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Studies on hybridization effects of different geographic populations of Chlamys farreri Ⅱ.The medium-term growth and development of Chlamys farreri populations from China and Russia and their reciprocal crosses 被引量:12
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作者 LiuXiaolin ChangYaqing +3 位作者 XiangJianhai LiFuhua LiuXianjie BrovkinaElenaPavlovna 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2003年第2期255-264,共10页
Based on the research of juvenile (2, 3, 4 months) growth and survival of three populations of two different geographic areas in Chlamys farreri from Russian and China and their F1 hybrids derived from Chinese cultura... Based on the research of juvenile (2, 3, 4 months) growth and survival of three populations of two different geographic areas in Chlamys farreri from Russian and China and their F1 hybrids derived from Chinese cultural population (CC) (?) × Russian population (RW) (?) , Chinese wild population (CW) (?) × Russian population (RW) (?), Russian population (RW) (?) × Chinese wild population (CW) (?) , the study of the medium-term (6, 8, 10, 12 months) growth and development of Chlamys farreri was carried out. The four determined results indicated that there existed different extent heterosis (3% -52%) for the growth in three types of F1 hybrids, and the offspring derived from CC(?) ×R(?) had a stronger heterosis among the crosses at the medium-term; the uptrend among traits are wet weight >shell width>shell length> shell height, Chinese cultural population could be recognized as excellent parent, and seasonal variations influence very much on the daily increment and growth rate of each trait of Chlamys farreri and it is only able to survive and could barely grow in winter (6-8 months), but grows fast in temperate season (10-12 months). 展开更多
关键词 Chlamys farreri POPULATION hybridIZATION medium-term growth and development HETEROSIS
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Studies on the Growth Habits and Characteristics of Two Polyploid Indica-Japonica Hybrid Rice with Powerful Heterosis
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作者 SONG Zhao-jian DU Chao-qun DAI Bing-cheng CHEN Dong-ling CHEN Jian-guo CAI De-tian 《Agricultural Sciences in China》 CAS CSCD 2007年第3期265-274,共10页
Based on a series of polyploid indica-japonica hybrid plant lines obtained from a new breeding strategy of using double predominance of wide cross and polyploidization to breed super flee, two polyploid indica-japonic... Based on a series of polyploid indica-japonica hybrid plant lines obtained from a new breeding strategy of using double predominance of wide cross and polyploidization to breed super flee, two polyploid indica-japonica hybrids, PSR073 and PSR120 were studied in their growth periods to show the powerful heterosis in a larger scale and to study the characteristics of polyploid indica-japonica hybrids more elaborately. The leaf age, tiller growth, flowering habits, and agronomic traits of them were observed to analyze their growth habits and characteristics. The results showed that the.agronomic traits of PSR073 and PSR120, such as the plant height, panicle length, grain length, grain width, and 1000-grain weight, all acquired obvious predominance of polyploidy, and that the seed setting rate was more than 83%. No significant difference was observed between the two tetraploids and common diploids in the leaf age, tiller growth, and flowering habits. It was concluded that the characteristics of the two powerful heterosis polyploid hybrids were different from those of the polyploid rice reported earlier. Wide cross and polyploidization had no negative effects on their growth habits and characteristics; on the contrary these had powerful heterosis. This had provided theoretic and practical evidences for their application to agricultural production. 展开更多
关键词 POLYPLOID indica-japonica hybrids growth habits and characteristics HETEROSIS seed setting rate
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Comparisons of Yield and Growth Behaviors of Hybrid Rice Under Different Nitrogen Management Methods in Tropical and Subtropical Environments 被引量:13
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作者 Ibrahim Md PENG Shao-bing +3 位作者 TANG Qi-yuan HUANG Min JIANG Peng ZOU Ying-bin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第4期621-629,共9页
