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991.
Susan J. Leach Richard A. Magill Joyce R. Maring 《Physiotherapy theory and practice》2017,33(1):72-81
A spinal cord injury (SCI) frequently results in impaired balance, endurance, and strength with subsequent limitations in functional mobility and community participation. The purpose of this case report was to implement a training program for an individual with a chronic incomplete SCI using a novel divided-attention stepping accuracy task (DASAT) to determine if improvements could be made in impairments, activities, and participation. The client was a 51-year-old male with a motor incomplete C4 SCI sustained 4 years prior. He presented with decreased quality of life (QOL) and functional independence, and deficits in balance, endurance, and strength consistent with central cord syndrome. The client completed the DASAT intervention 3 times per week for 6 weeks. Each session incorporated 96 multi-directional steps to randomly-assigned targets in response to 3-step verbal commands. QOL, measured using the SF-36, was generally enhanced but fluctuated. Community mobility progressed from close supervision to independence. Significant improvement was achieved in all balance scores: Berg Balance Scale by 9 points [Minimal Detectable Change (MDC) = 4.9 in elderly]; Functional Reach Test by 7.62 cm (MDC = 5.16 in C5/C6 SCI); and Timed Up-and-Go by 0.53 s (MDC not established). Endurance increased on the 6-Minute Walk Test, with the client achieving an additional 47 m (MDC = 45.8 m). Lower extremity isokinetic peak torque strength measures were mostly unchanged. Six minutes of DASAT training per session provided an efficient, low-cost intervention utilizing multiple trials of variable practice, and resulted in better performance in activities, balance, and endurance in this client. 相似文献
992.
993.
The direct infusion of macromolecules into defect sites generally does not impart adequate physiological responses. Without the protection of delivery systems, inductive molecules may likely redistribute away from their desired locale and are vulnerable to degradation. In order to achieve efficacy, large doses supplied at interval time periods are necessary, often at great expense and ensuing detrimental side effects. The selection of a delivery system plays an important role in the rate of re-growth and functionality of regenerating tissue: not only do the release kinetics of inductive molecules and their consequent bioactivities need to be considered, but also how the delivery system interacts and integrates with its surrounding host environment. In the current review, we describe the means of release of macromolecules from hydrogels, polymeric microspheres, and porous scaffolds along with the selection and utilization of bioactive delivery systems in a variety of tissue-engineering strategies. 相似文献
994.
Samantha Rowbotham Merryn McKinnon Joan Leach Rod Lamberts Penelope Hawe 《Critical public health》2019,29(1):118-128
Citizen science engages members of the public in research design, data collection, and analysis – in asking and answering questions about the world around them. The United States, European Union, and Australia have placed citizen science at the forefront of national science policy. Journals such as Science, Nature and Bioscience regularly feature projects conducted by citizens. Citizen science engages millions of people worldwide. However, to date, population health science has not relied heavily on citizen contributions. Although community-based participatory action research remains a strong foundational method to engage those affected by public health problems, there is additional potential to mainstream population health through wider, less intensive opportunities to be involved in our science. If we are to tackle the complex challenges that face population health then new avenues are needed to capture the energy and attention of citizens who may not feel affected by public health problems, i.e. to engage the ‘by-standers’ in population health science. Particular types of citizen science methods have the potential to do this. But simply increasing the breadth and volume of scientific evidence will not be enough. Complex, intractable, macro-level problems in population health require change in how our journals and funding bodies respond to data generated by the public. Of course, democratisation of science and the potential decentralisation of scientific authority will bring deep challenges. But potentially it brings a future where population health science is better known, understood and respected, with benefits for the types of public policies that derive from this science. 相似文献
995.
996.
