全文获取类型
收费全文 | 3971篇 |
免费 | 292篇 |
国内免费 | 23篇 |
专业分类
耳鼻咽喉 | 31篇 |
儿科学 | 149篇 |
妇产科学 | 115篇 |
基础医学 | 441篇 |
口腔科学 | 93篇 |
临床医学 | 319篇 |
内科学 | 870篇 |
皮肤病学 | 58篇 |
神经病学 | 342篇 |
特种医学 | 133篇 |
外国民族医学 | 5篇 |
外科学 | 724篇 |
综合类 | 119篇 |
一般理论 | 1篇 |
预防医学 | 254篇 |
眼科学 | 73篇 |
药学 | 291篇 |
中国医学 | 32篇 |
肿瘤学 | 236篇 |
出版年
2023年 | 38篇 |
2022年 | 89篇 |
2021年 | 144篇 |
2020年 | 94篇 |
2019年 | 114篇 |
2018年 | 142篇 |
2017年 | 89篇 |
2016年 | 101篇 |
2015年 | 115篇 |
2014年 | 164篇 |
2013年 | 190篇 |
2012年 | 260篇 |
2011年 | 290篇 |
2010年 | 183篇 |
2009年 | 159篇 |
2008年 | 195篇 |
2007年 | 208篇 |
2006年 | 202篇 |
2005年 | 245篇 |
2004年 | 192篇 |
2003年 | 173篇 |
2002年 | 153篇 |
2001年 | 76篇 |
2000年 | 68篇 |
1999年 | 80篇 |
1998年 | 27篇 |
1997年 | 26篇 |
1996年 | 17篇 |
1995年 | 30篇 |
1994年 | 16篇 |
1993年 | 19篇 |
1992年 | 28篇 |
1991年 | 20篇 |
1990年 | 27篇 |
1989年 | 21篇 |
1988年 | 18篇 |
1987年 | 17篇 |
1986年 | 24篇 |
1985年 | 20篇 |
1984年 | 17篇 |
1983年 | 12篇 |
1982年 | 14篇 |
1981年 | 11篇 |
1979年 | 12篇 |
1978年 | 21篇 |
1973年 | 11篇 |
1972年 | 14篇 |
1971年 | 11篇 |
1969年 | 15篇 |
1966年 | 10篇 |
排序方式: 共有4286条查询结果,搜索用时 15 毫秒
951.
952.
953.
Sule Berk Ergun Gulistan Sanem Saribas Sait Yarayici Zubeyir Elmazoglu Aziz Cardak Candan Ozogul 《Ocular immunology and inflammation》2020,28(6):888-897
ABSTRACT
Introduction
It was aimed to evaluate the efficacy of two tea tree oil (TTO)-based cleansing gels in chronic blepharitis patients. 相似文献954.
Saritha Aryan Nandita Ghosal Zarina A. Aziz A. S. Hegde Ravi Dadlani 《Brain tumor pathology》2014,31(1):47-50
We present a case of infantile holocord ependymoma in a 4-month-old boy who presented with infection of ventriculoperitoneal shunt done elsewhere for a communicating hydrocephalus. On magnetic resonance imaging, a diffuse holocord T2-hyperintense, T1-hypointense intramedullary bulky lesion with syringomyelia in the cervical level was seen. To the best of our knowledge, this is the first case of infantile holocord ependymoma. As the extent of morbidity associated with a spinal cord tumor is high, an increased level of suspicion and the need for a complete spinal cord screening in a case of infantile hydrocephalus without obvious clinical and radiological evidence of intracranial abnormality is emphasized. 相似文献
955.
Mohammed A. Wahbi F.A. Aalam F.I. Fatiny S.A. Radwan I.Y. Eshan K.H. Al-Samadani 《Saudi Dental Journal》2012,24(2):91-98
ObjectivesThis study was designed to analyze the heat emissions produced by light-curing units (LCUs) of different intensities during their operation. The null hypothesis was that the tested LCUs would show no differences in their temperature rises.MethodsFive commercially available LCUs were tested: a “Flipo” plasma arc, “Cromalux 100” quartz–tungsten–halogen, “L.E. Demetron 1” second-generation light-emitting diode (LED), and “Blue Phase C5” and “UltraLume 5” third-generation LED LCUs. The intensity of each LCU was measured with two radiometers. The temperature rise due to illumination was registered with a type-K thermocouple, which was connected to a computer-based data acquisition system. Temperature changes were recorded in continues 10 and 20 s intervals up to 300 s.ResultsThe Flipo (ARC) light source revealed the highest mean heat emission while the L.E. Demetron 1 LED showing the lowest mean value at 10 and 20 s exposure times. Moreover, Cromalux (QTH) recorded the second highest value for all intervals (12.71, 14.63, 14.60) of heat emission than Blue Phase C5 (LED) (12.25, 13.87, 13.69), interestingly at 20 s illumination for all intervals the highest results (18.15, 19.27, 20.31) were also recorded with Flipo (PAC) LCU, and the lowest (6.71, 5.97, 5.55) with L.E. Demetron 1 LED, while Blue Phase C5 (LED) recorded the second highest value at the 1st and 2nd 20 s intervals (14.12, 11.84, 10.18) of heat emission than Cromalux (QTH) (12.26, 11.43, 10.26). The speed of temperature or heat rise during the 10 and 20 s depends on light intensity of emitted light. However, the QTH LCU was investigated resulted in a higher temperature rise than LED curing units of the same power density.ConclusionThe PAC curing unit induced a significantly higher heat emission and temperature increase in all periods, and data were statistically different than the other tested groups (p < .05). LED (Blue Phase C5) was not statistically significant (p < .05) (at 10 s) than QTH units, also LED (Blue Phase C5, UltraLume 5) generates obvious heat emission and temperature rises than QTH units (at 20 s) except for those which have lower power density of LED curing units (first generation). Thus, the null hypothesis was rejected. 相似文献
956.
