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RNA interference (RNAi) is a flexible gene silencing mechanism that responds to double-stranded RNA by suppressing homologous genes. Here, we report the characterization of RNAi effector complexes (RISCs) that contain small interfering RNAs and microRNAs (miRNAs). We identify two putative RNA-binding proteins, the Drosophila homolog of the fragile X mental retardation protein (FMRP), dFXR, and VIG (Vasa intronic gene), through their association with RISC. FMRP, the product of the human fragile X locus, regulates the expression of numerous mRNAs via an unknown mechanism. The possibility that dFXR, and potentially FMRP, use, at least in part, an RNAi-related mechanism for target recognition suggests a potentially important link between RNAi and human disease.  相似文献   
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Acute porphyria is rare in orientals. We describe a Chinese woman with recurrent generalised tonic-clonic seizures and abdominal pain. Genomic DNA studies identified a heterozygous base substitution from guanine to adenine at nucleotide position 503, resulting in substitution of arginine by histidine at position 168 of the protein (R168H). This genetic abnormality is similar to the mutation reported in Caucasians with variegate porphyria. To the best of our knowledge, this is the first report in the English literature a Chinese patient with variegate porphyria with an identifiable mutation. A brief review of porphyria is presented.  相似文献   
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OBJECTIVES. To describe a theoretic approach and rationale for the integration of health protection and health promotion in worksite cancer prevention programs and to describe an intervention study designed to implement this integration. METHODS. Twenty-four worksites were recruited to participate in this randomized, controlled study. The theoretically based intervention model integrates health promotion and health protection through (1) joint worker-management participation in program planning and implementation, (2) consultation on worksite changes, and (3) educational programs targeting health behavior change. RESULTS. Although the primary purpose of this paper is to describe a theoretic approach to the integration of health promotion and health protection, preliminary results are also noted. In these predominantly manufacturing worksites, many workers faced the double jeopardy of exposures to occupational carcinogens and personal risks such as smoking or poor dietary habits. Production workers' job responsibilities frequently limited their full participation. Barriers to participation were identified early in the project, and strategies were developed to facilitate maximal worker involvement and worksite changes. CONCLUSIONS. Lifestyle changes such as smoking cessation or dietary changes may be more effectively promoted among blue collar audiences when programs also encourage management actions to reduce occupational exposures. Public health professionals trained in health promotion and health protection must work together to effectively address the health concerns of this population.  相似文献   
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This article details a practice protocol for the examination and reporting of specimens removed from patients with carcinoma of the urinary bladder, ureter, renal pelvis, or urethra. It was created by a multidisciplinary task force of pathologists and oncologists established by the Cancer Committee of the College of American Pathologists. Documentation for the protocol was obtained from the previously published protocol, the medical literature, personal experience, and consultation with colleagues. After creation and review by the task force, the protocol was sent to 1000 randomly selected practicing pathologists as a survey. Their comments and suggestions were addressed in the final version. The protocol was approved by the Board of Governors of the College of American Pathologists.  相似文献   
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