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51.
Jeonghwan Park Harry V. Daniels Sung Hwoan Cho 《Journal of the World Aquaculture Society》2013,44(5):726-734
This study was performed to estimate the nitrite toxicity to southern flounder, Paralichthys lethostigma, in brackish water (7.5 ppt of salinity). For a LC50 test, 20 fingerlings (5.7 ± 0.4 cm) in each aquarium (15 L) were exposed to the concentrations of 0, 1, 5, 10, 15, 30, 60, 120, and 240 mg NO2?‐N/L in duplication for 10 d. Median lethal concentration at 96 h (96‐h LC50) was calculated as 81.6 mg NO2?‐N/L. For a verification test, young flounder (164.2 ± 9.1 g) were exposed to a simulated culture condition in recirculating systems (1000 L). Sodium nitrite was not added to control system, whereas it was added to Treatment system 1 (TS 1) and Treatment system 2 (TS 2) to maintain nitrite concentrations of 20 and 30 mg NO2?‐N/L, respectively. The plasma nitrite concentrations of the young flounder in TS 1 and TS 2 were 4.5 and 6.6 mg NO2?‐N/L, respectively, after 2 wk. At this time, the methemoglobin percentages in TS 1 and TS 2 reached 85.8 and 89.7%, and survival rates were 37.5 and 25.0%, respectively. The results of these tests indicate that southern flounder do not concentrate nitrite in blood from the environment, but they seem to be more sensitive to nitrite compared with other species that do not concentrate nitrite. 相似文献
52.
53.
D. U. Han C. Choi J. Kim W.‐S. Cho H.‐K. Chung S.‐K. Ha K. Jung C. Chae 《Zoonoses and public health》2002,49(7):346-348
The in vitro susceptibilities of 128 isolates of east1+Escherichia coli from pre‐weaned and post‐weaned pigs with diarrhoea were tested with nine commonly used anti‐microbial agents by an agar dilution minimal inhibitory concentration (MIC) procedure according to National Committee for Clinical Laboratory Standards guidelines. For the isolates from pre‐weaned and post‐weaned pigs, most of them were susceptible to low concentrations (MIC90) of tetracycline (4 and 2 μg/ml), ceftiofur (2 and 2 μg/ml), and colistin (4 and 2 μg/ml). Marked resistance was found in others. 相似文献
54.
Formation of a Reservoir of Sperm in the Oviduct 总被引:2,自引:0,他引:2
SS Suarez 《Reproduction in domestic animals》2002,37(3):140-143
A reservoir of sperm in the initial segment of the oviduct has been found in several species of domestic and laboratory mammals. Evidently, the reservoir serves to ensure successful fertilization by providing the appropriate number of sperm in the appropriate physiological state for fertilizing oocytes soon after they enter the oviduct. Recent evidence indicates that sperm are trapped in the reservoir by binding to specific carbohydrate moieties on the surface of the mucosal epithelium of the oviduct. A bovine seminal plasma protein has been identified that associates with sperm and confers on them the capacity to bind to the carbohydrate moiety. 相似文献
55.
56.
Frederick J. Muehlbauer Seungho Cho Ashutosh Sarker Kevin E. McPhee Clarice J. Coyne P. N. Rajesh Rebecca Ford 《Euphytica》2006,147(1-2):149-165
Summary Lentil is a self-pollinating diploid (2n = 14 chromosomes) annual cool season legume crop that is produced throughout the world and is highly valued as a high protein
food. Several abiotic stresses are important to lentil yields world wide and include drought, heat, salt susceptibility and
iron deficiency. The biotic stresses are numerous and include: susceptibility to Ascochyta blight, caused by Ascochyta lentis; Anthracnose, caused by
Colletotrichum truncatum; Fusarium wilt, caused by
Fusarium oxysporum; Sclerotinia white mold, caused by
Sclerotinia sclerotiorum; rust, caused by
Uromyces fabae; and numerous aphid transmitted viruses. Lentil is also highly susceptible to several species of
Orabanche prevalent in the Mediterranean region, for which there does not appear to be much resistance in the germplasm. Plant breeders
and geneticists have addressed these stresses by identifying resistant/tolerant germplasm, determining the genetics involved
and the genetic map positions of the resistant genes. To this end progress has been made in mapping the lentil genome and
several genetic maps are available that eventually will lead to the development of a consensus map for lentil. Marker density
has been limited in the published genetic maps and there is a distinct lack of co-dominant markers that would facilitate comparisons
of the available genetic maps and efficient identification of markers closely linked to genes of interest. Molecular breeding
of lentil for disease resistance genes using marker assisted selection, particularly for resistance to Ascochyta blight and
Anthracnose, is underway in Australia and Canada and promising results have been obtained. Comparative genomics and synteny
analyses with closely related legumes promises to further advance the knowledge of the lentil genome and provide lentil breeders
with additional genes and selectable markers for use in marker assisted selection. Genomic tools such as macro and micro arrays,
reverse genetics and genetic transformation are emerging technologies that may eventually be available for use in lentil crop
improvement. 相似文献
57.