To compare the grain yield and growth behaviors of hybrid rice, field experiments were conducted in a subtropical environment in Changsha, Hunan Province, China, and in two tropical environments in Gazipur and Habigan... To compare the grain yield and growth behaviors of hybrid rice, field experiments were conducted in a subtropical environment in Changsha, Hunan Province, China, and in two tropical environments in Gazipur and Habiganj in Bangladesh during 2009 to 2011. Three hybrid rice cultivars were grown under three nitrogen (N) management treatments in each experiment. The results showed that grain yield was significantly affected by locations, N treatments and their interaction but not by cultivars. Changsha produced 8-58% higher grain yields than Bangladesh locations. Sink size (spikelet number per unit land area) was responsible for these yield differences. Larger panicle size (spikelet number per panicle) contributed to greater sink size in Changsha. Aboveground total biomass was greater in Changsha than in Bangladesh locations, whereas harvest index was higher in Bangladesh locations than in Changsha. Crop growth rate (CGR) was greater at Changsha than Bangladesh locations during vegetative phase, while the difference was relatively small and not consistent during the later growth phases. Higher leaf area index and leaf area duration were partly responsible for the greater CGR in Changsha. Real-time N management (RTNM) produced lower grain yields than fixed-time N management in more than half of the experiments. Our study suggested that further improvement in rice yield in the tropical environments similar to those of Bangladesh will depend mainly on the ability to increase panicle size as well as CGR during vegetative phase, and the chlorophyll meter threshold value used in RTNM needs to be modified according to environmental conditions and cultivar characteristics to achieve a desirable grain yield. 展开更多
关键词 crop growth rate biomass production hybrid rice leaf area duration leaf area index real-time nitrogenmanagement
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Analysis of grain growth in hybrid weld HAZ based on the coupled thermo-fluid model
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作者 张转转 武传松 《China Welding》 EI CAS 2015年第1期50-55,共6页
Accurate calculation of thermal cycles is a prerequisite to model grain growth in the heat-affected zone (HAZ). To improve the computation precision of thermal field and HAZ geometry, a coupled model of heat transfe... Accurate calculation of thermal cycles is a prerequisite to model grain growth in the heat-affected zone (HAZ). To improve the computation precision of thermal field and HAZ geometry, a coupled model of heat transfer and fluid flow is developed for laser + GMAW-P hybrid welding of TCS stainless steel. Utilizing computed temperature fields from the coupled model, the evolution of grain structure in the HAZ of TCS stainless steel in hybrid welding is numerically simulated by using a three dimensional Monte Carlo model. Simulation results show that more accurate HAZ grain structure can be obtained based on the coupled model of fluid flow and heat transfer, and the computed grain size distribution agrees well with the corresponding experimental results. 展开更多
关键词 grain growth HAZ hybrid welding numerical analysis
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Green Approach for <i>In-Situ</i>Growth of CdS Nanorods in Low Band Gap Polymer Network for Hybrid Solar Cell Applications
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作者 Ramil K. Bhardwaj Vishal Bharti +9 位作者 Abhishek Sharma Dibyajyoti Mohanty Vikash Agrawal Nakul Vats Gauri D. Sharma Neeraj Chaudhary Shilpa Jain Jitender Gaur Kamalika Banerjee Suresh Chand 《Advances in Nanoparticles》 2014年第3期106-113,共8页
