全文获取类型
收费全文 | 7008篇 |
免费 | 856篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 33篇 |
儿科学 | 186篇 |
妇产科学 | 112篇 |
基础医学 | 922篇 |
口腔科学 | 173篇 |
临床医学 | 669篇 |
内科学 | 1610篇 |
皮肤病学 | 71篇 |
神经病学 | 495篇 |
特种医学 | 762篇 |
外科学 | 985篇 |
综合类 | 151篇 |
一般理论 | 2篇 |
预防医学 | 696篇 |
眼科学 | 58篇 |
药学 | 551篇 |
1篇 | |
中国医学 | 2篇 |
肿瘤学 | 398篇 |
出版年
2021年 | 94篇 |
2020年 | 49篇 |
2019年 | 80篇 |
2018年 | 105篇 |
2017年 | 94篇 |
2016年 | 109篇 |
2015年 | 99篇 |
2014年 | 159篇 |
2013年 | 204篇 |
2012年 | 262篇 |
2011年 | 312篇 |
2010年 | 200篇 |
2009年 | 194篇 |
2008年 | 241篇 |
2007年 | 280篇 |
2006年 | 295篇 |
2005年 | 264篇 |
2004年 | 265篇 |
2003年 | 241篇 |
2002年 | 244篇 |
2001年 | 204篇 |
2000年 | 224篇 |
1999年 | 190篇 |
1998年 | 160篇 |
1997年 | 137篇 |
1996年 | 136篇 |
1995年 | 129篇 |
1994年 | 91篇 |
1993年 | 111篇 |
1992年 | 125篇 |
1991年 | 124篇 |
1990年 | 133篇 |
1989年 | 174篇 |
1988年 | 149篇 |
1987年 | 164篇 |
1986年 | 171篇 |
1985年 | 171篇 |
1984年 | 140篇 |
1983年 | 111篇 |
1982年 | 85篇 |
1981年 | 98篇 |
1980年 | 82篇 |
1979年 | 82篇 |
1978年 | 63篇 |
1977年 | 76篇 |
1976年 | 57篇 |
1975年 | 57篇 |
1974年 | 54篇 |
1972年 | 62篇 |
1970年 | 53篇 |
排序方式: 共有7877条查询结果,搜索用时 0 毫秒
61.
62.
Apoptotic cell death in mouse models of GM2 gangliosidosis and observations on human Tay-Sachs and Sandhoff diseases 总被引:5,自引:2,他引:5
Huang JQ; Trasler JM; Igdoura S; Michaud J; Hanal N; Gravel RA 《Human molecular genetics》1997,6(11):1879-1885
Tay-Sachs and Sandhoff diseases are autosomal recessive neurodegenerative
diseases resulting from the inability to catabolize GM2 ganglioside by
beta-hexosaminidase A (Hex A) due to mutations of the alpha subunit
(Tay-Sachs disease) or beta subunit (Sandhoff disease) of Hex A. Hex B
(beta beta homodimer) is also defective in Sandhoff disease. We previously
developed mouse models of both diseases and showed that Hexa-/- (Tay-Sachs)
mice remain asymptomatic to at least 1 year of age while Hexb-/- (Sandhoff)
mice succumb to a profound neurodegenerative disease by 4-6 months of age.
Here we find that neuron death in Hexb-/- mice is associated with apoptosis
occurring throughout the CNS, while Hexa-/- mice were minimally involved at
the same age. Studies of autopsy samples of brain and spinal cord from
human Tay-Sachs and Sandhoff diseases revealed apoptosis in both instances,
in keeping with the severe expression of both diseases. We suggest that
neuron death is caused by unscheduled apoptosis, implicating accumulated
GM2 ganglioside or a derivative in triggering of the apoptotic cascade.
相似文献
63.
64.
