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31.
Summary The aim of the present study was to investigate the discriminative power of a series of variables (including determination of depressive symptomatology by means of a visual analogue scale, determination of personality traits by means of the Karolinska Scales of Personality, determination of monoamine metabolites in CSF, platelet MAO activities, serum cortisol before and after dexamethasone suppression and urinary melatonin) in differentiating (a) chronic pain patients from healthy subjects, and (b) patients with idiopathic pain syndromes from patients with neurogenic pain syndromes. Separately each of the measures gave a significant but often low contribution to the discrimination, while a combination of several measures gave a complete discrimination both between healthy subjects and patients with chronic pain syndromes and between patients with idiopathic and neurogenic pain syndromes, respectively.Supported in part by grants from the Swedish Medical Research Council (grants no. 3371, 4145 and 5740) and by a grant from Stiftelsen Söderström-Königska Sjukhemmet  相似文献   
32.
A model is described for obtaining long-term and stable discriminative conditioning-related slow-potential and single-unit responses from the frontal cortex of urethane-anesthetized rats. Responses were recorded and analyzed to reinforced (rewarding medial forebrain bundle stimulation) and non-reinforced tone cues. In the present study, cortical event-related slow potentials provided an adequate index of the level of discriminative conditioning. Single-unit response patterns are described for 57 neurons which demonstrated a discriminative response to either the reinforced or non-reinforced tone cue.  相似文献   
33.
An antibody against the calcium binding protein parvalbumin selectively labels a set of neurons in the cerebral cortex of lizards. Golgi-like immunostained bipolar, multipolar and pyramid-like neurons appear mainly located in the inner plexiform layers. Parvalbumin-immunoreactive (PARV-IR) puncta are concentrated in the cell layer of the dorsal and dorsomedial cortices showing a basket-like distribution. The morphology and distribution of PARV-IR neurons and puncta overlap GABA-immunostaining in the cerebral cortex of lizards. Thus, it is likely that PARV-IR neurons are a subset of the cortical GABAergic neurons of lizards.  相似文献   
34.
目的利用血氧水平依赖性功能性磁共振成像(BOLD-fMR I)技术,探索人类近视性屈光参差是否对大脑皮层功能和结构造成影响。方法采用无磁MR I专用眼镜纠正屈光不正,以1.5T磁共振成像系统采集8例近视性屈光参差者枕叶视皮层兴趣区BOLD-fMR I数据,比较双眼皮层激活部位及范围的不同,及视力较差眼屈光纠正前后皮层激活情况的变化,分析其改变特点及机制。结果矫正屈光基础上,近视性屈光参差者双眼激活范围没有明显差异(P>0.05);视力较差眼屈光矫正前后皮层激活范围有明显差异(P<0.05)。结论人类近视性屈光参差可能没有发生明显的皮层功能损害及优势眼的转移;配镜可明显提高视力较差眼的皮层激活,应尽早配镜或手术矫正。  相似文献   
35.
BACKGROUND: Facial emotions are central to human interaction. Identifying pathophysiology in affect processing circuitry that supports the ability to assess facial emotions might facilitate understanding of affect regulation in pediatric bipolar disorder. METHODS: Ten euthymic, unmedicated pediatric bipolar patients and 10 healthy control subjects matched for age, gender, race, socioeconomic status, and IQ were scanned with functional magnetic resonance imaging. Angry, happy, and neutral faces were presented in 30-sec blocks, with a 20-sec rest period between blocks. Subjects were asked to press a button when each face appeared, to ensure that attention was maintained on-task. RESULTS: In bipolar patients, in response to both angry and happy faces relative to neutral faces, we observed reduced activation of right rostral ventrolateral prefrontal cortex together with increased activity in right pregenual anterior cingulate, amygdala, and paralimbic cortex. Bipolar patients also showed reduced activation of visual areas in occipital cortex together with greater activation in higher-order visual perceptual areas, including superior temporal sulcus and fusiform gyrus with angry faces and posterior parietal cortex with happy faces. CONCLUSIONS: Findings document a disturbance in affective neurocircuitry in pediatric bipolar disorder. Reduced activation in ventrolateral prefrontal cortex might reflect diminished top-down control that leads to the observed exaggerated activation in amygdala and paralimbic areas. Changes in occipital areas might represent an effort to gate sensory input when affective responses to the faces could not be successfully modulated. Disturbances in affect processing circuitry could contribute to emotional dysregulation and social cognitive difficulties in bipolar youth.  相似文献   
36.
