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31.
Yinon Y Kelly E Ryan G 《Best practice & research. Clinical obstetrics & gynaecology》2008,22(1):77-96
The clinical course of primary fetal hydrothorax is unpredictable. Whereas smaller unilateral effusions might remain stable or even regress, this is rarely the case with larger collections. Bilateral effusions, hydrops, preterm delivery and the lack of antenatal therapy are all associated with poor outcome. Once structural and chromosomal anomalies have been excluded, optimal management depends on gestational age, rate of progression, the development of hydrops and associated maternal symptoms. For very large effusions with mediastinal shift, hydrops and/or hydramnios, or when there is rapid enlargement of the effusion, fetal intervention is warranted. Survival can be maximized by pleuroamniotic shunting, which can reverse hydrops and hydramnios and prevent pulmonary hypoplasia. Pleuroamniotic shunting can also be used for the treatment of other large cystic lung lesions, such as a macrocystic congenital cystic adenomatoid malformation or bronchopulmonary sequestration, especially when associated with hydrops. 相似文献
32.
Victoria Hoyle Madison T. Flasco Jiyeong Choi Elizabeth J. Cieniewicz Heather McLane Keith Perry Gerald Dangl Maher Al Rwahnih Michelle Heck Greg Loeb Marc F. Fuchs 《Viruses》2022,14(6)
Grapevine red blotch disease emerged within the past decade, disrupting North American vine stock production and vineyard profitability. Our understanding of how grapevine red blotch virus (GRBV), the causal agent of the disease, interacts with its Vitis hosts and insect vector, Spissistilus festinus, is limited. Here, we studied the capabilities of S. festinus to transmit GRBV from and to free-living vines, identified as first-generation hybrids of V. californica and V. vinifera ‘Sauvignon blanc’ (Vcal hybrids), and to and from V. vinifera ‘Cabernet franc’ (Vvin Cf) vines. The transmission rate of GRBV was high from infected Vcal hybrid vines to healthy Vcal hybrid vines (77%, 10 of 13) and from infected Vvin Cf vines to healthy Vcal hybrid vines (100%, 3 of 3). In contrast, the transmission rate of GRBV was low from infected Vcal hybrid vines to healthy Vvin Cf vines (15%, 2 of 13), and from infected Vvin Cf vines to healthy Vvin Cf vines (19%, 5 of 27). No association was found between transmission rates and GRBV titer in donor vines used in transmission assays, but the virus titer was higher in the recipient leaves of Vcal hybrid vines compared with recipient leaves of Vvin Cf vines. The transmission of GRBV from infected Vcal hybrid vines was also determined to be trans-stadial. Altogether, our findings revealed that free-living vines can be a source for the GRBV inoculum that is transmissible by S. festinus to other free-living vines and a wine grape cultivar, illustrating the interconnected roles of the two virus hosts in riparian areas and commercial vineyards, respectively, for virus spread. These new insights into red blotch disease epidemiology will inform the implementation of disease management strategies. 相似文献
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ABSTRACT: For the first time since AIDS erupted as worldwide emergency, global leaders, the scientific community, activists and people living with HIV are venturing to speak about the end to the pandemic. Signs of hope abound: over 8 million people are receiving life-saving treatment, the number of new infections is on significant decline, the remarkable evidence of treatment's impact on preventing new infections and the aspiration of zero new HIV infections among children is firmly within grasp. This progress, won by countries with support from partners such as the US program PEPFAR, the Clinton Health Access Initiative and untold more, embodies global solidarity to bring about an AIDS-free generation. Shared responsibility and global solidarity represents a normative ideal to which both individual stakeholders and the global community must subscribe and embrace if our collective vision of an AIDS-free world is to be realised. The idea of shared responsibility and global solidarity needs to goes further than raising and investing resources and extend to the level of control countries take of their AIDS response. This editorial explores five areas that require specific attention. 相似文献
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Flaviana R. Fernandes Weverson A. Ferreira Mariana A. Campos Guilherme S. Ramos Kelly C. Kato Gregório G. Almeida José D. Corrêa Junior Maria N. Melo Cynthia Demicheli Frédéric Frézard 《Antimicrobial agents and chemotherapy》2013,57(9):4229-4236
The need for daily parenteral administration is an important limitation in the clinical use of pentavalent antimonial drugs against leishmaniasis. In this study, amphiphilic antimony(V) complexes were prepared from alkylmethylglucamides (L8 and L10, with carbon chain lengths of 8 and 10, respectively), and their potential for the oral treatment of visceral leishmaniasis (VL) was evaluated. Complexes of Sb and ligand at 1:3 (SbL8 and SbL10) were obtained from the reaction of antimony(V) with L8 and L10, as evidenced by elemental and electrospray ionization-tandem mass spectrometry (ESI-MS) analyses. Fluorescence probing of hydrophobic environment and negative-staining transmission electron microscopy showed that SbL8 forms kinetically stabilized nanoassemblies in water. Pharmacokinetic studies with mice in which the compound was administered by the oral route at 200 mg of Sb/kg of body weight indicated that the SbL8 complex promoted greater and more sustained Sb levels in serum and liver than the levels obtained for the conventional antimonial drug meglumine antimoniate (Glucantime [Glu]). The efficacy of SbL8 and SbL10 administered by the oral route was evaluated in BALB/c mice infected with Leishmania infantum after a daily dose of 200 mg of Sb/kg for 20 days. Both complexes promoted significant reduction in the liver and spleen parasite burdens in relation to those in the saline-treated control group. The extent of parasite suppression (>99.96%) was similar to that achieved after Glu given intraperitoneally at 80 mg of Sb/kg/day. As expected, there was no significant reduction in the parasitic load in the group treated orally with Glu at 200 mg of Sb/(kg day). In conclusion, amphiphilic antimony(V) complexes emerge as an innovative and promising strategy for the oral treatment of VL. 相似文献
37.
