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1.
为确定酶解法提取菲律宾蛤仔(Ruditapes philippinarum)抗肿瘤活性多肽的最佳工艺条件,选用5种蛋白酶在相同的料液比、酶解时间和酶添加量、各自最适温度和pH的条件下酶解菲律宾蛤仔。通过甲醛电位滴定法和Cell counting kit-8(CCK-8)方法分别测定了菲律宾蛤仔酶解液氨基态氮含量和酶解多肽的抗肿瘤活性,分析了氨基态氮含量与A549抑制率之间的相关性。在单因素试验的基础上,以人非小细胞肺癌A549抑制率为指标,正交分析优化酶解工艺条件。结果显示,菲律宾蛤仔的5种酶解产物中,风味蛋白酶的酶解液中氨基态氮含量最高,而胃蛋白酶获得的酶解多肽抗肿瘤活性最高。胃蛋白酶酶解菲律宾蛤仔正交实验确定酶解最佳工艺条件为:料液比(w/w)1∶1,pH 2.0,酶解时间1 h,酶添加量2 000 U/g,酶解温度37℃。当设定最佳酶解工艺获得的酶解多肽浓度为20 mg/m L时,其对A549的抑制率为99.83%。研究表明,酶的种类对菲律宾蛤仔酶解液氨基态氮含量和酶解多肽的抗肿瘤活性有较大影响,菲律宾蛤仔酶解液中氨基态氮含量与A549抑制率没有直接的正相关性。  相似文献   

2.
采用不同质量浓度的细胞松弛素B抑制第一极体的释放,诱导菲律宾蛤仔四倍体,观察诱导各组胚胎的早期发育过程,结果表明,0.5、0.7mg/L及1.0mg/L的细胞松弛素B均能有效抑制第一极体的释放,获得四倍体诱导率分别为58.2%、55.1%及55.2%,无显著差异;随细胞松弛素B用量的升高,菲律宾蛤仔早期胚胎发育速度略有减慢,各发育阶段胚胎畸形率显著提高,畸形形式增加,孵化率降低。综合分析,0.5mg/L的细胞松弛素B适于诱导菲律宾蛤仔四倍体。  相似文献   

3.
为了评价联苯菊酯的遗传毒性,研究了不同浓度联苯菊酯对菲律宾蛤仔肝胰腺细胞DNA的损伤作用。研究分别在0.05、0.10、0.15、0.20 mg/L联苯菊酯暴露25 d后,取菲律宾蛤仔肝胰腺细胞并用单细胞凝胶电泳(彗星实验)进行分析,以彗尾DNA相对含量(TDNA%)、彗星尾长(TL)、Olive尾矩(OTM)和拖尾率(TR)作为DNA损伤的指标,实验结果表明:与空白对照组相比,各处理组菲律宾蛤仔肝胰腺细胞DNA均有不同程度的损伤且各检测指标值均显著增加(P0.05);随着联苯菊酯浓度的增加,各检测指标均呈规律性的增长趋势,具有高度的相关性(r0.99),表现出良好的剂量效应关系。评价彗星实验较好的检测指标为彗尾DNA相对含量和Olive矩,实验获得的多元回归方程具有显著的统计学意义(P0.01),可以有效地推断联苯菊酯对菲律宾蛤仔的染毒毒性浓度。  相似文献   

4.
在受控实验条件下,模拟了重金属铜、铅、镉在海水-小球藻-菲律宾蛤仔食物链中的累积和传递,测定了小球藻、菲律宾蛤仔对铜、铅、镉的富集系数以及铜、铅、镉在小球藻-菲律宾蛤仔食物链上的传递系数。结果显示,随着海水中重金属浓度的增加,小球藻、菲律宾蛤仔体内的重金属含量逐渐增大,小球藻对铜、铅、镉离子的富集系数变化范围分别为1626~3161、3295~7799、5438~9313;蛤仔对Cu、Pb、Cd的富集系数变化范围分别为364~821、1089~1936、245~736;生物传递因子变化范围分别为0.22~0.26、0.25~0.46、0.03~0.14。在本实验条件下,小球藻对Cu、Pb、Cd的富集系数远大于菲律宾蛤仔,Cu、Pb、Cd在小球藻-菲律宾蛤仔食物链上没有明显的生物放大效应。  相似文献   

