全文获取类型
收费全文 | 33678篇 |
免费 | 2079篇 |
国内免费 | 451篇 |
专业分类
耳鼻咽喉 | 662篇 |
儿科学 | 336篇 |
妇产科学 | 543篇 |
基础医学 | 5739篇 |
口腔科学 | 716篇 |
临床医学 | 2735篇 |
内科学 | 6284篇 |
皮肤病学 | 1432篇 |
神经病学 | 2559篇 |
特种医学 | 2181篇 |
外科学 | 4414篇 |
综合类 | 115篇 |
一般理论 | 11篇 |
预防医学 | 1143篇 |
眼科学 | 908篇 |
药学 | 3413篇 |
中国医学 | 462篇 |
肿瘤学 | 2555篇 |
出版年
2024年 | 16篇 |
2023年 | 269篇 |
2022年 | 933篇 |
2021年 | 1443篇 |
2020年 | 661篇 |
2019年 | 961篇 |
2018年 | 1150篇 |
2017年 | 943篇 |
2016年 | 1405篇 |
2015年 | 1869篇 |
2014年 | 2149篇 |
2013年 | 2354篇 |
2012年 | 3458篇 |
2011年 | 3235篇 |
2010年 | 1972篇 |
2009年 | 1572篇 |
2008年 | 2089篇 |
2007年 | 1924篇 |
2006年 | 1674篇 |
2005年 | 1475篇 |
2004年 | 1123篇 |
2003年 | 983篇 |
2002年 | 773篇 |
2001年 | 374篇 |
2000年 | 312篇 |
1999年 | 236篇 |
1998年 | 133篇 |
1997年 | 84篇 |
1996年 | 57篇 |
1995年 | 51篇 |
1994年 | 50篇 |
1993年 | 42篇 |
1992年 | 57篇 |
1991年 | 55篇 |
1990年 | 46篇 |
1989年 | 47篇 |
1988年 | 31篇 |
1987年 | 34篇 |
1986年 | 20篇 |
1985年 | 13篇 |
1984年 | 24篇 |
1983年 | 6篇 |
1982年 | 11篇 |
1981年 | 10篇 |
1979年 | 15篇 |
1978年 | 9篇 |
1977年 | 9篇 |
1976年 | 12篇 |
1974年 | 5篇 |
1969年 | 6篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
The aim of this study was to design a new intravenous blood–gas exchange device and to estimate the design characteristics
of the device with a dimensionless function by using a substance that can be used instead of bovine blood. In addition, the
characteristics of oxygen transfer were estimated using empirical formulas and the reliability of the equations was ascertained
by comparing their output with an experiment performed using bovine blood. The dimensionless function was derived using distilled
water and bovine blood to estimate the oxygen transfer rate. Using the derived equations, the calculated oxygen transfer rates
for bovine blood and distilled water were similar for Reynolds numbers ranging from 0.7 to 7.0. Therefore, it is possible
to estimate the oxygen transfer rate in bovine blood, which is a non-Newtonian fluid, using distilled water, which is a Newtonian
fluid. Moreover, it was possible to verify the related equations because the oxygen transfer rate could be estimated using
the derived equations, according to the diameters of the various device modules. 相似文献
4.
Previously, we prepared two different monoclonal antibodies (mAbs) against human 4-1BB (CD137): an agonistic mAb BBK-1 and an antagonistic mAb BBK-2. In this paper, we describe the molecular cloning of these two mAbs and present comparisons of their amino acid sequences. cDNAs encoding the heavy (H) and light (L) chains of the two mAbs were cloned by screening of cDNA libraries constructed from hybridomas secreting these mAbs. Comparisons of amino acid sequences of the two mAbs showed that, while the constant regions of the H and L chains were identical between the two mAbs, the variable region showed 45% identity in H chains and 48% identity in L chains. This suggests that these two mAbs recognize different epitopes of 4-1BB and may have different effects on the activity of 4-1BB. 相似文献
5.
Outflow of aqueous humor following cyclodialysis or ciliochoroidal detachment in rabbit 总被引:1,自引:0,他引:1
Cyclodialysis and ciliochoroidal detachment were performed in three eyes of three rabbits and in three eyes of another three rabbits, respectively. After aspiration of the aqueous humor, 0.1 ml of 10% sodium fluorescein was injected intracamerally, and the eyeball was enucleated between 30 minutes and one hour after injection and prepared for fluorescence microscopy. Sodium fluorescein concentrations in the supraciliary space were much greater in the group with cyclodialysis or ciliochoroidal detachment than in the normal control group. These results suggest that (1) in the eye with cyclodialysis, the aqueous humor may freely gain access to the supraciliary space through the cleft between the anterior chamber and the supraciliary space and then be removed rapidly and (2) in the eye with ciliochoroidal detachment, the aqueous humor may pass through the uveoscleral outflow pathway. 相似文献
6.
