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11.
Different mathematical expressions have been proposed in the literature with the aim to reflect the risk of calcium oxalate urolithiasis. Such expressions, as well as a number of new relationships proposed by us, have been evaluated in 76 patients and 34 normal subjects. Stone-formers were divided into two groups: patients with normal calcium and oxalate excretion and patients with hypercalciuria and/or hyperoxaluria. The results obtained were comparatively evaluated. Several formulae gave some acceptable results, but none of them were excellent. This can be explained by the fact that these discrimination indexes more or less reflect supersaturation and/or inhibition deficit, but none of them reflect promoting factors such as heterogeneous nucleation and/or aggregation capacity.  相似文献   
12.
Twenty patients with AIDS who had intracranial lesions underwent both brain biopsy and cerebro-spinal fluid (CSF) examination to compare histological diagnosis with the polymerase chain reaction (CSF-PCR) for the identification of infectious agents. CSF-PCR was performed for herpes simplex virus, varicella zoster virus, cytomegalovirus (CMV), JC virus (JCV), Epstein-Barr virus (EBV), Toxoplasma gondii and Mycobacterium tuberculosis. A definitive diagnosis was obtained by brain biopsy in 14 patients (2 with astrocytoma, 12 with brain infection). CSF-PCR was positive for EBV DNA in 3 of 3 cases of primary cerebral lymphoma, positive for JCV DNA in 6 of 7 biopsy-proven (and one autopsy-proven) cases of progressive multifocal leukoencephalopathy (PML). CSF-PCR was positive for CMV DNA in one biopsy-proven and one autopsy-proven case of CMV encephalitis (the former also had PML) and positive for M. tuberculosis DNA in one case of tuberculous encephalitis. None of the five toxoplasmic encephalitis cases (one definite, four presumptive) were T. gondii DNA positive. There was close correlation between histology and CSF-PCR for CMV encephalitis, PML and PCL. Antitoxoplasma therapy affected the sensitivity of both histological and CSF-PCR methods. Received: 8 November 1995 Received in revised form: 9 July 1996 Accepted: 19 July 1996  相似文献   
13.
This article provides a brief overview of the changing nature of the concept of minor depression. It then discusses treatment studies conducted from 1980 to 1991 of patients diagnosed as neurotic depression, depressive neurosis or dysthymia, characterologic depression, "double depression" and minor depression or dysthymia, if there has been a full remission of a major depressive episode lasting at least six months prior to the development of dysthymia. Long-term treatment of chronic depression is also reviewed. Cognitive-behavioral intervention and marital therapy have been reported beneficial for patients diagnosed as having neurotic depression, characterological depression, or dysthymia. All studies of antidepressant drug treatment showed drugs to be efficacious and superior to placebo, with few differences found between drugs. In addition, they all showed the importance of analyzing the interactions between treatment and severity or diagnosis. Patients diagnosed as "double depression" also appear responsive to both psychosocial intervention and drug treatment; in general, however, these patients tend to have a poor long-term outcome and continued treatment is indicated. The most obvious finding to emerge from this review is that the diagnosis of minor depression is ambiguous, in large part because of the lack of defining criteria related to severity and course. The review also revealed that in addition to poorly defined subgroups, many studies lacked controls, had small sample sizes, inadequate and/or inconsistent measures of outcome, and limited follow-up. For these reasons, their findings cannot be considered conclusive. Finally, the literature revealed a dearth of controlled studies of psychosocial treatment for well defined subgroups of neurotic depression.  相似文献   
14.
The erbB2 gene is often found amplified and/or overexpressed in breast cancer in which it has clinical relevance as prognostic and predictive factor. It is involved in growth regulation and has a role in the initial phases of cell proliferation, while in vivo and in vitro studies have suggested an involvement also in cell invasion and metastases. It is not clear if these two roles are mutually exclusive and little is known about the mechanisms by which erbB2 may be involved in the control of these processes. Our previous data on patient series suggested that erbB2 might be regulated in different ways depending on the neoplastic status of the cells and that it might be involved in different regulatory pathways. To test this hypothesis we have measured the serum-dependent regulation of erbB2 as a function of the expression of the antimetastatic gene, nm23, in a panel of breast cancer cell lines. The experimental model consisted of three cell lines having different proliferative and invasive potentials: a non-metastatic estrogen receptor (ER) positive cell line, MCF-7; a highly metastatic ER negative cell line, MDA-MB435; and the MDA-MB435 cell line transfected with the nm23-H1 antimetastatic gene (clone H1-177) which has lost the ability to invade and metastasize. We first analysed the serum concentration dependence of invasion and proliferation after 3-4 days of serum deprivation confirming the proliferative and invasive potential of the three cell lines. Modulation of erbB2 expression by different concentrations of serum was then studied. ErbB2 expression in MCF-7 cells showed a complex pattern due to serum modulation, whereas, it was not longer regulated by serum in the MDA-MB435 cell line. In H1-177 cells the erbB2 response to serum was restored and it was very similar to that observed in MCF-7. These data showed a tight association between nm23 and the regulation of erbB2 expression by serum factors suggesting that the role of erbB2 in invasion might be dependent on nm23 expression.  相似文献   
15.
