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31.
BACKGROUND: Mizolastine is a nonsedating H1 histamine receptor antagonist with additional antiallergic properties currently marketed in Europe for the treatment of seasonal and perennial allergic rhinitis (PAR) and urticaria. OBJECTIVE: This multicenter, randomized, double-blind, parallel-group study was conducted to evaluate the efficacy and safety of mizolastine in PAR compared with loratadine and placebo. METHODS: After a 1-week placebo run-in period, 428 adult PAR patients received placebo (146 of 428), mizolastine 10 mg (141 of 428), or loratadine 10 mg (141 of 428) once daily for 28 days. Symptoms were evaluated by patients and physicians using a total nasal score, evaluating itching, rhinorrhea, nasal blockade, and sneezing severity. RESULTS: Mizolastine treatment resulted in a significantly greater decrease in patient-rated total nasal score than placebo after 2 weeks (D14; -42%, P < 0.001) and at the end of the treatment period (-46%, P = 0.01), and significantly greater than that observed with loratadine at D14 (P = 0.031). No significant difference in change in total nasal score was observed between loratadine and placebo at 2- and 4-week visits. The global safety was satisfactory and the incidence of adverse events was similar in the three treatment groups. CONCLUSIONS: Mizolastine provides effective symptom relief in PAR together with a satisfactory safety profile. Improvement with mizolastine was significantly greater than placebo throughout the study despite a large placebo effect. Also mizolastine's effects were greater those observed with loratadine after 2 weeks of treatment.  相似文献   
32.
We have used a set of single-chain variable fragment antibodies (sc) genetically fused with an influenza hemagglutinin-derived peptide as a means to investigate the role of CR1 and CR2 in antigen presentation by B cells. When incubated with the B cell lymphoma 2PK3, peptide-containing sc specific for either CR1 or CR1/2 mediated activation of the hemagglutinin peptide-specific T cell line IP-12-7, as assessed by IL-2 production. Efficient presentation was dependent on the binding of the constructs to CR1/2, implying that receptor-mediated endocytosis is responsible for the effect. Cross-linkage of CR1/2 or CD19 by mAb did not increase the extent of T cell activation. However, when CR1/2 was co-ligated with the BCR--using either polyclonal goat anti-mouse IgG or recombinant protein LA--the antigen concentration required to activate T cells decreased by two orders of magnitude. Moreover, this enhancement was selective for the antigen included in these complexes and did not affect the presentation of a free peptide or of antigen bound to CR1/2 excluded from the complexes. These results suggest that B cells may bind various C3d-coated antigens at a time, but only the one which reacts with the BCR will be processed with high efficiency. This mechanism may ensure the specificity of cognate T cell help.  相似文献   
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Peptidyl epitope recognition by several murine monoclonal antibodies (MAbs E29, H23, HMFG-1, HMFG-2, MA5, MA6 and MA9) which react with the polymorphic epithelial mucins [PEM; epithelial membrane antigen (EMA)] was studied by using ten synthetic peptides representative of the 20 residue tandem repeat as test antigens. Antibody binding to 6-10 residue overlaps and to peptides having a common carboxy-terminus and staggered amino-termini (8-31 residues) was assessed by solid phase and competition ELISA techniques. From these analyses, all MAbs except MA9 were found to react predominantly with the carboxy-terminal half of the repeat motif. Polyclonal antibody responses in mice immunized with intact EMA/PEM-containing preparations also displayed significant reactivities against synthetic repeat peptide antigens and, conversely, synthetic peptides as carrier-conjugated immunogens induced antibodies recognizing intact antigens. These results are discussed vis-à-vis peptide conformation, the potential effects of O-glycosylation on secondary structure, and the possible effects of these parameters on immunogenicity and antigenicity.  相似文献   
35.
BACKGROUND: The aetiology and factors leading to the progression of laryngeal cancer are still unclear. Although human papillomavirus (HPV) has been suggested to play a role, reports concerning the effect of HPV infection on tumour development are controversial. Recently, transfusion transmitted virus (TTV) was suggested to play a role in certain infections as a causative or coinfecting agent. AIMS: To investigate whether the development and progression of laryngeal squamous cell carcinoma is associated with coinfection with TTV and HPV. METHODS: The prevalence of TTV and HPV was investigated using the polymerase chain reaction in tissue samples from 40 healthy individuals, 10 patients with recurrent papillomatosis, five patients with papillomatosis with malignant transformation, and 25 patients with laryngeal carcinoma. The obtained prevalence data were compared and analysed statistically. RESULTS: In the 11 patients with carcinoma who had metastasis or relapse there was a high rate of coinfection with genogroup 1 TTV and HPV (eight of 11), whereas in the 14 without tumour progression no coinfection was found. Coinfection was associated with significantly lower tumour free survival in patients with carcinoma (p < 0.001). Furthermore, four of five patients who had papillomatosis with malignant transformation were coinfected with genogroup 1 TTV and HPV. CONCLUSIONS: Although the nature of cooperation between HPV and TTV needs to be investigated further, coinfection with genogroup 1 TTV and HPV appears to be associated with poor clinical outcome in laryngeal cancer.  相似文献   
36.
