全文获取类型
收费全文 | 127712篇 |
免费 | 11928篇 |
国内免费 | 5923篇 |
专业分类
耳鼻咽喉 | 1407篇 |
儿科学 | 2068篇 |
妇产科学 | 1976篇 |
基础医学 | 15628篇 |
口腔科学 | 2278篇 |
临床医学 | 14084篇 |
内科学 | 20838篇 |
皮肤病学 | 2307篇 |
神经病学 | 6884篇 |
特种医学 | 5486篇 |
外国民族医学 | 25篇 |
外科学 | 14039篇 |
综合类 | 16740篇 |
现状与发展 | 31篇 |
一般理论 | 41篇 |
预防医学 | 8405篇 |
眼科学 | 4158篇 |
药学 | 12907篇 |
79篇 | |
中国医学 | 5335篇 |
肿瘤学 | 10847篇 |
出版年
2024年 | 88篇 |
2023年 | 1234篇 |
2022年 | 1834篇 |
2021年 | 4413篇 |
2020年 | 3537篇 |
2019年 | 3451篇 |
2018年 | 3907篇 |
2017年 | 3556篇 |
2016年 | 3787篇 |
2015年 | 5360篇 |
2014年 | 6720篇 |
2013年 | 6970篇 |
2012年 | 10039篇 |
2011年 | 10637篇 |
2010年 | 6869篇 |
2009年 | 5963篇 |
2008年 | 7723篇 |
2007年 | 7687篇 |
2006年 | 7369篇 |
2005年 | 6690篇 |
2004年 | 5557篇 |
2003年 | 5627篇 |
2002年 | 4836篇 |
2001年 | 3586篇 |
2000年 | 2932篇 |
1999年 | 2502篇 |
1998年 | 1278篇 |
1997年 | 1135篇 |
1996年 | 939篇 |
1995年 | 862篇 |
1994年 | 809篇 |
1993年 | 601篇 |
1992年 | 894篇 |
1991年 | 841篇 |
1990年 | 762篇 |
1989年 | 695篇 |
1988年 | 562篇 |
1987年 | 588篇 |
1986年 | 494篇 |
1985年 | 394篇 |
1984年 | 274篇 |
1983年 | 198篇 |
1982年 | 138篇 |
1981年 | 119篇 |
1980年 | 123篇 |
1979年 | 167篇 |
1978年 | 99篇 |
1977年 | 80篇 |
1976年 | 82篇 |
1975年 | 85篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
目的 观察具有益气化痰活血作用的冠心康对人单核/巨噬细胞株THP-1细胞PERK-eIF2α信号通路及相关活化转录因子(ATF)和C/EBP同源转录因子(CHOP)的影响,探究冠心康对胆固醇在巨噬细胞内质网中的代谢稳态调节及作为“脂毒”流出后异常沉积的相关作用。方法 采用100 ng·mL-1 PMA及80 μg·mL-1氧化低密度脂蛋白诱导THP-1细胞株,构建巨噬细胞模型,并随机分为模型组、冠心康组、辛伐他汀组、正常组。分别采用10%小牛血清及含药血清干预模型细胞72 h后收集细胞。HE染色观察巨噬细胞病理形态变化,同时进行胆固醇及脂滴含量测定。分别采用Real-time PCR及Western blot法检测各组细胞PERK、eIF2α、ATF、CHOP mRNA及蛋白的表达。结果 HE染色观察到模型组细胞内呈现较多红色脂滴,经胆固醇含量测定,明显高于正常组,脂滴含量测定与前者一致(P<0.01)。模型组细胞ATF、CHOP基因表达水平均显著升高(P<0.01)。与模型组比较,冠心康组和辛伐他汀组细胞ATF、CHOP基因表达水平均显著降低(P<0.01)。PERK磷酸化以及CHOP蛋白表达水平在冠心康和辛伐他汀干预组表现为显著下调,与模型组比较,差异具有统计学意义(P<0.05)。结论 冠心康可能通过调控PERK-eIF2α-CHOP通路相关基因及蛋白,减少泡沫细胞形成,从而减轻内质网应激,维持细胞内胆固醇稳态,减少细胞内胆固醇沉积。 相似文献
3.
