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71.
72.
A questionnaire was given to representative samples of Norwegian recruits in 1990 and 1999 to explore dental health habits, history of gastroesophageal disorders and diet with possible relations to dental erosion. The samples were 792 (mean age 20.9 years) and 676 (mean age 21.6 years), respectively, and the corresponding responses were 62% and 100%. Minor differences in self-reported dental health habits and gastroesophageal disorders were found. The respondents' dentists had provided information about dental erosion for 8.2% of the respondents in 1990 versus 14.5% in 1999. There was an increase in the reported frequency of daily intake of juice from 17% to 24% (P = 0.006) and carbonated soft drink from 54% to 61% (P = 0.025) in the period 1990-99. The frequency of training activity showed minor changes, but in 1999 it was more common to drink during exercise (94% versus 74% in 1990, P < 0.001), and the majority drank water. Sixteen percent of recruits ate oranges daily in 1990; in 1999 this had dropped to 11% (P = 0.012). The corresponding proportion that ate apples daily had dropped from 17% to 8% in the period (P < 0.001). It is likely that lifestyle factors related to diet among young men have changed in the period 1990-99 in a direction that may increase the prevalence of dental erosions.  相似文献   
73.
BACKGROUND: To compare irinotecan with the Nordic 5-fluorouracil (5-FU) and folinic acid (FA) bolus schedule [irinotecan 180 mg/m(2) on day 1, 5-FU 500 mg/m(2) and FA 60 mg/m(2) on day 1 and 2 (FLIRI)] or the Lv5FU2 schedule [irinotecan 180 mg/m(2) on day 1, FA 200 mg/m(2), 5-FU bolus 400 mg/m(2) and infused 5-FU 600 mg/m(2) on day 1 and 2 (Lv5FU2-IRI)] due to uncertainties about how to administrate 5-FU with irinotecan. PATIENTS AND METHODS: Patients (n = 567) with metastatic colorectal cancer were randomly assigned to receive FLIRI or Lv5FU2-IRI. Primary end point was progression-free survival (PFS). RESULTS: Patient characteristics were well balanced. PFS did not differ between groups (median 9 months, P = 0.22). Overall survival (OS) was also similar (median 19 months, P = 0.9). Fewer objective responses were seen in the FLIRI group (35% versus 49%, P = 0.001) but the metastatic resection rate did not differ (4% versus 6%, P = 0.3). Grade 3/4 neutropenia (11% versus 5%, P = 0.01) and grade 2 alopecia (18% versus 9%, P = 0.002) were more common in the FLIRI group. The 60-day mortality was 2.4% versus 2.1%. CONCLUSIONS: Irinotecan with the bolus Nordic schedule (FLIRI) is a convenient treatment with PFS and OS comparable to irinotecan with the Lv5FU2 schedule. Neutropenia and alopecia are more prevalent, but both regimens are equally well tolerated.  相似文献   
74.
In a county hospital serving a population of roughly 240,000, the hospital records from the period 1982 to 1987 included 27 patients who presented with traumatic rupture of the thoracic aorta. Eighteen patients died instantaneously, one was dead on admission, five died in hospital and three survived operation. Two patients had direct cross clamping of the aorta and Dacron interposition graft soon after admission; both survived. The third patient had a Gott shunt and Dacron interposition graft the day after the accident and survived with paraplegia. In all patients who died in hospital except one, the condition was not diagnosed before death. We conclude that traumatic rupture of the thoracic aorta occurs more frequently than is generally thought. Although most patients die at the scene of the accident, a liberal use of angiography is indicated in all trauma cases admitted to hospital with a history of a forceful deceleration or acceleration injury.  相似文献   
75.
This study aimed to asses the effect of silicate cement on Copalite -covered cavity walls in extracted human teeth. Class V cavities were prepared in 24 premolars and filled with silicate cement (Bio-Trey). Four cavities were unlined, the rest of the cavities were lined with 1 or 2 layers of Copalite before insertion of the restorations. After 6 months, 70-100 microns thick longitudinal sections of the teeth were studied by polarized light microscopy, microradiography and electron probe microanalysis. When imbibed in water or quinoline, a subsurface zone of altered birefringence was noticed in nearly all cavity walls. Nearly half of the cavity walls in the experimental groups showed a surface zone of increased radiopacity. In a few instances a subsurface radiolucent zone was present. By electron probe microanalysis F (0,4-3% by weight), Zn (1-4%) and Al (0,2-6%) were measured in the outer 10-60 microns of the cavity walls. The study shows that even with a double layer of Copalite, known to prevent microleakage, a desirable uptake of F and Al from silicate restorations into cavity walls can take place. Copalite does not prevent a phosphoric acid effect on the cavity walls.  相似文献   
76.
