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1.
In this issue of Immunity, Anderson et al. provide another clue to the riddle that is Aire--why do human beings and mice lacking Aire develop diffuse and pathogenic autoimmunity? They find that Aire influences central tolerance not only by promoting the expression of peripheral self-proteins in thymic medullary epithelial cells (MECs) but also by furnishing these cells with the apparatus for effective antigen presentation (). 相似文献
2.
Mallikarjuna Rao GN Hussain T Geetha Devi N Jain S Chandak GR Ananda Raj MP 《Indian journal of medical sciences》2003,57(1):1-6
66 unrelated patients from Southern India with Duchenne Muscular Dystrophy (DMD) were studied for intragenic deletion in 18 exons and Pm region of the DMD gene using multiplex PCR. Of these 41 (62.1%) showed intragenic deletions. 78% of the deletions were located at the distal hotspot region (44-55 exons) and 22% of the deletions were located at the proximal region (exon 2-19). Exon 50 is most frequently deleted. Deletions in isolated cases were significantly more compared to familial cases. The lower incidence reported from South India compared to North India, is suggestive of variations in the Southern and Northern population. 相似文献
3.
Few studies have examined the validity of metabolic equations for the prediction of energy cost (VO(2)) of arm ergometry in women. Therefore, the purpose of this study was (a) to compare directly measured and predicted VO(2) values using the American College of Sports Medicine (ACSM) equation and (b) to develop and validate a prediction equation for women. A sample of 60 female subjects with mean (+/-SD) age, weight and height 26.5 +/- 14.4 years, 61.5 +/- 7.6 kg, 163.3 +/- 6.0 cm, respectively, was randomly assigned to an equation group (N = 40) and a cross validation group (N = 20). All subjects performed an incremental arm ergometry test (10 W increases every 2 min), until termination criteria were met. Repeated measures ANOVA indicated significant differences between the measured VO(2) and ACSM predicted VO(2) during all the incremental test work rate. Multiple linear regression analysis was used to develop the following upper body exercise VO(2) prediction equation: VO(2)(ml . kg(-1) . min(-1) = 23.461 - (0.272 x Body Weight) + (0.403 x watts) [R(2) = 0.82, SEE = 2.79] Cross validation indicated lower variability using the current prediction equation. An additional independent sample of 13 subjects performed a 30-min steady-state test at 40% of their pre-determined maximal work rate. VO(2) measured during the 30 min steady-state test (was significantly different P < 0.05) from the ACSM prediction at all time intervals. There were no significant differences using the above equation following the 5 min time interval. Therefore, a new equation is proposed as a means of providing a gender-specific energy cost prediction equation. 相似文献
4.
Irina Maljkovic Berry Melanie C. Melendrez Simon Pollett Katherine Figueroa Darunee Buddhari Chonticha Klungthong Ananda Nisalak Michael Panciera Butsaya Thaisomboonsuk Tao Li Tyghe G. Vallard Louis Macareo In-Kyu Yoon Stephen J. Thomas Timothy Endy Richard G. Jarman 《Emerging infectious diseases》2021,27(6):1637
Dengue control approaches are best informed by granular spatial epidemiology of these viruses, yet reconstruction of inter- and intra-household transmissions is limited when analyzing case count, serologic, or genomic consensus sequence data. To determine viral spread on a finer spatial scale, we extended phylogenomic discrete trait analyses to reconstructions of house-to-house transmissions within a prospective cluster study in Kamphaeng Phet, Thailand. For additional resolution and transmission confirmation, we mapped dengue intra-host single nucleotide variants on the taxa of these time-scaled phylogenies. This approach confirmed 19 household transmissions and revealed that dengue disperses an average of 70 m per day between households in these communities. We describe an evolutionary biology framework for the resolution of dengue transmissions that cannot be differentiated based on epidemiologic and consensus genome data alone. This framework can be used as a public health tool to inform control approaches and enable precise tracing of dengue transmissions. 相似文献
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Nigussie Alebachew H. C. Ananda Murthy Bedassa Abdissa Taye B. Demissie Karel G. von Eschwege Ernst H. G. Langner Liza Coetsee-Hugo 《RSC advances》2022,12(46):29959
This study presents the simultaneous exfoliation and modification of heterostructured copper oxide incorporated sulfur doped graphitic carbon nitride (CuO@S-doped g-C3N4) nanocomposites (NCs) synthesized via chemical precipitation and pyrolysis techniques. The results revealed that the approach is feasible and highly efficient in producing 2-dimensional CuO@S-doped g-C3N4 NCs. The findings also showed a promising technique for enhancing the optical and electrical properties of bulk g-C3N4 by combining CuO nanoparticles (NPs) with S-doped g-C3N4. The crystallite and the average size of the NCs were validated using X-ray diffraction (XRD) studies. Incorporation of the cubical structured CuO on flower shaped S-doped-g-C3N4 was visualized and characterized through XRD, HR-SEM/EDS/SED, FT-IR, BET, UV-Vis/DRS, PL, XPS and impedance spectroscopy. The agglomerated NCs had various pore sizes, shapes and nanosized crystals, while being photo-active in the UV-vis range. The synergistic effect of CuO and S-doped g-C3N4 as co-modifiers greatly facilitates the electron transfer process between the electrolyte and the bare glassy carbon electrode. Specific surface areas of the NCs clearly revealed modification of bulk S-doped g-C3N4 when CuO NPs are incorporated with S-doped g-C3N4, providing a suitable environment for the binder-free decorated electrode with sensing behavior for hazardous pollutants. This was tested for the preparation of a 4-nitrophenol sensor.This study presents the simultaneous exfoliation and modification of heterostructured copper oxide incorporated sulfur doped graphitic carbon nitride (CuO@S-doped g-C3N4) nanocomposites synthesized via chemical precipitation and pyrolysis techniques. 相似文献
7.