Abstract Twenty-five pediatric house officers were surveyed (14 M; 11 F) to assess their behavioral and psychophysiologic responses to patient death. Vignettes about the deaths of two pediatric patients were included as part of a self-administered questionnaire. The vignettes were followed by 14 behavioral and 20 psychophysiologic responses to the deaths depicted, and physicians were asked to indicate the expected occurrence of these reactions for themselves and for an ideal physician. Reported reactions were found to be similar to grief responses experienced with the death of a loved one. Significant differences were found between the responses of female and male house officers to patient death. Additionally, differences were found between the manner in which the physicians personally responded to a patient's death in comparison to the way they considered an ideal physician would respond. Practical suggestions are given, based on these data, for inclusion of information in death education courses for physicians. 相似文献
38.
39.
Human erythrocyte ghosts: exploring the origins of multiexponential water diffusion in a model biological tissue with magnetic resonance. 总被引:1,自引:0,他引:1
Peter E Thelwall Samuel C Grant Greg J Stanisz Stephen J Blackband 《Magnetic resonance in medicine》2002,48(4):649-657
A tissue model composed of erythrocyte ghosts was developed to study the effects of compartmentation on the MR signal acquired from biological tissues. This simple and flexible model offers control over the biophysical parameters that contribute to multicomponent signals arising from cellular systems. Cell density, size, intra- and extracellular composition, and membrane permeability can be independently altered. The effects of cell density and cell size on water diffusion properties were assessed. The data demonstrate non-monoexponential water diffusion in ghost cell suspensions of 17-67% cell density. Data were analysed with the widely employed two-compartment (biexponential) model, and with a two-compartment model that accounted for exchange between compartments. Water exchange between the intra- and extracellular compartments appeared to be significant over the range of diffusion times studied (7-35 ms). The biexponential fit to the ghost data appeared to be underparameterised as the ADCs and relative fractions of the fast and slow components were dependent on the experimental acquisition parameters, specifically the diffusion time. However, both analysis methods proved effective at tracking changes in the ghost model when it was perturbed. This was demonstrated with cell density variation, cell swelling and shrinkage experiments, and reduction of membrane water permeability using a water channel blocker (pCMBS). We anticipate that this model system could be used to investigate compartmental diffusion effects to simulate a range of pathologies, especially ischemic stroke. 相似文献
40.
Rezai AR Finelli D Nyenhuis JA Hrdlicka G Tkach J Sharan A Rugieri P Stypulkowski PH Shellock FG 《Journal of magnetic resonance imaging : JMRI》2002,15(3):241-250
PURPOSE: To assess magnetic resonance imaging (MRI)-related heating for a neurostimulation system (Activa Tremor Control System, Medtronic, Minneapolis, MN) used for chronic deep brain stimulation (DBS). MATERIALS AND METHODS: Different configurations were evaluated for bilateral neurostimulators (Soletra Model 7426), extensions, and leads to assess worst-case and clinically relevant positioning scenarios. In vitro testing was performed using a 1.5-T/64-MHz MR system and a gel-filled phantom designed to approximate the head and upper torso of a human subject. MRI was conducted using the transmit/receive body and transmit/receive head radio frequency (RF) coils. Various levels of RF energy were applied with the transmit/receive body (whole-body averaged specific absorption rate (SAR); range, 0.98-3.90 W/kg) and transmit/receive head (whole-body averaged SAR; range, 0.07-0.24 W/kg) coils. A fluoroptic thermometry system was used to record temperatures at multiple locations before (1 minute) and during (15 minutes) MRI. RESULTS: Using the body RF coil, the highest temperature changes ranged from 2.5 degrees-25.3 degrees C. Using the head RF coil, the highest temperature changes ranged from 2.3 degrees-7.1 degrees C.Thus, these findings indicated that substantial heating occurs under certain conditions, while others produce relatively minor, physiologically inconsequential temperature increases. CONCLUSION: The temperature increases were dependent on the type of RF coil, level of SAR used, and how the lead wires were positioned. Notably, the use of clinically relevant positioning techniques for the neurostimulation system and low SARs commonly used for imaging the brain generated little heating. Based on this information, MR safety guidelines are provided. These observations are restricted to the tested neurostimulation system. 相似文献