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61.
Testicular germ cell tumours, seminoma (SE) and non-seminoma (NS), of young adult men develop from a precursor cell, carcinoma in situ (CIS), which resembles foetal gonocytes and retains embryonic pluripotency. We used microarrays to analyse microRNA (miRNA) expression in 12 human testis samples with CIS cells and compared it with miRNA expression profiles of normal adult testis, testis with Sertoli-cell-only that lacks germ cells, testis tumours (SE and embryonal carcinoma (EC), an undifferentiated component of NS) and foetal male and female gonads. Principal components analysis revealed distinct miRNA expression profiles characteristic for each of the different tissue types. We identified several miRNAs that were unique to testis with CIS cells, foetal gonads and testis tumours. These included miRNAs from the hsa-miR-371-373 and -302-367 clusters that have previously been reported in germ cell tumours and three miRNAs (hsa-miR-96, -141 and -200c) that were also expressed in human epididymis. We found several miRNAs that were upregulated in testis tumours: hsa-miR-9, -105 and -182-183-96 clusters were highly expressed in SE, while the hsa-miR-515-526 cluster was high in EC. We conclude that the miRNA expression profile changes during testis development and that the miRNA profile of adult testis with CIS cells shares characteristic similarities with the expression in foetal gonocytes.  相似文献   
62.
Summary. Hereditary xerocytosis (HX) is a rare haemolytic disease due to dehydrated red blood cells (RBCs). A unique feature of this syndrome is that affected members often show normal or near normal haemoglobin levels despite clinical and laboratory evidence of mild to moderate haemolysis. The diagnostic clue is the association of markedly increased RBC Na++K+ fluxes with low total cation (Na+ +K+) content. 11 patients of six unrelated families of Spanish origin with HX have been studied from clinical, genetical and biological points of view. In addition, we have investigated the sensitivity of RBC membrane to heat at three different incubation times (15, 30 and 60min) and two different temperature values (46°C and 49°C). Under these conditions control RBCs (50 normal subjects) exhibited at 49°C and 30min a maximum of 30% fragmented RBCs. This value increased to 80% after 60min of incubation. In contrast, patients with HX showed significantly lower percentages of fragmented RBCs at both 30 and 60min of incubation (maximum 10% and 30%, respectively). In an attempt to determine if increased heat stability was unique to HX RBCs, several other congenital membranopathies with haemolytic anaemia were also studied. The degree of fragmentation, except in one case of HPP (which was strongly increased), did not differ from the control group. Electrophoretic studies of membrane proteins performed in RBCs of all the patients with HX did not explain any qualitative nor quantitative abnormality.
In addition to its physiopathological interest, study of RBC heat stability, together with other haematological parameters (increased MCHC and decreased RBC osmotic fragility), may be useful for HX diagnosis, especially in laboratories which are not equipped to evaluate RBC membrane permeability.  相似文献   
63.
HIV-1 viral load falls rapidly on initiation of HAART. This phase of decreasing yet substantial viral production in the presence of antiretroviral drugs could generate resistant HIV-1. Whether switching a drug from a failing regime changes the demography of the mutations associated with it in the CD4+ T-cell compartment is not well-defined. We investigated the presence/absence and quantity of 184M and 184V in the CD4+ T-cell compartment of na?ve patients initiated to HAART (group I), and patients who shifted to a non-lamivudine therapy (group II). We initiated a prospective 90 d follow-up study of 11 patients to detect and quantity proviral HIV-1 184M and 184V in the CD4+ T-cell compartment with a sensitive real time PCR assay. Results showed that the 184V was not detected in the CD4+ T-cell compartment of any of the 7 na?ve patients who started on HAART. Three out of the 4 patients in group II experienced a fall in the percentage of 184V, with reduction to below detection limits in 2 patients. It can be concluded that initiation of HAART does not allow the archiving of the lamivudine associated mutation, 184V, in the CD4+ T-cell compartment. Reduction in the quantity of 184V when therapy is switched to an effective non-lamivudine regime indicates that the mutation in this compartment is dynamic.  相似文献   
64.
