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61.
BACKGROUND: Tobacco smoking is one of the main risk factors for oral, pharyngeal and oesophageal cancers in developed countries. Information on the role of the tar yield of cigarettes in upper digestive tract carcinogenesis is sparse and needs to be updated because the tar yield of cigarettes has steadily decreased over the last few decades. PATIENTS AND METHODS: We analysed two case-control studies, from Italy and Switzerland, conducted between 1992 and 1999, involving 749 cases of oral and pharyngeal cancer and 1770 controls, and 395 cases of squamous-cell oesophageal carcinoma and 1066 matched controls. Odds ratios (ORs) were estimated by unconditional multiple logistic regression models, including terms for age, sex, study centre, education and alcohol consumption. RESULTS: Based on the brand of cigarettes smoked for the longest time, the multivariate ORs for current smokers compared with never smokers were 6.1 for <20 mg and 9.8 for >or=20 mg tar for oral and pharyngeal neoplasms, and 4.8 and 5.4 for oesophageal cancer, respectively. For the cigarette brand smoked in the previous six months, the ORs for >or=10 mg compared with <10 mg were 1.9 for cancer of the oral cavity and pharynx and 1.8 for oesophageal cancer, after allowance for number of cigarettes and duration of smoking. CONCLUSIONS: The present study confirms the direct relationship between the tar yield of cigarettes and upper digestive tract neoplasms, and provides innovative information on lower tar cigarettes, which imply reduced risks compared with higher tar ones. However, significant excess risks were observed even in the lower tar category, thus giving unequivocal indications for stopping smoking as a priority for prevention of upper digestive tract neoplasms.  相似文献   
62.
T-lymphocyte cell function was studied in vitro in peripheral blood mononuclear cells (PBMC) from 61 male patients with head and neck squamous cell carcinomas compared to 46 control patients. Patients older than 80 years or with reduced tumor-related performance status as measured by Karnofsky score less than 75 were excluded. In contrast to previous similar studies, control subjects ensured a minimum stress load by sampling all patients on the day of either diagnostic or therapeutic surgery. PBMC were separated by density-gradient centrifugation and subsequently cultured with autologous sera in vitro. The mitogen concanavalin A (Con A), which stimulates all T-cell clones, was employed. Findings showed that increased Con A stimulation and PBMC proliferation occurred with PBMC from cancer patients compared to that from control patients. In contrast, no differences could be detected with respect to the stimulated supernatant level of interleukin-2, interleukin-4 or interferon-γ between the groups. These results suggest that T-lymphocytes from PBMC are generally affected by neoplastic disease through either a supporting cell or serum factor.  相似文献   
63.
对41例儿童旋毛虫病的临床观察   总被引:5,自引:0,他引:5  
为了解儿童旋毛虫病的临床特征,对1992~1995年就诊的41例儿童旋毛虫病进行分析。结果表明,患儿来自河南6个地区,主要因食猪肉馅饺子、烤羊肉串或食涮猪肉而感染。冬季为本病的高发季节。患儿平均年龄为8.8岁,男女之比为2.71。长期发热和嗜酸性粒细胞增多为本病的主要表现,仅少数患儿有肌痛、胃肠道症状和皮疹。眼睑水肿仅见于发病早期。血清学检查对诊断本病有重要意义。预防本病的关键措施是加强肉检和改变不良的饮食习惯。  相似文献   
64.
目的:比较徒手和卵圆钳两种方法对产后立即放置(IPPI)宫内节育器(IUD)效果的影响。方法:将910例阴道分娩产妇(其中97.7%是首次分娩)随机分成两组,于胎盘娩出后10分钟内放置TCu380AIUD,其中470例徒手放置(手放组),440例用卵圆钳放置(钳放组)。随访12个月,以生命表法统计、χ2检验比较两种放置方法的脱落率、妊娠率、因症取出率等。结果:6和12个月的随访率分别为95.16%和92.64%。910例中未发生子宫穿孔和感染,仅手放组有1例带器妊娠。放置后主要停用原因是脱落,手放组与钳放组12个月的粗累积脱落率分别为15.86/100妇女和15.88/100妇女,因症(出血、疼痛)取出率分别为2.11/100妇女和1.57/100妇女,差异无显著性(P均>0.05)。结论:徒手放置或卵圆钳放置对IPPI的效果无明显影响;TCu380AIUD适合中国妇女产后立即放置。  相似文献   
65.
The objective of this study was to examine the effects of the intakeof dietary fat upon colorectal cancer risk in a combined analysis of datafrom 13 case-control studies previously conducted in populations withdiffering colorectal cancer rates and dietary practices. Original datarecords for 5,287 cases of colorectal cancer and 10,470 controls werecombined. Logistic regression analysis was used to estimate odds ratios (OR)for intakes of total energy, total fat and its components, and cholesterol.Positive associations with energy intake were observed for 11 of the 13studies. However, there was little, if any, evidence of anyenergy-independent effect of either total fat with ORs of 1.00, 0.95, 1.01,1.02, and 0.92 for quintiles of residuals of total fat intake (P trend =0.67) or for saturated fat with ORs of 1.00, 1.08, 1.06, 1.21, and 1.06 (Ptrend = 0.39). The analysis suggests that, among these case-control studies,there is no energy-independent association between dietary fat intake andrisk of colorectal cancer. It also suggests that simple substitution of fatby other sources of calories is unlikely to reduce meaningfully the risk ofcolorectal cancer.  相似文献   
66.
