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61.
Background: Whether procedural termination of persistent atrial fibrillation (AF) is necessary for optimal clinical efficacy still remains controversial. We sought to characterize the patients with persistent AF in whom procedural AF termination impacted an improved clinical outcome after ablation. Methods: We retrospectively assessed 132 patients (61.0 ± 9.3 years, 114 males) undergoing catheter ablation of persistent AF (duration 3 years, median). A stepwise ablation approach including pulmonary vein isolation and atrial substrate ablation targeting complex fractionated and high‐frequency electrograms was performed with desired endpoint of AF termination. Results: Overall, 90 patients (68%) were free from recurrent arrhythmias at 20 ± 11 months of follow‐up after one or two procedures. The left atrial diameter and continuous AF duration according to medical history were associated with the outcome (P = 0.002 and P< 0.001, respectively). In multivariate Cox regression analysis, the continuous AF duration was the only independent predictor of recurrent arrhythmias (hazard ratio 1.17, 95% confidence interval 1.10–1.23, P < 0.001). In patients with AF duration of ≥3 years, the clinical success was comparable regardless of whether AF termination was achieved or not (log‐rank, P = 0.27). In the remaining patients with AF duration of <3 years, procedural AF termination was associated with a higher arrhythmia‐free rate than when AF was sustained after ablation (log‐rank, P = 0.023). Conclusion: Extensive ablation to terminate AF might not be warranted in patients with a longer AF duration. On the contrary, procedural AF termination could be associated with maintenance of sinus rhythm in patients with a shorter AF duration with a less proarrhythmic substrate. (PACE 2012;35:1436–1443)  相似文献   
62.
The migration of isotopically-labelled challenge parasites of Schistosoma mansoni in naive CBA/Ca mice, and CBA/Ca mice vaccinated 4 weeks previously with about 600 radiation-attenuated cercariae, has been followed by means of compressed organ autoradiography. In naive mice, only 16% of the challenge parasites failed to migrate from the skin to the lungs, whereas up to half of the individuals that succeeded in reaching the pulmonary vasculature did not move on to the liver. The tracking technique thus revealed a total loss of 58% of the challenge parasites, which correlated well with the fact that only 50% of the challenge was recovered as adult worms by retrograde perfusion of the hepatic portal system. Challenge migration in vaccinated mice initially proceeded more slowly than in naive mice, but peak numbers of foci were eventually recorded in the lungs on the same day in both groups of individuals. We did not therefore recognize a delay in parasite migration in vaccinated mice. In the present experiments, 58.5% of the challenge failed to reach the lungs of vaccinated rodents, and 25% of those parasites that did attain the pulmonary vasculature were not recruited to the liver. The tracking technique thus accounted for a total loss of 83.5% of the parasites, which again correlated well with the fact that we recovered only 22% of the challenge as adult worms at portal perfusion. The data presented here prove conclusively that the major phase of immune-dependent challenge elimination in vaccinated CBA/Ca mice occurs in the cutaneous tissues, and that only a small proportion of the parasites are lost in the lungs. These data are entirely consistent with those we have published elsewhere for the CBA/Ca mouse using a multiplicity of different techniques; they differ however, from results reported by others for the C57 Black strain of mouse. Possible reasons for these discrepancies are discussed.  相似文献   
63.
