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81.
Reiners J van Wijk E Märker T Zimmermann U Jürgens K te Brinke H Overlack N Roepman R Knipper M Kremer H Wolfrum U 《Human molecular genetics》2005,14(24):3933-3943
Usher syndrome (USH) is the most frequent cause of combined deaf-blindness in man. USH is clinically and genetically heterogeneous with at least 11 chromosomal loci assigned to the three USH types (USH1A-G, USH2A-C, USH3A). Although the different USH types exhibit almost the same phenotype in human, the identified USH genes encode for proteins which belong to very different protein classes and families. We and others recently reported that the scaffold protein harmonin (USH1C-gene product) integrates all identified USH1 molecules in a USH1-protein network. Here, we investigated the relationship between the USH2 molecules and this USH1-protein network. We show a molecular interaction between the scaffold protein harmonin (USH1C) and the USH2A protein, VLGR1 (USH2C) and the candidate for USH2B, NBC3. We pinpoint these interactions to interactions between the PDZ1 domain of harmonin and the PDZ-binding motifs at the C-termini of the USH2 proteins and NBC3. We demonstrate that USH2A, VLGR1 and NBC3 are co-expressed with the USH1-protein harmonin in the synaptic terminals of both retinal photoreceptors and inner ear hair cells. In hair cells, these USH proteins are also localized in the signal uptaking stereocilia. Our data indicate that the USH2 proteins and NBC3 are further partners in the supramolecular USH-protein network in the retina and inner ear which shed new light on the function of USH2 proteins and the entire USH-protein network. These findings provide first evidence for a molecular linkage between the pathophysiology in USH1 and USH2. The organization of USH molecules in a mutual 'interactome' related to the disease can explain the common phenotype in USH. 相似文献
82.
Janine M Prince Teresa C M Klinowska Emma Marshman Emma T Lowe Ulrike Mayer Jeff Miner Daniel Aberdam Dietmar Vestweber Barry Gusterson Charles H Streuli 《Developmental dynamics》2002,223(4):497-516
Epithelial cell survival is dependent on extracellular signals provided by both soluble factors and by adhesion. In the mammary gland, extensive apoptosis of epithelial cells occurs rapidly when lactation ceases, but the mechanism of apoptosis induction is not known. In tissue culture, mammary epithelial cells require laminin as a survival ligand and specific beta1 integrins are necessary to suppress apoptosis. To explore the possibility that dynamic changes in cell-matrix interactions contribute to the onset of apoptosis during mammary involution in vivo, a detailed immunohistochemical analysis of the expression of integrin subunits and their extracellular matrix ligands during mouse mammary gland development has been performed. The kinetics of apoptosis were determined by using tissue samples obtained from virgin, pregnant, lactating, and involuting gland. The maximal elevation of apoptosis occurred within 24 hr of weaning as determined by histologic analysis and caspase-3 staining. A wide variety of laminin subunits, together with nidogen-1 and -2, and perlecan were identified within the basement membrane region of epithelial ducts, lobules, and alveoli in both human and mouse mammary gland. However, no change in the distribution of any of the basement membrane proteins or their cognate integrin receptors was observed during the transition from lactation to apoptosis. Instead, we discovered that altered ligand-binding conformation of the beta1 integrin to a nonbinding state coincided with the immediate onset of mammary apoptosis. This finding may provide a novel dynamic mechanism for inhibiting the transduction of extracellular matrix survival signals, thereby contributing to the onset of apoptosis in a developmental context in vivo. 相似文献
83.
Preventive Effects of Escherichia coli Strain Nissle 1917 on Acute and Chronic Intestinal Inflammation in Two Different Murine Models of Colitis 下载免费PDF全文
Michael Schultz Ulrike G. Strauch Hans-J?rg Linde Sonja Watzl Florian Obermeier Claudia G?ttl Nadja Dunger Nicole Grunwald Jürgen Sch?lmerich Heiko C. Rath 《Clinical and Vaccine Immunology : CVI》2004,11(2):372-378
Escherichia coli strain Nissle 1917 (EcN) is as effective in maintaining remission in ulcerative colitis as is treatment with mesalazine. This study aims to evaluate murine models of acute and chronic intestinal inflammation to study the antiinflammatory effect of EcN in vivo. Acute colitis was induced in mice with 2% dextran-sodium sulfate (DSS) in drinking water. EcN was administered from day −2 to day +7. Chronic colitis was induced by transfer of CD4+ CD62L+ T lymphocytes from BALB/c mice in SCID mice. EcN was administered three times/week from week 1 to week 8 after cell transfer. Mesenteric lymph node (MLN) cytokine secretion (of gamma interferon [IFN-γ], interleukin 5 [IL-5], IL-6, and IL-10) was measured by enzyme-linked immunosorbent assay. Histologic sections of the colon were analyzed by using a score system ranging from 0 to 4. Intestinal contents and homogenized MLN were cultured, and the number of E. coli-like colonies was determined. EcN was identified by repetitive extragenic palindromic (REP) PCR. EcN administration to DSS-treated mice reduced the secretion of proinflammatory cytokines (IFN-γ, 32,477 ± 6,377 versus 9,734 ± 1,717 [P = 0.004]; IL-6, 231 ± 35 versus 121 ± 17 [P = 0.02]) but had no effect on the mucosal inflammation. In the chronic experimental colitis of the transfer model, EcN ameliorated the intestinal inflammation (histology score, 2.7 ± 0.2 versus 1.9 ± 0.3 [P = 0.02]) and reduced the secretion of proinflammatory cytokines. Translocation of EcN and resident E. coli into MLN was observed in the chronic colitis model but not in healthy controls. Administration of EcN ameliorated acute and chronic experimental colitis by modifying proinflammatory cytokine secretion but had no influence on the acute DSS-induced colitis. In this model, preexisting colitis was necessary for translocation of EcN and resident E. coli into MLN. 相似文献
84.
