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441.
Abhijit Sen  Nikos Papadimitriou  Pagona Lagiou  Aurora Perez-Cornago  Ruth C. Travis  Timothy J. Key  Neil Murphy  Marc Gunter  Heinz Freisling  Ioanna Tzoulaki  David C. Muller  Amanda J. Cross  David S. Lopez  Manuela Bergmann  Heiner Boeing  Christina Bamia  Anastasia Kotanidou  Anna Karakatsani  Anne Tjønneland  Cecilie Kyrø  Malene Outzen  María-Luisa Redondo  Valerie Cayssials  Maria-Dolores Chirlaque  Aurelio Barricarte  Maria-Jose Sánchez  Nerea Larrañaga  Rosario Tumino  Sara Grioni  Domenico Palli  Saverio Caini  Carlotta Sacerdote  Bas Bueno-de-Mesquita  Tilman Kühn  Rudolf Kaaks  Lena Maria Nilsson  Rikard Landberg  Peter Wallström  Isabel Drake  Bodil Hammer Bech  Kim Overvad  Dagfinn Aune  Kay-Tee Khaw  Elio Riboli  Dimitrios Trichopoulos  Antonia Trichopoulou  Konstantinos K. Tsilidis 《International journal of cancer. Journal international du cancer》2019,144(2):240-250
The epidemiological evidence regarding the association of coffee and tea consumption with prostate cancer risk is inconclusive, and few cohort studies have assessed these associations by disease stage and grade. We examined the associations of coffee (total, caffeinated and decaffeinated) and tea intake with prostate cancer risk in the European Prospective Investigation into Cancer and Nutrition. Among 142,196 men, 7,036 incident prostate cancer cases were diagnosed over 14 years of follow-up. Data on coffee and tea consumption were collected through validated country-specific food questionnaires at baseline. We used Cox proportional hazards regression models to compute hazard ratios (HRs) and 95% confidence intervals (CI). Models were stratified by center and age, and adjusted for anthropometric, lifestyle and dietary factors. Median coffee and tea intake were 375 and 106 mL/day, respectively, but large variations existed by country. Comparing the highest (median of 855 mL/day) versus lowest (median of 103 mL/day) consumers of coffee and tea (450 vs. 12 mL/day) the HRs were 1.02 (95% CI, 0.94–1.09) and 0.98 (95% CI, 0.90–1.07) for risk of total prostate cancer and 0.97 (95% CI, 0.79–1.21) and 0.89 (95% CI, 0.70–1.13) for risk of fatal disease, respectively. No evidence of association was seen for consumption of total, caffeinated or decaffeinated coffee or tea and risk of total prostate cancer or cancer by stage, grade or fatality in this large cohort. Further investigations are needed to clarify whether an association exists by different preparations or by concentrations and constituents of these beverages.  相似文献   
442.
Liver mitochondria isolated from rats treated in vivo with trimethyltin chloride show stimulation of respiration using glutamate/malate as substrate, and a transient inhibition on rates of respiration using palmitoyl-L-carnitine as substrate. This phenomenon was observed with both ADP- and FCCP-stimulated respiration. In contrast, rates of respiration by liver mitochondria isolated from rats treated in vivo with trimethyltin chloride, following prior treatment with clofibrate, were inhibited when glutamate/malate was respiratory substrates. With palmitoyl-L-carnitine no effect of trimethyltin chloride was observed. In vitro treatment of rat liver mitochondria, or of rat liver homogenates, led to the expected, powerful inhibition of respiration. The synthesis of ATP by liver mitochondria isolated from rats treated in vivo with trimethyltin chloride was not inhibited compared to mitochondria isolated from control rats. Similarly, ATP synthesis by mitochondria isolated from rats treated with clofibrate, before treatment with trimethyltin chloride, was not inhibited. We, therefore, conclude that the powerful inhibitory effects of trimethyltin found in vitro, is not expressed in vivo during the first 36 hr following administration. In vivo treatment of rats with trimethyltin chloride caused a marked increase in hepatic levels of taurine and glycine, while levels of glutathione and glutamine were diminished. This is consistent with an enhanced oxidative stress in the liver. Our findings lead to the conclusion that increased oxidative stress, rather than inhibition of the mitochondrial ATPase, is a likely major cause of the in vivo toxic effects due to trimethyltin chloride.  相似文献   
443.
Oncogene addiction describes how cancer cells exhibit dependence on single oncogenes to escape apoptosis and senescence. While oncogene addiction constitutes the basis for new cancer treatment strategies targeting individual kinases and pathways activated by oncogenic mutations, the biochemical basis for this addiction is largely unknown. Here we provide evidence for a metabolic rationale behind the addiction to V600EBRAF in two malignant melanoma cell lines. Both cell lines display a striking addiction to glycolysis due to underlying dysfunction of oxidative phosphorylation (OXPHOS). Notably, even minor reductions in glycolytic activity lead to increased OXPHOS activity (reversed Warburg effect), however the mitochondria are unable to sustain ATP production. We show that V600EBRAF upholds the activity of glycolysis and therefore the addiction to glycolysis de facto becomes an addiction to V600EBRAF. Finally, the senescence response associated with inhibition of V600EBRAF is rescued by overexpression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH), providing direct evidence that oncogene addiction rests on a metabolic foundation.  相似文献   
444.
Sabine Naudin  Marta Solans Margalef  Fatemeh Saberi Hosnijeh  Alexandra Nieters  Cecilie Kyrø  Anne Tjønneland  Christina C. Dahm  Kim Overvad  Yahya Mahamat-Saleh  Caroline Besson  Marie-Christine Boutron-Ruault  Tilman Kühn  Federico Canzian  Matthias B. Schulze  Eleni Peppa  Anna Karakatsani  Antonia Trichopoulou  Sabina Sieri  Giovana Masala  Salvatore Panico  Rosario Tumino  Fulvio Ricceri  Sairah L.F. Chen  Leila L. Barroso  José M. Huerta  Maria-Jose Sánchez  Eva Ardanaz  Virginia Menéndez  Pilar Amiano Exezarreta  Florentin Spaeth  Mats Jerkeman  Karin Jirstom  Julie A. Schmidt  Dagfinn Aune  Elisabete Weiderpass  Elio Riboli  Roel Vermeulen  Delphine Casabonne  Marc Gunter  Paul Brennan  Pietro Ferrari 《International journal of cancer. Journal international du cancer》2020,147(6):1649-1656
Limited evidence exists on the role of modifiable lifestyle factors on the risk of lymphoma. In this work, the associations between adherence to healthy lifestyles and risks of Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL) were evaluated in a large-scale European prospective cohort. Within the European Prospective Investigation into Cancer and Nutrition (EPIC), 2,999 incident lymphoma cases (132 HL and 2,746 NHL) were diagnosed among 453,808 participants after 15 years (median) of follow-up. The healthy lifestyle index (HLI) score combined information on smoking, alcohol intake, diet, physical activity and BMI, with large values of HLI expressing adherence to healthy behavior. Cox proportional hazards models were used to estimate lymphoma hazard ratios (HR) and 95% confidence interval (CI). Sensitivity analyses were conducted by excluding, in turn, each lifestyle factor from the HLI score. The HLI was inversely associated with HL, with HR for a 1-standard deviation (SD) increment in the score equal to 0.78 (95% CI: 0.66, 0.94). Sensitivity analyses showed that the association was mainly driven by smoking and marginally by diet. NHL risk was not associated with the HLI, with HRs for a 1-SD increment equal to 0.99 (0.95, 1.03), with no evidence for heterogeneity in the association across NHL subtypes. In the EPIC study, adherence to healthy lifestyles was not associated with overall lymphoma or NHL risk, while an inverse association was observed for HL, although this was largely attributable to smoking. These findings suggest a limited role of lifestyle factors in the etiology of lymphoma subtypes.  相似文献   
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Ethnopharmacological relevance

