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71.

Background

Primary care is increasingly interested in the identification of frailty, as it selects the target population for integrated care. However, instruments for the identification of frailty specifically validated for use in primary care are scarce. This study developed the Easycare Two-step Older persons Screening (Easycare-TOS), which provides a valid, efficient, and pragmatic screening procedure to identify frail older people.

Aim

This paper aims to describe the development of the Easycare-TOS and the data from the pilot studies.

Design and setting

Observational pilot study in seven academic GP practices in and around Nijmegen, The Netherlands.

Method

The Easycare-TOS was developed in a cyclic process with the input of stakeholders. In every cycle, the requirements were first defined, then translated into a prototype that was tested in a pilot study. The Easycare-TOS makes optimal use of prior knowledge of the GP, and the professionals’ appraisal is decisive in the frailty decision, instead of a cut-off score. Further, it considers aspects of frailty, as well as aspects of the care context of the patient.

Results

The pilot data have shown that after step 1, two-thirds of the patients do not need further assessment, because they are judged as not frail, based on prior knowledge of the GP. The overall prevalence of frailty in this pilot study is 24%. Most professionals who participated in the pilot studies considered the time investment acceptable and the method to be of added value.

Conclusion

The Easycare-TOS instrument meets the predefined efficiency, flexibility, and acceptability requirements for use as an identification instrument for frailty in primary care.  相似文献   
72.
Avian pathogenic Escherichia coli (APEC) causes respiratory and systemic disease in poultry. Sequencing of a multilocus sequence type 95 (ST95) serogroup O1 strain previously indicated that APEC resembles E. coli causing extraintestinal human diseases. We sequenced the genomes of two strains of another dominant APEC lineage (ST23 serogroup O78 strains χ7122 and IMT2125) and compared them to each other and to the reannotated APEC O1 sequence. For comparison, we also sequenced a human enterotoxigenic E. coli (ETEC) strain of the same ST23 serogroup O78 lineage. Phylogenetic analysis indicated that the APEC O78 strains were more closely related to human ST23 ETEC than to APEC O1, indicating that separation of pathotypes on the basis of their extraintestinal or diarrheagenic nature is not supported by their phylogeny. The accessory genome of APEC ST23 strains exhibited limited conservation of APEC O1 genomic islands and a distinct repertoire of virulence-associated loci. In light of this diversity, we surveyed the phenotype of 2,185 signature-tagged transposon mutants of χ7122 following intra-air sac inoculation of turkeys. This procedure identified novel APEC ST23 genes that play strain- and tissue-specific roles during infection. For example, genes mediating group 4 capsule synthesis were required for the virulence of χ7122 and were conserved in IMT2125 but absent from APEC O1. Our data reveal the genetic diversity of E. coli strains adapted to cause the same avian disease and indicate that the core genome of the ST23 lineage serves as a chassis for the evolution of E. coli strains adapted to cause avian or human disease via acquisition of distinct virulence genes.  相似文献   
73.
Genomic DNA from 19 Japanese patients with congenital lipoid adrenal hyperplasia (lipoid CAH) representing 16 different families was examined to identify the genetic alterations of steroidogenic acute regulatory protein (StAR). Ten of 19 patients had a 46,XX karyotype and nine had a 46,XY karyotype. Six of the 46,XX patients have experienced spontaneous pubertal changes including breast development and irregular menstruation whereas none of the 46,XY subjects displayed pubertal changes. Eight different mutations were identified. Sixteen patients were either homozygotes or compound heterozygotes for the Q258X mutation. The seven other mutations identified were 189delG, 246insG, 564del13bp, 838delA, Q212X, A218V and M225T. The 189delG, 246insG, 546del13bp and Q212X mutants encode truncated proteins. COS-1 cells transfected with expression vectors encoding cDNAs for the mutant StAR proteins which affect the C-terminus, 838delA, A218V and Q258X, exhibited no steroidogenesis enhancing activity. However, the M225T mutant retained some steroidogenic activity. The patient with the M225T mutation had late onset of this disorder and some capacity to secrete testosterone in response to hCG. These findings suggest: (i) that the Q258X mutation can be used as a genetic marker for the screening of Japanese for lipoid CAH, (ii) that the C-terminus of StAR plays an important role in the protein's activity and (iii) that there are differences in the extent of functional impairment of the testis and ovaries in lipoid CAH.   相似文献   
74.
