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21.
A case-control study to evaluate the efficacy of lung cancer screening conducted by us showed that lung cancer screening may reduce the mortality of the disease up to 28%. Assuming this efficacy is unbiased, and that the screening rate is 51.6%, which was observed in the control group in the above study, the number of lung cancer deaths prevented by screening in the study period was calculated to be 47 for males and females combined. In the same study population, screen-detected lung cancer patients (N = 207) in the same study period were followed and the 7-year survival rate (46.9%) was compared to the 5-year survival rate (11.3%) obtained by the Osaka Cancer Registry, in which screen-detected lung cancer patients were only 1.8%. The number of lung cancer deaths prevented by screening, estimated by the difference in the above two survival rates, was 74 (95% confidence interval; 55–93). The number of lung cancer deaths prevented by screening estimated from the case-control study was significantly lower than that estimated from the survival analysis. This indicates that the efficacy of lung cancer screening estimated by the case-control study was within the range that could be explained by the actual long-term survivors among the screen-detected patients in the study population.  相似文献   
22.
ABSTRACT. On the basis of epidemiological data and medical costs for patients with neuroblastoma, we have calculated the cost of mass screening for neuroblastoma with high performance liquid chromatography (HPLC) compared to the cost when it is not performed. If the sensitivity of the mass screening is 80 % and 22 000 infants are screened annually the cost will be 27809000 yen ($191800). If mass screening is not performed, the cost will be 28 446 000 yen ($196 200). The difference in cost (637 000 yen or $4 400) is fairly small. If the sensitivity is 75 % and 16 500 infants are screened, the difference is also small (174000 yen or $1 200). Therefore, mass screening with the HPLC method will not be an undue financial burden. But re-screening at an older age will be done with less financially favorable results, considering that the sensitivity may not be as high as that of the first screening and that mothers are somewhat reluctant about re-screening. The balance of the cost of mass screening by qualitative methods may also be less favorable, since the detection rate is low.  相似文献   
23.
BACKGROUND: We examined the prevalence of and risk factors for nocturia in Kurashiki city and the surrounding area, a rural area in Japan. MATERIALS AND METHODS: We collected data on 6517 individuals (4568 men and 1949 women) who participated in a multiphasic health screening. We analyzed the relationships between nocturia assessed by a questionnaire (voiding twice or more during night) and other variables including age, hypertension, cardiovascular disease, cerebrovascular disease, chronic obstructive pulmonary disease, diabetes mellitus (DM), chronic renal failure, benign prostatic hyperplasia (BPH), smoking habit and alcohol intake. RESULTS: Overall, 1856 individuals (28.5%) answered that they arose to urinate at least twice during the night. This rate increased with age from 16.5% in individuals younger than 50 to 60.0% in those older than 69. Logistic regression analysis revealed that cohorts of subjects 50-59, 60-69, and 70 years old or over had, respectively, 1.75, 3.35, and 6.21 times the prevalence of nocturia of the 49 years or younger cohort. Hypertension (odds ratio [OR] 1.64) and DM (OR 1.70) were other independent positive risk factors for nocturia. On the other hand, current smokers who smoked 20 or more cigarettes per day were less likely to have nocturia than non-smokers (OR 0.72). In male individuals, BPH was another independent positive risk factor (OR 1.35). Gender was not associated with nocturia. CONCLUSIONS: Although population bias is an important limitation to this study, nocturia is associated with various factors suggesting that multiple approaches are needed to the treatment of patients with nocturia.  相似文献   
24.
25.
A simple standardized screening test (South Australian Motor Co-ordination Screening Test, SAM Test) was developed to screen for poor co-ordination in 5 year olds; This SAM Test, which can be used by teachers, nurses and doctors, has explicit pass/fail criteria and has classified correctly 90% of children. The McCarthy Motor Scales, which are time consuming and limited to use by psychologists, were used to categorize 60 poorly co-ordinated and 60 normal children. The 120 children thus selected were tested on 19 items covering gross and fine motor skills. Statistical analysis to determine which items best discriminated between the two groups found the following five gross motor items to be most effective: one leg balancing, hopping, heel-toe walking on line, jumping Over ribbon and dropping ball and catching.  相似文献   
26.
Testing feces for occult blood is widely recommended as a means of detecting subclinical colorectal tumors. Guaiac tests such as Hemoccult® are the most widely used, but chemical sensitivity is relatively low and the tests are affected by dietary peroxidases, the state of fecal hydration, and certain drugs. The newly devised HemoQuant® and immunologic techniques appear more sensitive and specific, but they require further evaluation before widespread clinical usage can be recommended.Occult blood screening has both merits and weaknesses. Testing does uncover subclinical colorectal cancer, often at a relatively early stage, but whether this actually improves the prognosis remains to be proven. Benign neoplastic polyps are also detected, although it is debatable whether this is a valid rationale for screening. Test sensitivity for malignancy varies from good to moderate, but is poor for benign polyps. Specificity is usually around 97%–98%, yet the predictive value of a positive test for cancer is only about 10%: hence most test-positive individuals are needlessly subjected to invasive colonic investigations. Reported figures on public compliance with occult blood testing vary widely from excellent to poor. Published costs of screening are usually quite low, but these overlook important indirect and hidden expenses and are therefore misleading.On balance, the problems of occult blood testing currently appear to outweight the merits. This could change, however, with the newer testing techniques and with awaited mortality data from controlled clinical trials now underway.  相似文献   
27.