Roots from Vernonia kotschyana are on the national list of essential drugs in Mali (West-Africa). It is sold under the name Gastrosedal and it used against ailments like gastritis and gastric ulcer. To evaluate the anti-ulcer, immunomodulating activities and toxicity of 50 and 100 °C water extracts, Vk50-I and Vk100-I respectively, from the roots of Vernonia kotschyana.

Materials and methods

Characterization of extracts was carried out by GC, colorimetric and biological methods. Vk50-I and Vk100-I were administrated 50 min before induction of gastric ulcers in mice with 0.3 M HCl–60% EtOH. Inhibition of ulcer formation was calculated based on lesion index. Immunological activities were measured by complement fixation and macrophage activation. Toxicity assay was carried out on brine shrimps.

Results

Vk50-I (98% inulin) and Vk100-I (83% inulin) from Vernonia kotschyana significantly inhibited the formation of gastric lesions in mice (100 mg/kg). No immunomodulating activities or toxicity were found.

Conclusions

Our results show that inulin is probably partly responsible for the anti-ulcer activity of Gastrosedal. In addition, it is possible that water soluble polysaccharides (mainly inulin) have an indirect impact on the general health of the GI.  相似文献   
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Background Cervical cancer screening participation is suboptimal in most settings. We assessed whether human papillomavirus (HPV) self-sampling may increase screening participation among long-term non-attenders in Norway.Methods A pragmatic randomised controlled trial with participation as the primary outcome was initiated in the national cervical screening programme in March 2019. A random sample of 6000 women aged 35–69 years who had not attended screening for at least 10 years were randomised 1:1:1 to receive either (i) a reminder to attend regular screening (control), (ii) an offer to order a self-sampling kit (opt-in) for HPV testing or (iii) a self-sampling kit unsolicited (send-to-all) for HPV testing.Results Total participation was 4.8%, 17.0% and 27.7% among control, opt-in and send-to-all (P < 0.0001; participation difference (%) send-to-all vs. control: 22.9 (95%CI: 20.7, 25.2); opt-in vs. control: 12.3 (95%CI: 10.3, 14.2); send-to-all vs. opt-in: 10.7 (95% CI: 8.0, 13.3)). High-risk HPV was detected in 11.5% of self-samples and 9.2% of clinician-collected samples (P = 0.40). Most women (92.5%) who returned a positive self-sample attended the clinic for triage testing. Of the 933 women screened, 33 (3.5%) had CIN2 + (1.1%, 3.7%, 3.8% among control, opt-in, and send-to-all, respectively), and 11 (1.2%) had cervical cancer (0%, 1.2%, 1.3% among control, opt-in, send-to-all, respectively).Conclusion Opt-in and send-to-all self-sampling increased screening participation among long-term, higher-risk non-attenders.Clinical trial registration ClinicalTrials.gov NCT03873376.Subject terms: Preventive medicine, Population screening, Epidemiology  相似文献   
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