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221.
本文报道了植物生长素Q.C.对海带苗的影响试验。结果表明,Q.C.对海带苗的细胞分裂具有明显的促进作用,从而加速了海带配子体的生长发育。其中以0.2×10^-^6(V/V)组的效果最明显,经处理3d后配子体大小达18-20μm,11d后达20-23μm,并已进入了性成熟期,♀体一级突起达22%,而对照组的大小为16-18μm,一级突起仅1%,用Q.C.处理配子体阶段转化而成的幼孢子体或幼孢子体阶段 相似文献
222.
The unknown aetiology of Chronic Kidney Disease (CKD) has attracted recent attention as a result of the increasing global prevalence and recent reviews of occupational and environmental exposure to nephrotoxins. The main focus of this research is to examine the potential relationship between environmental exposure to known nephrotoxins including arsenic, cadmium and lead and the potential health risk associated with the progressive dysfunction of the kidneys in renal impaired patients with CKD across Northern Ireland. In addition to these known nephrotoxins, co-abundance with several essential elements has been found to play a role as protecting mechanisms while others increase the uptake of nephrotoxic elements as a result of similar absorption mechanisms within the body. Key elements protecting the body from toxicity include selenium and zinc, whereas those which have been attributed to enhance the uptake of arsenic, cadmium and lead include iron and calcium. The compositional nature of the soil and stream geochemical data is explored to aid in the analysis of interactions between elements. Two approaches, one data-driven and the other knowledge-driven, are explored to investigate the associations between co-abundant elements. The bioaccessibility of these elements, which is the portion of the relevant toxin absorbed within the body, is also investigated to identify areas across Northern Ireland with an increased environmental hazard and potential health risk. The study uses a combination of datasets from the United Kingdom Renal Registry (UKRR) unknown aetiology subset, the soil and stream geochemical dataset from the Tellus Survey (GSNI) with the addition of a bioaccessibility subset. Findings suggest a relationship between the presence of elevated arsenic in stream waters and impaired renal function of the kidneys. Interactions between essential elements and potentially toxic elements could explain the regional variation of CKD of uncertain aetiology across Northern Ireland. 相似文献
223.
BM Macey KW Christison J de Goede L Hutchings CD van der Lingen 《African Journal of Marine Science》2016,38(2):269-273
Catches of South African sardine Sardinops sagax have declined in recent years from about 200 000 t harvested annually during the period 2002–2006 to less than 100 000 t. Consequently, some companies are now importing sardine from sources elsewhere in the world to meet local demand for canned sardine and bait. This importation has the potential for the introduction of sardine pathogens, in particular the pilchard herpesvirus (PHV), which could have a negative impact on the currently small South African sardine population. The aims of the current study were to determine whether PHV is present in the local sardine population and to assess the extent to which sardine is being imported into the country and whether imported fish are from countries where the virus is known to be endemic. Fish sampled from South Africa’s western (n = 150), southern (n = 182) and eastern (n = 96) putative stocks of S. sagax were analysed for the presence of PHV using real-time quantitative polymerase chain reaction (qPCR). The origin and amount of potentially infected material imported into South Africa during the period 2010–2014 was also assessed. None of the South African sardine collected during this study tested positive for PHV, suggesting that active PHV was not prevalent in the local population of S. sagax at the time of this study. Between 56 000 and 71 000 t of frozen sardine was imported annually into South Africa from countries where S. sagax occurs, including some from areas (Australia and New Zealand) where sardine infection by PHV is known to be endemic. Hence, it is plausible that the PHV pathogen, capable of perpetuating infections in local sardine populations, could be imported into South Africa along with the importation of frozen sardine. Should local sardine be naïve to the virus, as suggested by this study, then the population is at risk of infection and precautions against such must be taken. 相似文献
224.
闽粤地区鲍暴发性流行病的病因分析和流行病学研究 总被引:5,自引:1,他引:4
1999年以来,福建、广东两省养殖鲍已连续多年发生了暴发性流行病,死亡率可达100%。结合病理学分析与流行病学调查结果分析,认为球状病毒和弧茵并发感染是该暴发病流行的主要原因。电镜观察发现病鲍的肝细胞和肠上皮细胞内有大小约为130~150nm和50-70nm的2种球状病毒,前者数量较多,具外囊膜,后者的病毒颗粒裸露,未见外囊膜。感染造成了鲍的肝脏和肠等器官的细胞结构严重破坏。人工感染实验表明注射、混朱浸泡等方式均会昔擞感染。根据回归实验和流行特.最调查,结合胡疆巴湫果,该病多发生于23℃以下的水温期,主要是通过海水的流动和养殖水的交换和鲍的运销而传播,25℃以上水温未见该病暴发。 相似文献
225.
226.