In-situ growth of CdS nanorods (NRs) has been demonstrated via solvothermal, in a low band gap polymer, poly [[4,8-bis[(2-ethylhexyl)oxy] benzo [1,2-b:4,5-b’] dithiophene-2,6-diyl] [3-fluoro-2-[(2-ethylhexyl) carbony... In-situ growth of CdS nanorods (NRs) has been demonstrated via solvothermal, in a low band gap polymer, poly [[4,8-bis[(2-ethylhexyl)oxy] benzo [1,2-b:4,5-b’] dithiophene-2,6-diyl] [3-fluoro-2-[(2-ethylhexyl) carbonyl] thieno [3,4-b] thiophenediyl]] (PTB7). It is a high yielding, green approach as it removes use of volatile and hazardous chemicals such as pyridine as ligand which are conventionally used to synthesize precursors of CdS (NRs). Moreover the solvothermal process is a zero emission process being a close vessel synthesis and hence no material leaching into the atmosphere during the synthesis. The PTB7:CdS nanocomposite has been characterized by SEM, XRD, FTIR, UV-visible spectroscopy techniques. The photoluminescence (PL) spectroscopy study of PTB7 with CdS NRs has shown significant PL quenching by the incorporation of CdS NRs in PTB7;this shows that CdS NRs are efficient electron acceptors with the PTB7. The PTB7:CdS is used as active layer in the fabrication of hybrid solar cells (HSC) as donor-acceptor combination in the bulk heterojunction (BHJ) geometry. The HSCs fabricated using this active layer without any additional supporting fullerene based electron acceptor has given power conversion efficiency of above 1%. 展开更多
关键词 CdS Nanorods PTB7 IN-SITU growth SOLVOTHERMAL hybrid Solar Cell
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Improvement of uniformity in cultivation environment and crop growth rate by hybrid control of air flow devices
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作者 BAEK Min-Seon KWON Sook-Youn LIM Jae-Hyun 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第12期4702-4708,共7页
A complete control type plant factory has high efficiency in terms of cultivation area by constructing vertical multiple layered cultivation beds.However,it has a problem of irregular crop growth due to temperature de... A complete control type plant factory has high efficiency in terms of cultivation area by constructing vertical multiple layered cultivation beds.However,it has a problem of irregular crop growth due to temperature deviation at upper and lower beds and increases in energy consumption by a prolonged cultivation period.In this work,air flow rate inside a facility was improved by a hybrid control of air flow devices like air conditioning and air circulation fan with an established wireless sensor network to minimize temperature deviations between upper and lower beds and to promote crop growth.The performance of proposed system was verified with an experimental environment or Case A wherein air conditioning device was operated without a control algorithm and Case B wherein air conditioning and circulation fans were alternatively operated based on the hybrid control algorithm.After planting leafy vegetables under each experimental condition,crops were cultivated for 21 days.As a result,Case B wherein AC(air conditioning) and ACF(air-circulation fan) were alternatively operated based on the hybrid control algorithm showed that fresh mass,number of leaves,and leaf length for the crops grown were increased by 40.6%,41.1%,and 11.1%,respectively,compared to Case A. 展开更多
关键词 air flow devices hybrid control cultivation environment UNIFORMITY growth rate
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饲料磷水平对虎龙杂交斑生长、骨矿化及肝脏、血液相关生理生化指标的影响
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作者 周智愚 邓银生 +2 位作者 张金枫 梁程锦 吴小易 《中山大学学报(自然科学版)(中英文)》 CAS 北大核心 2025年第1期147-157,共11页
本文旨在探究饲料不同磷(P)水平对虎龙杂交斑生长、骨矿化及肝脏、血液相关生理生化指标的影响。实验设计了7组以干物质计,其等能(以每100 g计)、等蛋白、等脂分别为1421.2 kJ、47%、8%的实验饲料,饲料中磷的实测值分别为1.05%、1.10%、... 本文旨在探究饲料不同磷(P)水平对虎龙杂交斑生长、骨矿化及肝脏、血液相关生理生化指标的影响。实验设计了7组以干物质计,其等能(以每100 g计)、等蛋白、等脂分别为1421.2 kJ、47%、8%的实验饲料,饲料中磷的实测值分别为1.05%、1.10%、1.20%、1.37%、1.52%、1.59%和1.70%,相应缩写为P1.05、P1.10、P1.20、P1.37、P1.52、P1.59及P1.70,每组3个平行。实验鱼[初始体质量(12.14±0.05)g]每日表观饱食投喂两次(8:00和16:30),养殖周期为6周。分析结果显示,P1.05组体质量增长率(WG)、特定生长率(SGR)和肥满度(CF)均极显著高于其他实验组(P<0.01),蛋白质增长值(PPV)在P1.05和P1.10组高于其他实验组,但各组间无显著差异(P>0.05)。随着饲料磷水平升高,P1.05组血浆及肝脏碱性磷酸酶(ALP)、甘油三酯(TG)含量高于其他实验组,而全鱼灰分以及血浆、肝脏总胆固醇(TC)含量呈现相反趋势。P1.05组血浆钙(Ca)含量在各实验组中最高,而磷含量最低,脊椎骨Ca、P含量在P1.05组均低于其他实验组。P1.05组肝脏胰岛素样生长因子1(igf-1)基因表达水平显著高于其他实验组(P<0.05)。综上所述,在本实验条件下,w=1.05%饲料磷水平已满足虎龙杂交斑幼鱼生长的需要,过高磷水平则会导致实验鱼生长下降。 展开更多
关键词 虎龙杂交斑 饲料磷水平 生长 骨矿化
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Morphological plasticity and phosphorus uptake mechanisms of hybrid Eucalyptus roots under spatially heterogeneous phosphorus stress 被引量:4
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作者 Chuifan Zhou Wuya Jiang +3 位作者 Ying Li Xiaolong Hou Aiqin Liu Liping Cai 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第4期713-724,共12页
