The Effect of Arbutin on Mice Brain Cells after Ischemia-reperfusion Injury

[Objective]To study the effect of the Chinese traditional medicine arbutin on brain cells after ischemia-reperfusion injury and provide a theoretical foundation for its clinical application. [Methods]Forty Kunming mice were randomly divided into four groups,namely the blank group,the ischemia-reperfusion group,the chemoprophylaxis group and the medication group. The cerebral ischemia-reprefusion model,made according to the principle of brain damage caused by ischemia,was stained with TTC and HE to observe cells' morphological changes.SOD activity,MDA content and GSH-Px activity in brain tissues were tested. [Results]Compared with the ischemia-reperfusion group,necrosis of ischemia areas stained by TTC in the chemoprophylaxis group and the medication group was less obvious. HE staining showed the alleviation of cells damage. The enhancement of SOD activity and that of GSH-Px activity showed significant differences. MDA content was reduced(P 0.05 for both). [Conclusions]Arbutin had antioxidant properties which can effectively prevent and protect brain cells from damage.     

Protective Effects of Coriolus versciclor Polysaccharides on Liver Injury of Mice Induced by CCl_4

[Objective] To discuss the protective effects of Coriolus versciclor polysaccharides on liver injury of mice induced by CCl4.[Methods]40 male Kunming mice at four moths old were randomly divided into four groups,which were control group,model group,C. versciclor polysaccharides protection group and feeds + C. versciclor polysaccharides group. Mice were fed for 8 d. On 2 h after final administration,intraperitoneal injection of blend oil solution was carried out was carried out in control group. And in other groups,intraperitoneal injection of0. 15% CCl4 blend oil solution( 10 mL / kg) was conducted. After 18 h,eyeballs were collected and serum was isolated. Livers were taken out and the hepatosomatic index was calculated. Liver homogenate was prepared and the ALT and AST were detected,as well as the SOD and NOS activities,and MDA,GSH and NO contents.[Results] Compared with model group,C. versciclor polysaccharides in different administration ways reduced the hepatosomatic index( P 0. 05) and MDA content( P 0. 001),lowered the AST activity in serum( P 0. 05),the NOS activity and the NO content( P 0. 01),and enhanced the SOD activity and GSH content( P 0. 01).[Conclusions] C. versciclor polysaccharides in different administration ways protected the liver injury of mice induced by CCl4.     

金樱子多糖对小鼠急性药物肝损伤的保护作用

为探讨金樱子多糖对CCl4所致小鼠急性肝损伤的保护作用。建立CCl4诱导的小鼠急性肝损伤模型,分光光度法检测丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、碱性磷酸酶(ALP)、丙二醛(MDA)和还原型谷胱甘肽(GSH)含量,以及超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH2Px)的活性。结果表明：高剂量的金樱子多糖可显著降低CCl4所致急性肝损伤小鼠的肝脏指数(P<0.05)和脾脏指数(P<0.01);中、高剂量的金樱子多糖可显著降低CCl4所致急性肝损伤小鼠血清ALT、AST、ALP活性(P<0.01)和肝组织MDA含量(P<0.01),提高肝组织ALT、AST、ALP活性(P<0.01)和GSH-Px、SOD活性（P<0.01或P<0.05）,并增加GSH的含量(P<0.01)。金樱子多糖对CCl4所致小鼠急性肝损伤具有一定的保护作用。     

Preventive Effects of Vitamin C And Polysaccharides in Dioscrea pposite Thunb. on Cadmium-induced Liver Injury in Mice

