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121.
本文介绍了甘蓝型中熟双低油菜杂交种湘杂二号,在青海省的高产制种栽培技术方法,以及制种地的选择,隔离区的处理,田间管理等一系列科学的技术方法。  相似文献   
122.
本文介绍了应用25%丁苄细粒剂、10%苄黄隆可湿性粉剂加50%丁草胺与尿素混合撒施对晚造免耕抛秧田杂草的防治效果、安全性和增产作用。试验结果表明:在水稻抛栽后5d施丁苄80g、120g以及在抛栽后7d施苄黄隆15g加丁草胺150g对晚造免耕抛秧田的主要杂草如稗草、矮慈姑、鸭舌草、异型莎草和节节菜等均有显著的防效,其总体防治效果可分别达到82.26%、91.13%和93.35%,且对水稻生长无不良影响,保产作用明显。  相似文献   
123.
新型竹编水泥沼气池力学性能的测试与理论研究   总被引:6,自引:1,他引:5  
分析了目前在滇南一带开发推广的新型竹编水泥沼气池结构特点,并从实地测试和实验室测试、理论模型的角度,讨论了此类沼气他的结构性能,特别在理论模型研究中,分别针对二维、三维几何模型进行了计算机数值仿真,得到了一些和实地测试一致的结果。实验研究及理论分析说明此类竹编水泥沼气池在力学结构上是合理的,在承受荷载上具有足够大的安全系数,同时也指出了竹编水泥沼气池在实际建造过程中,应该重视的一些技术环节,对于进一步在农村推广应用具有重要的现实意义。  相似文献   
124.
Field bean planes cultivar Nadwiślański were submitted to soil drought (30 % of field soil water capacity) for 5 days at the stage of pod formation (A) and of rapid pod growth (B) and then exposed for 20 minutes to 14CO2. Radioactivity of leaves, stems, roots, and pods or pod shells and seeds was measured 1, 5, 24 and 48 hours after exposition.
In both stages soil drought reduced by about five times total CO2 assimilation, mainly owing to lower activity of the photosynthetic apparatus and also, though less so, to reduced leaf growth. Photosynthetic activity referred to the dry weight of the leaves dropped to 22-35% of controls. Accumulation of photosynthetates in generative organs was much less depressed than 14CO2 assimilation. 48 hours after exposition to 14CO2 of drought treated plants, the contents of 14C of pods in phase A, and seeds in phase B, amounted to respectively 24% and 36% of assimilated 14C and equalled 91.5% and 74% of the corresponding values for controls.
The progressive decline of radioactivity in leaves and stems after 14CO2 exposition was distinctly correlated to the rise of radioactivity of generative organs both in soil drought treated plants and in controls. Slightly lower values of correlation coefficients in drought treated plants may indicate impairment under drought conditions of synchronization in processes of unloading and accumulation of assimilates.
In plants drought treated in phase A the ability to dissimilate 14C was reduced to about 59% of that in controls, but when drought was applied in phase B, dissimilation rate was about three times as high.  相似文献   
125.
AIM: To explore the changes in serum TGF β1 in type 2 diabetes mellitus. METHODS: Forty-five cases type 2 diabetes mellitus patients were divided into three groups according to urine albumim excretion rate(UAER): normoalbuminuria(NA)group and microalbuminuria(MA) group and macroalbuminuria group (Overt DN). Serum TGF β1, fasting blood glucose(FBG), HbA1c,BUN,Cr,Ccr,lipidemia were detected in all cases. RESULTS: Serum TGF β1 in NA, MA and ODN groups was higher than that in control. Serum TGF β1 was positive correlation with Cr(r=0.390,P<0.05), LDL(r=0.503,P<0.01), HbA1c (r=0.676,P<0.01), and UARE(r=0.777,P<0.01). CONCLUSION: Type 2 diabetes mellitus have a higher serum TGF β1 than controls, serum TGF β1 was positive correlation with HbA1c and injury of renal function.  相似文献   
126.
<正>一 引言 森林采伐,首先要进行生产工艺和工程设计,由于这项工作大部分在野外进行,作业范围大,特别是南方山地林区地形复杂,导致外业工作量大,效率低。因此,我们尝试利用航测技术来解决。利用它把大量的外业工作移至室内进行,节省人力、物力,并能提高工作效率和工艺设计精度。同时航片上所反映的信息很多,借助一定的仪器设备进行立体观察,分析,测量和比较,这样在进行生产工艺和工程设计时,便于综合考虑多种影响因素,从而保证所选择的工艺方案经济上合理,技术上先进可行。由此可见利用航测技术进行森林采伐工艺设计,对改善作业条件,提高劳动效率,作业精度,以及提高林业现代化水平都具有重要意义。为此,我们就应用航测技术进行工艺设计做了些试验,探讨其可行性及适用程度。然而本文仅是最初的探讨,有些问题还有待于讲一步解决与完善。  相似文献   
127.