In this study, we subjected the root systems of eight Eucalyptus hybrids currently cultivated in southern China to heterogeneous phosphorus stress to provide a scientific basis for the selection of a highly phosphorus... In this study, we subjected the root systems of eight Eucalyptus hybrids currently cultivated in southern China to heterogeneous phosphorus stress to provide a scientific basis for the selection of a highly phosphorus-efficient Eucalyptus variety. When the ability of these hybrids to locate phosphorus under different experimental conditions (phosphorus supply in a homogeneous or heterogeneous manner vs. no phosphorus supply) was compared, the main growth characteristics of Eucalyptus, such as plant height, diameter, dry mass, and phosphorus content, significantly improved when the phosphorus supply was increased from no phosphorus or heterogeneous phosphorus (half of the phosphorus amount) to homogeneous phosphorus. Across these three conditions, the growth traits of different Eucalyptus hybrids differed significantly, indicating different adaptabilities of the hybrids to various phosphorus conditions. The growth traits of the aboveground tissues of Eucalyptus under different phosphorus conditions were largely influenced by the morphology of the underground root system. In addition, the root morphology of Eucalyptus under heterogeneous phosphorus treatment suggested that there were two mechanisms for locating nutrients. Eucalyptus hybrids such as Urophylla 3229, Grandis 9, Guanglin 3, 201-2, and Dunn produced more roots proximal to the phosphorus supply; the other hybrids, Urophylla 3216, Grandis 5, and Guanglin 9, relied mainly on the growth of roots opposite the phosphorus supply to obtain adequate nutrients for growth. With these two strategies, a wide range of nutrients was obtained, root distribution was greater, more soil volume was covered, the contact area of the roots with soil phosphorus was increased, and the uptake of phosphorus by the root system was increased. These results demonstrate that Eucalyptus relies on changes to morphological characteristics of the root system to increase accessibility to phosphorus resources. 展开更多
关键词 Eucalyptus hybrid PHOSPHORUS growth traits Root configuration
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EXPONENTIAL STABILITY FOR NONLINEAR HYBRID STOCHASTIC PANTOGRAPH EQUATIONS AND NUMERICAL APPROXIMATION 被引量:2
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作者 周少波 薛明皋 《Acta Mathematica Scientia》 SCIE CSCD 2014年第4期1254-1270,共17页
The paper develops exponential stability of the analytic solution and convergence in probability of the numerical method for highly nonlinear hybrid stochastic pantograph equation. The classical linear growth conditio... The paper develops exponential stability of the analytic solution and convergence in probability of the numerical method for highly nonlinear hybrid stochastic pantograph equation. The classical linear growth condition is replaced by polynomial growth conditions, under which there exists a unique global solution and the solution is almost surely exponentially stable. On the basis of a series of lemmas, the paper establishes a new criterion on convergence in probability of the Euler-Maruyama approximate solution. The criterion is very general so that many highly nonlinear stochastic pantograph equations can obey these conditions. A highly nonlinear example is provided to illustrate the main theory. 展开更多
关键词 stochastic pantograph equation hybrid system polynomial growth conditions exponential stability convergence in probability
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Human epidermal growth factor receptor 2 expression in mixed gastric carcinoma 被引量:4
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作者 Yang-Kun Wang Zhong Chen +7 位作者 Tian Yun Cong-Yang Li Bo Jiang Xue-Xia Lv Guang-Hui Chu Su-Nan Wang Hui Yan Lei-Feng Shi 《World Journal of Gastroenterology》 SCIE CAS 2015年第15期4680-4687,共8页
