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71.
The Foodborne Viruses in Europe network has developed integrated epidemiological and virological outbreak reporting with aggregation and sharing of data through a joint database. We analyzed data from reported outbreaks of norovirus (NoV)-caused gastroenteritis from 13 European countries (July 2001 to July 2006) for trends in time and indications of different epidemiology of genotypes and variants. Of the 13 countries participating in this surveillance network, 11 were capable of collecting integrated epidemiological and virological surveillance data and 10 countries reported outbreaks throughout the entire period. Large differences in the numbers and rates of reported outbreaks per country were observed, reflecting the differences in the focus and coverage of national surveillance systems. GII.4 strains predominated throughout the 5-year surveillance period, but the proportion of outbreaks associated with GII.4 rose remarkably during years in which NoV activity was particularly high. Spring and summer peaks indicated the emergence of genetically distinct variants within GII.4 across Europe and were followed by increased NoV activity during the 2002-2003 and 2004-2005 winter seasons. GII.4 viruses predominated in health care settings and in person-to-person transmission. The consecutive emergence of new GII.4 variants is highly indicative of immune-driven selection. Their predominance in health care settings suggests properties that facilitate transmission in settings with a high concentration of people such as higher virus loads in excreta or a higher incidence of vomiting. Understanding the mechanisms driving the changes in epidemiology and clinical impact of these rapidly evolving RNA viruses is essential to design effective intervention and prevention measures.  相似文献   
72.
For best hearing sensation, electrodes of auditory prosthesis must have an optimal electrical contact to the respective neuronal cells. To improve the electrode-nerve interface, microstructuring of implant surfaces could guide neuronal cells toward the electrode contact. To this end, femtosecond laser ablation was used to generate linear microgrooves on the two currently relevant cochlear implant materials, silicone elastomer and platinum. Silicone surfaces were structured by two different methods, either directly, by laser ablation or indirectly, by imprinting using laser-microstructured molds. The influence of surface structuring on neurite outgrowth was investigated utilizing a neuronal-like cell line and primary auditory neurons. The pheochromocytoma cell line PC-12 and primary spiral ganglion cells were cultured on microstructured auditory implant materials. The orientation of neurite outgrowth relative to the microgrooves was determined. Both cell types showed a preferred orientation in parallel to the microstructures on both, platinum and on molded silicone elastomer. Interestingly, microstructures generated by direct laser ablation of silicone did not influence the orientation of either cell type. This shows that differences in the manufacturing procedures can affect the ability of microstructured implant surfaces to guide the growth of neurites. This is of particular importance for clinical applications, since the molding technique represents a reproducible, economic, and commercially feasible manufacturing procedure for the microstructured silicone surfaces of medical implants.  相似文献   
73.
Particle-mediated epidermal delivery (PMED) of allergen genes efficiently prevents systemic sensitization and suppresses specific immunoglobulin E synthesis. We investigated in a mouse model of allergic airway disease the effect of PMED on the elicitation of local inflammatory reactions in the lung. BALB/c mice were biolistically transfected with plasmids encoding beta-galactosidase (betaGal) as model allergen under control of the DC-targeting fascin promoter and the ubiquitously active cytomegalovirus promoter, respectively. Mice were challenged intranasally with betaGal-protein with or without intermediate sensitization with betaGal adsorbed to aluminiumhydroxide. Subsequently, local cytokine production and recruitment of IFN-gamma-producing CD8(+) effector T cells into the airways were determined, and inflammatory parameters such as cellular infiltration in the bronchoalveolar lavage (BAL) and airway hyperresponsiveness (AHR) were measured. PMED of betaGal-encoding plasmids before sensitization significantly reduced frequencies of eosinophils in the BAL and shifted the local T helper (Th) cell response from a distinct Th2 response toward a Th1-biased response. However, AHR triggered by allergen challenge via the airways was not alleviated in vaccinated mice. Most important, we show that PMED using betaGal-encoding DNA without subsequent sensitization recruited Tc1 cells into the lung and caused a Th1-prone local immune response after subsequent intranasal provocation, accompanied by neutrophilic infiltration into the airways and elicitation of AHR. We conclude that robust Th1/Tc1 immune responses, although highly effective in the counter-regulation of local Th2-mediated pathology, might as well trigger local inflammatory reactions in the lung and provoke the induction of AHR in the mouse model of allergic airway disease.  相似文献   
74.