5.
菲律宾蛤仔对6种重金属的生物富集动力学   总被引:1,自引:0,他引:1       下载免费PDF全文
以菲律宾蛤仔为实验生物,应用半静态双箱模型室内模拟了菲律宾蛤仔对混合暴露条件下6种重金属Cu、Zn、Pb、Cd、Hg、As的生物富集实验,通过对菲律宾蛤仔体内重金属含量变化进行非线性拟合,得到其对重金属的生物富集系数、生物富集动力学参数。结果表明,到富集实验结束时菲律宾蛤仔对高、中浓度组中Cu、Zn、Pb和Cd的生物富集系数分别是66.99、18.49、57.11、25.81和72.46、35.72、117.91、41.83,对其低浓度组中Hg和As的富集规律不明显;吸收速率常数k1及生物富集系数均随外部水体金属浓度的增加而减少;通过生物富集系数发现,菲律宾蛤仔对4种重金属的富集能力由大到小为Pb>Cu>Cd>Zn;通过χ2及F检验发现,生物双箱动力学模型可较好反映混合暴露条件下菲律宾蛤仔对重金属的富集特征。  相似文献   

6.
桑沟湾楮岛大叶藻(Zostera marina L.)床周边存在大量的底栖菲律宾蛤仔(Ruditapes philippinarum),为摸清菲律宾蛤仔的生理活动与大叶藻的相互作用,2016年5~7月,在菲律宾蛤仔和大叶藻集中分布区,评估了菲律宾蛤仔种群资源量,现场流水法测定了菲律宾蛤仔个体水平的摄食、代谢生理,围隔实验法探讨了种群水平蛤仔与大叶藻的相互作用。结果显示,桑沟湾楮岛大叶藻床海区菲律宾蛤仔的平均生物量为(572.00±20.23) ind./m2,大(壳长为3.50~4.10 cm)、中(壳长为3.00~3.50 cm)、小(壳长为2.00~3.00 cm)规格各占9.01%、43.60%和47.38%。菲律宾蛤仔的排氨率、耗氧率、滤水率、摄食率分别为(0.44±0.15)~(1.40±0.35) μmol/(ind.·h)、(0.21±0.02)~(0.33± 0.08) mg/(ind.·h)、(0.69±0.38)~(0.83±0.66) L/(ind.·h)和(2.57±0.41)~(3.41±0.68) mg/(ind.·h),且都随体重的增加而增大。围隔实验设有3个实验组(蛤仔组、大叶藻组和大叶藻+蛤仔组),1个空白组,每组3个平行(大叶藻30茎枝左右、蛤仔15个左右),实验进行4 h。研究表明,蛤仔组、大叶藻+蛤仔组和大叶藻组间的溶氧浓度存在显著差异(P<0.05);蛤仔组与其他3组的氨氮浓度存在显著差异(P<0.05);蛤仔组、大叶藻+蛤仔组与空白组的水体颗粒物浓度存在显著差异(P<0.05),大叶藻组与空白组差异不显著(P>0.05)。桑沟湾楮岛海区菲律宾蛤仔养殖面积约为0.5 km2,蛤仔每天可以过滤46 t海水中的悬浮颗粒物,并为大叶藻提供0.4 t的氨氮。本研究为深入揭示大叶藻海区菲律宾蛤仔的生态作用提供了基础数据。  相似文献   

