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21.
近红外光谱技术在水果内部品质无损检测中的应用   总被引:6,自引:0,他引:6  
针对近红外光谱分析技术在水果内部品质无损检测的应用问题,简单介绍了近红外光谱的基本原理;描述了国内外近红外光谱分析技术无损检测水果内部品质的最新研究进展;并指出当今国内外研究中存在的问题和今后进一步的研究设想。  相似文献   
22.
国际市场中要求竹苗的出口不能带土,根据基质选择的原则及评价的标准,配制了8种基质(G1、G2、G3、G4、G5、G6、G7、G8)作为鸡毛竹(S.chinensis Nakai)和黄条金刚竹(Pleioblastus kongosanensis f.aureostriaus)的容器育苗基质.结果表明:在G8中,鸡毛竹、黄条金刚竹的生长情况最好,在G3、G7中,鸡毛竹、黄条金刚竹的生长情况较好,但成本相对较高.在泥炭中加入山核桃壳或煤渣等经济基质材料,降低了成本,改善了基质的通气性和保水性.  相似文献   
23.
在掌握了褐环粘盖牛肝菌生态学特性、野生增产技术、菌种分离扩繁、菌剂制作、菌根苗培育技术的基础上,开展了在旱地采用栽种褐环粘盖牛肝菌菌根苗的人工栽培试验,试验采用不同基质培育菌根苗,并对栽培出菇效果进行了比较.通过菌根苗移栽与无菌苗就地接种培育菌根苗的栽培试验,研究了催菇处理对出菇的影响,研究表明,采用栽种菌根苗取得了褐环粘盖牛肝菌人工栽培的成功,单产高达283.57 g·m-2,采用带土基质培育的菌根苗出菇效果明显优于无土基质,移栽菌根苗的出菇效果优于就地接种培育菌根苗,催菇处理的效果十分显著.  相似文献   
24.
AIM: To investigate the possible role of endothelin(ET-1) in asthma pathogenesis and the effect of atrial natriuretic factor (ANF) on changes of ET-1. METHODS: Measuring the contents of endothelin-1(ET-1),atrial natriuretic factor(ANF),cGMP in plasma and bronchoalveolar lavage fluid (BALF) of guinea pigs. RESULTS: The contents of ET-1, ANF and cGMP in asthma group were higher than that of the control group; There was a significant negative correlation between ET-1 and ANF( r=-0.638,P <0.05) in plasma of the asthma group, and a significantly negative correlation between ET-1 and ANF( r=-0.921,P <0.01) in BALF of the asthma group. There was a significantly positive correlation between ANF and cGMP( r=0.848,P <0.01) in plasma of the asthma group,and a significantly positive correlation between ANF and cGMP ( r=0.831,P <0.01) in BALF of the asthma group. The levels ET-1 in the asthma+rat ANF(rANF) group were lower than those in the asthma group,and the levels of cGMP in the asthma+rat ANF(rANF) group were higher than those in the asthma group after ceasing to infuse rANF for guinea pigs for 30 minutes.CONCLUSION: ET-1 might play an important role in the pathogenesis of asthma.ANF might inhibit production of ET-1.  相似文献   
25.
AIM: To investigate the protective effect of curcumin analogue L6H4 on diaphragm of type 2 diabetic rats.METHODS: SPF male Sprague-Dawley rats (n=40) were randomly divided into 5 groups: normal control (NC) group, high fat (HF) group, high fat+L6H4 treatment (FT) group, diabetes mellitus (DM) group and DM+L6H4 treatment (DT) group. The rats in the later 4 groups were fed with high-fat diet. After 4 weeks of high-fat diet fee-ding, the rats in DM and DT groups were intraperitoneally injected with streptozotocin to induce type 2 diabetes melliutus. The rats in FT and DT groups were given L6H4 by gavage for 8 weeks. Blood glucose and blood lipid levels were detected biochemically. Fasting serum insulin (FINS) level was measured by radioimmunoassay and insulin resistance index (HOMA-IR) was calculated. Serum adiponectin (APN) level was measured by ELISA. The morphological changes of the diaphragm were observed under light and transmission electron microscopes. Lipid deposition and the activity of succinate dehydrogenase (SDH) and NADH-tetrazolium reductase (NADH-TR) were observed by enzyme histochemical staining. The content of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) in the diaphragm were measured by thiobarbituric acid method and hydroxylamine method, respectively. The protein expression of adiponectin receptor 1 (AdipoR1) in the diaphragm was determined by immunohistochemistry and Western blot. RESULTS: The levels of blood lipids, blood glucose, FINS and HOMA-IR in HF and DM groups were higher than those in NC group, but decreased after L6H4 treatment. The serum APN level in HF and DM groups was lower than that in NC group, but increased after treatment with L6H4. The muscle fibers of the diaphragm were shrunk, fat particles accumulated in the muscle fibers, and the mitochondria were slightly swollen in HF and DM groups. The diaphragmatic fibrosis was obvious in DM group. These lesions were relieved after L6H4 treatment. Compared with NC group, the level of MDA and the activity of SDH and NADH-TR in the diaphragm were increased in HF and DM groups, but decreased after treatment with L6H4. The activity of SOD and the expression of AdipoR1 in the diaphragm were lower than those in NC group, but increased after L6H4 treatment.CONCLUSION: The curcumin analogue L6H4 exerts a protective effect on diaphragm in type 2 diabetic rats. The strengthened protein expression of AdipoR1, the increased serum level of APN, and anti-lipid peroxidation may be involved in the process.  相似文献   
26.
