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11.
Endoscopic biopsies obtained from 275 patients (180 from the upper gastrointestinal tract and 95 from the lower gastrointestinal tract) were studied to compare the accuracy of biopsy imprint cytology and histology in the diagnosis of gastrointestinal lesions, and also to establish the degree of reliability of imprint cytology alone for an early diagnosis of malignancy. Biopsy histology results were found to be correct in 100% cases. Imprint cytology had an overall accuracy of 100%, 96.7%, 95.8% and 95.8% for the diagnosis of malignancies of the oesophagus, stomach, duodenum and colorectum respectively. False negative results were obtained with lymphomas. Regenerative cellular atypia was an important cause for false positive results. It was concluded that imprint cytology can serve as a useful and simple tool for an immediate diagnosis of malignancy. This should be subsequently correlated with histopathology which facilitates exact tumour typing and assessment of tumour invasion.  相似文献   
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Gossypol prevents the liberation of oxygen from oxyhemoglobin and exerts a hemolytic effect on erythrocytes. In excessive dosages of gossypol, an extreme burden is placed upon the respiratory and circulatory organs owing to the reduced oxygen carrying capacity of blood. Chromium protoporphyrin (CrPP) has been shown to either competitively suppress or to significantly ameliorate a variety of naturally occurring or experimentally induced forms of jaundice in animals and man. In this communication, a novel tissue dependent response to gossypol (50 micromol/kg bw) and gossypol in association with CrPP (50 micromol/kg bw) is described. Our results revealed that gossypol stimulated the hepatic, splenic, and renal delta-aminolevulinic acid synthase (ALA-S) activity, the heme biosynthetic enzyme, and simultaneous administration of CrPP and gossypol synergized the gossypol-mediated increase of ALA-S activity. Gossypol was found to be a potent stimulator of heme oxygenase (HMOX) activity in rat liver and kidney to varying degrees. This tissue response contrasted with that of the spleen, where gossypol decreased the activity of the enzyme. In consonance with the increased hepatic and renal HMOX activity, a marked increase was observed in total serum bilirubin concentration in gossypol treated rats. When rats were given CrPP simultaneously with gossypol, the gossypol mediated increase in hepatic and renal HMOX activity was effectively blocked. Furthermore, the increase in enzymatic activity was accomplished by a decline in the total microsomal protein content on gossypol administration. These findings emphasize the toxic effect of gossypol in eliciting increased heme degradation by stimulating HMOX activity in the liver and the kidney and the potential usefulness of CrPP in experimental and perhaps clinical conditions in which hyperbilirubinemia occurs.  相似文献   
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Textile dyes are becoming a growing threat to the environment. This report presents the findings of the study on the toxicity of the textile dye Alizarin Red S on two freshwater microalgae. The acute toxicity assay revealed that 96-h EC50 values of Chlorella vulgaris and Spirulina platensis were 29.81 mg/L and 18.94 mg/L respectively. The pigments chlorophyll-a, b and carotenoids in C. vulgaris on 96-h exposure to the dye were 2.91, 3.29 and 3.01 times lower in analogy to control whereas Spirulina platensis showed 2.89and 2.56 fold decrease in chlorophyll-a and carotenoid content than control. After the test period of 96-h with dye, the protein content of C. vulgaris and S. platensis were 2.33 and 1.77 times lower compared to the control. The growth inhibition rate, pigment as well as the protein content declined in compliance with the rise in dye concentration, which anticipate paradigm about the toxic effects of the textile dye.

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14.
Mice infected with the coronavirus mouse hepatitis virus, strain JHM (JHM) develop a disease that shares many histological characteristics with multiple sclerosis. We previously demonstrated that JHM-infected mice that only have CD8 T cells specific for an epitope not in the virus develop demyelination on specific activation of these cells. Herein we show that this process of bystander T-cell-mediated demyelination is interferon-gamma (IFN-gamma)-dependent. The absence of IFN-gamma abrogated demyelination but did not change T-cell infiltration or expression levels of inflammatory cytokines or chemokines in the spinal cord. These results are consistent with models in which IFN-gamma contributes to CD8 T-cell-mediated demyelination by activation of macrophages/microglia, the final effector cells in the disease process.  相似文献   
15.
At the Institute of Medical Sciences, Banaras Hindu University in Varanasi, India, health workers took anthropometric measurements and hemoglobin level of 196 pregnant women at gestation of 37-41 weeks and of their singleton newborns to detect a combination of maternal nutritional and uterine parameters which could be used to screen mothers at high risk of delivering a low birth weight (LBW) infant ( 2500 g). The maternal anthropometric measurements included pre- and post-delivery weight, height, head and midarm circumference, fundal height, and abdominal girth. Weight, height, head and midarm circumference, and hemoglobin were significantly correlated with birth weight. Pre-delivery weight was better correlated than post-delivery weight with birth weight (r value = 0.4966 vs. 0.3494). The correlation between pre-delivery weight and birth weight remained, even when hemoglobin and one of the uterine parameters were controlled simultaneously. Hemoglobin was an independent significant predictor of birth weight, when all other variables were controlled simultaneously. Both fundal height and abdominal girth were significantly associated with birth weight, when all other variables were controlled simultaneously. Fundal height had a greater difference in means of birth weight than did abdominal girth (960 vs. 871 g). If the fundal height was less than 25 cm, all infants had a LBW. If the fundal height was greater than 35 cm, only one infant had a LBW. The multiple regression equation using pre-delivery weight, hemoglobin, fundal height, and abdominal girth (all independent significant parameters) to estimate birth weight accounted for 70.5% variation. Researchers tested the equation on 118 consecutive full-term singleton newborns. The equation predicted LBW in 32 of the 36 actual LBW deliveries. The estimated birth weights in the 4 actual but missed cases were 2620, 2600, 2566, and 2826 g. This equation can be successfully used to screen pregnant women for LBW.  相似文献   
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Fractures of the proximal humerus are uncommon in young patients.Although bilateral fracture of proximal humerus itself is rare,association with epilepsy and electrocution is frequent.Only one case of traumatic bilateral proximal humerus fracture has been reported in the literature.We report a rare case of bilateral traumatic displaced proximal humerus fractures in a 40 years old male patient,which was treated by means of open reduction and internal fixation with proximal humerus locked pates on both sides and obtained a good functional outcome.  相似文献   
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Introduction  

Combined aortic and mitral valve disease is usually of rheumatic origin. In these patients we often encounter problem of small valve annuli particularly with aortic annulus. It is still debated whether a small prosthesis should be used or aortic root should be enlarged to prevent Patient Prosthesis Mismatch (PPM). This study was undertaken to review our strategy and feasibility of Aortic Root Enlargement (ARE) in patient undergo Double Valve Replacement (DVR) to avoid mismatch without increase in cost of treatment, morbidity or mortality.  相似文献   
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