7.
为筛选出菲律宾蛤仔17个发育时期及成体7个组织中的最适内参基因,实验采用3个内参基因筛选方法ge Norm、Norm Finder及ΔCt对菲律宾蛤仔不同发育时期和成体不同组织中的12个候选内参基因延伸因子1α基因(EF1A)、TATA盒结合蛋白基因(TBP)、组蛋白H3基因(HIS)、细胞色素b5基因(CYTB5)、泛素缀合酶基因(UCE)、核糖体蛋白L8基因(RPL8)、核糖体蛋白S23基因(RPS23)、核糖体蛋白L2基因(RPL2)、细胞色素C基因(CYTC)、生长因子受体结合蛋白2基因(GFRP2)、肌动蛋白基因(ACT)和微管蛋白基因(TUB)进行表达稳定性分析。结果显示,菲律宾蛤仔不同发育时期q RT-PCR分析需要3个内参基因,分别为CYTC、CYTB5和RPS23;菲律宾蛤仔成体不同组织q RT-PCR分析需要2个内参基因,分别为CYTB5和GFRP2。ACT在菲律宾蛤仔不同发育阶段和不同组织中表达最不稳定。  相似文献   

8.
本文以菲律宾蛤仔(Ruditapes philippinarum)为材料,开展了不同浓度b-1,3-葡聚糖对正常菲律宾蛤仔及副溶血弧菌(Vibrio parahaemolyticus)感染后蛤仔的存活率和凝集素基因(Lectin)、Toll样受体2基因(TLR2)的表达研究。结果显示,b-葡聚糖浸泡蛤仔可以有效提高副溶血弧菌感染后蛤仔的存活率,在1000 mg/L浓度下,存活率最高,未感染组的鳃组织中,TLR2在6 h时达到峰值,显著高于其他时间(P<0.05)。在感染组中,TLR2呈先升高后降低的趋势,在1.5 h时达到峰值。感染组和未感染组的Lectin表达均为先升高后下降趋势。在3 h时,100 mg/L未感染组的Lectin相对表达量显著高于100 mg/L感染组(P<0.05)。在外套膜中,感染组和未感染组TLR2在3~12 h之间表达量逐渐降低。在24 h时,1000 mg/L未感染组表达量最高。感染组Lectin在外套膜中,浓度为1000 mg/L的实验组比100 mg/L实验组各时段都有更高的表达量,但只有0和24 h时差异显著(P<0.05)。蛤仔鳃和外套膜Lectin的表达模式不同,但b-葡聚糖的浸泡都促进了Lectin在感染初期的表达。从结果上看,b-葡聚糖的浸泡会增加这2种基因的相对表达,被b-葡聚糖浸泡过的蛤仔被副溶血弧菌感染后,会更为快速地表达TLR2和Lectin。本研究旨在通过不同浸泡浓度b-葡聚糖对蛤仔存活及免疫基因表达的影响,初步了解b-葡聚糖对蛤仔免疫力的作用,为蛤仔亲贝的保种、苗种繁育及池塘养殖的疾病防控提供一定的理论依据。  相似文献   

9.
本文以菲律宾蛤仔(Ruditapes philippinarum)为材料,开展了不同浓度β-1,3-葡聚糖对正常菲律宾蛤仔及副溶血弧菌(Viβrio parahaemolyticus)感染后蛤仔的存活率和凝集素基因(Lectin)、Toll样受体2基因(TLR2)的表达研究。结果显示,β-葡聚糖浸泡蛤仔可以有效提高副溶血弧菌感染后蛤仔的存活率,在1000 mg/L浓度下,存活率最高,未感染组的鳃组织中,TLR2在6 h时达到峰值,显著高于其他时间(P0.05)。在感染组中,TLR2呈先升高后降低的趋势,在1.5 h时达到峰值。感染组和未感染组的Lectin表达均为先升高后下降趋势。在3 h时,100 mg/L未感染组的Lectin相对表达量显著高于100 mg/L感染组(P0.05)。在外套膜中,感染组和未感染组TLR2在3~12 h之间表达量逐渐降低。在24 h时,1000 mg/L未感染组表达量最高。感染组Lectin在外套膜中,浓度为1000 mg/L的实验组比100 mg/L实验组各时段都有更高的表达量,但只有0和24 h时差异显著(P0.05)。蛤仔鳃和外套膜Lectin的表达模式不同,但β-葡聚糖的浸泡都促进了Lectin在感染初期的表达。从结果上看,β-葡聚糖的浸泡会增加这2种基因的相对表达,被β-葡聚糖浸泡过的蛤仔被副溶血弧菌感染后,会更为快速地表达TLR2和Lectin。本研究旨在通过不同浸泡浓度β-葡聚糖对蛤仔存活及免疫基因表达的影响,初步了解β-葡聚糖对蛤仔免疫力的作用,为蛤仔亲贝的保种、苗种繁育及池塘养殖的疾病防控提供一定的理论依据。  相似文献   

