首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   4018篇
  免费   190篇
  国内免费   9篇
耳鼻咽喉   19篇
儿科学   78篇
妇产科学   59篇
基础医学   480篇
口腔科学   114篇
临床医学   271篇
内科学   1016篇
皮肤病学   73篇
神经病学   300篇
特种医学   171篇
外科学   611篇
综合类   22篇
预防医学   106篇
眼科学   53篇
药学   321篇
中国医学   6篇
肿瘤学   517篇
  2023年   28篇
  2022年   49篇
  2021年   93篇
  2020年   38篇
  2019年   50篇
  2018年   99篇
  2017年   58篇
  2016年   53篇
  2015年   74篇
  2014年   108篇
  2013年   127篇
  2012年   193篇
  2011年   176篇
  2010年   93篇
  2009年   84篇
  2008年   172篇
  2007年   171篇
  2006年   171篇
  2005年   190篇
  2004年   177篇
  2003年   185篇
  2002年   190篇
  2001年   105篇
  2000年   130篇
  1999年   111篇
  1998年   59篇
  1997年   44篇
  1996年   44篇
  1995年   43篇
  1994年   45篇
  1993年   29篇
  1992年   100篇
  1991年   98篇
  1990年   81篇
  1989年   81篇
  1988年   93篇
  1987年   64篇
  1986年   70篇
  1985年   72篇
  1984年   39篇
  1983年   54篇
  1982年   15篇
  1981年   19篇
  1979年   29篇
  1977年   20篇
  1973年   17篇
  1972年   20篇
  1971年   15篇
  1967年   17篇
  1966年   14篇
排序方式: 共有4217条查询结果,搜索用时 0 毫秒
1.

Objective

This study assessed the association between the timing of first epinephrine administration (EA) and the neurological outcomes following out-of-hospital cardiac arrests (OHCAs) with both initial shockable and non-shockable rhythms.

Methods

This was a post-hoc analysis of a multicenter prospective cohort study (SOS-KANTO 2012), which registered OHCA patients in the Kanto region of Japan from January 2012 to March 2013. We included consecutive adult OHCA patients who received epinephrine. The primary result included 1-month favorable neurological outcomes defined as cerebral performance category (CPC) 1 or 2. Secondary results included 1-month survival and return of spontaneous circulation (ROSC) after arrival at the hospital. Multivariable logistic regression analysis determined the association between delay per minute of the time from call to first EA in both pre- or in-hospital settings and outcomes.

Results

Of the 16,452 patients, 9344 were eligible for our analyses. In univariable analysis, the delay in EA was associated with decreased favorable neurological outcomes only when the initial rhythm was a non-shockable rhythm. In multivariable analyses, delay in EA was associated with decreased ROSC (adjusted odds ratio [OR] for one minute delay, 0.97; 95% confidence interval [CI], 0.96–0.98) and 1-month survival (adjusted OR, 0.95; 95% CI, 0.92–0.97) when the initial rhythm was a non-shockable rhythm, whereas during a shockable rhythm, delay in EA was not associated with decreased ROSC and 1-month survival.