SK&F 96067 [3-butyryl-4-(2-methylphenylamino)-8-methoxyquinoline] has been identified, from a novel class of 4-aminoquinolines, as a reversible inhibitor of the gastric (H+ + K+)-ATPase. This compound has been studied in gastric membrane vesicle preparations enriched in the (H+ + K+)-ATPase. At pH 7.0, SK&F 96067 inhibited K(+)-stimulated ATPase activity competitively with respect to the activating cation K+, with a Ki value of 0.39 +/- 0.05 microM. Under comparable conditions, SK&F 96067 was 32 times more potent as an inhibitor of the gastric (H+ + K+)-ATPase relative to the closely related (Na+ + K+)-ATPase. Studies in intact gastric vesicles showed that SK&F 96067 also inhibited hydrogen ion transport. Using the initial rate of acridine orange quenching as the index of acidification, an IC50 of 0.84 +/- 0.24 microM was observed. Steady state acidification, as measured by aminopyrine accumulation, was inhibited with greater potency (IC50 = 0.06 +/- 0.01 microM) consistent with the accumulation of this inhibitor into the intravesicular acidic space to a site of action on the inside (lumenal) face of the enzyme. Inhibition of ATPase activity in the presence of both SK&F 96067 and the K(+)-competitive (H+ + K+)-ATPase inhibitor, SCH 28080, indicated that their binding was mutually exclusive, consistent with SK&F 96067 acting at the same lumenal binding site as does SCH 28080. The steady-state inhibition kinetics of SK&F 96067 against K(+)-stimulated ATPase activity were followed as a function of pH. At pH 6.6 and 7.0 the inhibition was competitive with respect to the activating cation K+. At pH 7.5 and 8.1 a mixed pattern of inhibition was detected. Thus, at alkaline pH values, the binding of SK&F 96067 and K+ were no longer mutually exclusive. The potency of SK&F 96067 decreased as pH rose, consistent with the protonated form of the inhibitor being the preferred inhibitory species. A kinetic model is discussed, in which, at acidic pH, the protonated form of SK&F 96067 binds to the enzyme competitively with respect to K+, whereas, at alkaline pH, the neutral form of SK&F 96067 can bind simultaneously with K+. 相似文献
997.
L M Strawn R E Martell R U Simpson K L Leach R E Counsell 《Journal of medicinal chemistry》1989,32(3):643-648
Analogues of diacylglycerol containing a 3-(3-amino-2,4,6-triiodophenyl)-2-ethylpropanoyl or 3-(3-amino-2,4,6-triiodophenyl)propanoyl group in the 2-position (1a and 1b, respectively) were synthesized and shown to compete with [3H]phorbol dibutyrate [( 3H]PDBu) for binding in a crude rat brain preparation. Phorbol diesters have been shown to bind specifically to protein kinase C and the PDBu receptor has been copurified with protein kinase C activity. The four diastereomers of 1a (1c-f) were synthesized from chiral starting material and studied in the same assay. The affinities for the [3H]PDBu binding site of 1a, 1b, and two isomers of 1a with naturally occurring L configuration were comparable to that of 1-oleoyl-2-acetyl-rac-glycerol (OAG), but the D isomers of 1a were essentially inactive. The chirality of the side chain did not influence the binding affinity. Activation of protein kinase C by 1a, 1c, and 1e demonstrated the same stereochemical requirements, but none were as active as OAG. For the 1,3-isomers 2, 2a, and 2b, the competitive binding studies gave different results. The racemic mixture and the D isomer, 2b, were able to compete for binding, but the L isomer, 2a, did not compete. These studies demonstrate that diacylglycerol binding to and activation of protein kinase C is stereospecific for the glycerol backbone, but not the side chain. Furthermore, the D-1,3-isomer must exist in a conformation such that the acyl and hydroxyl oxygens assume a spatial relationship similar to that in the L-1,2-isomers. 相似文献
998.
Bacterially mediated N-nitrosation reactions and endogenous formation of N-nitroso compounds 总被引:1,自引:0,他引:1
S A Leach A R Cook B C Challis M J Hill M H Thompson 《IARC scientific publications》1987,(84):396-399
Results are presented demonstrating some factors that affect the kinetics of bacterially mediated N-nitrosation reactions. Two groups of bacteria, differing in their nitrate/nitrite metabolism, are contrasted. These findings are discussed in relation to a role for bacteria in endogenous N-nitrosation reactions. 相似文献
999.
S P Kelly N J MacDermott D C Saunders F N Leach 《The British journal of ophthalmology》1989,73(8):655-656
Tonic-clonic seizures followed intravenous fluorescein injection for fundus angiography in a 47-year-old male. Despite precautions this adverse reaction recurred on re-exposure to intravenous fluorescein. 相似文献
1000.
The rationale and clinical methods of percutaneous disc surgery have been modified during the past four years. Experience with a consecutive series of 48 patients suggests that the procedure now offers results comparable to open surgery and the advantages of reduced surgical trauma. 相似文献