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31.
The protective effect of salbutamol inhaled using different devices on methacholine bronchoconstriction 总被引:2,自引:0,他引:2
Giannini D Di Franco A Bacci E Dente FL Taccola M Vagaggini B Paggiaro P 《Chest》2000,117(5):1319-1323
STUDY OBJECTIVE: To determine the protective effect of salbutamol, 100 microg, inhaled by different devices (pressurized metered-dose inhaler [pMDI; Ventolin; GlaxoWellcome; Greenford, UK], pMDI + spacer [Volumatic; GlaxoWellcome], or breath-activated pMDI [Autohaler; 3M Pharmaceuticals; St. Paul, MN]) on bronchoconstriction induced by methacholine. DESIGN: Randomized, double-blind, cross-over, placebo-controlled study. PATIENTS: Eighteen subjects with stable, moderate asthma, asymptomatic, receiving regular treatment with salmeterol, 50 microg bid, and inhaled beclomethasone dipropionate, 250 microg bid, in the last 6 months, with high hyperreactivity to methacholine (baseline provocative dose of methacholine causing a 20% fall in FEV(1) [PD(20)] geometric mean [GM], 0.071 mg). Subjects were classified into two groups: subjects with incorrect (n = 5) pMDI inhalation technique, and subjects with correct (n = 13) inhalation technique. METHODS AND MEASUREMENTS: After cessation of therapy for 3 days, all subjects underwent four methacholine challenge tests, each test 1 week apart, each time 15 min after inhalation of salbutamol, 100 microg (via pMDI, pMDI + spacer, or Autohaler), or placebo. The protective effect on methacholine challenge test was evaluated as the change in the PD(20), and expressed in terms of doubling doses of methacholine in comparison with placebo treatment. RESULTS: The PD(20) was significantly higher after salbutamol inhalation than after placebo inhalation, but no significant difference was observed among the three different inhalation techniques. Only when salbutamol was inhaled via pMDI + spacer, PD(20) was slightly but not significantly higher (pMDI GM, 0.454 mg; pMDI + spacer GM, 0.559 mg; and Autohaler GM, 0.372 mg; not significant [NS]) than other inhalation techniques. Similar results (mean +/-SEM) were obtained with doubling doses of methacholine (pMDI, 2 +/- 0.47; pMDI + spacer, 3 +/- 0.35; and Autohaler, 2.4 +/- 0.40; NS). No significant difference was found among techniques when subjects with correct or incorrect inhalation technique were separately considered. CONCLUSIONS: Our data show that the protective effect of salbutamol, 100 microg, on methacholine-induced bronchoconstriction is not affected by the different inhalation techniques, although inhalation via pMDI + spacer tends to improve the bronchoprotective ability of salbutamol. These data confirm the clinical efficacy of salbutamol, whatever the device, and the patient's inhalation technique. 相似文献
32.
Pier Pasquale Leone Damiano Regazzoli Matteo Pagnesi Jorge Sanz-Sanchez Mauro Chiarito Francesco Cannata Nicolas M. Van Mieghem Marco Barbanti Corrado Tamburino Rui Teles Marianna Adamo Mizuki Miura Francesco Maisano Won-Keun Kim Francesco Bedogni Giulio Stefanini Antonio Mangieri Francesco Giannini Azeem Latib 《JACC: Cardiovascular Interventions》2021,14(11):1218-1228
ObjectivesThe aim of this study was to define predictors of prosthesis-patient mismatch (PPM) and its impact on mortality after transcatheter aortic valve replacement (TAVR) with self-expandable valves (SEVs) in patients with small annuli.BackgroundTAVR seems to reduce the risk for PPM compared with surgical aortic valve replacement, especially in patients with small aortic annuli. Nevertheless, predictors and impact of PPM in this population have not been clarified yet.MethodsPredictors of PPM and all-cause mortality were investigated using multivariable logistic regression analysis from the cohort of the TAVI-SMALL (International Multicenter Registry to Evaluate the Performance of Self-Expandable Valves in Small Aortic Annuli) registry, which included patients with severe aortic stenosis and small annuli (annular perimeter <72 mm or area <400 mm2 on computed tomography) treated with transcatheter SEVs: 445 patients with (n = 129) and without (n = 316) PPM were enrolled.ResultsIntra-annular valves conferred increased risk for PPM (odds ratio [OR]: 2.36; 95% confidence interval [CI]: 1.16 to 4.81), while post-dilation (OR: 0.46; 95% CI: 0.25–0.84) and valve oversizing (OR: 0.53; 95% CI: 0.28–1.00) seemed to protect against PPM occurrence. At a median follow-up of 354 days, patients with severe PPM, but not those with moderate PPM, had a higher all-cause mortality rate compared with those without PPM (log-rank p = 0.008). Multivariable Cox regression confirmed severe PPM as an independent predictor of all-cause mortality (hazard ratio: 4.27; 95% CI: 1.34 to 13.6).ConclusionsAmong patients with aortic stenosis and small aortic annuli undergoing transcatheter SEV implantation, use of intra-annular valves yielded higher risk for PPM; conversely, post-dilation and valve oversizing protected against PPM occurrence. Severe PPM was independently associated with all-cause mortality. 相似文献
