全文获取类型
收费全文 | 630455篇 |
免费 | 306756篇 |
国内免费 | 58753篇 |
专业分类
耳鼻咽喉 | 5756篇 |
儿科学 | 8501篇 |
妇产科学 | 7019篇 |
基础医学 | 138884篇 |
口腔科学 | 9221篇 |
临床医学 | 109927篇 |
内科学 | 148861篇 |
皮肤病学 | 8723篇 |
神经病学 | 41096篇 |
特种医学 | 22164篇 |
外国民族医学 | 231篇 |
外科学 | 79066篇 |
综合类 | 114920篇 |
现状与发展 | 88篇 |
一般理论 | 38篇 |
预防医学 | 65716篇 |
眼科学 | 26722篇 |
药学 | 97476篇 |
343篇 | |
中国医学 | 65010篇 |
肿瘤学 | 46202篇 |
出版年
2023年 | 8017篇 |
2022年 | 18408篇 |
2021年 | 22598篇 |
2020年 | 19969篇 |
2019年 | 24858篇 |
2018年 | 26207篇 |
2017年 | 25710篇 |
2016年 | 23623篇 |
2015年 | 29182篇 |
2014年 | 33090篇 |
2013年 | 31279篇 |
2012年 | 40617篇 |
2011年 | 44759篇 |
2010年 | 35578篇 |
2009年 | 39221篇 |
2008年 | 32035篇 |
2007年 | 28994篇 |
2006年 | 27997篇 |
2005年 | 27660篇 |
2004年 | 22868篇 |
2003年 | 21517篇 |
2002年 | 19833篇 |
2001年 | 20442篇 |
2000年 | 16128篇 |
1999年 | 21299篇 |
1998年 | 19285篇 |
1997年 | 19080篇 |
1996年 | 18776篇 |
1995年 | 18719篇 |
1994年 | 18020篇 |
1993年 | 15621篇 |
1992年 | 15816篇 |
1991年 | 14669篇 |
1990年 | 13268篇 |
1989年 | 12830篇 |
1988年 | 12185篇 |
1987年 | 11377篇 |
1986年 | 10689篇 |
1985年 | 9521篇 |
1984年 | 7269篇 |
1983年 | 7116篇 |
1982年 | 8016篇 |
1981年 | 7492篇 |
1980年 | 7086篇 |
1979年 | 6975篇 |
1978年 | 6058篇 |
1977年 | 6382篇 |
1976年 | 5955篇 |
1975年 | 5650篇 |
1974年 | 5245篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
61.
Yuan Peng Yuman Li Haiyan Cao Liu Hong Yu Wang Mingxing Xie 《Journal of ultrasound in medicine》2019,38(2):539-544
A pulmonary artery (PA) sling is a very rare congenital cardiovascular anomaly, and only a few studies have reported PA slings in fetuses. The relationship of the PA, aorta, ductus arteriosus, and trachea can be evaluated in the 3‐vessel and 3‐vessel and trachea views during fetal echocardiography. A PA sling can be detected by abnormal positioning of the left PA in relation to the trachea when sweeping from the 3‐vessel view cranially to the 3‐vessel and trachea view. Here we report 3 cases of fetal PA slings and their follow‐ups. Two cases were confirmed by postnatal echocardiography, and the other case was confirmed by a cardiovascular cast after pregnancy termination. We emphasize that the 3‐vessel and 3‐vessel and trachea views are of crucial importance in the prenatal diagnosis of a PA sling. 相似文献
63.
Yuanqing Yao Jun Qian Shunkang Rong Yuwen Huang Bo Xiong Gang Yang Dengqing Zhang Shimin Deng Jie Tan Que Zhu Changming Deng Dichuan Liu Haitao Ran Zhigang Wang Jing Huang 《Ultrasound in medicine & biology》2019,45(2):490-499
Stellate ganglion (SG) modification has been investigated for arrhythmia treatment. In this study, transesophageal SG imaging and intervention were explored using a homemade 30F integrated focused ultrasonic catheter in healthy mongrel canines in vivo. Anatomic details of SGs were ultrasonically imaged and evaluated. SG had a heterogeneous echoic structure and characteristic profiles sketched by hyper-echoic outlines in an ultrasonogram. Left SGs in the experimental group were successfully ablated through the esophagus under ultrasonic guidance provided by the catheter itself. Two weeks after the ablation, the QT and QTc of the experimental group decreased compared with those of the sham group and at baseline (both p values < 0.001). Histologic examination revealed that left SGs were destroyed. No major complications were observed. This approach may be further explored as a method for ganglia remodeling evaluation and as a strategy of ganglia modification for arrhythmia and for other diseases. 相似文献
64.
