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41.
42.
Randomized trial of breast self-examination in Shanghai: methodology and preliminary results 总被引:3,自引:0,他引:3
DB Thomas DL Gao SG Self CJ Allison Y Tao J Mahloch R Ray Q Qin R Presley P Porter 《Canadian Metallurgical Quarterly》1997,89(5):355-365
BACKGROUND: The efficacy of breast self-examination in helping to reduce mortality from breast cancer has not been rigorously demonstrated. PURPOSE: To assess efficacy, a large, randomized trial was initiated in Shanghai, China. METHODS: From October 1989 to October 1991, 267040 current and retired female employees associated with 520 factories in the Shanghai Textile Industry Bureau were randomly assigned on the basis of factory to either a self-examination instruction group (133375 women) or a control group (133665 women). The women were born within the period from 1925 through 1958. Women in the instruction group were given intensive training in breast self-examination, including the use of silicone breast models and personalized instruction, plus two subsequent reinforcement sessions and multiple reminders to practice the technique. Women in the control group were asked to attend training sessions on the prevention of low back pain. All women have been followed for the development of breast diseases and for death from breast cancer. RESULTS: A high level of participation during the first 4-5 years of the trial was documented among women in the instruction group. Randomly sampled women in this group demonstrated greater proficiency in detecting lumps in breast models than did randomly sampled women in the control group. Approximately equal numbers of breast cancers were detected in the two groups (331 in the instruction group and 322 in the control group) through 1994, which is the last year for which case-finding efforts have been completed. The breast cancers detected in the instruction group were not diagnosed at an appreciably earlier stage or smaller size than those in the control group. More benign breast lesions were detected in the instruction group than in the control group (1457 versus 623, respectively), suggesting a higher index of suspicion for women who received training. Cumulative breast cancer mortality rates through 5 years from entry into the study were nearly equivalent for the two groups. CONCLUSIONS: Breast self-examination has not led to a reduction in mortality from breast cancer in this study cohort in the first several years since the trial began. A shift toward the diagnosis of disease at a less advanced stage in women given instruction has also not been demonstrated. Longer follow-up of participants in this trial is required before final assessment can be made of the efficacy of breast self-examination. IMPLICATIONS: At this time, there is insufficient evidence to recommend for or against the teaching of breast self-examination. 相似文献
43.
CJ Martin 《Canadian Metallurgical Quarterly》1997,68(12):775-781
BACKGROUND: The most common cause of a sudden onset of painful proptosis with diplopia in an otherwise healthy adult is orbital pseudotumor. However, there are other conditions that mimic this presentation and must be ruled out with laboratory testing and imaging studies. CASE REPORT: A 41-year-old Hawaiian man sought treatment for an acute, progressive, painful, left ophthalmoplegia without exophthalmos. During the next week, a loss of accommodation and associated pupillary reaction, decreased visual acuity, color vision deficits, and a paracentral scotoma developed. CT and MRI revealed a mass in the orbital apex. All systemic findings were negative, and high-dose systemic steroid therapy was initiated. Symptoms resolved within hours of the first dose, and signs were completely absent 1 month later. Follow-up MRI revealed complete absence of the previously noted mass. CONCLUSION: This is an atypical case of orbital pseudotumor, since there was no exophthalmos. It was diagnosed by clinical presentation, laboratory and imaging studies, and response to therapy. 相似文献
44.
CJ Moerman HB Bueno de Mesquita FW Smeets S Runia 《Canadian Metallurgical Quarterly》1995,24(6):591-602
BACKGROUND: Gallstones and obesity have been suggested as risk factors for cancer of the biliary tract. Since both factors are related to diet, we studied the relationship between dietary intake and the cancer of interest in a population-based case-control study. METHODS: The study population comprised 111 patients and 480 controls. Food intake was assessed by means of a semiquantitative food frequency questionnaire. Estimates of the intake of foods and micronutrients were obtained from cases and controls themselves (direct respondents) or from relatives (indirect respondents). Participants were categorized into tertiles of intake. Risk ratios were estimated by logistic regression analysis. RESULTS: The major findings are a monotonic decrease in risk associated with the consumption of vegetables (ORs 1.0, 0.7, 0.4, P value trend < 0.01) and a monotonic increase in risk associated with sugar added to drinks and desserts (ORs 1.0, 1.3, 2.5; P value trend < 0.01). CONCLUSIONS: The finding on added sugar corresponds to our earlier report that the group monosaccharides and disaccharides is a potential risk factor for this cancer. Sugar may influence bile composition through lipoprotein metabolism. The protective effect of vegetables is in accordance with the reported inverse relationship between vegetables and many epithelial cancers of the alimentary tract. 相似文献
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47.