We investigated the effects of erythritol on rats with streptozotocin- (STZ-) induced diabetes mellitus. Oral administration of erythritol [100, 200, or 400 mg (kg body weight)(-1) day(-1) for 10 days] to rats with STZ-induced diabetes resulted in significant decreases in the glucose levels of serum, liver, and kidney. Erythritol also reduced the elevated serum 5-hydroxymethylfurfural level that is glycosylated with protein as an indicator of oxidative stress. In addition, thiobarbituric acid-reactive substance levels of serum and liver and kidney mitochondria were dose-dependently lower in the erythritol-treated groups than in the control diabetic group. Furthermore, the serum creatinine level was reduced by oral administration of erythritol in a dose-dependent manner. These results suggest that erythritol affects glucose metabolism and reduces lipid peroxidation, thereby improving the damage caused by oxidative stress involved in the pathogenesis of diabetes. 相似文献
58.
5-(2,6-difluorobenzyl)oxymethyl-5-methyl-3-(3-methylthiophen-2-yl)- 1,2-isoxazoline as a useful rice herbicide 总被引:1,自引:0,他引:1
Hwang IT Kim HR Jeon DJ Hong KS Song JH Cho KY 《Journal of agricultural and food chemistry》2005,53(22):8639-8643
5-(2,6-difluorobenzyl)oxymethyl-5-methyl-3-(3-methylthiophen-2-yl)-1,2-isoxazoline derivative was synthesized, and its herbicidal activity was assessed under glasshouse and flooded paddy conditions. 5-(2,6-Difluorobenzyl)oxymethyl-5-methyl-3-(3-methylthiophen-2-yl)-1,2-isoxazoline demonstrated good rice selectivity and potent herbicidal activity against annual weeds at 125 g of a.i. ha(-1) under greenhouse conditions. Soil application of this compound showed complete control of barnyard-grass to the fourth leaf stage at 250 g of a.i. ha(-1). Field trials indicated that this compound controlled annual weeds rapidly with a good tolerance on transplanted rice seedlings by post-emergence and soil application. This compound showed a low mammalian and environmental toxicity in various toxicological tests. 相似文献
59.
Kim BT Min YK Asami T Park NK Kwon OY Cho KY Yoshida S 《Journal of agricultural and food chemistry》1999,47(1):313-317
Fluorine was introduced into the 2-position of the side chain of abscisic acid (ABA) analogues by Wittig reaction of alpha-ionone derivatives with ethyl triethylphosphono-2-fluoroacetate. The effects of the fluorinated analogues were evaluated on inhibition of cress seed germination and inhibition of gibberellin-inducible alpha-amylase induction in embryoless barley half-seeds. (2E, 4E)-2-Fluoro-5-(1'-hydroxy-2',6', 6'-trimethyl-2'-cyclohexen-1'-yl)-3-methyl-2,4-pentadienoic acid (5b) showed potent inhibitory activity at the same level as ABA in the cress seed germination test, and 5b also inhibited gibberellin-inducible alpha-amylase induction at 4 x 10(-)(6), 3 times the concentration of ABA (1 x 10(-)(6)) for 50% inhibition of alpha-amylase production. 5b also showed dehydrin induction activity. These results indicate that fluorinated ABA analogues mimic ABA action and can be a lead for a plant growth regulator which regulates plant growth or protects plants from environmental stresses. 相似文献
60.
To determine whether green tea polyphenol ameliorates the pathological conditions induced by excessive dietary arginine, green tea polyphenol was administered to rats at a daily dose of 50 or 100 mg/kg body weight for 30 days with a 2% w/w arginine diet. In arginine-fed control rats, urinary and/or serum levels of guanidino compounds, nitric oxide (NO), urea, protein, and glucose increased significantly, while the renal activities of the oxygen species-scavenging enzymes superoxide dismutase (SOD) and catalase decreased, compared with casein-fed rats. However, rats given green tea polyphenol showed significant and dose-dependent decreases in serum levels of creatinine (Cr) and urea nitrogen and urinary excretion of Cr, and they exerted a slight reduction of nitrite plus nitrate, indicating that green tea polyphenol reduced the production of uremic toxins and NO. In addition, in arginine-fed rats the urinary urea, protein, and glucose level increases were reversed by the administration of green tea polyphenol. Moreover, in rats given green tea polyphenol the SOD and catalase activities suppressed by excessive arginine administration increased dose-dependently, implying the biological defense system was augmented as a result of free radical scavenging. These results suggest that green tea polyphenol would ameliorate renal failure induced by excessive dietary arginine by decreasing uremic toxin, and NO production and increasing radical-scavenging enzyme activity. 相似文献