全文获取类型
收费全文 | 1881篇 |
免费 | 135篇 |
国内免费 | 27篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 20篇 |
妇产科学 | 8篇 |
基础医学 | 317篇 |
口腔科学 | 1篇 |
临床医学 | 55篇 |
内科学 | 69篇 |
神经病学 | 1280篇 |
特种医学 | 41篇 |
外科学 | 25篇 |
综合类 | 93篇 |
预防医学 | 16篇 |
眼科学 | 7篇 |
药学 | 75篇 |
中国医学 | 6篇 |
肿瘤学 | 24篇 |
出版年
2023年 | 11篇 |
2022年 | 3篇 |
2021年 | 37篇 |
2020年 | 38篇 |
2019年 | 34篇 |
2018年 | 33篇 |
2017年 | 39篇 |
2016年 | 35篇 |
2015年 | 52篇 |
2014年 | 63篇 |
2013年 | 74篇 |
2012年 | 57篇 |
2011年 | 70篇 |
2010年 | 79篇 |
2009年 | 86篇 |
2008年 | 90篇 |
2007年 | 78篇 |
2006年 | 84篇 |
2005年 | 75篇 |
2004年 | 83篇 |
2003年 | 72篇 |
2002年 | 62篇 |
2001年 | 46篇 |
2000年 | 29篇 |
1999年 | 32篇 |
1998年 | 40篇 |
1997年 | 18篇 |
1996年 | 25篇 |
1995年 | 31篇 |
1994年 | 32篇 |
1993年 | 27篇 |
1992年 | 29篇 |
1991年 | 26篇 |
1990年 | 26篇 |
1989年 | 32篇 |
1988年 | 21篇 |
1987年 | 19篇 |
1986年 | 40篇 |
1985年 | 68篇 |
1984年 | 42篇 |
1983年 | 46篇 |
1982年 | 44篇 |
1981年 | 48篇 |
1980年 | 48篇 |
1979年 | 5篇 |
1977年 | 2篇 |
1976年 | 5篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1969年 | 4篇 |
排序方式: 共有2043条查询结果,搜索用时 15 毫秒
1.
2.
Ruiqi Pang Xiaofan Wang Zhiqiang Du Feifei Pei Zhiyue Li Libing Sun Shuying Wang Yingnan Peng Xupeng Lu Xiaoqun Gao Cheng Chang 《Journal of anatomy》2020,236(2):370-377
Monocarboxylates cannot cross the blood-brain barrier freely to participate in brain energy metabolism. Specific monocarboxylate transporters (MCTs) are needed to cross cellular membranes. Monocarboxylate transporter 2 (MCT2) is a major monocarboxylate transporter encoded by the SLC16A7 gene. Recent studies reported that neurodegenerative diseases of the CNS, such as Alzheimer's disease (AD) and Parkinson's disease (PD), were related to energy metabolic impairment. MCT2 also plays an important role in energy metabolism in the CNS. To provide experimental evidence for future research on the role of MCT2 in the pathological process of CNS degenerative diseases, the distribution and density of MCT2 in different subregions of wild-type mouse brain was examined using immunohistochemistry, western blot and immunogold post-embedding electron microscopic techniques. The amount of MCT2 was higher in cerebellum than in cortex and hippocampus on western blots, and there was no statistical difference between cortex and hippocampus. Immunohistochemistry assay revealed the highest density of MCT2 in the CA3 of the hippocampus. The granular cell layer of the cerebellum contained more MCT2 than the molecular layer. The MCT2 density on the end feet of astrocytes of molecular layer was lower than in hippocampus, but the postsynaptic densities (PSDs) of asymmetric synapses in the molecular layer exhibited a high density using immunogold post-embedding electron microscopic techniques. 相似文献
3.
4.
Serge A. Mitelman Monte S. Buchsbaum Bradley T. Christian Brian M. Merrill Bradley R. Buchsbaum Jogeshwar Mukherjee 《The world journal of biological psychiatry》2020,21(5):368-382
AbstractObjectives: Overlapping decreases in extrastriatal dopamine D2/D3-receptor availability and glucose metabolism have been reported in subjects with schizophrenia. It remains unknown whether these findings are physiologically related or coincidental.Methods: To ascertain this, we used two consecutive 18F-fluorodeoxyglucose and 18F-fallypride positron emission tomography scans in 19 healthy and 25 unmedicated schizophrenia subjects. Matrices of correlations between 18F-fluorodeoxyglucose uptake and 18F-fallypride binding in voxels at the same xyz location and AFNI-generated regions of interest were evaluated in both diagnostic groups.Results: 18F-fluorodeoxyglucose uptake and 18F-fallypride binding potential were predominantly positively correlated across the striatal and extrastriatal grey matter in both healthy and schizophrenia subjects. In comparison to healthy subjects, significantly weaker correlations in subjects with schizophrenia were confirmed in the right cingulate gyrus and thalamus, including the mediodorsal, lateral dorsal, anterior, and midline nuclei. Schizophrenia subjects showed decreased D2/D3-receptor availability in the hypothalamus, mamillary bodies, thalamus and several thalamic nuclei, and increased glucose uptake in three lobules of the cerebellar vermis.Conclusions: Dopaminergic system may be involved in modulation of grey matter metabolism and neurometabolic coupling in both healthy human brain and psychopathology. Hyperdopaminergic state in untreated schizophrenia may at least partly account for the corresponding decreases in grey matter metabolism. 相似文献
5.
