全文获取类型
收费全文 | 1021篇 |
免费 | 63篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 18篇 |
妇产科学 | 14篇 |
基础医学 | 70篇 |
口腔科学 | 13篇 |
临床医学 | 108篇 |
内科学 | 271篇 |
皮肤病学 | 15篇 |
神经病学 | 54篇 |
特种医学 | 27篇 |
外国民族医学 | 2篇 |
外科学 | 264篇 |
综合类 | 22篇 |
预防医学 | 57篇 |
眼科学 | 13篇 |
药学 | 66篇 |
中国医学 | 18篇 |
肿瘤学 | 52篇 |
出版年
2023年 | 11篇 |
2022年 | 28篇 |
2021年 | 36篇 |
2020年 | 22篇 |
2019年 | 21篇 |
2018年 | 36篇 |
2017年 | 29篇 |
2016年 | 30篇 |
2015年 | 19篇 |
2014年 | 35篇 |
2013年 | 52篇 |
2012年 | 58篇 |
2011年 | 61篇 |
2010年 | 44篇 |
2009年 | 34篇 |
2008年 | 58篇 |
2007年 | 59篇 |
2006年 | 38篇 |
2005年 | 44篇 |
2004年 | 40篇 |
2003年 | 60篇 |
2002年 | 45篇 |
2001年 | 26篇 |
2000年 | 14篇 |
1999年 | 23篇 |
1998年 | 13篇 |
1997年 | 11篇 |
1996年 | 8篇 |
1995年 | 10篇 |
1994年 | 6篇 |
1993年 | 4篇 |
1992年 | 15篇 |
1991年 | 13篇 |
1990年 | 9篇 |
1989年 | 10篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1984年 | 5篇 |
1983年 | 4篇 |
1982年 | 14篇 |
1981年 | 11篇 |
1980年 | 6篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1976年 | 3篇 |
1975年 | 1篇 |
1974年 | 5篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1959年 | 1篇 |
排序方式: 共有1088条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
Summary— The regulation and role of the intracellular Ca2+ pools were studied in rat peritoneal mast cells. Cytosolic free calcium concentration ([Ca2+ ]i) was monitored in fura-2 loaded mast cells. In the presence of Ca2+ and K+, compound 48/80 induced a biphasic increase in [Ca2+ ]i composed of a fast transient phase and an apparent sustained phase. The sustained phase was partially inhibited by the addition of Mn2+ . DTPA, a cell-impermeant chelator of Mn2+ , reversed this inhibition, suggesting that a quenching of fura-2 fluorescence occurs in the extracellular medium. In the absence of extracellular Ca2+ , the transient phase, but not the sustained one, could be preserved, provided that mast cells were depolarized. The transient phase was completely abolished by thapsigargin, a microsomal Ca2+ -ATPase inhibitor. Maximum histamine release induced by either compound 48/80 or antigen was obtained in the absence of added Ca2+ only when mast cells were depolarized. These histamine releases were inhibited by low doses (< 30 nM) of thapsigargin. Thapsigargin at higher doses induced histamine release which was unaffected by changing the plasma membrane potential, but was completely dependent on extracellular Ca2+ , showing that a Ca2+ influx is required for thapsigargin-induced exocytosis. Together, these results suggest that the mobilization of Ca2+ from thapsigargin sensitive-intracellular pools induced by compound 48/80 or antigen is sufficient to trigger histamine release. The modulation of these pools by the plasma membrane potential suggest their localization is close to the plasma membrane. 相似文献
6.
7.
The introduction of bisphosphonates has increased in the last decade following their indication for metastatic bone diseases,
osteoporosis, hypercalcaemia of malignancy and Paget’s disease. Although bisphosphonates have been used clinically for more
than three decades there have been no documented long-term complications of their effects on the jaws until recently, where
there is now growing evidence of the influence of bisphosphonates on osteonecrosis of the jaws. The aim of this paper is to
report a case of this newly described complication, to review this phenomenon, including the clinical implications and to
reiterate current clinical guidelines for management of patients in which bisphosphonate therapy is indicated. To the best
of our knowledge this is the first reported case of bisphosphonate-induced necrosis of the jaw in South Africa. 相似文献
8.
Modulation of calcium homeostasis as a mechanism for altering smooth muscle responsiveness in asthma
Airway hyperresponsiveness remains a defining characteristic of asthma. Traditional views assert that airway smooth muscle is an important structural effector cell in the bronchi that modulates bronchomotor tone induced by contractile agonists. New evidence, however, suggests that abnormalities in airway smooth muscle functions, induced by variety of extracellular stimuli, may play an important role in the development of airway hyperresponsiveness. Studies using isolated bronchial preparations or cultured cells show that inflammatory mediators and cytokines may alter calcium homeostasis in airway smooth muscle and render the cells nonspecifically hyperreactive to agonists. 相似文献
9.
10.
Sylvie Durant Josiane Coulaud Abdelaziz Amrani Abdelkader El Hasnaoui Mireille Dardenne Franoise Homo-Delarche 《Journal of autoimmunity》1993,6(6)
The effects of long-term chronic stress (induced by repeated restraint, overcrowding or both), short-term chronic stress (induced by a triad of stressors over a short period of time early in life) and adrenalectomy were investigated on the prevalence, on the degree of insulitis and various physiological and immunological parameters in the NOD mouse, a spontaneous model of type I-insulin-dependent diabetes mellitus (IDDM). Long-term chronic stress, obtained by restraint once a week or overcrowding, significantly protected NOD females, while both applied concomitantly had only a tendency to protect against diabetes. In contrast, short-term chronic stress had no significant effect on diabetes expression, whereas adrenalectomy resulted in a trend toward accelerated diabetes onset. The various long-term chronic stress paradigms exerted different effects on the progression of insulitis: repeated restraint tended to protect against insulitis, overcrowding had no effect but, when associated with restraint, significantly counteracted the beneficial effect of restraint alone. Adrenalectomy and short-term chronic stress had no significant effect on the development of insulitis. Various parameters, such as body, thymus and spleen weights, thymus and spleen cellularities, mitogen-induced spleen cell proliferation and serum corticosterone levels were also studied under the various experimental conditions. Taken together, the observations suggest that stressors modulate the expression of spontaneous autoimmune diabetes by exerting pleiotropic effects on immune and/or inflammatory components at the pancreas level and on peripheral glucose metabolism. 相似文献