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71.
Cardiac injuries--a clinical and autopsy profile   总被引:3,自引:0,他引:3  
One hundred two patients sustaining cardiac injuries over a 4-year period were analysed to highlight the natural history of the cardiac injuries. There were 45 blunt, 36 stab, and 21 gunshot injuries. The injury involved the ventricle in 85, atrium in seven, pulmonary artery in five cases, and resulted in crush injury to the heart in the remaining five cases. Thirty-three patients (32.3%) died on the scene and 58 (56.9%) died during the transportation. Only 11 patients (10.8%) reached the hospital alive, and ten of these patients survived following thoracotomy and repair of the cardiac injury. The factors influencing the natural course of cardiac injury were analysed: 2.2% of patients with blunt cardiac trauma reached the hospital alive compared to 19.4% with stab and 14.3% with gunshot injuries; ventricular injuries had a greater prehospital mortality compared to atrial or pulmonary artery injuries; 11.3% of patients sustaining injury to right ventricle reached the hospital alive compared to 3% of those with left ventricular injuries. These data emphasize the need for rapid transport, immediate recognition, and aggressive surgical management, to make a favourable impact on the natural history of cardiac injuries.  相似文献   
72.
In 12 children colostomy wound closure was undertaken with liberal extraperitoneal mobilisation of the bowel. In all the cases adequate length of the colonic loops could be achieved for resection of the colostomy and end to end anastomosis. There was only minor wound infection in 3 cases. There was no faecal fistula nor any postoperative intestinal obstruction.  相似文献   
73.
The external carotid artery (ECA) is an underestimated but important collateral to the cerebral hemisphere and eye in patients with severe disease of the internal carotid artery. Fifteen symptomatic patients with total occlusion of the internal carotid artery underwent ECA reconstruction. Ipsilateral ECA reconstruction was performed upon all patients with no mortality or neurologic deficits. Contralateral disease of the carotid artery was noted in 11 and required correction in seven patients. Follow-up study of the patients ranged from one to 68 months (a mean of 26.8 months) after operation. Vertebrobasilar symptoms persisted in two patients, both with contralateral disease. One of these patients successfully underwent extracranial-intracranial bypass. One ipsilateral and one contralateral stroke occurred during follow-up study, both in patients with contralateral disease. Eleven patients were alive and asymptomatic at last follow-up examination. Symptomatic selected patients with occlusion of the internal carotid artery and ECA stenosis or cul-de-sac formation should be considered for operation. ECA reconstruction is associated with little morbidity and three-fourths of the patients remain asymptomatic. A high incidence of contralateral disease of the carotid artery is present. Extracranial-intracranial bypass should only be considered when symptoms persist after correction of contralateral disease of the carotid artery and any ECA lesions.  相似文献   
74.
75.
This study utilizes parallel, longitudinal entomological and parasitological data collected during a 5-year vector control programme in Pondicherry, South India, to quantify Wuchereria bancrofti transmission from the vector to the human population. A simple mathematical model, derived from the standard catalytic model, is used to examine the hypothesis that current infection prevalence in young children is a dynamical function of their cumulative past exposure to infective bites. Maximum likelihood fits of the model to the observed data indicate a constant child infection rate with age, above a threshold representing the pre-patent period, or equivalently, the cumulative biting intensity required to produce patent infections. Extrapolation of the model allows the crude estimation of the equilibrium microfilaria age-prevalence curve due to control. The results suggest that vector control alone may have little impact on the overall age-prevalence of infection even when sustained for long periods. These observations are discussed in terms of the likely impact of density dependent mechanisms, such as acquired immunity, on model predictions.  相似文献   
76.
77.
McLellan  GL; Scalapino  MC 《Radiology》1988,169(1):264-265
A modified technique for catheterization of the pulmonary artery was developed. It involves the passage of a tapered, movable-core, J-tipped guide wire across the right ventricle into the pulmonary artery followed by the advancement of a straightened Grollman pigtail catheter. The technique was successful in 34 of 34 pulmonary artery catheterizations. The method avoids prolonged catheter manipulation within the right ventricle. In addition, since the catheter does not cross the tricuspid valve until the guide wire has been advanced, the occasional complication of the pigtail "hooking" on a tricuspid valve leaflet or chordae tendineae during catheter withdrawal and manipulation is prevented.  相似文献   
78.
The introduction of a lower cost alternative to a film commonly used for megavoltage radiation therapy port films led to a comparison of two films (Kodak X-TL and X-OMAT G) in four metal screen cassette configurations. In addition to determination of H-D curves and point spread functions, images of humanoid phantom sections were obtained and evaluated for clinical "usefulness." The X-OMAT G film-screen combinations compared favorably with the X-TL film combinations with respect to the H-D Curves and point spread functions but there was a slight preference for X-TL film. There were no differences noted whether the film was used in the standard "ready pack" or naked in the cassettes.  相似文献   
79.
This study reviews the demographic, radiologic, and histologic characteristics of 13 cases of an important primary skeletal neoplasm, giant cell tumor of bone, occurring in an uncommon location, the scapula. that eight of 13 patients presented prior to 20 years of age contrasts significantly with the typical age distribution (between 20–40 years) encountered in giant cell tumors arising in long bones. As it does elsewhere in the skeleton, giant cell tumor of the scapula frequently demonstrates cystic and/or telangiectatic components on histologic examination. The radiologic appearances of giant cell tumor in the scapula and in more typical locations are similar and include: (1) well-defined (geographic) margins, occasionally with a delicate sclerotic rim, (2) prominent trabeculations, (3) expanded bone contour, (4) frequent extension to the subchondral plate, and (5) absence of internal mineralization. Tumor sites within the scapula included: coracoid process, acromion, and body (three cases each); glenoid (two cases); and superior and inferior angles (one case each).The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the Department of the Army, the Department of Defense, or the Uniformed Services University of the Health Sciences.  相似文献   
80.
Perforin-dependent killing of tumor cells by Vgamma1Vdelta1-bearing T-cells   总被引:1,自引:0,他引:1  
The T-cell subset expressing Vdelta2 paired primarily with Vgamma2 comprises a majority of gammadelta T-cells in human adult peripheral blood and expands significantly during a variety of infectious diseases. In contrast, the other subset of gammadelta T-cells that express Vdelta1 is rare among circulating T-cells and its function is poorly understood. Here, we show that a Vgamma1Vdelta1(+) T-cell line, 3-D, established from human peripheral blood by immortalization with Herpesvirus saimiri was able to specifically recognize tumor cells, such as K562 cells, and release cytotoxic granules containing perforin for target cell killing. Some tumor cells, including Daudi cells that are known to be susceptible to killing by Vdelta2(+) T-cells, were resistant to 3-D killing, implicating distinct pathways for tumor cell control by Vdelta1(+) and Vdelta2(+) T-cells. The 3-D T-cell receptor (TCR):CD3 complex reconstituted in TCR-deficient Jurkat cells was capable of transmitting signals, evidenced by activation of the interleukin 2 (IL-2) gene following ligation with anti-CD3 antibody, yet the TCR-reconstituted cells failed to produce IL-2 in response to the target cells. Thus, these results raise the possibility that some Vgamma1Vdelta1(+) T-cells could potentially be stimulated and lyse tumor cells via ligation of TCR/CD3-unassociated molecules.  相似文献   
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