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Apoptosis of Primordial Germ Cells

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Apoptosis of Primordial Germ Cells

中国细胞生物学学会2005.学术大会、青年学术研讨会

作者： Hua Jinlian,Lei Anmin,Xu Xiaoming ,Dou Zhongying, Shaanxi Centre of Stem Cells Engineering & technology,northwest sci-tech {4. of {5. & forestry,yangling 712.00

Primordial germ cells (PGCs) are the progenitor cells of spermatocytes of testis or oogoniums of ovary. Apoptotic develop in germ cell development during the prenatal and postnatal period, and in vitro culture PGCs. Fas system, Bcl-x1, Bcl-2, c-myc、 Ice、 c-Kit/ SCF and mitochondrion mutations and other play an important role in the control of apoptosis in germ cell development. Mouse and porcine PGCs cultured in vitro showed the typical characteristics of apoptosis. PGCs cultured in vitro underwent apoptosis, the nucleus showed distinct chromatin condensation and fragmentation, then form apoptotic bodies, as well as extensive degradation of DNA. Leukemia inhibitory factor (LIF), basic fibroblast growth factor (bFGF), stem cell factor (SCF) and other cytokines, fibronectin, laminin and other extracellular matrix, feeder cells could inhibit the apoptosis of PGCs in vitro culture, are bebefical to the survival and proliferation. α2-macroglobulin(MAC) is a broad range protease inhibitor can inhibit PGCs apoptosis in vitro, which inhibit the enzymes involved in apoptosis.β2-mercaptoethanol(BME), N-acetylcysteine(NAC), glutathione(GSH) and othe antioxidant could reduce oxidative stress and prevent apoptosis of PGCs and embryonic stem cells.

关键词： Apoptosis of Primordial Germ Cells SCF

Soil NH_4.+ Fixation and Fertilizer N Recovery as Affected by Soil Moisture and Fertilizer Application Methods

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Pedosphere 2004年第2期14卷 247-252页

作者： TONGYan-Ani O.EMTERYD H.GRIP LUDian-Qing CollegeofResourceandEnvironment NorthwestSci-TechUniversityofAgricultureandForestryStateKeyLaboratoryofSoilErosionandDrylandFarmingintheLoessPlateauYanglingShaanxi712100（China）.Email：tongyanan@*** DepartrnentofForestEcology SwedishUniversityofAgriculturalSciencesUrneaS-90183（Sweden）

Ammonium fixation and the effects of soil moisture and application methods on fertilizer N recovery were investigated in two soils of Shaanxi Province,China,a Luvisol and an Entisol,through two experiments performed in the laboratory and in a glass shelter,respectively,by using ammonium bicarbonate (NH4.CO3). The laboratory closed incubation box experiment was conducted using the Luvisol to study NH4. fixation rate at soil moisture levels of 10.1%,22.7% and 35.3% water filled pore space (WFPS). The fixed NH4.-N increased dramatically to 5.% and 66%,67% and 74.,and 82% and 85. 1,2 and 36 h after fertilizer incorporation at moisture levels of 10.1% and 22.7% WFPS and 35.3%WFPS,respectively. The rapid NH4. fixation rates at all moisture levels could help prevent NH4. losses from ammonia volatilization. In the glass shelter pot experiment,N fertilizer was applied by either banding (in a concentrated strip)or incorporating (thoroughly mixing) with the Entisol and the Luvisol. An average of 74.2% of the added N fertilizer was recovered 26 days after application to the Luvisol,while only 61.4. could be recovered from the Entisol,due to higher NH4. fixation capacity of the Luvisol. The amount of fixed NH4. decreased with increasing WFPS. The amount of fixed NH4. in the incorporated fertilizer treatment was,on average,10% higher than that in the banded *** NH4. fixation rates could prevent N loss and thus increase N recovery. The results from the Luvisol showed lower nitrogen recovery as soil moisture level increased,which could be explained by the fact that most of the fixed NH4. was still not released when the soil moisture level was low. When the fertilizer was incorporated into the soil,the recovery of N increased,compared with the banded treatment,by an average of 26.2% in the Luvisol and 11.2% in the Entisol,which implied that when farmers applied fertilizer,it would be best to mix it well with the soil.

