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Corrosion is frequently viewed as a catastrophic and unavoidable disaster in marine applications. Every year, a huge cost is incurred on the maintenance and repair of corrosion-affected equipment and machinery. In the marine environment, as-cast nickel–aluminium bronze (NAB) is susceptible to selective phase corrosion. To solve this problem, chromium-reinforced nickel–aluminium bronze was fabricated using the friction stir process (FSP) with improved microstructures and surface properties. A slurry erosion–corrosion test on as-cast and FSPed composites demonstrated that the developed surfaced composite has lower erosion and corrosion rates than the as-cast NAB alloy. The erosion–corrosion rate increased with a decrease in the impact angle from 90° to 30° for both as-cast NAB and prepared composites, exhibiting a shear mode of erosion. The specimens at impact angle 30° experienced more pitting action and higher mass loss compared with those at impact angle 90°. Due to increases in the mechanical properties, the FS-processed composite showed higher erosion resistance than the as-cast NAB alloy. Furthermore, corrosion behaviour was also studied via the static immersion corrosion test and electrochemical measurements under 3.5 wt.% NaCl solution. In a static immersion corrosion test, the FSPed composite outperformed the as-cast NAB composite by a wide margin. The FSPed composite also demonstrated a reduced electrochemical corrosion rate, as revealed by the polarization curve and electrochemical impedance spectroscopic (EIS) data. This reduced rate is attributed to the formation of a Cr oxide film over its surface in the corrosive environment. 相似文献
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S K Dutta 《Journal of the American College of Nutrition》2013,32(6):544-545
The media is the most popular vehicle through which consumers receive nutrition information, and is powerful in influencing food selection and health behaviors. Unfortunately, media messages surrounding nutrition are often inconsistent, confusing, and do not enable the public to make positive changes in health behaviors. The process to improve this scenario begins with communication between scientists and journalists. Scientists can take several steps to insure the results of their research are reported to the public accurately and, thereby, contribute to the achievement of the nation's public health goals. 相似文献
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Anindita Dutta Sanghita Roychoudhury Saswati Chowdhury Manas Ranjan Ray 《International journal of hygiene and environmental health》2013,216(3):301-308
To perform sputum analysis for verification of pulmonary changes in premenopausal rural Indian women chronically exposed to biomass smoke during cooking.Three consecutive morning sputum samples were collected from 196 women (median age 34 years) cooking with biomass and 149 age-matched control women cooking with cleaner fuel liquefied petroleum gas. Smears made on slides were stained with Papanicolaou and Perl's Prussian blue. Airway oxidative stress was estimated as reactive oxygen species (ROS) generation (by flow cytometry) and superoxide dismutase (SOD) level (by spectrophotometry) in sputum cells. Airway inflammation was measured as sputum levels of interleukin (IL)-6, -8 and tumor necrosis factor- alpha (TNF-α). Particulate matter of diameter less than 10 (PM10) was measured using laser photometer while benzene exposure was monitored by measuring trans, trans-muconic acid (t,t-MA) in urine by HPLC-UV. Compared with control, sputum of biomass users contained more neutrophils, lymphocytes, eosinophils, alveolar macrophages, and showed presence of ciliocytophthoria, Charcot-Leyden crystals, Curschmann's spiral. ROS generation was increased by 2-fold while SOD was depleted by 31% in biomass users. They also had higher sputum levels of IL-6, -8 and TNF-α. Levels of PM10 and t,t-MA were 2.9- and 5.8-times higher in biomass-using women. PM10 and t,t-MA levels were positively associated with cellular changes in the sputum, markers of airway inflammation, and oxidative stress. Cooking with biomass alters sputum cytology, and increases airway inflammation and oxidative stress that might result in further amplification of the tissue damaging cascade in women chronically exposed to biomass smoke. 相似文献
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Dutta S Crumley AB Fullarton GM Horgan PG McMillan DC 《World journal of surgery》2011,35(8):1861-1866
Background
Evidence is increasing that elevated systemic inflammation is associated with poor survival in patients with oesophageal carcinoma. However, it is not yet established if any specific component of systemic inflammatory response is a better predictor of cancer survival. The aim of the present study was to compare the predictive value of selected markers of systemic inflammation in patients who undergo surgical resection of oesophageal cancer.Methods
One hundred twelve patients who underwent potentially curative resection for oesophageal carcinoma, including type I and type II tumours of the gastro-oesophageal junction (Siewert and Stein in Dis Esophagus 9:173?C182, 1996), between 1996 and 2008 were included in the study. Patients had laboratory measurement of white cells, neutrophils, lymphocytes, platelet counts, albumin, and C-reactive protein. Glasgow Prognostic Score (mGPS), neutrophil lymphocyte ratio (NLR), platelet lymphocyte ratio (PLR), and metastatic lymph node ratio (LNR) were calculated.Results
On multivariate analysis, only the LNR (HR 2.87, 95% CI 1.99-4.15, p?0.001) and the mGPS (HR 4.31, 95% CI 2.20-8.45, p?0.001) were independently associated with cancer-specific survival in oesophageal cancer. An elevated mGPS was associated with high white cell count (p?0.05) and poorer survival (p?=?0.001).Conclusion
The present study indicates that the mGPS, an acute-phase protein-based prognostic score, better predicts cancer survival compared with the cellular components of systemic inflammation in patients with oesophageal carcinoma. 相似文献28.
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Background
Medical intelligence of disease vectors deals with understanding vector distribution and control.Methods
An entomological baseline survey using standard vector sampling techniques was done as a pilot study to map the vectors of defence importance in two cantonments of Pune with a view to establish a vector databank and impart training to armed forces personnel in vector surveillance.Result
The project trained 142 armed forces personnel in surveillance techniques in three years. Seventeen species of mosquitoes comprising of eight vector species were collected. Three other vectors viz. Rhipicephalus sanguineus, Xenopsylla cheopis and Leptotrombidium deliense are reported.Conclusion
The study emphasizes the need for vector mapping /surveillance in each area for preventing morbidity and mortality amongst troops. It also focuses on indigenous fabrication of vector sampling tools and training of personnel for capacity building which in turn will enable such surveys to be undertaken in other units and deployment areas.Key Words: Leptotrombidium, Mosquitoes, Rhipicephalus, Surveillance, Xenopsylla 相似文献30.