10.
本研究通过在养殖水体中添加底泥或单胞藻调节悬浮颗粒浓度,研究了悬浮物数量浓度和质量浓度变化对文蛤(Meretrix meretrix)、硬壳蛤(Mercenaria mercenaria)和菲律宾蛤仔(Ruditapes philippinarum)保留效率的影响。结果显示,文蛤、硬壳蛤及菲律宾蛤仔的保留效率分别在粒径为8、6和6 μm时达到最大值,分别为51.1%、59.6%和62.6%。随着数量浓度的增加,文蛤在低(4.32× 107 cells/L)、中(5.27×107 cells/L)、高(6.65×107 cells/L) 3个数量浓度下保留效率达到最大值时的最小粒径逐渐增大,分别为9、13和14 μm,保留效率最大值分别降至49.7%、33.4%和26.2%;与文蛤相似,菲律宾蛤仔保留效率达到最大值时的最小粒径也分别增大至9、12和14 μm,但最大保留值无明显变化;硬壳蛤保留效率的最大值保持不变,但达到最大值时的最小粒径略有增大,分别为8、9和10 μm。随质量浓度的增加,文蛤和菲律宾蛤仔在低(5.7 mg/L)、中(11.8 mg/L)、高(23.3 mg/L) 3个质量浓度下的保留效率最大值和达到最大值时的最小粒径均无明显变化;硬壳蛤保留效率最大值显著降低,分别为60.7%、27.6%和25.5%,但保留效率达到最大值时的最小粒径保持不变。研究表明,文蛤和菲律宾蛤仔的保留效率对食物颗粒数量浓度变化更敏感,而硬壳蛤的保留效率受质量浓度变化影响较大。  相似文献   

11.
The objectives of this study were to investigate: 1) the pharmacokinetics of dietary icosapentaenoic acid (EPA) in the plasma using 13C‐labeled EPA ([13C]EPA); 2) the bioavailability of [13C]EPA with different chemical forms; and 3) an effective plasma EPA level for normal growth of the Japanese flounder Parachthys olivaceus. [13C]EPA was biosynthesized using the Chlorella Nannochloropsis oculate, and 1‐myristoyl 2‐[13C]icosapentaenoyl phasphatidyl‐choline ([13C]EPA‐PC) and [13C]EPA ethyl ester ([13C]EPA‐EE) were chemically synthesized from [13C]EPA. Free [13C]EPA ([13C]EPA‐FREE) dissolved in 0.5% tragacanth gum‐polye‐thyleneglycol (3:1, V/V) was administered to the Japanese flounder at dosages of 2.8, 5.6, and 16.8 mg/kg by a single oral administration. [13C]EPA‐PC (44.8 mg/kg) and [13C]EPA‐EE (18.3 mg/kg), equimolar to 3.0 mg [13C]EPA‐FREE (16.8 mg/kg), were administered to the fish in a similar manner. In [13C]EPA‐FREE dosed fish, the kinetics of the mean plasma [13C]EPA were linear with respect to dose. [13C]EPA‐FREE and [13C]EPA‐PC were more efecient in maintaining high plasma EPA levels than [13C]EPA‐EE in the Japanese flounder. [13C]EPA was distributed in plasma, blood cell, eyeball containing the orbital fat, liver, stomach, intestine, skin, brain, heart and muscle in three [13C]EPA derivatives studies. The effective plasma EPA level for normal growth of the Japanese flounder is estimated to be 307 to 937 μg/mL for EPA‐FREE administration, and from 286 to 815 μg/mL 6.3 to 38 mg/mL for the EPA‐PC administration.  相似文献   

