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991.
L. J. Jennings G. M. Salido M. -J. Pozo J. S. Davison K. A. Sharkey R. W. Lea J. Singh 《Inflammation research》1995,44(10):447-453
We have investigated the effects of histamine on motility of the gallbladder and characterized the receptor types involved. Histamine and the histamine H1-receptor agonist, 2-thiazolylethylamine (2-TEA) contracted the isolated guinea-pig gallbladder strip in a dose dependent manner. The contractile response to histamine was shifted to the right by the H1-receptor antagonist, mepyramine. In pre-contracted gallbladder strips, the H2-receptor agonist dimaprit reduced the tension generated in a dose dependent fashion. The histamine H2-receptor antagonist, ranitidine shifted the histamine concentration effect curve to the left and attenuated the dose dependent relaxations elicited at high concentrations. The histamine H3-receptor agonist, (R)--methylhistamine (RMHA) elicited dose dependent contraction of the tissue which was significantly inhibited in the presence of mepyramine. The effects of electrical field stimulation (EFS) on the strips were not significantly altered by the presence of RMHA (10–10–10–7 M) indicating little pre-synaptic H3 activity in this tissue. Histamine immunoreactivity (IR) was detected in gallbladder whole mount preparations of the mucosa and the muscularis/serosa. The histamine IR appeared cell bound in cells of varying morphological characteristics but no IR was detected in nerve fibres or cell bodies (ganglia). Alcian blue staining was consistent with the distribution of histamine IR cells as mast cells. The results indicate that histamine is distributed in the guinea-pig gallbladder and it can regulate contractile activity via activation of H1 and H2 but not H3 receptors. 相似文献
992.
993.
A case of Klinefelter's Syndrome with a paracentric inversion in chromosome 12 is described. The karyotype was determined to be 47, XXY, inv(12)(q15q24) and the significance of the breakpoints on chromosome 12 is discussed. 相似文献
994.
Human immunodeficiency virus generates the accessory proteins Nef, viral infectivity factor (Vif), viral protein R, and viral
protein U or viral protein X during viral replication in host cells. Although the significance of these accessory proteins
is often lost in vitro, they are essential for viral pathogenesis in vivo. Therefore, these proteins have much potential as
antiviral targets. Recent data reveal Vif perturbs an ill-defined antiviral pathway in host cells allowing HIV replication.
These data highlight a common feature among HIV accessory proteins in manipulating the host to aid viral pathogenesis. Therefore,
these new insights into Vif and other HIV accessory proteins are reviewed, emphasizing host cell interactions and new targets
for therapeutic intervention. 相似文献
995.
Kamesh?R?Ayasolla Shailendra?Giri Avtar?K?Singh Inderjit?SinghEmail author 《Journal of neuroinflammation》2005,2(1):21
Background
Alzheimer's disease (AD) pathology shows characteristic 'plaques' rich in amyloid beta (Aβ) peptide deposits. Inflammatory process-related proteins such as pro-inflammatory cytokines have been detected in AD brain suggesting that an inflammatory immune reaction also plays a role in the pathogenesis of AD. Glial cells in culture respond to LPS and Aβ stimuli by upregulating the expression of cytokines TNF-α, IL-1β, and IL-6, and also the expression of proinflammatory genes iNOS and COX-2. We have earlier reported that LPS/Aβ stimulation-induced ceramide and ROS generation leads to iNOS expression and nitric oxide production in glial cells. The present study was undertaken to investigate the neuroprotective function of AICAR (a potent activator of AMP-activated protein kinase) in blocking the pro-oxidant/proinflammatory responses induced in primary glial cultures treated with LPS and Aβ peptide. 相似文献996.
997.
Timo D Müller Anke Hinney André Scherag Thuy T Nguyen Felix Schreiner Helmut Schäfer Johannes Hebebrand Christian L Roth Thomas Reinehr 《BMC medical genetics》2008,9(1):85
Background
We have previously identified strong association of six single nucleotide polymorphisms (SNPs) in FTO (fat mass and obesity associated gene) to early onset extreme obesity within the first genome wide association study (GWA) for this phenotype. The aim of this study was to investigate whether the obesity risk allele of one of these SNPs (rs9939609) is associated with weight loss in a lifestyle intervention program. Additionally, we tested for association of rs9939609 alleles with fasting blood parameters indicative of glucose and lipid metabolism. 相似文献998.
Yeni YN Hou FJ Ciarelli T Vashishth D Fyhrie DP 《Annals of biomedical engineering》2003,31(6):726-732
Linear microcracks and diffuse damage (staining over a broad region) are two types of microscopic damage known to occur in vivo in human vertebral trabecular bone. These damage types might be associated with vertebral failure. Using microcomputed tomography and finite element analysis for specimens of cancellous bone, we estimated the stresses in the trabeculae of human vertebral tissue for inferosuperior loading. Microdamage was quantified histologically. The density of in vivo linear microcracks was, but the diffuse damage area was not, related to the estimates of von Mises stress distribution in the tissue. In vivo linear microcrack density increased with increasing coefficient of variation of the trabecular von Mises stress and with increasing average trabecular von Mises stress generated per superoinferior apparent axial stress. Nonlinear increase in linear crack density, similar to the increase of the coefficient of variation of trabecular shear stresses, with decreasing bone stiffness and bone volume fraction suggests that damage may accumulate rather rapidly in diseases associated with low bone density due to the dramatic increase of shear stresses in the tissue. © 2003 Biomedical Engineering Society.
PAC2003: 8719Rr, 8719Xx, 8759Ls, 8759Fm, 8710+e 相似文献
999.
Knut Hagen Lars J Stovner Frank Skorpen Elin Pettersen John-Anker Zwart 《BMC medical genetics》2007,8(1):34
Background
The catechol-O-methyltransferase (COMT) gene contains a functional polymorphism, Val158Met which has been related to common diseases like cancer, psychiatric illness and myocardial infarction. Whether the Val158Met polymorphism is associated with survival has not been evaluated in the general population. The aim of this prospective study was to evaluate the impact of codon 158 COMT gene polymorphism on survival in a population-based cohort. 相似文献1000.