全文获取类型
收费全文 | 71668篇 |
免费 | 6067篇 |
国内免费 | 2721篇 |
专业分类
耳鼻咽喉 | 1303篇 |
儿科学 | 1655篇 |
妇产科学 | 1229篇 |
基础医学 | 8230篇 |
口腔科学 | 2395篇 |
临床医学 | 6474篇 |
内科学 | 6415篇 |
皮肤病学 | 1002篇 |
神经病学 | 2646篇 |
特种医学 | 3865篇 |
外国民族医学 | 54篇 |
外科学 | 8758篇 |
综合类 | 11791篇 |
现状与发展 | 20篇 |
预防医学 | 1827篇 |
眼科学 | 1231篇 |
药学 | 4805篇 |
49篇 | |
中国医学 | 2135篇 |
肿瘤学 | 14572篇 |
出版年
2024年 | 131篇 |
2023年 | 975篇 |
2022年 | 1706篇 |
2021年 | 2968篇 |
2020年 | 2402篇 |
2019年 | 2182篇 |
2018年 | 2071篇 |
2017年 | 2311篇 |
2016年 | 2562篇 |
2015年 | 2767篇 |
2014年 | 4281篇 |
2013年 | 4334篇 |
2012年 | 3927篇 |
2011年 | 4300篇 |
2010年 | 3591篇 |
2009年 | 3583篇 |
2008年 | 3599篇 |
2007年 | 3833篇 |
2006年 | 3476篇 |
2005年 | 3089篇 |
2004年 | 2692篇 |
2003年 | 2300篇 |
2002年 | 2096篇 |
2001年 | 1906篇 |
2000年 | 1575篇 |
1999年 | 1471篇 |
1998年 | 1262篇 |
1997年 | 1191篇 |
1996年 | 1055篇 |
1995年 | 928篇 |
1994年 | 792篇 |
1993年 | 657篇 |
1992年 | 547篇 |
1991年 | 482篇 |
1990年 | 379篇 |
1989年 | 386篇 |
1988年 | 349篇 |
1987年 | 290篇 |
1986年 | 248篇 |
1985年 | 294篇 |
1984年 | 282篇 |
1983年 | 155篇 |
1982年 | 217篇 |
1981年 | 196篇 |
1980年 | 151篇 |
1979年 | 127篇 |
1978年 | 101篇 |
1977年 | 71篇 |
1976年 | 65篇 |
1975年 | 36篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
《药学学报(英文版)》2020,10(7):1294-1308
A great challenge in multi-targeting drug discovery is to identify drug-like lead compounds with therapeutic advantages over single target inhibitors and drug combinations. Inspired by our previous efforts in designing antitumor evodiamine derivatives, herein selective histone deacetylase 1 (HDAC1) and topoisomerase 2 (TOP2) dual inhibitors were successfully identified, which showed potent in vitro and in vivo antitumor potency. Particularly, compound 30a was orally active and possessed excellent in vivo antitumor activity in the HCT116 xenograft model (TGI = 75.2%, 150 mg/kg, p.o.) without significant toxicity, which was more potent than HDAC inhibitor vorinostat, TOP inhibitor evodiamine and their combination. Taken together, this study highlights the therapeutic advantages of evodiamine-based HDAC1/TOP2 dual inhibitors and provides valuable leads for the development of novel multi-targeting antitumor agents. 相似文献
43.
Taisuke Inada Satoshi Fukushima Masayuki Murai Masatoshi Jinnin Azusa Miyashita Satoshi Nakahara Junji Yamashita Jun Aoi Shinichi Masuguchi Hironobu Ihn 《The Journal of dermatology》2015,42(2):198-201
miRNA‐221 (miR‐221) is known to be abnormally expressed in many human cancers. The serum levels of miR‐221 have been reported as a tumor marker for malignant melanoma (MM). We hypothesized that the hair shaft miR‐221 levels may be increased in patients with MM. We therefore assessed the possibility that hair shaft miR‐221 levels could be a marker for MM. The hair shaft miR‐221 levels were significantly higher in patients with MM than controls. The rates of increased hair shaft miR‐221 levels above the cut‐off value were comparable to those of serum 5‐S‐CD, which is a tumor marker commonly used for MM. Measurements of the hair shaft miR‐221 levels could have potential clinical value in the detection of MM. This is the first report investigating the hair shaft levels of an miRNA in patients with MM. Our investigations offer new insight into the relationship between miR‐221 and MM, and may provide a new, non‐invasive way to screen for melanoma. 相似文献
44.
45.
46.