Controlled release of lidocaine hydrochloride from the surfactant-doped hybrid xerogels. 总被引:2,自引:0,他引:2
We investigate the controlled release of lidocaine hydrochloride from the doped silica-based xerogels. In the xerogel preparation, tetraethoxysilane (TEOS), methyltriethoxysilane (MTES), and propyltriethoxysilane (PTES) are used as precursors, and a nonionic surfactant Igepal CO 720 is used as a dopant. The experimental results suggest that the release of lidocaine hydrochloride can be easily controlled by partially substituting TEOS with the organosilanes, and/or by adding the dopant. Adding the organosilane precursors lowers the release of both the drug and the surfactant in the order of TEOS, MTES/TEOS, and PTES/TEOS xerogels. The release from the PTES/TEOS xerogels is much lower than that from the other xerogels. The release of lidocaine hydrochloride is obviously suppressed by the addition of Igepal CO 720, while the release of Igepal CO 720 is slightly promoted by the addition of the drug. The overall release process is found to be diffusion-controlled, and the release behaviors can be well explained by considering the effects of the textual properties of the xerogels and the interactions among the drug, the surfactant, and the xerogel matrices. 相似文献
7.
8.
9.
Chang Y Jung Hyo S Choi Jin S Ju Hyo S Park Tae G Kwon Yong C Bae Dong K Ahn 《The journal of pain》2006,7(10):747-756
The present study investigated the role of central metabotropic glutamate receptors (mGluRs) in interleukin-1beta (IL-1beta)-induced mechanical allodynia and mirror-image mechanical allodynia in the orofacial area. Experiments were carried out on male Sprague-Dawley rats weighing 230 to 280 g. After administration of 0.01, 0.1, 1, or 10 pg of IL-1beta into a subcutaneous area of the vibrissa pad, we examined the withdrawal behavioral responses produced by 10 successive trials of an air-puff ramp pressure applied ipsilaterally or contralaterally to the IL-1beta injection site. Subcutaneous injection of IL-1beta produced mechanical allodynia and mirror-image mechanical allodynia in the orofacial area. Intracisternal administration of CPCCOEt, a mGluR1 antagonist, or MPEP, a mGluR5 antagonist, reduced IL-1beta-induced mechanical allodynia and mirror-image mechanical allodynia. Intracisternal administration of APDC, a group II mGluR agonist, or L-AP4, a group III mGluR agonist, reduced both IL-1beta-induced mechanical allodynia and mirror-image mechanical allodynia. The antiallodynic effect, induced by APDC or L-AP4, was blocked by intracisternal pretreatment with LY341495, a group II mGluR antagonist, or CPPG, a group III mGluR antagonist. These results suggest that groups I, II, and III mGluRs differentially modulated IL-1beta-induced mechanical allodynia, as well as mirror-image mechanical allodynia, in the orofacial area. PERSPECTIVE: Central group I mGluR antagonists and groups II and III mGluR agonists modulate IL-1beta-induced mechanical allodynia and mirror-image mechanical allodynia in the orofacial area. Therefore, the central application of group I mGluR antagonists or groups II and III mGluR agonists might be of therapeutic value in treating pain disorder. 相似文献
10.
Eun Young Jung Hyung Joo Suh Wan Soo Hong Dong Geon Kim Yang Hee Hong In Sun Hong Un Jae Chang 《Nutrition Research》2009,29(7):457-461
Cooking processes that gelatinize granules or disrupt structure might increase the glucose and insulin responses because a disruption of the structure of starch by gelatinization increases its availability for digestion and absorption in the small intestine. We hypothesized that the uncooked form of rice, which has a relatively low degree of gelatinization even though in powder form, would result in lower metabolic glucose and insulin responses compared with cooked rice (CR). To assess the effects of the gelatinization of rice on metabolic response of glucose and insulin, we investigated the glucose and insulin responses to 3 rice meals of different gelatinization degree in female college students (n = 12): CR (76.9% gelatinized), uncooked rice powder (UP; 3.5% gelatinized), and uncooked freeze-dried rice powder (UFP; 5.4% gelatinized). Uncooked rice powders (UP and UFP) induced lower glucose and insulin responses compared with CR. The relatively low gelatinization degree of UPs resulted in low metabolic responses in terms of the glycemic index (CR: 72.4% vs UP: 49.7%, UFP: 59.8%) and insulin index (CR: 94.8% vs UP: 74.4%, UFP: 68.0%). In summary, UPs that were less gelatinized than CR induced low postprandial glucose and insulin responses. 相似文献