[Objective]To investigate the preventive protective effects and its mechanism of vitamin C and polysaccharide in Dioscrea pposite Thunb. on cadmium-induced liver damage in mice. [Methods]50 Kunming mice were randomly divided into control group,model group,D. pposite polysaccharides protection group,vitamin C protection group,D. pposite polysaccharides and vitamin C protection group. At the 7th day of feeding,the mice were given saline by gavage,and the mice in other groups were intraperitoneally injected with 3. 0 mg /kg CdCl2 solution. 24 hours after injection,blood was collected for ALT and AST test. Then,mice were sacrificed and the livers were removed for the calculation of hepatosomatic index(liver weight / body weight). Also,the liver homogenates were prepared for the determination of SOD and GSHPx activities and the of MDA and NO contents. [Results]Compared with the mice in model group,the liver-somatic index,serum ALT,AST activity,and contents of liver MDA and NO reduced,the activities of SOD and GSH-Px,and the content of GSH improved in D. pposite polysaccharides and vitamin C protection group(*P 0. 05,**P 0. 01). Compared with the model grfoup,the protective effects of D. pposite polysaccharides combined with vitamin C strengthened(**P 0. 01). [Conclusions]The combination of D. pposite polysaccharides and vitamin C has preventive protection effects on cadmium-induced liver injury in mice by antagonizing cadmium and /or oxidative stress. The application of D. pposite polysaccharides combined with vitamin C had a synergistic effect.     

急、慢性冷应激对雏鸡腓肠肌及血清抗氧化功能的影响

【目的】探讨自由基在冷应激对禽类机体损伤中所起的作用,为探索促进动物冷适应的方法,提高动物的抗寒能力提供一定的理论依据;【方法】应用化学比色法检测了急、慢性冷应激对腓肠肌和血清中总抗氧化能力(T-AOC)、过氧化氢酶(CAT)活性、谷胱甘肽过氧化物酶(GSH-Px)活性、超氧化物歧化酶(SOD)活性及丙二醛(MDA)含量的影响;【结果】急性应激时,随应激时间的延长,腓肠肌T-AOC与SOD活性均逐渐降低,GSH-Px活性、CAT活性及MDA含量均逐渐升高,血清T-AOC逐渐降低,GSH-Px活性、CAT活性、SOD活性及MDA含量均逐渐升高;慢性应激时,随应激时间的延长,腓肠肌T-AOC、GSH-Px活性、CAT活性及SOD活性均逐渐升高,MDA含量逐渐降低,血清T-AOC、GSH-Px活性、CAT活性及MDA含量均逐渐升高,SOD活性逐渐降低;【结论】表明急、慢性冷应激均可使机体的抗氧化功能发生改变,诱发氧化胁迫,导致机体内自由基增多,对机体造成损伤。     

小分子胶原多肽的抗氧化活性研究

为了研究小分子胶原多肽清除DPPH?自由基、羟自由基(-OH)的能力和抗氧化的能力。采用体外DPPH?自由基和羟自由基(-OH)清除系统测定小分子胶原多肽清除自由基的能力;建立D-半乳糖致衰老的模型小鼠,测定小鼠血液及肝脏组织内的超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活力和丙二醛(MDA)含量。结果表明,1000 kDa以下胶原多肽(CP1)组分在10 mg/mL浓度时,对DPPH?自由基的清除率为80%;40 mg/mL时对-OH的清除率为91.56%。与模型组相比服用CP1的小鼠血清和肝脏丙二醛(MDA)含量显著降低(P＜0.01);超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活力显著升高(P＜0.05)。表明小分子胶原多肽具有显著的抗氧化作用。     

小花棘豆黄酮对小鼠抗衰老作用的研究

为探讨新疆小花棘豆黄酮对衰老模型小鼠的抗衰老作用。用D-半乳糖制备衰老小鼠模型,然后分别以100、200、300 mg/(kg·d)剂量的小花棘豆黄酮灌胃,观察其对血清、肝脏和脑组织中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)的活性及丙二醛(MDA)和脂褐素(LPO)含量,以及对小鼠缺氧存活时间及游泳时间的影响。结果表明：小花棘豆黄酮能不同程度增加血清和组织中SOD、GSH-Px、CAT的活力,极显著降低MDA和LPO含量。高剂量的小花棘豆黄酮还能极显著延长小鼠在缺氧条件下的存活时间和常温游泳时间。小花棘豆黄酮具有较好的抗衰老作用。     

Effect of MORINDAE OFFICINALIS Extract on the Behavior and Zymology of Senile Dementia Model Rats

