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排序方式: 共有715条查询结果,搜索用时 109 毫秒
51.
E Thorsen K Segadal E Myrseth A P?sche A Gulsvik 《Occupational and environmental medicine》1990,47(4):242-247
To assess the effects of deep saturation dives on pulmonary function, static and dynamic lung volumes, transfer factor for carbon monoxide (T1CO), delta-N2, and closing volume (CV) were measured before and after eight saturation dives to pressures of 3.1-4.6 MPa. The atmospheres were helium-oxygen mixtures with partial pressures of oxygen of 40-60 kPa. The durations of the dives were 14-30 days. Mean rate of decompression was 10.5-13.5 kPa/hour. A total of 43 divers were examined, six of whom took part in two dives, the others in one only. Dynamic lung volumes did not change significantly but total lung capacity (TLC) increased significantly by 4.3% and residual volume (RV) by 14.8% (p less than 0.05). CV was increased by 16.7% (p less than 0.01). The T1CO was reduced from 13.0 +/- 1.6 to 11.8 +/- 1.7 mmol/min/kPa (p less than 0.01) when corrected to a haemoglobin concentration of 146 g/l. Effective alveolar volume was unchanged. The increase in TLC and decrease in T1CO were correlated (r = -0.574, p less than 0.02). A control examination of 38 of the divers four to six weeks after the dives showed a partial normalisation of the changes. The increase in TLC, RV, and CV, and the decrease in T1CO, could be explained by a loss of pulmonary elastic tissue caused by inflammatory reactions induced by oxygen toxicity or venous gas emboli. 相似文献
52.
53.
M K Thorsen S J Erickson M W Mewissen J E Youker 《Journal of computer assisted tomography》1990,14(6):1007-1009
Partial anomalous pulmonary venous return to the azygos vein is very unusual, occurring in 0.02% of autopsy examinations. We report the CT, magnetic resonance, and angiographic findings in a 67-year-old man with partial anomalous venous return to the azygos vein. 相似文献
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56.
Increased gut permeability following burn trauma 总被引:1,自引:0,他引:1
M D Epstein J I Tchervenkov J W Alexander J R Johnson J W Vester 《Archives of surgery (Chicago, Ill. : 1960)》1991,126(2):198-200
Twenty female Hartley guinea pigs, weighing 350 to 400 g, were given a 30% full-thickness burn injury. Gastrointestinal permeability was assessed before burn and on postburn days 1 through 3, 7, and 14 by administering 5 mL of an isotonic mixture of 8% lactulose and 1.15% L-rhamnose by gavage and measuring the urinary excretion for the next 7 hours. In normal guinea pigs, lactulose (molecular weight, 342d) is mostly absorbed by the paracellular route, whereas L-rhamnose (molecular weight, 164 d) is mostly absorbed by the transcellular route. Gut permeability to L-rhamnose did not increase after burn injury (211 micrograms before burn vs 230, 260, 180, 238, and 221 micrograms on days 1, 2, 3, 7, and 14, respectively, after burn). By contrast, gut permeability to lactulose increased significantly and was greatest in the first 48 hours after burn injury (60 micrograms before burn vs 380, 354, 203, 364, and 279 micrograms on days 1, 2, 3, 7, and 14, respectively, after burn). Gut permeability to low-molecular-weight compounds increases immediately after burn trauma, and this may be by a paracellular rather than transcellular mechanism. 相似文献
57.
Binding of 125I-labelled fibrin(ogen) fragments to platelets and to immunoprecipitated glycoprotein IIb-IIIa complex 总被引:1,自引:0,他引:1
To further investigate which parts of the fibrinogen molecule that are responsible for its binding to the fibrinogen receptor on human platelets, the following approaches were made: The glycoprotein IIb-IIIa complex (the putative fibrinogen receptor) was immunoprecipitated in crossed immunoelectrophoresis of Triton X-100-extracts of platelets against antibodies to whole platelet proteins. Subsequently, the immunoplates were incubated with 125I-labelled, plasmin- or CNBr-cleaved fibrinogen fragments (pre-X,X,Y,D,Degta,Efg,N-DSK) or fibrin fragments (E1,N-dsk), characterized by partial sequenation. The immunoplates were exposed to X-ray films, and binding of the fragments to the glycoprotein IIb-IIIa complex was examined. The findings were compared to the results obtained from studies on binding of the same fragments to intact gel-filtered platelets after ADP-stimulation. The following conclusions were made: All fragments except Efg and Degta bound to the immunoprecipitated GPIIb-IIIa complex as well as to ADP-stimulated platelets suggesting that at least two sequences in the E domain and one in each of the D domains of fibrinogen are involved in binding to the platelet receptor. The GPIIb-IIIa complex is the only surface-located platelet antigen that binds fibrinogen and the aforementioned fragments. The binding of the fragments to the receptor is dependent on divalent cations. 相似文献
58.
Hematuria in childhood is observed in up to 2 %. The underlying diseases are quite different from adult patients. Hereditary disorders, glomerulonephritis or infections are frequent causes, malignancies are rare. Except from isolated microhematuria a thorough diagnostic evaluation is mandatory to ensure early effective treatment. 相似文献
59.
Detection of pleural effusions on supine chest radiographs 总被引:1,自引:0,他引:1
J A Ruskin J W Gurney M K Thorsen L R Goodman 《AJR. American journal of roentgenology》1987,148(4):681-683
A prospective analysis of anteroposterior supine radiographs in 34 patients was undertaken to determine the detectability of pleural effusions on supine radiographs. The presence of pleural effusions and quantity of fluid (small, moderate, or large) were evaluated by using the following radiographic signs: increased homogeneous density superimposed over the lung, loss of the hemidiaphragm silhouette, blunted costophrenic angle, apical capping, elevation of the hemidiaphragm, decreased visibility of lower-lobe vasculature, and accentuation of the minor fissure. Decubitus radiographs were performed to identify and to estimate the quantity of pleural fluid. Sixty-two hemithoraces were evaluated by three observers. From a total of 36 pleural effusions shown on decubitus views, 24 were correctly identified on supine radiographs (sensitivity of 67%, specificity of 70%, and accuracy of 67%). The most frequent but least specific criterion for detecting pleural effusions on supine radiographs is blunting of the costophrenic angle. Other helpful signs include loss of the hemidiaphragm and increased density of the hemithorax. A normal supine radiograph does not exclude a pleural effusion. Our results show that supine radiographs are only moderately sensitive and specific for the evaluation of pleural effusions. 相似文献
60.
Kirkham SR Smye V Tang S Anderson J Blue C Browne A Coles R Dyck I Henderson A Lynam MJ Perry J Semeniuk P Shapera L 《Research in nursing & health》2002,25(3):222-232
The concept of culture has been widely applied as an explanatory concept within health care, often within a framework representing culture as a fixed, reified entity, with cultural groups existing in a binary sense vis-;-vis mainstream culture. However, if our scholarship is to generate knowledge that addresses longstanding patterns of inclusion and exclusion along lines such as race, ethnicity, class, and gender, interpretive frames are needed that account for culture as embedded in fields of power relations; as mediated by social forces such as economics, politics, and historical patterns of oppression and colonization; and as being constantly renegotiated. In this article we trace a series of theoretical explorations, centered on the concept of cultural safety, with corresponding methodological implications, engaged in during preparation for an intensive period of fieldwork to study the hospitalization and help-seeking experiences of diverse ethnocultural populations. 相似文献