Secretion of tumor necrosis factor-α (TNF-α) by macrophages plays a predominant role in the development and progression of rheumatoid arthritis. We demonstrate that knockdown of TNF-α expression in systemic macrophages by intraperitoneal (i.p.) administration of chitosan/small interfering RNA (siRNA) nanoparticles in mice downregulates systemic and local inflammation. Chitosan nanoparticles containing an unmodified anti-TNF-α Dicer-substrate siRNA (DsiRNA) mediated TNF-α knockdown (~66%) in primary peritoneal macrophages in vitro. The presence of Cy3-labeled nanoparticles within peritoneal macrophages and specific TNF-α knockdown (~44%) with TNF-α siRNA after i.p. injection supports our therapeutic approach. Downregulation of TNF-α-induced inflammatory responses arrested joint swelling in collagen-induced arthritic (CIA) mice dosed i.p. with anti-TNF-α DsiRNA nanoparticles. The use of 2′-O-Me-modified DsiRNA resulted in the lowest arthritic scores and correlated with reduced type I interferon (IFN) activation in macrophages in vivo compared with unmodified DsiRNA. Histological analysis of joints revealed minimal cartilage destruction and inflammatory cell infiltration in anti-TNF-α-treated mice. The onset of arthritis could be delayed using a prophylactic dosing regime. This work demonstrates nanoparticle-mediated TNF-α knockdown in peritoneal macrophages as a method to reduce both local and systemic inflammation, thereby presenting a novel strategy for arthritis treatment.  相似文献   
65.
Although favorable effects of débridement with chondrectomy and drilling or abrasion have been reported in treating of cartilage lesions in the knee joint; however, in most cases an additional intervention is generally performed during arthroscopy. We studied 53 consecutive patients with solitary chondral lesions in the weight-bearing part of the knee and treated 86 cartilage lesions by arthroscopic débridement, including a detailed removal of damaged or undermined cartilage. We evaluated the postoperative course by questionnaire (mean follow-up 6.5 years, response rate 83%). All patients reported a positive effect of chondrectomy: 69% considered the knee considerably better or cured and 77% regarded the effect as permanent. There was no complication of the arthroscopies performed, and no patient noted any deterioration in the condition. We therefore recommend routine chondrectomy of cartilage lesions when these are found during an arthroscopy.  相似文献   
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67.
Abstract – For the objective measurement of oral mucosal dryness or moisture, a device registering oral mucosal surface slide friction has been developed. Two prototypes, Probe I and Probe II, have been tested. Probe I was constructed for initial testing of the method and was based on easily accessible electrical components. Probe I was computerized and developed for more accurate registration and also for easy handling. Reliability and validity tests were carried out on Probe I as well as on Probe II. In repeated in vitro measurements, the probes showed good reproducibility. Validity was assessed on healthy subjects injected with methylscopolamine nitrate submucosally in the labial sulcus. All subjects experienced a pronounced oral mucosal dryness within half an hour. Registration with the surface slide friction device showed maximum friction values 1-2 h after injection. These reliability and validity tests gave good results for both Probe I and Probe II, but Probe II had several practical advantages over Probe I. Both probes were considerably more sensitive to changes of the oral mucosal surface than the previously used simple friction test using the back of a mouth mirror.  相似文献   
68.
Immunization of rabbits from a closed colony with streptococcal Group A-variant vaccines identified about two-thirds of them as low and heterogeneous responders. One-third of the rabbits showed a restriction of the response independent from the magnitude. Selective breeding from one monoclonal high-responder male and two restricted high-responder female rabbits succeeded in segregation of high-responder progeny after two generations. Their antibody levels were on the average 2.5 times higher than those of the random group of rabbits and a small group of low-responder offspring. Immunization of 13 offspring originating from rabbits bred for restricted high response to the streptococcal Group C polysaccharide revealed that 11 progeny were restricted high responders and 2 progeny monoclonal high responders. This finding suggests that high responsiveness to the Groups A-variant and C polysaccharides is inherited as genetically linked traits. Selective breeding combinations between restricted and monoclonal high-responder rabbits by brother-sister matings succeeded in narrowing the isoelectric focusing spectra of Group A-variant-specific antibodies in the offspring. It furthermore revealed a preferential expression of monoclonal antibodies after three generations with a similar net charge as those identified first in the original monoclonal paternal parent. These data suggest that similar copies of structural genes for the variable regions are transmitted from the parent to the progeny.  相似文献   
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