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81.
为了对温室大棚室温实施监测、避免局部温度过高,利用多片DS18B20单总线型数字温度传感器,采用外部供电方式,结合AT89S52单片机,外加串口电路、报警电路以及显示模块,设计了多点温度测量并报警的硬件系统。依据DS18B20型温度传感器操作指令,首先读取各传感器的序列号,并确定传感器对应的各点位置关系,定时循环读出各个传感器的温度值并循环显示,单片机依据设定的报警温度上下限做出报警处理;同时,也可利用串口把各点的温度值传给上位机作进一步的处理。实例表明,该系统工作稳定,操作方便,成本低廉,实现了温室大棚中的多点温度检测以及越限报警功能,测温误差在±0.5oC以内。 相似文献
82.
农机安全监理担负着我国数以千万计的农业机械及其驾驶员的行政管理任务,相应的法律法规要求采用计算机管理系统来对此进行处理并能够及时地将有关信息传送到全国农机监理信息系统。由于全国统一的农机监理信息系统尚未建立,因此提出了构建全国农机监理信息系统数据库标准,即采用B/S模式进行应用程序开发,通过多种网络连接全国各地农机监理业务计算机,从而实现信息共享与网上办公的解决方案。 相似文献
83.
AIM To observe the effect of Fuzilizhong decoction on the inflammatory damage of non-alcoholic fatty liver disease (NAFLD) rats and to explore its mechanism. METHODS SPF male SD rats were randomly divided into 6 groups: control group, model group, high dose (20 mg·kg-1·d-1), middle dose (10 mg·kg-1·d-1), low dose (5 mg·kg-1·d-1) Fuzilizhong decoction group and Yishanfu (30 mg·kg-1·d-1)group, 8 rats in each group. A NAFLD rat modelwas established by intragastric administration of fat emulsion for 4 weeks. Then the drug was given for 4 weeks in each treatment group. HE staining was performed to observe the histopathological changes of the rat liver.The serum levels of interleukin-2(IL-2), IL-6 and tumor necrosis factor-α(TNF-α) were measured by ELISA. The expression of toll like receptor 4(TLR4) and NF-κB p65 in liver tissues at mRNA and protein levels was determined by RT-qPCR and Western bolt,respectively. RESULTS Compared with control group, the inflammatory damage of liver tissue was more serious, the serum levels of IL-2, IL-6 and TNF-α, the mRNA expression TLR4 and NF-κB p65 in liver tissues were significantly increased in model group(P <0.05). However, compared with model group, the liver pathological changes in each treatment group were significantly relieved, the serum levels of IL-2, IL-6 and TNF-α, the mRNA expression of TLR4 and NF-κB p65 in liver tissues were significantly reduced(P <0.05).In addition, the changes of TLR4 and p-NF-κB p65 protein levels in liver tissue were consistent with the changes of TLR4 and NF-κB p65 mRNA. CONCLUSION Fuzilizhong decoction attenuates the inflammatory damages of NAFLD in rats by inhibiting TLR4/NF-κB p65 signaling pathway. 相似文献
84.
85.
比久和多效唑混合物的高效液相色谱分析 总被引:3,自引:1,他引:3
在吸光度为210nm、流动相配比为甲醇:乙腈:水=40:20:40的条件下,多效唑和比久均能得到很好的分离。比久的保留时间约为3.19min,多效唑的保留时间约为11.83min。加标回收率:比久为108.69%,多效唑为90.39%。 相似文献
86.
《Communications in Soil Science and Plant Analysis》2012,43(11):1085-1091
Abstract Radlands Crimson strawberries were grown in a glasshouse with 7 rates of applied boron. Wood shavings mulches with different boron concentrations were also applied as separate treatments. Boron toxicity symptoms were produced in leaves by boron rates of 0.32 kg ha‐1 and greater on a soil containing 1.6 ug B g‐1 of hot water extractable boron. Concentrations greater than 123 μg B g‐1 in old leaves were associated with boron toxicity symptoms. In the B rate experiment, soil boron concentrations greater than 1.9 μg B g‐1 soil were associated with leaf toxicity symptoms which increased in severity with increasing soil boron concentrations up to 4.1 μg B g‐1 soil. Wood shavings mulch containing 17 μg B g‐1 caused boron toxicity symptoms in older leaves whereas mulches containing less than 6 μg B g‐1 did not produce toxicity symptoms. 相似文献
87.
