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1.
荧光聚苯乙烯微球对蝌蚪应激水平和免疫功能的影响   总被引:1,自引:0,他引:1  
为探究纳米塑料对黑斑侧褶蛙(Pelophylax nigromaculatus)37期蝌蚪健康状态的影响,将其暴露于50 nm粒径低、中和高浓度荧光聚苯乙烯微球溶液(fluorescent polystyrene microsphere solution, FPMS)7 d(7 d时),之后分别移至清水中饲养7 d(14 d时)或14 d(21 d时),以清水组为对照组,测定了每一取样时间点不同浓度组、同一浓度组不同取样时间点的体重与体全长的比值(重长比)、嗜中性粒细胞与淋巴细胞的比值(N/L)和对植物血凝素(phytohemagglutinin, PHA-P)的反应差异。结果表明:重长比只在14 d时清水组显著低于其他浓度组;N/L只在21 d时清水组低于其他浓度组,低、中和高浓度组都从7 d时至21 d时显著增加;7 d时各浓度组蝌蚪对PHA-P的最大反应值出现于注射后3 h或4 h, 14 d时前移至2 h或3 h, 21 d时又恢复至3 h或4 h,只有21 d时高浓度组高于低浓度组和中浓度组;FPMs暴露和初次清除对黑斑侧褶蛙蝌蚪的生长发育有明显的促进作...  相似文献   

2.
摘要 目的:探究4个炎症因子Toll样受体4(TLR4)、TNF受体相关因子6(TRAF6)、白细胞介素-6(IL-6)和白细胞介素-1β(IL-1β)在深静脉血栓大鼠体内的表达及在深静脉血栓形成的作用。方法:将SD大鼠随机分成对照组(n=10)和模型组(n=90),采用血管钳夹结合固定制动的方式建立深静脉血栓模型,建模后分别于1 h、6 h、12 h、1 d、3 d、7 d、14 d、21 d、28 d处死,检测血栓重量/长度比值、血浆中4个炎症因子的浓度,并进行组织学观察。结果:(1)1 h、6 h、12 h的血栓重量/长度比值较低,组间无显著性差异(P>0.05);1 d、3 d、7 d的血栓重量/长度比值维持在较高水平,组间无显著性差异(P>0.05);14 d、21 d、28 d的血栓重量/长度比值均降低,组间无显著性差异(P>0.05)。(2)模型组中1-7 d的血栓重量/长度比值均明显高于正常组(P<0.05)。(3)模型组中1-7 d的TLR4、TRAF6、IL-6和IL-1β浓度水平均明显高于正常组(P<0.05)。(4)Pearson 相关性分析显示TLR4、TRAF6、IL-6和IL-1β浓度与血栓程度具有正相关性。结论:深静脉血栓大鼠体内的TLR4、TRAF6、IL-6和IL-1β表达上调可能在深静脉血栓形成中发挥了重要作用。  相似文献   

3.
以柠檬香蜂草(Melissa officinalis)幼苗为材料,设置不同浓度Cu~(2+)胁迫(CK、200、400、800和1 000mg·kg~(-1))盆栽实验,测定胁迫0、7、14、21、28d后植物生物量、叶绿素含量、抗氧化酶活性、可溶性蛋白含量、丙二醛(MDA)含量以及植物体内Cu含量等指标,探讨柠檬香蜂草对Cu~(2+)的耐受性及其积累特征。结果表明:(1)相同处理时间下,柠檬香蜂草除MDA含量外其他所有指标均随着Cu~(2+)胁迫处理浓度的增加呈低浓度促进、高浓度抑制的变化趋势,且高浓度组(800和1 000mg·kg~(-1))与低浓度组(200和400mg·kg~(-1))之间差异显著(P0.05);MDA含量在1 000mg·kg~(-1)浓度下持续增长至第14天后开始下降。(2)柠檬香蜂草体内Cu的积累量随Cu胁迫浓度的升高呈先增加后减少的趋势,并在浓度为400mg·kg~(-1)时达到最高值(0.71mg/盆)。(3)在整个胁迫过程中,柠檬香蜂草植株的铜富集系数及其耐性系数均随Cu浓度的增加而减小,各处理浓度对Cu的耐性系数均大于0.5,富集系数均大于1。研究发现,柠檬香蜂草对Cu胁迫具有一定耐受性和富集能力,具有成为铜污染土壤修复植物的潜力。  相似文献   

