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991.
Multiphase radon generation and transport in porous materials   总被引:5,自引:0,他引:5  
Radon generation and transport in porous materials involve solid, liquid, and gas phases in the processes of emanation, diffusion, advection, absorption, and adsorption. Oversimplifications, such as representing moist soil systems by air-phase emanation and transport models, cause theoretical inconsistencies and biases in resulting calculations. Detailed Rn rate balance equations for solid, liquid, and gas phases were analyzed and combined using phase equilibrium constants to derive a single diffusive-advective rate balance equation in the traditional form. The emanation, diffusion, and permeability coefficients in the new equation have expanded definitions and interpretations to include Rn phase transfer. Radon adsorption was characterized by an exponential moisture dependence, and diffusion and permeability constants utilized previous moisture relationships. Correct boundary and interface conditions were defined, and the unified theoretical approach was applied to field data from a diffusion-dominated system and to laboratory data from an advection-dominated system. Measured 222Rn fluxes and concentrations validated the modeled values within the measurement variability in both applications.  相似文献   
992.
Thirteen patients with a malignant germ cell tumor of the ovary have been treated with a combination of vinblastine, bleomycin, and cisplatin (VBP). In 12 patients a complete remission was reached, which was maintained in 10 of these patients. One patient with large tumor residues and a partial remission became CR after surgery. The tumor recurred in 2 patients after 6 and 27 months. Overall, 11 of these patients are in long-term remission, from 14 to 84 months after the start of treatment. VBP is an effective treatment for malignant germ cell tumors of the ovary, even in patients with large tumor residuals.  相似文献   
993.
994.
There is limited information regarding oral health status and other predictors of oral health‐related quality of life. An association between oral health status and perceived oral health‐related quality of life (OHQOL) might help clinicians motivate patients to prevent oral diseases and improve the outcome of some dental public health programs. This study evaluated the relationship between older persons' OHQOL and their functional dentition, caries, periodontal status, chronic diseases, and some demographic characteristics. A group of 733 low‐income elders (mean age 72.7 ISD=4.71, 55.6% women, 55.1% members of ethnic minority groups in the U.S. and Canada) enrolled in the TEETH clinical trial were interviewed and examined as part of their fifth annual visit for the trial. OHQOL was measured by the Geriatric Oral Health Assessment Index (GOHAI); oral health and occlusal status by clinical exams and the Eichner Index; and demographics via interviews. Elders who completed the four‐year assessment had an average of 21.5 teeth (SD=6.9). with 8.5 occluding pairs (SD=4.6), and 32% with occlusal contacts in all four occluding zones. Stepwise multiple regressions were conducted to predict total GOHAI and its subscores (Physical, Social, and Worry). Functional dentition was a less significant predictor than ethnicity and being foreign‐bom. These variables, together with gender, years since immigrating, number of carious roots, and periodontal status, could predict 32% of the variance in total GOHAI, 24% in Physical, 27% in Social, and 21 % in the Worry subscales. These findings suggest that functional dentition and caries influence older adults' OHQOL, but that ethnicity and immigrant status play a larger role.  相似文献   
995.
BACKGROUND: Adjustable gastric banding is a popular bariatric operation in Europe. About 1500 patients per year undergo a such procedures in Germany. Clinical data on the rate of long-term complications such as pouch dilatation, slippage, and band migration are available in only a few long-term studies with small numbers of patients. Meta-analyses report on comordities and reduction in weight. The rate and management of long-term complications were examined at this inquiry. METHODS: Ninety hospitals were asked about rates of band implantation, follow-up, and complications. Thirty-eight hospitals (42.2%) participated in the study. The management of complications including slippage, pouch dilatation, and band migration was analyzed. RESULTS: At 35 hospitals, 4138 patients underwent gastric banding procedures in 25 hospitals over more than 5 years. The mean follow-up rate is presently 85.3%. Long-term complications were described in 8.6% of the patients. Pouch dilatation occurred in 5.0%, slippage in 2.6%, and band migration in 1.0%. CONCLUSIONS: Laparoscopic adjustable gastric banding can effectively achieve weight loss. However, band-related and functional complications influence late outcome. The rate of long-term complications was equivalent to that already in the literature.  相似文献   
996.
OBJECTIVE: To estimate the gestational age ranges that result in optimal birth outcomes for each of four risk-defined groups. STUDY DESIGN: Retrospective cohort study of singleton late third-trimester deliveries at a large urban teaching hospital between July 1995 and September 2003. Low-risk, advanced maternal age, hypertensive and diabetic patients were identified and grouped. Rates, by day of gestation at delivery, of cesarean delivery, major maternal perineal trauma, low 5-min APGAR score and NICU admission were determined for each study group. RESULTS: Each study group had meaningful changes in rates of obstetric outcomes as a function of gestational age at delivery and these patterns differed from group to group. A unique optimal time of delivery (OTD) was estimated for each group. The low-risk group OTD was calculated to be 37 weeks 1 day to 41 weeks 0 day; the advanced maternal age group OTD was 38 weeks 5 days to 39 weeks 6 days; the hypertension group OTD was 39 weeks 2 days to 40 weeks 1 day; and the diabetes mellitus group OTD was 40 weeks 3 days to 41 weeks 1 day. CONCLUSIONS: The OTD varied based on obstetrical risk. Strategies to increase the proportion of deliveries that occur within the OTD for specific risk-defined groups could theoretically improve birth outcomes.  相似文献   
997.
Introduction     
Raymond C. Read 《Hernia》2006,10(6):454-455
  相似文献   
998.
999.
The risks of viral transmission from trauma patients is a continuing concern to those involved in their care. However, the prevalence of hepatitis (HPT) in trauma patients is poorly described. The purpose of this study is to evaluate the prevalence of HPT in trauma patients admitted to an urban trauma center. Two hundred sixty-four consecutive admissions to an urban Level I trauma center underwent serologic screening for HPT. Risk factors were assessed by direct patient questioning. Serologic evidence of HPT B was found in 19.7 per cent of patients. Intravenous (IV) drug abusers represented eight per cent of the study population; this group had a 67 per cent rate of seropositivity. Hepatitis A was not found in any patient. Antigenemia was found in 1.9 per cent of patients. It is concluded that HPT B seropositivity is common in trauma patients. IV drug abusers have particularly high prevalence of HPT. This high prevalence rate of HPT B serology poses a significant risk to those involved with the care of trauma patients. The authors suggest that specific protocols to avoid the transmission of viral disease should be mandatory in urban trauma centers.  相似文献   
1000.
New long-acting beta 2-adrenoceptor agonists, formoterol and salmeterol, may soon appear in several European countries for treatment of asthma. This review examines currently available information and compares the basic pharmacology and describes the clinical effects of these new drugs. The long duration of bronchodilation seen in clinical studies seems to be similar, whereas in isolated tissues there might be a difference in the binding characteristics to the beta 2-adrenoceptor. Long-acting beta 2-agonists could have an inhibitory effect on inflammatory events related to asthma, but the clinical relevance of these effects is not clear at present. Long-term studies up to one year with both new drugs have not shown any unexpected side-effects, and no tachyphylaxis to beta-adrenoceptor stimulation has been reported. Patients appear to strongly prefer the new drugs compared to the short-acting beta 2-agonists. The potential place for these drugs in the treatment of asthma is discussed and some pitfalls pointed out. It is likely that the long-acting beta 2-agonists will be beneficial to many asthmatic patients.  相似文献   
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