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   21846篇
  免费   1303篇
  国内免费   547篇
耳鼻咽喉   85篇
儿科学   318篇
妇产科学   283篇
基础医学   5516篇
口腔科学   426篇
临床医学   1273篇
内科学   2763篇
皮肤病学   521篇
神经病学   984篇
特种医学   277篇
外国民族医学   6篇
外科学   1538篇
综合类   3279篇
预防医学   915篇
眼科学   196篇
药学   2631篇
  6篇
中国医学   1366篇
肿瘤学   1313篇
  2024年   46篇
  2023年   278篇
  2022年   400篇
  2021年   674篇
  2020年   722篇
  2019年   642篇
  2018年   572篇
  2017年   687篇
  2016年   644篇
  2015年   708篇
  2014年   1279篇
  2013年   1565篇
  2012年   1281篇
  2011年   1530篇
  2010年   1294篇
  2009年   1309篇
  2008年   1180篇
  2007年   1111篇
  2006年   1034篇
  2005年   800篇
  2004年   751篇
  2003年   658篇
  2002年   517篇
  2001年   384篇
  2000年   401篇
  1999年   364篇
  1998年   371篇
  1997年   290篇
  1996年   309篇
  1995年   275篇
  1994年   266篇
  1993年   193篇
  1992年   176篇
  1991年   122篇
  1990年   79篇
  1989年   65篇
  1988年   56篇
  1987年   38篇
  1986年   48篇
  1985年   124篇
  1984年   109篇
  1983年   58篇
  1982年   68篇
  1981年   46篇
  1980年   38篇
  1979年   29篇
  1978年   21篇
  1977年   20篇
  1976年   21篇
  1975年   19篇
排序方式: 共有10000条查询结果,搜索用时 593 毫秒
1.
The present letter to the editor is in response to the research “Outcomes of curative liver resection for hepatocellular carcinoma in patients with cirrhosis” by Elshaarawy et al in World J Gastroenterol 2021; 13(5): 424–439. The preoperative assessment of the liver reserve function in hepatocellular carcinoma (HCC) patients with cirrhosis is crucial, and there is no universal consensus on how to assess it. Based on a retrospective study, Elshaarawy et al investigated the impact of various classical clinical indicators on liver failure and the prognosis after hepatectomy in HCC patients with cirrhosis. We recommend that we should strive to explore new appraisal indicators, such as the indocyanine green retention rate at 15 min.  相似文献   
2.
《Cancer cell》2022,40(2):153-167.e11
  1. Download : Download high-res image (229KB)
  2. Download : Download full-size image
  相似文献   
3.
Major depressive disorder and other neuropsychiatric disorders are often managed with long-term use of antidepressant medication. Fluoxetine, an SSRI antidepressant, is widely used as a first-line treatment for neuropsychiatric disorders. However, fluoxetine has also been shown to increase the risk of metabolic diseases such as non-alcoholic fatty liver disease. Fluoxetine has been shown to increase hepatic lipid accumulation in vivo and in vitro. In addition, fluoxetine has been shown to alter the production of prostaglandins which have also been implicated in the development of non-alcoholic fatty liver disease. The goal of this study was to assess the effect of fluoxetine exposure on the prostaglandin biosynthetic pathway and lipid accumulation in a hepatic cell line (H4-II-E-C3 cells). Fluoxetine treatment increased mRNA expression of prostaglandin biosynthetic enzymes (Ptgs1, Ptgs2, and Ptgds), PPAR gamma (Pparg), and PPAR gamma downstream targets involved in fatty acid uptake (Cd36, Fatp2, and Fatp5) as well as production of 15-deoxy-Δ12,14PGJ2 a PPAR gamma ligand. The effects of fluoxetine to induce lipid accumulation were attenuated with a PTGS1 specific inhibitor (SC-560), whereas inhibition of PTGS2 had no effect. Moreover, SC-560 attenuated 15-deoxy-Δ12,14PGJ2 production and expression of PPAR gamma downstream target genes. Taken together these results suggest that fluoxetine-induced lipid abnormalities appear to be mediated via PTGS1 and its downstream product 15d-PGJ2 and suggest a novel therapeutic target to prevent some of the adverse effects of fluoxetine treatment.  相似文献   
4.
