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31.
Using a combination of avidin-biotin microELISA and solid phase radioimmunoassay, we examined sera from 23 patients with systemic lupus erythematosus (SLE), two patients with established sensitivity to ingested shrimp, and 15 healthy normal subjects. In addition to IgG antibodies, varying amounts of IgE antibodies specific for native DNA (nDNA), denatured or single-stranded DNA (dnDNA), RNA, and tRNA were demonstrable in the sera of SLE patients, but not in the sera of normal subjects. A comparison of the specificity of nucleic acid-specific IgE antibodies present in the sera of shrimp-sensitive patients with those present in the sera of seven SLE patients revealed that the IgE antibodies in the sera of shrimp-sensitive patients specifically recognized shrimp tRNA but not yeast tRNA, calf thymus RNA, or calf thymus DNA, while those present in the sera of patients with SLE recognized all these nucleic acid antigens. The IgE antibodies directed against nDNA, dnDNA, RNA, and tRNA may mediate mast cell and basophil degranulation and thus contribute both to immediate-type hypersensitivity phenomena including hives seen in patients with SLE and to the localization of IgE-nucleic acid complexes in target tissues.  相似文献   
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The susceptibility of experimental rats to Aflatoxin B1, a well known hepatocarcinogen, during chronic food restriction was studied, using a few putative preneoplastic biochemical markers. Gamma-Glutamyl transpeptidase was the most sensitive among the various enzymes studied, at the dose of 10 micrograms/day/100 gm body weight of Aflatoxin B1 fed over a period of three weeks after a twelve chronic food restriction in experimental rats. It was significantly elevated in the underfed untreated group, thus suggesting that preneoplastic changes may be precipitated during chronic undernutrition and carcinogen exposure.  相似文献   
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Patients can develop malignancies due to various reasons including genetic factors, chemical carcinogens, radiation, and defects in their immune system. The immune system is postulated to carry out routine surveillance for malignancy. Patients who have defective immune responses may be susceptible to malignancies due to complicated underlying mechanisms. These include defective immune response to cancer-causing bacteria, transforming viruses, and concomitant molecular, cellular and immunoregulatory defects. Common variable immune deficiency (CVID) is characterized by hypogammaglobulinemia, impaired antibody responses and an increased susceptibility to infections. A disorderly immune response, or immune dysregulation, may also lead to autoimmune complications and possibly to malignancy. The treatment of CVID involves infusion of replacement doses of immunoglobulin, either intravenously (IGIV) or subcutaneously (SCIG). However, it is unclear whether adequate replacement of immunoglobulins is sufficient to prevent the increased risk of malignancy seen in this disease. We present two cases of unusual solid tumors complicating CVID treated with adequate doses of intravenous immunoglobulins. In this study we review the occurrence of malignancy in patients with CVID and postulate mechanisms that may be involved indigent to this disease. We will also review the role of replacement immunoglobulin and discuss cancer screening in these high risk individuals.  相似文献   
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The isolation and structure elucidation of two cyclic peptides, pahayokolides A (1) and B (2), is described. Structural features determined for these compounds include a pendent N-acetyl-N-methyl leucine, both E- and Z-dehydrobutyrines, a homophenylalanine, and an unusual polyhydroxy amino acid that is most likely of mixed polyketide synthase/nonribosomal peptide synthase origin. These peptides were purified from a new species of cyanobacteria of the genus Lyngbya, which was isolated from a periphyton mat from the Florida Everglades.  相似文献   
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The Upanayan programme is a product of Indchem Research and Development Laboratory, a scientific association recognized by Government of India, Ministry of Science and Technology. The objective of the project was to develop a computer assisted programme for the training of persons with mental retardation. The project was executed by an inter disciplinary team of experts. The focus of the training programme is the mother who is the intervening agent. The programme, developed in the first phase of the project, is an expert system for the infant stimulation and early intervention process for children below 2 years of age with the disability. The system comprises of: (i) a development check list of skills for assessment and programming, (ii) a profile to record the observations, (iii) intervention strategies in the form of activities to acquire all the skills in the check list. The programme is designed for the Indian socio-economic conditions and is available in the form of a printed manual, and also as a computer software. The two can be used independently of each other. The programme has been translated into Hindi, Tamil, Malayalam and Marathi. With this programme as the basis, a centre for early intervention, Madhuram Narayanan Centre for Exceptional Children—was set up in Madras about 3 years back. Presently 210 children are receiving training there. The Centre has evolved intervention strategies based on parental involvement, with salutary effect on the parents as well as on the children.  相似文献   
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Development of a detector case for complete co-registration of images in a non-fiber-based combined near-infrared spectral tomography and digital breast tomosynthesis, required analysis to find materials that could support a breast under full mammographic compression without affecting the x-ray images or the quality of the near infrared measurements. Several possible solutions were considered, and many types of plastics were tested in the development of the detector case. Light channeling within the detector case changed the data obtained in resin and agarose phantoms, lowering recovered absorption values. Additional developments focusing on blocking stray light were successful and permitted a normal subject imaging exam.OCIS codes: (120.3890) Medical optics instrumentation, (170.0110) Imaging systems, (170.3830) Mammography  相似文献   
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