Conclusions

While assessing the effectiveness of epinephrine for OHCA, we should consider the time-limited effects of epinephrine. Additionally, consideration of early EA based on the pathophysiology is needed.  相似文献   
2.
AIM: To investigate the participation of adenosine receptors in the adenosine 5'-triphosphate (ATP)-induced relaxation in the corpus cavernosum penis (CCP) of rabbits. METHODS: The ATP-induced relaxation was assessed on the noradrenaline precontracted CCP of rabbits in the presence and absence of 8-(3-chlorostyryl)caffeine (CSC); an adenosine A(2A) receptor antagonist; alloxazine and MRS1754; adenosine A(2B) receptor antagonists; and ARL67156, an inhibitor of ecto-nucleoside triphosphate diphosphohydrolases. RESULTS: Adenosine and ATP relaxed the noradrenaline precontracted CCP of rabbits in a concentration-dependent manner. The adenosine- and ATP-induced relaxations were suppressed by alloxazine and MRS1754, but not by 8-(3-chlorostyryl)caffeine. ARL67156 potentiated the ATP-induced relaxation but not the adenosine-induced one. MRS1754 suppressed the ATP-induced relaxation potentiated by ARL67156. CONCLUSIONS: The above results suggest that, in the CCP of rabbits, the adenosine receptor mediating adenosine-induced relaxation is of the A(2B) receptor and the ATP directly causes relaxation through the A(2B) receptor on the CCP.  相似文献   
3.
Histamine-type 2 antagonists (H2-blockers) as represented by cimentidine have been shown to adversely affect renal allograft function, particularly when coadministered with cyclosporine, currently a major immunosuppressant. To determine whether or not a newer and more powerful H2-blocker, famotidine, would produce similar adverse effects, we assessed seven cyclosporine-treated renal allograft recipients with regard to changes in their renal function on or off the H2-blocker over a one-week period. Neither the administration nor withdrawal of famotidine (20–40 mg/day) resulted in any significant changes in serum creatine, BUN, urine output or cyclosporine trough levels, suggesting that famotidine can be safely administered as an H2-blocker to cyclosporine-treated renal allograft recipients.  相似文献   
4.
Coiled bodies and interfascicular threads are conspicuous white matter abnormalities of brains of patients with progressive supranuclear palsy (PSP). Both structures are argyrophilic and immunoreactive for the microtubule-binding protein tau. This report concerns the ultrastructural localization of interfascicular threads and their relationship to coiled bodies in five PSP patients. We showed for the first time that abnormal tubules with a 13- to 15-nm diameter and fuzzy outer contours were the common structures of coiled bodies in the oligodendroglial perikarya and of interfascicular threads. Moreover, the tubules were immunolabeled by anti-tau antibodies. The abnormal tau-positive tubules of interfascicular threads were located in the inner loop of the myelin sheath. Our study further indicated that the thread-like structures in the white matter comprised, at least in part, oligodendroglial processes, and that they were also present in gray matter. We consider that the formation of coiled bodies in the perikarya and of interfascicular threads represents a common cytoskeletal abnormality of the oligodendroglia of PSP patients. Moreover, even though the white matter alterations of PSP resemble those of corticobasal degeneration, there are certain ultrastructural differences in the abnormal oligodendroglial tubules of the two diseases. Received: 4 October 1996 / Accepted: 6 December 1996  相似文献   
5.
6.
1. The effects of acute bilateral superior cervical ganglionectomy on cerebral blood flow and metabolism were investigated in stroke-prone spontaneously hypertensive rats (SHRsp), before and during cerebral ischaemia. 2. The resting cerebral blood flow was comparable between the control and denervated animals. 3. There was no significant difference in cerebral blood flow or concentration of tissue energy metabolites (adenosine triphosphate [ATP], lactate and pyruvate) between the sham-operated control and denervated animals during ischaemia. 4. The results suggest that sympathetic innervation of cerebral vessels originating from superior cervical ganglia may not play a major role in the progression of cerebral ischaemia in SHRsp.  相似文献   
7.
A human monoclonal antibody (MCA), CLN-IgG, showed cytotoxic effect in vitro against the cervical carcinoma cell line, ME-180, by antibody dependent cell-mediated cytotoxicity (ADCC). To determine which fractions of cells in peripheral blood lymphocyte (PBL) mediate ADCC, PBL were separated with nylon wool column and sheep red blood cells (SRBC). Both adherent cells (monocyte) and non-T, non-B cells showed cytotoxicity by ADCC. Human non-T, non-B cells showed higher cytotoxic activity against ME-180 cells than monocytes. Furthermore murine effector cells were less effective in ADCC than human effector cells with human MCA.  相似文献   
8.
9.
S Nagao 《Neuroreport》1992,3(1):13-16
Responses of Purkinje cells were compared in the monkey flocculus and ventral paraflocculus. During vestibuloocular reflex (VOR) eye movements, flocculus Purkinje cells exhibited simple spike modulation related to head velocity, while ventral paraflocculus Purkinje cells exhibited modulation with no such head velocity preference. During smooth tracking of a sinusoidally moving small target, ventral paraflocculus Purkinje cells exhibited simple spike modulation related to target velocity or position, while the flocculus Purkinje cells exhibited a smaller modulation with no such target preference. Visual suppression of the VOR enhanced the simple spike responses in the ventral paraflocculus, but not in the flocculus. These results suggest that the primate flocculus and the ventral paraflocculus control differentially VOR and smooth pursuit eye movements, respectively.  相似文献   
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号