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排序方式: 共有619条查询结果,搜索用时 218 毫秒
21.
红花大金元、G28和K326烤烟种子搭乘"神舟一号"宇宙飞船空间飞行回收后贮存,连续7年观察发芽势、发芽率、发芽指数.结果表明,种子活力指标有显著的太空飞行、品种和贮存时间效应.发芽势、发芽率、发芽指数在贮存1年后随贮存时间推移而呈现下降的趋势,太空飞行种子的低于地面对照组.发芽势、发芽指数的太空飞行绝对效应和相对效应.G28显著高于HD和K326.贮存时间与种子发芽势、发芽率和发芽指数太空飞行相对效应和绝对效应呈极显著正相关关系.起始种子活力指标对太空飞行效应有明显的影响.  相似文献   
22.
AIM To explore the effects of oxidative stress and inflammatory response on kidney injury induced by hyperthyroidism in mice. METHODS Forty male Kunming mice were randomly divided into control group (n=20) and L-thyroxine (T4) group (n=20). The mice in T4 group were intraperitoneally injected with T4 diluent at a dose of 1 mg/kg to induce hyperthyroidism, and those in control group were injected with normal saline of the same volume. After 7 weeks, the mice were weighed and dissected, the kidneys were removed and weighed, and the length of tibia was also measured. The activity of superoxide dismutase (SOD) and the content of malondialdehyde (MDA) in the kidney tissues were detected. The pathological changes of the kidney tissues were observed by HE staining. The levels of 4-hydroxynonenal (4-HNE)-modified proteins, interleukin-1 receptor-associated kinase 1 (IRAK1) and tumor necrosis factor receptor-related factor 6 (TRAF6) were determined by Western blot and immunohistochemistry. RESULTS Compared with control group, the body weight of the mice was decreased, while the kidney size and weight were increased significantly in T4 group. In addition, the ratios of kidney weight/body weight and kidney weight/tibia length were also increased (P<0.05). In T4 group, the renal tubules were enlarged, and the epithelial cells of renal tubules were swollen and exfoliated, with vacuolar degeneration. Furthermore, reduced SOD activity, and increased MDA content and 4-HNE-modified proteins were found in T4 group, all of which were related to oxidative stress (P<0.05). The levels of inflammation-related proteins IRAK1 and TRAF6 were significantly increased in T4 group (P<0.05). CONCLUSION Excessive T4 may lead to kidney hypertrophy and injury in mice, and the mechanism may be related to oxidative stress and inflammatory response.  相似文献   
23.
AIM To investigate the effects of cytochrome P450 (CYP450) epoxygenase/epoxyeicosatrienoic acid (EET) pathway on insulin resistance in obese mice, and to explore the possible mechanisms. METHODS High-fat diet-induced obesity model was established in C57BL/6Cnc mice, and the obese mice were randomly divided into 3 groups, including obesity group (treated with saline; n=10), EET group (treated with 11,12-EET; n=10) and EET inhibitor 14,15-epoxyeicosa-5(Z)-enoic acid (EEZE) group (n=10). Normal C57BL/6Cnc mice (n=10) treated with saline served as control. Protein expression of CYP2J2 (one of CYP450 epoxygenases) and hypoxia-inducible factor-1α (HIF-1α) was measured by Western blot. Vessel-like structure was detected by immunofluorescence staining. The serum levels of insulin, tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6 and monocyte chemoattractant protein-1 (MCP-1) were measured by ELISA. RESULTS In obese mice, homeostasis model assessment of insulin resistance (HOMA-IR) values were increased, the protein level of CYP2J2 was reduced, and the protein level of HIF-1α was increased in adipose tissues as compared with the controls (P<0.05). The serum levels of MCP-1, IL-1β, IL-6 and TNF-α were also significantly increased in obese mice (P<0.05). After treatment with 11, 12-EET, the HOMA-IR values were decreased compared with vehicle-treated obese mice, HIF-1α expression levels were decreased in the adipose tissue, and the serum levels of MCP-1, IL-1β, IL-6 and TNF-α were reduced (P<0.05). Immunohistochemical results of adipose tissue from vehicle-treated obese mice showed a marked decrease in vessel-like structures (CD31-positive) compared with normal control mice (P<0.05). EET treatment significantly increased the newly formed vessel-like structures in the visceral adipose tissues of obese mice as compared with vehicle-treated obese mice (P<0.05). CONCLUSION High-fat diet-induced obesity and insulin resistance are closely related to the CYP450 pathway. Exogenous EETs effectively decrease obesity-induced insulin resistance possibly through pro-angiogenesis and attenuation of hypoxia and inflammation.  相似文献   
24.