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Histomorphometry or quantitative histology is the analysis on histologic sections of bone resorption parameters, formation and structure. It is the only technique that allows a dynamic evaluation of the activity of bone modelling after labelling with tetracycline. Moreover, the new measurement procedures through the use of the computer allow an assessment of bone microarchitecture too. Histomorphometric bone biopsy is a reliable and well-tolerated procedure. Complications are reported only in 1% of the subjects (hematoma, pain, transient neuralgia). Histomorphometry is used to exclude or confirm the diagnosis of osteomalacia. It is employed in the evaluation of bone damage associated with particular treatments (for example, anticonvulsants) or in case of rare bone diseases (osteogenesis imperfecta, systemic mastocytosis). It is also an essential approach when clinical, biochemical and other diagnostic data are not consistent. Finally, it is a useful method to understand the pathophysiologic mechanisms of drugs. The bone sample is taken at the level of iliac crest under local anesthesia. It is then put into methyl-metacrilate resin where the sections are prepared for the microscopic analysis of the various histomorphometric parameters. 相似文献
36.
Calò L Castrignano R Davis PA Carraro G Pagnin E Giannini S Semplicini A D'Angelo A 《Journal of endocrinological investigation》2000,23(4):223-227
Osteoporosis is characterized by impairment of bone mass and deterioration of bone microscopic structure, resulting in increased bone fragility and susceptibility to fracture. Recent reports have indicated that reduced plasma levels of IGF-I are associated with osteoporosis in both males and females. Moreover, there is accumulating clinical evidence that treatment with GH or IGF-I has beneficial effects on bone mass and bone remodeling in men with idiopathic osteoporosis, in the elderly and in hypopituitary patients. As correlative studies on IGF-I, IGF-BP3 and bone mass in the elderly are lacking, we studied the relationships between serum IGF-I, IGF-BP3, bone mineral density (BMD), body mass index (BMI), calciotropic hormones and age in 102 premenopausal and postmenopausal women. Our study indicates that the reduction of the anabolic processes mediated by IGF-I may account for the slow and progressive loss of bone mass that take place after the age of 40-50 years. In addition, nutritional caloric or proteic deficit may add to the effects of GH, age and other factors in decreasing IGF-I synthesis and therefore further contribute to the development of primary osteoporosis. 相似文献
37.
The mechanisms underlying the impaired utilization of transferrin-bound iron by erythroid cells in the anemia of the Belgrade laboratory rat were investigated using reticulocytes from homozygous anemic animals and transferrin labeled with 59Fe and 125I. The results were compared with those obtained using reticulocytes from phenylhydrazine-treated rats and iron-deficient rats. Each step in the iron uptake mechanism was investigated, ie, transferrin-receptor interaction, transferrin endocytosis, iron release from transferrin, and transferrin exocytosis. Although there were quantitative differences, no fundamental difference was found in any of the abovementioned aspects of cellular function when the reticulocytes from Belgrade rats were compared with those from iron-deficient animals. The basic defect in the Belgrade reticulocytes must therefore reside in subsequent steps in iron uptake, after it is released from transferrin within endocytotic vesicles, ie, in the mechanism by which it is transferred across the lining membrane of the vesicles into the cell cytosol. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of reticulocyte ghosts extracts demonstrated a prominent protein band of mol wt 69,000 that was absent or present only in low concentration extracts from the other two types of reticulocytes. This may be a result of the genetic defect. 相似文献
38.