BACKGROUND: Functional neuroimaging studies have detected abnormal limbic and paralimbic activation to emotional probes in posttraumatic stress disorder (PTSD), but few studies have examined neurochemical mechanisms that underlie functional alterations in regional cerebral blood flow. The mu-opioid neurotransmitter system, implicated in responses to stress and suppression of pain, is distributed in and is thought to regulate the function of brain regions that are implicated in affective processing. METHODS: Here we examined the micro-opioid system with positron emission tomography and the micro-opioid receptor-selective radiotracer [11C] carfentanil in 16 male patients with PTSD and two non-PTSD male control groups, with (n = 14) and without combat exposure (n = 15). Differences in micro-opioid receptor binding potential (BP2) were detected within discrete limbic and paralimbic regions. RESULTS: Relative to healthy controls, both trauma-exposed groups had lower micro-opioid receptor BP2 in extended amygdala, nucleus accumbens, and dorsal frontal and insular cortex but had higher BP2 in the orbitofrontal cortex. PTSD patients exhibited reduced BP2 in anterior cingulate cortex compared with both control groups. Micro-opioid receptor BP2 in combat-exposed subjects without PTSD was lower in the amygdala but higher in the orbitofrontal cortex compared with both PTSD patients and healthy controls. CONCLUSIONS: These findings differentiate the general response of the micro-opioid system to trauma from more specific changes associated with PTSD.  相似文献   
37.
BACKGROUND: Perfusion functional magnetic resonance imaging (fMRI) was used to investigate the effect of genetic variation of the human serotonin transporter (5-HTT) gene (5-HTTLPR, SLC6A4) on resting brain function of healthy individuals. METHODS: Twenty-six healthy subjects, half homozygous for the 5-HTTLPR short allele (s/s group) and half homozygous for the long allele (l/l group), underwent perfusion functional and structural magnetic resonance imaging during a resting state. The two genotype groups had no psychiatric illness and were similar in age, gender, and personality scores. RESULTS: Compared with the l/l group, the s/s group showed significantly increased resting cerebral blood flow (CBF) in the amygdala and decreased CBF in the ventromedial prefrontal cortex. The effect of functional modulation in these regions by 5-HTTLPR genotype cannot be accounted for by variations in brain anatomy, personality, or self-reported mood. CONCLUSIONS: The 5-HTTLPR genotype alters resting brain function in emotion-related regions in healthy individuals, including the amygdala and ventromedial prefrontal cortex. Such alterations suggest a broad role of the 5-HTT gene in brain function that may be associated with the genetic susceptibility for mood disorders such as depression.  相似文献   
38.
The present study investigated relationships between global QOL perceptions and well-being dimensions. Especially our goal was to evaluate the impact of generally recognised four broad dimensions of QOL (physical, functional, social and emotional well-being) on global QOL perceptions, additionally person's satisfaction with life achievements and economical situation were measured as well as social demographic variables. The subjects were a representative sample of Finns (n = 4613, from 25 to 65 years) of the FINRISK-97 study. Correlation coefficients and models of hierarchical regression indicated that physical, functional and social well-being as well as sociodemographic factors and satisfaction with life achievements are important factors of global QOL perceptions both among males and females. However percentages of variances explained with these measures were only moderately high, ranging from 1 to 10%. After measures of emotional well-being were entered into the models of hierarchical analyses of regression, variances explained grew dramatically over 20%. The results of the study indicated that global QOL judgements are likely to be based on current emotional state.  相似文献   
39.
Understanding the mechanisms of food intake and obesity   总被引:2,自引:1,他引:1  
  相似文献   
40.
Flavocoxid (Limbrel), a proprietary mixture of flavonoid molecules (baicalin and catechin), was tested against a traditional nonsteroidal anti-inflammatory drug, naproxen, for the management of the signs and symptoms of moderate osteoarthritis (OA) in humans. Discomfort and global disease activity were used as the primary end points, and safety assessments were also taken for both treatments as a secondary endpoint. In this double-blind study, 103 subjects were randomly assigned to receive either flavocoxid [500 mg twice daily (BID)] or naproxen (500 mg BID) in a 1-month onset of action trial. Outcome measures included the short Western Ontario and McMaster University Osteoarthritis Index, subject Visual Analogue Scale for discomfort and global response, and investigator Visual Analogue Scale for global response and fecal occult blood. Both flavocoxid and naproxen showed significant reduction in the signs and symptoms of knee OA (P ≤ .001). There were no statistically detectable differences between the flavocoxid and naproxen groups with respect to any of the outcome variables. Similarly, there were no statistically detectable differences between the groups with respect to any adverse event, although there was a trend toward a higher incidence of edema and nonspecific musculoskeletal discomfort in the naproxen group. In this short-term pilot study, flavocoxid was as effective as naproxen in controlling the signs and symptoms of OA of the knee and would present a safe and effective option for those individuals on traditional nonsteroidal anti-inflammatory drugs or cyclooxygenase-2 inhibitors. A low incidence of adverse events was reported for both groups.  相似文献   
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