4.
饥饿和再投喂对鲇血液生理生化指标的影响   总被引:5,自引:1,他引:4  
在室内可控条件下,对鲇(Silurus asotusLinnaeus)进行7d、14d和21d的饥饿处理,随后各组恢复投喂20d,研究饥饿和再投喂对鲇血液生理生化指标的影响。结果显示:饥饿过程中,鲇血液红细胞数和血红蛋白14d内上升,血红蛋白上升显著(p〈0.05),21d后两项生理指标开始下降;饥饿7d后血糖浓度显著下降(p〈0.05),饥饿14d和21d后趋于相对稳定;总蛋白、白蛋白和球蛋白均呈下降趋势,分别在饥饿的14d、7d和21d后与饥饿前达到显著性差异(p〈0.05);甘油三酯和总胆固醇分别在饥饿7d和21d后显著下降(p〈0.05);饥饿14d后Na+和Cl-浓度显著下降(p〈0.05),21d后Na+浓度却又显著上升(p〈0.05),Cl-浓度有所回升;Ca2+浓度在饥饿过程中逐渐下降,且差异显著(p〈0.05)。饥饿对K+浓度和碱性磷酸酶活力没有明显影响。恢复投喂20d后,测定的血液指标均有不同程度的恢复。采用二元三次方程(CUB类型)就各项生理生化指标对饥饿时间(d)进行的回归分析表明,Ca2+与饥饿时间的决定系数(R2)最大,为0.964,因此将鲇血液的Ca2+浓度作为其饥饿的评价指标则相对可信。  相似文献   

5.
目的:探讨酒精对丙酸睾酮引起的小鼠前列腺增生(BPH)的作用及其生殖毒性。方法:成年雄性昆明系小鼠70只随机分为空白对照组(Control)、阴性对照组(Negative control,sc大豆油25 mg/(kg·d),ig蒸馏水7.5 ml/(kg·d),连续处理7 d、21 d)、酒精7 d和21 d组(AL7和AL21,ig 50°白酒7.5 ml/(kg·d),连续处理7 d、21 d),丙酸睾酮7 d和21 d组(TP7和TP21,sc丙酸睾酮注射液25 mg/(kg·d),连续处理7 d、21 d),丙酸睾酮+酒精7 d组(TP+AL7,sc丙酸睾酮注射液25 mg/(kg·d),ig50°白酒7.5 ml/(kg·d),连续处理7 d),每组10只。末次处理24 h后处死小鼠,计算小鼠前列腺和睾丸系数,检测精子参数,测定睾丸和前列腺组织中自由基水平、抗氧化能力,观察前列腺组织病理学变化。结果:与对照组、TP7 d组、AL7和AL21 d组相比,TP+AL7 d组的前列腺系数显著提高、精子数量和质量显著降低、前列腺和睾丸MDA含量显著升高、SOD和GPx酶活力显著下降(P均< 0.05);与TP21 d组相比,TP+AL7 d组的前列腺系数无显著差别(P>0.05))。结论:丙酸睾酮和酒精共同处理7 d就可以达到典型的前列腺增生(BPH)状态,并引起睾丸及精子的损伤,导致生殖系统的氧化应激反应增强,说明酒精对丙酸睾酮引起的小鼠前列腺增生有明显的促进作用。  相似文献   

6.
目的探讨青藤碱(SIN)对人外周血CD4^+T淋巴细胞增殖和细胞内Ca^2+浓度的体外影响及其效应机制。方法建立体外人外周血CD4^+T淋巴细胞模型,分别作以下处理:(1)空白对照组;(2)环孢素(CsA)组(50ng/m1);(3)低浓度SIN组(10μmol/1);(4)中浓度SIN组(200μmol/1);(5)高浓度SIN组(1000μmol/1)。分别用MTT比色法和流式细胞术(FCM)检测CD4^+细胞增殖和细胞内Ca^2+荧光强度。采用方差分析比较各组间差异的统计学意义。结果(1)高浓度SIN组、中浓度SIN组与其他各组细胞增殖抑制率存在差异(F=1444.228,P=0.000);(2)FCM检测细胞内Ca^2+浓度结果:中浓度SIN组、高浓度SIN组与其他各组差异有统计学意义(F=479.055,P=0.000);(3)经SIN处理后,人外周血CD4^+T淋巴细胞增殖抑制率和细胞内Ca^2+浓度之间存在负相关r=-0.836,P=0.005)。结论SIN能浓度依赖性地抑制人外周血CD4^+T淋巴细胞增殖和细胞内Ca^2+浓度升高,人外周血CD4^+T淋巴细胞增殖抑制率和细胞内Ca^2+浓度之间存在显著性负相关。  相似文献   