Gabriel Nima Jorge Soto-Montero Lívia A. Alves Renata O. Mattos-Graner Marcelo Giannini 《Dental materials》2021,37(1):e1-e14
ObjectiveThis study aimed to test the efficacy of photodynamic inactivation (PDI) mediated by curcumin with EDTA against Streptococcus mutans in planktonic suspension using blue LED light.MethodsAntibacterial activity of curcumin and EDTA was evaluated by determination of their minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). The fractional inhibitory concentration index (FICI) was used to estimate the synergistic effect of various combination ratios of curcumin and EDTA against S. mutans. Cultures of S. mutans (18 h, 37 °C, 5% C02) were prepared to test the effect of curcumin-mediated PDI (50 μM and 500 μM) with or without 0.4% EDTA and 40 s of light-activation with blue light. EDTA and each concentration of curcumin were also tested individually. Chlorhexidine (0.2%), was used as positive control. Planktonic suspensions were also analyzed by viable colony counts (VCC), confocal laser scanning microscopy (CLSM), transmission electron microscopy (TEM), and polymerase chain reaction (PCR).ResultsThe MIC values of curcumin and EDTA were 5 mM and 0.125% respectively. FICI showed a synergistic interaction between curcumin and EDTA. All the combinations with curcumin and blue LED light resulted in a complete inactivation of the S. mutans and CLSM confirms these results, TEM showed morphological changes produced by the PDI. No damage on DNA structure was detected by PCR.SignificanceCurcumin-mediated PDI with EDTA using a blue light, shows a strong inhibitory effect against S. mutans in planktonic culture. Because of the unspecific target mechanism, it could be a promising technique for disinfection of dental tissues. 相似文献
39.
EH Gemmill DJ Humes JA Catton 《Annals of the Royal College of Surgeons of England》2015,97(3):173-179
Introduction
Fast track methodology or enhanced recovery schemes have gained increasing popularity in perioperative care. While evidence is strong for colorectal surgery, its importance in gastric and oesophageal surgery has yet to be established. This article reviews the evidence of enhanced recovery schemes on outcome for this type of surgery.Methods
A systematic literature search was conducted up to March 2014. Studies were retrieved and analysed using predetermined criteria.Results
From 34 articles reviewed, 18 eligible studies were identified: 7 on gastric and 11 on oesophageal resection. Three randomised controlled trials, five case-controlled studies and ten case series were identified. The reported protocols included changes to each stage of the patient journey from pre to postoperative care. The specific focus following oesophageal resections was on early mobilisation, a reduction in intensive care unit stay, early drain removal and early (or no) contrast swallow studies. Following gastric resections, the emphasis was on reducing epidural anaesthesia along with re-establishing oral intake in the first three postoperative days and early removal of nasogastric tubes.In the papers reviewed, mortality rates following fast track surgery were 0.8% (9/1,075) for oesophageal resection and 0% (0/329) for gastric resection. The reported morbidity rate was 16.5% (54/329) following gastric resection and 38.6% (396/1,075) following oesophageal resection. Length of stay was reduced in both groups compared with conventional recovery groups in comparative studies.Conclusions
The evidence for enhanced recovery schemes following gastric and oesophageal resection is weak, with only three (low volume) published randomised controlled trials. However, the enhanced recovery approach appears safe and may be associated with a reduction in length of stay. 相似文献40.
Autoantibodies against the platelet glycoprotein IIb/IIIa complex in patients with chronic ITP 总被引:21,自引:3,他引:21
Chronic idiopathic thrombocytopenic purpura (ITP) is caused by an antibody reactive with platelet-associated antigens. The present studies provide direct evidence that some patients with chronic ITP have autoantibodies against the platelet glycoprotein (GP) IIb/IIIa complex. Microtiter wells, coated with a monoclonal antibody (2G12) specific for GPIIb/GPIIIa were reacted with GPIIb/GPIIIa contained in a platelet extract. Control wells containing the same antibody were reacted with a cell extract containing no GPIIb/GPIIIa. After washing, the wells were reacted with patient or control plasma, and IgG binding was detected using 125I-Fab2-anti-human IgG. Assay values were expressed as binding ratios (cpm GPIIb/GPIIIa wells/cpm control wells). Plasma from 5 of 56 patients with chronic ITP had ratios (1.36-3.14) greater than 3 standard deviations above the mean (+/- SD) of control plasmas--0.93 +/- 0.12. Elevated values were also noted in two patients with anti-P1A1 antibody (ratios greater than 30) and in one patient with Hodgkin's disease and an ITP-like syndrome (ratio 1.53). Normal values were noted in 34 patients with a variety of immune and nonimmune diseases. Plasma from two of the positive ITP patients was reacted with 125I-surface-labeled platelets and, after solubilization, the IgG and bound antigen were precipitated with Staph-A. Autoradiographs from SDS- PAGE electrophoresis of the Staph-A-bound proteins shows two radioactive bands consistent in size with GPIIb and GPIIIa. 相似文献