全文获取类型
收费全文 | 2023篇 |
免费 | 122篇 |
国内免费 | 21篇 |
专业分类
耳鼻咽喉 | 11篇 |
儿科学 | 56篇 |
妇产科学 | 23篇 |
基础医学 | 281篇 |
口腔科学 | 40篇 |
临床医学 | 169篇 |
内科学 | 444篇 |
皮肤病学 | 40篇 |
神经病学 | 218篇 |
特种医学 | 124篇 |
外科学 | 277篇 |
综合类 | 14篇 |
一般理论 | 1篇 |
预防医学 | 114篇 |
眼科学 | 28篇 |
药学 | 199篇 |
中国医学 | 1篇 |
肿瘤学 | 126篇 |
出版年
2022年 | 16篇 |
2021年 | 23篇 |
2020年 | 20篇 |
2019年 | 43篇 |
2018年 | 41篇 |
2017年 | 19篇 |
2016年 | 26篇 |
2015年 | 34篇 |
2014年 | 46篇 |
2013年 | 64篇 |
2012年 | 112篇 |
2011年 | 115篇 |
2010年 | 55篇 |
2009年 | 70篇 |
2008年 | 94篇 |
2007年 | 86篇 |
2006年 | 91篇 |
2005年 | 68篇 |
2004年 | 83篇 |
2003年 | 62篇 |
2002年 | 88篇 |
2001年 | 67篇 |
2000年 | 55篇 |
1999年 | 55篇 |
1998年 | 34篇 |
1997年 | 26篇 |
1996年 | 33篇 |
1994年 | 29篇 |
1993年 | 31篇 |
1992年 | 40篇 |
1991年 | 32篇 |
1990年 | 37篇 |
1989年 | 44篇 |
1988年 | 45篇 |
1987年 | 51篇 |
1986年 | 26篇 |
1985年 | 33篇 |
1984年 | 26篇 |
1983年 | 22篇 |
1982年 | 12篇 |
1981年 | 18篇 |
1980年 | 11篇 |
1979年 | 13篇 |
1978年 | 15篇 |
1977年 | 18篇 |
1976年 | 13篇 |
1975年 | 16篇 |
1974年 | 10篇 |
1973年 | 22篇 |
1972年 | 21篇 |
排序方式: 共有2166条查询结果,搜索用时 15 毫秒
1.
W. Nörenberg Ernst Schöffel Bela Szabo Klaus Starke 《Naunyn-Schmiedeberg's archives of pharmacology》1997,356(2):159-165
The aim of the study was to subclassify the soma-dendritic α2-autoreceptors in the locus coeruleus (LC) of the rat by means of antagonists. To this end, the frequency of spontaneous action
potentials was recorded extracellularly from single LC neurones in brain slices. The neurones fired spontaneously at an average
rate of 1 Hz. The selective α2-adrenoceptor agonist 5-bromo-6-(2-imidazolin-2-ylamino)-quinoxaline (UK 14,304) and noradrenaline decreased the action potential
discharge with IC50 values of 5 and 510 nM, respectively. The concentration-inhibition curves of UK 14,304 and noradrenaline were shifted to the
right by phentolamine (0.15 μM) and rauwolscine (0.15 μM) but not by prazosin (1 μM). Apparent K
d values of phentolamine were 17 nM (against UK 14,304) and 20 nM (against noradrenaline). Apparent K
d values of rauwolscine were 47 nM (against UK 14,304) and 70 nM (against noradrenaline). (+)-Oxaprotiline (1 μM) suppressed
the firing of the neurones within 10 to 33 min. In the continued presence of oxaprotiline, phentolamine and rauwolscine restored
firing with EC50 values of 120 and 250 nM, respectively. Prazosin (1 μM) again was ineffective. All three antagonist affinity estimates –
against UK 14,304, exogenous noradrenaline and endogenous noradrenaline (that accumulates in the extracellular space in the
presence of oxaprotiline) – yield an affinity order phentolamine > rauwolscine >> prazosin, prazosin being ineffective even
at a concentration of 1 μM. These findings identify the soma-dendritic α2-autoreceptors of the LC as the rat variant of the α2A/D-adrenoceptor, i.e. α2D. Not only presynaptic but also soma-dendritic α2-autoreceptors may at least predominantly be α2A/D throughout the nervous system.
Received: 3 March 1997 / Accepted: 21 April 1997 相似文献
2.
3.
4.
Occurrence of the t(2;5)(p23;q35) in non-Hodgkin's lymphoma 总被引:9,自引:3,他引:6
Weisenburger DD; Gordon BG; Vose JM; Bast MA; Chan WC; Greiner TC; Anderson JR; Sanger WG 《Blood》1996,87(9):3860-3868
Primary CD30(Ki-1)-positive anaplastic large-cell lymphoma (ALCL) is considered by some to be a distinct clinicopathologic entity associated with the t(2;5) (p23;q35). However, the specificity of t(2;5) for ALCL has not been carefully studied. Therefore, we performed a detailed analysis of all cases of ALCL with abnormal cytogenetics results in the Nebraska Lymphoma Study Group registry, as well as all other cases of non-Hodgkin's lymphoma with t(2;5) in the registry. We found the t(2;5) in only five of 10 cases of ALCL, four of whom were young patients. However, we also found the t(2;5) in 11 other cases of nonanaplastic lymphoma, including eight children with typical peripheral T-cell lymphomas of various types. The t(2;5) was also found in three older adults with B-cell lymphomas of various types. Thus, the t(2;5) was not specific for CD30+ ALCL. However, t(2;5) may define a clinicopathologic entity in children and young adults characterized by variable morphologies with a T-cell or indeterminate phenotype, CD30-positivity, nodal disease with frequent extranodal involvement, advanced stage, and an excellent response to therapy, including bone marrow transplantation for relapsed disease. The clinical relevance of the t(2;5) in older patients requires further study. 相似文献
5.
6.
Braffman BH; Coleman BG; Ramchandani P; Arger PH; Nodine CF; Dinsmore BJ; Louie A; Betsch SE 《Radiology》1994,190(3):797
7.
8.
9.
Seventy-six patients with severely comminuted distal radial fractures were treated at two institutions, of which the overwhelming majority were Frykman class VIII. Fifteen fractures were open. Thirty patients were seen at the University Hospital; 17 had pins and plaster and 13 had external fixation. Forty-six patients were seen at Kaiser Hospital; all had pins and plaster treatment. The complication rate for those with pins and plaster at the University Hospital was 53%; the complication for external fixation rate was 62%. The affiliated-hospital complication rate was 52%. All patients with ipsilateral forearm shaft and carpal fractures developed a nonunion of the carpal fracture. Few patients maintained anatomic reduction, and many had significant intra-articular malalignment. External fixation with threaded half pins did not obviate pin problems in our series. These methods may help manage severely comminuted distal radial fractures, but complications should be anticipated and alternative treatment considered, especially when ipsilateral carpal or forearm shaft fractures are present. 相似文献
10.
An 89-year-old woman developed an acute carpal tunnel syndrome secondary to hemarthrosis associated with pigmented villonodular synovitis of the wrist. Pigmented villonodular synovitis is rare in a patient of this age and is an unusual cause of carpal tunnel syndrome. 相似文献