We determined the spatial dependence of adaptive gain changes of the vertical angular vestibulo-ocular reflex (aVOR) on gravity in five human subjects. The gain was decreased for 1 h by sinusoidal oscillation in pitch about a spatial vertical axis in a subject-stationary surround with the head oriented left-side down. Gains were tested by sinusoidal oscillation about a spatial vertical axis while subjects were tilted in 15° increments from left- to right-side down positions through the upright. Changes in gain of the vertical component of the induced eye movements were expressed as a percentage of the preadapted values for the final analysis. Vertical aVOR gain changes were maximal in the position in which the gain had been adapted and declined progressively as subjects were moved from this position. Gain changes were plotted as a function of head orientation and fit with a sine function. The bias level of the fitted sines, i.e., the gravity-independent gain change, was –29±10% (SD). The gains varied around this bias as a function of head position by ±18±6%, which were the gravity-dependent gain changes. The gravity-dependent gain changes induced by only 1 h of adaptation persisted, gradually declining over several days. We conclude that there is a component of the vertical aVOR gain change in humans that is dependent on the head orientation in which the gain was adapted, and that this dependence can persist for substantial periods.  相似文献   
16.
As a first step toward the design of an epitope vaccine to prevent contagious agalactia, the strongly immunogenic 55-kDa protein of Mycoplasma agalactiae was studied and found to correspond to the AvgC protein encoded by the avgC gene. The avg genes of M. agalactiae, which encode four variable surface lipoproteins, display a significant homology to the vsp (variable membrane surface lipoproteins) genes of the bovine pathogen Mycoplasma bovis at their promoter region as well as their N-terminus-encoding regions. Some members of the Vsp family are known to be involved in cytoadhesion to host cells. In order to localize immunogenic peptides in the AvgC antigen, the protein sequence was submitted to epitope prediction analysis, and five sets of overlapping peptides, corresponding to five selected regions, were synthesized by Spot synthesis. Reactive peptides were selected by immunobinding assay with sera from infected sheep. The three most immunogenic epitopes were shown to be surface exposed by immunoprecipitation assays, and one of these was specifically recognized by all tested sera. Our study indicates that selected epitopes of the AvgC lipoprotein may be used to develop a peptide-based vaccine which is effective against M. agalactiae infection.  相似文献   
17.
Aim—To determine whether the fluorescent in situ hybridisation technique (FISH) using a total human DNA genomic probe can be used to enumerate semen leucocytes.  相似文献   
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19.
The degree of matching of HLA genes between the selected donor and recipient is an important aspect of the selection of unrelated donors for allogeneic bone marrow transplantation (UBMT). The most sensitive methods currently used are serological typing of HLA class I genes, mixed lymphocyte culture (MLC), IEF and molecular genotyping of HLA class II genes by direct sequencing of PCR products. Serological typing of class I antigenes (A, B and C) fails to detect minor differences demonstrated by direct sequencing of DNA polymorphic regions. Molecular genotyping of HLA class I genes by DNA analysis is costly and work-intensive. To improve compatibility between donor and recipient, we have set up a new rapid and non-radioisotopic application of the ‘fingerprinting PCR’ technique for the analysis of the polymorphic second exon of the HLA class I A, B and C genes. This technique is based on the formation of specific patterns (PCR fingerprints) of homoduplexes and heterodu-plexes between heterologous amplified DNA sequences. After an electrophoretic run on non-denaturing polyacrylamide gel, different HLA class I types give allele-specific banding patterns. HLA class I matching is performed, after the gel has been soaked in ethidium bromide or silver-stained, by visual comparison of patients’ fingerprints with those of donors. Identity can be confirmed by mixing donor and recipient DNAs in an amplification cross-match. To assess the technique, 10 normal samples, 22 related allogeneic bone marrow transplanted pairs and 10 unrelated HLA-A and HLA-B serologically matched patient-donor pairs were analysed for HLA class I polymorphic regions. In all the related pairs and in 1/10 unrelated pairs, matched donor-recipient patterns were identified. This new application of PCR fingerprinting may confirm the HLA class I serological selection of unrelated marrow donors.  相似文献   
20.
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