全文获取类型
收费全文 | 2717014篇 |
免费 | 232620篇 |
国内免费 | 12768篇 |
专业分类
耳鼻咽喉 | 37354篇 |
儿科学 | 85907篇 |
妇产科学 | 68626篇 |
基础医学 | 451993篇 |
口腔科学 | 71674篇 |
临床医学 | 241634篇 |
内科学 | 461868篇 |
皮肤病学 | 78756篇 |
神经病学 | 236990篇 |
特种医学 | 107059篇 |
外国民族医学 | 68篇 |
外科学 | 430230篇 |
综合类 | 86980篇 |
现状与发展 | 23篇 |
一般理论 | 2123篇 |
预防医学 | 230756篇 |
眼科学 | 61124篇 |
药学 | 181249篇 |
22篇 | |
中国医学 | 8319篇 |
肿瘤学 | 119647篇 |
出版年
2022年 | 22696篇 |
2021年 | 54367篇 |
2020年 | 34682篇 |
2019年 | 57568篇 |
2018年 | 69503篇 |
2017年 | 52807篇 |
2016年 | 58157篇 |
2015年 | 72780篇 |
2014年 | 106849篇 |
2013年 | 171833篇 |
2012年 | 71762篇 |
2011年 | 68760篇 |
2010年 | 111171篇 |
2009年 | 117108篇 |
2008年 | 56240篇 |
2007年 | 56695篇 |
2006年 | 68359篇 |
2005年 | 64094篇 |
2004年 | 66527篇 |
2003年 | 57896篇 |
2002年 | 47891篇 |
2001年 | 64023篇 |
2000年 | 55400篇 |
1999年 | 63426篇 |
1998年 | 60764篇 |
1997年 | 59739篇 |
1996年 | 57392篇 |
1995年 | 52920篇 |
1994年 | 47144篇 |
1993年 | 44159篇 |
1992年 | 41459篇 |
1991年 | 39323篇 |
1990年 | 36651篇 |
1989年 | 36956篇 |
1988年 | 34384篇 |
1987年 | 33460篇 |
1986年 | 31896篇 |
1985年 | 33077篇 |
1984年 | 34366篇 |
1983年 | 32750篇 |
1982年 | 36800篇 |
1981年 | 35120篇 |
1980年 | 33184篇 |
1979年 | 26633篇 |
1978年 | 26771篇 |
1977年 | 25378篇 |
1976年 | 23053篇 |
1975年 | 21002篇 |
1974年 | 20010篇 |
1973年 | 19295篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
The annual conferences of the European Public Health Associationare a good opportunity to look around in the old continent.I vividly remember the Dresden conference in 2002, which broughtthe European public health community to a city reflecting thegreat and tragic history of Germany. Some of that history, andits effects on German public health, can be experienced firsthand 相似文献
993.
994.
995.
The authors suggest additional criteria evidencing inflammations in the gallbladder and colloid stability of the bile: bile acid absorption and cholesterol sedimentation coefficients. Derivation of these coefficients is based on biochemical examination of the bile with measurements of bile acid, cholesterol, and bilirubin concentrations in both portions. The results of examinations of 99 subjects evidence the diagnostic value and specificity of the characteristics, and availability of this method for clinical practice. 相似文献
996.
Peter D. Le Roux David S. Jardine Paul M. Kanev John D. Loeser 《Child's nervous system》1991,7(1):34-39
We reviewed the results of all pediatric patients undergoing intracranial pressure (ICP) monitoring in a 2-year period at our institution. The outcome of patients suffering hypoxia or ischemic injuries (HII) is compared to those suffering non-hypoxic or non-ischemic injuries (NHII). Thirty-four patients had ICP monitors placed during the study period. Inconplete patient information led to the exclusion of 5 patients. An additional 5 patients were excluded because no measures to control ICP were taken after the monitor was placed. Twenty-four patients required treatment for raised ICP (hyperventilation, 24; mannitol, 19; barbiturate coma, 6). Admission Glasgow Coma Score in patients suffering HII (median score 5) and NHII (median score 6) were not significantly different (Mann-Whitney U Test). Only 2 of 8 patients with HII were near-drowning vietims. The remaining 6 had HII from other causes (5 survivors of various forms of asphyxia and 1 of cardiac arrest). All 8 patients had poor outcomes (1 severely disabled; 7 died). The 16 patients with NHII had a variety of diagnoses (6 trauma, 5 encephalitis, 4 bacterial meningitis, 1 diabetic ketoacidosis). Among these, 6 had good outcomes and 10 poor outcomes (2 severely disabled, 2 vegetative, and 6 died). The difference in outcome between patients with NHII and HII is significant at P=0.059 (Fischer Exact test). Patients with NHII may benefit from ICP monitoring. Patients with HII from near-drowning and other causes did not appear to benefit from ICP monitoring and interventions directed at controlling ICP. 相似文献
997.
