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981.
Objective: The Brain Injury Cognitive Screen (BICS) was developed as an in-service cognitive assessment battery for acquired brain injury patients entering community rehabilitation. The BICS focuses on domains that are particularly compromised following TBI, and provides a broader and more detailed assessment of executive function, attention and information processing than comparable screening assessments. The BICS also includes brief assessments of perception, naming, and construction, which were predicted to be more sensitive to impairments following non-traumatic brain injury. The studies reported here examine preliminary evidence for its validity in post-acute rehabilitation. Method: In Study 1, TBI patients completed the BICS and were compared with matched controls. Patients with focal lesions and matched controls were compared in Study 2. Study 3 examined demographic effects in a sample of normative data. Results: TBI and focal lesion patients obtained significantly lower composite memory, executive function and attention and information processing BICS scores than healthy controls. Injury severity effects were also obtained. Logistic regression analyses indicated that each group of BICS memory, executive function and attention measures reliably differentiated TBI and focal lesion participants from controls. Design Recall, Prospective Memory, Verbal Fluency, and Visual Search test scores showed significant independent regression effects. Other subtest measures showed evidence of sensitivity to brain injury. Conclusions: The study provides preliminary evidence of the BICS’ sensitivity to cognitive impairment caused by acquired brain injury, and its potential clinical utility as a cognitive screen. Further validation based on a revised version of the BICS and more normative data are required.  相似文献   
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984.
Recent neuroanatomical and functional neuroimaging studies indicate that the anterior part of the hippocampus, rather than the whole structure, may be specifically involved in episodic memory. In the present work, we examined whether anterior structural measurements are superior to other regional or global measurements in mapping functionally relevant degenerative alterations of the hippocampus in Alzheimer's disease (AD).Twenty patients with early AD (MMSE 25.7 ± 1.7) and 18 healthy controls were studied using magnetic resonance and diffusion-tensor imaging. Using a regions-of-interest analysis, we obtained volumetric and diffusivity measures of the hippocampal head and body-tail-section as well as of the whole hippocampus. Detailed cognitive evaluation was based on the CERAD battery.All volumetric measures as well as diffusivity of the hippocampus head were significantly (p < 0.01) altered in patients as compared to controls. In patients, increased left head diffusivity significantly (p < 0.01) correlated with performance on free delayed verbal recall test (DVR) (r = −0.74, p = 0.0002) and with the CERAD global score. Reduced volume of the left body-tail was also associated with performance on DVR (r = 0.62, p = 0.004). Stepwise regression analyses revealed that increased left head diffusivity was the only predictor for performance on DVR (R2 = 52%, p < 0.0005).These findings suggest that anterior hippocampus diffusivity is more closely related to verbal episodic memory impairment than other regional or global structural measures. Our data support the hypothesis of functional differentiation in general and the specific role of the anterior hippocampus in episodic memory in particular. Diffusivity measurements might be highly sensitive to functionally relevant degenerative alterations of the hippocampus.  相似文献   
985.
Vocabulary acquisition represents a major challenge in foreign language learning. Research has demonstrated that gestures accompanying speech have an impact on memory for verbal information in the speakers' mother tongue and, as recently shown, also in foreign language learning. However, the neural basis of this effect remains unclear. In a within‐subjects design, we compared learning of novel words coupled with iconic and meaningless gestures. Iconic gestures helped learners to significantly better retain the verbal material over time. After the training, participants' brain activity was registered by means of fMRI while performing a word recognition task. Brain activations to words learned with iconic and with meaningless gestures were contrasted. We found activity in the premotor cortices for words encoded with iconic gestures. In contrast, words encoded with meaningless gestures elicited a network associated with cognitive control. These findings suggest that memory performance for newly learned words is not driven by the motor component as such, but by the motor image that matches an underlying representation of the word's semantics. Hum Brain Mapp, 2011. © 2010 Wiley‐Liss, Inc.  相似文献   
986.
Our objective was to identify the physiological measures that are sensitive to assessing cognitive workload across the spectrum of cognitive impairments. Three database searches were conducted: PubMed, PsychINFO, and Web of Science. Studies from the last decade that used physiological measures of cognitive workload in older adults (mean age >65 years-old) were reviewed. The cognitive workload of healthy older individuals was compared with the cognitive workload of younger adults, patients with mild cognitive impairment (MCI), and patients with Alzheimer’s diseases (AD). The most common measures of cognitive workload included: electroencephalography, magnetoencephalography, functional magnetic resonance imaging, pupillometry, and heart rate variability. These physiological measures consistently showed greater cognitive workload in healthy older adults compared to younger adults when performing the same task. The same was observed in patients with MCI compared to healthy older adults. Behavioral performance declined when the available cognitive resources became insufficient to cope with the cognitive demands of a task, such as in AD. These findings may have implications for clinical practice and future cognitive interventions.  相似文献   
987.
988.
黎永明  邓奋奎 《中国医药》2012,7(7):881-882
目的 研究80岁以上高龄患者髋关节置换术后认知功能的情况并分析发生认知功能障碍(POCD)的原因、危险因素和防治措施.方法 根据Rasmussen等推荐的诊断标准,结合简易智能量表(MMSE)对118例80岁以上髋关节置换术后患者进行评定.对诊断为POCD的患者,经治疗症状缓解后,再次行MMSE评分.结果 本组118例高龄患者中有8例发生POCD,发生率为6.8%.经对症处理和心理治疗后,8例均恢复正常.结论 80岁以上高龄患者行髋关节置换术存在POCD的诸多易发因索.麻醉医师应严格控制围术期各种高危因素,最大限度的减少麻醉手术引起的创伤和应激,从而有效预防POCD的发生.  相似文献   
989.
Abstract