7.
摘要 目的:探讨与分析西咪替丁对坏死性小肠结肠炎(NEC)小鼠炎症免疫反应、肠道微生物的影响。方法:将建模成功的坏死性小肠结肠炎小鼠36只随机平分为三组-模型组、西咪替丁1组、西咪替丁2组,每组12只,每组每日分别灌胃生理盐水0.1mL、胃西咪替丁0.1 mL、胃西咪替丁0.2 mL,持续应用14 d,观察小鼠炎症免疫反应、肠道微生物变化情况。结果:西咪替丁1组、西咪替丁2组治疗第7 d、第14 d的体重都显著高于模型组(P<0.05),西咪替丁2组与西咪替丁1组对比有显著提高(P<0.05)。西咪替丁1组、西咪替丁2组治疗第14 d的肠组织白介素-2含量低于模型组(P<0.05),白介素-10含量高于模型组(P<0.05),西咪替丁2组与西咪替丁1组对比有显著差异(P<0.05)。西咪替丁1组、西咪替丁2组治疗第14 d的粪便双歧杆菌、乳酸杆菌相对表达水平显著高于模型组(P<0.05),大肠埃希菌相对表达水平显著低于模型组(P<0.05),西咪替丁2组与西咪替丁1组对比有显著差异(P<0.05)。西咪替丁1组、西咪替丁2组治疗第14 d的肠组织CaMKIV、CREM蛋白相对表达水平都显著低于模型组(P<0.05),西咪替丁2组与西咪替丁1组对比也显著降低(P<0.05)。结论:西咪替丁在坏死性小肠结肠炎小鼠的应用能调节炎症免疫反应平衡,促进小鼠体重恢复正常,还可降低肠组织CaMKIV、CREM蛋白相对表达水平,从而改善小鼠肠道微生物状况,且具有剂量依赖性。  相似文献   

8.
摘要 目的:探讨术后早期散瞳对糖尿病视网膜病变(DR)合并白内障患者眼部血流动力学的影响,分析影响散瞳后瞳孔直径达标的相关因素。方法:选择2018年1月至2022年1月河北北方学院附属第一医院收治的150例行白内障手术治疗的DR合并白内障患者,将患者按随机数字表法分为对照组和观察组,两组术后均给予复方托吡卡胺滴眼液散瞳,对照组于术后7 d、14 d各散瞳1次,观察组给予早期散瞳治疗,即术后次日开始每日散瞳1次。比较两组术后眼部血流动力学变化。根据术后第14 d散瞳后瞳孔直径是否达标分为达标组(瞳孔直径≥5 mm)和未达标组(瞳孔直径<5 mm),收集患者临床资料,采用多因素Logistic回归分析影响散瞳后瞳孔直径达标的因素。结果:观察组术后14 d视网膜中央动脉、睫状后短动脉舒张末期血流速度(EDV)、收缩期速度峰值(PSV)较术后7 d增加(P<0.05),阻力指数(RI)较术后7 d降低(P<0.05),且术后7 d、14 d视网膜中央动脉、睫状后短动脉EDV、PSV高于对照组(P<0.05),RI低于对照组(P<0.05)。观察组术后14 d散瞳时间较术后7 d缩短(P<0.05),散瞳后瞳孔直径较术后7 d增大(P<0.05),且观察组术后7 d、14 d散瞳时间短于对照组(P<0.05),散瞳后瞳孔直径大于对照组(P<0.05)。糖尿病病程>10年、DR增殖期是影响散瞳后瞳孔直径达标的危险因素(P<0.05),术后早期散瞳治疗是其保护因素(P<0.05)。结论:DR合并白内障患者经白内障术后早期散瞳治疗可缩短散瞳时间,改善眼部血流动力学,增加散瞳后瞳孔直径。糖尿病病程、DR严重程度、术后散瞳时机是散瞳后瞳孔直径达标的影响因素。  相似文献   

