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Circulating von Willebrand factor in inflammatory bowel disease.   总被引:4,自引:0,他引:4       下载免费PDF全文
Raised circulating von Willebrand factor is a recognised marker of vascular injury. To evaluate the role of vascular injury in the pathogenesis of inflammatory bowel disease, serum von Willebrand factor in Crohn's disease, ulcerative colitis, confirmed bacterial diarrhoea, and healthy subjects was measured. von Willebrand factor values were raised in 9/14 patients (p = 0.007) with active Crohn's disease, 15/28 (p = 0.0004) with inactive Crohn's disease, 16/23 (p = 0.0003) with active ulcerative colitis, 9/27 (p = 0.04) with inactive ulcerative colitis, and 15/17 (p = 0.0001) patients with bacterial diarrhoea. Serum von Willebrand factor was unrelated to disease activity in Crohn's disease but was significantly raised in active (p = 0.02) compared with inactive ulcerative colitis. In contrast to controls, the detection of von Willebrand factor from inflammatory bowel disease sera and that from fractured endothelial cells was significantly inhibited by the reducing agent, dithiothreitol, suggesting the presence of an additional dithiothreitol sensitive form of the molecule derived from injured endothelial cells in inflammatory bowel disease. That serum von Willebrand factor is raised in quiescent as well as active Crohn's disease is compatible with the proposal that vascular injury is a fundamental abnormality in this disorder. The raised von Willebrand factor values in active inflammatory bowel disease and bacterial diarrhoea could be caused by either vascular injury, occurring secondary to bowel inflammation, or to an acute phase response resulting from endothelial cell stimulation by mediators released during the inflammatory process. Raised circulating von Willebrand factor could contribute to the increased risk of thrombosis associated with active inflammatory bowel disease.  相似文献   
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BackgroundThe detection of novel health-care-associated infections as early as possible is an important public health priority. However, no evidence base exists to guide the design of efficient and reliable surveillance systems. Here we address this issue in the context of a novel pathogen spreading primarily between hospitals through the movement of patients.MethodsUsing hospital admission data from the year 2007, we modelled the spread of a pathogen among a network of hospitals connected by patient movements using a hospital-based susceptible-infectious model. We compared the existing surveillance system in Scotland with a gold standard (a putative optimal selection algorithm) to determine its efficiency and to see whether it is beneficial to alter the number and choice of hospitals in which to concentrate surveillance effort.FindingsWe validated our model by demonstrating that it accurately predicted the risk of meticillin-resistant cases of Staphylococcus aureus bacteraemia in hospitals in Scotland in 2007. Furthermore, the model predicted that relying solely on the 29 (out of 182) sentinel hospitals that currently contribute most of the national surveillance effort results in an average detection time (time until first appearance of the pathogen in a hospital) of 117 days. This detection time could be reduced to 87 days by optimal selection of the same number of hospitals. Alternatively, the same detection time (117 days) can be achieved with just 22 optimally selected hospitals. Increasing the number of sentinel hospitals to 38 (teaching and general hospitals) reduced detection time by 43 days; a decrease to seven sentinel hospitals (all teaching hospitals) increased detection time substantially to 268 days.InterpretationOur results show that the present surveillance system used in Scotland is not optimal in detecting novel pathogens compared with a gold standard. However, efficiency gains are possible by better choice of sentinel hospitals, or by increasing the number of hospitals involved in surveillance. Similar studies could be used elsewhere to inform the design and implementation of efficient national, hospital-based surveillance systems that achieve rapid detection of novel health-care-associated infections for minimum effort.FundingThis research received funding from the European Union Seventh Framework Programme (FP7-HEALTH-2011-single-stage): Evolution and Transfer of Antibiotic Resistance (EvoTAR).  相似文献   
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The concentrations of 13 elements were determined in the muscle, liver, intestine, kidney, and gonads of cultured and wild carp caught at two sites in Lake Kasumigaura, Japan, between September 1994 and September 1995. Despite having a reputation for being heavily polluted, the carp were not heavily burdened with metals. Our results suggest that despite their dietary differences, the wild and cultured fish were accumulating and distributing metals in the same manner and that aquaculture practices are not increasing metal concentrations in these fish. Metal concentrations were lowest in muscle, and did not exceed established quality standards for fish. The differences in metal concentrations between cultivated and wild carp are negligible and should pose no health problems for consumers of either type of fish.  相似文献   
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Samples of the muscle and liver of tilapia (Oreochromis mossambicus) obtained from the five reservoirs in four catchments in southern Sri Lanka in 1998 were analyzed for 16 elements: As, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sr, and Zn by inductively coupled plasma emission spectrophotometry, and Hg by atomic absorption spectrophotometry. The concentrations of Cr, Ni, and Pb were below the detection limits of the instrumental techniques employed in all samples. The elements As, Ca, Co, Cu, Fe, Hg, K, Mg, Mn, Na, Sr, and Zn were detected in the muscle and liver tissue, with Cd detected in some liver samples. There were no statistically significant differences between the individual concentrations of any of the metals and the site from which the tilapia were collected (P>0.05). Furthermore, no statistically significant correlations were found between total length of fish and metal concentration. No elements were found at concentrations of toxicological concern. However, a principal component analysis suggests that the populations of tilapia in the reservoirs may be exposed to different regimes of metals, possibly associated with different catchment land-use patterns.  相似文献   
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van Schaik  JP; Hawkins  IF  Jr 《Radiology》1985,155(3):829-830
A new technique is described for reversing the direction of the catheter tip during translumbar aortography, without the need for partial withdrawal of the catheter from the aortic lumen. The method ensures optimal delivery of contrast medium at the desired level, while avoiding the risk of retroperitoneal bleeding or dislodgement during catheter manipulation.  相似文献   
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The use of the Bene-Anthony Family Relations Test is described and illustrated by three examples of child abuse. This test should be considered in the investigation of definite or suspected cases of abuse and as part of the preparation of court evidence.  相似文献   
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