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31.
Recently genotyping of JC virus (JCV) DNA in renal tissue was reported to be useful to identify the geographic origin of unidentified cadavers. In the above study, autopsied tissue samples without storage or stored in a frozen state were used. This study examined JCV DNA sequence modifications caused by formalin-fixation, in an attempt to elucidate whether formalin-fixed, paraffin-embedded tissue samples can also be used to determine the genotypes of JCV DNA in the kidney. In four cases, a 610 bp typing region of the JCV genome was PCR-amplified from renal tissues stored for 1 year in three different states: frozen at -80 degrees C [Amaker, B.H., Chandler, F.W., Huey, L.O., Colwell, R.M., 1997. Molecular detection of JC virus in embalmed, formalin-fixed, paraffin-embedded brain tissue. J. Forensic Sci., 1157-1159], formalin-fixed, paraffin-embedded [Ault, G.S., Stoner, G.L., 1992. Two major types of JC virus defined in progressive multifocal leukoencephalopathy brain by early and late coding region DNA sequences. J. Gen. Virol. 73, 2669-2678], and soaked in 5% formalin [Baksh, F.K., Finkelstein, S.D., Swalskey, P.A., Stoner, G.L., Ryschkewitsch, C.F., Randhawa, P.R., 2001. Molecular genotyping of BK and JC virus in human polyomavirus-associated interstitial nephritis after renal transplantation. Am. J. Kidney Dis. 38 (2), 354-365]. The amplified fragments were cloned, and the resultant clones were sequenced. In frozen samples, single sequences ('original' sequences) were detected in all cases. In formalin-fixed, paraffin-embedded samples, not only the original sequences but also those with 1-6 base substitutions were detected. From formalin-soaked samples, the original sequences and those with 1-5 and 10-13 substitutions were detected. The genotyping of JCV DNA was not hampered by the presence of 1-6 substitutions, but a shift in JCV genotypes was observed in sequences with 10-13 substitutions. Thus, it was concluded that the genotypes of JCV DNA in the kidney can be determined only with specimens stored in a frozen state or formalin-fixed for a short time.  相似文献   
32.
BACKGROUND: Our aim is to evaluate the significance of DLST by Shosaikoto. METHODS: We clinically evaluated 3 cases of drug-induced pneumonia assumed to be caused by Shosaikoto, and we performed DLST of Shosaikoto for healthy controls, and compared the data with drug-induced pneumonia cases of Shosaikoto. RESULTS: As clinical characteristics of 3 cases, 2 cases were positive for hepatitis C virus antibody, and 1 case was positive for DLST of Shosaikoto. The observed chest high-resolution CT (HRCT) findings showed hypersensitivity pneumonia (HP) pattern in all 3 cases. Prognosis was good in all 3 cases. DLST of Shosaikoto was positive in 27.5% of healthy controls. Stimulation index (S.I.) of DLST in drug-induced pneumonia cases increased depending on drug dilution density, compared to that of healthy controls. CONCLUSION: DLST of Shosaikoto showed high false-positive rate. However, we may be able to distinguish the true-positive cases with the false-positive cases by comparing the S.I. of DLST according to drug dilution density.  相似文献   
33.
Severe inflammatory responses after major surgeries, trauma, and infection develop multiple organ dysfunction. In the mechanisms of the pathogenesis of these responses, activated neutrophils are thought to be important in terms of their ability to produce various kinds of proteinases, which can degrade various proteins constructing human tissues. Among their proteinases, neutrophil elastase is the strongest serine proteinase secreted from activated neutrophils. Thus, we examined in this study the inhibitory effect and therapeutic efficacy of newly produced recombinant human Kunitz-type proteinase inhibitor (R-020), which coded the second domain of human urinary trypsin inhibitor. R-020 was effective in significantly improving the survival rate after induction of the rat lethal peritonitis model (cecal ligation and punctureinduced septic shock model). We suggest that various serine proteinases are implicated in the pathogenesis of neutrophil-related multiple organ failure and that recombinant human Kunitz-type proteinase inhibitor might be effective in the treatment of these kinds of organ dysfunction.  相似文献   
34.
Despite the importance of short-chain fatty acids (SCFA) in maintaining the ruminant physiology, the mechanism of SCFA absorption is still not fully studied. The goal of this study was to elucidate the possible involvement of monocarboxylate transporter 1 (MCT1) in the mechanism of SCFA transport in the caprine rumen, and to delineate the precise cellular localization and the level of MCT1 protein along the entire caprine gastrointestinal tract. RT-PCR revealed the presence of mRNA encoding for MCT1 in all regions of the caprine gastrointestinal tract. Quantitative Western blot analysis showed that the level of MCT1 protein was in the order of rumen ≥ reticulum > omasum > caecum > proximal colon > distal colon > abomasum > small intestine. Immunohistochemistry and immunofluorescence confocal analyses revealed widespread immunoreactive positivities for MCT1 in the caprine stomach and large intestine. Amongst the stratified squamous epithelial cells of the forestomach, MCT1 was predominantly expressed on the cell boundaries of the stratum basale and stratum spinosum. Double-immunofluorescence confocal laser-scanning microscopy confirmed the co-localization of MCT1 with its ancillary protein, CD147 in the caprine gastrointestinal tract. In vivo and in vitro functional studies, under the influence of the MCT1 inhibitors, p -chloromercuribenzoate (pCMB) and p -chloromercuribenzoic acid (pCMBA), demonstrated significant inhibitory effect on acetate and propionate transport in the rumen. This study provides evidence, for the first time in ruminants, that MCT1 has a direct role in the transepithelial transport and efflux of the SCFA across the stratum spinosum and stratum basale of the forestomach toward the blood side.  相似文献   
35.
