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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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3.
A fluidized bed biofilm reactor using sand as the carrier particle was employed to study the effects of superficial velocity on the removal of nitrates as well as on the growth of the biofilm. Velocity was found to affect significantly both nitrate removal and biofilm growth. An analysis based on heterogenous catalysis was used to describe the denitrification process. There is good agreement between analysis and experimental measurements for startup and steady-state operating conditions. 相似文献
4.
Nine human infections due toT. simii comprising of tinea corporis (6), tinea cruris (2) and tinea capitis (1) have been reported. Human cases were having lesions typically of zoophilic contracted infections. Lesions in dogs were on nose and upper lip and were circular. All the strains showed typical and identical macro and microscopie morphology. Three isolates studied by Stockdale were negative (2) and positive (1) strains. One studied here was negative. Possible epidemiology is discussed. 相似文献
5.
M. Kaur K. Joshi N. K. Ganguly R. C. Mahajan N. Malla 《International journal for parasitology》1995,25(12):1443-1450
Cysticercosis, a disease of economic and public health importance, is caused by Cysticercus cellulosae, the metacestode stage of Taenia solium. Experimental induction of cysticercosis was achieved in young pigs by feeding an optimum dose of 20,000 T. solium (Indian strain) eggs after immunosuppression, to assess the effect of albendazole and development of the immune response to cysticercus antigens before and after treatment.
Histopathological studies revealed the presence of cysticerci in liver, lungs and muscles. Treatment with albendazole at 15 mg kg−1 body weight daily for 30 days starting from day 0 or 15 days post-infection resulted in 100% cure rates. Increases in antibody titre to crude soluble extract and a Sephadex G-200 purified antigenic fraction of Cysticercus cellulosae were found on days 25, 40 and 55 post-infection in untreated pigs and those in which treatment started on day 15 post-infection, whereas no increase in antibody response was observed in pigs in which treatment started on day 0. 相似文献
6.
Post-transfusion malaria in thalassaemia patients 总被引:1,自引:0,他引:1
A total of 125 beta-thalassaemia patients receiving repeated blood transfusions were screened by Giemsa stain, Acridine-orange stain and antigen detection for evidence of malaria infection on each visit. A total of 8 (6.4%) of the patients developed post-transfusion malaria (PMT) as confirmed by tracing the infected blood donors. A high incidence of PTM in thalassaemia patients appears to be due to the use of fresh blood and the high frequency of blood transfusions required by these patients. Antigen detection using monoclonal antibody was found to be more sensitive for diagnosis of PTM and for screening suspected donors than the conventional blood smear examination methods and is therefore recommended for routine blood donor screening to rule out malaria infection. 相似文献
7.
Vijay K. Mahajan Dominic M. Desiderio 《Biochemical and biophysical research communications》1978,82(4):1104-1110
The amino acid sequence of oligopeptides can be determined from the mass spectra of their volatile derivatives. New peptide derivatives are described which are prepared from permethylated peptides by reduction with borane-tetrahydrofuran. These derivatives have been found to be more volatile than the corresponding permethylated ones. The procedure is illustrated by application of this technique to representative oligopeptides. As little as 10–100 nmol of these peptides have been sequenced using this technique. 相似文献
8.
14C-17-Hydroxyprogesterone was incubated with 7000 × g × 20 min supernatants of rat testis homogenates in the presence of various concentrations of 3H-progesterone, both under conditions where metabolism would take place and where it would be prevented. When metabolism was prevented, the ratio of progesterone to 17-hydroxyprogesterone in the microsomal fraction was 3 times that which was added to the incubation medium.Progesterone competitively inhibited 17,20-lyase action on added 17-hydroxyprogesterone but not on 17-hydroxyprogesterone formed from the added progesterone. The rate of formation of 17-hydroxyprogesterone from progesterone, however, was inhibited by added 17-hydroxyprogesterone. The results indicate that there is no free exchange of an intermediate between progesterone and androstenedione with the soluble fraction, either inside or outside the microsomal vesicle. The limited exchange with 17-hydroxyprogesterone in solution probably represents exchange with an enzyme-bound intermediate. 相似文献
9.
Iris M Costa Tallybia HT Nasser Marilene Demasi Rafaella MP Nascimento Luis ES Netto Sayuri Miyamoto Fernanda M Prado Gisele Monteiro 《BMC microbiology》2011,11(1):268
Background
The gene YCL047C, which has been renamed promoter of filamentation gene (POF1), has recently been described as a cell component involved in yeast filamentous growth. The objective of this work is to understand the molecular and biological function of this gene.Results
Here, we report that the protein encoded by the POF1 gene, Pof1p, is an ATPase that may be part of the Saccharomyces cerevisiae protein quality control pathway. According to the results, Δpof1 cells showed increased sensitivity to hydrogen peroxide, tert-butyl hydroperoxide, heat shock and protein unfolding agents, such as dithiothreitol and tunicamycin. Besides, the overexpression of POF1 suppressed the sensitivity of Δpct1, a strain that lacks a gene that encodes a phosphocholine cytidylyltransferase, to heat shock. In vitro analysis showed, however, that the purified Pof1p enzyme had no cytidylyltransferase activity but does have ATPase activity, with catalytic efficiency comparable to other ATPases involved in endoplasmic reticulum-associated degradation of proteins (ERAD). Supporting these findings, co-immunoprecipitation experiments showed a physical interaction between Pof1p and Ubc7p (an ubiquitin conjugating enzyme) in vivo.Conclusions
Taken together, the results strongly suggest that the biological function of Pof1p is related to the regulation of protein degradation.10.