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1.
Alterations in tissue zinc levels have been documented in patients with gastrointestinal tract malignancies and more frequently, in those with colonic cancer. However, the precise role of tissue zinc in carcinogenesis is not well elucidated. This study, using a well-established colon cancer model in rats, was designed to investigate the relationship of tissue zinc to the carcinogenic process. The aim was to examine tissue zinc levels in the preneoplastic tissues and to study the changes that occur during transition of mucosa from normal to preneoplastic state. Six-week old rats were given a single dose subcutaneous injection of azoxymethane (AOM) (30mg/kg body weight) and sacrificed after 1, 2, 5, and 9 months of the treatment. Plasma zinc levels showed a significant decrease (p<0.05) at 9 months compared with controls. Tissue zinc levels showed a significant decrease in the large intestine at 1 and 2 months (p<0.05) and at 5 and 9 months (p<0.01), in the small intestine at 2, 5, and 9 months (p<0.05), and in the stomach at 5 and 9 months (p<0.05). The maximum percent decrease (45%) in tissue zinc was observed in the large intestine at 9 months. Tissue copper zinc super oxide dismutase (CuZnSOD) activity was assessed in the body of the stomach, small intestine, and large intestine and compared with the control group. There was a significant fall in CuZnSOD levels in the small intestine at 9 months (p<0.05) and in the large intestine at 5 and 9 months (p<0.01). Two of these six rats showed histological evidence of precancerous lesions in the mucosa of the colon. This study suggests that the decrease in plasma zinc, tissue zinc and activity of CuZnSOD is associated with development of preneoplastic lesions in the colonic mucosa.  相似文献   
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Until recently, the majority of HLA class I typing has been performed by serology. Expensive commercial typing trays are frequently used for testing non-Caucasian subjects and new strategies using DNA-based methods have been adopted for improving clinical histocompatibility testing results and adapted as supplements in proficiency testing. A double-blind comparison of the typing of HLA-B specificities in 40 samples was carried out between serology and two polymerase chain reaction (PCR) methods, PCR amplification with sequence-specific primers (PCR-SSP) and PCR amplification and subsequent hybridization with sequence-specific oligonucleotide probes (PCR-SSOP). The results demonstrated 22.5% misassignments of HLA-B antigens by serology. There was complete concordance between the results obtained with the two PCR based typing methods. A second panel of 20 donor samples with incomplete or ambiguous serologic results was analyzed by PCR-SSP and SSOP. Both PCR methods identified correctly the HLA-B antigens. Our results suggest that more accurate typing results can be achieved by complementing serologic testing with DNA-based typing techniques. The level of resolution for HLA-B antigen assignment can be obtained by this combination of serology and limited DNA-based typing is equivalent to the HLA-B specificities defined by the WHO-HLA Committee. This level of resolution cannot routinely be achieved in clinical histocompatibility testing or in proficiency testing using serologic reagents only.  相似文献   
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Journal of Public Health - This study analyzes a number of diabetic mastopathy cases in long-standing type 1 diabetes to obtain a detailed history and examination findings from these patients and...  相似文献   
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A case of ventricular fibrillation due to butane toxicity after unintentional inhalation of air freshener is reported for its rarity and to create awareness among practitioners and the public. A 25-year-old woman collapsed in the supermarket after unintended exposure to air freshener sprayed into her nostrils. Her husband started cardiopulmonary resuscitation immediately, and she was brought to the hospital. She had coarse ventricular fibrillation. Defibrillation with 360 J was given, and the rhythm reverted to normal sinus rhythm after the third shock. Epinephrine was not administered, and she was treated with esmolol infusion for ventricular ectopy. The patient recovered completely without any sequelae and was discharged on the fifth hospital day. On thin layer chromatography, the chemical content of the spray was identified to be isobutane. Avoiding epinephrine and administering β-adrenergic blockers may protect the catecholamine-sensitized heart early during resuscitation in butane exposure cases.  相似文献   
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We report a case of gas gangrene (GG) in a non-diabetic HIV seronegative man who died within 60 hours following an intramuscular injection in rural India. The occurrence of GG after intramuscular injection is rare and only a few cases have been reported in the published literature.  相似文献   
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