[Objective]To study the effect of MORINDAE OFFICINALIS extract on the behavior and zymology of senile dementia rat model. [Methods]Senile dementia rat model was prepared by intraperitoneal injection of D-galactose( 120 mg/kg) and sodium nitrite( 90 mg/kg) for 30 d. 60 rats were divided into 6 groups,normal control group,model group,nimodipine group,high-dosage group of aqueous extract of MORINDAE OFFICINALIS,medium-dosage group of aqueous extract of MORINDAE OFFICINALIS and low-dosage of aqueous extract of MORINDAE OFFICINALIS. The learning and memory ability was measured by rat step-down test. The activities of SOD,MDA and MAO-B were determined. The expression of MAO-B mRNA was determined by RT-PCR. [Results]After intraperitoneal injection of MORINDAE OFFICINALIS extract,the learning and memory abilities of model rats increased. The biochemical criterion of SOD,MDA and MAO-B was improved. The expression level of MAO-B mRNA decreased significantly. [Conclusions] Extract of MORINDAE OFFICINALIS could protect acute aging model rats at certain degree.     

富硒与富锗桦褐孔菌多酚的体内外抗氧化作用

研究桦褐孔菌多酚(IOP)以及富硒培养的桦褐孔菌多酚(Se-IOP)、富锗培养的桦褐孔菌多酚(Ge-IOP)的抗氧化作用。以试剂盒法测定抗活性氧单位、MDA值,分光光度法测定脂肪氧合酶活力、红细胞溶血抑制率、谷胱甘肽过氧化物酶活力。在化学模拟体系中,4.0 mg/mL的IOP、Se-IOP与Ge-IOP的抗氧化活性单位分别为52.36、89.21、82.93 U/mL,对脂肪氧合酶活性的抑制率分别为34.15%、42.22%、50.53%。在细胞与组织水平的体外抗氧化体系中,4.0 mg/mL IOP对H2O2诱导的小鼠红细胞溶血抑制率为69.65%,而1~4.0 mg/mL Se-IOP与Ge-IOP溶血抑制率均大于100%;与对照组比较,1~4.0 mg/mL IOP、Se-IOP与Ge-IOP均可极显著地抑制小鼠肝匀浆自发性产生MDA(P<0.01)。个体水平的体内抗氧化体系中,腹腔注射IOP、 Se-IOP与Ge-IOP(4.0 mg/mL,0.5 mL/d,12天)时,肝组织的自发性MDA指标均极显著下降(P<0.01);腹腔注射1~4.0 mg/mL Se-IOP与Ge-IOP后,各剂量组小鼠血清与肝匀浆谷胱甘肽过氧化物酶GSH－PX活力均极显著增强(P<0.01)。IOP、Se-IOP与Ge-IOP在体内外均具有明显的抗氧化作用,富硒、富锗可增强桦褐孔菌多酚的抗氧化能力。     

蜂蛹黄酮对四氧嘧啶致亚急性衰老小鼠体内几种抗氧化酶活性的影响

研究了蜂蛹黄酮对四氧嘧啶致亚急性衰老小鼠体内几种抗氧化酶活性的影响。结果表明,蜂蛹黄酮能够有效抑制四氧嘧啶导致的小鼠血液、肝脏和脑组织的SOD,GSH-PX,CAT和MAO活性的升高,降低血液、肝脏和脑组织中LPO的浓度。表明蜂蛹黄酮具有很好的清除自由基作用,对小鼠的血液、肝脏和脑组织具有保护作用。     

自制有机碘栓对獭兔子宫内膜炎治疗研究

研究自制有机碘栓对獭兔子宫内膜炎治疗效果。通过子宫灌注致病性大肠杆菌、葡萄球菌、链球菌、沙门氏菌、蜡状芽孢杆菌等混合菌液,复制獭兔子宫内膜炎病理模型。分别于1天,3天,5天按0.01g/kg体重(按有效碘计算)子宫投放有机碘栓进行治疗,观察其用药前后的临床症状、子宫形态、子宫内膜病理学变化,并测定血清SOD,MDA,GSH-Px等生化指标。投药后第4天阴门肿胀及阴道充血逐渐消退,子宫分泌物逐渐减少;子宫颈和子宫角轻微肿胀,宫腔内有少量透明分泌物;子宫内膜较完整,上皮细胞结构基本正常。治疗组在第4天血清SOD和GSH-Px活力均高于病理对照组,差异显著(P0.05);第6天血清SOD活力高于病理对照组,差异显著(P0.05),而血清GSH-Px活力高于病理对照组,差异极显著(P0.01),血清MDA含量低于病理对照组,差异极显著(P0.01)。有机碘栓可有效治疗獭兔子宫内膜炎。     