??Objective    To discuss the influence of basic periodontal therapy on the level of IL-8?? IL-10 in serum and gingival crevicular fluid in patients who have chronic periodontitis complicated by coronary heart disease. Methods     A total of 65 cases of patients with chronic periodontitis complicated by coronary heart disease were selected and divided into two groups randomly??Group A of 35 patients who received the basic periodontal therapy and cardiac medical treatment??Group B of 30 patients who received cardiological treatment only. Then??select 25 patient who had developed chronic severe periodontitis with non-systematic disease to establish group C and give them the basic periodontal therapy only. Observe the changes of the IL-8??IL-10 levels in serum and gingival crevicular fluid and the periodontal infection indexes??BI??PD??. Results    The results showed that after three months of basic periodontal therapy the periodontal clinical indices of both group A and group C became better and the IL-8 level obviously reduced??while the IL-10 level obviously increased. There was no obvious difference between group A and group B in each examination index before the therapy. After three months??we found that the periodontal infection index??SBI PD??of group A was obviously better than group B. Compared to group B??the IL-8 level of group A obviously reduced??and the IL-10 level obviously increased. The difference was statistically significant??P < 0.05??. Conclusion    The basic periodontal therapy can effectively improve periodontal conditions of the patients with chronic periodontal diseases??and reduce the risk of breaking the normal cardiovascular function.  相似文献   
5.
Gut bacteria and gut barrier plays important roles in body homeostasis. Ciprofloxacin (CPFX) is widely used to treat bacterial infections. However, whether high dosage of CPFX has side effects on gut barrier integrity is still unclear. Our results indicated that the High CPFX treatment (1 mg/ml) caused weight loss, nervousness, anorexia, and increased apoptosis cells in gut, but less influence was observed in the Low CPFX group (0.2 mg/ml). Meanwhile, the High CPFX treatment impaired tight junction molecules Ocln/ZO-1 level and down-regulated antibacterial genes expression (reg3γ, pla2g2α and defb1). Further, the High CPFX treatment increased pro-inflammatory cytokine IL-1β in intestinal tract, decreased IL-17A of duodenum but increased IL-17A of colon at day 37. In addition, the gut bacterial diversity and richness behaved significantly loss regarding CPFX treatment, especially in the High CPFX group during the experiment. Indole exhibited sharply decline in both Low and High CPFX groups at day 7, and the High CPFX mice needed longer time on restoring indole level. Meanwhile, CPFX treatment strongly decreased the concentrations of butyric acid and valeric acid at day 1. Correlation analysis indicated that the linked patterns between the key bacteria (families Bacteroidales_S247, Ruminococcaceae and Desulfovibrionaceae) and metabolites (indole and butyric acid) were disturbed via the CPFX treatment. In conclusion, the High CPFX treatment impaired the gut barrier with the evidence of reduced expression of tight junction proteins, increased apoptosis cells and inflammatory cells, decreased the bacterial diversity and composition, which suggesting a proper antibiotic-dosage use should be carefully considered in disease treatment.  相似文献   
6.
ABSTRACT

Purpose

To investigate the expression of IL-11 and its receptor IL-11Rα and to quantify density of CD163+ M2 macrophages in proliferative diabetic retinopathy (PDR).  相似文献   
7.
炎症已成为影响肿瘤细胞增殖转移的第七大因素,而白细胞介素-1(IL-1)是炎性微环境的重要因子之一。中医药在治疗肿瘤时具有多途径、多靶点的优势,同时炎性微环境致病特点与现代中医学"癌毒"的理论相吻合。查阅近年中医药调控IL-1家族分子治疗肿瘤机制的文献,对其进行梳理,并做出概括及评价,从中医药主要调控IL-1α、IL-1β和IL-18因子治疗肿瘤展开综述,为中医药更系统化治疗肿瘤提供参考。  相似文献   
8.