Identification of a novel astrovirus in a domestic pig in Hungary   总被引:1,自引:0,他引:1  
The family Astroviridae consists of two genera, Avastrovirus and Mamastrovirus, whose members are associated with gastroenteritis in avian and mammalian hosts, respectively. We serendipitously identified a novel porcine astrovirus in a fecal specimen from a domestic pig (Sus scrofa domestica) in Hungary. Sequencing of a fragment indicated that it was an ORF1b/ORF2/3′UTR sequence, and it has been submitted to the database as porcine astrovirus type 2 (PAstV-2/Hungary/2007) with accession number GU562296. Its unique sequence characteristics and its phylogenetic position suggest that PAstV-2 could be an important link between previously reported astroviruses and that a genetically divergent lineage of astroviruses exist in piglets.  相似文献   
75.
Papillary renal cell carcinoma is the second most common malignant renal epithelial tumor and constitutes approximately 15% of renal cell tumors. However, papillary architecture is neither unique to papillary renal cell carcinoma, nor do all papillary renal cell carcinomas show exclusive papillary histology. Many of the nonpapillary renal cell carcinomas with papillary architecture have been recognized only recently. Distinction of these from papillary renal cell carcinoma is essential, as biologic behavior and potential therapeutic options are distinct in many such tumors. Close attention to the cytologic and growth pattern characteristics will allow us to arrive at the proper diagnosis in most cases, although sometimes immunohistochemistry and rarely genetic evaluation may be needed.  相似文献   
76.
European Journal of Clinical Microbiology & Infectious Diseases - To evaluate current fluconazole treatment regimens in critically ill adults over the typical treatment course. Data from...  相似文献   
77.
Piwi-interacting RNAs (piRNAs) are essential for silencing of transposable elements in the germline, but their biogenesis is poorly understood. Here we demonstrate that MOV10L1, a germ cell–specific putative RNA helicase, is associated with Piwi proteins. Genetic disruption of the MOV10L1 RNA helicase domain in mice renders both MILI and MIWI2 devoid of piRNAs. Absence of a functional piRNA pathway in Mov10l1 mutant testes causes loss of DNA methylation and subsequent derepression of retrotransposons in germ cells. The Mov10l1 mutant males are sterile owing to complete meiotic arrest. This mouse mutant expresses Piwi proteins but lacks piRNAs, suggesting that MOV10L1 is required for piRNA biogenesis and/or loading to Piwi proteins.  相似文献   
78.
DMP-quo vadis?     
Disease management programs, which have been in existence since 2002, were originally linked financially to the risk structure adjustment (RSA). Analyses of the DMP results have been available since 2007, demonstrating generally good results. DMP have been linked to the morbidity-oriented RSA and the so-called health insurance fund management fee. DMP will change their structure and links to quality parameters in the coming years and will need to be better adapted to multimorbidity and risk-appropriate interventions.  相似文献   
79.
80.
Epidermolysis bullosa simplex (EBS) is a skin disorder caused by fully‐penetrant mutations in the keratin genes KRT5 and KRT14, leading to extensive cytolysis and cell fragility of basal keratinocytes. EBS is subject to environmental conditions and displays high intra‐ and interfamilial variability, suggesting modifying loci. Here, we demonstrate that upregulation of certain cytokines accompanies mutations in keratin 5 (K5) but not in keratin 14 (K14). We find for the first time that cytokines macrophage chemotactic protein (MCP)‐1/[chemokine (C‐C motif) ligand 2] (CCL2), macrophage inflammatory protein (MIP)‐3β/CCL19 and MIP‐3α/CCL20, all regulated by nuclear factor kappa B (NFκB) and involved in the recruitment, maturation, and migration of Langerhans cells (LCs) in the epidermis, are upregulated in the skin of K5–/–, but not of K14–/– mice. In neonatal K5–/– epidermis, the number of LCs was increased two‐fold. At the same time, tumor necrosis factor alpha (TNFα) remained unaltered, demonstrating the specificity of that process. Most remarkably, enhanced LC recruitment within the epidermis was found in five EBS patients carrying mutations in the KRT5 gene but not in EBS patients with KRT14 gene mutations. In agreement with the NFκB‐dependent regulation of these cytokines, we found a decrease in p120‐catenin in the basal epidermis of K5–/– mice. These data provide the first explanation for distinct, keratin‐type‐specific genotype–phenotype correlations in EBS and represent a rationale to investigate gene loci affecting skin pathology in EBS. Hum Mutat 0, 1–10, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
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