12.
Abstract Factors that can influence changes in lipid class concentrations in specific tissues have not been reported for largemouth bass Micropterus salmoides. We investigated patterns of lipid composition by measuring seasonal levels of total lipid and major lipid classes in the muscle and liver tissues of juvenile and adult largemouth bass and gonad tissue of adults. Fish were collected in December, February, April and July to correspond with key stages of the sexual cycle. Total lipid concentrations were substantially greater in hepatic (32.8 [female] to 56.6 [male] mg. g?1) and gonadal tissues (34.4 [F] to 204.0 [M] mg. g?1) than in muscle (7. 5 [F] to 11.4 [M] mg. g?1). Muscle lipid concentrations in juveniles were significantly higher (10.9 [F] and 11.4 [M] mg. g?1) in summer than in winter in adult muscle tissue (8.6 [F] and 9.4 [MI mg. g?1). A 44% increase in ovary lipid was observed from preparatory to prespawn stages, followed by a 78% decline after the spawn. Additionally, seasonal hepatic lipid concentrations were substantially higher in juveniles. Concentrations of lipid classes (free cholesterol [C], triacylglycerol [TAG], free-fatty acids [FFA], esterified cholesterol [CE] and phospholipid [PL]) of all tissue types varied significantly among season, sex, and maturity categories. Changes with all lipid classes in the ovary coincided with those occurring in total ovarian lipid. Mobilization and transport of TAG and PL from the liver to the ovary appeared to occur during gametogenesis. All class concentrations in juveniles were invariably higher in liver than in muscle, but seasonally variable among hepatic and gonad tissues of adults. Juvenile males showed slightly greater hepatic C concentrations than other groups. Muscle and hepatic C were generally higher in juveniles.  相似文献   

13.
吕程  方勤学  施飞 《畜禽业》2009,(10):30-32
目的:比较氮酮、二甲基亚砜(DMSO)2种透皮促进剂对盐酸左旋咪唑(LMS)的促透效果,为临床应用左旋咪唑透皮系统(TDDS)提供参考依据。方法:通过家兔体外透皮试验,以单位面积LMS的透皮量(Q)作为考核指标,用非水滴定法作为检测手段,考查1%、3%、5%、7%4个浓度透皮促进剂的促透效果。结果:3%氮酮及7%DMSO较其他浓度有较好的促透效果。其中含有3%氮酮的LMS透皮剂透皮效果最好。结论:可考虑临床应用3%浓度的氮酮作为LMS透皮系统的促进剂。  相似文献   

14.
Hirosuke  OKU  Hideyuki  YAMASHIRO  Kyoko  ONAGA 《Fisheries Science》2003,69(3):625-631
ABSTRACT:     Glucose has been implicated in functioning as a form of carbon translocated from symbiont zooxanthellae to the host coral cell. The present paper describes the lipid biosynthesis from [14C]-glucose in the coral tissue. To study the incorporation of [14C]-glucose into lipids, the branch tips of the coral Montipora digitata were incubated with [14C]-glucose or another radiolabeled substrates. The lipid biosynthesis from [14C]-glucose was dependent on light, and was decreased by dark conditions or by photosystem II inhibitor, 3-(3,4-dichlorophenyl)-1,1-dimethylurea. Of the lipid classes, the light dependency was more pronounced with the biosynthesis of triacylglycerols (TG) and wax compared with phospholipids. Examination of [14C]-label distribution in the glycerolipids suggested that [14C]-glucose supplied mainly the fatty acid moiety of newly synthesized TG, while [14C]-glucose provided evenly the fatty acid moiety and the glycerol skeleton of phospholipids. The comparison of [14C]-labeling of lipid from host coral tissue and symbiont zooxanthellae suggested that [14C]-glucose entered the coral cell and was processed in parallel in the zooxanthellae and host cells. Furthermore, the coral cells used various [14C]-labeled sugars for lipid synthesis with similar lipid labeling profile as was the case for glucose. The current study thus supports the view that the low-molecular-weight compound, sugars and amino acids, once translocated from zooxanthellae to host cell were metabolized toward lipogenesis as well as glycerol.  相似文献   