6-Mercaptopurine (6-MP) is commonly used for treatment of acute lymphoblastic leukemia (ALL). The incidence of hematotoxicity caused by this drug is quite high in Asians even using a standard low dosage regimen. The present study was aimed to elucidate the impact of thiopurine S-methyltransferase (TPMT), a nucleoside diphosphate-linked moiety X-type motif 15 (NUDT15), inosine triphosphatase (ITPA) and ATP Binding Cassette Subfamily C Member 4 (ABCC4) polymorphisms on hematotoxicity in pediatric patients who received a standard low starting dose of 6-MP. One hundred and sixty-nine pediatric patients were enrolled and their genotypes were determined. Patients who carried NUDT1513 and NUDT1512 genotypes were at a 10–15 fold higher risk of severe neutropenia than those of the wild-type during the early months of the maintenance phase. Risk of neutropenia was not significantly increased in patients with other NUDT15 variants as well as in patients with TPMT, ITPA or ABCC4 variants. These results suggest that NUDT15 polymorphisms particularly, NUDT1513 and NUDT1512, play major roles in 6-MP-induced severe hematotoxicity even when using a standard low dosage of 6-MP and genotyping of these variants is necessary in order to obtain precise tolerance doses and avoid severe hematotoxicity in pediatric patients.  相似文献   
9.
目的探讨他克莫司联合308nm准分子激光在面部白癜风治疗中的应用效果。方法选取2017年2月-2019年2月医院84例面部白癜风患者为研究对象,根据入院单双号将受试者进行分组,其中对照组42例患者接受308nm准分子激光治疗,研究组42例患者在对照组的基础上联合他克莫司软膏治疗,比较两组患者治疗后1个月、3个月时的治疗总有效率以及治疗前后白斑面积与皮损区IL-17水平变化。结果研究组患者在治疗后1个月、3个月时的治疗总有效率均显著高于对照组(P<0.05),与治疗前相比,治疗后两组患者白斑面积及皮损区IL-17水平均显著减少,且研究组显著少于对照组(P<0.05)。结论他克莫司联合308nm准分子激光可有效缩小白斑面积,降低皮损区IL-17水平,疗效确切。  相似文献   
10.
《药学学报(英文版)》2020,10(9):1634-1645
Systematic administration of anti-inflammatory cytokine interleukin 4 (IL-4) has been shown to improve recovery after cerebral ischemic stroke. However, whether IL-4 affects neuronal excitability and how IL-4 improves ischemic injury remain largely unknown. Here we report the neuroprotective role of endogenous IL-4 in focal cerebral ischemia–reperfusion (I/R) injury. In multi-electrode array (MEA) recordings, IL-4 reduces spontaneous firings and network activities of mouse primary cortical neurons. IL-4 mRNA and protein expressions are upregulated after I/R injury. Genetic deletion of Il-4 gene aggravates I/R injury in vivo and exacerbates oxygen-glucose deprivation (OGD) injury in cortical neurons. Conversely, supplemental IL-4 protects Il-4−/− cortical neurons against OGD injury. Mechanistically, cortical pyramidal and stellate neurons common for ischemic penumbra after I/R injury exhibit intrinsic hyperexcitability and enhanced excitatory synaptic transmissions in Il-4−/− mice. Furthermore, upregulation of Nav1.1 channel, and downregulations of KCa3.1 channel and α6 subunit of GABAA receptors are detected in the cortical tissues and primary cortical neurons from Il-4−/− mice. Taken together, our findings demonstrate that IL-4 deficiency results in neural hyperexcitability and aggravates I/R injury, thus activation of IL-4 signaling may protect the brain against the development of permanent damage and help recover from ischemic injury after stroke.  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