全文获取类型
收费全文 | 153232篇 |
免费 | 14132篇 |
国内免费 | 7465篇 |
专业分类
耳鼻咽喉 | 1416篇 |
儿科学 | 2707篇 |
妇产科学 | 2827篇 |
基础医学 | 38570篇 |
口腔科学 | 4182篇 |
临床医学 | 11458篇 |
内科学 | 20756篇 |
皮肤病学 | 2760篇 |
神经病学 | 11137篇 |
特种医学 | 3140篇 |
外国民族医学 | 28篇 |
外科学 | 12130篇 |
综合类 | 21525篇 |
现状与发展 | 32篇 |
一般理论 | 2篇 |
预防医学 | 7091篇 |
眼科学 | 3704篇 |
药学 | 14838篇 |
29篇 | |
中国医学 | 4094篇 |
肿瘤学 | 12403篇 |
出版年
2024年 | 208篇 |
2023年 | 1756篇 |
2022年 | 3181篇 |
2021年 | 4480篇 |
2020年 | 4448篇 |
2019年 | 4177篇 |
2018年 | 4324篇 |
2017年 | 4882篇 |
2016年 | 5422篇 |
2015年 | 6132篇 |
2014年 | 9708篇 |
2013年 | 11557篇 |
2012年 | 9069篇 |
2011年 | 10629篇 |
2010年 | 8607篇 |
2009年 | 8361篇 |
2008年 | 8596篇 |
2007年 | 8517篇 |
2006年 | 7785篇 |
2005年 | 6724篇 |
2004年 | 5693篇 |
2003年 | 4836篇 |
2002年 | 3619篇 |
2001年 | 3173篇 |
2000年 | 2774篇 |
1999年 | 2316篇 |
1998年 | 2195篇 |
1997年 | 2034篇 |
1996年 | 1881篇 |
1995年 | 1882篇 |
1994年 | 1756篇 |
1993年 | 1496篇 |
1992年 | 1297篇 |
1991年 | 1168篇 |
1990年 | 1037篇 |
1989年 | 976篇 |
1988年 | 846篇 |
1987年 | 754篇 |
1986年 | 644篇 |
1985年 | 966篇 |
1984年 | 878篇 |
1983年 | 587篇 |
1982年 | 715篇 |
1981年 | 570篇 |
1980年 | 510篇 |
1979年 | 436篇 |
1978年 | 308篇 |
1977年 | 248篇 |
1976年 | 227篇 |
1975年 | 91篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
51.
目的 探讨γ干扰素诱导蛋白30(IFI 30)、程序性死亡因子配体1(PD-L1)在人脑胶质瘤中的表达及与病人预后的关系。方法 选择2015年5月~2019年5月手术切除的103例人脑胶质瘤组织和瘤旁组织,采用免疫组织化学染色检测IFI 30、PD-L1表达情况。随访24个月,记录无进展生存期和总生存期。结果 胶质瘤组织IFI 30、PD-L1高表达率[分别为70.87%(73/103)、68.93%(71/103)]明显高于瘤旁组织[分别为19.42%(20/103)、21.36%(22/103);P<0.001]。胶质瘤组织IFI 30表达水平与PD-L1表达水平呈明显正相关(r=0.583,P<0.05)。随访24个月,生存75例,死亡28例;多因素logistic回归分析显示,IFI 30高表达、PD-L1高表达是增加病人死亡风险的独立危险因素(P<0.05)。生存曲线分析显示,IFI 30高表达组2年累积生存率(64.52%)和2年累积无进展生存率(65.56%)均明显低于低表达组(分别为82.25%、89.45%;P<0.05)。PD-L1高表达组2年累积生存率(61.78%)和2年累积无进展生存率(60.14%)均明显低于低表达组(分别为88.52%、79.86%;P<0.05)。结论 人脑胶质瘤组织IFI 30、PD-L1呈高表达,与病人不良预后密切相关。 相似文献
52.
53.
54.
To determine the protective effect of aloe-emodin (AE) from high glucose induced toxicity in RIN-5F (pancreatic β-cell) cell and restoration of its function was analyzed. RIN-5F cells have been cultured in high glucose (25 mM glucose) condition, with and without AE treatment. RIN-5F cells cultured in high glucose decreased cell viability and increased ROS levels after 48 hr compared with standard medium (5.5 mM glucose). Glucotoxicity was confirmed by significantly increased ROS production, increased pro-inflammatory (IFN-γ, IL-1β,) & decreased anti-inflammatory (IL-6&IL-10) cytokine levels, increased DNA fragmentation. In addition, we found increased Bax, caspase 3, Fadd, and Fas and significantly reduced Bcl-2 expression after 48 hr. RIN-5F treated with both high glucose and AE (20 μM) decreased ROS generation and prevent RIN-5F cell from glucotoxicity. In addition, AE treated cells cultured in high glucose were transferred to standard medium, normal responsiveness to glucose was restored within 8hr and normal basal insulin release within 24 hr was achieved when compared to high glucose. 相似文献
55.
