全文获取类型
收费全文 | 1124582篇 |
免费 | 76356篇 |
国内免费 | 1429篇 |
专业分类
耳鼻咽喉 | 15813篇 |
儿科学 | 35968篇 |
妇产科学 | 29769篇 |
基础医学 | 160976篇 |
口腔科学 | 31487篇 |
临床医学 | 99944篇 |
内科学 | 212851篇 |
皮肤病学 | 25667篇 |
神经病学 | 86907篇 |
特种医学 | 45621篇 |
外国民族医学 | 201篇 |
外科学 | 170486篇 |
综合类 | 21872篇 |
现状与发展 | 1篇 |
一般理论 | 294篇 |
预防医学 | 77745篇 |
眼科学 | 25578篇 |
药学 | 89474篇 |
7篇 | |
中国医学 | 2844篇 |
肿瘤学 | 68862篇 |
出版年
2021年 | 8237篇 |
2019年 | 8531篇 |
2018年 | 12595篇 |
2017年 | 10017篇 |
2016年 | 11473篇 |
2015年 | 12444篇 |
2014年 | 16666篇 |
2013年 | 24547篇 |
2012年 | 33541篇 |
2011年 | 35754篇 |
2010年 | 20770篇 |
2009年 | 19072篇 |
2008年 | 33142篇 |
2007年 | 35456篇 |
2006年 | 35784篇 |
2005年 | 33985篇 |
2004年 | 32549篇 |
2003年 | 31402篇 |
2002年 | 30281篇 |
2001年 | 61802篇 |
2000年 | 63647篇 |
1999年 | 52125篇 |
1998年 | 12868篇 |
1997年 | 11388篇 |
1996年 | 11291篇 |
1995年 | 10550篇 |
1994年 | 9571篇 |
1993年 | 9092篇 |
1992年 | 38001篇 |
1991年 | 36451篇 |
1990年 | 35903篇 |
1989年 | 34516篇 |
1988年 | 31034篇 |
1987年 | 30151篇 |
1986年 | 28395篇 |
1985年 | 26666篇 |
1984年 | 19456篇 |
1983年 | 16318篇 |
1982年 | 9026篇 |
1979年 | 17219篇 |
1978年 | 11544篇 |
1977年 | 10379篇 |
1976年 | 9002篇 |
1975年 | 10211篇 |
1974年 | 11765篇 |
1973年 | 11403篇 |
1972年 | 10826篇 |
1971年 | 10163篇 |
1970年 | 9319篇 |
1969年 | 9006篇 |
排序方式: 共有10000条查询结果,搜索用时 265 毫秒
991.
HEAD CIRCUMFERENCE AND INTELLECTUAL PERFORMANCE OF PATIENTS WITH DUCHENNE MUSCULAR DYSTROPHY 总被引:3,自引:1,他引:2
R. E. Appleton K. Bushby D. Gardner-Medwin J. Welch P. J. Kelly 《Developmental medicine and child neurology》1991,33(10):884-890
The head circumferences of 64 patients with Duchenne muscular dystrophy were measured and found to be greater than those of a normal population. The patients had relative, and in 12 cases, absolute macrocephaly. 47 of the 64 patients underwent intelligence testing and were found to be significantly intellectually impaired, particularly in verbal and language skills. There was no correlation between head circumference or absolute macrocephaly and intellectual performance. The cause of macrocephaly in these patients is unknown and its relevance to the aetiology of intellectual impairment in Duchenne muscular dystrophy is not yet clear. 相似文献
992.