Superoxide, an agent which attenuates the half-life of nitric oxide, is metabolized and synthesized by superoxide dismutase (SOD) and xanthine oxidase, respectively. Over the last few years much work has focused on the role of nitric oxide in human parturition. The aim of this study was to determine whether the onset of human parturition is associated with a change in the expression of copper/zinc superoxide dismutase (Cu/Zn SOD), manganese superoxide dismutase (Mn SOD) or xanthine oxidase within the uterus. Samples of myometrium, placenta, decidua and fetal membranes were obtained from women before and after the onset of labour at term. Immunocytochemistry was used to localize Cu/Zn SOD, Mn SOD and xanthine oxidase and measure SOD enzyme activity. Cu/Zn and Mn SOD-like immunoreactivity was detected in syncytiotrophoblast cells, villous stromal cells and endothelial cells of blood vessels in the placenta. In the myometrium Cu/Zn and Mn SOD were localized to myocytes and endothelial cells and to some vascular smooth muscle cells. In the fetal membranes we observed staining for Cu/Zn SOD and Mn SOD in the amnion, chorion, extravillous trophoblast and decidua. There was no difference in SOD enzyme activity or staining intensity for SOD between different cell types before and during labour. Xanthine oxidase immunoreactivity was identified in each of the tissues examined and again there was no difference in immunostaining in tissues obtained from women delivered before or after the onset of labour. These results show that the pregnant uterus is capable of both synthesizing and degrading superoxide and suggest that superoxide dismutase and xanthine oxidase may play a role in the maintenance of uterine quiescence during pregnancy, but not in the initiation of parturition.   相似文献   
75.
Oxygen radical generation is known to be detrimental to sperm function, especially motility, through the lipid peroxidation of the membranes. Generation of reactive oxygen species can be induced by leukocyte contamination, sperm centrifugation and the presence of abnormal spermatozoa with excess residual cytoplasm. This study aims to evaluate the effect on sperm motility of incubation in an antioxidant-containing solution, during liquefaction and centrifugation. Thirty semen samples were each divided into two equal parts: one mixed with Tyrode's solution, the other with a salt solution containing antioxidants (Sperm- Fit; Ellios Bio-Media, Paris, France). All the procedures were identical in the two groups. The ratio of leukocytes to spermatozoa was significantly correlated with the motility after liquefaction and after a 24 h incubation in routine in-vitro fertilization (IVF) medium and with the number of motile spermatozoa recovered after Percoll preparation. Moreover, when this ratio was > or = 0.2, all motility parameters were lowered. Incubation with Sperm-Fit allowed a higher percentage of motility after Percoll preparation when the ratio was > or = 0.2 (48 +/- 5% versus 41 +/- 6% for Sperm-Fit and Tyrode's solution respectively; P < 0.05) and a greater number of motile spermatozoa recovered after Percoll preparation, whatever the ratio (3.2 +/- 1.0 x 10(6) versus 2.4 +/- 0.7 x 10(6) for Sperm-Fit and Tyrode's solution respectively when ratio > or = 0.2; 18.1 +/- 3.4 x 10(6) versus 14.4 +/- 2.9 x 10(6) for Sperm-Fit and Tyrode's solution respectively when ratio < 0.2; P < 0.05). These results show that incubation with antioxidants during liquefaction and centrifugation increases recovery of motile spermatozoa.   相似文献   
76.
BACKGROUND: Chronic urticaria (CU) in childhood remains a challenge for investigation, and its etiology is largely unknown. Autoantibodies to the high-affinity IgE receptor (FcepsilonRI) are believed to play a role in the pathogenesis of this disease in adults. OBJECTIVE: To determine the prevalence of autoantibodies to FcepsilonRIalpha on basophils in children with CU vs atopic eczema dermatitis syndrome (AEDS). METHODS: Eighty children with CU were compared with 38 children with AEDS. In addition to complete blood cell counts and total IgE measurements, CAP-RASTs to egg, codfish, soy, milk, and peanut were performed. Stool samples were examined for parasites, and autologous serum skin testing and a functional anti-FcepsilonRIalpha assay were conducted to detect autoantibodies. RESULTS: No significant differences were observed between children with CU and controls in mean basophil or eosinophil counts. Twenty (26%) of 77 children with CU and 31 (82%) of 38 with AEDS had positive CAP-RAST results (P < .001). Only 2.5% of the children with CU and 0% with AEDS had stool samples positive for parasites (P = .005). Anti-FcepsilonRIalpha autoantibodies were positive in 37 (47%) of 78 children with CU and in none of 33 with AEDS. Non-IgG histamine-releasing factors were found in 10 (13%) of 78 children with CU. CONCLUSIONS: Children have a similar prevalence of autoantibodies to the FcepsilonRIalpha as has been previously published for adults. Few have type I allergies, and parasite infestation is also uncommon. Further studies are required to investigate the predictive value of the autoantibodies in these children with respect to clinical profile, requirements for medications other than antihistamines, and remission rates.  相似文献   
77.
