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991.

Purpose of review

Throwing places high demands on the human body, and specific characteristics are developed over time unique to these athletes. When returning to throw after injury, it is important to follow a criterion-based progression that allows the body to be prepared appropriately for the stresses that throwing will require. There is currently a void in the literature for criteria-based progression that helps these athletes return to the highest level of play.

Recent findings

As injury rates continue to rise in baseball, there is increased evidence showing contributions of the core and lower extremity to the baseball pitch. There is also additional data showing pitcher specific characteristics such as range of motion and scapular position in this unique population. The rehab professional should take into account every phase of the pitch starting from balance through ball release when designing a comprehensive return-to-throwing program.

Summary

Returning an athlete back to a throwing sport can be an overwhelming task. The rehabilitation specialist must have a sound understanding of the throwing motion as well as any biomechanical implications on the body, contributions throughout the kinetic chain, range of motion, and strength characteristics specific to the thrower as well as proper tissue loading principles. It is important that these athletes are not progressed too quickly through their programs and that a criteria-based progression is followed. They should have normalized range of motion, strength, and scapular mechanics, followed by a sound plyometric progression. Once this is achieved, they are advanced to an interval throwing program with increasing distance, effort, and volume which should be tracked for workload, making sure they do not throw more than their body is prepared for.
  相似文献   
992.

Purpose of Review

The purpose of this review is to highlight recent hardware and software advances in coronary computed tomography angiography (CTA) that make it a potentially viable alternative to invasive coronary angiography for surveillance of cardiac allograft vasculopathy (CAV) in heart transplant recipients.

Recent Findings

Dual-source CT, multisegment reconstruction, and intracycle motion correction algorithms are all technologies applied during or after image acquisition that can improve image quality and diagnostic accuracy in patients with elevated heart rates, such as heart transplant recipients. CT fractional flow reserve may also add value in this clinical scenario.

Summary

Coronary CTA now has equivalent diagnostic accuracy, offers more nuanced anatomic information, is inherently safer, and could be less costly than invasive coronary angiography. For these reasons, coronary CTA may now be a viable alternative to ICA for CAV surveillance in heart transplant recipients.
  相似文献   
993.
994.

Purpose of Review

The purpose of this review is to summarize the new guidelines from the American Society of Echocardiography (ASE) and the European Association of Cardiovascular Imaging (EACVI) for the diagnosis and grading of diastolic dysfunction (DD), with commentary on the rationale behind the use of the recommended individual parameters.

Recent Findings

Previous guidelines for assessment of diastolic function have been criticized for being too complex with modest diagnostic performance and inter-observer variability.

Summary

The new ASE/EACVI diastology guidelines aim to simplify the diagnosis and gradation of DD by using a limited set of echocardiographic variables. The robustness of these recommendations has been subsequently validated in several trials. Understanding the physiological principles that govern changes in echocardiographic parameters during normal and abnormal diastolic function is critical for the appropriate application of these recommendations.
  相似文献   
995.
This study examined the effects of two types of physical activities on stereotypic behaviors (SBs) and task engagement of young children with autism spectrum disorder. Locomotor activities and object manipulation activities were applied to three preschoolers with autism spectrum disorder. A multi-element design with a three-component test sequence (Morrison et al. Journal of Applied Behavior Analysis, 44, 523–541, 2011) was used to identify changes in SBs and task engagement in the following three consecutive 5-min phases: pre-physical activity (pre-PA), physical activity (PA), and post-physical activity (post-PA). For the locomotor activity condition, all participants engaged in less SBs in post-PA compared to pre-PA, while increased SBs were observed in post-PA compared to pre-PA for the object manipulation activity condition. Positive effects of locomotor activities on task engagement were found, but the effects were clear to only one of the three participants.  相似文献   
996.
This study examined the feasibility and preliminary outcomes of a comprehensive summer psychosocial treatment (summerMAXyc) for high-functioning young children, ages 4–6 years, with ASD (HFASD). The 5-week treatment, conducted 5 days per week, 6 h per day, included skills instruction and therapeutic activities targeting social/social-communication skills, facial-emotion recognition, and interest expansion. A behavioral system was implemented to increase skills acquisition and maintenance and reduce ASD symptoms and problem behaviors. Feasibility was supported in high levels of treatment fidelity and child, parent, and staff clinician satisfaction. Significant post-treatment improvements were found for 9 of 10 outcome measures including parent and staff clinician ratings of targeted social/social-communication skills, ASD symptoms, and broader adaptive social and communication skills, and staff clinician ratings of daily living skills. Results suggested that summerMAXyc was feasible and may yield positive outcomes for 4–6 year olds with HFASD.  相似文献   
997.
This paper reports a systematic review of prompt-fading research, with a focus on experiments comparing two or more prompt-fading procedures. Forty-five articles with 46 experiments met the operationally-defined inclusion criteria. For the selected articles, data on several variables were extracted and analyzed. Research demonstrated that all prompt-fading procedures were generally effective in promoting acquisition of behavior. Stimulus prompting was more effective and efficient when compared to response-prompting procedures. Comparisons of response-prompting procedures yielded variable efficiency results. These outcomes are discussed in terms of the behavioral principles that facilitate transfer of stimulus control from the prompt to the discriminative stimulus, such as blocking and overshadowing. Basic investigations of the role of these behavioral principles might help develop prompt-fading procedures that are consistently effective across participants. Implications for research include suggestions for the development of individualized assessments of stimulus control, similar to the functional analysis methodology.  相似文献   
998.
This study explores how self-determination relates to integration among deaf or hard of hearing (DHH) and hearing university students in mainland China. The American Institutes for Research (AIR) Self-Determination Scale and the Institutional Integration Scale were administered to 300 DHH students and 250 hearing students. Results showed that those with higher levels of self-determination tended to be more integrated, while those with lower levels scored lower on the Institutional Integration Scale. The limitations, contributions, and implications of the present research are discussed.  相似文献   
999.