9.
摘要 目的:探讨象皮生肌膏对肛瘘术后模型大鼠炎症因子、p38/MK2信号通路和创面组织血管内皮生长因子(VEGF)、碱性成纤维细胞生长因子(bFGF)表达的影响。方法:选择雄性SD大鼠60只,按随机数字表法分为象皮生肌膏组、模型组和假手术组,每组20只,象皮生肌膏组和模型组进行肛瘘术后创面造模,分别给予象皮生肌膏治疗及普通换药治疗。假手术组构建创面后滴加生理盐水造模,给予普通换药治疗。统计治疗后3 d、7 d、14 d创面愈合率、创面水肿积分;对比治疗后14 d血清白细胞介素-1(IL-1)、白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)水平和治疗后3 d、14 d创面组织VEGF、bFGF、p38、MK2、磷酸化p38(p-p38)、磷酸化MK2(p-MK2)表达。结果:治疗后7d、14d象皮生肌膏组创面愈合率高于模型组,但低于假手术组(P<0.05);治疗后7 d、14 d假手术组创面水肿积分低于象皮生肌膏组,且象皮生肌膏组低于模型组(P<0.05)。治疗后14 d象皮生肌膏组血清IL-1、IL-6、TNF-?琢水平低于模型组,但高于假手术组(P<0.05)。治疗后14 d象皮生肌膏组创面组织VEGF、bFGF水平高于模型组,但低于假手术组(P<0.05)。治疗后14 d象皮生肌膏组创面组织p38、MK2蛋白水平低于模型组,但高于假手术组,p-p38、p-MK2蛋白水平高于模型组,但低于假手术组(P<0.05)。结论:象皮生肌膏可以减轻大鼠肛瘘术后创面水肿程度,促进创面愈合。其主要机制可能与象皮生肌膏可降低大鼠血清炎症因子水平,抑制p38/MK2信号通路,促进VEGF和bFGF表达有关。  相似文献   

10.
目的:研究不同浓度孕酮( PRO)暴露对雌性食蚊鱼( Gambusia affinis)的形态雄性化生物学效应。方法将性未成熟的雌性食蚊鱼个体分别静水暴露于0.5、5、50和500 nmol/L不同浓度的PRO实验组中,并设置对照组和平行组。持续暴露42 d后观察与测定食蚊鱼的体长、体重、臀鳍第3鳍条和第14,15,16椎肋骨形态雄性化变化等指标,同时观察卵巢发育状况。结果食蚊鱼暴露42 d后,与对照组相比,50和500 nmol/L实验组食蚊鱼的体长( BL)有极显著减少(分别P<0.01);无论是低浓度组还是高浓度组,暴露实验后体重( BW)都有显著性或极显著下降(P<0.05或P<0.01);PRO暴露对食蚊鱼身体健康指数(CF)的影响,只有在5 nmol/L浓度时差异有显著性(P<0.05);500 nmol/L浓度处理后,第3臀鳍条分节数(FJ)、长度(FL)和最宽处宽度(FW)差异有显著性(P<0.05),表明形态雄性化变化明显;其他浓度组则无明显区别(P>0.05);500 nmol/L PRO实验组中,雌性食蚊鱼的第14,15,16椎肋骨的L值、D值和L:D值都出现极显著性差异(分别P<0.01),表明形态雄性化变化明显;组织切片观察揭示,暴露组食蚊鱼卵巢中的卵母细胞发育受到不同程度的抑制,II、III时相卵母细胞胞核发生肿胀现象。结论孕激素暴露诱导雌性食蚊鱼形态雄性化的生物效应十分明显。  相似文献   

11.
通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.  相似文献   

12.
Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m−2 s−1. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to Pfr.  相似文献   

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14.
真菌类遗传学分析的知识结构教学   总被引:5,自引:2,他引:3  
罗桂花 《遗传》2002,24(3):349-350
本文以认知结构理论为指导,讨论了真菌类遗传分析与高等动植物遗传分析的内在联系,认为利用这种内在联系进行教学可收到好的效果并说明了作者的具体教学过程。 Abstract:In the paper, the relationship between genetic analysis of Fungi and genetic analysis of high animal and plant was discussed.A good results were obtained when we adopted this method in the teaching.  相似文献   