目的:测量颞骨岩部重要骨性结构,探讨小脑幕裂孔侧血管、神经位置的关系,为颞下经小脑幕入路提供解剖学基础.方法:在15例(30侧)颅骨标本上,以弓状隆起最高点为基点测量其与破裂孔外缘、面神经管裂孔、内耳孔后缘的距离.在10例(20侧)成人尸体头部行颞下经小脑幕入路,观测小脑幕裂孔侧方区域小脑上动脉、大脑后动脉、动眼神经、滑车神经、三叉神经以及小脑幕间的关系.结果:弓状隆起最高点距破裂孔外缘(34.98±1.67)mm,距面神经管裂孔(14.67±1.74)mm,距内耳孔后缘(15.31±1.78)mm;Labbe静脉入横窦处距STP(横窦、乙状窦、岩上窦交界)(24.60±5.82)mm;滑车神经入小脑幕游离缘处距后床突后外方(15.50±3.85)mm.结论:测量弓状隆起最高点与破裂孔外缘、面神经管裂孔、内耳孔后缘的距离及观测小脑幕裂孔侧区域小脑上动脉、大脑后动脉、动眼神经、滑车神经、三叉神经的走行有利于提高颞下经小脑幕手术入路的安全性和成功率. 相似文献
6.
7.
Nico Angliker Michael Burri Mariana Zaichuk Jean‐Marc Fritschy Markus A. Rüegg 《The European journal of neuroscience》2015,42(8):2595-2612
The mammalian target of rapamycin (mTOR) is a key regulator of cellular growth which associates with other proteins to form two multi‐protein complexes called mTORC1 and mTORC2. Dysregulation of mTORC1 signalling in brain is implicated in neuropathological conditions such as autism spectrum or neurodegenerative disorders. Accordingly, allosteric mTOR inhibitors are currently in clinical trials for the treatment of such disorders. Here, we ablated either mTORC1 or mTORC2 conditionally in Purkinje cells of the mouse cerebellum to dissect their role in the development, function and survival of these neurons. We find that the two mouse models largely differ from each other by phenotype and cellular responses. Inactivation of mTORC2, but not of mTORC1, led to motor coordination deficits at an early age. This phenotype correlated with developmental deficits in climbing fibre elimination and impaired dendritic self‐avoidance in mTORC2‐deficient Purkinje cells. In contrast, inactivation of mTORC1, but not of mTORC2, affected social interest of the mice and caused a progressive loss of Purkinje cells due to apoptosis. This cell loss was paralleled by age‐dependent motor deficits. Comparison of mTORC1‐deficient Purkinje cells with those deficient for the mTORC1 inhibitor TSC1 revealed a striking overlap in Purkinje cell degeneration and death, which included neurofilamentopathy and reactive gliosis. Altogether, our study reveals distinct roles of mTORC1 and mTORC2 in Purkinje cells for mouse behaviour and the survival of neurons. Our study also highlights a convergence between the phenotypes of Purkinje cells lacking mTORC1 activity and those expressing constitutively active mTORC1 due to TSC1 deficiency. 相似文献
8.
9.
郭永华 《临床超声医学杂志》2019,21(2)
目的:总结后颅窝正常和异常的胎儿小脑及小脑蚓部的矢状面的声像学特征,了解小脑细微结构的改变与胎儿畸形的关系。 相似文献
10.
Hirofumi Fujita Arata Oh‐Nishi Hiroko Ohki‐Hamazaki Izumi Sugihara 《The Journal of comparative neurology》2015,523(13):1886-1912
The avian cerebellum is organized into multiple longitudinal stripes defined by expression profiles of aldolase C (zebrin II) in Purkinje cells. The relationship between the aldolase C striped pattern and the olivocerebellar projection pattern is crucial in understanding cerebellar functional compartmentalization. We identified all aldolase C stripes across all lobules with the serial section alignment analysis method and then looked at this relationship by anterograde and retrograde labeling of olivocerebellar axons in the chick cerebellum. Aldolase C stripes were generally consistent and continuous from lobule I through VII and to the medial part of lobules VIII–IXb. The dorsal and ventral lamellas (DL, VL) of the inferior olive projected to the stripes in these areas with a simple mediolateral topographic relation. A few aldolase C stripes appeared at the lateral edge of lobules VI–VIII. Several more stripes were added in the lateral parts of lobules IXa–IXb and IXc–X. The medial column (MC) of the inferior olive projected to the stripes in lobules VIII–X, including the added lateral stripes, with a complex topographic relation. Sharp boundaries between aldolase C‐positive and ‐negative stripes often accompanied a gap in the Purkinje cell layer and bordered topographically distinct groups of axons. Although the compartmental organization of the chick cerebellum is comparable to that of the mammalian cerebellum, several significant differences in the organization suggest partly separate evolutionary lineages of the mammalian and avian cerebella. We propose that rostral lobules may be evolved by rostral extension of medial stripes from caudal lobules in the avian cerebellum. J. Comp. Neurol. 523:1886–1912, 2015 © 2015 Wiley Periodicals, Inc. 相似文献