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排序方式: 共有212条查询结果,搜索用时 250 毫秒
131.
DH Kim H Wit M Thurston M Long GF Maskell MJ Strugnell D Shetty IM Smith NP Hollings 《The British journal of radiology》2021,94(1122)
Objectives:Small bowel obstruction is a common surgical emergency which can lead to bowel necrosis, perforation and death. Plain abdominal X-rays are frequently used as a first-line test but the availability of immediate expert radiological review is variable. The aim was to investigate the feasibility of using a deep learning model for automated identification of small bowel obstruction.Methods:A total of 990 plain abdominal radiographs were collected, 445 with normal findings and 445 demonstrating small bowel obstruction. The images were labelled using the radiology reports, subsequent CT scans, surgical operation notes and enhanced radiological review. The data were used to develop a predictive model comprising an ensemble of five convolutional neural networks trained using transfer learning.Results:The performance of the model was excellent with an area under the receiver operator curve (AUC) of 0.961, corresponding to sensitivity and specificity of 91 and 93% respectively.Conclusion:Deep learning can be used to identify small bowel obstruction on plain radiographs with a high degree of accuracy. A system such as this could be used to alert clinicians to the presence of urgent findings with the potential for expedited clinical review and improved patient outcomes.Advances in knowledge:This paper describes a novel labelling method using composite clinical follow-up and demonstrates that ensemble models can be used effectively in medical imaging tasks. It also provides evidence that deep learning methods can be used to identify small bowel obstruction with high accuracy. 相似文献
132.
The enigma of pyloric stenosis. Some thoughts on the aetiology 总被引:1,自引:0,他引:1
IM Rogers 《Acta paediatrica (Oslo, Norway : 1992)》1997,86(1):6-9
A theory is advanced about the cause of pyloric stenosis of infancy (PS). Developmental changes will conspire to produce pathogenetic gastric hyperacidity within the first 4 weeks of life in babies who develop PS. The prime cause will be an increased gastric acidity due to a genetically determined supernormal parietal cell mass. This theory satisfactorily explains many known clinical features. 相似文献
133.
Red Light Phototherapy Alone Is Effective for Acne Vulgaris: Randomized, Single-Blinded Clinical Trial 总被引:1,自引:0,他引:1
BACKGROUND: Recently, a demand for safe and effective treatment of acne has been increasing. Although visible light has attracted attention as a new option, the effect of red light alone has not yet been evaluated. OBJECTIVES: The objective was to assess the efficacy of red light phototherapy with a portable device in acne vulgaris. METHODS: Twenty-eight volunteers with mild to moderate acne were treated with portable red light-emitting devices in this split-face randomized trial. The right or left side of the face was randomized to treatment side and phototherapy was performed for 15 minutes twice a day for 8 weeks. Clinical photographs, lesion counts, and a visual analog scale (VAS) were used to assess each side of the face at baseline and Weeks 1, 2, 4, and 8, and a split-face comparison was performed. RESULTS: The percent improvement in noninflammatory and inflammatory lesion counts of the treated side was significant compared to the control side (p<.005). VAS decreased from 3.9 to 1.9 on the treatment side and the difference between the treatment and control sides was significant at Week 8 (p<.005). CONCLUSIONS: This study shows that red light phototherapy alone can be a new therapeutic option for acne vulgaris. 相似文献
134.
D Anil Kumar RN Suresh Kumar PN Rao S Chandran VR Pillai CG Venkatachalam YA Nazer T Cartmill IM Rao I. M. Rao 《Indian Journal of Thoracic and Cardiovascular Surgery》2003,19(2):102-107
Background: There has been a rekindling of interest in alternatives to conventional two patch technique for the repair of complete atrioventricular
septal defect in infancy in the recent past. We applied the simplified single patch technique to 15 consecutive infants and
herein report our intermediate term results.
Methods: Between March 1998 and September 2001, fifteen patients underwent repair of complete atrioventricular septal defect with
this technique (mean age 6 months, mean weight 5.4 kg). Downs syndrome was present in 11 patients. Repair was done in all
patients by direct suturing of the common atrioventricular valve leaflets to the crest of the ventricular septum irrespective
of the size of the ventricular septal component. The cleft in the anterior mitral leaflet was closed in all patients. The
atrial septal component was closed by a pericardial patch.
Results: There was no mortality. There were no pulmonary arterial hypertensive crises or heart block. The mean follow up was 13.2
months. One patient underwent mitral valve replacement after one year due to severe mitral regurgitation. The remaining fourteen
patients had no significant mitral regurgitation, residual ventricular septal defect or left ventricular outflow tract obstruction
on echocardiography.
Conclusion: Simplified single patch technique is an easily reproducible method for surgical repair of complete atrioventricular septal
defect. It is less time consuming and minimises ischaemic time. Atrioventricular valve function is preserved and there is
no incidence of obstruction to left ventricular outflow tract. The intermediate term results are encouraging.
Presented in the poster session of the 37th Annual Meeting of Association for European Paediatric Cardiology (AEPC) at Porto, Portugal, May 2002 相似文献
135.
136.
Collecting exhaled breath condensate (EBC) has become a frequently used method in respiratory researches to date. Through this method we can sample airway surface liquid non-invasively by streaming the exhaled breath through a cooled chamber and after we examine the fluid deposited on the wall of the condenser. The sample contains several mediators, biomarkers. The pH of the condensate is one of the most important markers measured in the EBC. Measuring the pH is easy, cheap and it is in the optimal range, there is no problem with the detection limit. The uncertainty of the pH assays is derived from the instability of the EBC pH which results from the altering carbon-dioxide concentration. Many articles have been published on EBC pH in different airway diseases. Acidification of the condensates has been described in bronchial asthma (especially in acute exacerbations), chronic obstructive lung disease (COPD). Due to the steroid treatment the pH has increased in both cases. In patients with bronchiectasis, cystic fibrosis and in chronic cough (bronchial asthma, gastro-esophageal reflux, postnasal drip, and unknown origin) the pH of EBC was also lower. Acidification of the airways in different diseases can play a role in the pathomechanism, and its indicator, the EBC pH might help managing patients with airway diseases. 相似文献
137.