RT-PCR法检测非酒精性脂肪肝细胞中CYP2E1基因的表达与普洱茶（熟茶）、铁观音、红茶的关系

探讨普洱茶（熟茶）、铁观音、红茶对高脂饮食诱发的大鼠非酒精性脂肪肝中P450 2E1基因表达的影响。将Wistar大鼠随机分为正常对照组、高脂模型组、药物组以及（低、中、高剂量）普洱茶（熟茶）、铁观音、红茶组[0.5、1.0、2.0 g/（kg·bw）]。试验大鼠灌胃授试茶样水浸提物35天后采血牺牲,分离血清测定抗氧化指标丙二醛（MDA）、谷胱甘肽（GSH-Px）和超氧化物歧化酶（SOD）的活性;采摘肝脏并进行肝脏病理检测;用RT-PCR检测试验大鼠肝脏细胞中P450 2E1的表达量。与高脂模型组相比,（低剂量组）普洱茶（熟茶）降低MDA效果显著（P〈0.05）;普洱茶（熟茶）、红茶和铁观音组中GSH-Px酶活力、SOD酶活性显著提高;（高剂量）普洱茶（熟茶）、红茶显著降低P450 2E1表达量（P〈0.05）;通过试验大鼠病理检测发现,普洱茶（熟茶）和（高剂量组）铁观音能明显改善由高脂饮食引起的肝脏脂肪病变。普洱茶（熟茶）、铁观音、红茶对P450 2E1在非酒精性脂肪肝中的基因表达具有不同程度的积极作用,但普洱茶（熟茶）的作用最显著。     

Pharmacodynamic Effects of Aquilaria sinensis Leaves and Its Comparison with LIGNUM AQUILARIAE RESINATUM in Pharmacological Actions

[Objective]To research the pharmacodynamic effects of Aquilaria sinensis leaves,and to compare pharmacological actions between A. sinensis leaves and LIGNUM AQUILARIAE RESINATUM. [Methods]Pharmacological experiments of analgesia,anti-inflammation,hypoglycemic action,relieving asthma and promoting intestine moving activity were carried out by whole animal tests. [Results] glucose values of diabetic mice induced by alloxan reduced significantly in LIGNUM AQUILARIAE RESINATUM group and high-dosage group of A. sinensis leaves( P 0. 05 or P 0. 01). Different dosage groups of A. sinensis leaves had extremely significant inhibitory effects on the auricle swelling of mice induced by xylene and the abdominal capillary permeability of mice induced by acetic acid( P 0. 01 or P 0. 05). Low- and middle-dosage groups of A. sinensis leaves and LIGNUM AQUILARIAE RESINATUM group had significant inhibitory effects on pains induced by thermal stimulus and acetic acid( P 0. 05 or P 0. 01),and obviously prolonged the asthma latency time of guinea pigs( P 0. 05);and high-dosage group of A. sinensis leaves also obviously prolonged the asthma latency time of guinea pigs( P 0. 05). Water extracts of A. sinensis leaves showed significant differences in time to falling asleep and sleeping time of mice( P 0. 01 or P 0. 05). Different dosage groups of A. sinensis leaves and LIGNUM AQUILARIAE RESINATUM group significantly enhanced the intestine moving distance and rate( P 0. 05,P 0. 01 or 0. 001). [Conclusions]Ethanol extracts from A. sinensis leaves and LIGNUM AQUILARIAE RESINATUM had certain functions ofanalgesia,anti-inflammation,hypoglycemic action,relieving asthma and promoting intestine moving activity. Effects of ethanol extracts from A. sinensis leaves were equal to the effects of LIGNUM AQUILARIAE RESINATUM; and the ethanol extracts from A. sinensis leaves was superior to LIGNUM AQUILARIAE RESINATUM in anti-asthma and promoting intestine moving activity.     