AIM: To investigate human epidermal growth factor receptor 2(HER2) amplification and protein expression in mixed gastric carcinoma.METHODS: Fluorescence in situ hybridization and immunohistochemistry were used to dete... AIM: To investigate human epidermal growth factor receptor 2(HER2) amplification and protein expression in mixed gastric carcinoma.METHODS: Fluorescence in situ hybridization and immunohistochemistry were used to detect HER2 amplification and protein expression in 277 cases of mixed gastric carcinoma. Protein staining intensity was rate as 1+, 2+, or 3+.RESULTS: Of the 277 cases, 114(41.2%) expressed HER2 protein. HER2 3+ staining was observed in 28/277(10.1%) cases, 2+ in 37/277(13.4%) cases, and 1+ in 49/277(17.7%) cases. A HER2 amplification rate of 17% was detected, of which 25/28(89.3%) were observed in the HER2 3+ staining group, 17/37(45.9%) in 2+, and 5/49(10.2%) in 1+. Of the 47 patients with HER2 amplification who received chemotherapy plus trastuzumab, 22 demonstrated median progression-free and overall survivals of 9.1 mo and 16.7 mo, respectively, which were significantly better than those achieved with chemotherapy alone(5.6 mo and 12.1 mo, respectively) in 19 previously treated patients(P s < 0.05). CONCLUSION: HER2 detection in mixed gastric carcinoma displays high heterogeneity. Relativelyquantitative parameters are needed for assessing the level of HER2 amplification and protein expression. 展开更多
关键词 Fluorescence in SITU hybridIZATION Gastricpathology Human EPIDERMAL growth factor receptor 2 IMMUNOHISTOCHEMISTRY STOMACH
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Effects of Fleckvieh on the Performance of Dual-Purpose Cattle Improved by Hybridization with Local Beef Cows
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作者 Wang Linfeng Yang Gaiqing +7 位作者 Lian Hongxia Yan Ping Liu Xian Liu Yan Wang Wenhui Zhu Ruiguang Li Ming Yang Guoyu 《Animal Husbandry and Feed Science》 CAS 2015年第6期322-326,357,共6页
[Objective] The paper aimed to study the improved effect of local beef cattle with Fleckvieh cattle and provide theoretical basic data for local cattle industry in central plain agricultural area in China. [Method] Wi... [Objective] The paper aimed to study the improved effect of local beef cattle with Fleckvieh cattle and provide theoretical basic data for local cattle industry in central plain agricultural area in China. [Method] With 500 local beef cattle as female parents and Fleckvieh cattle as male parents,hybridization improvement was conducted via artificial insemination. The growth performance,slaughter performance,milk performance and milk components of F1 and F2 hybrids were measured. [Result] The birth body weights of F2 were significantly higher than those of local beef cow,but there was no remarkable difference between F1 and local beef cow or F1 and F2. The growth rates of F1 and F2 at different stages were higher than those of local beef cattle. The slaughter performance,such as carcass weight( P < 0. 05),dressing percentage,net meat rate( P < 0. 05),marbling score of F1 and F2 were higher than those of local beef cow. Milk production performance,such as actual milk yield,305 d corrected milk yield and 4% standard milk yield of F2 were signally higher than those of F1 and local beef cattle( P< 0. 05),and F1 was markedly higher than local beef cattle( P < 0. 05). For milk composition,although milk fat percentage,milk protein rate,lactose rate and total solids( TS) of F1 and F2 were slightly lowered compared with local beef cattle at varying degrees,they were still at high levels compared with Holstein cows.[Conclusion]Fleckvieh cattle,as a male parent,can significantly improved growth performance,slaughter performance and milk performance of offsprings. It would also increases the economic efficiency of local beef cattle by higher quality and price,as well as changing production model from beef to dual purpose of beef and milk. 展开更多
关键词 Dual-purpose cattle hybridization and improvement growth performance Production performance Milk quality
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Analysis on Dry Matter Production Characteristics of Super Hybrid Rice 被引量:16
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作者 WU Wen-ge ZHANG Hong-cheng +4 位作者 QIAN ZHAI Chao-qun DAI Qi-gen Ying-fei CHENG Ye Wu Gui-cheng 《Rice science》 SCIE 2008年第2期110-118,共9页