We found a HhaI/BstUI polymorphism in the 3′ untranslated region of a novel gene which was localized to 11p15.5. This region is one of prominent imprinting domains and contains multiple imprinted genes, such as H19, IGF2 , KVLQT1, and p57 KIP2 , which suggests that regional factors might contribute to the imprinting. This polymorphism will be useful in the allelic analysis of expression and methylation of the novel gene. Received: July 24, 1998 / Accepted: July 29, 1998  相似文献   
36.
IL-1 is a pro-inflammatory cytokine consisted of two molecular species, IL-1alpha and IL-1beta, and the IL-1 receptor antagonist (IL-1Ra) is a natural inhibitor of both molecules. Although it is suggested that IL-1 potentiates immune responses mediated by T(h)2 cells, the role of IL-1 in asthma still remains unclear. In this study, we demonstrate that the ovalbumin (OVA)-induced airway hypersensitivity response (AHR) in IL-1alpha/beta-deficient (IL-1alpha/beta(-/-)) mice was significantly reduced from the levels seen in wild-type mice, whereas the responses seen in IL-1Ra(-/-) mice were profoundly exacerbated, suggesting that IL-1 is required for T(h)2 cell activation during AHR. OVA-specific T cell proliferation, IL-4 and IL-5 production by T cells, and IgG1 and IgE production by B cells in IL-1alpha/beta(-/-) mice were markedly reduced compared with these responses in wild-type mice; such responses were enhanced in IL-1Ra(-/-) mice. Using IL-1alpha(-/-) and IL-1beta(-/-) mice, we determined that both IL-1alpha and IL-1beta are involved in this reaction. Both IgG1 and IgE levels were reduced in IL-1beta(-/-) mice, while only IgE levels were affected in IL-1alpha(-/-) mice, indicating a functional difference between IL-1alpha and IL-1beta. These observations indicate that IL-1 plays important roles in the development of AHR.  相似文献   
37.
38.
Summary Addition of the protein phosphatase inhibitor, calyculin-A, to 3T3 fibroblasts causes a marked change in cell morphology. Initially the cells become rounded, develop surface blebs and then detach from the substratum. In the detached cells an unusual ball-like structure is observed. This study focuses on the cytoskeleton during these calyculin-A-induced morphological changes. Stress fibres disappear as the cells begin to round and aggregates of actin are formed towards the apical surface of the cell. These aggregates condense, in the detached cells, to form the ball structure of approximately 3 m diameter. Between the ball and the nucleus are cables of intermediate filaments that appear to be attached to the surface of the ball and to the nuclear lamina. Using a procedure designed for the isolation of nuclei the nucleus-ball complex can be obtained. Analysis of the nucleus-ball preparation by immunofluorescence and electron microscopy demonstrate that the ball contains actin and that intermediate filaments are located between the ball and the nucleus. In this preparation, the intermediate filaments also appear to attach to the surfaces of the ball and the nucleus. Electrophoretic analysis of the nucleus-ball preparation indicates that, in addition to actin, a major component of the ball is myosin. It is suggested that the formation of the ball is caused by an actin-myosin-based contractile process, initiated by the phosphorylation of myosin. The aggregation of the actomyosin draws together the intermediate filaments into the area between the ball and nucleus. This hypothesis requires that vimentin binds both to the nucleus and to some component of the ball.  相似文献   
39.
Human epidermal growth factor receptor (HER) family proteins are currently major targets of therapeutic monoclonal antibodies against various epithelial cancers. However, the resistance of cancer cells to HER family-targeted therapies, which may be caused by cancer heterogeneity and persistent HER phosphorylation, often reduces overall therapeutic effects. We herein showed that a newly discovered molecular complex between CD98 and HER2 affected HER function and cancer cell growth. The immunoprecipitation of the HER2 or HER3 protein from lysates of SKBR3 breast cancer (BrCa) cells revealed the HER2-CD98 or HER3-CD98 complex. The knockdown of CD98 by small interfering RNAs inhibited the phosphorylation of HER2 in SKBR3 cells. A bispecific antibody (BsAb) that recognized the HER2 and CD98 proteins was constructed from a humanized anti-HER2 (SER4) IgG and an anti-CD98 (HBJ127) single chain variable fragment, and this BsAb significantly inhibited the cell growth of SKBR3 cells. Prior to the inhibition of AKT phosphorylation, BsAb inhibited the phosphorylation of HER2, however, significant inhibition of HER2 phosphorylation was not observed in anti-HER2 pertuzumab, trastuzumab, SER4 or anti-CD98 HBJ127 in SKBR3 cells. The dual targeting of HER2 and CD98 has potential as a new therapeutic strategy for BrCa.  相似文献   
40.
We studied the brain uptake of amino acid in a patient with acute cerebral infarction with L-[2-(F-18)] fluorophenylalanine and positron emission tomography. The increased accumulation of the ligand was specifically found in the peri-infarct area where oxygen metabolism was still maintained but decreased later in the 72-day follow-up period. The kinetic analysis revealed that increased accumulation was not due to increased transport from the blood to the brain but to delayed washout from the brain to the blood. Although the mechanism is still unknown, abnormally high accumulation of L-[F-18]fluorophenylalanine may predict delayed neuronal changes after ischemic insults of the brain.  相似文献   
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