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41.
Using serial intravascular ultrasound (IVUS), integrated-backscatter IVUS, and optical coherence tomography, we observed rapidly progressive cardiac allograft vasculopathy (CAV) and donor-transmitted plaque in the left anterior descending artery. Late-phase everolimus-resistant CAV had a rapidly progressive course (maximal intimal thickness [MIT] increased by 0.5 mm between years 3 and 4 after cardiac transplantation, from MIT growth <0.5 mm at year 1). Conversely, the donor-transmitted plaque grew slowly (0.1 mm increase during the same period). Tissue characteristics in the 2 segments were also different; CAV had eccentric, noncalcified, and lipid-rich components and was associated with macrophage accumulation, whereas donor-transmitted atherosclerosis presented with typical features of atherosclerosis (ie, fibrocalcific plaque). CAV with late-phase progression involves everolimus resistance and features of vulnerable plaques seen in nontransplantation patients and is independent of donor-transmitted atherosclerosis.  相似文献   
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Summary The electrophysiological effects of flecainide acetate (3×10–6 M) on stretched atrial tissue were investigated using guinea-pig left atrial muscle fibers. Before stretching, the resting membrane potential was not affected by flecainide at 1 Hz, although the overshoot potential (Eov) and the action potential duration at 50% repolarization (APD50) were slightly but significantly decreased by 2±1 mV and 2±1 msec, respectively. The effective refractory period (ERP) was increased by 3±1 msec. The reduction of max was 20.6±1.2%. The half-maximum potential (Vh) of the relationship between max and the resting potential was shifted to become more negative by flecainide (from –60.6±2.1 mV to –63.2±1.7 mV). After 90–120 min of washout with drug-free Tyrode's solution, the tissue was mechanically stretched to 150% of its slack length. Stretching significantly decreased the max by 16.9±3.1%, along with a slight but significant increase in ERP (3±1 msec) and shifted Vh to become more negative (from –60.6±2.1 to –63.1±1.8 mV). In the presence of flecainide, max further decreased by 20.2±2.6%, and Vh shifted from –63.1±1.8 to –65.0±1.5 mV. Comparison with the control unstretched fibers showed that flecainide significantly decreased max by 34.0±2.7%, reduced the resting membrane potential by 3±1 mV, decreased Eov by 4±1 mV, and shifted Vh from –60.6±2.1 to –65.0±1.5 mV, while the APD50 and ERP did not change. In conclusion, the reduction of max in the presence of flecainide was much greater in the stretched atrial muscle fibers than in the unstretched fibers, because the max-resting potential relationship was shifted towards more negative potentials by both flecainide and stretching. These results suggest that flecainide exerts a stronger antiarrhythmic action on stretched atrial muscle fibers than on normal fibers.  相似文献   
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Early-onset sarcoidosis (EOS) and inheritable Blau syndrome (BS) share characteristic clinical features of juvenile-onset systemic granulomatosis syndrome that mainly affects skin, joints, and eyes. However, no direct evidence has been shown for the possible common origin of these 2 diseases. Recent discovery of CARD15 mutations in BS families encouraged us to investigate similar CARD15 mutations in EOS patients. Among 10 EOS cases retrospectively collected in Japan, heterozygous missense mutations were found in 9 cases; 4 showed a 1000C>T (R334W in amino acid change) that has been reported in BS, 4 showed novel 1487A>T (H496L), 1538T>C (M513T), 1813A>C (T605P), and 2010C>A (N670K), and 1 case showed double 1146C>G (D382E)/1834G>A (A612T) mutations on different alleles. All 6 of these variants of CARD15 showed increased basal nuclear factor (NF)-kappaB activity. These findings indicate that the majority of EOS and BS cases share the common genetic etiology of CARD15 mutations that cause constitutive NF-kappaB activation.  相似文献   
46.
