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971.
柑橘是是广西的重要果树品种,在水果产业中占有重要地位。通过对广西柑橘业的现状剖析,从自然资源、品种资源、社会资源、季节、成本、质量、区位等方面提出广西发展柑橘的优势,并对这些优势的利用及实现措施进行探讨,将有利于做强做大广西的柑橘产业。 相似文献
972.
为开发一种可用于体内或体外沙门菌防控的噬菌体混合制剂,使用丝裂霉素C从不同血清型沙门菌中诱导并纯化获得沙门菌噬菌体,初步分析其裂解谱和理化条件适应性.为拓展噬菌体制剂的裂解谱并综合发挥温和噬菌体pP14及烈性噬菌体pSQC73的优势,制成噬菌体混合制剂并评价其体外杀菌抑菌效果.结果 表明:沙门菌噬菌体pP14可耐受50... 相似文献
973.
一、何为救生犬救生犬是指经过特殊训练的,不需要踪迹就能找到失踪者的犬。它能通过人的气味在无路可行的开阔地或在废墟中找到需要救援的人。救生犬在培训中要适应极高的地方,通过栅栏、挡板和梯子等障碍锻炼。救生犬能不受白天黑夜、气候条件的限制完成任务,也不会因为受到视觉和声觉刺激而中断搜寻。警报、火、烟和其他救援人员或高分贝噪音不会影响救生犬工作。救生犬对人友善,对人或动物没有攻击性。二、救生犬能做什么(一)地面搜寻搜寻链中的一头救生犬在50米宽的走廊地带搜寻,要比使用25名救生人员在同一地带搜寻快5倍。搜寻链可由5… 相似文献
974.
黄皮次生木质部导管分子观察研究 总被引:1,自引:0,他引:1
运用细胞图象分析系统及显微照相的方法对黄皮次生木质部导管分子进行了观察研究。在黄皮的次生木质部导管分子中存在着许多不同的样式,分别对其进行了描述,并从导管分子个体发育与系统发育的角度进行了讨论。 相似文献
975.
Wei Chen Kaixiong Ye Xiaoji Zhu Huihui Zhang Ranran Si Jianing Chen Zijun Chen Kaili Song Zhicheng Yu Bingnan Han 《Marine drugs》2022,20(1)
Actinomycins as clinical medicine have been extensively studied, while few investigations were conducted to discover the feasibility of actinomycins as antimicrobial natural dye contributing to the medical value of the functional fabrics. This study was focused on the application of actinomycin X2 (Ac.X2), a peptide pigment cultured from marine-derived Streptomyces cyaneofuscatus, in the dyeing and finishing of silk fabric. The dyeing potential of Ac.X2 with silk vs. cotton fabrics was assessed. As a result, the silk fabric exhibited greater uptake and color fastness with Ac.X2. Through Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and X-ray diffraction (XRD) analyses, some changes of chemical property for the dyed fabric and Ac.X2 were studied. The silk fabric dyed with Ac.X2 exhibited good UV protection ability. The antibacterial properties of dyed and finished silk were also evaluated, which exhibited over 90% antibacterial activity even after 20 washing cycles. In addition, the brine shrimp assay was conducted to evaluate the general toxicity of the tested fabric, and the results indicated that the dyed silk fabrics had a good biological safety property. 相似文献
976.
977.
