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171.
The study determined the types of pesticide/herbicide pollutants in water, sediment and fish from the Kafue River. A preliminary investigation of the oxidative stress from these pesticides/herbicides was also assessed by measurement of catalase activity. Water, sediment and fish samples were collected upstream, midstream and downstream the Kafue river in Chingola, Kitwe, Kafue National Park and Kafue Town. Water, sediment and fish muscle were sampled and analysed for pesticides using Gas chromatography. For catalase activity fish liver samples only were examined. The pesticides/herbicides detected in all samples collectively included: Heptachlor, pp'-DDE, Cypermethrin, Chlordane, Toxaphene, Terbufos, Kelthane, Endosulfan, Dieldrin, pp'-DDD, pp'-DDT, Atrazine, Disulfoton, d-trans-Allethrin and Endrin. On the other hand, catalase activity was detected in all fish liver samples from all sites. Its levels increased significantly from Chingola upstream to sites downstream with highest being in Kafue town. This study therefore, demonstrates that there is widespread contamination of the Kafue River with pesticides/ herbicides. It also demonstrates that organochlorides are found throughout the river especially in fish samples. The spectrum of pesticides/herbicides was much wider in fish probably due to bioaccumulation. It was also observed that fish are subjected to oxidative stress as determined by catalase levels. The stress is more pronounced downstream where the catalase levels were significantly higher than Chingola. The observation that more pesticide varieties are also found downstream may suggest a likely causative effect of the pesticides on oxidative stress although this needs further investigation. This study further tentatively highlights the potential dangers of these agro-related substances to dependants of the Kafue River water body and the need to carry out risk assessments and thereafter institute corrective measures to help reduce contamination and adverse effects.  相似文献   
172.
Results of the present study demonstrated that a specific combination of spawning substrate and water current was indispensable for the spawning of mature Japanese dace, Triborodon hakonensis. It became evident that the environmental factors acted as a trigger for endocrine changes leading to final maturation in this species.  相似文献   
173.
Lesions of articular, sternal and growth plate cartilage in rats   总被引:1,自引:0,他引:1  
Degenerative osteoarthritis was observed in the femur and sternum in specific pathogen free Fisher 344 rats at 13 and 19 months of age. Histological changes consisted of degeneration of the matrix and erosion in the articular cartilage of the femur. In the sternal cartilage, degeneration and necrosis of the matrix, formation of cysts, and cleft-like fractures were observed. In addition, degeneration of the matrix, appearance of eosinophilic streaking, and necrosis and fissure between the growth plate and epiphyseal trabeculae were seen in the femur. The changes in the sternum were essentially the same as the femur.  相似文献   
174.
The optimum feeding rate of the rotifer Bruchionus plicutilis was investigated to determine the best conditions for growth of the rotifer, and also in order to maintain good water quality of the culture. Fifty rotifers of a large size strain were cultured individually at five food density levels of Nannoehloropsis sp. (0.5 ± 106, 1.5 ± 106, 3 ± 106, 5 ± 106, and 8 ± 106 cells/ml). At each level, daily survival and offspring production were recorded until the death of the final individual. The data obtained were analyzed by the life table method. The maximum value of three growth indices (the net reproduction rate, mean life expectancy at age 0, and intrinsic rate of increase) was obtdned at the food density of 1.5 ± 106 cells/ml. The ration size was calculated to be 325% (dry weight)/ day, which is equivalent to about 70% of the saturated feeding rate. It was suggested that the feeding rate should be controlled to lower than the saturated value for an efficient mass culture.  相似文献   
175.
176.
The present study evaluated the effects of infected culture supernatant of erythrocytes, fractionation of culture supernatant and serum from dogs infected with Babesia gibsoni (B. gibsoni) on the maturation of canine reticulocytes in vitro. The SDS-PAGE demonstrated that significantly broader bands were generated by both the infected culture supernatant of erythrocytes and the serum from dogs chronically infected with B. gibsoni. The culture supernatant of erythrocytes infected with B. gibsoni strongly suppressed the maturation of reticulocytes. Prior studies showed that chronically infected serum had inhibitory effects on both the maturation of reticulocytes and the canine pyrimidine 5''-nucleotidase subclass I and purine-specific 5''-nucleotidase activity. In addition, serum free infected culture supernatant of erythrocytes had an inhibitory effect on the morphological maturation of reticulocytes. These results suggest that infected serum and culture supernatant of erythrocytes might accumulate excess proteins and/or metabolites as a result of the inhibited maturation of reticulocytes and decreased activity of erythrocyte 5''-nucleotidase. Furthermore, the fractions observed at >150 kDa- and 150-70 kDa- in the infected culture supernatant and serum retarded the maturation of canine reticulocytes in vitro. The results obtained from the in vitro examinations, in the present study, suggested that B. gibsoni itself and/or its metabolites might release certain proteins in the infected culture supernatant and serum from infected dogs and as a result delay morphological maturation of canine reticulocytes.  相似文献   
177.
In the current study, we describe four novel members of the 90 kDa heat shock protein (HSP90) family expressed in Japanese quail, Coturnix japonica. The coding regions of the genes, CjHSP90AA1, CjHSP90AB1, CjHSP90B1 and CjTRAP1, exhibited more than 94% similarity to their related genes in chicken. The putative proteins encoded by these quail genes contained motifs considered essential for HSP90 gene function. In addition, the predicted proteins were more similar to HSP90AA1, HSP90AB1, HSP90B1 and TRAP1 proteins expressed in vertebrates than they were to other members of the HSP90 family. Exon numbers of CjHSP90AA1 (11), CjHSP90AB1 (12) or CjTRAP1 (18) are the same as the chicken and mammalian orthologs. Furthermore, gene order in the regions surrounding CjHSP90AB1 and CjTRAP1 has been preserved, providing evidence that the genomic regions were orthologous to HSP90‐containing regions in the chicken genome. The promoter regions of the genes also contained conserved motifs identified in related genes of chicken. However, the nucleotide sequences of the 5′‐flanking region of these genes were highly polymorphic. We also found that CjHSP90AA1 exhibited a robust response to heat shock treatment. Taken together, the data suggest that CjHSP90AA1, CjHSP90AB1, CjHSP90B1 and CjTRAP1 encode orthologs of HSP90AA1, HSP90AB1, HSP90B1 and TRAP1, respectively.  相似文献   
178.
179.
A 9-year, 7-month-old female German shepherd weighing 26.6 kg was admitted to the hospital for pica and diarrhea. A large mass was found in the right ovary and removed, and cross section of the mass revealed a multilobular tumor consisting of several cystic cavities which contained tufts of dark hair in thick creamy-white sebaceous fluid. Histologically, the tumor consisted of adipose tissue, central nervous tissue, crystalline lens, cartilage and bone. In the central nervous tissue, lens and lesions like nonsuppurative inflammation comprizing of accumulation of glial cells and lymphocytic perivascular cuffing were observed. The tumor was diagnosed as a mature cystic teratoma.  相似文献   
180.
The inhibitory effects of 45 plant extracts selected from Central Kalimantan, Indonesia on Babesia gibsoni in vitro and their acute toxicity to mice were evaluated. Of these plant extracts studied, Arcangelisia flava, Curcuma zedoaria, Garcinia benthamiana, Lansium domesticum and Peronema canescens were found to have appreciable antibabesial activity with IC50 values from 5.3 to 49.3 microg/ml without acute toxicity in mice at the intraperitoneal dose of 0.7 g/kg of body weight.  相似文献   
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