关键词： fertilizer application N recovery NH4. fixation soil moisture

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文献信息资源共享的博弈分析

图书情报工作 2003年第8期47卷 35-38页

作者：白君礼李志俊西北农林科技大学图书馆杨凌712100 长安大学小寨校区图书馆西安710061

运用博弈论观点对文献信息资源共享发展缓慢的原因进行分析。指出在文献信息资源共享过程中存在着“囚徒困境”,它使每个图书馆受益的文献信息资源量和利润下降。

关键词：文献信息资源资源共享博弈论图书馆库诺特均衡纳什均衡 “囚徒困境”

SEVERAL sciENTIFIC PROBLEMS ON ECOLOGICAL SAFETY AND AGRICULTURAL SUSTAINABLE DEVELOPMENT IN WEST CHINA

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Natural Disaster Reduction in China 2002年第2期 25-29页

作者： Yang Zhengli 1, Yang Gaihe 1 and Zhang Dapeng 2 (1.northwest sci tech university of {4. and {5., yangling 712.00, Shaanxi, China 2.Station of Soil and Manure, Department of {4., Shaanxi, 710000, China)

The article addresses several scientific issues regarding the ecological safety and agricultural sustainable development in the west of China from the perspectives of system ecology and system eco economics, including the relationship between agricultural development and ecological construction, development based ecological balance, the relationship between ecological agriculture and agricultural modernization, and ecological rehabilitation.

关键词： ecological safety agricultural sustainable development ecological rehabilitation west China

Regulation of Propylene and 1-Methylcyclopropene on Expressions of ACS and ACO Genes in Persimmon Fruits

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Agricultural sciences in China 2009年第10期8卷 1187-1192页

作者： LIU Le, RAO Jing-ping, CHANG Xiao-xiao and YI Shun-chao College of Horticulture, northwest Agricultural and Forest university/Key Laboratory of northwest Horticultural Plants Germplasm and Genetic Improvement, Ministry of agriculture,{4., P.R.China [a]College of Horticulture Northwest Agricultural and Forest University/Key Laboratory of Northwest Horticultural Plants Germplasm and Genetic Improvement Ministry of Agriculture Yangling 712100 P.R. China

The regulation of postharvest treatment with propylene and 1-MCP on ethylene release rate and expressions of 1- aminocyclopropane-l-carboxylic acid synthase （ACS） and 1-aminocyclopropane-1-carboxylic acid oxidase （ACO） genes in Fuping Janshi persimmon （Diospyros kaki L.） fruit were investigated. Fruits were treated with propylene and 1-MCP, then stored at 20℃, ethylene release rate of the treated fruits was measured at regular intervals and RNA was extracted for Northern blotting analysis. The results suggested that treatment with propylene accelerated the expressions of ACS and ACO genes and then enhanced the ethylene biosynthesis, while treatment with 1-MCP inhibited the expressions of two genes and their ethylene biosynthesis. Furthermore, different effects on expressions caused by treatments with propylene and 1-MCP existed in various fruit tissues, the inhibitory effect on ACS and ACO genes by 1-MCP was the strongest in pericarp, followed by pulp and core tissues, in the area near fruit stalk, the inhibitory effect was the weakest. While the enhanced effect on ACS and ACO genes by propylene increased from pulp, core, and pericarp to the area near fruit stalk. Expression of each member of ACS and ACO families in various tissues was also completely different, in control and propylene treatment, DKACS3 gene just expressed in the area near fruit stalk and did not express in other tissues, but DKACS2 gene expressed in four tissues by treatment with propylene.

关键词： persimmon (Diospyros kaki L.) propylene 1-MCP ACS ACO

The EST Analysis of A Suppressive Subtraction cDNA Library of Chinese Wild Vitis pseudoreticulata Inoculated with Uncinula necator

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Agricultural sciences in China 2010年第2期9卷 233-241页

作者： SHI Jiang-li, WANG Yue-jin, ZHU Zi-guo and ZHANG Chao-hong Key Laboratory of Horticultural Plant Germplasm Utilization in northwest China, Ministry of agriculture/Shaanxi Key Laboratory of Molecular Biology for agriculture/College of Horticulture, northwest A&F{4.,{5., P.R.China [a] Key Laboratory of Horticultural Plant Germplasm Utilization in northwest China Ministry of Agriculture/Shaanxi Key Laboratory of Molecular Biology for Agriculture/College of Horticulture Northwest A&F University Yangling 712100 P.R. China