Beatriz Togoro Ferreira da Silva Livia Tosi Trevelin Ananda Carolina Schroeter Amanda Endres Willers Paulo Francisco Cesar Adriana Bona Matos 《European journal of oral sciences》2021,129(1):e12754
This study investigated the effect of irradiation with an erbium‐doped yttrium aluminium garnet (Er:YAG) laser and coating with silica on the surface characteristics, bond strength, and flexural strength of dental zirconia. Three hundred and forty‐three standard zirconia specimens were created, and 49 were assigned to each of seven surface treatment groups: (i) no treatment; Er:YAG laser (80 mJ/2 Hz) with pulse widths of 50 μs (ii), 100 μs (iii), 300 μs (iv), or 600 μs (v); or tribochemical silica coating at the partially sintered stage (vi) or after sintering was complete (vii). All specimens were sintered after the surface treatments, except for the group in which specimens were sintered before treatment. The study outcomes were roughness, surface loss, microshear bond strength (μSBS), and biaxial flexural strength (BFS). Mean roughness and surface loss values were significantly higher in specimens from irradiated groups than in those from silica‐coated groups. Regarding μSBS, after aging, specimens from all experimental groups presented very low and similar μSBS values, irrespective of the surface treatment. Silica coating after sintering yielded the highest BFS (1149.5 ± 167.6 MPa), while coating partially sintered specimens with silica resulted a BFS (826.9 ± 60.9 MPa) similar to that of the untreated control group (794.9 ± 101.7 MPa). Laser treatments, irrespective of pulse width used, significantly decreased the BFS. In the group treated with laser at 300 μs pulse width, specimens exhibited the lowest BFS value (514.1 ± 71.5 MPa). Adhesion to zirconia was not stable after aging, regardless of the surface treatment implemented. 相似文献
8.
9.
Nina Vyas Kawa Manmi Qianxi Wang Ananda J. Jadhav Mostafa Barigou Rachel L. Sammons Sarah A. Kuehne A. Damien Walmsley 《Ultrasound in medicine & biology》2019,45(5):1044-1055
Bacterial biofilms are a cause of contamination in a wide range of medical and biological areas. Ultrasound is a mechanical energy that can remove these biofilms using cavitation and acoustic streaming, which generate shear forces to disrupt biofilm from a surface. The aim of this narrative review is to investigate the literature on the mechanical removal of biofilm using acoustic cavitation to identify the different operating parameters affecting its removal using this method. The properties of the liquid and the properties of the ultrasound have a large impact on the type of cavitation generated. These include gas content, temperature, surface tension, frequency of ultrasound and acoustic pressure. For many of these parameters, more research is required to understand their mechanisms in the area of ultrasonic biofilm removal, and further research will help to optimise this method for effective removal of biofilms from different surfaces. 相似文献
10.
Tumour necrosis factor alpha is an important mediator of portal and systemic haemodynamic derangements in alcoholic hepatitis 总被引:10,自引:0,他引:10 下载免费PDF全文
BACKGROUND: The role of proinflammatory cytokines in the pathogenesis of portal hypertension is unclear. AIMS AND METHODS: This study tests the hypothesis that tumour necrosis factor alpha (TNF-alpha) is an important mediator of the circulatory disturbances in alcoholic hepatitis (AH) and evaluates the acute and short term effect of a single infusion of the monoclonal chimeric anti-TNF-alpha antibody (Infliximab) on portal and systemic haemodynamics in 10 patients with severe biopsy proven AH. Cardiovascular haemodynamics, hepatic venous pressure gradient (HVPG), and hepatic and renal blood flow were measured before, 24 hours after Infliximab, and prior to hospital discharge. RESULTS: Serum bilirubin (p<0.05), C reactive protein (p<0.001), and white cell count (p<0.01) were reduced significantly, as were plasma levels of interleukin (IL)-6 and IL-8 after treatment. Of the 10 patients, nine were alive at 28 days. Mean HVPG decreased significantly at 24 hours (23.4 (2.8) to 14.3 (1.9) mm Hg; p<0.001) with a sustained reduction prior to discharge (12.8 (1.9) mm Hg; p<0.001). Mean arterial pressure and systemic vascular resistance increased significantly (p<0.001and p<0.01, respectively), mirrored by a reduction in cardiac index (5.9 (0.5) to 4.7 (0.5) l/min/m(2); p<0.05) prior to discharge. Hepatic and renal blood flow also increased significantly (506.2 (42.9) to 646.3 (49.2) ml/min (p=0.001) and 424.3 (65.12) to 506.3 (85.7) ml/min (p=0.001), respectively) prior to discharge. CONCLUSION: The results of this study illustrate that anti-TNF-alpha treatment in AH patients produces a highly significant, early, and sustained reduction in HVPG, possibly through a combination of a reduction in cardiac output and intrahepatic resistance. In addition, there was a reduction in hepatic inflammation and improved organ blood flow, suggesting an important role for TNF-alpha in mediating the circulatory disturbances in AH. 相似文献