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991.
BACKGROUND: A resurgence of Haemophilus influenzae type b (Hib) disease occurred in the United Kingdom between 1999 and 2003 and was partially attributed to lower immunogenicity of combination vaccines. The reservoir for Hib that led to transmission in this period is unknown. METHODS: We estimated the point prevalence of Hib carriage in school-aged children and adults, using oropharyngeal swabbing and selective media. We characterized the Hib isolates by multilocus sequence typing (MLST) and measured Hib antibody concentrations in adults by enzyme-linked immunosorbent assay. RESULTS: Point prevalence for Hib carriage in 855 children aged 6-16 years was 4.2% (95% confidence interval [CI], 2.5%-5.9%). Five clonal groups of Hib were identified by MLST, 86% from the lineage of sequence type 6. No Hib was isolated in 385 adults (upper limit of 95% CI, 0.95%). The geometric mean concentration of serum antibody to polyribosylribitol phosphate was 0.47 microg/mL (95% CI, 0.37-0.59 mirog/mL) in adults. CONCLUSIONS: Hib carriage is common in school-aged children, who are a significant reservoir for ongoing transmission of Hib to susceptible individuals in the United Kingdom. Surveillance of transmission and immunity across all ages of the population is essential to monitor the evolution of Hib epidemiology.  相似文献   
992.
OBJECTIVES: We evaluated whether the angiotensin II (Ang II) receptors from perioperation through one-year post-transplantation predict the transplant coronary artery disease (TCAD) progression. BACKGROUND: The role of Ang II receptors (type 1: AT(1)R; type 2: AT(2)R) in TCAD is uncertain. METHODS: We investigated 28 heart donors and the corresponding recipients. The levels of AT(1)R and AT(2)R messenger ribonucleic acid (mRNA) were examined in lymphocytes from the donor spleen and in the donor heart at one-week and one-year posttransplantation to determine their association with the progression of TCAD, measured as changes in maximal intimal thickness (CMIT) and plaque volume (CPV) by intravascular ultrasound (IVUS) examinations. RESULTS: The AT(1)R mRNA in lymphocytes from the donor spleen (CMIT: r = 0.73, p < 0.0001; CPV: r = 0.69, p < 0.0001) and in the donor hearts at one-week (CMIT: r = 0.52, p = 0.005; CPV: r = 0.56, p = 0.002) and at one-year (CMIT: r = 0.63, p < 0.0001; CPV: r = 0.43, p = 0.004) post-transplantation along with AT(2)R mRNA in the donor hearts at one-year post-transplantation (CMIT: r = 0.3, p < 0.0001; CPV: r = 0.53, p = 0.009) were univariate predictors, whereas AT(1)R mRNA in lymphocytes and in the donor hearts at one-year post-transplantation proved to be multivariate predictors of the progression of TCAD. CONCLUSIONS: These data suggest a role for Ang II receptors in the pathogenesis of TCAD and support a novel concept that TCAD may have its origin in the donor per se and may be modulated by the recipient's inherent biological factors.  相似文献   
993.
PURPOSE OF REVIEW: Basic calcium phosphate crystals are responsible for a number of clinical syndromes. The study of basic calcium phosphate crystal deposition diseases has been hindered by a lack of readily available, accurate, diagnostic tests. Recent data have provided further understanding of the mechanisms by which basic calcium phosphate crystals induce inflammation and degeneration within the joint, as well as their potential role in other conditions such as cancer and atherosclerosis. RECENT FINDINGS: New information on the effects of basic calcium phosphate crystals on matrix metalloproteinases and mitogenesis further supports a role for basic calcium phosphate crystals in the pathogenesis of osteoarthritis. Phosphocitrate remains the most promising of the potential therapeutic agents, which could antagonize the effects of basic calcium phosphate crystals, although other therapies have also been examined. SUMMARY: Further work is needed to clarify the exact role basic calcium phosphate crystals play in the development of osteoarthritis.  相似文献   
994.
Sophie Molnos  Simone Wahl  Mark Haid  E. Marelise W. Eekhoff  René Pool  Anna Floegel  Joris Deelen  Daniela Much  Cornelia Prehn  Michaela Breier  Harmen H. Draisma  Nienke van Leeuwen  Annemarie M. C. Simonis-Bik  Anna Jonsson  Gonneke Willemsen  Wolfgang Bernigau  Rui Wang-Sattler  Karsten Suhre  Annette Peters  Barbara Thorand  Christian Herder  Wolfgang Rathmann  Michael Roden  Christian Gieger  Mark H. H. Kramer  Diana van Heemst  Helle K. Pedersen  Valborg Gudmundsdottir  Matthias B. Schulze  Tobias Pischon  Eco J. C. de Geus  Heiner Boeing  Dorret I. Boomsma  Anette G. Ziegler  P. Eline Slagboom  Sandra Hummel  Marian Beekman  Harald Grallert  Søren Brunak  Mark I. McCarthy  Ramneek Gupta  Ewan R. Pearson  Jerzy Adamski  Leen M. ’t Hart 《Diabetologia》2018,61(1):117-129

