全文获取类型
收费全文 | 950篇 |
免费 | 66篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 28篇 |
妇产科学 | 6篇 |
基础医学 | 99篇 |
口腔科学 | 2篇 |
临床医学 | 49篇 |
内科学 | 285篇 |
皮肤病学 | 100篇 |
神经病学 | 16篇 |
特种医学 | 40篇 |
外科学 | 121篇 |
综合类 | 131篇 |
预防医学 | 24篇 |
眼科学 | 14篇 |
药学 | 44篇 |
中国医学 | 2篇 |
肿瘤学 | 60篇 |
出版年
2022年 | 4篇 |
2021年 | 16篇 |
2020年 | 16篇 |
2019年 | 22篇 |
2018年 | 18篇 |
2017年 | 23篇 |
2016年 | 21篇 |
2015年 | 23篇 |
2014年 | 33篇 |
2013年 | 29篇 |
2012年 | 49篇 |
2011年 | 55篇 |
2010年 | 31篇 |
2009年 | 33篇 |
2008年 | 29篇 |
2007年 | 26篇 |
2006年 | 57篇 |
2005年 | 36篇 |
2004年 | 38篇 |
2003年 | 19篇 |
2002年 | 24篇 |
2001年 | 33篇 |
2000年 | 18篇 |
1999年 | 23篇 |
1998年 | 35篇 |
1997年 | 38篇 |
1996年 | 27篇 |
1995年 | 9篇 |
1994年 | 11篇 |
1993年 | 10篇 |
1992年 | 16篇 |
1991年 | 15篇 |
1990年 | 15篇 |
1989年 | 14篇 |
1988年 | 17篇 |
1987年 | 12篇 |
1986年 | 12篇 |
1985年 | 19篇 |
1984年 | 7篇 |
1983年 | 10篇 |
1982年 | 12篇 |
1981年 | 10篇 |
1980年 | 11篇 |
1979年 | 9篇 |
1978年 | 6篇 |
1977年 | 7篇 |
1975年 | 5篇 |
1972年 | 3篇 |
1969年 | 3篇 |
1968年 | 3篇 |
排序方式: 共有1024条查询结果,搜索用时 31 毫秒
1.
2.
3.
4.
The synthesis and localization of alternatively spliced fibronectin EIIIB in resting and thrombin-treated megakaryocytes 总被引:1,自引:1,他引:0
There are several species of alternatively spliced fibronectin (FN). One of these, FN EIIIB, is primarily present in embryonic and in proliferating and migrating cells and is believed to be important for cell maturation. We have studied the synthesis, localization, and secretion of this FN isoform in isolated guinea pig megakaryocytes, nonmegakaryocytic bone marrow cells, and platelets. There was 7.5 times more general FN in megakaryocytes than in nonmegakaryocytic cells based on the analysis of equivalent amounts of protein. FN EIIIB was detected by Western blotting in megakaryocytes but not in nonmegakaryocytic cells present in bone marrow. Neither megakaryocytes nor platelets secreted FN EIIIB, while megakaryocytes secreted 25.3% +/- 4.6% general FN and platelets secreted about 61% general FN in response to thrombin. Analysis of immunostained cells by confocal microscopy revealed that FN EIIIB had been redistributed to the surface of megakaryocytes in response to thrombin. Synthesis was studied by metabolic labeling, and megakaryocytes were shown to synthesize FN and FN EIIIB. Thus, megakaryocytes and platelets are among a small number of adult cells and tissues that synthesize and contain FN EIIIB. The expression of FN EIIIB on the megakaryocyte surface may influence migration and maturation. 相似文献
5.
6.
P Temesvari J Denburg S Denburg R Carbotte W Bensen D Singal 《Clinical immunology and immunopathology》1983,28(2):243-251
The pathogenesis of neuropsychiatric (NP) SLE remains speculative. A relationship between circulating brain cross-reactive lymphocyte antibodies (LCA) and NP-SLE has been postulated but serial, prospective study of LCA in individual patients with SLE has rarely been performed. In the current study a group of 34 patients with SLE was analyzed using clinical, neurologic, psychiatric, and neuropsychological examinations, together with routine serological tests, to define NP-SLE. Previous history of alloimmunization was also recorded. LCA were measured by a two-stage microcytotoxicity assay against a panel of 25 normal donor B and T cells, at both 40 and 37 degrees C. LCA by this method were found in the serum of 20/34 (58%) SLE, 2/22 (9%) rheumatoid arthritis, and 3/24 (12%) antinuclear-antibody-positive chronic psychiatric patients (P less than 0.01). Analysis of LCA serially in individual SLE patients revealed: (1) No difference in B- or T-cell reactivity at either 4 or 37 degrees C, (2) no significant correlation between previous alloimmunization and the presence of LCA, (3) fluctuations in LCA associated with NP-SLE relapses or remissions, but not with therapy, in 10 patients prospectively studied. A significant positive association was found between the occurrence of single neuropsychiatric events and serial LCA determinations in 180 sera (P less than 0.000001). LCA as measured in this study appear more frequently in SLE than in controls and may indicate active NP-SLE in some patients. Further study of the pathogenic role and diagnostic value of LCA in NP-SLE, including their relationship to subtle neurocognitive changes, is proposed. 相似文献
7.