An antagonistic rhizobacterium, Pseudomonas jessenii EC-S101, isolated from the rhizosphere of spinach, produces two related secondary metabolites, 3-[(1 R )-hydroxyoctyl]-5-methylene-2(5 H )-furanone (4,5-didehydroacaterin) (1) and 3-[(1 R )-hydroxyhexyl]-5-methylene-2(5 H )-furanone (2). This study demonstrated their in vitro inhibitory effects, in particular those of (1), against Aphanomyces cochlioides AC-5 and Pythium aphanidermatum PA-5. The compounds inhibited radial growth and induced morphological abnormalities characterized by hyperbranching and periodic swelling in AC-5 and PA-5 hyphae, respectively. Staining with rhodamine-phalloidin, which binds to plasma-membrane-associated filamentous-actin (F-actin), revealed that tip-specific actin filaments were remodelled into a plaque-like form at an early stage of encounter (up to 24 h) with (1) or (2), whereas at later stages of encounter (48 h), the plaques were eliminated, reflecting the disorganization of actin arrays in the morphologically abnormal AC-5 and PA-5 hyphae. A similar response of actin disorganization was observed in AC-5 and PA-5 hyphae upon treatment with latrunculin B (3), an actin-assembly inhibitor produced by a sea sponge. It is suggested that (1) and (2) caused actin disorganization and their inhibitory activities were comparable to that of (3). Further ultrastructural observations substantiated abnormal functioning and delocalization of F-actin-linked cell organelles. 相似文献
88.
D—1菌株系从自然死亡的灯蛾虫尸分离的一株苏云金杆菌新菌株。经菌种鉴定与Bt.var.kurstaki相同,属血清Ⅲ型。其培养特性表现为:对培养基成分和培养温度适应范围较小,在温度28-30℃,培养基含固量为4.1-6.7%,C/N为5.7-6.2时发酵正常。32℃以上和浓培养基则影响其正常繁殖。这与HD-1菌株相吻合。对菜青虫、棉铃虫、玉米螟和松毛虫等4种昆虫毒力测定结果表明,D—1菌兼有H_5型青虫菌81—6和H_3型HD-1的杀虫特性。它对菜青虫和松毛虫的毒力与81—6相接近而高出HD—12.7—5.1倍。对棉铃虫和玉米螟的毒力则明显高于81—6也比HD—1强。 相似文献
89.
松褐天牛引诱试验初报 总被引:15,自引:0,他引:15
松材线虫病[Bursaphelenchus xylophilus(Steiner and Bubrer,1934)Nickle 1970]自1982年在我国南京中山陵发现以来,现已扩散至南京、镇江两市的12个区(县),安徽省马鞍山市、和县及滁县的部分松林。同时,在深圳马尾松林也发现了松材线虫为害(由香港疫区蔓延而来)。松褐天牛Monochamus alternatus Hope为该病的传播媒介。 相似文献
90.
猪肺炎支原体与猪支气管败血波氏杆菌在猪体液免疫和生长性能上的协同作用 总被引:1,自引:0,他引:1
试验选用10日龄成华×大约克杂交猪36头,随机分成四组(1、2、3、4),每组9头.其中1、2组用猪肺炎支原体全菌抗原免疫后再分别用猪肺炎支原体和猪支气管败血波氏杆菌进行攻毒,3、4组注射生理盐水作为对照,并与前两组同时分别用猪肺炎支原体和猪支气管败血波氏杆菌进行攻毒.采用间接ELISA、组织切片等方法对猪血清中的抗体水平、肺脏的病理变化及生长性能进行测定.试验表明:用猪肺炎支原体全菌抗原接种猪后,在血清中能检测到较高的抗体水平(25).猪肺炎支原体攻毒后2周,免疫猪和对照猪血清中猪肺炎支原体抗体的滴度分别为23.8与22.4(P<0.05),且免疫猪的生长性能比对照猪好.在猪支气管败血波氏杆菌攻毒组,攻毒2周和4周后免疫猪血清中的猪支气管败血波氏杆菌抗体水平与对照猪相比分别提高了26.67%和30.00%(P>0.05),6周后免疫猪和对照猪血清中的猪支气管败血波氏杆菌抗体分别为21.7和20.3(P<0.05),且在攻毒后4~6周,免疫猪的生长性能有了显著的改善.组织切片显示,无论是用猪肺炎支原体攻毒还是用猪支气管败血波氏杆菌攻毒,免疫猪的肺脏病变程度都较对照猪轻. 相似文献