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41.
不同粘度矿物油助剂对除草剂活性的影响 总被引:5,自引:1,他引:5
室内及温室内测定了10种不同粘度矿物油助剂对除草剂防除苘麻和稗草药效的影响及对玉米苗期的安全性。结果表明,10种矿物油助剂均不同程度地增加了氰草津和烟嘧磺隆防除两种杂草的活性。其中粘度为46 mm2/s (40℃)的矿物油乳剂(MOC46)对供试除草剂药效的增强作用最为明显,其次为粘度32 mm2/s (40℃)的矿物油乳剂。10种助剂对氰草津药效的增强作用大于对烟嘧磺隆。MOC46对除草剂活性的增加由高到低依次为:莠去津、氰草津>莠去津+氰草津、莠去津+烟嘧磺隆、氰草津+烟嘧磺隆>烟嘧磺隆;对玉米苗期安全性依次为:莠去津、烟嘧磺隆、莠去津+烟嘧磺隆>莠去津+氰草津、氰草津+烟嘧磺隆>氰草津。氰草津与MOC46混用对玉米苗期药害较重。 相似文献
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AIM:To establish rat chronic obstructive pulmonary disease(COPD) models by passive cigarette smoking plus intratracheal instillation of lipopolysacchride(LPS) or passive cigarette smoking only, which would be similar to the pathogenesis of human COPD. METHODS:48 Wistar rats were randomly divided into 4 groups.(1) Healthy control I group(n=12), rats were bred 4 weeks;healthy control II group(n=12), rats were bred for 3months. (2) Model group I (n=12), 200μg lipopolysaccharide(LPS) was instilled intratracheally once for every two weeks and the rats were exposured to 5% of cigarette smoke, 0.5 h/d for 4 weeks.(3) Model group II(n=12),rats were exposed to 5% of cigarette smoke, 0.5 h/d for 3 months. The pathologic changes of airways and lung tissues, pulmonary function and blood gas analysis were determined. The airway wall lymphocytes and alveolar macrophages were counted. The cross areas of epithelial layer, smooth muscle layer and lamina propria of bronchi were measured. The hydroxyproline of lung tissue homogenates was determined by biochemistry method.RESULTS:The pathologic changes of airways and lung tissue of two models were similar to but milder than those of COPD patients(biopsy data). The collagen deposition and the cross areas of epithelial layer and smooth muscle layer in airway walls of two model groups were significantly increased than those of control groups(P<0.01,P<0.05).FEV0.3/FVC% of two model groups, PaO2 and SaO2 of model I group were significantly decreased, while Ri and Re in model I group were significantly increased than that of control I group(P<0.05). The PaCO2 and the counts of lymphocytes and alveolar macrophages of both model groups were significantly increased than those of the control groups (P<0.01). Lots of alveolar macrophages had phagocyted smoke granules. The amounts of hydroxyproline of two model groups were significantly increased than those of control group((P<0.05) and were negatively related to the FEV0.3/FVC%, respectively (P<0.01,P<0.01) and positively related to airway resistance of model I group(P<0.01). CONCLUSIONS:COPD rat models were successfully established by passive cigarette smoking plus intratracheal instillation of LPS and cigarette smoking only. The pathologic changes were similar but milder than those of COPD patients. The airway obstruction of model I group was more severe than that of model II group, but they have no significant difference. 相似文献
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AIM: To investigate the relationship between somatostatin and the pathologic type, estrogen receptor,DNA ploidy of nuclei in tumor cells of breast cancer.METHODS: 67 cases of primary breast cancer and 25 cases of benign breast tumor were examined by immunohistochemical stretomyces avidin peroxidase method. 26 cases of breast cancer selected at random were analyzed by flow cytometry.RESULTS: Somatostatin expressed significantly higher in low malignant breast cancer than that in high malignant breast cancer (P<0.05). Most of cancers with positive staining of somatostatin were diploidy,most of cancers with negative staining were aneuploidy,there had significant difference between two groups (P<0.05).CONCLUSION: Somatostatin may delay the progress of breast cancer,and somatostatin levels in cancer tissues may become a useful indicator for assessing prognosis of patients with breast cancer. 相似文献
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实验室条件下系统研究了磷化氢(PH3)对储物害虫嗜卷书虱Liposcelis bostrychophila卵、各龄若虫和成虫的致死作用,并选用PH3间歇熏蒸以及PH3与气调交替处理等措施对嗜卷书虱进行处理,比较了不同处理措施对嗜卷书虱种群的控制效果。结果表明,PH3熏蒸处理对嗜卷书虱各虫态有不同的致死效果。对卵而言,24、72和120 h熏蒸处理的LC50分别为0.137、0.045和0.035 mg/L;而24 h熏蒸处理对若虫的LC50在4.285~7.364 μg/L之间,对成虫的LC50为20.404 μg/L;采用25 μg/L的PH3进行24 h熏蒸处理,间隔10 d后再分别进行第2次和第3次熏蒸处理,可以完全控制嗜卷书虱的发生。采用PH3 (12 μg/L)和气调(体积比例为35% CO2,1% O2,64% N2)交替处理能够延缓嗜卷书虱种群抗性的发展,交替处理3~5次可以完全控制嗜卷书虱的发生。 相似文献
47.
甘薯由于甘薯病毒的普遍存在而造成大幅度减产。甘薯病毒种类复杂,主要有甘薯羽状斑驳病毒(SPFMV)、甘薯潜隐病毒(SPLV)、黄瓜花叶病毒(CMV)、烟草花叶病毒(TMV)。 相似文献
48.
淡紫拟青霉菌料防治大豆胞囊线虫的后效研究 总被引:6,自引:2,他引:6
淡紫拟青霉不同菌株的培养菌料,施225kg/hm2,对大豆胞囊线虫不但当年有45%~69%的较好防效,而且第2年和第3年仍然有22.5%~37.7%和7.3%~22.9%的后效,即空胞囊和被寄生的胞囊数量增加。 相似文献
49.
春麦田除草剂的应用与杂草群落演替 总被引:10,自引:1,他引:10
作者采用定点定位试验,对春麦田除草剂应用与杂草群落演替趋势进行研究。结果表明:在杂草群落多样性麦田,小麦连作并分别连续5年施用同一种除草剂,原杂草群落中占优势的靶标杂草得以控制,而非靶标杂草和抗、耐药性杂草因失去竞争和制约对象而猖獗发展,发生量较原来增加几倍至几十倍,并形成优势种群,对小麦造成新的更严重的危害。一种除草剂在同田块连续施用4年,由于杂草群落演替,抗、耐药杂草兴起,除草效果显著下降而失去其使用意义。作者提出除草剂配套使用、轮用、混用等措施,并配合以合理的轮作制度,以减轻杂草群落长期受到单一的定向选择性压力。 相似文献
50.