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991.
目的:探究人巨细胞病毒(HCMV)UL111A基因在增殖性感染不同时间点的转录本特征及变化。方法:在HCMV AD169株感染人包皮成纤维细胞(HFF)12 h,24 h,48 h,3 d,5 d,7 d,9 d等不同时间点,抽提RNA,反转录成cDNA,PCR检测UL111A转录本特征。扩增产物通过克隆、测序验证不同时间点UL111A转录本的特征变化。利用真核表达载体pcDNA3.1构建UL111A 3种转录本编码区序列载体pcDNA3.1-cmvIL-10,pcDNA3.1-LAcmvIL-10以及pcDNA3.1-unspliced,Western blot验证构建的载体在293T细胞中的有效表达。结果:感染HCMV AD169株的HFF可以检测到cmvIL-10,LAcmvIL-10以及未剪切3种形式转录本。未剪切形式转录本占比最多,cmvIL-10转录本占比最少。在感染的24 h和9 d 3种转录本都有检测到,而在其他时间点未能检测到cmvIL-10 转录本。此外,3 种转录本的编码区序列在293T细胞中均可有效表达。结论:HCMVUL111A基因在增殖性感染不同时间点存在3种形式的转录本。 相似文献
992.
目的比较超声、Er,Cr:YSGG激光及Er:YAG激光辅助1%次氯酸钠(NaOCl)溶液冲洗对人离体牙根管表面粪肠球菌生物膜及根尖区不同深度牙本质小管内粪肠球菌的杀灭效果。
方法单直根管下颌前磨牙42颗,建立粪肠球菌生物膜感染的根管模型,采用随机字表法随机抽取2颗确定建成粪肠球菌生物膜感染根管模型,剩余40颗牙采用随机数字表法按随机对照原则分为5组,每组8颗。A组:5.25% NaOCl联合17%乙二胺四乙酸(EDTA)注射器冲洗;B组:0.9%氯化钠溶液注射器冲洗;C组:1% NaOCl溶液超声荡洗;D组:1% NaOCl溶液Er:YAG激光活化冲洗;E组:1% NaOCl溶液Er,Cr:YSGG激光活化冲洗。按分组进行处理后取样菌落计数,计算灭菌率。使用SPSS 17.0统计软件对实验数据进行方差齐性及正态性检验比较各组间和组内的灭菌率。
结果(1)组间比较:对根管壁表面,各组冲洗方法灭菌率比较,B组(5.74%)相似文献
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994.
Ying Liang Fang Xie Xinyuan Tang Mei Wang Enmin Zhang Zhikai Zhang Hong Cai Yanhua Wang Xiaona Shen Hongqun Zhao Dongzheng Yu Lianxu Xia Rong Hai 《The American journal of tropical medicine and hygiene》2014,91(4):722-728
The Yersinia pestis chromosome contains a large variety and number of insert sequences that have resulted in frequent chromosome rearrangement events. To identify the chromosomal rearrangement features of Y. pestis strains from five typical plague foci in China and study spontaneous DNA rearrangements potentially stabilized in certain lineages of Y. pestis genomes, we examined the linking mode of locally collinear blocks (LCBs) in 30 Y. pestis strains by a polymerase chain reaction-based method. Our results suggest most strains have relatively stable chromosomal arrangement patterns, and these rearrangement characteristics also have a very close relationship with the geographical origin. In addition, some LCB linking modes are only present in specific strains. We conclude Y. pestis chromosome rearrangement patterns may reflect the genetic features of specific geographical areas and can be applied to distinguish Y. pestis isolates; furthermore, most of the rearrangement events are stable in certain lineages of Y. pestis genomes. 相似文献
995.
996.
Linyuan Wang Cynthia T. Luk Stephanie A. Schroer Alannah M. Smith Xie Li Erica P. Cai Herbert Gaisano Patrick E. MacDonald Zhenyue Hao Tak W. Mak Minna Woo 《Diabetologia》2014,57(9):1889-1898
Aims/hypothesis
Diabetes mellitus represents a significant burden on the health of the global population. Both type 1 and type 2 diabetes share a common feature of a reduction in functional beta cell mass. A newly discovered ubiquitination molecule HECT, UBA and WWE domain containing 1, E3 ubiquitin protein ligase (HUWE1 [also known as MULE or ARF-BP1]) is a critical regulator of p53-dependent apoptosis. However, its role in islet homeostasis is not entirely clear.Methods
We generated mice with pancreas-specific deletion of Huwe1 using a Cre-loxP recombination system driven by the Pdx1 promoter (Pdx1cre + Huwe1 fl/fl) to assess the in vivo role of HUWE1 in the pancreas.Results
Targeted deletion of Huwe1 in the pancreas preferentially activated p53-mediated beta cell apoptosis, leading to reduced beta cell mass and diminished insulin exocytosis. These defects were aggravated by ageing, with progressive further decline in insulin secretion and glucose homeostasis in older mice. Intriguingly, Huwe1 deletion provided protection against genotoxicity, such that Pdx1cre + Huwe1 fl/fl mice were resistant to multiple-low-dose-streptozotocin-induced beta cell apoptosis and diabetes.Conclusion/interpretation
HUWE1 expression in the pancreas is essential in determining beta cell mass. Furthermore, HUWE1 demonstrated divergent roles in regulating beta cell apoptosis depending on physiological or genotoxic conditions. 相似文献997.
Priscilla Mantik Minli Xie Harvey Wong Hank La Ronald W. Steigerwalt Uday Devanaboyina Geoffrey Ganem Danny Shih John A. Flygare Wayne J. Fairbrother Paroma Chakravarty David Russell Gilberto E. Fernandez Ajit S. Narang 《Journal of pharmaceutical sciences》2019,108(6):1934-1943
Solubilization of new chemical entities for toxicity assessment must use excipients that do not negatively impact drug pharmacokinetics and toxicology. In this study, we investigated the tolerability of a model freebase compound, GDC-0152, solubilized by pH adjustment with succinic acid and complexation with hydroxypropyl-β-cyclodextrin (HP-β-CD) to enable intravenous use. Solubility, critical micelle concentration, and association constant with HP-β-CD were determined. Blood compatibility and potential for hemolysis were assessed in vitro. Local tolerability was assessed after intravenous and subcutaneous injections in rats. A pharmacokinetic study was conducted in rats after intravenous bolus administration.GDC-0152 exhibited pH-dependent solubility that was influenced by self-association. The presence of succinic acid increased solubility in a concentration-dependent manner. HP-β-CD alone also increased solubility, but the extent of solubility enhancement was significantly lower than succinic acid alone. Inclusion of HP-β-CD in the solution of GDC-0152 improved blood compatibility, reduced hemolytic potential by ~20-fold in vitro, and increased the maximum tolerated dose to 80 mg/kg. 相似文献
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