Functional consequences of ROMK mutants linked to antenatal Bartter's syndrome and implications for treatment 总被引:4,自引:0,他引:4
The antenatal variant of Bartter's syndrome is an autosomal recessive
kidney disease characterized by polyhydramnios, premature delivery,
hypokalemic alkalosis and hypercalciuria. It is genetically heterogeneous,
having been linked recently to mutations in an ATP- sensitive, renal outer
medullary K+channel, ROMK, and earlier to mutations in the Na-K-2Cl
co-transporter, NKCC2. We characterized four of the mutations reported in
three heterozygous ROMK variants of antenatal Bartter's and found that each
expressed a distinct phenotype in Sf9 cells. One mutation expressed normal
function and appears to be an allelic polymorphism. The other three
mutations produced channels with significantly reduced K+fluxes. However,
the mechanisms in each case were different and reflected abnormalities in
phosphorylation, proteolytic processing or protein trafficking. The
different mechanisms may be important in the design of appropriate therapy
for patients with this disease.
相似文献
65.
Prof. I. M. L. Donaldson R. A. Dixon 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1980,38(3):245-255
Summary In cats, anaesthetized with chloralose and paralysed, the responses of units in the right lateral thalamus were recorded while the extrinsic ocular muscles (EOM) of the right eye were stretched in the dark. Phasic responses were found in all layers of the dorsal lateral geniculate nucleus (LGNd) and in the perigeniculate nucleus (PGN). A given unit usually responded to stretch of more than one EOM and thus to more than one direction of rotation of the eye in the orbit.
LGNd. Of a sample of 76 units in LGNd, 55 (72%) gave visual but no muscle responses and 21 (28%) responded to EOM stretch. In all, 40 units with EOM responses were examined and 25 of the 27 tested (93%) also had visual responses. Of the 40 units, 32 could be allocated to layers, thus: layer A, 8 (25%); layer A1, 20 (63%); layer B, 3 (9%); central interlaminar nucleus, 1 (3%). It is interesting that most of the EOM responses were found in layer A1 which receives the excitatory visual input from the eye whose EOM were stretched. Muscle responsive units occurred with ON- and OFF-centre visual responses of sustained and transient types.
PGN. In PGN, 21 units gave EOM responses and most of them were also excited by visual input.The conclusion is that the LGNd and PGN recieve an extraretinal proprioceptive signal which should be present during at least large saccadic eye movements. The anatomical pathways which may be involved and the significance of the signal are discussed briefly. 相似文献
66.
67.
Mutation of the gene encoding the enamel-specific protein, enamelin, causes autosomal-dominant amelogenesis imperfecta 总被引:6,自引:0,他引:6
Amelogenesis imperfecta (AI) is a group of inherited defects of dental enamel formation that shows both clinical and genetic heterogeneity. To date, mutations in the gene encoding amelogenin have been shown to underlie a subset of the X-linked recessive forms of AI. Although none of the genes underlying autosomal-dominant or autosomal-recessive AI have been identified, a locus for a local hypoplastic form has been mapped to human chromosome 4q11-q21. In the current investigation, we have analysed a family with an autosomal-dominant, smooth hypoplastic form of AI. Our results have shown that a splicing mutation in the splice donor site of intron 7 of the gene encoding the enamel-specific protein enamelin underlies the phenotype observed in this family. This is the first autosomal-dominant form of AI for which the genetic mutation has been identified. As this type of AI is clinically distinct from that localized previously to chromosome 4q11-q21, these findings highlight the need for a molecular classification of this group of disorders. 相似文献
68.
69.
70.
Dixon J Ellis I Bottani A Temple K Dixon MJ 《American journal of medical genetics. Part A》2004,(3):244-248
Treacher Collins syndrome (TCS) is an autosomal dominant disorder of facial development, which results from mutations in TCOF1. TCS comprises conductive hearing loss, hypoplasia of the mandible and maxilla, downward sloping palpebral fissures and cleft palate. Although, there is usually a reasonable degree of bilateral symmetry, a high degree of both inter- and intrafamilial variability is characteristic of TCS. The wide variation in the clinical presentation of different patients, together with the fact that more than 60% of cases arise de novo, can complicate the diagnosis of mild cases and genetic counselling. In the current study, we describe how molecular techniques have been used to facilitate pre- and postnatal disease diagnoses in 13 TCS families. 相似文献