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PURPOSE: The aim of this study was to quantify masseter muscle deformation during palpation and to discuss the clinical significance of muscle palpation using magnetic resonance imaging (MRI) and the image-analysis procedure. MATERIALS AND METHODS: Subjects were 10 male volunteers with a mean age of 26.8 years. MRIs were taken under two muscle conditions: compressed and noncompressed (control). By superimposing a compressed image on a noncompressed image, muscle deformation (the cross-sectional area, length of the surrounding area, thickness, circular convolution, compressed point, and anterior and posterior extension) was measured. RESULTS: The cross-sectional area of the masseter muscle was diminished by 14%, circular convolution of the muscle was reduced by 31%, the length of the surrounding area was enlarged by 11%, and the thickness of the muscle was reduced by 6.7 mm because of compressing. Thus, the masseter muscle was compressed. An uneven stretch of the muscle caused by compression was observed at the same time. The anterior portion of the masseter muscles extended on average 10%, with great individual differences. On the other hand, posterior extension (3%) and its individual differences were small. CONCLUSION: The method used made it possible to quantify masseter muscle deformation. By compressing, the masseter muscles were deformed especially in the anterior direction but with great individual differences.  相似文献   
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The effects of silkworm hemolymph, , on the frequency of hemocyte-binding were studied using the scanning electron microscopy ( SEM ) and a rosette assay with goose erythrocytes ( GRBC ). Hemocytes from the last instar larvae were able to bind to GRBC int he absence of hemolymph. Hemocytes type involved in sponteneous cytoadherence was mainly the granular cell, while both plasmatocyte and prohemocyte were also observed to adhere to GRBC. However, the frequency of these two hemocytes binding to GRBC was low compared with that of granular cells. Observations with the SEM showed that the presence of hemolymph increased the number of GRBC-binding hemocytes, especially the granular cells and plasmatocytes. Therefore, hemolymph probably had a significant role in the attachment of granular cells and plasmatocytes to foreign erythrocytes.  相似文献   
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Hirakawa H  Hayashida Y 《Hypertension》2006,48(6):1124-1129
Carbon monoxide (CO) is produced in the course of heme degradation from biliverdin by heme oxygenase (HO) in various tissues, including the central nervous system. Recent studies suggest the inhibition of HO activity increases arterial pressure mediated by the autonomic nervous system. The present study was designed to investigate the autonomic regulation of cardiovascular responses to inhibition of endogenous CO production by the HO inhibitor Zinc deuteroporphyrin 2, 4-bis glycol (ZnDPBG) by using direct sympathetic nerve recordings in conscious, chronically instrumented rats. ZnDPBG induced increases in mean arterial pressure (MAP) (P<0.05) and renal sympathetic nerve activity (RSNA) (P<0.05) but no significant change in heart rate (P>0.05) in intact rats. In atropine-treated rats, ZnDPBG also induced increases in MAP (P<0.05) and RSNA (P<0.05) but no change in heart rate (P>0.05). In sinoaortic denervated rats, ZnDPBG induced increases in MAP (P<0.05), heart rate (P<0.05), and RSNA (P<0.05). ZnDPBG shifted the baroreflex curve for RSNA upward and to the right, which was characterized by increases in the maximum and minimum response and midpoint pressure without altering the maximum gain. These results indicate that inhibition of HO activity within the central nervous system causes sympathoexcitation, resulting in an increase in arterial pressure. We conclude that the CO/HO system plays an important role in cardiovascular regulation by modulating sympathetic tone.  相似文献   
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In the treatment of arrhythmia, beta-blockers are mainly used to regulate the heart rate. However, beta-blockers are also known as drugs with an antiarrhythmic effect due to the suppression of sympathetic activity. We evaluated the antiarrhythmic effects of a highly selective beta(1)-blocker, bisoprolol, in patients with diurnal paroxysmal atrial fibrillation (P-AF). A total of 136 patients with symptomatic diurnal P-AF were enrolled. Patients were divided into a diurnal-specific P-AF group and a diurnal & nocturnal P-AF group, as well as into a bisoprolol single use group and a combined use group with an antiarrhythmic drug. The effects of bisoprolol were evaluated in 3 categories: subjective symptom improvement, quality of life (QOL) improvement, and elimination of P-AF episode in Holter electrocardiograms (ECGs). For patients with effective treatment, a long-term effect up to 24 months was evaluated. Five patients (3.7%) discontinued bisoprolol due to side effects. Following administration of bisoprolol, 109 patients (80%) experienced subjective symptom improvement, 103 patients (76%) experienced QOL improvement, and elimination of P-AF episodes in ECGs was observed in 84 patients (62%). The elimination rate of P-AF episodes in ECGs was higher in the diurnal P-AF group than in the diurnal & nocturnal P-AF group (P=0.042). There was no significant difference between the bisoprolol single use group and the combined use group. A long-term suppressive effect by bisoprolol was observed in 70 of 83 patients (84%). The results demonstrate that bisoprolol has an antiarrhythmic effect against sympathetic diurnal P-AF, improving subjective symptoms and QOL and eliminating P-AF episodes in ECGs.  相似文献   