葡萄糖筛选试验在妊娠期糖尿病诊断及治疗中的价值   总被引:5,自引:1,他引:4  
目的 探讨 5 0 g葡萄糖筛选试验 (GCT)在妊娠期糖尿病 (GDM )诊断及治疗中的价值。 方法 选择 2 0 0 0年 1月~ 2 0 0 3年 6月在我院行产前检查并分娩的 5 0 gGCT异常的孕妇 36 8例 ,按血糖值分为 5组 :≥7.8~ <8.0mmol/L为Ⅰ组 ,≥ 8.0~ <9.0mmol/L为Ⅱ组 ,≥ 9.0~ <10 .0mmol/L为Ⅲ组 ,≥ 10 .0~ <11.0mmol/L为Ⅳ组 ,≥ 11.0mmol/L为Ⅴ组。比较 5组 75 g口服葡萄糖耐量试验 (OGTT)异常的比例及需用胰岛素治疗的病例数的差异。结果  5组GDM的发生率分别为 6 .9%、8.5 %、2 1.3%、4 7.8%和 85 .0 % ,75 gOGTT异常的发生率分别为 19.0 %、2 4 .2 %、5 1.1%、87.0 %和 90 .0 % ,且用胰岛素治疗的病例数随 5 0 gGCT血糖值的上升而增加。结论  5 0 gGCT在GDM的诊断及治疗方案的预测方面均有重要价值。  相似文献   
28.
AIMS: To estimate the prevalence of diabetes mellitus with three diagnostic criteria (WHO-1985 and 1999 and ADA-1997), evaluate their concordance and analyse the sensitivity and specificity of the different screening strategies for diabetes. METHODS: A cross-sectional population study with two-step sampling. One thousand and 34 people were selected randomly. A 75-g oral glucose tolerance test (OGTT) was performed and venous blood samples were obtained fasting and at 2 h. RESULTS: The prevalence of known Type 2 diabetes mellitus (DM-2) is 4%[95% confidence interval (CI) 2.8, 5.1]. By WHO-1985 criteria the prevalence of unknown DM-2 is 5.9% (4.5, 7.4); by ADA-1997 criteria 3.5% (2.5, 4.6) and by WHO-1999 criteria 7.3% (5.8, 8.8). Diagnostic overlap and statistical concordance (coefficient K) are WHO-1985/ADA-1997 29.3%, K=0.42; WHO-1985/WHO-1999 80%, K=0.88; ADA-1997/WHO-1999 48%, K=0.63. If only fasting glucose was used (following ADA-1997), 36.3% of those with diabetes (2-h glucose > or =11.1 mmol/l) would be diagnosed. If OGTT was performed (i) in those with a fasting glucose between 6.1 mmol/l and 6.9 mmol/l (9.8% of the population) we would diagnose 66.6%, and (ii) in all those between 5.7 mmol/l and 6.9 mmol/l (18.9% of the population) 81.8% would be diagnosed. CONCLUSIONS: The ADA criteria decrease the prevalence of DM in the adult population of Asturias by 2.4% and concordance with the classical criteria (WHO-1985) was only 29.3%. Using fasting glucose only (ADA-1997) diagnoses 36.3% of those with diabetes. The recent recommendations of the WHO-1999 increases this to 66.6%. To improve the diagnostic strategy for diabetes and detect up to 81.8% of patients, we propose the use of OGTT for all those with a fasting glucose between 5.7 mmol/l and 6.9 mmol/l.  相似文献   
29.
Summary Five compounds which were identified as potential new anticancer drugs inin vitro screening with the human tumor colony forming assay were selected for further evaluation usingin vitro andin vivo models of human ovarian cancer. Three of five compounds were found to inhibitin vitro colony formation of ovarian cancer cell lines derived from both untreated and combination chemotherapy refractory patients. One compound was also found to prolong survival in a human ovarian carcinoma xenograft model system. This compound, chloroquinoxaline sulfonamide, was selected for development and has shown preliminary indication of activity in phase I clinical testing.  相似文献   
30.
Summary: Some of the properties of 4–bromobenzalde-hyde semicarbazone (compound IV), a prototype molecule of a new class of anticonvulsants, aryl semicarbazones, are described. Compound IV demonstrated activity in the maximal electroshock (MES) and subcutaneous pentylenetetrazol (scPTZ) tests in mice, with low neurotoxicity. When given orally to rats, it displayed high potency in the MES test and very low neurotoxicity, resulting in a high protective index (PI). Compound IV displayed no proconvulsant properties, and development of rapid tolerance was not noted. When administered intraperitoneally (i.p.) at doses of 100, 300, or 600 mg/kg to rats, compound IV had no effect on levels of γ-aminobu-tyric acid (GABA) or on GABA-T activity in whole brain. When tested in vitro, compound IV had no effect on rat brain GABA-T at a drug concentration of 100 μM. Although the activities of certain drug-metabolizing enzymes were increased after oral administration of compound IV to rats, these effects were less prominent than those of phenytoin (PHT) and carbamazepine (CBZ). The principal mode of action of compound IV does not appear to be an interaction with the GABAA receptor complex, and other mechanisms, involving excitatory amino acid neurotransmission, will have to be considered in future investigations of the anticonvulsant activity of this compound.  相似文献   
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