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21.
Julia C. Schmidt Monika Astasov-Frauenhoffer Irmgard Hauser-Gerspach Jan-Philipp Schmidt Tuomas Waltimo Roland Weiger Clemens Walter 《Clinical oral investigations》2014,18(3):793-800
Objectives
The aim of this study was to evaluate the efficacy of four different powered toothbrushes with side-to-side action for noncontact biofilm removal in vitro.Materials and methods
A three-species biofilm was formed in vitro on protein-coated titanium disks using a flow chamber combined with a static biofilm growth model. Subsequently, the biofilm-coated substrates were exposed to four different side-to-side toothbrushes (A, B, C, and D) with various brushing times (2, 4, and 6 s) and brushing (bristle-to-disk) distances (0, 2, and 4 mm). The biofilm volumes were measured using volumetric analyses with confocal laser scanning microscope images and Imaris version 7.5.2 software.Results
The median percentages of biofilm reduction by the analyzed toothbrushes ranged from 9 % to 80 %. The abilities of the tested toothbrushes to remove the in vitro biofilm differed significantly (p?<?0.05). Two of the tested toothbrushes (C and D) were capable of significant biofilm reduction by noncontact brushing.Conclusions
It was possible to reduce a three-species in vitro biofilm by noncontact brushing with two out of four side-to-side toothbrushes.Clinical relevance
Toothbrushes C and D show in vitro a high efficacy in biofilm removal without bristle contact. 相似文献22.
C. Schmidt M. Fronza M. Goettert F. Geller S. Luik E.M.M. Flores C.F. Bittencourt G.D. Zanetti B.M. Heinzmann S. Laufer I. Merfort 《Journal of ethnopharmacology》2009
Aim of the study
n-Hexanic and ethanolic extracts from twelve plants (Brugmansia suaveolens Brecht. et Presl., Eupatorium laevigatum Lam., Galinsoga parviflora Cav., Iresine herbstii Hook., Kalanchöe tubiflora Hamet-Ahti, Petiveria alliacea L., Pluchea sagittalis (Lam.) Cabrera, Piper regnellii DC., Schinus molle L., Sedum dendroideum Moç et Sessé ex DC., Waltheria douradinha St. Hill., Xanthium cavanillesii Schouw.) used in traditional South Brazilian medicine as wound healing agents were investigated in various biological assays, targeting different aspects in this complex process.Materials and methods
The extracts were investigated on NF-κB DNA binding, p38α MAPK, TNF-α release, direct elastase inhibition and its release as well as on caspase-3. Fibroblasts migration to and proliferation into the wounded monolayers were evaluated in the scratch assay, the agar diffusion test for antibacterial and the MTT assay for cytotoxic effects.Results
The hydrophilic extracts from Galinsoga parviflora, Petiveria alliacea, Schinus molle, Waltheria douradinha and Xanthium cavanillesii as well as the lipophilic extract of Waltheria douradinha turned out to be the most active ones.Conclusions
These results increase our knowledge on the wound healing effects of the investigated medicinal plants. Further studies are necessary to find out the effective secondary metabolites responsible for the observed effects. 相似文献23.
Steffen Wagner Abraham Ureña Eike Reich Irmgard Merfort 《Journal of pharmaceutical and biomedical analysis》2008
Preparations of Harpagophytum procumbens and of Salix species are successfully used for the treatment of degenerative rheumatism and painful arthrosis. For the quality control of both drugs, rapid methods of quantification are desirable. Here we report the development of two HPTLC methods enabling the determination of harpagoside in Harpagophyti radix and of salicin in Salicis cortex. We focused on a standardized methodology and thorough validation including two laboratories. The methods allow the analyses of up to 16 samples in parallel demonstrating the proposed methods as very rapid and cost efficient. 相似文献
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In order to investigate the mechanism of kinin release leading to vascular symptoms in acute interstitial-oedematous pancreatitis, the novel, selective inhibitors of tissue kallikrein, (2S,2'R)-2-(2'-amino-3'-(4'-chlorophenyl)propanoylamino)-N-(3-guanidinopropyl)-3-(1-naphthyl)propanoamide (FE999024, CH-2856), and of plasma kallikrein, (2'S,2"R)-4-(2'-(2"(carboxymethylamino)-3"-cyclohexyl-propanoylamino)-3'-phenyl-propanoylamino)piperidine-1-carboxamidin (FE999026, CH-4215), were used in experimental caerulein-induced pancreatitis in rats. Oedema formation and plasma protein extravasation during the 2 h infusion of caerulein were inhibited in a dose-dependent manner by i.p. pretreatment with FE999024 (7-60 micromol kg(-1)) while FE999026 had no effect at the same doses. Haemoconcentration and hypovolaemia associated with the pancreatic oedema formation during pancreatitis were significantly attenuated by FE999024 at a dose of 20 micro mol kg(-1). The reduction in circulating plasma volume was not affected by FE999026. Accumulation of amylase and lipase in the pancreas was dose-dependently reduced by FE999024 while enzyme activities in the blood serum were increased by FE999024 at 60 micromol kg(-1) indicating improved enzyme removal from the tissue. Enzyme activities in the tissue and in the blood remained unaffected by FE999026. FE999024 (20 micromol kg(-1)) largely inhibited increased tissue kallikrein-like activity in the pancreas during acute pancreatitis and also strongly attenuated influx of plasma kallikrein into the tissue. FE999026 (20 micromol kg(-1)) significantly inhibited plasma kallikrein-like activity in the pancreas but had no effect on tissue kallikrein-like activity. In conclusion, vascular kinin-mediated symptoms observed during oedematous pancreatitis in the rat are caused by the action of tissue kallikrein in the pancreas whereas an involvement of plasma kallikrein seems to be unlikely. 相似文献
26.
