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61.
62.
ABSTRACT: BACKGROUND: Rotavirus (RV) is the commonest cause of acute gastroenteritis in infants and young children worldwide. A Quality of Life study was conducted in primary care in three European countries as part of a larger epidemiological study (SPRIK) to investigate the impact of paediatric rotavirus gastroenteritis (RVGE) on affected children and their parents. METHODS: A self-administered questionnaire was linguistically validated in Spanish, Italian and Polish. The questionnaire was included in an observational multicentre prospective study of 302 children aged <5 years presenting to a general practitioner or paediatrician for RVGE at centres in Spain, Italy or Poland. RV infection was confirmed by polymerase chain reaction (PCR) testing (n = 264). The questionnaire was validated and used to assess the emotional impact of paediatric RVGE on the parents. RESULTS: Questionnaire responses showed that acute RVGE in a child adversely affects the parents' daily life as well as the child. Parents of children with RVGE experience worry, distress and impact on their daily activities. RVGE of greater clinical severity (assessed by the Vesikari scale) was associated with higher parental worries due to symptoms and greater changes in the child's behaviour, and a trend to higher impact on parents' daily activities and higher parental distress, together with a higher score on the symptom severity scale of the questionnaire. CONCLUSIONS: Parents of a child with acute RVGE presenting to primary care experience worry, distress and disruptions to daily life as a result of the child's illness. Prevention of this disease through prophylactic vaccination will improve the daily lives of parents and children.  相似文献   
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64.
Sarcomatoid carcinomas involving the intestinal tract are rare and usually associated with poor prognosis. We report a case of sarcomatoid carcinoma of the ileum, diagnosed in a 61-year-old man. The patient presented with acute intestinal occlusion. Surgical resection of the ileum was performed. At macroscopic examination, two large polypoid masses were found. Frozen section examination suggested the diagnosis of malignant stromal tumor. At histological examination, both tumors were formed by pleiomorphic, large spindle cells, presenting numerous mitoses and marked nuclear atypia. Immunohistochemical examination showed that tumor cells coexpressed vimentin and epithelial markers (cytokeratins, EMA). The final diagnosis was monomorphic sarcomatoid carcinoma. The patient deceased with metastatic disease after 3 months of follow-up. This report underlines the potential diagnostic problems raised by this unusual type of carcinoma and emphasizes the role of immunohistochemistry in assessing the correct diagnosis.  相似文献   
65.
In this work, apolipoprotein A-I (ApoA-I) was purified from pig sera. The responses of this protein after sterile inflammation and in animals infected with Actinobacillus pleuropneumoniae or Streptococcus suis were investigated. Decreases in the concentrations of ApoA-I, two to five times lower than the initial values, were observed at 2 to 4 days. It is concluded that ApoA-I is a negative acute-phase protein in pigs.  相似文献   
66.
We used a GAD65-specific human B-T cell line cognate system in vitro to investigate the modulation of GAD65 presentation by autoantibody, assessed in a proliferation assay. Generally, if the T cell determinant overlaps or resides within the antibody epitope, effects of presentation are blunted while if they are distant can lead to potent presentation. For three different autoreactive B-T cell line cognate pairs, the modulation of GAD65 presentation followed the mode of overlapping or distant epitopes with resultant potent or undetectable presentation. However, other cognate pairs elicited variability in this pattern of presentation. Notably, one B cell line, DPC, whose antibody epitope did not overlap with the T cell determinants, was consistently poor in presenting GAD65. Using the fluorescent dye Alexa Fluor 647 conjugated to GAD65 to study receptor-mediated antigen endocytosis showed that all the antigen-specific B cell clones were efficient in intracellular accumulation of the antigen. Additionally, multicolour immunofluorescence microscopy showed that the internalized GAD65/surface IgG complexes were rapidly targeted to a perinuclear compartment in all GAD-specific B cell clones. This analysis also demonstrated that HLA-DM expression was reduced strongly in DPC compared to the stimulatory B cell clones. Thus the capability of antigen-specific B cells to capture and present antigen to human T cell lines is dependent on the spatial relationship of B and T cell epitopes as well other factors which contribute to the efficiency of presentation.  相似文献   
67.
