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21.
The effect of smoking on bicarbonate and volume of duodenal juice was studied. It was found that in the basal condition smoking produced significant decreases in bicarbonate content and volume of duodenal samples. On the contrary, during pancreatic stimulation with secretin at approximately 50% of maximal secretion, smoking resulted in significant increases in bicarbonate output and volume. Decrease in buffering power of duodenal juice in the basal condition can, at least partially, explain the causative relation of smoking and peptic ulcer disease.Supported in part by Ayerst Laboratories, New York.Boots Secretin was kindly donated by Dr. K. Cartwright of Boots Pure Drug Co. Ltd., Nottingham, England.  相似文献   
22.
The treatment of adults with Philadelphia-negative acute lymphoblastic leukaemia (ALL) depends on the presence of risk factors including age, white blood cell count, immunophenotype and time to complete remission. In recent years, status of minimal residual disease (MRD) has been postulated as an additional risk criterion. This study prospectively evaluated the significance of MRD. Patients were treated with a uniform Polish Adult Leukemia Group (PALG) 4-2002 protocol. MRD status was assessed after induction and consolidation by multiparametric flow cytometry. Out of 132 patients included (age, 17–60 years), 116 patients were suitable for analysis. MRD level ≥0·1% of bone marrow cells after induction was found to be a strong and independent predictor for relapse in the whole study population ( P  < 0·0001), as well as in the standard risk (SR, P  = 0·0003) and high-risk ( P  = 0·008) groups. The impact of MRD after consolidation on outcome was not significant. The combination of MRD status with conventional risk stratification system identified a subgroup of patients allocated to the SR group with MRD <0·1% after induction who had a very low risk of relapse of 9% at 3 years as opposed to 71% in the remaining subjects ( P  = 0·001). We conclude that MRD evaluation after induction should be considered with conventional risk criteria for treatment decisions in adult ALL.  相似文献   
23.
Objective:To compare the efficacy and tolerance of 7-days-a-week accelerated postoperative radiotherapy (p-CAIR) vs postoperative radio-chemotherapy (p-RTCT)Methods:Between September 2007 and October 2013, 111 patients were enrolled and randomly assigned to receive 63 Gy in 1.8 Gy fractions 7-days-a-week (n = 57, p-CAIR) or 63 Gy in 1.8 Gy fractions 5-days-a-week with concurrent cisplatin 80–100 mg per square meter of body-surface area on days 1, 22 and 43 of the radiotherapy course (p-RTCT). It represents approximately 40% of the intended trial size, that was closed prematurely due to slowing accrual. Only high-risk patients with squamous cell cancer of the oropharynx/oral cavity, considered fit for concurrent treatment were enrolled.Results:The rate of locoregional control (LRC) did not differ significantly between treatment arms (p = 0.18, HR = 0.56), 5 year LRC tended, however, to favour p-RTCT (81%) vs p-CAIR (62%). There was no difference in overall survival between treatment arms (p = 0.90, HR = 1.03).The incidence and severity of acute mucosal reactions and late reactions did not differ significantly between treatment arms. Haematological toxicity of p-RTCT was, however, considerably increased compared to p-CAIRConclusion:Concurrent postoperative RTCT tended to improve locoregional control rate as compared to p-CAIR. This, however, did not transferred into improved overall survival. Postoperative RTCT was associated with a substantial increase in haematological toxicity that negatively affected treatment compliance in this arm.Advances in knowledge:To our knowledge, this is the first trial that compares accelerated radiotherapy and radio-chemotherapy in postoperative treatment for oralcavity/oropharyngeal cancer  相似文献   
24.
In this paper, we describe the role of anatase and rutile crystal phases on diphenyl sulphide (Ph2S) catalytic and photocatalytic oxidation. The highly selective and efficient synthesis of diphenyl sulfoxide (Ph2SO) and diphenyl sulfone (Ph2SO2) at titanium dioxide was demonstrated. Ph2S oxidation in the presence of hydrogen peroxide at anatase-TiO2 can take place both as a catalytic and photocatalytic reaction, while at rutile-TiO2 only photocatalytic oxidation is possible. The reaction at anatase leads mainly to Ph2SO2, whereas, in the presence of rutile a complete conversion to Ph2SO is achieved after only 15 min (nearly 100% selectivity). Studies on the mechanistic details revealed a dual role of H2O2. It acts as a substrate in the reaction catalysed only by anatase, but it also plays a key role in alternative photocatalytic oxidation pathways. The presented study shows the applicability of photocatalysis in efficient and selective sulfoxide and sulfone production.

Selective sulfoxide and sulfone production can be precisely controlled by choosing TiO2 polymorph and the reaction mode (catalysis versus photocatalysis).  相似文献   
25.
Fecal microbiota transplantation (FMT) was performed to decolonize gastrointestinal tract from antibiotic‐resistant bacteria before allogeneic hematopoietic cells transplantation (alloHCT). AlloHCT was complicated by norovirus gastroenteritis, acute graft‐versus‐host disease, and eosinophilic pancolitis. Norovirus was identified in samples from FMT material. Symptoms resolved after steroids course and second norovirus‐free FMT from another donor.  相似文献   
26.
