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81.
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   
82.
We describe a case of cholangiocarcinoma in a young woman, who presented with cholestatic jaundice following oral contraceptive ingestion. Following diagnostic laparotomy she received intra-arterial 'lipiodolized' chemotherapy. Intravenous mitozantrone was given for 2 years and she is asymptomatic, with computed tomographic evidence of tumour response, 27 months after diagnosis. We suggest that this form of treatment is of value for cholangiocarcinoma.  相似文献   
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84.
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   
85.
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   
86.
87.
BACKGROUND: Mortality due to cryptogenic fibrosing alveolitis (CFA) is increasing, particularly in the elderly. Optimum management remains uncertain and previous studies of the disease have largely been from specialist centres. A national study was carried out of the presentation and initial management of CFA in the UK. METHODS: All respiratory physicians in England, Scotland and Wales were invited to enter patients with newly diagnosed CFA over a two year period. CFA was diagnosed on histological grounds or according to clinical criteria which included the absence of a defined connective tissue disorder or pneumoconiosis. Participating physicians (n = 150) completed a questionnaire at patient entry and at all subsequent follow up visits and death. RESULTS: A total of 588 patients (373 men, 63%) were studied of whom 441 (75%) were referrals from primary care. Their mean (SD) age was 67.4 (10.0) years and median duration of symptoms at presentation was 9.0 months. Clubbing was more common in men (203/373; 54%) than in women (86/ 215; 40%); 209 patients (36%) were graded as severely breathless at presentation. A history of dust exposure (organic or inorganic) was present in 274 patients (47%) of whom 87 had had some exposure to asbestos. Subjects exposed to dust were more likely to have smoked and had slightly higher mean lung volumes, but were otherwise indistinguishable from those not exposed in terms of clinical presentation, management, and outcome. Transbronchial biopsy specimens were taken in 164 patients (28%) and open lung biopsy specimens in 73 (12%), but 60% had no histological diagnostic procedure. Biopsy procedures were more likely to be performed in younger patients, those with better lung function, and those with a history of asbestos exposure. At presentation a decision not to initiate specific treatment was made in 284 cases (48%). The decision to initiate treatment was made predominantly on symptomatic grounds. Two years after the close of entry to the study 266 patients (45%) had died. CONCLUSIONS: CFA is predominantly a disease of elderly patients and has a poor prognosis. Physicians generally considered CFA to be a clinical diagnosis and did not initiate treatment in up to half of patients at presentation.


  相似文献   
88.
We studied nine patients with a subacute onset of a pancerebellar syndrome. Six had known cancer (three small-cell carcinoma of the lung [SCLC], one metastatic small-cell carcinoma, one small-cell carcinoma of the prostate, and one non-Hodgkin's lymphoma). Six of eight who had neurophysiologic testing, including the three patients without detectable cancer, had coexistent Lambert-Eaton myasthenic syndrome (LEMS). In two of the patients, LEMS was discovered only by neurophysiologic testing. We looked for anti-Purkinje cell autoantibodies in all patient's sera and in four patients' CSF. We also looked for autoantibodies to voltage-gated calcium channels (VGCCs) in seven patients' sera and two patients' CSF, using the 125I-omega-conotoxin radioimmunoassay. We were unable to detect anti-Purkinje cell autoantibodies in any patients' serum or CSF. However, there were raised titers of anti-VGCC autoantibodies in five of seven patients' serum, including one patient with SCLC who did not have LEMS, and in the CSF of one of two patients. We conclude that the frequency of presentation of a pancerebellar syndrome with LEMS is higher than expected by chance and is usually associated with cancer. In some of these patients, LEMS may be clinically occult. The presence of LEMS and raised titers of anti-VGCC autoantibodies in some patients with subacute cerebellar degeneration is suggestive of an autoimmune etiology even though anti-Purkinje cell antibodies could not be detected. Anti-VGCC autoantibodies are not confined to LEMS. They may be found at high titer in CSF as well as serum.  相似文献   
89.
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   
90.
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   
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