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91.
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Pridmore RD Berger B Desiere F Vilanova D Barretto C Pittet AC Zwahlen MC Rouvet M Altermann E Barrangou R Mollet B Mercenier A Klaenhammer T Arigoni F Schell MA 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(8):2512-2517
Lactobacillus johnsonii NCC 533 is a member of the acidophilus group of intestinal lactobacilli that has been extensively studied for their "probiotic" activities that include, pathogen inhibition, epithelial cell attachment, and immunomodulation. To gain insight into its physiology and identify genes potentially involved in interactions with the host, we sequenced and analyzed the 1.99-Mb genome of L. johnsonii NCC 533. Strikingly, the organism completely lacked genes encoding biosynthetic pathways for amino acids, purine nucleotides, and most cofactors. In apparent compensation, a remarkable number of uncommon and often duplicated amino acid permeases, peptidases, and phosphotransferase-type transporters were discovered, suggesting a strong dependency of NCC 533 on the host or other intestinal microbes to provide simple monomeric nutrients. Genome analysis also predicted an abundance (>12) of large and unusual cell-surface proteins, including fimbrial subunits, which may be involved in adhesion to glycoproteins or other components of mucin, a characteristic expected to affect persistence in the gastrointestinal tract (GIT). Three bile salt hydrolases and two bile acid transporters, proteins apparently critical for GIT survival, were also detected. In silico genome comparisons with the >95% complete genome sequence of the closely related Lactobacillus gasseri revealed extensive synteny punctuated by clear-cut insertions or deletions of single genes or operons. Many of these regions of difference appear to encode metabolic or structural components that could affect the organisms competitiveness or interactions with the GIT ecosystem. 相似文献
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Evaluation of specific value of endoscopic biopsies and brush cytology for malignancies of the oesophagus and stomach. 下载免费PDF全文
The value of multiple biopsies and brush cytology at oesophago-gastroscopy was assessed in relation to macroscopy and localization on 100 verified tumours in a prospective study. The cumulative accuracy achieved was 96%. This was significantly better (P less than 0-01) than that of biopsy (83%) and of cytology (85%). While the reliability of both procedures was not significantly different in malignancies of the oesophagus, the gastric body, and the antrum, cytoloty was significantly more accurate in cancers of the cardia (90% and 55% respectively, P less than 0-05). Cytology was also more reliable in stenosing tumours (92%/72%,P less than 0-05). In polypoid malignancies a positive but not significant trend was found in favour of multiple biopsies (94%/64%). One of the two early cancers was only diagnosed by cytology. The results confirm the high diagnostic accuracy of multiple endoscopic biopsies combined with brush cytology and demonstrate the value of cytology in stenosing tumours, especially in those of the cardia. 相似文献
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Sandra P Toelle David Wille Bernhard Schmitt Ianina Scheer Beat Thöny Barbara Plecko 《Epileptic Disord》2014,16(1):88-92
Loss‐of‐function mutations in the FOLR1 gene (MIM *136430), encoding the folate receptor alpha, impair cerebral folate transport and lead to a progressive neurometabolic disorder. We report on a 5‐year‐old boy with progressive ataxia, from the age of 2 years and 6 months, with myoclonic jerks, regression, and impressive myoclonic tonic spasms with drop attacks, which were partially provoked by touching his face or washing his hands. Delayed myelination and cerebellar atrophy on cranial MRI were important clues to the diagnosis of cerebral folate transport deficiency, which was confirmed by homozygosity for the known nonsense mutation p.R204X in the FOLR1 gene. Computed tomography taken after head injury revealed bilateral calcifications in the basal ganglia as a novel finding in a patient with FOLR1 mutation. [Published with video sequences] 相似文献
98.
Andrea Superti-Furga Antonio Rossi Beat Steinmann Richard Gitzelmann 《American journal of medical genetics. Part A》1996,63(1):144-147
Achondrogenesis type 1B (ACG-1B), atelosteogenesis type 2 (AO-2), and diastrophic dysplasia (DTD) are recessively inherited chondrodysplasias of decreasing severity caused by mutations in the diastrophic dysplasia sulfate transporter (DTDST) gene on chromosome 5. In these conditions, sulfate transport across the cell membrane is impaired which results in insufficient sulfation of cartilage proteoglycans and thus in an abnormally low sulfate content of cartilage. The severity of the phenotype correlates well with the predicted effect of the underlying DTDST mutations: homozygosity or compound heterozygosity for stop codons or transmembrane domain substitutions mostly result in achondrogenesis type 1B, while other structural or regulatory mutations usually result in one of the less severe phenotypes. The chondrodysplasias arising at the DTDST locus constitute a bone dysplasia family with recessive inheritance. © 1996 Wiley-Liss, Inc. 相似文献
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100.
Luis F. Santamaria Babi Bernhard Moser Maria Teresa Perez Soler Ren Moser Pius Loetscher Beat Villiger Kurt Blaser Conrad Hauser 《European journal of immunology》1996,26(9):2056-2061
We studied the involvement of chemokines that bind to G protein-coupled receptors in the migration of skin homing T cells across a bilayer vascular construct (BVC) consisting of a fibroblast matrix underneath an activated endothelial (EC) monolayer. Based on the expression of the cutaneous lymphocyte-associated antigen (CLA), a skin homing receptor, CD45R0+ T cells freshly isolated from blood or HUT-78 cutaneous T lymphoma cells were separated into CLA+ and CLA− subpopulations. These T cells were incubated on interleukin (IL)-1β and tumor necrosis factor-α-activated EC, and the number of transmigrated cells was determined. The chemokine IL-8 was selectively involved in the enhanced migration of CLA+ T cells across activated EC as demonstrated by blocking antibody to IL-8 but not to GRO-α, MCP-1 and RANTES. Identical results were obtained with both human umbilical vein EC (HUVEC) and microvascular skin EC (HDMEC). Pertussis toxin selectively inhibited the enhanced transendothelial migration (TEM) of CLA+ T cells, suggesting that CLA-dependent TEM depends on Gi protein-transmitted signals. Moreover, the IL-8 receptor B (IL-8RB) appeared to be functionally involved in TEM, as demonstrated by receptor desensitization with the CXC chemokines IL-8 and GRO-α and by blocking the IL-8RB with specific monoclonal antibodies. Although only the IL-8RB was involved in CLA-dependent TEM, mRNA encoding IL-8RA and IL-8RB was expressed by both CLA+ and CLA− T cells. This correlated with IL-8RA and IL-8RB surface expression on these cells. Thus, the IL-8RB is selectively functional in TEM of T cells expressing the skin homing receptor CLA. Our results demonstrate a critical role for IL-8 and possibly other IL-8RB ligands in addition to the IL-8RB in TEM and suggest the involvement of these molecules in the homing of specific T cells to inflamed skin. 相似文献