Iver A. Langmoen Tryggve Lundar Ingebjørg Storm-Mathisen Sverre O. Lie Karl H. Hovind 《Child's nervous system》1991,7(1):13-15
We present 36 consecutive patients with intrinsic glioma of the pons. Tumors with exophytic expansion were excluded. There were 16 females and 20 males, ranging in age from 2 to 13 years, median 6 years. The most common presenting symptoms were cranial nerve dysfunction. unsteadiness of gait, and hemiparesis. Computed tomography (CT) showed a hypodense (17/21) or isodense (4/21) expansion of the pons. Five tumors had areas of contrast enhancement. Following information about prognosis and possible types of management, parents decided for or against radiation therapy: twentyfour children underwent irradiation and 12 did not. Median survival among children receiving a full course of irradiation was 280 days, compared to 140 days in an equivalent group of non-irradiated children. Hemiparesis presenting without cranial nerve symptoms and contrast enhancement on CT scan were poor prognostic factors, whereas sex, age, and duration of symptoms at diagnosis were unrelated to prognosis. 相似文献
998.
Extracellular 5-HT in the anterior hypothalamus/preoptic area (AH/POA) and caudate nucleus of the freely moving cat was measured using in vivo brain microdialysis. Administration of 8-OH-DPAT, a 5-HT1A receptor agonist that decreases 5-HT neuronal activity, decreased extracellular 5-HT in both brain areas. Extracellular 5-HT levels were also examined in relationship to the sleep-wake cycle, because previous data from our laboratory have indicated that behavioral state is the primary determinant of 5-HT neuronal discharge. As with 5-HT neuronal discharge, extracellular 5-HT was increased during active behavioral states and decreased during somnolent periods. These first two sets of findings confirm the ability of the microdialysis technique to measure physiological fluctuations in extracellular 5-HT levels and support the hypothesis that neuronal discharge is a major determinant of extracellular 5-HT levels. Levels of the 5-HT metabolite 5-hydroxyindole acetic acid (5-HIAA) in the AH/POA were also responsive to changes in behavioral state and administration of 8-OH-DPAT, though fluctuations in extracellular 5-HIAA were less robust and temporally delayed. Finally, extracellular 5-HT and 5-HIAA were examined in the AH/POA during fever induced by systemic injection of the synthetic pyrogen muramyl dipeptide. Previous data from our laboratory have indicated that 5-HT neuronal activity is unaffected by this manipulation, though 5-HT has been implicated specifically in thermoregulation. Pyrogen-induced hypothermia produced no specific change in 5-HT efflux, because any changes noted could be accounted for by behavioral state changes. These data are consistent with the hypothesis that the brain serotonergic system is closely linked to the sleep-wake-arousal cycle. However, extracellular 5-HT may be involved in thermoregulatory processes as part of a global role in modulating neuronal activity in coordination with the behavioral state of the animal. 相似文献
999.
1000.
K. Dorovini-Zis A. P. Zis 《Journal of neural transmission (Vienna, Austria : 1996)》1991,84(1-2):75-84
Summary Autonomic innervation of the adrenal cortex has been demonstrated in several species. Detailed ultrastructural studies on the innervation of the zona fasciculata of the normal human adrenal cortex are lacking. We report herein our observations on the pattern of innervation of the cells of the zona fasciculata of the normal adult human cortex at both the light and electron microscope levels. Postganglionic unmyelinated fibers were observed to descend from a dense capsular meshwork and to be distributed as delicate branches among the columns of endocrine cells. Immunoperoxidase staining confirmed the presence of nerve fibers in the zona fasciculata in a distribution similar to that observed after staining with silver impregnation methods. Ultrastructural findings lent further support to these observations by the demonstration of bundles of unmyelinated fibers with focal enlargements containing terminal boutons with both clear and dense core vesicles in close approximation with the endocrine cells. 相似文献