15.
It is well known that healthy gut microbiota is essential to promote host health and well‐being. The intestinal microbiota of endothermic animals as well as fish are classified as autochthonous or indigenous, when they are able to colonize the host's epithelial surface or are associated with the microvilli, or as allochthonous or transient (associated with digesta or are present in the lumen). Furthermore, the gut microbiota of aquatic animals is more fluidic than that of terrestrial vertebrates and is highly sensitive to dietary changes. In fish, it is demonstrated that [a] dietary form (live feeds or pelleted diets), [b] dietary lipid (lipid levels, lipid sources and polyunsaturated fatty acids), [c] protein sources (soybean meal, krill meal and other meal products), [d] functional glycomic ingredients (chitin and cellulose), [e] nutraceuticals (probiotics, prebiotics, synbiotics and immunostimulants), [f] antibiotics, [g] dietary iron and [h] chromic oxide affect the gut microbiota. Furthermore, some information is available on bacterial colonization of the gut enterocyte surface as a result of dietary manipulation which indicates that changes in indigenous microbial populations may have repercussion on secondary host–microbe interactions. The effect of dietary components on the gut microbiota is important to investigate, as the gastrointestinal tract has been suggested as one of the major routes of infection in fish. Possible interactions between dietary components and the protective microbiota colonizing the digestive tract are discussed.  相似文献   

16.
The black‐lipped pearl oyster, Pinctada margaritifera, is the most important farmed mollusc species in French Polynesia. Donor oyster selection among wild P. margaritifera individuals, chosen according to their inner shell colour, makes it possible to obtain the broadest range of cultured pearl colours of any species. This study demonstrates the relative influence of using black [B] or red [R] outer shell phenotypes, combined with green [G] or yellow [Y] inner shell phenotypes, on pearl darkness level, colour categories and lustre. A large scale grafting experiment was designed and carried out over five grow‐out locations, covering three archipelagos: Tuamotus, Society and Gambier. Results revealed that the [B + G] phenotypes may be used as donors to produce dark green pearl, which suit the demands of the Asian market; whereas, phenotypes incorporating [R] and/or [Y] phenotypes may be used to obtain multicolour pearls of medium/light darkness, which suit the demands of the European market. From an environmental point of view, the 1) [B] phenotype showed no significant variation for light and other pearl colour production, and 2) [Y] phenotype produced both the same rate of pearl darkness level and green colour pearls whatever the grow‐out location. A classification tree model was built to predict, according to shell phenotype and culture location, the colour and darkness level of harvested pearls. Lustre was shown to be more influenced by the environment than by phenotype. These results should be taken into account in pearl farm production management and in selective breeding programmes.  相似文献   

17.
张婷  许嘉敏  黄淑丹  陶宁萍  王锡昌  钟建 《水产学报》2022,46(11):2241-2255
明胶是由胶原蛋白部分降解得到的天然多肽聚合物,具有良好的乳化性、成膜性、发泡性和凝胶性以及生物相容性和生物可降解性,在食品加工业中有着广泛应用。哺乳动物明胶占明胶市场的主要份额,但由于存在宗教因素和健康方面的担忧,哺乳动物明胶在食品加工业中的应用受到限制和质疑。鱼皮明胶与哺乳动物明胶具有相似的功能性质,且由于鱼皮明胶来源独特,并能满足伊斯兰教等具有特殊文化和需求人群的要求,已逐渐成为食品加工业中的重点研究对象。为了综合介绍鱼皮明胶在食品中的应用,本文综述了鱼皮明胶作为乳化剂、发泡剂、澄清剂、增稠剂和胶凝剂以及可食用包装、可食用涂层、乳液、微胶囊、纳米纤维和水凝胶制备材料在食品加工业中的研究进展。鱼皮明胶的功能特性使其在食品加工业中可作为食品添加剂、食品包装材料和活性物包裹材料并显示出优于哺乳动物明胶的生物安全性和加工特性。由此可见,鱼皮明胶在食品加工业中具有良好的应用前景,并有望成为哺乳动物明胶的良好替代品。本综述可为今后进一步提高鱼皮明胶的功能性质和扩大鱼皮明胶在食品中的应用提供一定指导。  相似文献   