Six middle-season indica hybrid rice combinations, including five super hybrid rice combinations with the high yield about 10.5 t/ha and a check hybrid rice combination Shanyou 63 with a yield potential about 9.5 t/ha... Six middle-season indica hybrid rice combinations, including five super hybrid rice combinations with the high yield about 10.5 t/ha and a check hybrid rice combination Shanyou 63 with a yield potential about 9.5 t/ha, were used as materials to study the dry matter production characteristics. The super hybrid rice showed a high ability in dry matter production and accumulation and its yield enhanced with the increase of dry matter accumulation. The advantage period of dry matter production in the super hybrid rice was mainly at the middle and late growth stages compared with the check. The grain yield had no significant correlation with the dry matter accumulation before the elongation stage while had a significantly positive correlation with the dry matter accumulation from the elongation to maturity stages in super hybrid rice. There were more dry matter in vegetative organs at the heading stage in the super hybrid rice but its contribution to yield (apparent conversion percentage) was averagely 4.3 percent points lower than that in the check. For crop growth rate (CGR), the comparative advantage of super hybrid rice was at the middle and late stages, especially after flowering. Moreover, as the rising of leaf area index (LAI) and leaf area duration (LAD), CGR enhanced. The total LAD and the mean of lAD per day of super hybrid rice was about 14.79% and 10.31% higher than those of the check, respectively. The results indicate that the high yield of super hybrid rice mostly comes from the products of photosynthesis after heading, which is shown by the increased CGR at middle and later stages. It is suggested that LAD character might be used to better explain the advantage in the dry matter production of super hybrid rice than LAI. 展开更多
关键词 super hybrid rice dry matter production crop growth rate leaf area duration leaf area index net assimilation rate
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江淮地区苜蓿短期连作对后作高丹草生长及土壤微环境的影响
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作者 李争艳 徐智明 +1 位作者 李岩 李杨 《草业学报》 CSCD 北大核心 2024年第9期155-168,共14页
为了探究苜蓿连作对后作高丹草产量品质及土壤健康状况的影响,分别以撂荒地正茬种植高丹草(yr_(0))为对照、苜蓿1年龄(yr_(1))、3年龄(yr_(3))、5年龄(yr_(5))后轮作高丹草3种处理方式为研究对象,采用传统方法,试剂盒及高通量测序方法... 为了探究苜蓿连作对后作高丹草产量品质及土壤健康状况的影响,分别以撂荒地正茬种植高丹草(yr_(0))为对照、苜蓿1年龄(yr_(1))、3年龄(yr_(3))、5年龄(yr_(5))后轮作高丹草3种处理方式为研究对象,采用传统方法,试剂盒及高通量测序方法检测了轮作后高丹草的生长状况及产量差异、轮作后土壤化学性质、酶活性及微生物结构组成的变化,阐明了苜蓿短期连作对后作高丹草生长及产量的影响,从土壤微环境的角度评价了苜蓿连作对后作高丹草的影响。研究结果显示,与正茬高丹草相比(yr_(0)),苜蓿轮作高丹草促进了后茬高丹草叶片数量及产量的增加,3年龄苜蓿(yr_(3))轮作高丹草与正茬(yr_(0))高丹草相比,后作高丹草产量增加了63.23%(P<0.05),粗蛋白及中性洗涤纤维含量也相应提高;后作高丹草土壤pH值随着前作苜蓿年龄的增加持续降低,土壤有机质、全氮含量持续增加,5年龄(yr_(5))苜蓿轮作高丹草后有机质含量比正茬高丹草(yr_(0))土壤增加了78.25%、全氮含量与正茬高丹草(yr_(0))土壤相比增加了34.88%(P<0.05);蔗糖酶活性在1年龄(yr_(1))苜蓿轮茬高丹草土壤中最高,脲酶在3年龄(yr_(3))后茬土壤中活性最高;在苜蓿轮作高丹草根际土壤中门水平优势细菌群落为变形菌、拟杆菌和厚壁菌,优势真菌群落为子囊菌、担子菌和聚合菌;前茬苜蓿3年龄(yr_(3))时轮作高丹草土壤细菌丰富度及多样性指数均为最高(P<0.05);前茬苜蓿5年龄(yr_(5))时轮作高丹草土壤真菌Shannon指数最高(P<0.05);苜蓿轮作高丹草土壤中的绿弯菌、浮霉菌、放线菌随着前作苜蓿年龄的增加呈先增加随后降低的变化趋势;相关性分析表明,土壤pH、有机质含量与土壤微生物结构关系紧密,苜蓿-高丹草轮作处理下,前作苜蓿分泌物和残体降解物进入土壤生态系统,加速特异微生物区系重构,缓解了土壤酸化及调整营养物质循环,具有改良土壤的作用,能够促产增效,但是种植年限不宜过久,种植年限超过3年后,土壤中的营养成分会打破平衡。该结果为江淮地区苜蓿连作障碍的生态修复,构建饲草可持续高效生产栽培关键技术体系提供了理论依据。 展开更多
关键词 苜蓿-高丹草轮作 高丹草生长 微生物群落结构 土壤环境
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Expression of Vascular Endothelial Growth Factor in Bone Morphogenetic Protein-2 Induced Osteogenesis 被引量:5
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作者 傅德皓 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2005年第B12期118-122,共5页
An experimental model of femoral muscular pouch in 20 mice was adopted. The expression of VEGF was examined by in situ hybridization method and immunohistochemical method in bone morphogenetic protein- 2 induced osteo... An experimental model of femoral muscular pouch in 20 mice was adopted. The expression of VEGF was examined by in situ hybridization method and immunohistochemical method in bone morphogenetic protein- 2 induced osteogenesis . The experimental results demonstrated that the expression signals of VEGF mRNA and VEGF appeared in cytoplasm during condensation of mesenehymal cell. As the mesenchymal cells differentiated into precartilage, the expression signals decreased in mesenehymal cells, but increased in chondrocytes and kept getting denser in the process of cartilage maturity. The peak expression of VEGF mRNA and VEGF in the experimental group appeared on the 14 th day, accompanied by numerons hypertrophic chondrocytes. When mature cartilage calcified and neu, bone trabecula formed, the expression of VEGF mRNA and VEGF decreased in chondrocytes, but still expressed moderately in the osteoblasts and osteocytes. Signals of VEGF mRNA and VEGF can not be detected in the control groups. 展开更多