56.
Sebastian Mondaca Walid K. Chatila David Bates Jaclyn F. Hechtman Andrea Cercek Neil H. Segal Zsofia K. Stadler Anna M. Varghese Ritika Kundra Marinela Capanu Jinru Shia Nikolaus Schultz Leonard Saltz Rona Yaeger 《Clinical colorectal cancer》2019,18(1):e39-e52
Background
Treatment of advanced anal squamous cell cancer (SCC) is usually with the combination of cisplatin and 5-fluorouracil, which is associated with heterogeneous responses across patients and significant toxicity. We examined the safety and efficacy of a modified schedule, FOLFCIS (leucovorin, fluorouracil, and cisplatin), and performed an integrated clinical and genomic analysis of anal SCC.Patients and Methods
We reviewed all patients with advanced anal SCC receiving first-line FOLFCIS chemotherapy – essentially a FOLFOX (leucovorin, fluorouracil, and oxaliplatin) schedule with cisplatin substituted for oxaliplatin – in our institution between 2007 and 2017, and performed deep sequencing to identify genomic markers of response and key genomic drivers.Results
Fifty-three patients with advanced anal SCC (48 metastatic; 5 unresectable, locally advanced) received first-line FOLFCIS during this period; all were platinum-naive. The response rate was 48% (95% confidence interval [CI], 32.6%-63%). With a median follow-up of 41.6 months, progression-free survival and overall survival were 7.1 months (95% CI, 4.4-8.6 months) and 22.1 months (95% CI, 16.9-28.1 months), respectively. Among all patients with advanced anal SCC that underwent sequencing during the study period, the most frequent genomic alterations consisted of chromosome 3q amplification (51%) and mutations in PIK3CA (29%) and KMT2D (22%). No genomic alteration correlated with response to platinum-containing treatment. Although there were few cases, patients with human papillomavirus-negative anal SCC did not appear to benefit from FOLFCIS, and all harbored distinct genomic profiles with TP53, TERT promoter, and CDKN2A mutations.Conclusions
FOLFCIS appears effective and safe as first-line chemotherapy in patients with advanced anal SCC and represents an alternative treatment option for these patients. 相似文献57.
Understanding the contribution of endothelial cells to the progenitor pools of adult tissues has the potential to inform therapies for human disease.To address whether endothelial cells transdifferentiate into non-vascular cell types,we performed cell lineage tracing analysis using transgenic mice engineered to express a fluorescent marker following activation by tamoxifen in vascular endothelial cadherin promoter-expressing cells(VEcad-CreERT2;B6 Cg-Gt(ROSA)26Sortm9(CAG-tdTomato)Hze).Activation of target-cell labeling following 1.5 months of ad libitum feeding with tamoxifen-laden chow in 4–5 month-old mice resulted in the tracing of central nervous system and peripheral cells that include:cerebellar granule neurons,ependymal cells,skeletal myocytes,pancreatic beta cells,pancreatic acinar cells,tubular cells in the renal cortex,duodenal crypt cells,ileal crypt cells,and hair follicle stem cells.As Nestin expression has been reported in a subset of endothelial cells,Nes-CreERT2 mice were also utilized in these conditions.The tracing of cells in adult Nes-CreERT2 mice revealed the labeling of canonical progeny cell types such as hippocampal and olfactory granule neurons as well as ependymal cells.Interestingly,Nestin tracing also labeled skeletal myocytes,ileal crypt cells,and sparsely marked cerebellar granule neurons.Our findings provide support for endothelial cells as active contributors to adult tissue progenitor pools.This information could be of particular significance for the intravenous delivery of therapeutics to downstream endothelial-derived cellular targets.The animal experiments were approved by the Boise State University Institute Animal Care and Use Committee(approval No.006-AC15-018)on October 31,2018. 相似文献
58.
目的比较双球囊与缩宫素用于促宫颈成熟并引产的临床效果。方法选取于2017年7月—2018年7月在本院分娩的足月妊娠孕妇100例为研究对象,随机平均分为观察组和对照组各50例,观察组采用双球囊引产,对照组采用缩宫素进行引产,对比2组孕妇的总产程、宫颈成熟度、引产成功率和新生儿Apgar评分、并发症发生率等。结果观察组促宫颈成熟有效率(100%)、引产成功率(96%)均高于对照组(82%,74%),差异均有统计学意义(P<0.05),治疗后新生儿Apgar评分、并发症发生率差异均无统计学意义(P>0.05);宫颈Bishop评分观察组(9.12±1.42)高于对照组(7.92±1.56),观察组总产程(8.23±2.54)h,对照组(13.45±3.77)h,差异均有统计学意义(P<0.05)。结论双球囊用于妊娠引产效果显著,能明显促进宫颈成熟、缩短产程,保障分娩的顺利进行,安全可靠,值得在临床中推广。 相似文献
59.
60.