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931.
盐酸环丙沙星在雏鸡体内蓄积毒性的研究 总被引:1,自引:0,他引:1
对盐酸环丙沙星在雏鸡体内的急性毒性进行了研究。结果LD50为2862.86mg/kg体重;蓄积系数K≥5.3,此时无一只雏鸡死亡,为轻度蓄积或基本无蓄积;雏鸡对本品产生明显耐受性,应用安全可靠。 相似文献
932.
933.
Genotypic Difference in Plant Growth and Mineral Composition in Barley Under Aluminum Stress 总被引:2,自引:0,他引:2
Four barley genotypes (Tiantaiyangdamai, Xiyin2, Mimai114 and Tai94-Ce6) were exposed to0, 50, 100, and 150 μM of Al-containing solution with pH 4.5, to determine the differences in growth inhibi-tion, Al concentration and accumulation and mineral composition among genotypes. The results showed thatMimai114 and Tai94-Ce6 had significantly higher Al concentration and accumulation than Tiantaiyangdamiand Xiyin2, especially in roots, and the growth traits including root and shoot dry weights, shoot height, rootlength and tillers per plant were more inhibited in the former two genotypes. Al treatments caused a significantreduction of N, P, K, Ca, Mg and Mn content in both roots and shoots, of Cu in shoots ; and a significant increase in Fe and Zn content in both roots and shoots, of Cu in roots. The changed rates of mineral contentcaused by Al treatments, in terms of the content in 150 μM Al divided by the content in the control, differedsignificantly among four genotypes. Two Al-sensitive genotypes, Mimai114 and Tai94-Ce6 had much greater changesin mineral content than other two Al-tolerant genotypes Tiantaiyangdamai and Xiyin2 when subjected to Al stress incomparison with the control. It is indicated that the Al-tolerant genotype is characterized by less uptake and accumula-tion of Al in roots and smaller disorders in mineral metabolism and ion homeostasis. 相似文献
934.
K. A. Skorupski A. C. Durham L. Duda K. U. Sørenmo 《Veterinary and comparative oncology》2008,6(2):120-125
Small to intermediate cell alimentary lymphoma was diagnosed in a cat after abdominal exploratory surgery with no prior history of pulmonary disease. Initial response to several chemotherapy regimens was poor, but a long‐term remission was achieved with CCNU (lomustine) and corticosteroid therapy. After receiving a total cumulative CCNU dose of 552 mg m?2 over 12 months, an acute episode of respiratory distress occurred and the cat died. Necropsy identified severe diffuse pulmonary fibrosis and no signs of lymphoma. This is the first report of pulmonary fibrosis following high cumulative dose nitrosourea chemotherapy in a cat. 相似文献
935.
Thirteen dogs with previously untreated multicentric lymphoma were enrolled in a prospective study investigating the effects of low‐dose rate total body irradiation (TBI) and chemotherapy. Dogs received either 6 or 8 Gy TBI in half‐body fractions, 2 weeks apart. Toxicity consisted of mild to moderate haematological and gastrointestinal (GI) signs. One dog died from treatment complications. Anorexia was noted independent of dose. Haematological toxicity was more common and more severe after 8 Gy treatment. GI toxicity was more likely postcaudal half‐body irradiation with 8 Gy. Other than leukotrichia, late effects from radiation were not observed. Results indicated that haematological and nonhaematological toxicity was dose dependent. However, the protocol was well tolerated and treatment intensification using a 2‐week inter‐radiation interval was possible in all dogs treated with 6 Gy. Preliminary survival data for these dogs were very encouraging, providing a strong rationale to analyse the efficacy of low‐dose rate irradiation (LDRI) in canine lymphoma. 相似文献
936.
Min-Won Baek Seung-Hyeok Seok Hui-Young Lee Dong Jae Kim Byoung-Hee Lee Young-Tae Ahn Kwang-Sei Lim Chul-Sung Huh Jae-Hak Park 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(1):31-37
An herbal extract mixture and yogurt added to the herbal extract mixture were tested for their protective and therapeutic effects on ethanol-induced liver injury. The herbal extract mixture, yogurt and commercial drugs were used for treatment for two weeks prior to administering a single oral dose of ethanol (3 g/kg body weight). The herbal extract mixture and yogurt added to the herbal extract mixture were found to provide protection against ethanol-induced toxicity comparable to the commercial drug treatment, according to the serum and histopathological analysis. It was also shown that co-treatment with herbal extract mixture and yogurt against a triple oral dose of ethanol (2 g/kg body weight, over one week) provided protection against ethanol toxicity. After the initial set of experiments, the herbal extract mixture and yogurt treatments were extended for three more weeks. When compared to the positive control, further treatment with both the herbal extract and yogurt significantly reduced liver injury and resulted in a lower grade of lipid deposition. 相似文献
937.