Alteration of lipid composition of hepatic membranes associated with manganese-bilirubin induced cholestasis 总被引:3,自引:0,他引:3
Summary— One hypothesis concerning the pathogenesis of manganese-bilirubin (Mn-BR)-induced cholestasis is that the molecular organization of the bile canalicular membrane is altered. The purpose of the present study was to evaluate lipid composition and fluidity of hepatic membranes during cholestasis in male Sprague-Dawley rats. To induce cholestasis, manganese (Mn, 4.5 mg/kg, intravenously [iv]) was given IS min before bilirubin (BR, 25 mg/kg, iv). The rats were killed 30 min after BR injection, at which time bile flow was decreased by approximately 40% compared to control values. Liver cell plasma membranes enriched in canalicular fractions (BCM) and plasma membranes enriched in sinusoidal and lateral fractions (PM), microsomes, mitochondria and cytosol were isolated by differential centrifugation. Total lipids were extracted and measured colorimetrically. To assess fluidity, membranes were incubated in vitro with fluorescent probes [1,6-diphenyl-1,3,5-hexatriene and 1-(4'-trimethyl-ammonium-phenyl)-6-phenyl-1,3,5-hexatriene]. After Mn-BR treatment, BCM cholesterol incorporation increased markedly (about 3-fold) accompanied by a decrease in fluidity. BCM phospholipid content was unaltered by the cholestatic challenge. In PM-enriched fractions, the changes in cholesterol and phospholipid content after Mn-BR treatment were not statistically significant ( P > 0.05) compared to controls. Furthermore, the biochemical alterations in PM were not accompanied by changes in membrane fluidity. These results support the hypothesis that altered lipid composition and fluidity of BCM are involved in the pathogenesis of Mn-BR cholestasis. 相似文献
138.
Polymorphonuclear leukocytes (PMNs) adhere to endothelial cells at sites of acute inflammation. To examine this phenomenon in vitro, we have developed a new assay to measure adherence of PMNs to cultured endothelial cells. Human PMNs were labeled with 111indium-oxine and incubated in microtiter wells with monolayers of either human umbilical vein or bovine aortic endothelial cells. Following incubation, the wells were sealed, inverted, and centrifuged at varying speeds. Results are expressed as the percentage of PMNs added initially that remained attached to the monolayers after being subjected to dislodgment forces (ie, relative centrifugal forces) ranging from 1 to 1,200 g. Adherence of PMNs to endothelial monolayers was temperature dependent, dependent on the concentration of extracellular Mg2+ (but not Ca2+), and enhanced significantly by the chemotactic peptides, N-formyl-methionyl-leucyl- phenylalanine (fMLP) and human C5a. It was found that fMLP and C5a not only increased the number of PMNs that adhered to endothelial cells, but also increased the strength of adherence. 相似文献
139.
T Kullmann I Barta Z Lázár B Szili E Barát M Valyon M Kollai I Horváth 《The European respiratory journal》2007,29(3):496-501
Exhaled breath condensate (EBC) pH is considered to reflect the acid-base balance of the airways. Current pH measurements do not take into account the effect of CO2. The aim of the present study was to determine the effect of condensate CO2 partial pressure on pH and to provide a more precise mode of EBC pH determination. Condensate pH and CO2 partial pressure were measured in parallel from 12 healthy volunteers and 12 asthmatics using a blood gas analyser in neat, argon de-aerated and CO2-loaded samples. The regression analysis was used to test the relationship between pH and CO2, and to calculate the pH at a CO2 level of 5.33 kPa (physiological alveolar CO2 partial pressure). Reproducibility of different pH readings was compared using the Bland-Altman test. Condensate CO2 concentration was variable both in neat and argon de-aerated samples. There was a close negative logarithmic relationship between CO2 and pH. Calculation of pH at a CO2 level of 5.33 kPa provided reproducibility approximately six times as good as that of the currently used measurements. Condensate CO2 partial pressure influences pH measurements. Determination of pH at a standard CO2 level provides the most reproducible condensate pH values to date. 相似文献
140.
Lupus anticoagulants are spontaneously occurring antibodies with specificity for negatively charged phospholipids. The plasma of a patient with such a polyclonal antibody of IgM type demonstrated low levels of factor VIII coagulant activity (VIII:C) and factors IX, XI and XII when analyzed by biologic clotting assays, whereas in immunochemical assays, normal levels of VIII coagulant antigen and factor IX were obtained. After immunoadsorption of patient plasma with anti-IgM Sepharose, normal biologic activities were demonstrated in clotting assays for VIII:C, factors IX, XI, and XII. The addition of the patient's isolated IgM to normal plasma resulted in grossly abnormal results in these coagulation assays, and a pattern similar to that of the patient's plasma was obtained. The inhibitory effect of the patient's lupus anticoagulant on blood coagulation was demonstrated also in platelet-rich plasma. The results of the clotting assays indicated that the anticoagulant inhibited several of the reactions in the blood coagulation cascade. The availability of purified components made it possible to demonstrate an inhibiting effect on the activation of prothrombin by factor Xa in the presence of isolated platelets, as well as in a system where purified factor V and well defined phospholipid vesicles were substituted for the platelets. 相似文献