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101.
K.W. Peng S.F. Chew C.B. Lim S.S.L. Kuah W.K. Kok Y.K. Ip 《Fish physiology and biochemistry》1998,19(1):59-69
A lipase was purified from the extract of the delipidated powder of red sea bream hepatopancreas to nar homogeneity by fractional precipitation with ammonium sulfate and sequential chromatography on first anion-exchange-, hydrophobic- and second anion-exchange columns followed by gel filtration and anion-exchange HPLC. The final enzyme preparation showed a single band with an apparent molecular mass of approx. 64 kDa by sodium dodecyl sulfate-polyacrylamid e gel electrophoresis. The purified enzyme had a pH optimum in the range of pH 7.0–9.0. Using -nitrophenyl myristate or triolein as a substrate, the enzyme required the presence of sodium taurocholate or sodium cholate for its activity. No activity was observed in the presence of sodium deoxycholate. The enzyme preferentially hydrolyzed ethyl esters of polyunsaturated fatty acid, such as arachidonic acid and eicosapentaenoic acid which were resistant to porcine pancreatic lipase. These results strongly suggest that the enzyme purified from the hepatopancreas of red sea bream is homologous to mammalian bile salt-activated lipase. 相似文献
102.
Lipoxygenase (LOX)-inhibiting compounds from the leaves of Chisocheton polyandrus Merr. were isolated in this study using a bioactivity-guided fractionation technique. Two dammarane triterpenoids, dammara-20,24-dien-3-one (1) (IC(50)=0.69±0.07 μM) and 24-hydroxydammara-20,25-dien-3-one (2) (IC(50)=1.11±0.38 μM), were isolated and identified based on the soybean LOX assay. Dammara-20,24-dien-3-one (1) exhibited dual inhibition of both human 5-LOX (IC(50)=24.27±2.92 μM) and cyclooxygenase-2 (COX-2) (IC(50)=3.17±0.90 μM), whereas 24-hydroxydammara-20,25-dien-3-one (2) did not exhibit any significant inhibitory effects. This report is the first to detail the inhibition of LOX and COX by both C. polyandrus and its isolated compounds. 相似文献
103.
Ying Liu Yuntao Guan Nora Feng Yee Tam Tadao Mizuno Hiroshi Tsuno Wanpeng Zhu 《Water, air, and soil pollution》2010,209(1-4):333-343
Occurrence and distribution of three typical endocrine-disrupting chemicals (EDCs), nonylphenol mixture (NPs), bisphenol A (BPA), and 17α-ethynilestradiol (EE2), were investigated in the seawater, suspended solid, and sediment around the coastline of Shenzhen city. Field surveys were conducted in both dry season and rainy season to access the influence of rainfall and basic water quality parameters on the distribution of target EDCs. In the seawater, NPs, BPA, and EE2 ranged from 31 to 1,777 ng/l, from 11 to 777 ng/l, and from 10 to 269 ng/l, respectively. In the suspended solid, NPs, BPA, and EE2 were in the range from 3 to 289 ng/l, from 1 to 75 ng/l, and from 1 to 29 ng/l, respectively. In the sediment, NPs, BPA, and EE2 varied from 9 to 355 ng/g dry weight (dw), from 3 to 156 ng/g dw, and from 7 to 144 ng/g dw, respectively. With the increasing rainfall, the concentrations of target EDCs decreased in seawater and sediment and increased in suspended solid at all the sampling locations. Among the six measured basic water quality parameters, the volatile suspended solid value was positively related with the partition property of target EDCs between suspended solid and seawater. Based on the results of principal component analysis, dissolved organic carbon, total nitrogen, and total phosphorous had close relationships with the distribution of target EDCs in the seawater. Temperature and dissolved oxygen had little relationship with the distribution of target EDCs in the coastal area. 相似文献
104.
105.