Background

Heart failure (HF) is characterized by altered myocardial substrate metabolism which can lead to myocardial triglyceride accumulation (steatosis) and lipotoxicity. However its role in mild HF with preserved ejection fraction (HFpEF) is uncertain. We measured myocardial triglyceride content (MTG) in HFpEF and assessed its relationships with diastolic function and exercise capacity.

Methods

Twenty seven HFpEF (clinical features of HF, left ventricular EF >50%, evidence of mild diastolic dysfunction and evidence of exercise limitation as assessed by cardiopulmonary exercise test) and 14 controls underwent 1H-cardiovascular magnetic resonance spectroscopy (1H-CMRS) to measure MTG (lipid/water, %), 31P-CMRS to measure myocardial energetics (phosphocreatine-to-adenosine triphosphate - PCr/ATP) and feature-tracking cardiovascular magnetic resonance (CMR) imaging for diastolic strain rate.

Results

When compared to controls, HFpEF had 2.3 fold higher in MTG (1.45?±?0.25% vs. 0.64?±?0.16%, p?=?0.009) and reduced PCr/ATP (1.60?±?0.09 vs. 2.00?±?0.10, p?=?0.005). HFpEF had significantly reduced diastolic strain rate and maximal oxygen consumption (VO2 max), which both correlated significantly with elevated MTG and reduced PCr/ATP. On multivariate analyses, MTG was independently associated with diastolic strain rate while diastolic strain rate was independently associated with VO2 max.

Conclusions

Myocardial steatosis is pronounced in mild HFpEF, and is independently associated with impaired diastolic strain rate which is itself related to exercise capacity. Steatosis may adversely affect exercise capacity by indirect effect occurring via impairment in diastolic function. As such, myocardial triglyceride may become a potential therapeutic target to treat the increasing number of patients with HFpEF.
  相似文献   
1000.

Background

Although the mechanism of chronic migraine (CM) is unclear, it might be related to central sensitization and neuronal persistent hyperexcitability. The tyrosine phosphorylation of NR2B (NR2B-pTyr) reportedly contributes to the development of central sensitization and persistent pain in the spinal cord. Central sensitization is thought to be associated with an increase in synaptic efficiency, but the mechanism through which NR2B-pTyr regulates synaptic participation in CM-related central sensitization is unknown. In this study, we aim to investigate the role of NR2B-pTyr in regulating synaptic plasticity in CM-related central sensitization.

Methods

Male Sprague-Dawley rats were subjected to seven inflammatory soup (IS) injections to model recurrent trigeminovascular or dural nociceptor activation, which is assumed to occur in patients with CM. We used the von Frey test to detect changes in mechanical withdrawal thresholds, and western blotting and immunofluorescence staining assays were performed to detect the expression of NR2B-pTyr in the trigeminal nucleus caudalis (TNC). NR2B-pTyr was blocked with the Src family kinase inhibitor 4-amino-5-(4-chlorophenyl)-7-(t-butyl)-pyrazolo [3,4-d] pyrimidine (PP2) and the protein tyrosine kinase inhibitor genistein to detected the changes in calcitonin gene-related peptide (CGRP), substance P (SP), and the synaptic proteins postsynaptic density 95 (PSD95), synaptophysin (Syp), synaptotagmin1 (Syt-1). The synaptic ultrastructures were observed by transmission electron microscopy (TEM), and the dendritic architecture of TNC neurons was observed by Golgi-Cox staining.

Results

Statistical analyses revealed that repeated infusions of IS induced mechanical allodynia and significantly increased the expression of NR2B Tyr-1472 phosphorylation (pNR2B-Y1472) and NR2B Tyr-1252 phosphorylation (pNR2B-Y1252) in the TNC. Furthermore, the inhibition of NR2B-pTyr by PP2 and genistein relieved allodynia and reduced the expression of CGRP, SP, PSD95, Syp and Syt-1 and synaptic transmission.

Conclusions

These data indicate that NR2B-pTyr might regulate synaptic plasticity in central sensitization in a CM rat model. The inhibition of NR2B tyrosine phosphorylation has a protective effect on threshold dysfunction and migraine attacks through the regulation of synaptic plasticity in central sensitization.
  相似文献   
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