Sung‐Eun Lee Byoung‐Ho Lee Won‐Sik Choi Byeoung‐Soo Park Jeong‐Gyu Kim Bruce C Campbell 《Pest management science》2001,57(6):548-553
The fumigant toxicity of various volatile constituents of essential oils extracted from sixteen Korean spices and medicinal plants towards the rice weevil, Sitophilus oryzae L (Coleoptera: Curculionidae), was determined. The most potent toxicity was found in the essential oil from Mentha arvensis L var piperascens (LC50 = 45.5 µl litre?1 air). GC–MS analysis of essential oil from M arvensis showed it to be rich in menthol (63.2%), menthone (13.1%) and limonene (1.5%), followed in abundance by β‐pinene (0.7%), α‐pinene (0.6%) and linalool (0.2%). Treatment of S oryzae with each of these terpenes showed menthone to be most active (LC50 = 12.7 µl litre?1 air) followed by linalool (LC50 = 39.2 µl litre?1 air) and α‐pinene (LC50 = 54.9 µl litre?1 air). Studies on inhibition of acetylcholinesterase activity of S oryzae showed menthone to have a nine‐fold lower inhibitory effect than menthol, despite menthone being 8.1‐fold more toxic than menthol to the rice weevil. Different modes of toxicity of these monoterpenes towards S oryzae are discussed. © 2001 Society of Chemical Industry 相似文献
938.
13种杀虫剂对龟纹瓢虫及大草蛉的毒力研究 总被引:8,自引:0,他引:8
本实验采用玻瓶药膜法,测定了6种杀虫单剂及7种杀虫混剂对龟纹瓢虫及大草蛉成虫的室内毒力。结果表明:6种单剂对龟纹瓢虫及大草蛉的毒力顺序完全一致,即高效氯氟氰菊酯>灭多威>辛硫磷>甲基对硫磷>甲胺磷>硫丹;7种混剂对龟纹瓢虫及大草蛉的毒力顺序有所差别,但其中均以甲胺磷+硫丹表现最为完全,而以灭多威+甲基对硫磷表现毒力最高;联合毒力以甲基对硫磷+辛硫磷、高效氯氟氰菊酯+辛硫磷对2种天敌一致表现为拮抗,甲胺磷+硫丹、灭多威+甲基对硫磷、高效氯氟氰菊酯+硫丹一致表现为增毒。 相似文献
939.
Seven lambs were fed a mixture of bog plants containing 15 g (wet matter)Narthecium ossifragum per kg live weight for 10 consecutive days. Their serum creatinine concentration increased from day 1 to 4 but then fell to normal by day 6 after feeding started. In the same animals, the serum magnesium concentration was increased on days 3, 4 and 5. Histopathological examination of the kidneys of 2 lambs killed after being fed 25 gN. ossifragum per kg live weight for one day revealed tubular epithelial cell degeneration and necrosis. There were no signs of disease or distress in the experimental animals and their appetite remained normal throughout the experimental period. It was concluded thatN. ossifragum is probably nephrotoxic to lambs.Abbreviations ALP
alkaline phosphatase
- ASAT
aspartate aminotransferase
- -HBA
-hydroxybutyric acid
- CK
creatine kinase
- d.m.
dry matter
- -GT
-glutamyltransferase
- GLDH
glutamate dehydrogenase
- MCV
mean cell volume
- RBC
red blood cells
- SEM
standard error of the mean
- WBC
white blood cells
- w.m.
wet matter 相似文献
940.
I. Gapillout M. -L. Milat J. -P. Blein 《European journal of plant pathology / European Foundation for Plant Pathology》1996,102(2):127-132
Cell suspension cultures were set up from two tomato cultivars, one resistant, (Rio grande) and one susceptible (63.5) toFusarium oxysporum f. sp.lycopersici. Growth rates of the two cell cultures were comparable. Toxicity of fusaric acid, expressed as the fresh weight loss, was analyzed: It was significant in both cases after 10 h, but toxicity was twice as high for 63.5 suspension cells. In the same way, electrolyte leakage caused by fusaric acid was three times more important for 63.5 suspension cells. Moreover, fusaric acid treatment resulted in an acidification of the extracellular medium for 63.5 suspension cells (0.4 pH unit), whereas an alkalization was observed for Rio grande suspension cells (0.2 pH unit). Preliminary experiments suggest that fusaric acid was partially metabolized by Rio grande suspension cells, however, no detoxified forms of fusaric acid were detected either in cells or in culture filtrates. For these two tomato cultivars, the differences in sensitivity to fusaric acid of cultivated cells correspond to the differences in plant susceptibility toFusarium oxysporum f. sp.lycopersici.Abbreviations BAP
6-benzylaminopurine
-
conductivity
- 2,4-D
2,4-dichlorophenoxyacetic acid
- EtOAc
ethyl acetate
- FA
fusaric acid
-
resistivity 相似文献