Hyperdynamic circulation of cirrhotic rats: role of substance P and its relationship to nitric oxide
CJ Chu FY Lee SS Wang FY Chang YT Tsai HC Lin MC Hou SL Wu CC Tai SD Lee 《Canadian Metallurgical Quarterly》1997,32(8):841-846
BACKGROUND: It has been suggested that excessive formation of nitric oxide (NO) is responsible for the hyperdynamic circulation observed in portal hypertension. Substance P is a neuropeptide partly cleared by the liver and causes vasodilatation through the activation of the endothelial NO pathway. However, there are no previously published data concerning the plasma level of substance P in cirrhotic rats and its relationship to NO. METHODS: Plasma concentrations of substance P and nitrate/nitrite (an index of NO production) were determined in control rats and cirrhotic rats with or without ascites using an enzyme-linked immununosorbent assay and a colorimetric assay, respectively. In addition, systemic and portal hemodynamics were evaluated by a thermodilution technique and catheterization. RESULTS: Cirrhotic rats with and without ascites had a lower systemic vascular resistance (2.6 +/- 0.2 and 3.9 +/- 0.4 mmHg ml(-1) x min x 100 g body weight, respectively) and higher portal pressure (14.6 +/- 0.6 and 11.3 +/- 1.8 mmHg) than control rats (6.5 +/- 0.3 mmHg x ml(-1) x min x 100 g BW and 6.8 +/- 0.2 mmHg, respectively, P < 0.05), and cirrhotic rats with ascites had the lowest systemic vascular resistance. Plasma levels of nitrate/nitrite progressively increased in relation to the severity of liver dysfunction (control rats, 2.7 +/- 0.5 nmol/ml; cirrhotic rats without ascites, 5.6 +/- 1.3 nmol/ml; cirrhotic rats with ascites, 8.3 +/- 2.2 nmol/ml; P < 0.05). Cirrhotic rats with ascites displayed higher plasma values of substance P (57.7 +/- 5.9 pg/ml) than cirrhotic rats without ascites (37.9 +/- 3.1 pg/ml, P < 0.05) and control rats (30.1 +/- 1.0 pg/ml, P < 0.05). There was no significant difference in plasma substance P values between control rats and cirrhotic rats without ascites (P > 0.05). No correlation was found between plasma levels of substance P and nitrate/nitrite (r = 0.318, P > 0.05). CONCLUSIONS: Excessive formation of NO may be responsible, at least partly, for the hemodynamic derangements in cirrhosis. Although substance P may not participate in the initiation of a hyperdynamic circulation in cirrhosis, it may contribute to the maintenance of the hyperdynamic circulation observed in cirrhotic rats with ascites. 相似文献
48.
Reduction of residual stress in montmorillonite/epoxy compounds 总被引:2,自引:0,他引:2
An epoxy resin was cured while in intimate contact with small amounts of epoxyphilic montmorillonites. It was determined that cured epoxy exists within the montmorillonite interlayer by the observation of very high interlayer spacings, even greater than 8 nm, Generally, epoxy compounds containing montmorillonites that had been swollen in the curing agent prior to curing exhibited larger interlayer spacings, especially among the non-dispersed montmorillonite layers. The maximum observed residual stress was reduced by greater than 50% in the epoxyphilic montmorillonite/epoxy compounds over that of the pure epoxy. The epoxyphilic montmorillonite/epoxy compounds generally exhibited higher values of glass transition temperature, flexural modulus, and ultimate flexural strength than the pure epoxy. The tyramine-montmorillonite compounds typically had the highest values overall. 相似文献
49.
An impassioned debate over the virtues and dangers of dieting is polarizing the field and diverts attention from key issues. Dieting clearly has costs and, for some, has the potential for benefit. The primary challenges are (1) to identify individuals who will be helped or harmed by dieting, (2) to reduce the frequency and severity of dieting in those for whom the costs exceed the benefits, (3) to better understand the physiological and psychological reasons why some people can lose and others cannot, and (4) to develop safe and effective means for weight loss and its maintenance and to target these methods to individuals who stand to benefit. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
50.