Aims/hypothesis

Circulating metabolites have been shown to reflect metabolic changes during the development of type 2 diabetes. In this study we examined the association of metabolite levels and pairwise metabolite ratios with insulin responses after glucose, glucagon-like peptide-1 (GLP-1) and arginine stimulation. We then investigated if the identified metabolite ratios were associated with measures of OGTT-derived beta cell function and with prevalent and incident type 2 diabetes.

Methods

We measured the levels of 188 metabolites in plasma samples from 130 healthy members of twin families (from the Netherlands Twin Register) at five time points during a modified 3 h hyperglycaemic clamp with glucose, GLP-1 and arginine stimulation. We validated our results in cohorts with OGTT data (n = 340) and epidemiological case–control studies of prevalent (n = 4925) and incident (n = 4277) diabetes. The data were analysed using regression models with adjustment for potential confounders.

Results

There were dynamic changes in metabolite levels in response to the different secretagogues. Furthermore, several fasting pairwise metabolite ratios were associated with one or multiple clamp-derived measures of insulin secretion (all p < 9.2 × 10?7). These associations were significantly stronger compared with the individual metabolite components. One of the ratios, valine to phosphatidylcholine acyl-alkyl C32:2 (PC ae C32:2), in addition showed a directionally consistent positive association with OGTT-derived measures of insulin secretion and resistance (p ≤ 5.4 × 10?3) and prevalent type 2 diabetes (ORVal_PC ae C32:2 2.64 [β 0.97 ± 0.09], p = 1.0 × 10?27). Furthermore, Val_PC ae C32:2 predicted incident diabetes independent of established risk factors in two epidemiological cohort studies (HRVal_PC ae C32:2 1.57 [β 0.45 ± 0.06]; p = 1.3 × 10?15), leading to modest improvements in the receiver operating characteristics when added to a model containing a set of established risk factors in both cohorts (increases from 0.780 to 0.801 and from 0.862 to 0.865 respectively, when added to the model containing traditional risk factors + glucose).

Conclusions/interpretation

In this study we have shown that the Val_PC ae C32:2 metabolite ratio is associated with an increased risk of type 2 diabetes and measures of insulin secretion and resistance. The observed effects were stronger than that of the individual metabolites and independent of known risk factors.
  相似文献   
995.
Studies of circulating hemopoietic progenitor cells in human fetal blood   总被引:3,自引:0,他引:3  
Linch  DC; Knott  LJ; Rodeck  CH; Huehns  ER 《Blood》1982,59(5):976-979
High levels of committed erythroid and granulocytic/monocytic progenitor cells have been demonstrated in fresh blood obtained at fetoscopy. The fetal progenitor cells were more sensitive to appropriate stimuli (erythropoietin and colony-stimulating factor) than adult progenitor cells grown under the same conditions, and this was shown to be due to intrinsic differences in the progenitor cells at the different developmental stages.  相似文献   
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Purpose

Vascular endothelial growth factor (VEGF) is the most potent stimulator of angiogenesis. The aim of this study was to evaluate the role of serum VEGF as a diagnostic, predictive and prognostic marker in Ewing’s sarcoma.

Methods

Patients with histopathologically proven diagnosis of Ewing’s sarcoma without prior chemotherapy or radiotherapy were invited to take part in the study. Pre-chemotherapy, post-chemotherapy and post-surgery blood samples were collected for analysis of serum VEGF levels. Blood samples from ten sex- and age-matched healthy volunteers were collected for estimation of VEGF levels to act as control. Human VEGF Elisa kit (Bender Medsystem, Austria) was used to assess the serum VEGF levels.

Results

A total of nine cases of Ewing’s sarcoma were included in the study. Mean age in the group was 12.44 years (range, seven to 18 years). Mean and median serums VEGF level in the study population were 4,547.78 pg/ml and 3,780.00 pg/ml, respectively. Ten age- and sex-matched healthy volunteers were selected as controls. No significant correlation was obtained between serum VEGF, age, sex and tumour size. Mean serum VEGF was significantly raised in the study group as compared to controls (p = 0.001). We observed a significant decline in serum VEGF level following neoadjuvant chemotherapy (p = 0.008). No correlation could be established between serum VEGF level pulmonary metastasis and overall survival.

Conclusion

Serum VEGF might have a role as a diagnostic and predictive marker in patients with Ewing’s sarcoma.  相似文献   
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