The dose-dependent cardiomyopathy and heart failure due to adriamycin have been shown to be due to increased oxidative stress and loss of myocytes. We examined the incidence of myocardial apoptosis as well as changes in the expression of apoptotic regulatory gene products in an established animal model of adriamycin cardiomyopathy. Rats were treated with adriamycin (cumulative dose, 15 mg/kg), and the hearts were examined for apoptosis as well as expression of Bax, caspase 3, and Bcl-2 at 0, 4, 10, 16, and 21 days after the treatment. A significant increase in the incidence of apoptosis was seen at 4 days, followed by a decline at 10 and 16 days of posttreatment. At 21 days, the number of apoptotic cells increased again and included cells of the conducting system. Expression of Bax corresponded to these biphasic changes, whereas the converse was true for the expression of Bcl-2. The latter peaked at 10 days followed by a decline at 16 and 21 days. The Bax/Bcl-2 ratio also correlated with the incidence of apoptosis. Expression of caspase 3 correlated with increased apoptosis, but only at early time points. Probucol (cumulative dose, 120 mg/kg), a known antioxidant as well as promoter of endogenous antioxidants, significantly reduced the incidence of apoptosis as well as expression of Bax. Adriamycin-induced hemodynamic changes were also prevented by probucol. These data suggest that adriamycin-induced apoptosis is mediated by oxidative stress and may play a role in the development of heart failure. 相似文献
8.
S CHAUDHURY PK CHAKRABORTY P BHARADWAJ M AUGUSTINE 《Medical Journal Armed Forces India》1994,50(1):59-60
A rare case of viral encephalitis in an 18 year old recruit who presented with signs of catatonic schizophrenia is reported.KEY WORDS: Viral encephalitis, Catatonic schizophrenia 相似文献
9.
Role of epidural medication through caudal route was studied in 109 patients having lumbago with or without sciatica to highlight the value of this mode of treatment which relieved symptoms in more than 70% of cases without hospitalisation and without being off work for long periods as in usual methods of conservative treatment.KEY WORDS: Epidural medication, Backache, Lumbago, Sciatica 相似文献
10.
Wollin TA Singal RK Whelan T Dicecco R Razvi HA Denstedt JD 《Journal of endourology / Endourological Society》1999,13(10):739-744
BACKGROUND AND PURPOSE: The treatment options available for managing bladder calculi include transurethral cystolithotripsy, open cystolithotomy, and shockwave lithotripsy. For larger calculi, transurethral treatment can be time consuming, and the manipulation has the potential to cause urethral injury. Percutaneous suprapubic cystolithotripsy represents another treatment option for bladder calculi which is effective and minimally invasive. PATIENTS AND METHODS: Fifteen patients had bladder calculi treated with percutaneous cystolithotripsy over a 3-year period. The mean stone size was 39 mm (range 10-64 mm). Stones were single in seven patients and multiple in eight patients. The indications for cystolithotripsy were stone size >3 cm, multiple stones >1 cm, and inability to perform transurethral cystolithotripsy because of patient anatomy. Percutaneous suprapubic cystolithotripsy was done through either a 30F or a 36F cystotomy tract. Fragmentation and removal was performed with a 26F rigid nephroscope and the pneumatic Swiss Lithoclast. Suprapubic and urethral catheters were placed postoperatively in all patients. RESULTS: Each patient was cleared of the stone burden with a single procedure, and there were no major complications. The mean duration of suprapubic catheterization was 2.6 (range 1-5) days. CONCLUSION: Percutaneous suprapubic cystolithotripsy is an effective and safe technique for treating large bladder calculi. It is minimally invasive, avoids urethral injury, and, in combination with the pneumatic Swiss Lithoclast, can be used to fragment and remove large and hard bladder calculi. 相似文献