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31.
A quantitative measure of the vascular permeability surface area product (PS) for albumin has been made using a double isotope technique. PS was significantly elevated in irradiated rat lung, heart, skin, and muscle, between 19 and 26 days following 18 or 25 Gray thorax irradiation. Administration of dexamethasone from 2 days before irradiation through the day of measurement suppressed the expected increase in PS in lung, heart, and muscle, but not in skin. Shorter periods of steroid administration were not as effective in suppressing this response to radiation exposure. Increased vascular permeability following radiation may be an essential element in the development of radiation fibrosis. We hypothesize that the ability to suppress this response could result in a long term reduction in the incidence of fibrosis.  相似文献   
32.
PURPOSE: In this study, we examined the use of a 2.0-mm locking bone plate/screw system in mandibular surgery. PATIENTS AND METHODS: All patients who were treated with a 2.0-mm locking bone plate/screw system during an 8-month period for fractures of the mandible or other defects of the mandible were prospectively studied. Ease of use of locking plate/screw system, characteristics of the fractures and defects, and complications were tabulated. RESULTS: A total of 80 fractures in 59 patients were treated with the 2.0-mm locking plate/screw system. One hundred two 2.0-mm locking plates were applied to the 80 fractures; 58 fractures received 1 plate and 22 fractures received 2 plates. There were no intraoperative difficulties associated with their application. Fracture reductions were considered to be excellent in all cases. At the latest follow-up, all fractures had healed, but 2 patients had slight malocclusions. Six patients developed postsurgical infections. Only 1 patient required hospitalization for treatment of the infection; all others were managed in the outpatient clinic. Four patients required removal of their plates for varying reasons. CONCLUSIONS: The use of a 2.0-mm locking plate/screw system was found to be simple and to provide sound fixation in all cases.  相似文献   
33.
Obesity: A public health problem in Ireland?   总被引:1,自引:0,他引:1  
We examined the prevalence of different categories of body weight in a random sample of men and women aged 35 to 64 years studied in 1985 in County Kilkenny, Ireland. The largest group was those classified as overweight — 51.1% of men and 44.7 % of women. There were 13.7 % of men and 19.2% of women in the obese category. The obese were older but the distribution by social class did not differ significantly from the non-obese. Obese women had significantly more children born alive and a higher prevalence of positive angina questionnaire than those who were not obese. Serum total cholesterol was higher in obese men and HDL cholesterol was lower in obese men and obese women. Systolic and diastolic blood pressures were significantly higher in obese men and women but smoking status was similar. In a multiple logistic regression analysis, systolic blood pressure in men and diastolic in women remained significantly associated with obesity; there was an inverse association between obesity and HDL cholesterol in women and between obesity and HDL-cholesterol as a proportion of total cholesterol in men.  相似文献   
34.
During a three-year period, 95 adults were treated by lower-extremity amputations for peripheral vascular insufficiency. A multidisciplinary team for presurgical evaluation determined all to be potentially independent walkers with a prosthesis. Patients were graded for level of independent walking before amputation and again at a minimum two-year follow-up examination using a seven-level functional grading system. Seventy-six of 90 patients (84%) ambulated within one functional level of their preamputation status. This return to preamputation level of function was maintained whether comparing preamputation functional level or surgical amputation level. Prosthetic use increased and the use of walking aids decreased with increased functional ambulation levels, but did not correlate with surgical levels. Peripheral vascular insufficiency patients can maintain walking independence. Multidisciplinary presurgical evaluation helps selection of the amputation level and correct prosthetic limb fitting.  相似文献   
35.
BACKGROUND: We hypothesise that the density of proliferating cells at the invasive tumour front (ITF) has a positive relationship with prognostic and risk factors in human oral squamous cell carcinoma (SCC). METHODS: Tissues from 47 human oral SCC specimens were collected and stained with a monoclonal antibody directed against the Ki-67 antigen using a horseradish peroxidase based two-step immunostaining method. Counting was performed on two parallel sections at the ITF using an image analyser. The Ki-67 labelling index (LI) was determined by measuring the number of nuclei/mm(2) of epithelium. RESULTS: Our results show that the density of proliferating cells is related to clinical staging, with advanced stage of disease having a significantly higher Ki-67 LI compared with early stage of disease (2111 +/- 905 vs. 1908 +/- 913; P = 0.03). Importantly, this study shows that tumours that have metastasised have a significantly higher Ki-67 LI than tumours where distant metastasis was not detected (3257 +/- 650 vs. 1966 +/- 881; P < 0.0001). CONCLUSIONS: Cell proliferation, as measured by the Ki-67 LI at the ITF, has a positive relationship with clinical staging, tumour thickness, smoking status of the patient and alcohol consumption. Further, we suggest that a multicenter study with a large cohort of patients is indicated to fully elucidate whether cell proliferation at the ITF is directly related to patient survival.  相似文献   
36.
37.
M Beardmore  G Shaper  M Graham 《The Practitioner》1989,233(1470):819-20, 823
Results of investigations in extraordinary patients should be dealt with cautiously; it is often prudent to repeat tests. Though the aims of treatment in such cases are often the same, differences in approach to the problem are illuminating.  相似文献   
38.
The health status of many people in developing countries is often dismal compared with the norms in industrialized countries. Increasingly, medical practitioners in the United States and other industrialized countries have become interested in global health issues, an interest that often takes the form of short-term international medical trips. We discuss several ethical issues associated with participation in such trips and use our experiences in developing the Children's Health International Medical Project of Seattle (CHIMPS) to outline and illustrate a set of 7 guiding principles for making these trips. CHIMPS is a resident-run, faculty-supported international medical program founded in 2002 by pediatric residents at the University of Washington in Seattle. Members of CHIMPS work with a rural community in El Salvador to support ongoing public health interventions there and provide sustainable medical care in collaboration with the community and a local nongovernmental organization. The 7 principles developed as a result of this work-mission, collaboration, education, service, teamwork, sustainability, and evaluation-can be used as a model for health practitioners as they develop or select international medical trips. The importance of partnering with the community and working within the existing medical and public health infrastructure is emphasized. Many of the challenges of doing international medical work can be overcome when efforts are guided by a few specific principles, such as those we have outlined.  相似文献   
39.
Diffuse intravascular coagulopathy (DIC) or consumptive coagulopathy is infrequently associated with aortic aneurysms. When the two coexist, they create a difficult clinical problem that requires optimal medical and surgical care. Two cases of coagulopathy associated with aortoiliac aneurysm are presented to exemplify the broad clinical picture that can be present. The definitive treatment of DIC is removal of the underlying cause. The following recommendations are made for the management of patients with aortic aneurysms and possible coagulopathy: preoperatively examine the patient for hematomas and ecchymoses; measure levels of fibrinogen, platelets and fibrin degradation products and the prothrombin and partial thromboplastin times; perform arteriography and check puncture sites for spontaneous bleeding afterwards; at aneurysm repair ensure meticulous hemostasis and compensate for excessive blood loss by high-speed autotransfusion.  相似文献   
40.
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