NaCl胁迫对银槭幼苗生长及部分生理特性的影响

为研究银槭幼苗的耐盐能力,以银槭的1年生播种苗为试材,对不同浓度NaCl胁迫下银槭的生物量、光合性能、叶绿素含量、可溶性糖含量、MDA含量、POD、SOD酶活性等进行了研究。结果表明：盐胁迫抑制了银槭的生长;使得叶绿素含量、光合性能降低;可溶性糖、MDA含量增加;POD、SOD活性呈先增加后下降趋势。通过对这些耐盐性生理指标的相关性分析和主成分分析,最终确定胞间CO2浓度、蒸腾速率和生物量可以作为银槭耐盐性评价的参考指标,并指出银槭的耐盐范围在0.4%以下。     

Anti-bacterial Effects in Vitro of Jinweng Zhili Granules and Its Antipyretic and Anti-inflammatory Effects on Animal

[Objective] To research the anti-bacterial effects in vitro of Jinweng Zhili Granules and its antipyretic and anti-inflammatory effects on animal. [Methods]Anti-bacterial effects of Jinweng Zhili Granules were detected by MIC method and drug sensitive test. A total of60 male Kunming mice were randomly divided into blank control group,aspirin group,low-dosage group of Jinweng Zhili Granules,middledosage group of Jinweng Zhili Granules,and high-dosage group of Jinweng Zhili Granules. Mice were given drugs by gavage for 7 d. Swelling degree of ear slice was calculated and the anti-inflammatory effects were analyzed. A total of 60 rabbits were randomly divided into high-dosage group of Jinweng Zhili Granules,middle-dosage group of Jinweng Zhili Granules,low-dosage group of Jinweng Zhili Granules,positive drug group,blank control group and model group. Endotoxin was administrated through the ear venous in order to establish febrile model. Effects of Jinweng Zhili Granules on the body temperature of febrile rabbits induced by endotoxin were analyzed. Blood was collected by heart blood collection method. When the plasma was separated,cA MP content in rabbits were detected. [Results] The MIC values to Escherichia coli,Staphylococcus aureus,Clostridium welchii,Salmonella typhimurium,Candida albicans were 3. 75,1. 875,15,7. 5 and 7. 5 mg / mL,respectively. The swelling degree of mice slice in model group reached 121. 7%. And the swelling degrees in high- and middle-dosage groups of Jinweng Zhili Granules were 55. 6% and 56. 2%,respectively,which had extremely significant differences with that of model group( P 0. 01).Jinweng Zhili Granules reduced the body temperature of febrile rabbits induced by endotoxin. The cA MP content in model group was 34. 13 pmol / mL; and the cA MP contents in high-and low-dosage groups were 24. 74 and 26. 61 pmol / mL,respectively,which had extremely significant differences compared with model group( P 0. 01). [Conclusions]Jinweng Zhili Granules had anti-bacteria,anti-inflammation and antipyretic effects.     

Experimental Study on the Antitussive,Apophlegmatic and Antiasthmatic Effect of Extract of Jianhua

[Objective]To explore the antitussive,apophlegmatic and antiasthmatic effect of extract of Jianhua. [Methods]The antitussive, apophlegmatic and antiasthmatic effect of extract of Jianhua was studied by animal models. Control group,low-dosage group of extract of Jianhua,medium-dosage group of extract of Jianhua,high-dosage group of extract of Jianhua and positive medication group were included in the experiment. [Results] Compared with control group,low,medium and high-dosage of aqueous extract and alcohol extract of Jianhua could significantly inhibit cough induced by stronger ammonia water( P 0. 05,P 0. 01); medium and high-dosage of aqueous extract and alcohol extract of Jianhua could significantly increase phenol red excretion in the respiratory tract of mice( P 0. 05,P 0. 01); high-dosage of aqueous extract and alcohol extract of Jianhua could significantly prolong the incubation of asthma in guinea pigs induced by citric acid( P 0. 05). [Conclusions]The extract of Jianhua had significant effect of relieving a cough,eliminating phlegm and relieving asthma.     

