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排序方式: 共有772条查询结果,搜索用时 15 毫秒
101.
Stephens RW; Golder JP; Fayle DR; Hume DA; Hapel AJ; Allan W; Fordham CJ; Doe WF 《Blood》1985,66(2):333-337
Adherent monolayer cultures of human blood monocytes, peritoneal macrophages, bone marrow macrophages, and colonic mucosa macrophages were examined for their ability to produce and secrete minactivin, a specific inactivator of urokinase-type plasminogen activator. All except colonic mucosa macrophages produced and secreted appreciable amounts of minactivin, but only blood monocytes were stimulated by muramyl dipeptide (adjuvant peptide) to increase production. The minactivin from each of these populations could be shown to preferentially inhibit urokinase-type plasminogen activator and not trypsin, plasmin, or "tissue"-type plasminogen activator (HPA66). A plasminogen-activating enzyme present in monocyte cultures appeared unaffected by the presence of minactivin and could be shown to be regulated independently by dexamethasone. 相似文献
102.
Pieter?CJ?ter BorgEmail author Durk?Fekkes Jan?Maarten?Vrolijk Henk?R?van Buuren 《BMC gastroenterology》2005,5(1):11
Background
In primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) fatigue is a major clinical problem. Abnormal amino acid (AA) patterns have been implicated in the development of fatigue in several non-hepatological conditions but for PBC and PSC no data are available. This study aimed to identify abnormalities in AA patterns and to define their relation with fatigue. 相似文献103.
de Boer CJ; Schuuring E; Dreef E; Peters G; Bartek J; Kluin PM; van Krieken JH 《Blood》1995,86(7):2715-2723
Mantle cell lymphoma (MCL) is a clinicopathologic entity that is difficult to diagnose on histopathologic criteria. Approximately 50% to 70% of MCL contain a t(11;14)(q13;q32) translocation involving the cyclin D1 gene. Irrespective of this rearrangement, almost all MCL show overexpression of the cyclin D1 gene at the mRNA level. Other B-cell non-Hodgkin's lymphomas (NHL) do not show this rearrangement or overexpression of cyclin D1. We developed an immunohistochemical assay to detect overexpression of the cyclin D1 protein on conventional formalin-fixed, paraffin-embedded biopsies using the well-defined monoclonal antibody DCS-6. Expression in tumor cells was compared with expression of cyclin D1 in endothelial cells and fibroblasts. An exclusively nuclear staining pattern was observed. Moreover, expression was directly compared with the expression observed by immunoblot analysis with the same antibody, as well as with mRNA expression and with the occurrence of genomic rearrangements within the BCL-1 locus. Of 13 MCL that were analyzed by immunohistochemistry and immunoblot, 12 showed overexpression with both techniques, whereas no overexpression was observed in 39 other NHL. Of 13 additional MCL studied either by immunohistochemistry or immunoblot, 11 also showed overexpression. Two lymphomas morphologically indistinguishable from MCL but with an aberrant immunophenotype (CD5 negative, CD10 positive) both lacked overexpression of cyclin D1. These results underscore the significance of overexpression of the cyclin D1 protein as a specific marker for MCL. Detection of cyclin D1 overexpression on formalin-fixed, paraffin- embedded tissues using the DCS-6 monoclonal antibody can be applied for routine diagnostic purposes. 相似文献
104.
The fibrinolytic characteristics of the endothelial hybrid cell line EA.hy 926, established by fusing a human umbilical vein endothelial cell with a human carcinoma cell line, were studied. The hybrid cell line produced large amounts of tissue-type plasminogen activator (t- PA), plasminogen activator inhibitor type 1, and a small amount of urokinase. All plasminogen activator present in conditioned medium was complexed with inhibitor because the cells secreted plasminogen activator inhibitor in excess over plasminogen activator and no activator activity was detectable in conditioned media by direct activity assays. t-PA activator activity was, however, demonstrable in conditioned media after treatment with sodium dodecyl sulfate, in agreement with t-PA antigen determinations. Increased plasminogen activator inhibitor activity could be induced by incubating the cells in the presence of endotoxin or microtubule inhibitors, whereas increased t-PA activity could be induced by microtubule inhibitors. Interleukin-1 had no effect. The fibrinolytic characteristics of the hybrid cell line were stable for at least 30 passages. The perpetual human hybrid cell line EA.hy 926 therefore may be a useful tool for the study of fibrinolysis in cultured endothelial cells. 相似文献
105.
106.
LR Caplan C-S Chung RJ Wityk TA Glass J Tapia L Pazdera H-M Chang JF Dashe CJ Chaves K Vemmos M Leary LD Dewitt MS Pessin 《JOURNAL OF CLINICAL NEUROLOGY》2005,1(1):14-30
Among 407 New England Medical Center Posterior Circulation Registry (NEMC-PCR) patients, 59% had strokes without transient ischemic attacks (TIAs), 24% had TIAs before strokes, and 16% had only posterior circulation TIAs. Embolism was the commonest stroke mechanism accounting for 40% of cases (24% cardiac origin, 14% arterial origin, 2% had potential cardiac and arterial sources). In 32%, large artery occlusive lesions caused hemodynamic brain infarction. Stroke mechanisms in the posterior and anterior circulation are very similar. Infarcts most often included the distal posterior circulation territory (rostral brainstem, superior cerebellum and occipital and temporal lobes), while the proximal (medulla and posterior inferior cerebellum) and middle (pons and anterior inferior cerebellum) territories were equally involved. Infarcts that included the distal territory were twice as common as those that included the proximal or middle territories. Most distal territory infarcts were attributable to embolism. Thirty day mortality was low (3.6%). Embolic stroke mechanism, distal territory location, and basilar artery occlusive disease conveyed the worst prognosis. 相似文献
107.
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110.
De Klein A; Riegman PH; Bijlsma EK; Heldoorn A; Muijtjens M; den Bakker MA; Avezaat CJ; Zwarthoff EC 《Human molecular genetics》1998,7(3):393-398
We describe a G-->A transition within intron 5 of the NF2 gene. This
mutation creates a consensus splice branch point sequence. To our knowledge
this is the first report of a mutation that creates a functional branch
point sequence in a human hereditary disorder. The new branch point
sequence is located 18 bp upstream of a consensus splice acceptor site. A
consensus splice donor site is found 106 bp 3' of the acceptor site. Asa
consequence the G-->A transition results in an alternatively spliced
mRNA containing an additional exon 5a of 106 bp derived from intron
sequences. We cloned the mutant cDNA and show that due to an in-frame stop
codon the cDNA codes for a truncated NF2 protein. The mutation was observed
in three affected members of an NF2 family. In a tumour of one of the
family members both alternatively spliced and wild-type mRNA were found,
although the wild-type allele of the gene is absent due to an interstitial
deletion on chromosome 22. We also show that immunoprecipitations reveal
the presence of full-length wild-type NF2 protein in the tumour lysate.
These data support the hypothesis that some degree of normal splicing of
the mutant precursor RNA is taking place. It is therefore likely that this
residual activity of the mutant allele explains the relatively mild
phenotype in the family. These data also indicate that complete
inactivation of the gene is not required for tumour formation.
相似文献