关键词 bone morphogenetic protein vascular endothelial growth factor gene expression in situ hybridization IMMUNOHISTOCHEMISTRY
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杂交导入巴克夏血统对苏紫猪生长育肥性状的影响分析
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作者 付言峰 廖超 +3 位作者 王学敏 涂枫 李碧侠 程金花 《畜牧与兽医》 CAS 北大核心 2024年第8期21-25,共5页
为了探讨含不同巴克夏猪(巴克夏)血统含量(0、25%、50%)的苏紫猪生长育肥性状有无显著改善,选取68头不同类型的苏紫猪,初始体重在30 kg左右,采用全自动种猪生产性能测定系统进行分批次测定。结果显示:试验共获得130700条有效采食和称重... 为了探讨含不同巴克夏猪(巴克夏)血统含量(0、25%、50%)的苏紫猪生长育肥性状有无显著改善,选取68头不同类型的苏紫猪,初始体重在30 kg左右,采用全自动种猪生产性能测定系统进行分批次测定。结果显示:试验共获得130700条有效采食和称重数据,深入分析后发现不同巴克夏血统含量的苏紫猪达相关体重的日龄不同,达60 kg和90 kg体重日龄均为含50%巴克夏血统苏紫猪最大,显著大于无巴克夏血统苏紫猪(P<0.05)。30~60 kg生长阶段的日增重,含25%巴克夏血统和无巴克夏血统苏紫猪显著高于含50%巴克夏血统苏紫猪(P<0.05);30~90 kg和30~110 kg生长阶段的日增重,均为无巴克夏血统苏紫猪最高,显著高于含50%巴克夏血统苏紫猪(P<0.05)。30~90 kg和30~100 kg生长阶段的料重比,均为含50%巴克夏血统苏紫猪最低,且显著低于含25%巴克夏血统和无巴克夏血统苏紫猪(P<0.05)。结论:杂交导入巴克夏血统对苏紫猪的生长速度提升不显著,但对其料重比的改善显著,其中含25%巴克夏血统的苏紫猪生长性能比较均衡,未来可以进行优先培育。 展开更多
关键词 生长 育肥 性能 杂交导入
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Boosting Achene Yield and Yield Related Traits of Sunflower Hybrids through Boron Application Strategies
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作者 Imran Khan Shakeel Ahmad Anjum +3 位作者 Rashad Waseem Khan Qardri Muqarrab Ali Muhammad Umer Chattha Muhammad Asif 《American Journal of Plant Sciences》 2015年第11期1752-1759,共8页
Effects of different boron (B) application methods on growth and yield of sunflower hybrids were checked out at Agronomic Research Farm, University of Agriculture, Faisalabad, Pakistan during spring, 2013. Field exper... Effects of different boron (B) application methods on growth and yield of sunflower hybrids were checked out at Agronomic Research Farm, University of Agriculture, Faisalabad, Pakistan during spring, 2013. Field experiment was conducted by considering three sunflower hybrids viz., Patron 551, Patron 851 and S-278 along with different methods of B application i.e. no B application, seed treatment @ 0.05% B, soil B application @ 2 kg·ha-1 at sowing, soil B application @ 2 kg·ha-1 at ray floret stage and foliar application of B @ 200 mg·L-1 at ray floret stage. Uttermost plant height (150.78 cm), the number of leaves per plant (22.67) and stem diameter (1.62 cm) were accomplished when boron was soil applied @ 2 kg·ha-1 at sowing. Significantly higher head diameter (18.30 cm), number of achene per head (1266.44), 1000-achene weight (43.17 g) achene yield (2039.33 kg·ha-1), biological yield (9223.11 kg·ha-1) and harvest index (22.10%) were registered when boron was foliar applied @ 200 mg·L-1 at ray floret stage. Among sunflower hybrids, Patron 551 produced significantly higher growth and yield attributes as compared with Patron 851 and S-278 hybrids. This study suggested that the selection of Patron 551 hybrid with practicing boron foliar application @ 200 mg·L-1 at ray floret stage could be helpful in achieving the sunflower crop genetic potential. 展开更多
关键词 BORON Application Methods SUNFLOWER hybridS Biological YIELD ACHENE YIELD growth and YIELD Attributes
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The Effect of Simvastatin on mRNA Expression of Transforming Growth Factor-β1,Bone Morphogenetic Protein-2 and Vascular Endothelial Growth Factor in Tooth Extraction Socket 被引量:10
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作者 Chang Liu Zhe Wu Hong-chen Sun 《International Journal of Oral Science》 SCIE CAS CSCD 2009年第2期90-98,共9页
Aim To determine the effect of local simvastatin application on the mRNA expression level of transforming growth factor-β1 (TGF-β1), bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (... Aim To determine the effect of local simvastatin application on the mRNA expression level of transforming growth factor-β1 (TGF-β1), bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF) in the tooth sockets of rat. Methodology Forty-eight male Wistar rats were randomly divided into experimental and control groups (n=24). Polylactic acid/polyglycolic acid copolymer carriers, with or without simvastatin, were implanted into extraction sockets of right mandibular incisors. The expression of TGF-β1, BMP-2 and VEGF mRNA was determined by in situ hybridization in the tooth extraction socket at five days, one week, two weeks and four weeks after implantation. Results The fusiform stroma cells in the tooth extraction socket began to express TGF-β1, BMP-2 and VEGF mRNA in both experimental and control groups from one week after tooth extraction until the end of experiment. The expression of TGF-131 and BMP-2 mRNA in the experimental group was significantly up-regulated after one, two and four weeks, and expression of VEGF mRNA was significantly increased after one and two weeks compared with that in the control group. Conclusion The findings indicate that local administration of simvastatin can influence alveolar bone remodeling by regulating the expression of a school of growth factors which are crucial to osteogenesis in the tooth extraction socket. 展开更多
