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OBJECTIVE: This study directly compared the clinical validity of 11 empirically defined alcoholism typologies to determine whether some typologies are clinically more valid than others. METHOD: A sample of 360 hospitalized alcoholic men were extensively evaluated at entry into the study and again 1 year later. Twenty-three measures of clinical validity were employed; 15 were postdictive and 8 were predictive. Postdictive retrospective measures obtained at entry into the study included family history, age of onset and lifetime course characteristics associated with alcoholism severity, general psychopathology and psychosocial functioning. Predictive outcome measures drawn from information obtained during the 1-year follow-up included: abstinence, alcoholism severity and clinician ratings of outcome. The measures were subjected to various statistical analyses, including factor analysis. RESULTS: We found that all of the alcoholism typologies met at least 7 of the 23 a priori measures of clinical validity. The correlations between these conceptually and methodologically disparate typologies were often striking. Exploratory factor analysis, which explained 35% of the variance, suggested three possible underlying dimensions to account for the overlap among typologies: (1) age and its correlates, including age-of-alcoholism onset; (2) "pure" alcoholism versus psychiatrically heterogeneous alcoholism that encompassed antisocial personality disorder; and (3) current severity of psychiatric distress, impairment and dysfunction. CONCLUSIONS: No single method of subtyping alcoholics clearly emerged as superior. All demonstrated some degree of predictive and postdictive clinical validity. Most methods of subtyping correlated positively with each other at moderate, but typically significant, levels.  相似文献   
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PURPOSE: To develop a genome-based classification scheme for clear-cell sarcoma (CCS), also known as melanoma of soft parts (MSP), which would have implications for diagnosis and treatment. This tumor displays characteristic features of soft tissue sarcoma (STS), including deep soft tissue primary location and a characteristic translocation, t(12;22)(q13;q12), involving EWS and ATF1 genes. CCS/MSP also has typical melanoma features, including immunoreactivity for S100 and HMB45, pigmentation, MITF-M expression, and a propensity for regional lymph node metastases. MATERIALS AND METHODS: RNA samples from 21 cell lines and 60 pathologically confirmed cases of STS, melanoma, and CCS/MSP were examined using the U95A GeneChip (Affymetrix, Santa Clara, CA). Hierarchical cluster analysis, principal component analysis, and support vector machine (SVM) analysis exploited genomic correlations within the data to classify CCS/MSP. RESULTS: Unsupervised analyses demonstrated a clear distinction between STS and melanoma and, furthermore, showed that CCS/MSP cluster with the melanomas as a distinct group. A supervised SVM learning approach further validated this finding and provided a user-independent approach to diagnosis. Genes of interest that discriminate CCS/MSP included those encoding melanocyte differentiation antigens, MITF, SOX10, ERBB3, and FGFR1. CONCLUSION: Gene expression profiles support the classification of CCS/MSP as a distinct genomic subtype of melanoma. Analysis of these gene profiles using the SVM may be an important diagnostic tool. Genomic analysis identified potential targets for the development of therapeutic strategies in the treatment of this disease.  相似文献   
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Mautes AE  Noble LJ 《Brain research》2000,883(2):233-237
HSP70 and heme oxygenase-1 (HO-1) are thought to be markers of cell injury and oxidative stress, respectively. We have immunolocalized these proteins in the spinal cord at 1-14 days after contusion. HSP70 and HO-1 were co-induced in glia and macrophages within the injured segment at all time points. This co-induction may reflect complementary functions that serve to protect these cells as they respond to the postcontusional environment.  相似文献   
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It has been previously suggested that morphine can regulate the expression and function of some proteins of the cytoskeleton. In the present study, we used real-time quantitative polymerase chain reaction to examine the effects of chronic morphine administration, in rat striatum, on 14 proteins involved in microtubule polymerization and stabilization, intracellular trafficking, and serving as markers of neuronal growth and degeneration. Chronic morphine treatment led to modulation of the mRNA level of seven of the 14 genes tested. Glial fibrillary acidic protein (Gfap) and activity-regulated cytoskeleton-associated protein (Arc) mRNA were upregulated, while growth associated protein (Gap43), clathrin heavy chain (Cltc), alpha-tubulin, Tau, and stathmin were downregulated. In order to determine if the regulation of an mRNA correlates with a modulation of the expression of the corresponding protein, immunoblot analyses were performed. With the exception of Gap43, the levels of Cltc, Gfap, Tau, stathmin, and alpha-tubulin proteins were found to be in good agreement with those from mRNA quantification. These results demonstrate that neuroadaptation to chronic morphine administration in rat striatum implies modifications of the expression pattern of several genes and proteins of the cytoskeleton and cytoskeleton-associated components.  相似文献   
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Until recently, the primary use of preimplantation genetic diagnosis (PGD) has been the selection of embryos to avoid lethal or debilitating gene mutations or abnormal chromosome complement. PGD can be used to reduce the risk of transferring to the uterus an embryo with Down syndrome, and parents who are carriers of severe genetic diseases may choose to avoid having children with these debilitating genetic conditions. The use of PGD is now being extended to include gene mutations that increase the risk of late-onset disorders such as breast and ovarian cancer. This paper argues for caution in advocating reproductive methods that are costly, have a limited chance of success, and for which the long-term outcome is unknown. Counselling should allow women a true choice of declining the option of PGD without recrimination, feelings of guilt or social pressure. There is concern that the Human Fertilisation and Embryology Authority has approved extension of PGD to late-onset multifactorial diseases without clear guidelines for its use. Guidelines for embryo selection should be revised to deal with potential conflict between reproductive success and genetic screening for disorders that do not profoundly affect the embryo or the children.  相似文献   
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Fetal therapy raises ethical concerns in relation to the balance of potential benefit and harm, autonomy and informed consent, and the duties of the clinician to the pregnant women and fetus. Invasive therapy should be recommended only when it has a realistic chance of saving the life of the fetus and offspring or preventing serious and irreversible disease or disability. Clinicians should respect maternal choice and assessment of risk, particularly if the therapy might be only partially successful, leaving the offspring with a profound morbidity. Fetal therapy should not be undertaken without maternal consent; nor should it be presented coercively as an option to avoid a termination of pregnancy. Therapeutic procedures of unproven efficacy should be undertaken only with the voluntary informed consent of the pregnant woman and according to a clearly defined research protocol that has been approved by an appropriate research ethics committee and where appropriate support and counselling can be provided.  相似文献   
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