全文获取类型
收费全文 | 1537919篇 |
免费 | 115499篇 |
国内免费 | 17843篇 |
专业分类
耳鼻咽喉 | 21511篇 |
儿科学 | 42260篇 |
妇产科学 | 41377篇 |
基础医学 | 211717篇 |
口腔科学 | 43193篇 |
临床医学 | 141836篇 |
内科学 | 291389篇 |
皮肤病学 | 32187篇 |
神经病学 | 117749篇 |
特种医学 | 61447篇 |
外国民族医学 | 573篇 |
外科学 | 227883篇 |
综合类 | 65472篇 |
现状与发展 | 61篇 |
一般理论 | 454篇 |
预防医学 | 104114篇 |
眼科学 | 37705篇 |
药学 | 121618篇 |
192篇 | |
中国医学 | 15211篇 |
肿瘤学 | 93312篇 |
出版年
2021年 | 18512篇 |
2020年 | 13385篇 |
2019年 | 15296篇 |
2018年 | 19461篇 |
2017年 | 16411篇 |
2016年 | 16962篇 |
2015年 | 21817篇 |
2014年 | 28823篇 |
2013年 | 35524篇 |
2012年 | 48414篇 |
2011年 | 52187篇 |
2010年 | 30893篇 |
2009年 | 28109篇 |
2008年 | 44204篇 |
2007年 | 47236篇 |
2006年 | 47999篇 |
2005年 | 46914篇 |
2004年 | 41709篇 |
2003年 | 40350篇 |
2002年 | 38803篇 |
2001年 | 67654篇 |
2000年 | 69864篇 |
1999年 | 60445篇 |
1998年 | 17944篇 |
1997年 | 16781篇 |
1996年 | 15648篇 |
1995年 | 14745篇 |
1994年 | 13543篇 |
1992年 | 44390篇 |
1991年 | 42656篇 |
1990年 | 41631篇 |
1989年 | 40437篇 |
1988年 | 37784篇 |
1987年 | 37062篇 |
1986年 | 35467篇 |
1985年 | 33533篇 |
1984年 | 25079篇 |
1983年 | 21233篇 |
1979年 | 24024篇 |
1978年 | 17103篇 |
1977年 | 14872篇 |
1976年 | 13401篇 |
1975年 | 15276篇 |
1974年 | 18081篇 |
1973年 | 17560篇 |
1972年 | 16823篇 |
1971年 | 15717篇 |
1970年 | 14891篇 |
1969年 | 14338篇 |
1968年 | 13451篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
971.
H Ogura H Kubota I Nomura T Tomoda K Araki Y Ogura T Kurashige 《The Japanese journal of antibiotics》1989,42(2):401-410
A new macrolide antibiotic, clarithromycin (TE-031, A-56268), was studied for its clinical efficacy in the field of pediatrics. Patients treated were infants and children ranging from 2 months to 11 years old suffering from acute bronchitis in 5 cases, acute tonsillitis in 2 cases, Mycoplasma pneumonia in 2 cases, pertussis in 6 cases, scarlatina in 1 case and acute enteritis in 2 cases, a total of 18 cases. TE-031 was administered 19.7-43.5 mg/kg in daily doses and lengths of treatment ranged from 4 to 19 days. As regards to its clinical efficacy, good or excellent results were obtained in all cases: excellent in 11 cases and good in 7 cases. No clinical side effects nor abnormal laboratory test values obviously attributable to TE-031 were observed. 相似文献
972.
H H Metzler W Stenzl P H Rehak K H Tscheliessnigg W F List 《The Journal of thoracic and cardiovascular surgery》1987,93(6):823-831
Hemodynamic changes after isolated impairment of right ventricular function (produced by increasing afterload by temporary banding of the pulmonary artery) were studied in 22 ventilated pigs during increased levels of positive end-expiratory pressure (4, 8, 12, and 16 cm H2O). In the open chest group, application of positive end-expiratory pressure produced only a slight decrease of cardiac index. After right ventricular damage a decrease of cardiac index of more than 25% occurred only when higher levels of positive end-expiratory pressure were applied. In contrast to the open chest group, the closed chest group showed more distinct cardiovascular responses after positive end-expiratory pressure. In the damaged right ventricle with a positive end-expiratory pressure of 16 cm H2O, right ventricular end-diastolic pressure increased more than 100%. With positive end-expiratory pressure, cardiac index decreased 34% before and 47% after right ventricular damage. We conclude that positive end-expiratory pressure induces a more pronounced decrease in cardiac index if right ventricular function is impaired. During open chest conditions with lower levels of positive end-expiratory pressure, these changes are only small, however, and probably irrelevant. During closed chest conditions, the hemodynamic changes are much more pronounced. High right ventricular end-diastolic pressures resulting from impaired right ventricular contractility as well as from high levels of positive end-expiratory pressure may have an impact on biventricular function and right ventricular coronary driving pressure. 相似文献
973.
Effects of N-(2,6-dimethylphenyl)-2-(2-oxo-1-pyrrolidinyl)acetamide (DM-9384) on learning and memory in rats 总被引:1,自引:0,他引:1
Effects of N-(2,6-dimethylphenyl)-2-(2-oxo-1-pyrrolidinyl) acetamide (DM-9384) on learning and memory were studied using four different experimental rat models. In electroconvulsive shock- or scopolamine-induced amnesia in the step-through passive avoidance task, DM-9384 improved both types of amnesia when administered before the training trial. Aniracetam also showed similar but somewhat weaker effects. Furthermore, in the scopolamine amnesia model, an improvement was confirmed with arecoline. The dose-response curves for these compounds were bell-shaped. In the shuttle box active avoidance task, DM-9384 administered daily 1 hr before each training session facilitated the acquisition process of the avoidance response. In addition, the experiment of light-dark discrimination task with positive reinforcement showed that this compound administered daily after each session slightly accelerated the acquisition process of the correct response. These results suggest an ability of DM-9384 to enhance cognitive functions. 相似文献
974.
F R Ochsendorf H Sch?fer R Milbradt 《Der Hautarzt; Zeitschrift für Dermatologie, Venerologie, und verwandte Gebiete》1987,38(7):400-403
In an 80-year-old woman with pemphigus erythematosus, we demonstrated ANA as well as anti-DNA antibodies in the serum. This finding supports the argument that this skin disorder represents a combination of a disease of the pemphigus group with systemic lupus erythematosus. 相似文献
975.
McArdle's disease with myoadenylate deaminase deficiency: observations in a combined enzyme deficiency 总被引:1,自引:0,他引:1
Exercise and work potential of a patient with coexistent myophosphorylase and myoadenylate deaminase (AMPDA) deficiency was compared with that of three patients with myophosphorylase deficiency alone. The patient with the combined defect failed to produce an abnormal rise in serum ammonia or hypoxanthine as seen in the other patients after forearm exercise. Maximum oxygen consumption and work rates during cycle ergometer testing were similar in all patients, but well below controls. The occurrence of two defects involving short-term energy metabolism in muscle presents an opportunity to define further the metabolic role of AMPDA. 相似文献
976.
977.
978.
979.
980.
Hypomagnesemia due to isolated renal magnesium loss was demonstrated in two unrelated families with autosomal dominant mode of inheritance. Magnesium infusions performed in two patients showed not only a reduced renal magnesium threshold but also a lowered renal tubular maximum for magnesium. All members of both families who presented with hypomagnesemia had also a lowered excretion of calcium in the urine, presumably as a consequence of increased reabsorption in Henle's loop. 相似文献