The aim of this study was to evaluate single and double centrifugation tube methods for concentrating equine platelets. Whole blood samples were collected from clinically normal horses and processed by use of single and double centrifugation tube methods to obtain four platelet concentrates (PCs): PC-A, PC-B, PC-C, and PC-D, which were analyzed using a flow cytometry hematology system for hemogram and additional platelet parameters (mean platelet volume, platelet distribution width, mean platelet component concentration, mean platelet component distribution width). Concentrations of transforming growth factor beta 1 (TGF-beta(1)) were determined in all the samples. Platelet concentrations for PC-A, PC-B, PC-C, and PC-D were 45%, 44%, 71%, and 21% higher, respectively, compared to the same values for citrated whole blood samples. TGF-beta(1) concentrations for PC-A, PC-B, PC-C, and PC-D were 38%, 44%, 44%, and 37% higher, respectively, compared to citrated whole blood sample values. In conclusion, the single and double centrifugation tube methods are reliable methods for concentrating equine platelets and for obtaining potentially therapeutic TGF-beta(1) levels.  相似文献   
128.
大拱棚四膜覆盖栽培马铃薯高产技术   总被引:1,自引:0,他引:1  
在马铃薯二季作地区,采用四膜栽培新技术进行早春马铃薯高产栽培。结果表明:通过早春四膜栽培技术的实施,马铃薯生育期比露地栽培提早近2个月,平均产量达到42000kghm-2,每公顷收入15万元以上,经济效益明显提高,值得在生产上推广。  相似文献   
129.
从广西蚕区的野外昆虫菜粉蝶(Pieris rapae)、桑尺蠖(Hemerophila atrilineata)、斜纹夜蛾(Spodoptera litura)的体内收集到5株对家蚕有一定食下感染力的微孢子虫,通过生物学性状、分子系统发育研究,为其分类鉴定提供依据。来自野外昆虫的5株微孢子虫均具有Nosema属的生物学特性:显微镜下观察形状均呈长卵圆形,与家蚕微孢子虫(Nosema bombycis,Nb)有较明显差异;在生活史的各发育阶段均为双核,以二分裂方式增殖,最后形成双核成熟孢子;与Nb抗血清均产生阳性凝聚反应;超微结构观察均具双核,极丝圈数在12~14圈之间,极丝倾斜角与Nb有差异。根据5株野外昆虫微孢子虫与其它昆虫微孢子虫基于SSU rRNA基因序列构建的系统发育树,以及基于SSU rRNA和rRNA ITS基因序列进行的相似性和遗传距离分析,初步认为5株野外昆虫微孢子虫与家蚕微孢子虫同属异种。  相似文献   
130.
AIM:To study the effects of Zuogui pill(ZG)-medicated serum on the proliferation and differentiation of MC3T3-E1 cells via ERK/TGF-β/Smads signaling pathway. METHODS:Using Premarin(conjugated estrogens tablets) as a positive control, the SD female rats were fed with high-, medium- or low-dose of ZG suspension. ZG-medicated serum was separated from abdominal aortic blood 7 d after feeding of ZG. MTT assay was applied to test the effect of ZG-medicated serum on the viability of MC3T3-E1 cells. The production of alkaline phosphatase(ALP) was detected by a modified calcium and cobalt dyeing method. The calcified nodules were observed by the method of alizarin red staining. The levels of core binding factor α1(Cbfα1) and collagen type I(Col I) protein were analyzed by Western blotting. The mRNA expression of TGF-β1, Smad4 and Smad2 was measured by real-time RT-PCR. RESULTS:ZG-medicated serum promoted the proliferation of MC3T3-E1 cells in a dose-and time-dependent manner. Compared with other groups, treatment with 15% ZG(low dose) for 48 h increased the proliferation of MC3T3-E1 cells significantly. The protein levels of ALP, Cbfα1 and Col I,the calcified nodules, and the mRNA expression of TGF-β1, Smad4 and Smad2 in MC3T3-E1 cells were all significantly increased after treatment with ZG-medicated serum. After the addition of PD98059(a specific blocker of ERK1/2 signaling pathway), all those were down-regulated except for mRNA expression of TGF-β1. CONCLUSION:ZG regulates MC3T3-E1 cell proliferation and differentiation via the intervention of ERK/TGF-β/Smads signaling cascade, which may be one of the mechanisms that ZG effectively prevents and treats osteoporosis.  相似文献   
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