Tauber E Fazekas T Eichler I Eichstill C Gartner C Koller DY Frischer T 《Pediatric pulmonology》2003,35(3):162-168
The negative expiratory pressure technique (NEP) has been applied in adults with chronic obstructive pulmonary disease (COPD), demonstrating flow limitation in many of these patients. Because this technique does not require patient cooperation, it is of potential interest for application in the pediatric population. This study was performed to test the feasibility of NEP in children, and to further investigate it in children with asthma and cystic fibrosis (CF). We performed NEP (0.3-0.7 kPa) measurements in 14 healthy children (13.3 years, +/- 2.4), in 12 children with asthma (11.7 years, +/- 3.0), and in 17 children with CF (13.3 years, +/- 2.7). NEP-derived flow-volume loops were visually analyzed for flow limitation at tidal breathing. In addition, expiratory flow at 50% of tidal volume (TEF(50)) was measured. In healthy children, the intraclass coefficient of correlation was 77%, and intraindividual short- and long-term variability was 5.8% and 10.8%, respectively. In asthmatics, TEF(50) was lower compared with controls, and increased after inhalation of salbutamol. However, appropriate size-correction has still to be established. Measurement of TEF(50) using NEP is feasible in children. Despite good reproducibility in individual patients, the high intersubject variability may limit its usefulness as a clinical tool. In addition, the lack of flow limitation using NEP even in severely obstructed patients with CF warrants further investigation. 相似文献
27.
Röckl-Wiedmann I Meyer N Fischer R Laubereau B Weitkunat R Uberla K 《Sozial- und Pr?ventivmedizin》2002,47(5):307-317
OBJECTIVES: This article aims to analyse utilisation of medical services and screening programmes in relation to social class. METHODS: 2051 adults in Bavaria were interviewed using computer-assisted telephone interview (CATI) in 1999/2000. Social class was established from the income-adjusted Winkler social category index. Data were standardised by age and sex. If social class differences were found, separate analyses for education and income effects were conducted. RESULTS: Higher education was found to be associated with visits to specialist and vaccinations. The purchase of over-the-counter medication was related to higher education and family income. Frequency of HIV-tests was higher in higher social classes but not related to higher education or better financial situation. Utilisation rates for screening programmes for various types of cancer were similar in all social classes. CONCLUSIONS: The results show that social class differences in health behaviour in Bavaria prevail. Positive health behaviour is often associated with higher education. Compared to earlier findings social class effects on the utilisation of cancer screening appears less pronounced. Preventive measures seem to have reached all social classes to a similar degree. 相似文献
28.
Smad4 induces the tumor suppressor E-cadherin and P-cadherin in colon carcinoma cells 总被引:14,自引:0,他引:14
Müller N Reinacher-Schick A Baldus S van Hengel J Berx G Baar A van Roy F Schmiegel W Schwarte-Waldhoff I 《Oncogene》2002,21(39):6049-6058
29.
Jiyoung Ahn Christine B Ambrosone Peter A Kanetsky Chunqiao Tian Teresa A Lehman Silke Kropp Irmgard Helmbold Dietrich von Fournier Wulf Haase Marie Luise Sautter-Bihl Frederik Wenz Jenny Chang-Claude 《Clinical cancer research》2006,12(23):7063-7070
PURPOSE: Because radiotherapy exerts cytotoxic effects via generation of massive oxidative stress, we hypothesized that catalase, manganese superoxide dismutase, myeloperoxidase (MPO), and endothelial nitric oxide synthase (eNOS) genotypes might result in greater risk of radiotoxicity. EXPERIMENTAL DESIGN: Cases (n = 446) were Caucasian women with breast cancer who received radiotherapy following lumpectomy. Genotypes were determined by matrix-assisted laser desorption/ionization time-of-flight. The development of acute reactions (moist desquamation) associated with genotypes was modeled using the Cox proportional hazards model, accounting for cumulative biologically effective radiation dose. RESULTS: Genotypes associated with higher levels of reactive oxygen species (ROS) were not associated with risk of radiotoxicity. However, relationships between overweight/obesity [body mass index (BMI), >25] and radiotoxicity risk seemed to be modified by eNOS and MPO genotypes associated with higher generation of nitric oxide and ROS, respectively. Women with high BMI (>25) and eNOS GG genotypes were at more than a 6-fold increase in risk (hazard ratio, 6.39; 95% confidence interval, 2.53-16.15) compared with those with BMI <25, and for MPO, those with high BMI (>25) and GG genotypes also had greater risk of radiotoxicity (hazard ratio, 3.61; 95% confidence interval, 1.78-7.35) compared with those with BMI <25. Overweight/obesity was not a strong risk factor among women with other eNOS and MPO genotypes. Exploratory analysis using classification and regression trees indicated that total number of risk alleles contributed, in part, to acute toxicity outcomes among a subgroup of women. CONCLUSIONS: Associations between BMI and radiotoxicity risk may be most apparent among women with genotypes related to higher levels of oxidative stress. Regression trees may be useful in future studies to examine the contributions of multiple factors to individual susceptibility to adverse effects of cancer treatment. 相似文献
30.