BACKGROUND: The mean urine BK viral load in kidney transplant recipients increases with the intensity of infection as the infection progresses from transient viruria to sustained viremia. OBJECTIVES: This study investigated whether the intensity of infection is associated with the humoral immune response. STUDY DESIGN: We measured BKV-specific IgG antibody titers in stored samples obtained serially over a 1-year period from 70 kidney transplant recipients with BKV infection and 17 control recipients without active BKV infection. RESULTS: The mean pre-transplant BKV antibody level was lower in recipients who developed viremia than the mean level in those who never developed viremia (p=0.004). Mean antibody titers in recipients who never showed evidence of active BKV infection rose slightly after transplant despite immunosuppression. The magnitude of the rise in the mean antibody titers in recipients who developed active BKV infection correlated with the intensity of infection (p<0.001). CONCLUSIONS: The mean antibody level increased in accordance with the intensity of the infection post-transplant. Pre-transplant seropositivity did not protect against sustained viremia and the antibody response was not associated with clearance of the virus.  相似文献   
37.
A recombinant pseudorabies (Aujeszky’s disease) virus (PrV) designated as vE16lac was constructed by deleting a 3-kbp DNA segment spanning the junction of long and short components of the viral genome, and by replacing the deleted segment with a lacZ-expression cassette. The aim of constructing this mutant was (a) to determine whether the terminal repeat (Tr) can serve as a template for the regeneration of the internal repeat (Ir), and (b) whether this deletion causes a reduction in the neuroinvasiveness of the virus. To analyze the mechanism of equalization, revertant viruses were selected and structurally characterized from vE16lac infection of PK-15 cells, mice and pigs. Because all revertants acquired Ir sequences identical to that of the wild-type virus, the equalization process occurred using the Tr as a template to reconstitute the Ir. We also found that the recombinant virus vE16lac was virulent in both pigs and mice. The data are discussed in view of studies performed with similar PrV mutants by other authors (Rall et al., 1992, Dean and Cheung, 1995 and Dean et al., 1996). This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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39.
Integrin-mediated cell-matrix interactions are essential for development, tissue homeostasis, and repair. Upon ligand binding, integrins are recruited into focal adhesions (FAs). Integrin-linked kinase (ILK) is an FA component that interacts with the cytoplasmic domains of integrins, recruits adaptor proteins that link integrins to the actin cytoskeleton, and phosphorylates the serine/threonine kinases PKB/Akt and GSK-3beta. Here we show that mice lacking ILK expression die at the peri-implantation stage because they fail to polarize their epiblast and to cavitate. The impaired epiblast polarization is associated with abnormal F-actin accumulation at sites of integrin attachments to the basement membrane (BM) zone. Likewise, ILK-deficient fibroblasts showed abnormal F-actin aggregates associated with impaired cell spreading and delayed formation of stress fibers and FAs. Finally, ILK-deficient fibroblasts have diminished proliferation rates. However, insulin or PDGF treatment did not impair phosphorylation of PKB/Akt and GSK-3beta, indicating that the proliferation defect is not due to absent or reduced ILK-mediated phosphorylation of these substrates in vivo. Furthermore, expression of a mutant ILK lacking kinase activity and/or paxillin binding in ILK-deficient fibroblasts can rescue cell spreading, F-actin organization, FA formation, and proliferation. Altogether these data show that mammalian ILK modulates actin rearrangements at integrin-adhesion sites.  相似文献   
40.
Dark neurons were produced in the cortex of the rat brain by hypoglycemic convulsions. In the somatodendritic domain of each affected neuron, the ultrastructural elements, except for disturbed mitochondria, were remarkably preserved during the acute stage, but the distances between them were reduced dramatically (ultrastructural compaction). Following a 1-min convulsion period, only a few neurons were involved and their environment appeared undamaged. In contrast, 1-h convulsions affected many neurons and caused swelling of astrocytic processes and neuronal dendrites (excitotoxic neuropil). A proportion of dark neurons recovered the normal structure in 2 days. The non-recovering dark neurons were removed from the brain cortex through two entirely different pathways. In the case of 1-h convulsions, their organelles swelled, then disintegrated and finally dispersed into the neuropil through large gaps in the plasma membrane (necrotic-like removal). Following a 1-min convulsion period, the non-recovering dark neurons fell apart into membrane-bound fragments that retained the compacted interior even after being engulfed by astrocytes or microglial cells (apoptotic-like removal). Consequently, in contrast to what is generally accepted, the dark neurons produced by 1-min hypoglycemic convulsions do not die as a consequence of necrosis. As regards the case of 1-h convulsions, it is assumed that a necrotic-like removal process is imposed, by an excitotoxic environment, on dark neurons that previously died through a non-necrotic pathway. Apoptotic neurons were produced in the hippocampal dentate gyrus by intraventricularly administered colchicine. After the biochemical processes had been completed and the chromatin condensation in the nucleus had reached an advanced phase, the ultrastructural elements in the somatodendritic cytoplasm of the affected cells became compacted. If present in an apparently undamaged environment such apoptotic neurons were removed from the dentate gyrus through the apoptotic sequence of morphological changes, whereas those present in an impaired environment were removed through a necrotic-like sequence of morphological changes. This suggests that the removal pathway may depend on the environment and not on the death pathway, as also assumed in the case of the dark neurons produced by hypoglycemic convulsions.  相似文献   
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