Hamzeh Al Zabadi Luc Ferrari Irène Sari-Minodier Marie-Aude Kerautret Aziz Tiberguent Christophe Paris Denis Zmirou-Navier 《Environmental health : a global access science source》2011,10(1):23
Background
Sewage workers are exposed to multiple chemicals among which many are suspected genotoxicants. Therefore, they might incur DNA damage and oxidative stress. We aimed to explore integrated urinary biomarkers, assessing the overall urine genotoxicity by in vitro comet and micronucleus assays and measuring urinary 8-oxo-2'-deoxyguanosine. 相似文献957.
958.
Solmaz Maleki Dizaj Simin Sharifi Elham Ahmadian Aziz Eftekhari Khosro Adibkia 《Expert opinion on drug delivery》2019,16(4):331-345
Introduction: In recent years, the applications of calcium carbonate (CaCO3) nanoparticles (NPs) have gained extensive interest as targeted drug/gene delivery systems to cancerous tissues and cells due to their accessibility, low cost, safety, biocompatibility, pH-sensitivity, and slow biodegradability.
Areas covered: Drug-loaded CaCO3 NPs (CCNPs) have been reviewed. An updated search on the current state of CCNPs as cancer drug/gene delivery systems with a focus on their special properties including pH-sensitivity, biodegradability, and sustained release performance has been also assessed.
Expert opinion: Based on the reviewed literature, CCNPs, because of their superior features, will have a great aiding role in safe and efficient cancer treatment in the near future. 相似文献
959.
Mohamed Talaat Abdel Aziz Mohamed Farid El Asmer Taymour Mostafa Hazem Atta Soheir Mahfouz Hanan Fouad Laila Rashed Dina Sabry Amira Hassouna Ahmed Talaat Abdel Aziz Amira Senbel Ahmed Demery 《The journal of sexual medicine》2009,6(12):3254-3264
IntroductionActivation of the renin‐angiotensin system which is common in diabetes mellitus might affect heme oxygenase (HO‐1) gene expression.AimAssessment of the effects of administration of angiotensin II (Ang II) receptor antagonist (losartan) with HO‐1 inducer or inhibitor on erectile signaling in diabetic rats.Materials and MethodsSeventy male rats were divided equally into seven groups; healthy controls, streptozotocin‐induced diabetic rats, rats on citrate buffer, diabetic rats on losartan, diabetic rats on HO‐1 inducer (cobalt protoporphyrin [CoPP]), diabetic rats on losartan and CoPP, and diabetic rats on losartan and HO‐1 inhibitor (stannus mesoporphyrin [SnMP]).Main Outcome MeasureHO enzyme activity, HO‐1 gene expression, cyclic guanosine monophosphate (cGMP) assay, intracavernosal pressure (ICP), and cavernous tissue sinusoids surface area.ResultsHO‐1 gene expression, HO enzymatic activity, and cGMP were significantly decreased in the cavernous tissue of diabetic rats. These parameters were significantly elevated with the use of CoPP that restored the normal control levels of HO enzyme activity. Administration of losartan exhibited a significant enhancing effect on these parameters compared with the diabetic group, but not restored to the control levels, whereas administration of CoPP combined with losartan led to the restoration of their normal levels. ICP demonstrated significant decline in diabetic rats. The use of CoPP and/or losartan led to its significant improvement compared with diabetic rats. Administration of either losartan and/or CoPP led to a significant increase in the cavernous sinusoids surface area of diabetic rats. Administration of losartan with SnMP significantly decreased the enhancing effect of losartan on the studied parameters.ConclusionThe decline in erectile function in diabetes mellitus could be attributed to the downregulation of HO‐1 gene expression. HO‐1 induction added to Ang II receptor antagonist could improve erectile function. Abdel Aziz MT, El Asmer MF, Mostafa T, Atta H, Mahfouz S, Fouad H, Rashed L, Sabry D, Hassouna A, Abdel Aziz AT, Senbel A, and Demery A. Effects of losartan, HO‐1 inducers or HO‐1 inhibitors on erectile signaling in diabetic rats. 相似文献
960.