4.
Matrine,oxymatrine, and compound Kushen injection from the roots of Sophora flavescens: an overview of their anticancer activities 下载免费PDF全文
In the present review, we updated current information on the chemistry, contents, and anticancer properties of matrine (MT), oxymatrine (OMT), and compound Kushen injection (CKI). The anticancer properties were focused on lung, breast, and liver cancer cells because they are most susceptible. Sources of information were from Google, Google Scholar, PubMed, PubMed Central, Science Direct, PubChem, J-Stage, Directory of Open Access Journals (DOAJ), and China National Knowledge Infrastructure (CNKI). Reference was also made on botanical websites, such as Flora of China and World Flora Online. MT and OMT are dominant quinolizidine alkaloids from the roots of Sophora flavescens (Kushen) of the family Fabaceae. Against lung, breast, and liver cancer cells, MT and OMT inhibit cell proliferation; induce cell cycle arrest, apoptosis, and autophagy; restrict angiogenesis; and inhibit cell metastasis, invasion, and migration. The processes involve various molecular targets and signaling pathways. CKI is a traditional Chinese medicine (TCM) composed of root extracts of S. flavescens and Smilax glabra (Baituling) of the family Smilacaceae. With MT and OMT as major components, CKI has been approved for the treatment of cancer in China more than 20 years ago. In recent years, systematic reviews and meta-analysis have been undertaken to evaluate the anticancer effects of CKI. When CKI is used alone and in combination with chemotherapy of western medicine, there is much to be learned concerning their interactions besides their individual and integrated efficacy. Some perspectives of MT, OMT, and CKI are discussed, and their suggestions for future research are provided. 相似文献
5.
摘要:目的:探讨超声造影(CEUS)定量分析对常规超声联合CEUS定性诊断误诊为恶性的甲状腺结节与甲状腺乳头状癌的鉴别诊断价值。方法:选取2018年7月至2021年11月在我院超声科行甲状腺常规超声及CEUS检查,术前联合超声诊断为恶性(C-TIRADS≥4b 或 CEUS 表现为低增强和快速消退任一征像)而病理为良性的35位患者共35个结节为研究组;选择同期联合超声诊断与病理一致的甲状腺乳头状癌患者47例做为对照组。分析常规超声及CEUS特征,并将结节整体、中央部、边缘部及邻近正常甲状腺实质作为感兴趣区分别绘制时间-强度曲线(TIC)进行定量分析,比较两组结节各定量参数之间的差异。结果:研究组整体相对上升时间(△RT)以0.45为截断值,诊断恶性结节的敏感度为97.9%,特异度为85.7%,受试者工作(ROC)曲线下面积为0.96;研究组中央区△RT以0.55为截断值,诊断恶性结节的敏感度为95.7%,特异度为82.9%,ROC曲线下面积为0.87;研究组边缘区△RT以0.25为截断值,诊断恶性结节的敏感度为89.4%,特异度为77.1%,ROC曲线下面积为0.89。结论:CEUS定量分析在常规超声联合CEUS定性误诊甲状腺结节的诊断中具有一定的鉴别诊断价值。 相似文献
6.