Multiferroic solid solutions of Ba1−xLaxTi1−x/4O3 and iron (BLFT) were synthesized using the conventional mixed oxide method. The dependence of the piezoelectric coefficients on Fe content in BLFT ceramics was determined by the quasi-static and resonance method. The results indicate that 0.3 mol% addition of Fe3+ ions to the ceramic structure increased the value of the piezoelectric parameter d33 to the maximum of 159 pC/N. This puts BLFT ceramics among other good-quality and lead-free piezoelectric ceramics. A major enhancement of dielectric properties related to the manipulation of Fe content in the barium lanthanum titanate (BLT) ceramics system is reported as well.  相似文献   
27.
28.
Jedrychowski W, Perera FP, Jankowski J, Maugeri U, Mrozek‐Budzyn D, Mroz E, Flak E, Skarupa A, Edwards S, Lisowska‐Miszczyk I. Early wheezing phenotypes and cognitive development of 3‐yr‐olds. Community‐recruited birth cohort study.
Pediatr Allergy Immunol 2010: 21: 550–556.
© 2009 John Wiley & Sons A/S The main purpose of the study was to answer the question whether young children without clinical diagnosis of asthma but experiencing early wheezing disorders and therefore being at high risk of developing asthma may have cognitive deficits. In the ongoing birth cohort study wheezing symptoms were recorded postpartum over two first years of age and subsequently cognitive status of children at the age of 3 yr was assessed with the Bayley Mental Development Index (MDI). In the statistical analysis a wide range of modifying and confounding factors (maternal education, gender of children, prenatal exposure to lead and environmental tobacco smoke (ETS) were considered to assess the independent effect of early wheezing phenotypes on cognitive development of children. The MDI score correlated inversely with the number of wheezing days recorded over 24 months (r = ?0.13, p = 0.007), lead cord blood concentration (r = ?0.12, p = ?0.02), number of siblings (r = ?0.17, p = 0.0006) and the number of cigarettes smoked daily by other household members at home over the pregnancy period (r = ?0.18, p = 0.0002). While the children who experienced wheezing over the first year of age showed deficit of 2 MDI scores (beta coeff. = ?2.31, 95%CI: ?4.63 to 0.02), those with persistent wheezing had the score deficit of 4 points (beta coeff. = ?4.41, 95%CI: ?8.27 to ?0.55). To our knowledge, it is the first report in the iterature showing that early wheezing is associated the cognitive deficit in a community‐recruited very young children. Observed cognitive deficit in early wheezers may be caused by RSV infections or can be related to lower lung function attributed to persistent wheezing, which reducing oxygen supply would affect rapidly developing brain.  相似文献   
29.
Under normal physiological conditions, gastric acid production is controlled by a negative feedback mechanism. Proton pump inhibitors, such as pantoprazole, inhibit gastric acid secretion by irreversibly binding and inactivating luminally active hydrogen potassium ATPase. Recovery of acid production after treatment with a proton pump inhibitor is driven by new pump synthesis, activation of existing cytoplasmic pumps, or reversal of proton pump inhibition. The authors measured the time course of the inhibition and recovery of acid secretion in healthy volunteers following intravenous administration of pantoprazole to determine the rate of proton pump activation under maximally stimulated conditions. Gastric acid production was measured in 27 Helicobacter pylori negative healthy volunteers (mean age = 31 +/- 7 years; 17 men, 10 women) who received single doses of intravenous pantoprazole (20, 40, 80, or 120 mg) in the presence of a continuous intravenous infusion of 1 ug/kg/h of pentagastrin. From the time profile of acid secretion, the authors described the rate of change of acid output using an irreversible pharmacodynamic response model represented by the equation dR/dt = -k x R x Cpanto + Ln2/PPR x (Ro-R) and correlated the parameter values with demographic factors and gastric acid measurements. Mean stimulated acid output secretion was 21.6 +/- 18.4 mEq/h (range: 1.6-90.5) prior to the administration of pantoprazole and remained steady for 25 hours after placebo administration. Intravenous pantoprazole inhibited acid output in a dose-response fashion, with maximal inhibition (99.9%) occurring after an 80 mg dose. Mean proton pump recovery time was 37.1 +/- 21.0 hours (range: 6.7-75), and recovery was independent of the dose of pantoprazole. There was no association noted between proton pump recovery time and gender, age, race, body weight, or pantoprazole dose. However, there was an inverse correlation between acid output during baseline stimulation and recovery of acid secretion. Mean proton pump recovery time in stimulated normal human volunteers was 37.1 +/- 21.0 hours, with a range of 6.7 to 75 hours. The authors hypothesize that there may be a normal homeostatic mechanism that maintains acid secretory capability within a normal range by altering the rate of proton pump activation dependent on the individual's parietal cell mass. Abnormalities of this process may be responsible for the development of acid peptic disease in susceptible individuals.  相似文献   
30.
Exposure to multiple physical and chemical agents is common in occupational environments but workplace hazards and occupational safety criteria for combined exposures is lacking. NoiseChem is an European Commission research project examining the effects of exposure to noise and chemicals on hearing and balance. Partners in Sweden, Finland, France, Denmark, UK and Poland with expert guidance from partners in USA will examine workers and study the mechanisms of action in animals to determine the levels of risk associated with joint exposure to noise and solvents. This paper briefly outlines the project details.  相似文献   
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