不同氮肥用量对番茄生长及植株养分含量的影响   总被引:1,自引:0,他引:1  
利用盆栽试验,研究了不同氮素用量对番茄生长性状、果实品质及植株不同器官氮、磷、钾含量的影响。试验结果表明,N_2(N=2 g/盆)处理的单株结果数(21.5个/株)、平均单果质量(6.5 g/个)均达最高值,该处理所产果实鲜样VC含量(37.5 mg/100 g)和糖酸比(9.4)均为最高,显著高于其他处理(P0.05);植株中氮、磷含量均表现为果实叶茎,而钾含量则表现为果实茎叶。随着氮肥用量的增加,各器官中氮、钾含量均表现为先增加后下降,N_2处理显著高于N_1、CK和N_4(P0.05),该处理果实的VC含量和糖酸比也达最大值;综上,番茄盆栽中纯氮用量以2 g/盆为宜。  相似文献   
27.
AIM:To study the role of microRNA-219 (miR-219) in regulation of transforming growth factor-β receptor type 2 (TGFBR2) in renal fibrosis. METHODS:The renal fibrosis patients (n=70) were selected in this stu-dy, and 20 cases of healthy people were selected as control group. RT-qPCR was used to detect the expression of miR-219 in the serum of the patients with renal fibrosis and control group, and the expression of miR-219 in NRK49F cells after stimulation with angiotensin Ⅱ(AngⅡ) was detected. The protein expression of α-smooth muscle actin (α-SMA) in the NRK49F cells transfected with miR-219 mimics after stimulation with AngⅡ was determined by Western blot. The potential target gene TGFBR2 of miR-219 was screened and verified by the method of luciferase reporter gene. RT-qPCR and Western blot were used to detected the effect of miR-219 mimics on the expression of TGFBR2 at mRNA and protein levels, and the mRNA expression of α-SMA, connective tissue growth factor (CTGF), type I collagen α1 (COL1A1) and COL3A1 in the NRK49F cells was also detected, respectively. The unilateral ureteral occlusion (UUO) mouse model was established and the expression of miR-219 in the renal tissue was monitored. The morphological change of renal fibrosis was observed in the UUO mice after injection of miR-219, and the mRNA expression levels of COL1A1 and COL3A1 were detected. RESULTS:The expression level of miR-219 in the patients with renal fibrosis was significantly lower than that in control group, and the expression of miR-219 in the UUO mice was decreased significantly (P<0.01). The expression level of miR-219 was significantly decreased in the NRK49F cells after AngⅡ stimulation, and miR-219 mimics inhibited the protein expression of α-SMA(P<0.01). miR-219 mimics had a targeted regulatory effect on TGFBR2 gene, which inhibited the mRNA and protein expression of TGFBR2. miR-219 mimics inhibited the mRNA expression of α-SMA, CTGF, COL1A1 and COL3A1. miR-219 also down-regulated the mRNA expression of COL1A1 and COL3A1 in the UUO mice and inhibited the process of renal fibrosis. CONCLUSION:miR-219 inhibits the development of renal fibrosis by inhibiting the expression of TGFBR2, which may become a new target for the diagnosis and treatment of renal fibrosis.  相似文献   
28.
闽引圆叶决明辐射变异后代新品系(86134-32-3)的若干特性   总被引:5,自引:1,他引:4  
从60Coγ射线辐射闽引圆叶决明86134牧草种子种植后代中筛选出性状稳定的优良变异后代新品系86134-32-3。M4代田间小区品比试验表明,与原品种86134相比,新品系植株叶子生长数、干物质含量、粗脂肪含量、氨基酸总量和单位产量都有大幅度的提高,达到显著或极显著水平;其植株茎叶比大幅度下降。新品系植株的其余营养成分、包括生殖生长期在内的农艺性状均保持原品种特性。  相似文献   
29.
信息技术的发展与农业生态工程创新   总被引:1,自引:0,他引:1  
信息技术在农业上的应用日渐成为农业研究的热点。为此,论述了信息技术在农业生产中应用发展,并根据我国多年农业生态工程建设的实践,阐明了农业生态工程研究中的技术路线和原则;从生态工程设计和支持手段、综合发展等方面,论述了基于信息技术的农业生态工程创新。  相似文献   
30.
套种羽叶决明的龙眼园节肢动物群落结构与稳定性研究   总被引:2,自引:2,他引:2  
对两种生态系统龙眼园节肢动物群落进行系统调查研究的结果表明,套种园节肢动物群落物种包括13目74科116种,其中植食性害虫类群53种、捕食与寄生性天敌类群35种、蜘蛛类群13种、腐生性昆虫类群1 5种;单一园(CK)为12目61科85种,其中植食性害虫类群54种、捕食与寄生性天敌类群14种、蜘蛛类群6种、腐生性昆虫类群11种.在单一园中植食性害虫类群的相对多度为98.16%,捕食性与寄生性类群、蜘蛛类群、腐生性昆虫类群的相对多度分别为0.52%、0.16%、1.16%;套种园中各类群的相对多度分别为91.89%、3.07%、0.66%、4.38%;套种园捕食性与寄生性昆虫类群、腐生性昆虫类群数量及相对多度均高于单一园,植食性害虫类群数量及相对多度小于单一园.套种园与单一园相比,具有更高的丰富度、多样性、均匀度和稳定性,群落结构更合理,说明龙眼园套种羽叶决明(Chamaecrista nictitans cv.Minyin)能有效增加果园物种丰富度、多样性、提高均匀度和稳定性,对促进天敌繁衍栖息,减少害虫发生,优化群落结构,保护果园生态平衡具有重要意义,是龙眼园生物多样性保护、利用和害虫综合控制的有效途径之一.  相似文献   
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