Ahmad Adebayo Irekeola Engku Nur Syafirah E.A.R. Yusuf Wada Rohimah Mohamud Norhafiza Mat Lazim Chan Yean Yean Rafidah Hanim Shueb 《Indian journal of medical microbiology》2022,40(3):420-426
BackgroundEpstein-Barr virus (EBV) is a member of the herpesvirus family that is known to ubiquitously infect people worldwide. However, the actual prevalence of EBV infection in diseased patients in Nigeria, remains unknown. This study was thus conducted to ascertain the true prevalence.MethodsA systematic review and meta-analysis of published data was conducted according to the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). Electronic databases including PubMed, Scopus, ScienceDirect, and Google Scholar were searched for studies reporting the occurrence of EBV infection among patients with established diseases. Studies were included if they assessed EBV infection in diseased patients in Nigeria. Data were extracted and subsequently analysed using R software. Funnel plot and Egger's regression test was used to assess publication bias, while JBI prevalence tool was used to assess study quality.ResultsA total of 13 studies covering 228 cases of EBV infection among 1157 diseased patients were included. Summary estimates were computed using random-effects model. The pooled prevalence of EBV infection was 20.3% (95% CI: 10.8–34.9, I2 ?= ?92.26, p ?< ?0.001). When stratified according to the type of disease, higher estimates were obtained for patients suffering from Kaposi's sarcoma (98.7%, 95% CI: 82.2–99.9) and Nasopharyngeal malignancy (85.7%, 95% CI: 70.0–93.9). A prevalence of 13.4% (95% CI: 6.0–27.4) and 12.2% (95% CI: 4.8–27.8) was derived for the most reported patient populations, lymphoma and HIV, respectively.ConclusionThis first meta-analysis on the prevalence of EBV among Nigerian patients suffering from various diseases reveals a prevalence that emphasises the need to routinely monitor EBV infection in all EBV-associated diseases in Nigeria. 相似文献
7.
Yang Yang Shu Jing Mu Jing He Qiang Chen Fang Hu Yan Zhen Xiaofang 《Clinical rheumatology》2022,41(12):3783-3790
Clinical Rheumatology - To analyze and summarize the clinical features, diagnosis, and treatment of children with Henoch-Schönlein purpura (HSP) complicated by overt gastrointestinal bleeding... 相似文献
8.
Li-Mei Wang Xiao-Meng Chen Hai-Jing Yan Shu Yan Xiao-Yan Sun Da-Wei Zhang Hua Yang Dan-Li Lu Cheng-Ye Che 《国际眼科》2022,15(4):541-546
AIM: To investigate whether non-canonical autophagy transport receptor cell cycle progression 1 (CCPG1) is involved in the corneal antifungal immune response.
METHODS: Human corneal epithelial cells (HCECs) and human myeloid leukemia mononuclear cells (THP-1) macrophages stimulated by Aspergillus fumigatus (A. fumigatus) were used as cell models. The expression of CCPG1 mRNA was detected by qRT-PCR. Western blot was used to determine the protein expression of CCPG1 and interleukin-1β (IL-1β). The dectin-1 neutralizing antibody was used to detect the association between dectin-1 and CCPG1. Immunofluorescence was used to observe the colocalization of CCPG1 and C-type lectin-like receptor-1 (CLEC-1) in THP-1 macrophages.
RESULTS: The expression of CCPG1 started to increase at 4h after infection and increased in a time-dependent manner in HCECs and THP-1 macrophages. With dectin-1 neutralizing antibody pretreatment, the expression of IL-1β was down-regulated. CCPG1 up-regulation in response to A. fumigatus infection was independent of dectin-1. Immunofluorescence showed the colocalization of CCPG1 and CLEC-1 in THP-1 macrophages.
CONCLUSION: As a specific autophagy protein of non-canonical autophagy pathway, CCPG1 is involved in corneal infection with A. fumigatus. 相似文献
9.
10.
Hyun Cheol Chung MD PhD Yoon-Koo Kang MD PhD Zhendong Chen MD Yuxian Bai MD Wan Zamaniah Wan Ishak MD Byoung Yong Shim MD Young Lee Park MD Dong-Hoe Koo MD PhD Jianwei Lu MD Jianming Xu MD Hong Jae Chon MD Li-Yuan Bai MD Shan Zeng MD Ying Yuan MD Yen-Yang Chen MD Kangsheng Gu MD Wen Yan Zhong PhD Shu Kuang MD Chie-Schin Shih MD Shu-Kui Qin MD PhD 《Cancer》2022,128(5):995-1003