A human melanoma cell line with unusually high growth potential was established from a xenograft growing in athymic mice. When xenograft fragments were cultured in vitro, melanoma cells grew out rapidly without any contamination of mouse stromal cells. An established cell line, FME, derived from this tumour, grew both in monolayer and in shaker suspension culture with doubling times of about 20 h. The cells grew easily at low serum concentrations and could even be cultured in serum-free medium supplemented with insulin and transferrin. The cultured cells were hyperdiploid, as were the cells of the xenograft. The cells grew easily in soft agar and formed tumours in athymic mice. When growing exponentially, the cells were almost unpigmented, but when grown to high density, their melanin content increased. Upon treatment with dimethyl sulphoxide (DMSO), retinoic acid and theophylline, as well as with the tumour promoter 12-O-tetradecanoyl phorbol-13-acetate (TPA), the cells showed growth inhibition and increased melanin synthesis.  相似文献   
77.
Seven teeth which showed radiopaque zones beneath silicate fillings were sectioned and studied by microradiography and electron microprobe analysis in order to elucidate which elements were responsible for the increased absorption of X-rays and whether the presence of carious lesions could be masked by foreign elements in the tissue. The Ca concentration was frequently found to be either slightly increased or reduced compared with radiographically unaltered dentin. Increased concentrations of F and Zn occurred in the radiopaque zones. The highest F concentrations (0.4--1%) were recorded in zones with an increased Ca content. The highest Zn concentrations (5--8%) were found in the three specimens having a reduced Ca content. The possible conditions responsible for the increased Ca, F and Zn concentrations are discussed. The results indicate that both Ca and Zn may contribute to the increased absorption of X-rays. The hypothesis that carious dentin may be obscured in intraoral radiographs by the presence of foreign elements in the tissue, was not substantiated.  相似文献   
78.
79.
BACKGROUND: Risk factors for pulmonary embolism (PE) have been identified in the general population but have not been studied in a national population of renal transplant recipients. METHODS: Therefore, 33,479 renal transplant recipients in the United States Renal Data System from 1 July 1994-30 June 1997 were analyzed in a historical cohort study of hospitalized PE (ICD9 Code 415.1x). HCFA form 2728 was used for comorbidities. RESULTS: Renal transplant recipients had an incidence of PE of 2.26 hospitalizations per 1000 patient years at risk. In multivariate analysis, polycystic kidney disease (adjusted odds ratio, 4.44, 95% confidence interval, 2.31-8.53), older recipient age, higher recipient weight, cadaveric donation, history of ischemic heart disease, and decreased serum albumin were associated with increased risk of PE. Body mass index and hemoglobin were not significant. Kidney-pancreas transplantation was also not significant. In Cox Regression analysis PE was associated with increased mortality (hazard ratio 2.06, 95% CI 1.34-3.18). CONCLUSIONS: The most important risk factors for PE in this population were polycystic kidney disease, advanced age and increased weight. The reasons for the increased risk of polycystic kidney disease remain to be determined but were independent of hematocrit level at initiation of end stage renal disease, and may result from venous compression. Prospective studies of anatomical and hemostatic changes after renal transplantation in recipients with polycystic kidney disease are warranted.  相似文献   
80.
AIMS: Hospitalized fungal infections are reported frequently in renal transplant recipients and peritoneal dialysis patients, but the frequency of hospitalized fungal infections in dialysis patients has not been studied in a national population. METHODS: 327,993 dialysis patients in the United States Renal Data System initiated from January 1, 1992 to June 30, 1997 were analyzed in a retrospective registry study of fungal infections (based on ICD9 Coding). RESULTS: Dialysis patients had an age-adjusted incidence ratio for fungal infections of 9.80 (95% confidence interval (CI) 6.34-15.25)) compared to the general population in 1996 (the National Hospital Discharge Survey). Candidiasis accounted for 79% of all fungal infections, followed by cryptococcosis (6.0%) and coccidioidomycosis (4.1%). In multivariate analysis, fungal infections were associated with earlier year of dialysis, diabetes, female gender, decreased weight and serum creatinine at initiation of dialysis, chronic obstructive lung disease and AIDS. In Cox regression analysis the hazard ratio for mortality of fungal infections was 1.35 (95% CI 1.28-1.42). CONCLUSIONS: Dialysis patients were at increased risk for fungal infections compared to the general population, which substantially decreased patient survival. Female and diabetic patients were at increased risk for fungal infections. Although candidiasis was the dominant etiology of fungal infections, the frequency of cryptococcosis and coccidioidomycosis were higher than previously reported.  相似文献   
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