Administration of dextran sulphate sodium to animals induces acute colitis characterized by infiltration of large numbers of neutrophils into the colonic mucosa, which histologically resembles human active ulcerative colitis. It has been reported that neutrophils and the reactive oxygen metabolites produced by them are involved in the progress of ulcerative colitis. This study was intended to clarify their roles by using this animal model. First, possible sources and species of reactive oxygen metabolites were determined using luminol-dependent chemiluminescence with addition of enzyme inhibitors and reactive oxygen metabolite scavengers. Next, to examine whether neutrophils and hypochlorous acid derived from them contribute to tissue injury, we administered RP-3, a monoclonal antibody capable of selectively depleting neutrophils, and taurine, a hypochlorous acid scavenger, to rats treated with dextran sulphate sodium. Addition of azide, taurine, catalase, superoxide dismutase and dimethyl sulphoxide into colonic mucosal scrapings significantly inhibited chemiluminescence production, but allopurinol and indomethacin had no effects. These results suggest that excessive hypochlorous acid, hydrogen peroxide, superoxide anion and hydroxyl radical are generated by the inflamed colonic mucosa. Intraperitoneal injections of RP-3 significantly suppressed bleeding, tissue myeloperoxidase activity, chemiluminescence production and erosion formation. On the other hand, administration of taurine tended to inhibit bleeding and erosion formation to some extent, although it could not significantly suppress them. These data suggest that neutrophils play an important role in the development of this colitis and that hypochlorous acid might be one of the causes of tissue injury induced by neutrophils.  相似文献   
64.
Objectives: We evaluated the effectiveness of antimuscarinic treatment on disease‐specific and generic quality of life (QoL) in females with clinically diagnosed overactive bladder (OAB) by prospectively analyzing improvements in the overactive bladder symptom score (OABSS) and the Rand Medical Outcomes Study 36‐Item Short Form Health Survey (SF‐36). Methods: We prospectively recruited newly diagnosed female patients with OAB. Pretreatment disease‐specific symptoms were documented, and generic QoL questionnaires were administered. All subjects received solifenacin 5 mg/day for >8 weeks. Symptoms and general health‐related QoL (HRQoL) were assessed using the OABSS and SF‐36, respectively. Other objective variables, such as maximum urinary flow rate and postvoid residual urine volume, were also evaluated. Results: Seventy‐eight subjects met all inclusion criteria and no exclusion criteria. After 8 weeks, the mean OABSS decreased by approximately 50% compared with baseline (from 9.1 ± 2.8 to 4.5 ± 3.6). All individual scores in OABSS improved after administration of solifenacin. Before treatment, the scores of the study subjects in all SF‐36 domains were significantly worse than the age‐ and gender‐adjusted Japanese national norms (P < 0.01), except the vitality (VT) scale. Intra‐group comparisons between age groups showed worse mental health (MH) scores in all age groups. In the OAB group, three mean SF‐36 scales (physical function [PF], VT, and MH) significantly improved after treatment. Conclusion: Treatment of OAB with solifenacin is associated with significant improvement in generic HRQoL and disease‐specific symptoms at 8 weeks after drug administration. Particularly for generic HRQoL as measured by the SF‐36, solifenacin treatment effectively improves three SF‐36 scores: PF, VT, and MH.  相似文献   
65.
AF Ablation in HD Patients . Introduction: It is not common for patients on chronic hemodialysis (HD) to undergo catheter ablation of atrial fibrillation (AF). We aimed to show the outcomes of AF ablation in the HD patients. Methods and Results: Thirty HD patients who underwent pulmonary vein (PV) isolation for drug refractory paroxysmal AF were retrospectively studied, and their AF recurrence free rate and frequency of periprocedural complications were compared to 60 age‐ and gender‐matched control patients not requiring HD. A nonirrigated ablation catheter was used in both patient groups. During a mean follow‐up period of 821 ± 218 days, 16 (54%) of the HD patients remained free from AF recurrence without any antiarrhythmic agents versus 47 (78%) of the control patients with an initial ablation (P = 0.013). A second ablation procedure was performed in 12 patients with an AF recurrence, and consequently 20 (67%) of the HD patients were in sinus rhythm compared to 53 (88%) of the controls during a follow‐up duration of 747 ± 221 after the last ablation (P = 0.012). Bleeding from the venipuncture site requiring a prolonged hospital stay was identified in 2 HD patients and 1 control subject, while no life‐threatening complications were observed in either patient group. Conclusion: Although the success rate of the PV isolation in HD patients was far from satisfactory, it may be considered as one of the therapeutic options for them. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1289‐1294, December 2012)  相似文献   
66.