肥料减施下玉米-大豆间作对作物产量和昆虫群落组成及多样性的影响 总被引:1,自引:0,他引:1
为探究肥料减施下玉米-大豆间作对作物产量和昆虫群落组成及多样性的影响,在玉米、大豆单作及二者间作下施以标准肥料750 kg/hm~2和减半肥料375 kg/hm~2,于作物生长期调查田间昆虫群落组成及多样性,并在收获期对玉米和大豆进行测产。结果表明:与单作玉米相比,间作玉米在施用标准肥料下的百株生物量、百株籽粒重和千粒重分别显著增加78.33%、85.35%和38.71%,而在施用减半肥料下则分别显著增加90.91%、135.73%和33.33%;相同种植模式下,与施用标准肥料相比,减半肥料使单作玉米百株籽粒重显著降低22.45%。与单作大豆相比,在施用标准肥料下,间作大豆的百株籽粒重和千粒重分别显著降低49.47%和11.54%,在施用减半肥料下,间作大豆的百株生物量、百株籽粒重和千粒重分别显著降低73.94%、50.51%和17.39%;相同种植模式下,与施用标准肥料相比,减半肥料使大豆在单作和间作下的百株籽粒重分别显著降低65.02%和65.73%,使间作下大豆的百株生物量和千粒重分别显著降低73.14%和17.39%。与单作相比,间作均显著降低了标准肥料和减半肥料处理下玉米和大豆害虫群落的物种数、多样性指数和均匀度指数,还显著降低了标准肥料和减半肥料处理下玉米天敌昆虫群落的物种数和优势度指数以及大豆天敌昆虫群落的物种数和均匀度指数。表明玉米-大豆间作能有效提高玉米产量,降低虫害发生,但对大豆生产不利,而间作条件下减施肥料对玉米产量的影响更小。建议在田间生产中可将夏玉米和大豆间作种植,更有利于通过生态学方法控制田间害虫发生和增加作物总体产量。 相似文献
978.
近几年来,锯缘青蟹人工育苗技术虽然得以逐步推广,但提高锯缘青蟹人工育苗的成活率和出苗率,仍是目前苗种生产中探索的主要问题.就此笔者认为在锯缘青蟹人工育苗中应注意掌握以下几个方面的技术关键. 相似文献
979.
Qin Wen-chao Chen Zhi-hui Chen Ying-lin Ma Cheng-zhan Sun Hao Lian Li-na Zhao Ze-yu Zhao Cheng Sun Jia-you Bai Yang Xu Liang-mei 《东北农业大学学报(英文版)》2021,28(4):56-67
The purpose of this experiment was to isolate and screen the microorganisms from the soil where chicken feathers were piled for a long time and identify them bi... 相似文献
980.
Hongwei Luo Xinbin Duan Shaoping Liu Daqing Chen 《Fish physiology and biochemistry》2014,40(5):1521-1532
The study assessed the effects of surgically implanted dummy ultrasonic transmitters on physiological response of bighead carp Hypophthalmichthys nobilis in April 2011. Before the surgery, 15 blood samples were extracted randomly from 195 bighead carp samples, and then the rest of the fish were divided into three groups: (1) control group, handing but no tagging, (2) sham group, surgical procedure without implantation of transmitter and (3) surgery group, surgical implantation of transmitters. In 3 h, 24 h, 7 days and 14 days after surgery, 15 fish were extracted randomly from the three groups, respectively, for sampling. Then the plasma samples were analyzed, and physiological measures of stress response (cortisol, glucose), tissue damage [alanine aminotransferase (ALT) and aspartate aminotransferase (AST)] and nutritional status [total protein, globulin, albumin, triglyceride, cholesterol, and alkaline phosphatase (ALP)] were compared. The result showed that there was no significant difference between sham and surgery groups in 3 h, 24 h, 7 days and 14 days after surgery. When compared to the control group, there were significant increases in concentrations of plasma cortisol, glucose, ALT, AST, total protein and globulin of sham and surgery groups in 3 h after surgery. After 24 h, the levels of plasma cortisol, ALT, AST, total protein, globulin and ALP were elevated in both sham and surgery groups, whereas the levels of plasma glucose had declined to normal level and plasma albumin, cholesterol and triglyceride were significantly decreased in both sham and surgery groups. After 7 days, the levels of plasma glucose, albumin and cholesterol continued to decline, while the level of plasma ALT, globulin and ALP had declined but still remained higher for sham and surgery groups than control group; however, the plasma total protein level had returned to normal. After 14 days, there was no significant difference between the three groups. The above results showed that surgical implantation of ultrasonic transmitters had indeed caused significantly negative effects on the physiological response of bighead carp. However, all the negative influences on stress response, tissue damage and nutritional status had disappeared in 14 days after surgery, and the presence of transmitters had no significant negative impact. Therefore, the bighead carp should be temporary cultured at least 14 days for the recovery of physiological response and then released into the free water for the ultrasonic telemetry research. 相似文献