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Gravier R  Dory D  Laurentie M  Bougeard S  Cariolet R  Jestin A 《Vaccine》2007,25(39-40):6930-6938
Previous biodistribution studies of plasmids following intramuscular or intradermal injections of DNA vaccines have been performed in mice, rats or rabbits, but not in large mammals. The aim of the present study was to determine the biodistribution of plasmids in swine using the PRV-specific DNA vaccination model consisting of a single intramuscular (i.m.) injection of three plasmids individually encoding glycoproteins gB, gC and gD. The weak bioavailability of the plasmids (less than 10%) after i.m. injection was consistent with the tissue distribution study. Plasmids remained in the injected muscle for at least 4 weeks and were also detected in liver, spleen, kidney, lung, remote muscle, lymph nodes and ovaries for shorter periods. Differences in persistence, apparent elimination half-lives and clearance in blood were observed between the three plasmids. In conclusion, the three plasmids behaved differently and were transiently detected in most of the organs tested. The exact persistence in the injected muscle was not determined but exceeded 4 weeks. To date this is the first published DNA vaccine tissue distribution study in large animals.  相似文献   
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Semi-opaque to opaque films containing small amounts of various aluminium particles to decrease emissivity were easily prepared and coated onto low-density polyethylene (LDPE) sheets. The thermal-radiative properties (reflectivity, transmissivity and absorptivity) of the films were measured and related to the aluminum particles’ content, size and nature. Time-to-ignition of samples was assessed using a cone calorimeter at different heat flux values (35, 50 and 75 kW/m2). The coatings allowed significant ignition delay and, in some cases, changed the material behaviour from thermally thin to thick behaviour. These effects are related both to their emissivity and transmissivity. A lower emissivity, which decreases during the degradation, and a lower transmissivity are the key points to ensure an optimal reaction-to-fire.  相似文献   
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Articular cartilage presents a poor capacity for self-repair. Its structure-function are frequently disrupted or damaged upon physical trauma or osteoarthritis in humans. Similar musculoskeletal disorders also affect horses and are the leading cause of poor performance or early retirement of sport- and racehorses. To develop a therapeutic solution for horses, we tested the autologous chondrocyte implantation technique developed on human bone marrow (BM) mesenchymal stem cells (MSCs) on horse BM-MSCs. This technique involves BM-MSC chondrogenesis using a combinatory approach based on the association of 3D–culture in collagen sponges, under hypoxia in the presence of chondrogenic factors (BMP-2 + TGF-β1) and siRNA to knockdown collagen I and HtrA1. Horse BM-MSCs were characterized before being cultured in chondrogenic conditions to find the best combination to enhance, stabilize, the chondrocyte phenotype. Our results show a very high proliferation of MSCs and these cells satisfy the criteria defining stem cells (pluripotency-surface markers expression). The combination of BMP-2 + TGF-β1 strongly induces the chondrogenic differentiation of MSCs and prevents HtrA1 expression. siRNAs targeting Col1a1 and Htra1 were functionally validated. Ultimately, the combined use of specific culture conditions defined here with specific growth factors and a Col1a1 siRNAs (50 nM) association leads to the in vitro synthesis of a hyaline-type neocartilage whose chondrocytes present an optimal phenotypic index similar to that of healthy, differentiated chondrocytes. Our results lead the way to setting up pre-clinical trials in horses to better understand the reaction of neocartilage substitute and to carry out a proof-of-concept of this therapeutic strategy on a large animal model.  相似文献   
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We have previously shown that serotonin (5-HT) stimulates aldosterone secretion from the human adrenal gland through activation of 5-HT(4) receptors. The aim of the present study was to investigate in vivo and in vitro the presence of 5-HT(4) receptors in aldosterone-producing adenomas (aldosteronomas). Eight patients with aldosteronoma received a single oral dose of placebo or cisapride (10 mg). Cisapride administration significantly increased plasma aldosterone within 120 min without any significant change in renin, cortisol, or potassium levels. In two patients, a marked decrease in the plasma aldosterone response to cisapride was observed after surgical removal of the tumor. The effects of 5-HT and selective 5-HT(4) ligands on aldosterone production from aldosteronoma tissues were studied in vitro using a perifusion system technique. 5-HT and the 5-HT(4) receptor agonist cisapride (10(-7) M, 20 min) both stimulated aldosterone secretion from aldosteronoma slices. The 5-HT- and cisapride-evoked aldosterone responses were inhibited by concomitant administration of the specific 5-HT(4) receptor antagonist GR 113808 (10(-7) M, 150 min). PCR amplification revealed the expression of 5-HT(4) receptor mRNA in 13 of 14 aldosteronomas studied. Taken together, these data show that most aldosteronomas, like normal glomerulosa cells, express a functional 5-HT(4) receptor. Our results also suggest that 5-HT, which can be locally released by intratumoral mast cells, may play a role in the pathophysiology of these tumors.  相似文献   
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Study Type – Therapy (case series) Level of Evidence 4 What's known on the subject? and What does the study add? To date, there is controversy about the impact of histological subtype of bladder cancer (nonbilharzial squanous cell carcinoma vs. urothelial carcinoma) on cancer control outcomes. Our study shows that the histological subtype may have an impact on the stage of bladder cancer at presentation. However, after adjusting to stage, the histological subtype has no impact on cancer control outcomes.

OBJECTIVES

  • ? To test the effect of histological subtype (NBSCC vs UC) on cancer‐specific mortality (CSM), after adjusting for other‐cause mortality (OCM).
  • ? In Western countries, non‐bilharzial squamous cell carcinoma (NBSCC) is the second most common histological subtype in bladder cancer (BCa) after urothelial carcinoma (UC).

PATIENTS AND METHODS

  • ? We identified 12 311 patients who were treated with radical cystectomy (RC) between 1988 and 2006, within 17 Surveillance, Epidemiology and End Results (SEER) registries.
  • ? Univariable and multivariable competing‐risks analyses tested the relationship between histological subtype and CSM, after accounting for OCM.
  • ? Covariates consisted of age, sex, year of surgery, race, pathological T and N stages, as well as tumour grade.

RESULTS

  • ? Histological subtype was NBSCC in 614 (5%) patients vs UC in 11 697 (95%) patients.
  • ? At RC, the rate of non‐organ confined (NOC) BCa was higher in NBSCC patients than in their UC counterparts (71.7% vs 52.2%; P < 0.001).
  • ? After adjustment for OCM, The 5‐year cumulative CSM rates were 25.0% vs 19.8% (P= 0.2) for patients with NBSCC vs UC organ confined (OC) BCa, respectively. The same rates were 46.3% vs 49.3% in patients with NOC BCa (P= 0.1).
  • ? In multivariable competing‐risks analyses, histological subtype (NBSCC vs UC) failed to achieve independent predictor status of CSM in patients with OC (hazard ratio, 1.2; P= 0.06) or NOC BCa (hazard ratio, 1.1; P= 0.1).

CONCLUSIONS

  • ? At RC, the rate of NOC BCa is higher in NBSCC patients than in their UC counterparts.
  • ? Despite a more advanced stage at surgery, NBSCC histological subtype is not associated with a less favourable CSM than UC histological subtype, after accounting for OCM and the extent of the disease (OC vs NOC).
  相似文献   
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