用不同剂量的^60 Co-γ射线对苋菜种子进行辐射,观测其对苋菜种子发芽率和幼苗生长的影响。结果表明,在该实验设计的辐射剂量范围(20-200Gy)内,对苋菜种子有刺激生长的作用,20Gy有利于苋菜种子发芽,60~80Gy有利于苋菜幼苗的生长。  相似文献   
25.
利用184个样地的627组数据对16种生长模型的参数进行了拟合,结合Ⅰ-69杨的生物学特性和拟合效果,确定利用单分子曲线作为Ⅰ-69杨的立地指数的导向曲线并编制了立地指数表.根据实际情况将立地指数划分为3个地位级.  相似文献   
26.
目的总结鼻内镜下脑脊液鼻漏的治疗经验,探讨鼻内镜下定位和修复的方法。方法回顾分析6例脑脊液鼻漏病人诊治过程,对脑脊液鼻漏的定位及修复方法进行讨论。结果6例病人,男、女各3例,年龄28~45岁。医源性2例,外伤性2例,自发性脑脊液鼻漏2例。于鼻内镜下寻找漏出部位,发现位于颅前窝3例,位于蝶窦3例。以明胶海绵蘸生物蛋白胶加鼻黏膜修复4例,生物蛋白胶加肌肉、阔筋膜加脂肪、阔筋膜各1例。83%(5/6)1次修复成功、1例2次修复成功。结论鼻内镜下脑脊液鼻漏定位和修复具有方法简捷、疗效确切,推荐作为脑脊液鼻漏治疗的首选方法。  相似文献   
27.
强继业 《核农学报》2004,18(1):47-50
应用3 2 P研究了不同臭氧浓度对水培烤烟吸收磷素营养的影响。结果表明 :在水培法中低浓度臭氧使根对磷素吸收量所占全植株的百分率随培植时间而减少 ,而茎则随培植时间而增加 ;高浓度臭氧则在整个培植期间根、茎的吸收变化不大。两种培植方法磷素在叶中的分布情况都是 :下叶 >中叶 >上叶。烟株各部分的吸收情况 ,根 >茎 >下叶 >中叶 >上叶 ,且两种培植方法对磷的吸收量都与培植时间呈显著正相关 ,高浓度比低浓度臭氧吸收的磷多而快  相似文献   
28.
邵菁  戴伟民  张连举  宋小玲  强胜 《作物学报》2011,37(8):1324-1332
前期调查研究表明江苏是中国杂草稻危害最严重的省份之一,尤其以苏中地区最甚。因此,本文利用具有多态性的33个共显性SSR标记,分析苏中地区的11个杂草稻种群以及苏南苏北部分杂草稻样品,以揭示江苏省主要杂草稻的遗传多样性及其来源。结果表明苏中地区11个杂草稻群体总的遗传多样性(He)为0.1661,Shannon指数(I)为0.2872;多态位点百分率达到87.88%,等位基因数(Na)为2.1515,有效等位基因数(Ne)为1.2887。其中,泰州的遗传多样性最高而南通地区的最低。杂草稻在地区之间的遗传分化(1%)显著小于杂草稻种群之间的遗传分化(39%),更小于种群内的遗传分化(60%)。聚类分析和主成分分析结果表明苏中和苏南地区杂草稻以籼型为主,苏北地区存在少量粳型杂草稻;苏中地区的杂草稻与现有栽培稻品种和普通野生稻没有明显的亲缘关系,但与曾经栽培过的杂交水稻品种有关。因此,本研究相对支持江苏省杂草稻可能主要来自栽培稻的基因重组或回复突变等产生野生性状即返祖遗传的假说。苏北地区的杂草稻可能来源于穞稻与现今栽培稻杂交的后代。  相似文献   
29.
田间药效试验结果表明:10%丁醚脲微乳剂对小菜蛾有较好的防治效果,156g/hm2对小菜蛾的防效可达98.47%。  相似文献   
30.
庆城县黄花菜生产现状及发展建议   总被引:2,自引:0,他引:2  
在分析庆城县黄花菜生产现状和存在问题的基础上,从加大宣传力度,提高庆阳黄花菜的知名度;依托企业打造品牌,开展黄花菜绿色认证;加强产中、产后服务,提高黄花菜的经济效益等方面提出了庆城县发展黄花菜生产的建议。  相似文献   
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