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1.
Behavioral and cognitive-behavioral approaches to chronic pain are receiving increasing attention from researchers and clinicians. This article reviews and highlights recent research advances and future research directions. Assessment research reviewed includes studies examining the social context of pain, the relationship of chronic pain to depression, cognitive variables affecting pain, and comprehensive assessment measures. Treatment outcome studies reviewed are those evaluating the effects of behavioral and cognitive-behavioral treatments for chronic pain. These studies focus on comparisons of behavioral treatment with control conditions, comparisons of two behavioral treatments, and prevention of chronic pain. Future directions for assessment and treatment research are outlined.  相似文献   
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Intestinal schistosomiasis japonica: CT-pathologic correlation   总被引:1,自引:0,他引:1  
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The development and application of fluorescence in-situ hybridization (FISH) has opened the way for comprehensive studies on numerical chromosome abnormalities in human spermatozoa. FISH can be rapidly applied to large numbers of spermatozoa and thus overcomes the major limitation of karyotyping spermatozoa after penetration of zona-free hamster oocytes. The simultaneous hybridization of two or more chromosome-specific probes to spermatozoa and subsequent detection of the bound probes using different fluorescent detection systems enables two or more chromosomes to be localized simultaneously in the same spermatozoon and provides a technique for undertaking reasonable estimates of aneuploidy. The most commonly used probes are those which bind to the centromeric region of specific chromosomes. Most studies to date have concentrated on estimating aneuploidy in spermatozoa from normospermic men, although reports are beginning to appear on aneuploidy in spermatozoa from subfertile and infertile men. Multi- probe FISH studies have generally reported disomy (hyperhaploidy) estimates of 0.05-0.2% per chromosome. There is preliminary evidence that some chromosomes such as X, Y and 21 are predisposed towards higher rates of non-disjunction during spermatogenesis. There are also suggestions of inter-donor variability in aneuploidy frequencies for specific chromosomes, although this requires confirmation in larger studies. While FISH is clearly a powerful technique that has many applications in reproductive medicine, it must also be realized that it does have limitations and the technology itself is still evolving and has yet to be fully validated on spermatozoa.   相似文献   
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Leukemia remains the most common cancer in childhood, and while great strides have been made in increasing event-free survival in the past 20 years, patients with high-risk features still pose a challenge for successful disease-free survival. Older children and adolescents are included in that high-risk group. Approximately 80-85% of cases of leukemia in the pediatric population are of the lymphocytic subtype. Overall disease-free survival rates for acute lymphocytic leukemia have increased to 80% for those with standard or low-risk disease and 65-70% for those with high-risk disease. This is a product of both a better understanding of the molecular pathophysiology of ALL and the development of better treatment strategies based on risk. In acute myelogenous leukemia, we have not achieved such success, and disease-free survival rates are in the 30-40% range. This article discusses the diagnosis of leukemia in the adolescent population with attention to pathogenesis, prognostic risk factors, therapy, outcome, and late effects of acute lymphocytic leukemia.  相似文献   
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We examined the relationship between a functional polymorphism (667C-- >T, ala-->val) of the methylenetetrahydrofolate reductase gene (MTHFR) and the risk of colorectal adenomas in the prospective Nurses' Health Study. Among 257 incident polyp cases and 713 controls, the MTHFR val/val polymorphism [relative risk (RR) = 1.35, 95% confidence interval (CI) 0.84-2.17] was not significantly associated with risk of adenomas. This lack of association was observed for both small (RR = 1.36, 95% CI 0.76-2.45) and large (RR = 1.32, 95% CI 0.66-2.66) adenomas. Furthermore, there was no significant interaction between this polymorphism and consumption of either folate, methionine or alcohol. We also examined the relationship of a newly identified polymorphism (asp919gly) of the methionine synthase gene (MS) with the risk of colorectal adenomas in the same population. The MS gly/gly polymorphism was also not significantly associated with risk of colorectal adenomas (RR = 0.66, 95% CI 0.26-1.70). These results, which need to be confirmed in other studies, suggest that the MTHFR val/val polymorphism, which has been previously inversely associated with risk of colorectal cancer, plays a role only in a late stage (adenoma-- >carcinoma) of colorectal tumorigenesis, and/or may protect against malignant transformation in the subset of benign adenomas, which may progress to malignancy.   相似文献   
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