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OBJECTIVES: To investigate the association between ambulatory blood pressure (BP) variables (level, short-term variability, circadian variation and morning pressor surge) and carotid artery alteration in a general population. METHODS: We measured ambulatory BP every 30 min in 775 participants (mean age 66.2 +/- 6.2 years, 68.8% women) from the Japanese general population. Short-term BP variability during the daytime and night-time were estimated as within-subject standard deviation of daytime and night-time BP, respectively. Circadian BP variation was calculated as the percentage decline in nocturnal BP. Morning pressor surge was defined as morning BP minus pre-waking BP. The extent of carotid artery alteration was evaluated as the average of common carotid intima-media thickness (IMT) and the presence of focal carotid plaque. RESULTS: Daytime and night-time BP values were more closely associated with carotid artery alteration than casual BP. With mutual adjustment for daytime and night-time BP, the latter (P < 0.0001) was more closely associated with IMT, which represents diffuse arterial thickening and arteriosclerosis, than daytime BP (P = 0.2). Night-time systolic BP variability was positively associated with carotid plaque (focal atherosclerotic lesions) independently of possible confounding factors, including night-time systolic BP (P = 0.01). A diminished nocturnal decline in systolic BP was associated with a greater IMT after adjustment for confounding factors (P = 0.03). A morning pressor surge was not associated with carotid artery alteration. CONCLUSION: Ambulatory BP levels and BP variability were closely associated with carotid artery alteration, suggesting that these parameters are independent risk factors or predictors of carotid artery alteration.  相似文献   
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Pancreatic ductal adenocarcinoma (PDAC) is a deadly malignancy that frequently metastasizes and that overexpresses transforming growth factor-beta s (TGF-beta s). To determine whether TGF-beta s can act to enhance the metastatic potential of PDAC, PANC-1 human pancreatic cancer cells were transfected with an expression construct encoding a soluble type II TGF-beta receptor (sT beta RII) that blocks cellular responsiveness to TGF-beta 1. When injected s.c. in athymic mice, PANC-1 clones expressing sT beta RII exhibited decreased tumor growth in comparison with sham-transfected cells and attenuated expression of plasminogen activator inhibitor 1 (PAI-1), a gene associated with tumor growth. When tested in an orthotopic mouse model, these clones formed small intrapancreatic tumors that exhibited a suppressed metastatic capacity and decreased expression of plasminogen activator inhibitor 1 and the metastasis-associated urokinase plasminogen activator. These results indicate that TGF-beta s act in vivo to enhance the expression of genes that promote the growth and metastasis of pancreatic cancer cells and suggest that sT beta RII may ultimately have a therapeutic benefit in PDAC.  相似文献   
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This study investigated the ability of adults with Asperger syndrome to recognize emotional categories of facial expressions and emotional prosodies with graded emotional intensities. The individuals with Asperger syndrome showed poorer recognition performance for angry and sad expressions from both facial and vocal information. The group difference in facial expression recognition was prominent for stimuli with low or intermediate emotional intensities. In contrast to this, the individuals with Asperger syndrome exhibited lower recognition accuracy than typically-developed controls mainly for emotional prosody with high emotional intensity. In facial expression recognition, Asperger and control groups showed an inversion effect for all categories. The magnitude of this effect was less in the Asperger group for angry and sad expressions, presumably attributable to reduced recruitment of the configural mode of face processing. The individuals with Asperger syndrome outperformed the control participants in recognizing inverted sad expressions, indicating enhanced processing of local facial information representing sad emotion. These results suggest that the adults with Asperger syndrome rely on modality-specific strategies in emotion recognition from facial expression and prosodic information.  相似文献   
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