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991.
Comparison of immune responses and antioxidant status of different generations of growth‐selected Portunus trituberculatus families 下载免费PDF全文
The purpose of this study was to investigate the effects of inbreeding on the immune responses and antioxidant status of Portunus trituberculatus juveniles. Results showed that inbreeding affected the total haemocyte count, and phagocytic, pro‐phenoloxidase (propo), phenoloxidase and antibacterial activities decreased after the seventh generation. Antioxidant status showed a similar pattern: total antioxidant capacity, superoxide dismutase (SOD) activity and GSH/GSSG in the cell‐free haemolymph and hepatopancreas decreased, while catalase activity in the cell‐free haemolymph increased (P < 0.05). There were no significant differences in α2‐macroglobulin and bacteriolytic activities in the cell‐free haemolymph and glutathione peroxidase activity in the cell‐free haemolymph and hepatopancreas among nine inbreeding generations. Gene expression levels of proPO and crustin in haemocytes and SOD in haemocytes and hepatopancreas also decreased significantly as the inbreeding generations increased. The results suggest that a high level of inbreeding could severely reduce the physiological health of P. trituberculatus. Our obtained data would be particularly useful for P. trituberculatus breeding programmes. 相似文献
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993.
ABSTRACT: The effects caused by suspended particles in seawater and sediment cover of the substrate on the attachment to the substrate of zoospores, and on the subsequent growth and survival of gametophytes of the brown alga Eisenia bicyclis were examined in the laboratory. The attachment rate to the substrate of the zoospores was remarkably reduced by the sediment cover on the substrate, and it decreased to 3.8% of the no-sediment control by a slight sediment cover of 3.0 mg/cm2 (0.048 mm in thickness). The growth of gametophytes was not inhibited at 10 mg/cm2 or less of sediment cover, though it was stopped at 30 mg/cm2 . The survival rate of gametophytes became 39.4% at 5 mg/cm2 on the substrate, and gametophytes were all blighted at 30 mg/cm2 . The ratio of male to female of the surviving gametophytes became 81.5:18.5, when the sediment cover was 10 mg/cm2 . The rate of total loss ( TL [%]) of zoospores and gametophytes of Eisenia bicyclis was obtained from the following equation: TL = 100 (1 − exp[−0.0339 C ] exp[−1.24 Q ]), where, C (mg/L) and Q (mg/cm2 ) indicate the concentration of suspended particles in seawater and the sediment on the substrate, respectively. 相似文献
994.
海参加工业是我国北方重要的水产品加工行业之一。近年来,随着市场需求的不断增大,海参加工产品产量逐年增加,海参加工业面临的环境问题日益凸显。为了促进我国海参加工业的清洁生产,保证产业的可持续发展,本研究基于我国清洁生产技术体系及海参加工行业的特点,构建了由生产工艺及装备等6个一级指标和加工工艺等24个二级指标组成的海参加工业清洁生产评价指标体系,并选择两家案例企业进行清洁生产水平的评价。研究结果表明,案例企业的清洁生产水平均为Ⅱ级:国内清洁生产先进水平;通过案例分析结果与企业生产现状的对比,证明本指标体系具有一定的科学性、可操作性和适用性。根据评价结果对两家案例企业提出了改变能源类型、提高废弃物资源利用率的清洁生产改进措施,为我国水产品加工行业的清洁生产提供了借鉴与参考。 相似文献
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Amy M. Schwartz Manjunath B. Shankar Kiersten J. Kugeler Ryan J. Max Alison F. Hinckley Martin I. Meltzer Christina A. Nelson 《Zoonoses and public health》2020,67(4):407-415
An estimated 300,000 cases of Lyme disease occur in the United States annually. Disseminated Lyme disease may result in carditis, arthritis, facial palsy or meningitis, sometimes requiring hospitalization. We describe the epidemiology and cost of Lyme disease‐related hospitalizations. We analysed 2005–2014 data from the Truven Health Analytics MarketScan Commercial Claims and Encounters Databases to identify inpatient records associated with Lyme disease based on International Classification of Diseases, Ninth Revision, Clinical Modification (ICD‐9‐CM) codes. We estimated the annual number and median cost of Lyme disease‐related hospitalizations in the United States in persons under 65 years of age. Costs were adjusted to reflect 2016 dollars. Of 20,983,165 admission records contained in the inpatient databases during the study period, 2,823 (0.01%) met inclusion criteria for Lyme disease‐related hospitalizations. Over half of the identified records contained an ICD‐9‐CM code for meningitis (n = 614), carditis (n = 429), facial palsy (n = 400) or arthritis (n = 377). Nearly 60% of hospitalized patients were male. The median cost per Lyme disease‐related hospitalization was $11,688 (range: $140–$323,613). The manifestation with the highest median cost per stay was carditis ($17,461), followed by meningitis ($15,177), arthritis ($13,012) and facial palsy ($10,491). Median cost was highest among the 15‐ to 19‐year‐old age group ($12,991). Admissions occurring in January had the highest median cost ($13,777) for all study years. Based on extrapolation to the U.S. population, we estimate that 2,196 Lyme disease‐related hospitalizations in persons under 65 years of age occur annually with an estimated annual cost of $25,826,237. Lyme disease is usually treated in an outpatient setting; however, some patients with Lyme disease require hospitalization, underscoring the need for effective prevention methods to mitigate these serious cases. Information from this analysis can aid economic evaluations of interventions that prevent infection and advances in disease detection. 相似文献
998.
膜下滴灌技术的大面积推广和应用,为新疆乃至西北干旱地区作物高产提供了强大的技术支撑。应用在盐碱地改良中,膜下滴灌“有灌无排”模式仅调节耕层盐分分布,并不能将盐分排出土体,长年灌溉容易引起爆发式积盐的风险,而暗管排水是目前公认的改良盐碱地最直接、最有效的方法。目前,将膜下滴灌与暗管排水有机结合形成的新型灌溉技术,充分利用膜下滴灌良好的抑蒸增温、节水抑盐等优势,同时利用暗管将淋洗盐水及时排出土体,使盐碱化土层产生新的水盐平衡,已在新疆盐碱地区开发利用中得到长足发展。本文重点分析并总结了新疆灌区膜下滴灌结合暗管排水系统的设计参数及土壤水盐运移规律,并综述了土壤理化性质及作物产量对该灌排技术的响应研究,以期为新疆盐碱地农业可持续发展提供理论依据和技术指导。 相似文献
999.
1000.
金银花叶片绿原酸提取及工艺参数优化的研究 总被引:3,自引:0,他引:3
金银花叶片绿原酸含量仅次于花,通过醇法、超声波法、酶法3种不同方法提取单因素试验和正交试验,结果表明:提取效率酶法优于超声波法,超声波法优于醇法。醇法回流提取的最佳条件是温度90℃,φ=80%乙醇浓度,pH4.0,回流时间2 h,料液比1∶10;超声波法提取的最佳条件是温度50℃,φ=60%的乙醇浓度,pH4.0,超声波功率100 W,料液比1∶8;酶法提取最佳条件是26℃,20 g/L纤维素酶、10 g/L果胶酶,pH4.0,提取4 h,料液比1∶20。粗提取物对革兰氏阴性菌和革兰氏阳性菌均有抑菌和杀菌活性。 相似文献