.05),L2与L3对比(r=0.48,P<0.05),存在正相关。L1与L2对比(P>0.05),L2与L4对比(P>0.05),差异无统计学意义。结论:下终板弧形高度与椎间隙后缘骨赘宽度呈负相关,通过其测量可明确颈椎退变程度,对颈椎病的早期防治有指导意义。  相似文献   
7.
儿童晕厥临床诊治研究的发展与未来   总被引:1,自引:0,他引:1  
儿童晕厥在临床常见,严重影响儿童的身心健康.儿童晕厥诊断关键技术的建立、诊断程序及个体化治疗新策略的提出,显著提高了儿童晕厥的诊治水平.基于研究成果,我国先后制定了多部儿童晕厥诊治指南与专家共识,并在国际期刊颁布了儿童和青少年晕厥指南,充分发挥了中国在国际儿童晕厥诊治领域的引领作用.今后尚需进一步开展儿童晕厥的流行病学研究,优化儿童晕厥预警体系以及干预与预防新策略,进一步推进儿童晕厥事业的发展.  相似文献   
8.
9.
10.
目的 评价中老年人社会资本量表的信效度,探索其在不同健康状况的中老年人群间的区分度。方法 针对已编制的中老年人社会资本量表,采用多阶段分层随机抽样方法,在四川省成都市及泸州市共抽取1 367名50岁及以上中老年居民进行问卷调查。运用Cronbach’s α系数、Pearson相关系数、t检验、探索性因子分析等方法评价量表的信度和效度。结果 1 367名中老年调查对象的社会资本量表总Cronbach’s α系数为0.67,各维度条目与总分的相关系数在0.30~0.79之间,具有良好的信度;探索性因子分析表明,14个条目提取出5个特征根大于1的因子,累积方差贡献率为68.84%;现患慢性疾病的中老年病例组人群的个人社会资本得分、家庭社会资本得分、社团社会资本得分、社区社会资本得分及社会资本总得分均低于未患病的对照人群组,宏观社会资本得分高于对照人群组,且差异均有统计学意义 (均 P<0.01),提示该量表具有较好的区分度。结论 中老年人社会资本量表具有较好的信度和效度,且对不同健康状况的50岁及以上中老年人中有较好的区分度。  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