Retrograde transport of horseradish peroxidase injected iontophoretically into the nucleus of the optic tract of cats revealed that the direction-selective cells in this pretectal nucleus receive direct retinal projections from small retinal ganglion cells, the so-called gamma-cells. These cells from a horizontal band on the contralateral retina. Few labeled cells are found in the ipsilateral temporal retina. The input from the contralateral retina is 10 times more numerous than from the ipsilateral one. In both retinae the highest concentration of labeled cells is near the area centralis. 相似文献
85.
Lena Möbus Elke Rodriguez Inken Harder Agatha Schwarz Ulrike Wehkamp Dora Stölzl Nicole Boraczynski Sascha Gerdes Thomas Litman Andreas Kleinheinz Susanne Abraham Annice Heratizadeh Christiane Handrick Eva Haufe Jochen Schmitt Thomas Werfel Stephan Weidinger 《The Journal of allergy and clinical immunology》2021,147(5):1959-1965.e2
86.
Myxobolus cotti (Myxozoa: Myxosporea) is described as found in the central nervous system of the bullhead (Cottus gobio) caught in the Alpine lake Königssee and in a brook in the Bavarian Forest, Federal Republic of Germany (El-Matbouli and Hoffmann 1987). Aggregations of spores and polysporoblastic trophozoites compressed and replaced large areas of the white and grey matter of the brain and spinal cord. These aggregations may be surrounded by a thin, connective tissue capsule; in a few cases they were associated with loose infiltrates of glial cells. Neither conspicuous tissue reactions nor inflammatory responses were evident. No other organs were seen to be infected withM. cotti. Mature spores are oval, with a tapering anterior end, and the pyriform polar capsules are nearly equal in size. Fresh spores measured 8.9–15.1 m in length (mean, 12.4 m) and 8–12.4 m in width (mean, 9.6 m); polar capsules were 4.3–9 m long (mean, 6.4 m); and 2–3.8 m wide (mean, 2.9 m). Light microscopy, the ultrastructure of pansporoblasts, sporogenesis and mature spores are described. 相似文献
87.
Morphological detection and quantification of lipoprotein(a) deposition in atheromatous lesions of human aorta and coronary arteries 总被引:8,自引:0,他引:8
Axel Niendorf Matthias Rath Katrin Wolf Susanne Peters Hartmut Arps Ulrike Beisiegel Manfred Dietel 《Virchows Archiv : an international journal of pathology》1990,417(2):105-111
Summary Lipoprotein(a), as an atherogenic particle, represents an independent risk factor for coronary heart disease. In the present
study the morphological distribution of apoprotein (a) and apoprotein B within the arterial wall is described. Apoprotein
B, a constituent of very low-density lipoprotein, low-density lipoprotein and lipoprotein(a) has previously been demonstrated
in atheromatous lesions. Lipoprotein(a) possesses an additional protein, designated apoprotein (a). Autopsy material (n=74) from the left coronary artery and from the thoracic aorta has been examined by means of immunohistochemistry and both
apoprotein (a) and apoprotein B were detected, primarily associated with the extracellular matrix and accumulating in lesions
in the arterial wall. The staining pattern for both antigens was almost always found to be congruent, suggesting that the
detection of (a)-antigen has to be attributed at least in part to the presence of lipoprotein(a). It is concluded that both
low-density lipoprotein and lipoprotein(a) have an important role in the pathogenesis of atherosclerosis. 相似文献
88.
Ulrike Horstmann Bernd Arnold Günter J. Hmmerling 《European journal of immunology》1986,16(7):863-865
We and others have previously reported that homologous exchange of alpha 1 or alpha 2 domains between different alleles led to loss of most determinants recognized by cytotoxic T lymphocytes (CTL) raised against the parental H-2 class I antigens. Here we demonstrate that exchange of alpha 1 or alpha 2 domains between the Kk and Kd allele results in the formation of neodeterminants against which allospecific CTL can be generated in responder mice of various related and unrelated H-2 haplotypes. In fact, only CTL against the neodeterminants on the hybrid molecules were found and none against the parental Kk and Kd determinants. In addition our data show that recognition of the neodeterminants is H-2 unrestricted. These findings suggest that in the hybrid molecules the basic structure of a major histocompatibility complex molecule has been preserved although most parental allodeterminants on the alpha 1 and alpha 2 domains have been modified. 相似文献
89.
The ultrastructure of acute silicosis 总被引:2,自引:0,他引:2
90.
Ulrike Fuhrmann Karsten Parczyk Michael Klotzbücher Helmut Klocker A. C. B. Cato 《Journal of molecular medicine (Berlin, Germany)》1998,76(7):512-524
Antihormones are by definition antagonists of steroid hormone action. They interact with the ligand binding domains of steroid
hormone receptors and competitively inhibit the action of the receptors by mechanisms that are not quite understood. In certain
cases antihormones also exhibit agonistic activity especially in connection with certain naturally occurring receptor mutants.
These observations together with findings of indiscriminate interaction of antihormones with several classes of steroid receptors
have necessitated a search of more effective and reliable antihormones. Recent advances in the resolution of the crystal structure
of the ligand binding domains of certain members of the steroid receptor family and identification of non-liganded activation
of steroid receptors have produced considerable information that can be harnessed into a fruitful search for a new generation
of antihormones.
Received: 19 June 1997 / Accepted: 10 October 1997 相似文献