目的:探讨麻杏苡甘汤加味治疗新型冠状病毒肺炎(COVID-19)的分子靶标及可能的机制。方法:从TCMSP以及BATMAN-TCM数据库中按照一定规定方法挑选出麻杏苡甘汤加味的活性成分及主要分子靶标。从OMIM及GeneCards中获得COVID-19的靶点。利用Bioinformatics & Evolutionary Genomics平台获得麻杏苡甘汤加味-COVID-19的共同靶点,然后将共同目标靶点导入STRING数据库,获得蛋白质网络模型,构建“有效成分-靶标”网络,并对共同目标靶点进行GO富集分析和KEGG富集分析。结果:麻杏苡甘汤加味中有118个活性成分可能通过46个靶点发挥抗COVID-19作用,GO富集分析及KEGG富集分析显示麻杏苡甘汤加味在治疗COVID-19的过程中,主要是通过影响脂多糖、细菌源分子、金属离子作用于氧化应激、凋亡信号通路等生物过程。方中的有效活性物质主要通过AGE-RAGE、肿瘤坏死因子(TNF)、白细胞介素(IL)-17等信号通路,影响细胞因子与配体的有效结合、磷酸酶的生成、血红素集合等有关。结论:麻杏苡甘汤加味中有118种成分具有抗COVID-19的作用,这些分子可能的作用机制为影响血管通透性及凝血组织因子基因的表达、抗病毒、抗炎,从而缓解新冠病毒所致的肺损伤以及凝血功能障碍、微小血栓形成等。 相似文献
227.
228.
大骨节病是一种影响因素复杂、病因一直未明的地方病,其学说众多。本文阐明了中国大骨节病地域分布与病情动态变化特征,重点论述了中国大骨节病自然环境与地质环境特征以及病因研究现状。针对多种病因学说,本文认为大骨节病病因是多因素复合作用的结果,硒缺乏是环境背景因素、环境中与人体有关的毒素是主控因素、常量与微量因素的比例失调是影响因素。病因研究中应注意宏观与微观相结合、地学与医学等多学科相结合。 相似文献
229.
【目的】探讨高蛋白酵母培养物替代鱼粉对凡纳滨对虾(Litopenaeusvannamei)生长性能、血清生化指标、非特异性免疫力和抗病力的影响。【方法】在基础饲料中分别添加质量分数0、2.5%、5.0%和7.5%酵母培养物(记为Y0、Y2.5、Y5.0和Y7.5组),分别替代质量分数0、10%、20%和30%的鱼粉,配制4种等氮等脂饲料,饲喂凡纳滨对虾(初始体质量0.70±0.03 g)56 d后,测定对虾生长性能、血清生化及免疫酶指标;用哈维氏弧菌(Vibrioharveyi)攻毒,测定对虾累计死亡率。【结果】Y2.5和Y5.0组凡纳滨对虾增重率和特定生长率与Y0组的差异无统计学意义(P> 0.05),Y5.0组凡纳滨对虾摄食率显著高于Y0和Y2.5组(P <0.05);Y5.0组凡纳滨对虾血清甘油三酯含量显著低于Y0组(P<0.05),Y7.5组凡纳滨对虾血清谷丙转氨酶含量显著高于Y0、Y2.5组(P <0.05),血清总胆固醇显著低于Y0、Y2.5组(P <0.05);酵母培养物替代饲料中20%和30%的鱼粉可显著提高对虾攻毒前肝胰腺超氧化物歧化酶、过氧化物酶活性(P <0.05),Y7.5组对虾肝胰腺丙二醛含量在哈维氏弧菌(Vibrio harveyi)攻毒后显著低于Y0组(P <0.05);攻毒7 d后,Y7.5组凡纳滨对虾累积死亡率显著低于Y0组(P<0.05)。【结论】酵母培养物替代鱼粉比例小于20%时,不会显著影响凡纳滨对虾生长性能;替代比例为30%时,生长受抑制。当替代量比例为30%时可显著提高凡纳滨对虾非特异性免疫力和抗病力。 相似文献
230.
目的: 评价风湿性心脏瓣膜病置换前320排容积CT心脏冠状动脉增强扫描的和临床应用价值。方法: 35例风湿性心脏病瓣膜病患者术前320排容积CT冠状动脉增强扫描,分析其伴发冠心病的原因及其冠状动脉发生狭窄的部位及程度,初步评价320排容积CT扫描冠状动脉血管增强的临床应用价值及优势。结果: 385支冠状动脉中显示,364支未见异常,有11支冠状动脉狭窄大于50%为阳性,另10支冠状动脉狭窄小于15%~30%,提示临床有轻度粥样硬化改变。结论: 风湿性心脏瓣膜病瓣膜置换前,50岁以上患者无论有无冠心病的危险因素,均应常规行320排容积CT冠状动脉增强扫查,以减少置换术的并发症,确保瓣膜置换术后复跳的成功。 相似文献