Dendritic cells expanded from mouse bone marrow (BMDC) with granulocyte/macrophage-colony-stimulating factor have potent T cell-stimulatory properties both in vitro and in vivo. This has been well documented for major histocompatibility complex (MHC) class II-restricted responses, and more recently using peptide-loaded and protein-pulsed DC for CD8 responses following adoptive transfer in mice. An unresolved question concerns the capacity of BMDC to present exogenous antigen on MHC class I molecules, an unconventional mode of MHC class I loading for which there is now considerable evidence, particularly in macrophages. Here, we show that BMDC exhibit high levels of macropinocytosis driven by constitutive membrane ruffling activity. Up to one-third of actively ruffling and macropinocytosing BMDC transferred pinocytosed horseradish peroxidase into the cytosol following a 15-min pulse, suggesting that they might be capable of presenting exogenous soluble antigen on MHC class I molecules. We show that BMDC presented exogenous ovalbumin to a T cell hybridoma more effectively, more rapidly, and at lower exogenous antigen concentrations than BM macrophages on a cell-for-cell basis. Presentation was TAP dependent, brefeldin A sensitive, and blocked by inhibitors of proteasomal processing, demonstrating use of the classical MHC class I pathway. Although effective presentation of exogenous antigen by BMDC occurred in the absence of agents which stimulate macropinocytosis, treatment with phorbol myristate acetate (PMA) enhanced both pinocytosis and MHC class I presentation by BMDC. Finally, PMA-stimulated BMDC exposed to exogenous ovalbumin in vitro were able to prime an antigen-specific cytotoxic T lymphocyte response following adoptive transfer in vivo.  相似文献   
78.
79.
In this paper, we present a method of quantifying the heterogeneity of cervical cancer tumors for use in radiation treatment outcome prediction. Features based on the distribution of masked wavelet decomposition coefficients in the tumor region of interest (ROI) of temporal dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) studies were used along with the imaged tumor volume to assess the response of the tumors to treatment. The wavelet decomposition combined with ROI masking was used to extract local intensity variations in the tumor. The developed method was tested on a data set consisting of 23 patients with advanced cervical cancer who underwent radiation therapy; 18 of these patients had local control of the tumor, and five had local recurrence. Each patient participated in two DCE-MRI studies: one prior to treatment and another early into treatment (2–4 weeks). An outcome of local control or local recurrence of the tumor was assigned to each patient based on a posttherapy follow-up at least 2 years after the end of treatment. Three different supervised classifiers were trained on combinational subsets of the full wavelet and volume feature set. The best-performing linear discriminant analysis (LDA) and support vector machine (SVM) classifiers each had mean prediction accuracies of 95.7%, with the LDA classifier being more sensitive (100% vs. 80%) and the SVM classifier being more specific (100% vs. 94.4%) in those cases. The K-nearest neighbor classifier performed the best out of all three classifiers, having multiple feature sets that were used to achieve 100% prediction accuracy. The use of distribution measures of the masked wavelet coefficients as features resulted in much better predictive performance than those of previous approaches based on tumor intensity values and their distributions or tumor volume alone.  相似文献   
80.
Rhodococcus equi causes severe pyogranulomatous pneumonia in foals and in immunocompromised humans. Replication of virulent isolates within macrophages correlates with the presence of a large plasmid which encodes a family of seven virulence-associated proteins (VapA and VapC to VapH), whose functions are unknown. Although cell-mediated immunity is thought to be crucial in eliminating R. equi infection, antibody partially protects foals. The antibody response to both VapA and VapC was similar in six adult horses and six naturally exposed but healthy foals, as well as in eight foals with R. equi pneumonia. The immunoglobulin G (IgG) subisotype response of pneumonic foals to Vap proteins was significantly IgGb biased and also had a trend toward higher IgGT association compared to the isotype association of antibody in adult horses and healthy exposed foals. This suggests that in horses, IgGb and IgGT are Th2 isotypes and IgGa is a Th1 isotype. Furthermore, it suggests that foals which develop R. equi pneumonia have a Th2-biased, ineffective immune response whereas foals which become immune develop a Th1-biased immune response. Pneumonic foals had significantly more antibody to VapD and VapE than did healthy exposed foals. This may indicate a difference in the expression of these two Vap proteins during persistent infection. Alternatively, in pneumonic foals the deviation of the immune response toward VapD and VapE may reflect a bias unfavorable to R. equi resistance. These data indicate possible age-related differences in the equine immune response affecting Th1-Th2 bias as well as antibody specificity bias, which together favor the susceptibility of foals to R. equi pneumonia.  相似文献   
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