Faecal clearance of alpha 1-antitrypsin was measured in patients with ulcerative colitis and Crohn's disease and compared with disease activity and markers of protein-calorie malnutrition. Patients with active ulcerative colitis and Crohn's disease showed elevated clearance of alpha 1-antitrypsin and clearance declined in most patients with induction of remission. However, even with inactive disease, elevated protein loss persisted in some patients, presumably reflecting residual inflammation in the intestinal mucosa. There was a significant correlation between clearance of alpha 1-antitrypsin and serum levels of retinol-binding protein and transferrin in patients with ulcerative colitis and with retinol-binding protein in patients with Crohn's disease. Clearance of alpha 1-antitrypsin reflects disease activity in inflammatory bowel disease and correlates with serum levels of rapid-turnover proteins such as retinol-binding protein and transferrin, which are markers for the presence of protein-calorie malnutrition.  相似文献   
67.
RADIAL COMPONENT OF CENTRAL MYELIN IN NORMAL AND QUAKING MICE   总被引:1,自引:0,他引:1  
Radial component of myelin sheaths was investigated in C57BL and quaking mice. In immature myelinated fibres of C57BL mice, more than one group of radial component were observed in the several regions of myelin sheaths while in mature fibres, one group of radial component was localized between the internal mesaxon and outer tongue process which were situated within 90° of each other. In thinly myelinated fibres of adult quaking mice, numerous groups of radial component were found at random distance and directions but they were always closely related to the cytoplasmic islands of oligodendroglia. Even in quaking mice, small well myelinated fibres showed normal mature pattern of radial component. Possible functional significance of radial component was briefly discussed.  相似文献   
68.
中国人胆固醇酯转运蛋白(CETP)基因的变异   总被引:1,自引:0,他引:1  
CETP是反向胆固醇转运的重要载体。反向胆固醇转运是将胆固醇从周围组织向肝脏转运的过程。近来发现,CETP基因的变异影响这一过程,引起血脂水平的变化。CETP基因位于第16号染色体长臂上(16ql3),全长25kb。AKITA等1994年首次报道了日本人中CETP基因变异的情况,突变的...  相似文献   
69.
Precutaneous transcatheter closure technique of a coronary artery fistula with a detachable balloon was performed for a 14 year old male student. Complete closure of the fistula without any complications was confirmed by angiography after the procedure. When the patient underwent a second angiography 6 months after the closure, it was confirmed that the position of the balloon had not changed, that the interruption of the flow of the fistula had been maintained and that the diameter of the left coronary artery and the fistula were reduced. Percutaneous closure technique using a detachable balloon may become the primary treatment for a coronary artery fistula in place of surgical ligation.  相似文献   
70.
Diarrheal disease is the major cause of childhood morbidity in developing countries. Although malnutrition is known as a risk factor for severe gastroenteritis, the role of enteric pathogens in the clinical severity is unclear. The present study was conducted in well nourished Ghanaian preschool children during a 3 month period of the rainy season to assess the relationship between enteric pathogens and severe gastroenteritis. Two hundred and twenty-five children with acute gastroenteritis and 64 age-matched control children were prospectively examined for the severity of dehydration and enteric pathogens in their stools. Of the 225 children with gastroenteritis, 69.8% (157/225) had mild dehydration and 30.2% (68/225) had severe dehydration. Bacteria were similarly isolated in stool samples from children with mild and severe dehydration and controls. Rotavirus accounted for 20.6% of children with severe dehydration and was more often isolated in stools from patients with severe dehydration than those from controls. Furthermore, the mixed infections associated with rotavirus and bacteria were more often found in patients with severe dehydration than those with mild dehydration or controls. Parasites were similarly found at low incidences among the three groups. The present study implied that rotavirus was more responsible for severe gastroenteritis than bacteria or parasites. However, factors other than enteric pathogens must be sought in a considerable number of severe cases. A large scale study throughout a year is recommended to obtain more precise information that would reflect the seasonal variation of rotavirus infections.  相似文献   
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