Ying Liu Nora Feng Yee Tam Yuntao Guan Baoyu Gao 《Water, air, and soil pollution》2012,223(7):4383-4395
The embryos of a marine abalone, Haliotis diversicolor supertexta, were exposed to a typical environmental estrogen, 17??-ethynylestradiol (EE2), for 96?h, to examine the acute toxicity of EE2 to the embryogenesis of the abalone. A marine diatom, Navicula incerta, was used in the test media as settlement substrate and food for the abalone larvae. During the embryo culture, more than 30?% of EE2 could be removed from the test media by the diatom, mainly via biodegradation, leading to a decrease of water-borne exposure dose. Further, the exposure concentrations of EE2 around the living microenvironment of the abalone larvae could be magnified 350?C468 times after the larvae settled on the diatom, as indicated by the bioconcentration factors of EE2 in the diatom. Increased bioaccumulation of EE2 in the diatom caused greater inhibition on the metamorphosis of the abalone larvae by enhancing the uptake of EE2 in the larvae via dietary exposure, while declined water-borne exposure dose did not affect the embryonic toxicity of EE2 and its uptake in the abalone larvae. The 96-h median effective concentration of EE2 to the metamorphosis of the abalone larvae was 10.01???g?L?1, when the exposure doses in both the test media and the diatom were controlled stable. The 96-h hazard concentration for 5?% of the species was 1.20???g?L?1, which was still higher than but close to the reported upper contamination level of EE2 and could be employed as the safety threshold for the metamorphosis of the abalone embryos. 相似文献
106.
根据传染性喉气管炎病毒美国632株和英国Thorne株gC基因的序列设计1对引物,以北京E2株为模板,用PCR方法扩增到长度为1.9kp的片段,并将其克隆至质粒pA-T。用碱小量法制备质粒DNA,以酶切和质粒PCR的方法对其进行了鉴定,并以正向和反向引物测定其两翼序列,结果正向引物测出498个碱基,反向引物测出499个碱基,将所得序列输入GenBank与其他毒株进行比较,结果发现其与美国632株的 相似文献
107.
108.
Sharon K. Theisen Stephen P. DiBartola DVM M. Judith Radin Dennis J. Chew C. A. Tony Buffington Steven W. Dow 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1997,11(4):212-217
Muscle potassium content and supplementation with potassium gluconate were evaluated in normokalemic cats with chronic renal failure (CRF). Affected cats received standard medical therapy for renal failure and either placebo (sodium gluconate! or potassium gluconate. At the beginning of the study and after 6 months of supplementation, glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) were estimated using 3 H-inulin and 14 C-tetraethylammo-nium bromide (TEA) clearances. Muscle potassium content was determined in biopsy specimens using atomic absorption spectroscopy. Muscle biopsy samples obtained from cats with CRF before treatment had significantly lower muscle potassium content than did those from normal control cats. Over the 6-month period of supplementation, muscle potassium content increased both in cats with CRF that received potassium gluconate and in those that received placebo (sodium gluconate). Serum potassium concentration and fractional excretion of potassium remained relatively unchanged in both groups of cats throughout the treatment period. There were no significant differences in the percentage change in GFR and ERPF between treatment groups over the 6-month time period. Median values for pH, HCO3 , and total CO2 at 6 months were higher than baseline in the potassium gluconate group but lower than baseline in the sodium gluconate group. 相似文献
109.
B A Lightner M A McLoughlin D J Chew S M Beardsley H K Matthews 《Journal of the American Veterinary Medical Association》2001,219(11):1577-1581
OBJECTIVE: To evaluate the effectiveness of episioplasty for the treatment of perivulvar dermatitis or chronic or recurrent urinary tract infections (UTI) believed to be secondary to excessive perivulvar skin folds in dogs and to document whether a causal relationship exists between the presence of chronic or recurrent UTI and excessive perivulvar skin folds in female dogs. DESIGN: Retrospective study. ANIMALS: 31 female dogs. PROCEDURE: Medical records of dogs with vulvar dermatitis (group 1; n = 15) or UTI (group 2; 16) were reviewed for history, signalment, physical examination findings, hematologic findings, results of urine or vaginal bacteriologic culture, and results of additional diagnostic procedures. RESULTS: 14 of 15 dogs in group 1 had complete resolution of perivulvar dermatitis and associated clinical signs following episioplasty. One dog had a relapse of clinical signs and vulvar dermatitis 2 years after surgery in association with a 9-kg (1 9.8-1b) weight gain. Sixteen of 16 dogs in group 2 had complete resolution of clinical signs of UTI following episioplasty. Urine samples were obtained via cystocentesis no earlier than 1 month after surgery to confirm resolution of UTI in 13 of 16 of dogs in group 2. Mild-to-moderate incisional swelling was the only surgical complication reported for either group, with the exception of 1 dog in group 2 that had wound dehiscence. All owners were satisfied with surgical outcomes. CONCLUSIONS AND CLINICAL RELEVANCE: All owners reported complete resolution of clinical signs for both groups of dogs. Episioplasty is an effective low morbidity treatment for perivulvar dermatitis and chronic UTI associated with excessive perivulvar skin folds. 相似文献
110.
Genetic diversity and toxin gene distribution among serovars of Actinobacillus pleuropneumoniae from Australian pigs 下载免费PDF全文