Myelinated fiber regeneration after crush injury is retarded in sciatic nerves of aging mice 总被引:2,自引:0,他引:2
To compare nerve regeneration in young adult and aging mice, the right sciatic nerves of 6- and 24-month-old mice were crushed at the sciatic notch. Two weeks later, both groups of mice were perfused with an aldehyde solution, and, after additional fixation, the sciatic nerves were processed so that the transverse sections of each nerve subsequently studied by light and electron microscopy included the entire posterior tibial fascicle 5 mm distal to the crush site. The same level was sectioned in unoperated contralateral nerves; these nerves served as controls. Electron micrographs and the Bioquant Image Analysis System IV were used to measure areas of posterior tibial fascicles and count the number of myelinated axons, the number of unmyelinated axons, and their frequency in Schwann cell units. In aging mice, the total number of regenerating myelinated axons was significantly reduced, but totals of regenerating unmyelinated axons in aging and young adults did not differ significantly. In aging mice, the frequency of Schwann cells that contained a single unmyelinated axon was greater, suggesting that before myelination began, Schwann cell ensheathment of axons also was slowed. After axotomy by a crush injury, the area of the posterior tibial fascicle was less than that in young adults and the distal disintegration of myelin sheath remnants also appeared to be retarded. The results indicate that responses of neurons, axons, and Schwann cells could be important in slowing the regeneration of myelinated fibers found in sciatic nerves from aging mice. 相似文献
993.
M K Shear G Ball M Fitzpatrick S Josephson J Klosko A Frances 《The Journal of nervous and mental disease》1991,179(8):468-472
This paper reports results of an open prospective study of 26 patients who met DSM-III criteria for panic disorder or agoraphobia with panic attacks. Cognitive-behavioral treatment alone produced clinically and statistically significant improvement in panic symptoms, including both full-blown and limited symptom episodes. In addition, the treatment produced improvement in associated symptoms of phobic avoidance and generalized anxiety. This work provides further preliminary indication of the usefulness of cognitive-behavioral strategies as an alternative to medication in symptom-oriented treatments. 相似文献
994.
995.
996.
A case of odontoameloblastoma affecting the left mandible is reported. Initially treated by conservative excision due to its small size, the lesion recurred after 18 months and was treated by radical excision and subsequent reconstruction by a rib graft. 相似文献
997.
998.
In this new radioimmunoassay system for determination of amatoxins in urine and plasma, a novel chemical approach is used for antigen and 125I-tracer production, based on a detoxified alpha-amanitin derivative (aldoamanitin). Total assay time, including data processing, is less than 100 min. The lowest detectable concentration is 1 microgram/L for urine, 0.1 microgram/L for plasma. In the clinically significant range, within-run CVs are less than 8%. This new 125I-based assay is a significant improvement over existing 3H technology in terms of speed, precision, and freedom from interference. 相似文献
999.
1000.
D J Brooks J S Gibbs P Sharp S Herold D R Turton S K Luthra E M Kohner S R Bloom T Jones 《Journal of cerebral blood flow and metabolism》1986,6(2):240-244
Regional cerebral [11C]3-O-methyl-D-glucose ([11C]MeG) uptake kinetics have been measured in five insulin-dependent diabetic patients and four normal controls using positron emission tomography (PET). Concomitant measurement of regional cerebral blood volume and CBF enabled corrections for the presence of intravascular [11C]MeG signal in cerebral regions of interest to be carried out, and regional cerebral [11C]MeG unidirectional extraction fractions to be computed. Four of the five diabetic subjects were studied with their fasting plasma glucose level clamped at a normoglycaemic level (4 mM), and four were studied at hyperglycaemic plasma glucose levels (mean 13 mM). The four diabetic subjects whose fasting plasma glucose levels were clamped at a normoglycaemic level of 4 mM had mean fasting whole-brain, cortical, and white matter [11C]MeG extraction fractions of 15, 15, and 16%, respectively, values similar to those found for the four normal controls (whole brain, 14%; cortex, 13%; white matter, 17%). Mean regional cerebral [11C]MeG extraction fractions were significantly reduced in diabetic subjects during hyperglycaemia whether their plasma insulin levels were undetectable or whether they were raised by continuous intravenous insulin infusion. Such a reduction in [11C]MeG extraction under hyperglycaemic conditions can be explained entirely in terms of increased competition between [11C]MeG and D-glucose for the passive facilitated transport carrier system for hexoses across the blood-brain barrier (BBB). It is concluded that the number and affinity of D-glucose carriers present in the BBB are within normal limits in treated insulin-dependent diabetic subjects. In addition, insulin appears to have no effect on the transport of D-glucose across the BBB. 相似文献