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11.
Dual‐process theories have dominated the study of risk perception and risk‐taking over the last two decades. However, there is a lack of objective brain‐level evidence supporting the two systems of processing in every‐day risky behavior. To address this issue, we propose the dissociation between evaluative and urgent behaviors as evidence of dual processing in risky driving situations. Our findings show a dissociation of evaluative and urgent behavior both at the behavioral and neural level. fMRI data showed an increase of activation in areas implicated in motor programming, emotional processing, and visuomotor integration in urgent behavior compared to evaluative behavior. These results support a more automatic processing of risk in urgent tasks, relying mainly on heuristics and experiential appraisal. The urgent task, which is characterized by strong time pressure and the possibility for negative consequences among others factors, creates a suitable context for the experiential‐affective system to guide the decision‐making process. Moreover, we observed greater frontal activation in the urgent task, suggesting the participation of cognitive control in safe behaviors. The findings of this research are relevant for the study of the neural mechanisms underlying dual process models in risky perception and decision‐making, especially because of their proximity to everyday activities. Hum Brain Mapp 36:2853–2864, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
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This study evaluated the procedural and long-term outcome of infants who underwent atrial septostomy while awaiting transplant. The results suggest that septostomy improved outcome in these patients although infants needing a transseptal perforation were at higher risk.  相似文献   
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Abstract:  HSCT associated morbidity and mortality is usually attributed to high-dose chemotherapy/radiotherapy regimens used for conditioning. Glutamine (Gln), a conditionally essential amino acid during severe catabolic states, has been shown to have favorable effects in patients with malignancies and in those undergoing HSCT. However, controversy exists regarding its routine use. Studies in children investigating gln supplementation are very limited. In the present study, including 21 gln-supplemented and 20 control pediatric patients, gln supplementation was shown to reduce the duration of fever and decrease the incidence of SOS during the HSCT course. In addition, a decrease in drug-related toxicity and a trend toward reduced incidence of severe mucositis were observed.  相似文献   
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OBJECTIVE: Surgical aortic valvotomy has a long history of providing excellent palliation for aortic stenosis in infancy and childhood. The fate of aortic valve repairs for dominant aortic regurgitation in this same age group is considerably less clear. METHODS: From 1990 to 2000, a total of 21 patients underwent aortic valve repair for aortic regurgitation at our institution. Seventeen patients were younger than 17 years at the time of repair (3-17 years, mean 8.1 +/- 3.7 years). Of these 17 children, 6 (35%) had bicuspid valves and 11 (65%) had tricuspid valves. Type of repair varied with valve type, but repair generally consisted of commissure resuspension, partial commissure closure, triangular resection of redundant leaflets, or some combination. RESULTS: There were no deaths. Follow-up ranged from 1 to 11 years (mean 5.3 +/- 2.4 years). At present 3 of 17 (17.6%) have mild aortic regurgitation according to echocardiography and 6 (35.2%) have moderate aortic regurgitation. In 8 of 17 cases (47.1%) the repair clearly failed, requiring reoperation from 0.5 to 73 months after the original operation (mean 18.9 months). Reoperation consisted of 6 Ross procedures and 2 mechanical aortic valve replacements. There were no deaths at the secondary operation. CONCLUSION: Aortic valve repair in children with a dominant feature of aortic insufficiency tended to fail progressively and at a high rate. Leaflet thickening was associated with higher risk of repair failure in this series. The threshold for aortic valve replacement should remain low.  相似文献   
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Although patients with systemic lupus erythematosus (SLE), especially those with antiphospholipid antibodies, have a high incidence of arterial and venous thrombotic manifestations, renal infarction has been rarely reported in these patients and is probably underestimated. A 9-year-old boy with renal infarction, diagnosed by computed tomography and scintigraphy, is described. Initially he complained of severe flank pain; he had no urinary abnormalities and his blood pressure was normal. No evidence of systemic disease was found. He responded well to antibiotic treatment without the need for immunosuppressive therapy. In subsequent years he presented a spectrum of clinical symptoms, including fever, malaise, arterial hypertension headache, and mononeuritis multiplex, accompanied by an increased erythrocyte sedimentation rate and transitory proteinuria. This suggested vasculitis involving peripheral vessels as well as the central nervous system. Treatment with oral prednisone and azathioprine led to remission. Four years after the renal infarction, the child presented with recurrence of systemic disease. The diagnosis of SLE was established, with positive antiphospholipid antibodies. The sudden appearance of severe unexplained flank pain should alert the clinician to a possible underlying renal vessel thrombosis. Renal venous thrombosis is probably much more common; however, renal arterial thrombosis and infarction in association with SLE with positive antiphospholipid antibodies should be added to the differential diagnosis.  相似文献   
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It is often stated that venovenous extracorporeal membrane oxygenation (VV ECMO) should not be used in inotrope dependent patients. It is our practice to use VV ECMO in most patients with respiratory failure even though many of these patients are receiving significant doses of inotropes. Our objective was to review the mode of ECMO in relation to precannulation doses of inotropes administered to neonates treated with ECMO for respiratory failure. Forty-three consecutive case notes were reviewed. Data were collected for basic demographic and ECMO parameters. Inotropic doses were converted to a single score for ease of comparison, with one point equivalent to 1 microg/kg/min dopamine. Forty-three neonates were studied; 37(86%) were treated with VV ECMO and 6 (14%) were treated with VA ECMO. Significant pre-ECMO inotropic support (score > 10) was present in 30 (70%) of the 43 cases. Of these patients, 26 were treated via VV ECMO with a survival rate of 84%, while 4 were treated with VA ECMO with a survival of 75%. Inotrope scores fell to nonsignificant levels (< 10) within 24 hours, regardless of ECMO mode. Mean arterial blood pressure remained above precannulation levels in both groups. VV ECMO allows safe treatment of neonatal respiratory failure in the presence of significant inotropic support. We recommend VV ECMO for neonatal respiratory failure in all cases except where double lumen cannulation is impossible or when septic shock is refractory to inotropic support (i.e., mean blood pressure < 35 mm Hg despite inotrope score of > 100).  相似文献   
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Several strains of Bacillus sphaericus (Neide) (Bsph), a spore-forming bacterium that produces potent mosquitocidal toxins, have been widely used against mosquito larvae globally. In some locations in the field and in the laboratory, moderate to high levels of resistance in Culex pipiens complex mosquito larvae to Bsph have been reported. Practical strategies for dealing with the resistance problem and more importantly to delay or possibly prevent development of resistance to Bsph in the first place are urgently needed. From published reports, we deduced that Bsph-resistant mosquito larvae are completely susceptible to Bacillus thuringiensis ssp. isreaelensis (Bti) and that there is no appearance of cross-resistance to Bti. On the basis of this information, we hypothesized that Bti offers a good potential for the management of resistance to Bsph, especially when it comes to delaying or preventing emergence of resistance. We conducted laboratory studies to see whether rotation of Bsph and Bti or mixture of both delays or prevents resistance development in Bsph-susceptible California Cx. quinquefasciatus. Development of resistance using Bsph alone increased after F15 and fluctuated slightly on further selections. Rotation of Bsph and Bti resulted in much higher level and rapid emergence of resistance to Bsph. However, selection with mixtures of Bti and Bsph for 36 generations showed no emergence of resistance. On the basis of this information, we believe mixtures have a good potential in delaying or preventing Bsph resistance.  相似文献   
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