1.?Folate, an essential micronutrient, is a critical cofactor in one-carbon metabolism. Mammals cannot synthesize folate and depend on supplementation to maintain normal levels. Low folate status may be caused by low dietary intake, poor absorption of ingested folate and alteration of folate metabolism due to genetic defects or drug interactions.

2.?Folate deficiency has been linked with an increased risk of neural tube defects, cardiovascular disease, cancer and cognitive dysfunction. Most countries have established recommended intakes of folate through folic acid supplements or fortified foods. External supplementation of folate may occur as folic acid, folinic acid or 5-methyltetrahydrofolate (5-MTHF).

3.?Naturally occurring 5-MTHF has important advantages over synthetic folic acid – it is well absorbed even when gastrointestinal pH is altered and its bioavailability is not affected by metabolic defects. Using 5-MTHF instead of folic acid reduces the potential for masking haematological symptoms of vitamin B12 deficiency, reduces interactions with drugs that inhibit dihydrofolate reductase and overcomes metabolic defects caused by methylenetetrahydrofolate reductase polymorphism. Use of 5-MTHF also prevents the potential negative effects of unconverted folic acid in the peripheral circulation.

4.?We review the evidence for the use of 5-MTHF in preventing folate deficiency.  相似文献   
990.
Cognitive reappraisal and expressive suppression, two major emotion regulation strategies, are differentially related to emotional well-being. The aim of this study was to test the association of individual differences in these two emotion regulation strategies with gray matter volume of brain regions that have been shown to be involved in the regulation of emotions. Based on high-resolution magnetic resonance images of 96 young adults voxel-based morphometry was used to analyze the gray matter volumes of the a priori regions of interest, including amygdala, insula, dorsal anterior cingulate and paracingulate cortex, medial and lateral prefrontal cortex (PFC) and their association with cognitive reappraisal and expressive suppression usage as well as neuroticism. A positive association of cognitive reappraisal with right and tendentially left amygdala volume and of neuroticism with left amygdala volume (marginally significant) was found. Expressive suppression was related to dorsal anterior cingulate/paracingulate cortex and medial PFC gray matter volume. The results of this study emphasize the important role of the amygdala in individual differences in cognitive reappraisal usage as well as neuroticism. Additionally, the association of expressive suppression usage with larger volumes of the medial PFC and dorsal anterior/paracingulate cortex underpins the role of these regions in regulating emotion-expressive behavior.  相似文献   
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