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The definition of the persistent vegetative state (PVS) is relatively straightforward, but its diagnosis can be challenging. We reviewed a series of EEG performed in patients with PVS to assess the diagnostic value of EEG. We reviewed records of all hospital patients with a diagnosis of persistent vegetative PVS. EEG findings included normal, continuous generalized slowing, intermittent generalized slowing, background slowing, background suppression, alpha, generalized periodic pattern, PLEDS, and triphasic waves. EEG findings had no association with etiology and varied from one pattern to another in the same patients' EEGs obtained at different times (see table). We conclude that EEG findings in PVS are heterogeneous and too variable to be of diagnostic value.  相似文献   
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The present study deals with the in vitro and in vivo effects of methyl isocyanate (MIC) on rat brain mitochondrial function. Addition of MIC to tightly coupled brain mitochondria in vitro resulted in a mild stimulation of state 4 respiration, abolition of respiratory control, decrease in ADP/O ratio, and inhibition of state 3 oxidation. The oxidation of NAD+-linked substrates (glutamate + malate) was more sensitive (fourfold) to the inhibitory action of MIC than succinate while cytochrome oxidase was unaffected. Administration of MIC subcutaneously at a lethal dose affected respiration only with glutamate + malate as the substrate (site I) and caused a 20% decrease in state 3 oxidation leading to a significant decrease in respiratory control index while state 4 respiration and ADP/O ratio remained unaffected. As both the malondialdehyde and iron contents of brain mitochondria were not altered, it may be inferred that the observed in vivo inhibition of state 3 oxidation is induced by MIC through systemic stagnant hypoxia leading to ischemia of brain, which further contributes to the cerebral hypoxia.  相似文献   
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The regulatory role of vitamin D receptor (VDR) gene variants of Bsm I, Apa I, Taq I, and Fok I polymorphisms on vitamin D(3)-modulated macrophage phagocytosis with live Mycobacterium tuberculosis and lymphoproliferative response to M. tuberculosis culture filtrate antigen (CFA) was studied in patients with pulmonary tuberculosis (n = 46) and in normal healthy subjects (NHS) (n = 64). Vitamin D(3) at a concentration of 1 x 10(-7) M enhanced the phagocytic potential of normal subjects who had a phagocytic index of less than 20%. This increase was seen in subjects with the genotypes BB (p = 0.017), AA (p = 0.016), tt (p = 0.034), and FF (p = 0.013) and the extended genotype BBAAtt (p = 0.034). Normal subjects with BBAAtt performed better phagocytosis than individuals with bbaaTT genotype (p = 0.034). Vitamin D(3) at 10(-9), 10(-8), and 10(-7) M concentrations suppressed the lymphoproliferative response to CFA antigen in normal subjects. This decreased lymphocyte response was observed in normal individuals with the genotypes BB (p = 0.0009), tt (p = 0.016), and FF (p = 0.008) and the extended genotype BBAAtt (p = 0.02). Addition of vitamin D(3) had no significant effect on macrophage phagocytosis and lymphoproliferative response to CFA in pulmonary TB patients. This may be due to the unresponsive nature of the cells to the action of vitamin D(3) or the downregulated VDR expression by virtue of the disease, which renders them inactive. The genotypes BB, tt, and the extended genotype BBAAtt may be associated with increased expression of VDR which in turn regulate the action of vitamin D(3) and modulate the immune functions to M. tuberculosis in NHS.  相似文献   
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To determine hepatitis B virus genotype and subtype distribution among HBV infected individuals with different clinical manifestations in western India, serum samples from 19 asymptomatic hepatitis B surface antigen carriers, 30 chronic hepatitis B patients, 8 acute hepatitis B patients, 5 fulminant hepatitis B patients, and with circulating HBV DNA were genotyped and subtyped on the basis of the nucleotide sequence analysis of S region of the HBV genome. Genotype D was the predominant genotype circulating in western India (57/62; 91.93%). All 19 asymptomatic hepatitis B surface antigen carriers, 8 acute hepatitis B patients, 5 fulminant hepatic failure patients and 25/30 chronic hepatitis B patients were circulating genotype D and ayw3/ayw2 subtypes. HBV genotype A was prevalent in 8% (5/62) of the total number of patients and all belonged to chronic hepatitis B category. Subtyping analysis showed that all genotype A isolates were of subtype adw2. As most of the patients from different clinical categories were infected with HBV genotype D, it is concluded that this genotype did not influence the outcome of HBV infection.  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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