18.
The effect of cortisol on the in vitro metabolism of [3H]17-hydroxyprogesterone ([3H]17OHP) was studied during embryonic development of Arctic charr (Salvelinus alpinus) and rainbow trout (Oncorhynchus mykiss). In the absence of cortisol, rainbow trout embryos metabolized [3H]17OHP largely to androstenedione (A4) and androstenetrione (11-KA) with a minor conversion to 17,20ß-dihydroxy-4-pregnen-3-one (17,20P). In the presence of cortisol, this biosynthesis was inhibited. On the other hand, cortisol had no apparent inhibitory effect on the nature of metabolism of [3H]17OHP by Arctic charr embryos. In these embryos [3H]17OHP was metabolized mainly to 17,20P with a minor conversion to A4 and without the formation of 11-KA that was seen in rainbow trout.When incubated in the presence of [3H]cortisol both Arctic charr and rainbow trout embryos produced 11ß-hydroxyandrostenedione (11ß-OHA) as the major metabolite, with a minor conversion to an unknown steroid. The catabolism of the cortisol by salmonid embryos may reflect the ability of the embryo to inactivate or detoxify cortisol to protect itself from the adverse effects of this biologically potent steroid hormone The study indicates the existence of species-specific differences in the nature of metabolism of [3H]17OHP and the inhibitory effect of cortisol on this metabolism.  相似文献   

19.
【目的】研究米氏碘泡虫(Myxobolus miyairii Kudo, 1919)不同寄生部位和不同地理分布的株系差异和遗传分化情况。【方法】基于形态特征、组织向性、地理分布、18S rDNA序列相似度、遗传距离、系统发育,对米氏碘泡虫各株系进行比较分析。【结果】米氏碘泡虫各株系孢子形态特征基本一致;米氏碘泡虫重庆株系1(鲶鳃腔膜寄生),重庆株系2(鲶肠寄生)和江西株系(鲶肠寄生)间相似度为98.6%~99.9%,遗传距离为0.000~0.013;系统发育分析显示,米氏碘泡虫重庆株系2先与江西株系聚支,其形成的进化支再与重庆株系1形成姐妹群关系。【结论】序列比较和系统发育分析结果表明,米氏碘泡虫并没有形成地理种群特有的单系,而是依据寄生部位形成肠寄生支系和鳃腔膜寄生支系。宿主种类相同的条件下,较之于地理隔离,寄生部位差异对于米氏碘泡虫种群分化的影响更大。【意义】本文米氏碘泡虫各株系的比较研究及其结果,为人们进一步了解该寄生虫的进化生物学特征积累基础资料。  相似文献   

20.
The activities of Phase I and Phase II biotransformation enzymes in the livers of yearling coho salmon (Oncorhynchus kisutch), were measured biweekly from February until the release date from the hatchery in mid-June, in order to observe any alterations in baseline levels during smoltification. Peak enzyme activities occurred in February and March and then declined through to June. Total cytochrome P450 levels ranged from 0.024±0.009 to 0.095±0.010 nmol mg-1 microsomal protein, ethoxyresorufin O-deethylase activity ranged from 2.74±0.75 to 9.94±0.85 pmol min-1 mg-1 microsomal protein, and glutathione S-transferase activity ranged from 0.07±0.01 to 0.33±0.01 μmol min-1 mg-1 cytosolic protein during this period. Following an intraperitoneal injection of [3H]benzo[a]pyrene (B[a]P), elimination occurred rapidly (>71% excreted into the bile within 24h) from February to June. Although the distribution of B[a]P in tissues changed through the sampling period, the highest leels of B[a]P-derived radioactivity were found in the liver, bile and fat. Analysis of the bile revealed that 55 to 63% of the radioactivity was Phase I metabolites, 16 to 24% glucuronide conjugates, 8% sulfate conjugates, 7% other conjugates and 6% aqueous-soluble metabolites. These findings suggest that the transformation from freshwater adapted coho ‘parr’ to ‘smolts’, can significantly alter biotransformation enzyme activities and the distribution and elimination of xenobiotics such as benzo[a]pyrene in these fish. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

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