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1.
Comparative tissue ascorbic acid studies in fishes   总被引:1,自引:0,他引:1  
Comparative tissue ascorbic acid levels in four species of major carp viz., Labeo rohila, L. calbasu, Cirrhina tnrigala and Catla catla , were investigated. The ascorbic acid level was found to be the highest in the spleen in the four species studied (range 430–380 μg/g) followed by the anterior (adrenal) kidney, gonads, liver, renal kidney, brain and/or eye. Heart and blood had the lowest levels (range 26–18 μg/ml) amongst the tissues studied. Overall tissue ascorbic acid levels were the highest in L. rohita and the lowest in C. mrigala . Investigation on seasonal variations in blood and kidney ascorbic acid levels of Notopterus notopterus revealed peak levels in spring (February-April) and the lowest levels in the postspawning period (August-September).  相似文献   
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Thermal injury triggers a fulminant inflammatory cascade that heralds shock, end-organ failure, and ultimately sepsis and death. Emerging evidence points to a critical role for the innate immune system, and several studies had documented concurrent impairment in neutrophil chemotaxis with these post-burn inflammatory changes. While a few studies suggest that a link between neutrophil motility and patient mortality might exist, so far, cumbersome assays have prohibited exploration of the prognostic and diagnostic significance of chemotaxis after burn injury. To address this need, we developed a microfluidic device that is simple to operate and allows for precise and robust measurements of chemotaxis speed and persistence characteristics at single-cell resolution. Using this assay, we established a reference set of migration speed values for neutrophils from healthy subjects. Comparisons with samples from burn patients revealed impaired directional migration speed starting as early as 24 hours after burn injury, reaching a minimum at 72–120 hours, correlated to the size of the burn injury and potentially serving as an early indicator for concurrent infections. Further characterization of neutrophil chemotaxis using this new assay may have important diagnostic implications not only for burn patients but also for patients afflicted by other diseases that compromise neutrophil functions.  相似文献   
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Heteromazocraes mamaevi n. sp. is described from a cyprinid, Securicula gora (Ham.) from the Lucknow district, India. It is characterised by well-developed cephalic glands, the shape of the genital spines, the structure of the egg and the shape of the clamp sclerites. This is the first record of the genus Heteromazocraes Mamaev, 1981 from a cyprinid fish.  相似文献   
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The distribution of delta 5-3 beta-HSD, peroxidase and cytochrome oxidase in immature, sexually mature and pregnant rabbit ovary has been studied histochemically. Corpora lutea are found only in pregnant rabbits. delta 5-3 beta-HSD is present in the theca interna of mature follicles, corpora lutea and interstitial gland cells but is absent in the granulosa cells of both developing and mature follicles. The granulosa cells of mature and developing follicles, hypertrophied theca interna and the luteal cells all show intense cytochrome oxidase activity. Peroxidase is present in the corpora lutea only. It is suggested that delta 5-3 beta-HSD in the theca interna and interstitial gland cells is the enzyme responsible for steroid synthesis in the ovaries of immature as well as sexually mature rabbits, while peroxidase and delta 5-3 beta-HSD present in the corpora lutea together regulate luteal steroidogenesis during pregnancy. The intense cytochrome oxidase activity together with peroxidase and delta 5-3 beta-HSD confirms the observations that this tissue is a site of intense oxidative activity.  相似文献   
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A number of methods of construction of partially balanced incomplete block designs with nested rows and columns are developed and new balanced incomplete block designs with nested rows and columns are obtained as a by-product.  相似文献   
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Increased therapeutic efficacy of zidovudine in combination with vitamin E   总被引:2,自引:0,他引:2  
Antiviral activity and bone marrow toxicity of 3'-azido-3'deoxythymidine (Zidovudine; AZT) was evaluated in the presence of alpha-D-tocopherol acid succinate (ATS) in the MT4 cell line and in murine hematopoietic progenitor cells, respectively. At varying concentrations (.016 to .125 microM) of AZT, addition of ATS (5 to 15 micrograms/ml) showed a dose-dependent increase in anti-HIV activity. The ED90 of AZT in this test system was 0.37 microM, whereas in the presence of ATS (15 micrograms/ml) it was 0.06 microM, thus producing an approximately 6-fold increase in anti-HIV activity. In contrast, in murine bone marrow cells, ATS (4 micrograms/ml) showed significant protection (p less than 0.05) against AZT-induced toxicity as measured by CFU-E and CFU-GM assays. The IC50 values in the presence and absence of ATS for CFU-E were 3.7 and 1.5 microM, whereas for CFU-GM were 6.0 and 2.7 microM, respectively. Overall, these data suggest that AZT in combination with ATS has greater therapeutic efficacy against HIV-1.  相似文献   
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A gentle method for the isolation of nuclei from developing silk glands ofBombyx mori has been standardized. The nuclei, whether isolated or directly visualizedin situ within the silk glands, exhibit complex morphology. The nuclei occupy almost the entire volume of the gigantic silk gland cells. Although the isolated nuclei still retain their ramified morphology, being polyploid they are fragile and often become fragmented. The histone and low-salt-extractable proteins from nuclei isolated from the middle and posterior silk glands on different days of the fourth and fifth instars of larval development have been analysed. The histones did not show any stage- or tissue-specific variations whereas the low-salt-extractable proteins showed some developmental stage specific variation. Using the antibody raised against one such protein, its absence in the early stage of development has been confirmed by Western blotting techniques. This developmental stage specific protein may be functionally linked to some activities responsible for boosting up the production of silk or silk-related proteins during the fifth instar of larval development.  相似文献   
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