15.
The levels of endogenous phytohormones and respiratory rate in nine sorts of flowers such as Cymbidium faberi Rolfe, Nopalxochia ackermannii Kunth and others were investigated both at full bloom and senescence and meanwhile the effect of exogenous phytohormones on prolonging the blossoms and promoting ethylene production were tested. There is a high content of endogenous ethylene in all the long-lived flowere, about 3–16 folds higer than the short-lived ones. There is a high level of ABA at full blooming flowers of short-lived flowers, in which there is no or only some cytokinins in it, but the ratio of CTK (6BA+zeatin)/ABA is smaller(l.7). The endogenous ABA reached a much higher level at senescence in all nine sorts of flowers, so it is reasonable to consider that it is ABA which plays an important role of regulation in controlling flower's senescence. There is a much higher level of GA3 and zeatin in the long-lived flowers which is not demonstrated in the shortlived ones. The respiratory rate is one of the factors controtling the longevity of flowers, but it does not play a decided role. Application of 6BA and zeatin prolongs distinctly orchid’s longevity, however exogenous IAA through the promotive action on ethylene production, evidently extends the longevity of the flowers of the Nopalxochia ackermannii Kunth.  相似文献   

16.
A complex analysis of seasonal fluctuations of the mean group parameters of the system of regulation of lipid peroxidation has been performed in liver of Balb/c mice. Association of lipid characteristics and morphophysiological parameters is studied in the Balb/c mouse liver. An inter-connection is revealed between the liver index and the amount of lysoforms of phospholipids, the scale and character of the interconnection differing essentially depending on proportion of phos-phatidylcholine in mouse liver phospholipids.  相似文献   

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龙胆科药用植物化学成分的研究现状   总被引:16,自引:0,他引:16  
龙胆科植物在我国的分布范围很广,且多数为药用植物,其多数种属的药用植物,至今其化学成分尚未被系统研究。综述了目前龙胆科药用植物的化学成分的研究现状及一般提取方法,对近年来发现的环烯醚萜及裂环烯醚萜类化合物进行了总结,为本科药用植物的更深入研究提供了参考。  相似文献   

19.
Seven strains of aerobic carbon monoxide-oxidizing bacteria (carboxydebacteria) when growing on CO as sole source of carbon and energy had doubling times which ranged from 12–42 h. The activity profiles obtained after discontinuous sucrose density gradient centrifugation indicated that the CO-oxidizing enzymes are soluble and the hydrogenases are membrane-bound in all strains examined. The CO-oxidizing enzymes of Pseudomonas carboxydohydrogena, Pseudomonas carboxydoflava, Comamonas compransoris, and the so far unidentified strains OM2, OM3, and OM4 had a molecular weight of 230,000; that of Achromobacter carboxydus amounted to 170,000. The molecular weights of the CO-oxidizing and H2-oxidizing enzymes turned out to be identical. The cell sonicates were shown to catalyze the oxidation of both CO and H2 with methylene blue, thionine, phenazine methosulfate, toluylene blue, dichlorophenolindophenol, cytochrome c or ferricyanide as electron acceptors. Methyl viologen, benzyl viologen, FAD+, FMN+, and NAD(P)+ were not reduced. The spectrum of electron acceptors was identical for all strains tested. Neither free formate, hydrogen nor oxygen gas were involved in the CO-oxidation reaction. Methylene blue was reduced by CO at a 1:1 molar ratio. The results indicate that CO-oxidation by carboxydobacteria is catalyzed by identical or similar enzymes and that the reaction obeys the equation CO+H2OCO2+2H++2e- as previously shown for Pseudomonas carboxydovorans.Dedicated to Otto Kandler remembering almost three decades of enjoyable cooperation  相似文献   

20.
Since the introduction of the concepts of allostery about four decades ago, much advancement has been made in elucidating the structure-function correlation in allostery. However, there are still a number of issues that remain unresolved. In this review we used mammalian pyruvate kinase (PK) as a model system to understand the role of protein dynamics in modulating cooperativity. PK has a triosephosphate isomerase (TIM)(α/β)8 barrel structural motif. PK is an ideal system to address basic questions regarding regulatory mechanisms about this common (α/β)8 structural motif. The simplest model accounting for all of the solution thermodynamic and kinetic data on ligand-enzyme interactions involves two conformational states, inactive ET and active ER. These conformational states are represented by domain movements. Further studies provide the first evidence for a differential effect of ligand binding on the dynamics of the structural elements, not major secondary structural changes. These data are consistent with our model that allosteric regulation of PK is the consequence of perturbation of the distribution of an ensemble of states in which the inactive ET and active ER represent the two extreme end states. Sequence differences and ligands can modulate the distribution of states leading to alterations of functions. The future work includes: defining the network of functionally connected residues; elucidating the chemical principles governing the sequence differences which affect functions; and probing the nature of mutations on the stability of the secondary structural elements, which in turn modulate allostery.  相似文献   

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