A longitudinal growth study with monthly measurements during the 1st year of life was conducted by nine paediatricians working in private practice in Zurich. Of 92 children, none was lost to the study and only 32 of 1104 planned visits were missed; the quality of the measurements was comparable to that of a specialised university clinic. Compared to the Zurich Longitudinal Growth Studies, children of this study were considerably heavier and taller. In 92% of the subjects, growth velocity was at least once outside the reference range (3rd–97th percentile). For weight increments, the corresponding proportion was 87%. Conclusions The data indicate that current standards for the 1st year of life for the Zurich area might no longer be appropriate and need to be updated. The currently used velocity percentiles based on 3-monthly measurements are not suitable to assess individual height and weight increments calculated from monthly measurements. Received: 9 June 1997 / Accepted in revised form: 21 November 1997  相似文献   
67.
The aim of this study was to investigate the usefulness of contrast-enhanced harmonic power Doppler ultrasound (US) for the detection of residual viable hepatocellular carcinoma (HCC) after treatment with transcatheter arterial chemoembolization (TACE). Forty-seven patients with 68 HCC lesions 1.8–9.5 cm in diameter (mean ± SD 4.3 ± 1.7 cm) underwent contrast-enhanced power Doppler US, in the harmonic mode, before and after treatment with TACE. Unenhanced spiral CT and contrast-enhanced dynamic MR imaging were also performed to help establish the outcome of therapy. Before treatment, intratumoral blood flow signals were detected at contrast-enhanced harmonic power Doppler US in 65 (95 %) of 68 lesions. After TACE, flow signals were no longer detectable in 22 of these 65 lesions, which showed complete response at spiral CT and dynamic MR imaging. In 38 (88 %) of the 43 lesions with partial response, intratumoral flow signals were still identified at contrast-enhanced harmonic power Doppler US. Twenty-eight of these 38 lesions underwent additional treatment with percutaneous ethanol injection (PEI) using contrast-enhanced harmonic power Doppler US guidance. Complete response was seen after PEI in 23 of 28 lesions. Contrast-enhanced harmonic power Doppler US proved useful for assessing the therapeutic effect of TACE on HCC and for guiding additional treatment with PEI in cases of partial response. Received: 25 January 2000; Revised: 21 April 2000; Accepted: 25 April 2000  相似文献   
68.
Enteroclysis is now widely used for examining the jejunum and ileum. The technique is ideal for demonstrating the extent and severity of disorders that cause morphological changes to the small intestine. In this review many non-neoplastic small intestinal disorders as demonstrated by enteroclysis are described and illustrated. Received: 22 June 1999; Accepted: 28 July 1999  相似文献   
69.
RATIONALE AND OBJECTIVES: This study evaluated the efficacy of targeted computed tomographic (CT) angiography in the diagnosis of intracranial internal carotid artery (ICA) disease and compared the results of routine and targeted CT angiography. MATERIALS AND METHODS: Fifty-four patients (24 male and 30 female patients aged 2 months to 87 years) were examined with CT angiography. Digital subtraction angiography (DSA) was performed in 42. CT angiograms were reconstructed with the maximum-intensity projection (MIP) algorithm. Targeted CT angiography was performed by individually reconstructing a single ICA territory. Each ICA was divided into four segments, and findings of routine MIP CT angiography, routine MIP plus targeted CT angiography, and DSA were reviewed independently by two neuroradiologists for vascular lesions involving each segment. Routine and targeted CT angiograms were also evaluated to determine how well both ICAs were visualized. RESULTS: Routine CT angiography was rated good or excellent for ICA visualization in 64% of cases, compared with 81% for targeted CT angiography (P = .0005). The overall agreement between routine CT angiography and DSA and between routine plus targeted CT angiography and DSA was 92% and 94%, respectively. There was no statistically significant difference between the percentages of vascular lesions detected with routine CT angiography alone and with routine plus targeted CT angiography. Both methods tended to show false-positive findings of steno-occlusive disease, but targeted CT angiography showed details of aneurysms and stenotic lesions that were easily overlooked with routine CT angiography alone. CONCLUSION: Routine plus targeted CT angiography, while providing superior image quality, did not have much clinical effect; further assessment may be needed.  相似文献   
70.
This paper presents a cross-sectional survey of subjective quality of life in a sample of 40 Italian patients with disabling mental disorders living in the community. The patients self-rated their quality of life by the Satisfaction with Life Domains Scale. They were satisfied in relation to basic needs, such as housing, food or clothing and appreciated to some extent the services received, but were very unhappy about their income and their intimate sexual relationships. This Italian sample appeared less satisfied than most samples of people with severe mental disorders investigated by the same instrument in other countries. This may be related to the high level of psychopathology and disability shown by patients for whom survival in the community is in itself an achievement. However, lack of money and poor sexual life are common concerns of long-term mentally ill. How to address such problems is a major challenge for community psychiatric services.  相似文献   
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