全文获取类型
收费全文 | 188633篇 |
免费 | 1719篇 |
国内免费 | 149篇 |
专业分类
耳鼻咽喉 | 1214篇 |
儿科学 | 6921篇 |
妇产科学 | 3205篇 |
基础医学 | 17991篇 |
口腔科学 | 1899篇 |
临床医学 | 13482篇 |
内科学 | 35073篇 |
皮肤病学 | 829篇 |
神经病学 | 17743篇 |
特种医学 | 9443篇 |
外科学 | 30684篇 |
综合类 | 2331篇 |
预防医学 | 18472篇 |
眼科学 | 2848篇 |
药学 | 10011篇 |
中国医学 | 632篇 |
肿瘤学 | 17723篇 |
出版年
2023年 | 126篇 |
2022年 | 214篇 |
2021年 | 410篇 |
2020年 | 285篇 |
2019年 | 355篇 |
2018年 | 22226篇 |
2017年 | 17619篇 |
2016年 | 19838篇 |
2015年 | 1296篇 |
2014年 | 1353篇 |
2013年 | 1511篇 |
2012年 | 7989篇 |
2011年 | 22041篇 |
2010年 | 19374篇 |
2009年 | 12109篇 |
2008年 | 20399篇 |
2007年 | 22645篇 |
2006年 | 1474篇 |
2005年 | 3063篇 |
2004年 | 4263篇 |
2003年 | 5053篇 |
2002年 | 3124篇 |
2001年 | 345篇 |
2000年 | 462篇 |
1999年 | 246篇 |
1998年 | 308篇 |
1997年 | 315篇 |
1996年 | 171篇 |
1995年 | 177篇 |
1994年 | 151篇 |
1993年 | 128篇 |
1992年 | 82篇 |
1991年 | 136篇 |
1990年 | 159篇 |
1989年 | 95篇 |
1988年 | 74篇 |
1987年 | 63篇 |
1986年 | 55篇 |
1985年 | 49篇 |
1984年 | 47篇 |
1983年 | 43篇 |
1982年 | 41篇 |
1980年 | 53篇 |
1969年 | 26篇 |
1968年 | 24篇 |
1938年 | 60篇 |
1937年 | 25篇 |
1934年 | 30篇 |
1932年 | 56篇 |
1930年 | 46篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
131.
132.
Najat MA Farsi 《BMC oral health》2007,7(1):15
Background
This study aimed to investigate the signs of oral dryness in relation to different salivary variables and to correlate subjective complaints of oral dryness with salivary flow rate. 相似文献133.
D. Le Elizabeth Eric R. Powers Jian-Ping Bin Howard Leong-Poi N. Craig Goodman Sanjiv Kaul 《Journal of nuclear cardiology》2007,14(2):207-214
Background The mechanism by which transmyocardial revascularization (TMR) offers clinical benefit is controversial. We hypothesized that
TMR ameliorates ischemia by reversing paradoxical catecholamine-induced vasoconstriction.
Methods and Results Chronic ischemic cardiomyopathy was created in 11 dogs by placing ameroid constrictors on the proximal coronary arteries and
their major branches. Six weeks later, 35 channels were created percutaneously in the left circumflex artery region, with
the left anterior descending artery region serving as control. At rest, wall thickening and myocardial blood flow did not
change in the treated region, whereas they deteriorated in the control bed. Contractile and myocardial blood flow reserve
increased in the treated region but deteriorated in the control region. There was diminished iodine 123 metaiodobenzylguanidine
uptake and a significant reduction in noradrenergic nerves in the treated region compared with the control region, with a
corresponding reduction in tissue tyrosine hydroxylase activity.
Conclusions We conclude that the absence of a catecholamine-induced reduction in MBF reserve and contractile reserve in the TMR-treated
region with associated evidence of neuronal injury indicates that the relief of exercise-induced ischemia after TMR most likely
results from reversal of paradoxical catecholamine-induced vasoconstriction. These findings may have implications in selecting
patients who would benefit from TMR.
Supported in part by grants from the National Institutes of Health (R01-HL66034 and K-08-HL074290-01). Bethesda. Md. The radio-labeled
microspheres were provided by DuPont Pharmaceuticals, North Billerica. Mass, and the ultrasound equipment was supplied by
Philips. Andover, Mass. Dr Leong-Poi was the recipient of a Fellowship Training Grant from the Canadian Institute of Health
Research and the Heart and Stroke Foundation of Canada. 相似文献
134.
Introduction Hypothalamic hamartomas are congenital malformations. Clinically, they can be asymptomatic, but they cause seizures, mental
retardation and precocious puberty in many cases.
Case report A 20-day-old boy with hypothalamic hamartoma and bilateral anophthalmia was presented. Except those, no other congenital anomaly
was detected.
Conclusion This is a rare case of hypothalamic hamartoma with bilateral anophthalmia. The mutations at SOX2 has an important role in
the developing brain and eyes. 相似文献
135.
Introduction Suprasellar arachnoid cysts are uncommon developmental anomalies that are most often diagnosed in childhood. Because the natural history and pathogenesis of these remain poorly defined, optimal treatment guidelines are not yet established.Case report We report a case of spontaneous disappearance of a suprasellar arachnoid cyst that persisted after a ventriculoperitoneal shunt performed 10 years earlier. A 5-year-old boy presented with impaired visual acuity and urinary incontinence. Magnetic resonance (MR) imaging showed a large suprasellar cyst with noncommunicating hydrocephalus. A ventriculoperitoneal shunt was put in place to alleviate current aggravation of hydrocephalus symptoms. Because of the persistent size of the cyst and signs of brainstem compression on a repeat computed tomography (CT), we recommended surgical exploration and decompression. However, the boy’s parents declined any further surgical treatment, and the patient was subsequently lost to follow-up for 10 years. When the patient returned to our clinic at the age of 15 years, a repeat MR scan showed a complete disappearance of the cyst. His family denied any significant interval history.Discussion This case represents only the third reported case of spontaneous disappearance of a suprasellar arachnoid cyst. We discuss possible mechanisms and clinical characteristics of the disappearance of the arachnoid cyst with review of the literature. 相似文献
136.
137.
138.
139.
140.