Roberto V.P. Ribeiro Mitesh V. Badiwala Danny Ramzy Laura C. Tumiati Vivek Rao 《The Journal of thoracic and cardiovascular surgery》2019,157(2):615-625.e1
Objective
Hypertonic saline (HTS) has potent immune and vascular effects. We assessed recipient pretreatment with HTS on allograft function in a porcine model of heart transplantation and hypothesized that HTS infusion would limit endothelial and left ventricular (LV) dysfunction following transplantation.Methods
Heart transplants were performed after 6 hours of cold ischemic storage. Recipient pigs were randomized to treatment with or without HTS (7.5% NaCl) before cardiopulmonary bypass (CPB). Using a myograft apparatus, coronary artery endothelial-dependent (Edep) and -independent (Eind) relaxation was assessed. LV performance was determined using pressure-volume loop analysis. Pulmonary interleukin (IL)-2, IL-6, and tumor necrosis factor (TNF)-α expression was measured.Results
Weaning from CPB and LV performance after transplantation were improved in HTS-treated animals. Successful weaning from CPB was greater in the HTS-treated hearts (8 of 8 vs 2 of 8; P < .05). Mean LV functional recovery was improved in the HTS-treated animals, as assessed by preload recruitable stroke work (65 ± 10% vs 27 ± 10%; P < .001) and end-systolic elastance (55 ± 7% vs 37 ± 4%; P < .001). Treatment with HTS resulted in improved Edep (mean maximum elastance [Emax], 56 ± 5% vs 37 ± 7%; P < .001) and Eind (mean Emax%, 77 ± 6% vs 52 ± 4%; P < .001) vasorelaxation compared with control. Pulmonary expression of IL-2, IL-6, and TNF-α increased following transplantation, whereas HTS therapy attenuated IL production (P < .001). Transplantation increased plasma TNF-α levels and LV TNF-α expression, whereas HTS prevented this up-regulation (P < .001).Conclusions
Recipient HTS pretreatment preserves allograft vasomotor and LV function, and HTS therapy limits CPB-induced injury. HTS may be a novel recipient intervention to prevent graft dysfunction. 相似文献47.
48.
�� ��a������ٻb��������a��������a������������ �� 《中国实用外科杂志》2019,39(2):194-196
49.
L.F. Mejía J.C. Gil M. Jaramillo 《Archivos de la Sociedad Espa?ola de Oftalmología》2019,94(7):331-336
ObjectiveTo propose the Intense Pulsed Light (IPL) therapy as a helpful supplementary treatment in patients with dry eye disease.Material and methodsRetrospective cross sectional design. Medical records of patients in whom dry eye disease symptoms were not satisfactorily controlled with medical therapy alone and who underwent additional IPL with at least three sessions completed. Data were analyzed before therapy and 3 weeks after its completion to asses improvement. Determination of symptoms, through a visual analog scale; tear film stability, through tear Break Up Time (tBUT); measurement of tear secretion, through Schirmer Test; and ocular surface staining with Van Bijsterveld score were evaluated. SPSS software and nonparametric analysis of repeated measures were used. The study was approved by the ethics committee.Results50 eyes from 25 subjects were reviewed. There were 9 males (36%) and 16 females (64%), with a median age of 59 years (IQR 52-64). The median of the symptoms scale was 8 (IQR 8-9) and 3 (IQR 2-4) before and after the therapy respectively (P < .05). The median of BUT was 4 (IQR 3-5) and 10 (IQR 8-11), Schirmer test was 13 (IQR 12-15) and 15 (IQR 13-20), and Van Bijsterveld score was 3 (RIC 3-4) and 2 (IQR 2-3) before and after the therapy respectively (P < .05, for all measurements).ConclusionIPL treatment has excellent results regarding both: dry eye disease symptoms improvement and in office objective tests such as tBUT, Schirmer test and Van Bijsterveld score; IPL could be considered as an effective adjunct for dry eye disease. 相似文献
50.
ObjectiveProgrammed death ligand 1 (PD-L1) has been reported to be connected to prognosis in individuals with malignant pleural mesothelioma (MPM), although there is no consensus based on data from previous studies. Accordingly, this quantitative meta-analysis investigated prognostic and clinicopathological utility of PD-L1 in patients with MPM.MethodsA comprehensive search of the PubMed, Web of Science, Embase, and Cochrane Library databases for articles published up to October 4, 2019 was performed. Studies using immunohistochemical techniques to detect/quantify the expression of PD-L1 in MPM tissue were enrolled in the analysis. The combined hazard ratio (HR) and corresponding 95% confidence interval (CI) was applied to assess the association between PD-L1 expression and overall survival (OS).ResultsA total of 11 studies comprising 1606 patients was included in the present meta-analysis. For OS, pooled data revealed an HR of 1.50 (95% CI 1.32–1.70; p < 0.001), suggesting that patients with PD-L1 overexpression experience inferior OS. Subgroup analysis revealed that elevated PD-L1 remained a significant prognostic indicator for worse OS, irrespective of sample size, cut-off value, ethnicity, and Newcastle-Ottawa Scale score. Moreover, PD-L1 overexpression was associated with non-epithelioid histology (odds ratio 4.30 [95% CI 1.89–9.74]; p < 0.001).ConclusionsResults of this meta-analysis show that elevated expression of PD-L1 could be a factor predicting poorer survival in patients with MPM. 相似文献