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801.
S K Raha S K Dey S K Roy S Chaudhuri S L Chakrabarty 《Biochemistry international》1990,21(6):1001-1011
L-Asparaginase from Cylindrocarpon obtusisporum MB-10 inhibits the growth of Ascites Fibrosarcoma and Dalton's Lymphoma tumor cells in vivo and significantly increases the survival rate of tumor bearing mice. The enzyme-treated normal mice become more healthy and survive longer than their usual life span. The spleen size of normal animals treated with L-asparaginase become larger, and the number of their rosetting T-lymphocytes along with the capacity of SRBC constellation gets increased. The surface topography of splenic T-lymphocytes of enzyme-treated mice exhibits some extensions of different parts of the membrane with ruffling of surface and formation of innumerable blebs, foldings, microvilli, etc. The adherence of leukocytes of peritoneal exudate cells of these mice is also enhanced. All results suggest that C. obtusisporum MB-10 L-asparaginase is active against tumors and non-immunosuppressive, and it deserves to be an immunotherapeutic agent. 相似文献
802.
Exacerbations are a major cause of morbidity in asthma and generate high health costs. Identification and management of adults with asthma who are prone to exacerbations is of considerable importance as by this means it should be possible to reduce the number of patients who currently experience inadequately controlled disease. Exacerbations occur most frequently in individuals with severe disease. Other risk factors include a history of a recent exacerbation, co-morbidities such as a raised body mass index and psychological problems as well as current smoking and lower socio-economic status. A low FEV1, particularly if combined with the additional information from questionnaires helps predict exacerbations. Despite the association between these risk factors and exacerbations it remains difficult to accurately predict in an individual patient with asthma whether they will go on to develop an exacerbation in the future. A major aim of international guidelines on the management of asthma is to prevent future risks of exacerbations, but some patients, particularly those with severe disease, respond poorly to current therapies and continue to experience recurrent exacerbations. There is an unmet need for improved management strategies and drugs targeted at preventing asthma exacerbations. Monitoring induced sputum eosinophil cell counts is helpful in preventing exacerbations in some patient with severe asthma. Future developments are likely to include the identification of better biomarkers to predict exacerbations or the cause of exacerbations, augmentation of the immunological response to viruses at the time of the exacerbation, the use of telemonitoring in patients with severe asthma and the development of improved therapies targeted at reducing exacerbations. 相似文献
803.
K Pahan R Gachhui S Ray J Chaudhuri A Mandal 《Indian journal of experimental biology》1991,29(12):1147-1149
A broad-spectrum Hg-resistant strain of B. pasteurii DR2 utilized phenylmercuric acetate (PMA) as sole source of carbon. This bacterial strain contained a constitutive organomercurial lyase which specifically degraded PMA but not other organo-mercurials. This PMA-lyase activity was also stimulated to different extents when this bacterial strain was grown in presence of different organic compounds as sole source of carbon. 相似文献
804.
805.
A new neolignan designated (?)-maglifloenone and the known one futoenone, both of which contain the rarely occurring spirocyclohexadienone skeleton, have been isolated together with the tetrahydrofuranolignan (+)-veraguensin, an optically inactive tertiary base taspine and β-sitosterol from the leaves and twigs of Magnolia liliflora. The structure and stereochemistry of (?)-maglifloenone have been deduced from the spectral data and the mass fragmentation of (?)-maglifloenone and futoenone have been rationalized. This is the first report of two neolignans of spirocyclohexadienone skeleton and of taspine from the Magnoliaceae family and the second report of the natural occurrence of futoenone. 相似文献