目的 探讨电针复合靶控输注(Target Controlled Infusion, TCI)在单肺通气食管癌开胸手术麻醉中的应用价值。方法 选取于我院拟行单肺通气食管癌开胸切除手术患者60例作为研究对象。随机将其分为试验组与对照组,对照组30例采取气管插管全麻及TCI靶控输注维持麻醉深度,试验组30例则在对照组方案基础上辅助电针麻醉,记录两组患者手术麻醉时间、药物用量、苏醒时间、并发症;以及术前(TⅠ)、插管前即刻(TⅡ)、插管后1 min(TⅢ)、切皮即刻(TⅣ)、去骨时(TⅤ)、拔管即刻(TⅥ)时平均动脉压(MAP)、平均心率(HR)、BIS值;术前、术后1天、术后3天简易智能精神状态检查量表(MMSE);并于麻醉诱导前(T0)、手术开始2 h(T1)、术后1天(T2)、术后3天(T3)时抽取患者外周静脉血检测IL-1β、IL-6、IL-10、TNF-α浓度。结果 试验组手术用时、麻醉时间略低于对照组,但差异无统计学意义(P>0.05),试验组异丙酚、舒芬太尼用量以及苏醒时间均明显低于对照组(P<0.05);TⅡ时两组平均动脉压(Mean Arterial Pressure, MAP)、心率(Heartrate, HR)较术前明显降低,且试验组MAP明显低于对照组(P<0.05),但两组TⅡ时HR比较无显著差异(P>0.05);TⅢ、TⅥ时对照组MAP、HR明显高于TⅠ时,而试验组MAP、HR与TⅠ比较无显著差异(P>0.05)。术后1天、3天试验组简易智能精神状态检查量表(Mini-Mental State Examination, MMSE)评分低于对照组,有显著性差异(P<0.05)。T1、T2、T3时试验组白介素-1β(IL-1β)、白介素-6(IL-6)、肿瘤坏死因子(Tumor Necrosis Factor-α, TNF-α)水平明显低于对照组(P<0.05),白介素-10(IL-10)水平明显高于对照组(P<0.05)。结论 采用电针复合TCI靶控输注麻醉方案可有效提升单肺通气食管癌开胸手术麻醉效果,能够降低患者术后认知功能障碍发生风险。 相似文献
65.
Peng Cheng Linlin Yang Xiaodan Huang Xuejun Wang Maoqing Gong 《Archiv der Pharmazie》2020,353(4):1900350
Malaria, one of the most striking, re-emerging infectious diseases caused by the genus Plasmodium, places a huge burden on global healthcare systems. A major challenge in the control and eradication of malaria is the continuous emergence of increasingly widespread drug-resistant malaria, creating an urgent need to develop novel antimalarial agents. Chalcone derivatives are ubiquitous in nature and have become indispensable units in medicinal chemistry applications due to their diverse biological profiles. Many chalcone derivatives demonstrate potential in vitro and in vivo antimalarial activity, so chalcone could be a useful template for the development of novel antimalarial agents. This review covers the recent development of chalcone hybrids as antimalarial agents. The critical aspects of the design and structure–activity relationship of these compounds are also discussed. 相似文献
66.
Toidi Adekambi Chris C. Ibegbu Stephanie Cagle Ameeta S. Kalokhe Yun F. Wang Yijuan Hu Cheryl L. Day Susan M. Ray Jyothi Rengarajan 《The Journal of clinical investigation》2015,125(5):1827-1838
BACKGROUND. The identification and treatment of individuals with tuberculosis (TB) is a global public health priority. Accurate diagnosis of pulmonary active TB (ATB) disease remains challenging and relies on extensive medical evaluation and detection of Mycobacterium tuberculosis (Mtb) in the patient’s sputum. Further, the response to treatment is monitored by sputum culture conversion, which takes several weeks for results. Here, we sought to identify blood-based host biomarkers associated with ATB and hypothesized that immune activation markers on Mtb-specific CD4+ T cells would be associated with Mtb load in vivo and could thus provide a gauge of Mtb infection.METHODS. Using polychromatic flow cytometry, we evaluated the expression of immune activation markers on Mtb-specific CD4+ T cells from individuals with asymptomatic latent Mtb infection (LTBI) and ATB as well as from ATB patients undergoing anti-TB treatment.RESULTS. Frequencies of Mtb-specific IFN-γ+CD4+ T cells that expressed immune activation markers CD38 and HLA-DR as well as intracellular proliferation marker Ki-67 were substantially higher in subjects with ATB compared with those with LTBI. These markers accurately classified ATB and LTBI status, with cutoff values of 18%, 60%, and 5% for CD38+IFN-γ+, HLA-DR+IFN-γ+, and Ki-67+IFN-γ+, respectively, with 100% specificity and greater than 96% sensitivity. These markers also distinguished individuals with untreated ATB from those who had successfully completed anti-TB treatment and correlated with decreasing mycobacterial loads during treatment.CONCLUSION. We have identified host blood-based biomarkers on Mtb-specific CD4+ T cells that discriminate between ATB and LTBI and provide a set of tools for monitoring treatment response and cure.TRIAL REGISTRATION. Registration is not required for observational studies.FUNDING. This study was funded by Emory University, the NIH, and the Yerkes National Primate Center. 相似文献
67.
Micro‐evolution of the hepatitis B virus genome in hepatitis B e‐antigen‐positive carriers: Comparison of genotypes B and C at various immune stages 下载免费PDF全文
68.
69.
70.