Crustacean primary cell culture: A technical approach   总被引:10,自引:0,他引:10  
Crustacean cell culture has gained attention as a potent model to assist in the development of diagnostic reagents and probes for use in the shrimp, crayfish and lobster industries. The availability of such cellular tools is especially important to industries which use intensive aquaculture methods and thus have increased risk of disease problems. Indeed, crustacean cell cultures offer potential for studying the effects of pathogens in vitro and for increasing our knowledge on developmental and sexual maturation processes, or endocrine regulation in crustaceans. Although numerous attempts have been undertaken, no established cell line of marine crustaceans has been reported to date. However, primary cultures obtained from various organ sources are reported with increasing frequency. They represent the first steps towards the establishment of cell lines and they provide useful information concerning the most suitable cell culture conditions involved in the survival and proliferative capacity of the various tissues.  相似文献   
68.
Complex I deficiency is a frequent cause of mitochondrial disease as it accounts for one third of these disorders. By genotyping several putative disease loci using microsatellite markers we were able to describe a new NDUFS7 mutation in a consanguineous family with Leigh syndrome and isolated complex I deficiency. This mutation lies in the first intron of the NDUFS7 gene (c.17-1167 C>G) and creates a strong donor splice site resulting in the generation of a cryptic exon. This mutation is predicted to result in a shortened mutant protein of 41 instead of 213 amino acids containing only the first five amino acids of the normal protein. Analysis of the assembly state of the respiratory chain complexes under native condition revealed a marked decrease of fully assembled complex I while the quantity of the other complexes was not altered. These results report the first intronic NDUFS7 gene mutation and demonstrate the crucial role of NDUFS7 in the biogenesis of complex I.  相似文献   
69.
Chemokines and their receptors are part of polarized T helper 1 (Th1)- and Th2-mediated immune responses which control trafficking of immunogenic cells to sites of inflammation. The chemokine stromal cell-derived factor-1 CXCL-12 (SDF-1) and its ligand the CXCR4 chemokine receptor are important regulatory elements. CXCR4 is expressed on the surface of CD4(+) T cells, dendritic cells and B lymphocytes. Levels of CXCR4 mRNA were increased in pancreatic lymph nodes (PLNs) of 4-week-old non-obese diabetic (NOD) mice in comparison to Balb/C mice. However, a significant reduction of CXCR4 was noticed at 12 weeks both at the mRNA and protein levels while expression increased in the inflamed islets. The percentage of SDF-1 attracted splenocytes in a transwell chemotaxis assay was significantly increased in NOD versus Balb/c mice. SDF-1 attracted T cells completely abolished the capacity of diabetogenic T cells to transfer diabetes in the recipients of an adoptive cell co-transfer. When T splenocytes from NOD females treated with AMD3100, a specific CXCR4 antagonist, were mixed with diabetogenic T cells during adoptive cell co-transfer experiments, prevalence of diabetes in the recipients rose from 33% to 75% (P < 0.001). This effect was associated with an increase of interferon (IFN)-gamma mRNA and a reduction of interleukin (IL)-4 mRNA levels both in PLNs and isolated islets. AMD3100 also reduced IL-4 and IL-10 production of plate-bound anti-CD3 and anti-CD28-stimulated splenocytes. Immunofluorescence studies indicated that AMD3100 reduced the number of CXCR4(+) and SDF-1 positive cells in the inflamed islets. We can conclude that the CXCL-12/CXCR4 pathway has protective effects against autoimmune diabetes.  相似文献   
70.
Since antibodies currently constitute the most rapidly growing class of human therapeutics, the high-yield production of recombinant antibodies and antibody fragments is a real challenge. Using as model a monoclonal antibody directed against the human prion protein that we prepared previously and tested for its therapeutic value, we describe here experimental conditions allowing the production of large quantities (up to 35 mg/l of bacterial culture) of correctly refolded and totally functional single chain fragment variable (scFv). These quantities were sufficient to characterize the binding properties of this small recombinant fragment through in vitro and ex vivo approaches. Interestingly, this scFv retains full binding capacity for its antigen, i.e. the human prion protein, when compared with the corresponding Fab or whole antibody, and recognizes soluble, solid-phase-adsorbed, and membrane-bound prion protein. This strongly suggests that from the mAb cloning step to the refolding of the recombinant fragment, each stage is well controlled, leading to almost 100% functional scFv. These results are of interest not only in view of possible immunotherapy for prion diseases, but also more generally in emphasizing the great promise of these small recombinant molecules in the context of targeted therapies.  相似文献   
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