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861.
Acetaminophen (APAP) a commonly used drug for decrease the fever and pain but is capable to induced hepatotoxicity at over dose. This study was carried out to investigate the effect of APAP on the expression of anti-apoptotic and antioxidative defense genes, and whether aldose reductase over-expressing plasmid capable to protect against APAP-induced oxidative stress and cell death. APAP treatment induced oxidative stress and hepatotoxicity, and significantly increased aldose reductase mRNA and protein expression in mouse hepatocyte (AML-12). Unexpectedly, AML-12 cells over-expressing aldose reductase augmented APAP-induced reduction in cell viability, reactive oxygen species (ROS) production, glutathione (GSH) depletion and glutathione S-transferase A2 expression. Moreover, over-expression of aldose reductase potentiated APAP induced reduction on proliferating cell nuclear antigen, B cell lymphoma-extra large (bcl-xL), catalase, glutathione peroxidase-1 (GPx-1) and abolished APAP-induced B-cell lymphoma 2 (bcl-2) inductions. Further, over-expression of aldose reductase significantly abolished AMP activated protein kinase (AMPK) activity in APAP-treated cells and induced p53 expression. This results demonstrate that APAP induced toxicity in AML-12, increased aldose reductase expression, and over-expression of aldose reductase render this cell more susceptible to APAP induced oxidative stress and cell death, this probably due to inhibition AMPK or bcl-2 activity, or may due to competition between aldose reductase and glutathione reductase for NADPH.  相似文献   
862.
Current citation-based document retrieval systems generally offer only limited search facilities, such as author search. In order to facilitate more advanced search functions, we have developed a significantly improved system that employs two novel techniques: Context-based Cluster Analysis (CCA) and Context-based Ontology Generation frAmework (COGA). CCA aims to extract relevant information from clusters originally obtained from disparate clustering methods by building relationships between them. The built relationships are then represented as formal context using the Formal Concept Analysis (FCA) technique. COGA aims to generate ontology from clusters relationship built by CCA. By combining these two techniques, we are able to perform ontology learning from a citation database using clustering results. We have implemented the improved system and have demonstrated its use for finding research domain expertise. We have also conducted performance evaluation on the system and the results are encouraging.  相似文献   
863.
864.
The analysis of biochemical parameters in 162 patients with various neoplastic disorders along with 50 normal subjects showed significant rise in serum alkaline phosphatase and lactate dehydrogenase as compared to normal subjects. 21 patients with other monoclonal gammopathies which include infection and immunological diseases were also studied. Parameters such as serum calcium, uric acid, total protein, albumin and globulin were also analyzed in 42 (26%) cases of multiple myeloma, 27 (17%) cases of gastro-intestinal malignancies, 22 (14%) cases of urogenital malignancies, 11 (6%) cases of carcinoma breast, 4 (2%) cases of bone tumors, 21 (12%) cases of other monoclonal gammopathies, including 7 (4%) cases of infection and 14 (8%) cases of immunological diseases. The results indicate use of enzymes alkaline phosphatase and lactate dehydrogenase in neoplastic disorders.  相似文献   
865.
Colostrum, the mammary secretion during first 2–4 days of lactation, provides all the essential components of nutrition and passive immunity required by the newborn. Pregnancy induced hypertension (PIH), glucose intolerance and anaemia are common medical complications observed during pregnancy in Indian women and their effects were studied on the composition of colostrum collected within 24 hours of delivery from lactating women included in the study. PIH during pregnancy significantly decreased colostrum IgA and total proteins, but showed a significant increase in K+ levels, where as women with glucose intolerance showed a significant decrease in total lipids and lactose and an increase in Na+ levels in colostrum compared to normal controls. The group with anaemia also showed a significant decrease in colostrum IgA and total protein levels when compared with the control group. Awareness about the changes that occur in the composition of colostrum during complicated pregnancies can be an important and useful tool for preventive and protective paediatrics.  相似文献   
866.
867.
868.
Serum free fatty acids (FFA) in 100 parturient (50 primiparous and 50 multiparous volunteers) and 50 female patient (30 patients 20–30 years age group and 20 patients 31–50 yrs age group) volunteers undergoing elective major abdominal surgery were monitored during different stages of delivery and surgery respectively. FFA increased in both primiparous and multiparous from full term (46 mg%) to second stage of labour (60 mg%) and gradually decreased to 38 mg% on the third day postpartum. The intergroup comparison between primiparous and multiparous was significant. Surgical stress also increased FFA from the day of admission (21 mg%) to the preoperative stage (35 mg%). The intergroup comparison between 20–30 yrs age group and 31–50 yrs age group did not show any significant change.  相似文献   
869.
Nomographs for determining the filter order of classical filters based on selectivity requirements are presented. The selectivities for a variety of standard classical filters are summarized in equation form and the general selectivity nomograph is constructed. The selectivity equations are then converted into nomograph form by applying the relationship between the transfer function and the response slope. Design examples are presented to demonstrate the usefulness of the selectivity nomographs. These nomographs can be used to gauge filter performance and combined with optimization techniques can yield superior classical filter designs.  相似文献   
870.
A study is made of the orthogonal polynomials on certain curves in the complex plane. Necessary and sufficient conditions for a set of polynomials to be orthogonal on the curves are obtained in terms of symmetric matrices. The relations of the symmetric matrices to Toeplitz matrices and innerwise matrices are shown.  相似文献   
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