We describe here a thoracic esophageal cancer with an unusual type of duplicated inferior vena cava. A 58-year-old man was referred to our hospital because a tumor in his lower esophagus had been identified by endoscopy and radiology. Computed tomography scans showed an unusual type of duplicated inferior vena cava characterized by both common iliac veins flowing back into the left-sided inferior vena cava, which drained into the azygos vein, whereas the right-sided one had no drainage. Esophagectomy was performed 3 weeks later after preoperative chemotherapy. Because the patient could have developed thrombosis of the left-sided inferior vena cava and severe hypotension caused by decreased venous return to the heart if the azygos vein had been severed, the azygos vein was preserved. Thus, when performing surgery for thoracic esophageal cancer, the surgeon should check for a duplicated inferior vena cava and preserve the azygos vein if necessary.  相似文献   
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Verbal irony conveys various emotional messages, from criticism to humor, that differ from the meaning of the actual words. To understand irony, we need conceptual knowledge of irony in addition to an understanding of context. We investigated the neural mechanism of irony comprehension, focusing on two overlooked issues: conceptual knowledge and emotional response. We studied 35 healthy subjects who underwent functional MRI. During the scan, the subject examined first‐person‐view stories describing verbal interactions, some of which included irony directed toward the subject. After MRI, the subject viewed the stories again and rated the degree of irony, humor, and negative emotion evoked by the statements. We identified several key findings about irony comprehension: (1) the right anterior superior temporal gyrus may be responsible for representing social conceptual knowledge of irony, (2) activation in the medial prefrontal cortex and the right anterior inferior temporal gyrus might underlie the understanding of context, (3) modulation of activity in the right amygdala, hippocampus, and parahippocampal gyrus is associated with the degree of irony perceived, and (4) modulation of activity in the right dorsolateral prefrontal cortex varies with the degree of humor perceived. Our results clarified the differential contributions of the neural loci of irony comprehension, enriching our understanding of pragmatic language communication from a social behavior point of view. Hum Brain Mapp 35:1167–1178, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
48.
Quality of life (QOL) has been defined in many ways, and these definitions usually emphasize happiness and satisfaction with life. Health‐related problems are known to cause lower QOL. However, the neural mechanisms underlying individual differences in QOL measured by questionnaire (QOLMQ) in young healthy subjects are unknown. QOL is essential to our well‐being, and investigation of the neural mechanisms underlying QOL in uncompromised subjects is obviously of great scientific and social interest. We used voxel‐based morphometry to investigate the association between regional gray matter volume (rGMV) and QOLMQ across the brain in healthy young adults (age, 21.4 ± 1.8 years) men (n = 88) and women (n = 68) in humans. We found significant negative relationships between QOLMQ and rGMV in a region in the left rostrolateral prefrontal cortex and regions in the dorsal part of the anterior cingulate gyrus and contingent cingulate regions. These findings show that structural variations in regions associated with processing of negative emotions such as fear and anger as well as those associated with evaluation of internally generated information are associated with QOLMQ. These findings suggest that these processes might be related to QOLMQ in healthy young adults. Hum Brain Mapp 35:1834–1846, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
49.
Most inhabitants of Tohoku district suffer from chronic fatigue after the 2011 Great East Japan Earthquake. Chronic fatigue following disasters may lead to serious illness, even death. Posttraumatic growth appears to counteract fatigue. We predicted that the chronic fatigue would be inversely related to the posttraumatic growth factor “relating to others,” as represented by mutual helping and a strong sense of connection with humanity. Young 59 healthy volunteers, residing in Miyagi prefecture, were recruited 3 months after the disaster. We measured the subjects? total scores on the Japanese version of the Checklist Individual Strength questionnaire (CIS), the Trait Anxiety (T-A) subscale of the State–Trait Anxiety Inventory (STAI), the Center for Epidemiologic Studies Depression Scale (CES-D), and four subscores on the posttraumatic growth inventory (PTGI). Stepwise regression analyses were conducted with score on the CIS as the dependent variable and other scores as independent variables. Scores on the “relating to others” factor of the PTGI showed a significant negative relationship with the CIS score, whereas the scores on the T-A subscale of the STAI and the CES-D were positively related to the CIS score. Human ties and mutual help were negatively related to the degree of the chronic fatigue.  相似文献   
50.
Because vaccination is an effective means to protect humans from influenza viruses, extensive efforts have been made to develop not only new vaccines, but also for new adjuvants to enhance the efficacy of existing inactivated vaccines. Here, we examined the adjuvanticity of synthetic hemozoin, a synthetic version of the malarial by-product hemozoin, on the vaccine efficacy of inactivated whole influenza viruses in a mouse model. We found that mice immunized twice with hemozoin-adjuvanted inactivated A/California/04/2009 (H1N1pdm09) or A/Vietnam/1203/2004 (H5N1) virus elicited higher virus-specific antibody responses than did mice immunized with non-adjuvanted counterparts. Furthermore, mice immunized with hemozoin-adjuvanted inactivated viruses were better protected from lethal challenge with influenza viruses than were mice immunized with non-adjuvanted inactivated vaccines. Our results show that hemozoin improves the immunogenicity of inactivated influenza viruses, and is thus a promising adjuvant for inactivated whole virion influenza vaccines.  相似文献   
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