Hypoglycemic Effects of the n-Butanol Part of Sorbus tianschanica

[Objective] To extract and isolate the effective components from Sorbus tianschanica,and to research the hypoglycemic effects of n-Butanol part. [Methods]S. tianchanica was extracted by reflux extraction. After gradient elution,n-Butanol part was obtained. With diabetic mice induced by STZ as the model,blood glucose test was carried out. [Results]n-Butanol part in administration group had significant differences in hypoglycemic effects with that in model group(P 0. 05),showing that n-Butanol part had certain antidiabetic functions on diabetic mice induced by STZ. And the hypoglycemic effects showed a reducing trend as the administration dosage decreased,indicating that administration dosage had positive correlation with hypoglycemic effects. n-Butanol in different parts could reduce the blood glucose of diabetic mice in different degrees. And the blood glucose value in high-dosage group(8 g /kg) reduced greatly at 2 h after administration,having great differences with that in model group(P 0. 01). This showed that high dosage was helpful to the glucose tolerance of diseased mice,and could effectively protect against the rapid increase of blood glucose after meal. n-Butanol had no significant effects on the blood glucose of normal mice. However,the morality rates in high-and middle-dosage groups were both higher than that in low-dosage group; and the morality rate in administration group was lower than that in model group,showing that n-Butanol could promote the survival rate of diabetic mice. [Conclusions]S. tianchanica had certain effects of anti-diabetes.     

马齿苋多糖对小鼠的抗衰老作用

用D-半乳糖制备衰老小鼠模型,同时经灌胃100、200、400 mg/马齿苋多糖,观察其对血清中超氧化物歧化酶(SOD)活性、谷胱甘肽过氧化物酶(GSH-Px)活性、丙二醛(MDA)含量和对动物缺氧存活时间及游泳时间的影响。结果表明,马齿苋多糖能不同程度增加血清中SOD及GSH-Px活力,极显著降低MDA含量。此外,马齿苋多糖还能极显著延长小鼠在缺氧条件下的存活时间和常温游泳时间。说明马齿苋多糖具有明显的抗衰老作用。     

镉对鸡肝脏抗氧化系统功能以及中药四君子汤拮抗效应的影响研究

为探讨中药四君子汤对镉中毒鸡肝脏GSH-Px、SOD活性抑制的拮抗作用。选用60只100日龄海兰公鸡,随机平均分为3组,对照组常规饲养,加镉组常规饲养的同时,添加CdCl2 150 mg/kg,中药四君子汤加镉组常规饲养的同时,添加CdCl2 150 mg/kg,添加1％中药四君子汤。分笼常规饲养,试验期为60天,这样就建立了亚慢性镉中毒及中药四君子汤拮抗模型。试验结果显示：肝脏谷胱甘肽过氧化物酶(GSH-Px)活性为对照组、中药四君子汤加镉组至加镉组依次降低;肝脏超氧化物歧化酶(SOD)活性为对照组、中药四君子汤加镉组至加镉组依次降低;肝脏丙二醛(MDA)含量为对照组、中药四君子汤加镉组至加镉组依次升高。表明日粮中添加中药四君子汤后可有效地提高机体的抗氧化能力。     

牛磺酸对克氏原螯虾生长性能、非特异性免疫以及肝胰脏抗氧化能力的影响

为了探讨牛磺酸对克氏原螯虾(Procambarus clarkii)生长性能、非特异性免疫以及肝胰脏抗氧化能力的影响。以300只初始体重为(4.50±0.50) g的克氏原螯虾为对象,随机分成5组,分别投喂5种不同牛磺酸含量的等氮等能饲料,投喂4周后,测定各组生长指标、血液和肝胰脏的生化指标。实验结果表明,200、300 mg/kg组克氏原螯虾的增重率、出肉率,血清总蛋白(TP)、溶菌酶(LSZ)以及肝胰脏超氧化物歧化酶(SOD)和过氧化氢酶(CAT)的活性,均高于对照组,具有统计学意义(P<0.05);200、300 mg/kg组克氏原螯虾的血清谷丙转氨酶(GPT)和谷草转氨酶(GOT)的活性均低于对照组,具有统计学意义(P<0.05);其中300 mg/kg组克氏原螯虾的成活率和肝胰脏谷胱甘肽(GSH-Px)的活性高于对照组,饵料系数低于对照组,均具有统计学意义(P<0.05);而肝胰脏丙二醛(MDA)的含量在各组间差异不具有统计学意义。因此,在饲料中添加200~300 mg/kg的牛磺酸可以促进克氏原螯虾的生长,提高虾体的非特异性免疫力和肝胰脏抗氧化能力,增强虾体的抗病力。