关键词 bone morphogenetic protein-2 (BMP-2) in situ hybridization SIMVASTATIN tooth extraction socket transforming growth factor-β1 (TGF-β1) vascular endothelial growth factor (VEGF)
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弗莱维赫牛改良荷斯坦牛的杂交F1代生长性能研究
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作者 杨阳 叶翠芳 +5 位作者 李广 陈爱江 王刚 景磊 王德泽 欧四海 《中国乳业》 2024年第3期23-28,共6页
[目的]对比研究弗莱维赫牛改良荷斯坦牛的杂交代在生长过程中的发育性状优势,通过选种培育适合奶牛养殖场的乳肉兼用新品种牛。[方法]测定杂交F1代和荷斯坦青年牛出生到25月龄的体重、体尺,进行对比研究。[结果]杂交F1代牛在不同月龄的... [目的]对比研究弗莱维赫牛改良荷斯坦牛的杂交代在生长过程中的发育性状优势,通过选种培育适合奶牛养殖场的乳肉兼用新品种牛。[方法]测定杂交F1代和荷斯坦青年牛出生到25月龄的体重、体尺,进行对比研究。[结果]杂交F1代牛在不同月龄的生长发育比荷斯坦牛均快,最显著的是20月龄,虽然出生体重小2.8 kg,但20月龄体重多76 kg,日增重多0.16 kg,体斜长、胸围、胸深、尻宽分别多13 cm、8 cm、2cm、2 cm,尻长无差异。[结论]杂交F1代的日增重、体斜长、胸围、胸深、尻宽生长发育都优于荷斯坦牛,具备弗莱维赫牛生长快、增重快的品种优势。 展开更多
关键词 弗莱维赫牛 荷斯坦牛 杂交F1代 生长性能
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Accurate Assessment of HER2 Gene Status for Invasive Component of Breast Cancer by Combination of Immunohistochemistry and Chromogenic In Situ Hybridization
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作者 聂秀 贺骏 +6 位作者 李燕 潘丹珍 潘华雄 翁密霞 杨秀萍 刘春萍 黄韬 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2013年第3期379-384,共6页
Summary: The specimens of ductal carcinoma in situ (DCIS) with early invasion, and specimens col- lected by core needle biopsy (CNB) tend to contain limited amount of invasive component, so it is im- perative to ... Summary: The specimens of ductal carcinoma in situ (DCIS) with early invasion, and specimens col- lected by core needle biopsy (CNB) tend to contain limited amount of invasive component, so it is im- perative to explore a new technique which can assess HER2 gene status accurately for the limited inva- sive cancer component in these specimens. Dual staining technique of combining immunohistochemis- try (IHC) for myoepithelial cells and single or dual probe chromogenic in situ hybridization (CISH) for HER2 gene was performed on routinely processed paraffin sections from 20 cases diagnosed as having DCIS with invasive cancer. Among them, 10 had fluorescence in situ hybridization (FISH)-confirmed amplification of HER2 and 10 had FISH-confirmed non-amplification of HER2. We successfully de- tected HER2 genetic signals and myoepithelial IHC markers (SMM-HC or CK5/6) simultaneously on a single section in all 20 specimens. Myoepithelial markers and HER2 signals detected by dual staining assay were consistent with those by individual technique performed alone. HER2 gene amplification results determined by dual staining assay were 100% consistent with those of FISH. Dual staining tech- nique which allows simultaneous detection of myoepithelial marker protein and cancerous HER2 gene is feasible, and it has potential to be used in clinical practice for effective determination of HER2 ampli- fication in limited invasive component. 展开更多
关键词 human epidermal growth factor receptor 2 chromogenic in situ hybridization immunohis- tochemistry
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肉羊不同杂交组合生长曲线模型筛选及分析 被引量:1
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作者 沈嘉玘 孙渭博 +8 位作者 施海娜 梁永虎 杨博辉 岳耀敬 袁超 郭婷婷 文亚洲 卢曾奎 张利平 《家畜生态学报》 北大核心 2024年第2期28-32,96,共6页
为研究肉羊不同杂交组合生长发育规律及评价适宜推广的杂交模式,以引进品种澳洲白、杜泊和萨福克羊为父本,湖羊为母本进行杂交试验。测定不同杂交组合1~6月龄体重,利用Brody、Logistic、Gompertz和Von Bertalanffy 4种模型分别拟合各杂... 为研究肉羊不同杂交组合生长发育规律及评价适宜推广的杂交模式,以引进品种澳洲白、杜泊和萨福克羊为父本,湖羊为母本进行杂交试验。测定不同杂交组合1~6月龄体重,利用Brody、Logistic、Gompertz和Von Bertalanffy 4种模型分别拟合各杂交组合体重发育过程,分析体重参数和模型估计值,评价杂交优势。结果表明:4种模型的拟合度(R^(2))均在0.95以上,其中Von Bertalanffy模型估计值最接近各个杂交组合的实测值,拟合效果最佳,拐点体重介于7.64~9.98 kg之间,拐点日龄在25~35 d之间。澳湖、杜湖和萨湖3个杂交组合最大日增重均在200 g左右(P>0.05),表明三者体重发育相近且适宜推广。Von Bertalanffy模型符合杂交羔羊体重实际生长现状,可为杂交羔羊早期体重发育评估提供依据。 展开更多
关键词 肉羊 杂交组合 体重 生长曲线模型 拟合分析
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