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991.

Objective

To evaluate the impact of rubella vaccination strategies on the rates of acquired rubella and congenital rubella syndrome in the Americas.

Methods

We conducted a systematic review of the literature (MEDLINE, PubMed, EMBASE, Cochrane Library, Artemisa Database, LILACS Database, Evidence Portal, VHL-PAHO Portal, Scielo, and Grey-Literature sources) that was published from 1969–2010. We included studies on rubella incidence and seroprevalence rates that were associated with rubella vaccination. The quality of the studies was evaluated according to international guidelines.

Results

A total of 14 studies were identified: 2 clinical trials, 2 cohort studies, 3 transversal studies, 5 ecological studies, and 2 mathematical models. Childhood vaccination reduced the incidence of rubella by 23.6% to 99.6%, increased the occurrence of epidemic cycles in Argentina and in the United States, and shifted the illness to susceptible adults. Vaccination strategies that focused on women and children in Brazil were associated with a 5.5-fold greater incidence of rubella in men leading to new outbreaks and CRS. A combined vaccination strategy with a universal approach that included routine vaccination for boys, girls, women, and men in Mexico and in Costa Rica reduced the incidence of rubella by more than 98% and led to absence of CRS since 2008. A medium and a low risk of bias were found in 3 and 4 articles, respectively.

Conclusion

The results of this review demonstrate that the combined vaccination strategy with a universal approach was the most effective strategy as evidenced by a drastic reduction in the number of cases and the interruption of endemic transmission of rubella in the Americas.  相似文献   
992.
The neuropathological hallmark of Parkinson's disease is the loss of dopaminergic neurons in the pars compacta of the substantia nigra (SNc). The degenerative process starts unilaterally and spreads to the dopaminergic system of both hemispheres. However, the complete characterization of the nigra lesion and the subsequent changes in basal ganglia nuclei activity has not yet been achieved in vivo. The aim of this study was to characterize the time course of the nigral lesion in vivo, using longitudinal T2 relaxometry and diffusion tensor imaging, and the changes in basal ganglia nuclei activity, using manganese-enhanced magnetic resonance imaging, in 6-hydroxydopamine (6-OHDA)-lesioned rats. Our results showed that a unilateral SNc lesion induces bilateral alterations, as indicated by the enhancement of magnetic resonance imaging T2 relaxation times in both the ipsilateral and contralateral SNc. Moreover, axial and radial diffusivities demonstrated bilateral changes at 3 and 14 days after 6-OHDA injection in the pars reticulata of the substantia nigra and cortex, respectively, in comparison to the sham group, suggesting bilateral microstructural alterations in these regions. Unexpectedly, manganese-enhanced magnetic resonance imaging showed decreased axonal transport from the ipsilateral subthalamic nucleus to the ventral pallidum in 6-OHDA-lesioned animals compared with the sham group. These findings demonstrate, for the first time in vivo, the temporal pattern of bilateral alteration induced by the 6-OHDA model of Parkinson's disease, and indicate decreased axonal transport in the ipsilateral hemisphere.  相似文献   
993.
The early events in Junín virus (JUNV) infection are not thoroughly understood. We have previously shown that JUNV enter cells by clathrin-mediated endocytosis. In this report we examine the role of microfilaments and microtubules during early virus infection. Inhibitory effects of drugs affecting main cytoskeletal components on JUNV entry into Vero cells were analyzed. Drugs that disrupted microfilaments or stabilized microtubules inhibited early steps of virus entry. In contrast, drugs that stabilized microfilaments or depolymerized microtubules were not able to block virus entry very efficiently. Furthermore, real time PCR was performed to detect viral entry and we found more than 10-fold less RNA when microfilaments were depolymerized while a 100-fold diminution was seen when microtubules were stabilized. Taken together our results demonstrate that JUNV relies on an intact actin network during early infection in Vero cells while a dynamic microtubule network is also needed. This represents an important contribution to the characterization of arenavirus multiplication cycle.  相似文献   
994.
Chemokines and cytokines play an important role in the inflammatory development and progression of autoimmune diseases. The aim of the present study was to evaluate the role of MCP-1, SDF-1, and RANTES polymorphisms as susceptibility markers for systemic lupus erythematosus (SLE) in a group of Mexican patients. MCP-1-2518, SDF-1 G801A, and RANTES-28 polymorphisms were determined in 242 patients with SLE and 220 ethnically matched healthy controls by the polymerase chain reaction–restriction fragment length polymorphism technique. The differences between patients and healthy controls were evaluated by χ2, Fisher’s exact test, and Woolf method for odds ratio. A moderately increased frequency of MCP-1-2518 A allele (p = 0.033, pC = NS) and AA genotype (p = 0.017, pC = NS) existed in SLE patients compared with healthy controls. There was a relationship between polymorphisms and some clinical and laboratory characteristics. SLE patients with and without antiphospholipid syndrome demonstrated different distribution of SDF-1 G801A genotype frequencies. On the other hand, patients with leukopenia, anti-dsDNA, and antiphospholipid autoantibodies demonstrated different MCP-1-2518 genotype distribution compared with patients without these features. Our results suggest that MCP-1 polymorphism is moderately associated with the genetic susceptibility to SLE in Mexican individuals. The polymorphisms could be related to specific clinical and laboratory characteristics in these patients.  相似文献   
995.
Emetine is one of the two active ingredients of syrup of ipecac which is used medicinally as antiparasitic and emetic, however little is known about its genotoxic activity. The goal of this study was to determine whether and how emetine and/or its metabolites might produce mitotic recombination using the in vivo Drosophila w/w+ eye somatic assay. A standard strain (which expresses basal levels of cytochrome P450 enzymes) and an insecticide-resistant strain (which constitutively over-expresses P450 genes) were employed. The results showed that emetine and/or its metabolites are active in the assay and that the genotoxic potential is significantly influenced in the presence of higher than normal concentrations of P450.  相似文献   
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997.
The influence of genetic factors in rheumatoid arthritis (RA) has been described, including several cytokine genes such as transforming growth factor ?? (TGF-??) with regulatory effects on lymphocytes, dendritic cells, macrophages, chondrocytes, and osteoblasts, which are important in the RA pathogenesis. The G915C TGF-??1 polymorphism has been associated with soluble TGF-??1 (sTGF-??) serum levels. Thus, we studied the association of G915C (Arg25Pro) TGF-??1 polymorphism with sTGF-??1 serum levels in RA. We enrolled 120 RA patients and 120 control subjects (CS). The G915C TGF-??1 polymorphism was determined by polymerase chain reaction?Crestriction fragment length polymorphism (PCR?CRFLP) method, and sTGF-??1 serum levels were quantified using an ELISA kit. The genotype frequency of G915C TGF-??1 polymorphism in RA and CS was G/G (91.7%), G/C (8.3%), C/C (0%) and G/G (85.8%), G/C (14.2%), C/C (0%), respectively, without significant differences. Moreover, the G/G TGF-??1 genotype carriers presented the highest disability index evaluated for the Spanish HAQ-DI score (P?<?0.001). In addition, the sTGF-??1 serum levels were higher in RA (182.2?ng/mL) than CS (160.2?ng/mL), there was not significant difference. However, we found a positive correlation between the sTGF-??1 serum levels and the functional class (r?=?0.472, P?=?0.023). In conclusion, the G915C (Arg25Pro) TGF-??1 polymorphism is not associated with RA, but the sTGF-??1 serum levels are related with the functional class in RA.  相似文献   
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