Uncinula necator is a worldwide serious fungus disease causing annual heavy lost on grapevine production. In order to get more informations on defense related EST sequences and help breeding program, we constructed and characterized a suppression subtractive hybridization cDNA library with artificially inoculated leaves and control Chinese wild Vitis pseudoreticulata clone Baihe-35.1, which is highly resistant to powdery mildew. In the library, the length of 5. EST fragments known as putative functions varied from 130 to 800 bp, and 60% of the ESTs exhibited high similarity to known sequences in database of GenBank with BLASTX analysis. These genes were involved in stress/defense response, detoxification, signal transduction, disease defense, and etc., and 14.ESTs remained unknown or hypothetical proteins, which may be new genes. The experiment provided an important basis for studying the disease-resistance mechanism and obtaining the genes for the aim of improving grapevine powdery mildew resistance.

关键词： Chinese wild Vitis pseudoreticulata disease resistance SSH cDNA library EST sequence

Biological active metabolites from the Chinese higher fungi

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Biological active metabolites from the Chinese higher fungi

The 3～(rd) International Conference on Natural Products :Natural Products -a Must for Human Survival ABSTRACTS

作者： Jinming Gao Division of Natural Products Chemistry, northwest sci-tech university of {4. and {5., yangling 712.00, Shanxi, China National Engineering Research Center for Phytochemistry in West China, yangling 712.00, China

Higher fungi, so called mushrooms, are characterized by the production of macroscopic fruiting bodies to generate and to distribute their spores. There are approximately 10,000 species of higher fungi known up to now in China. Higher fungi are the more productive biosource of a large and diversified variety of secondary metabolites. Much attention was paid to the different activities of these metabolites and the attempts were made to use them in medicinal and agricultural chemistry. Mushrooms have been consumed by humans since ancient times not only as a part of the normal diet but also as a delicacy due to their desirable taste and aroma. The use of mushrooms with therapeutic properties is growing more and more due to the range of side effects caused by conventional medicines. Among natural products, mushrooms have been recognized as potent candidates in clinical studies because they are readily obtained in relatively large quantities and are *** the past decades, the chemical constituents with bioactivities from the fruiting bodies and mycelial cultures of the Chinese higher fungi, twenty-seven Basidiomycetes and four Ascomycetes species, have been investigated. The overview is to describe the isolation, structure elucidation and interesting biological properties of different types of terpenoids, sphingolipids, phenolics and nitrogenous compounds. Overall, 86 structures are presented and the review contains 65.references.

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Using REE Tracers to Measure Sheet Erosion Changing to Rill Erosion

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Using REE Tracers to Measure Sheet Erosion Changing to Rill ...

中国原子能农学会第七次代表大会暨学术研讨会

作者： Liu Puling, Xue Yazhou, Song Wei, Yang Mingyi, Ju Tongjun(State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Water and Soil Conservation, Chinese Academy of sciences and Ministry of Water Resources northwest sci-tech {4. of {5. and forestry, yangling 712.00, China)

＜正＞ Rare Earth Elements（REE） tracer method was used to study sheet erosion changing to rill erosion onslope land. By placing different rare earth elements of different soil depth across a slope in an indoor plot, twosimulated rainfalls were applied to study the change of erosion type and the rill erosion process. The resultsindicate that the main erosion type is sheet erosion at the beginning of the rainfalls, and serious erosion happensafter rill erosion appears. Accumulated sheet and rill erosion amounts increase with the rainfalls time. Thepercentage of sheet erosion amount decreases and rill erosion percentage increases with time. At the end of therainfalls, the total rill erosion amounts are 4.- 5.times more than sheet erosion. In this paper, a new REE tracermethod was used to quantitatively distinguish sheet and rill erosion amounts. The new REE tracer method shouldbe useful to future studying of erosion processes on slope lands.

关键词： soil erosion erosion type change REE tracer method slope land

Assessing and regulating the impacts of climate change on water resources in the Heihe watershed on the Loess Plateau of China

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science China Earth sciences 2010年第5期53卷 710-720页

作者： LI Zhi1,2, LIU WenZhao2, ZHANG XunChang3 & ZHENG FenLi2 1 College of Resources and Environment, northwest agriculture & forestry university,{4., China 2 Institute of Soil and Water Conservation, Chinese Academy of {5.ences & Ministry of Water Resources,{4., China 3 USDA-ARS Grazinglands Research Laboratory, 73036, El Reno, Oklahoma, USA 1. College of Resources and Environment Northwest Agriculture & Forestry University Yangling 712100 China2. Institute of Soil and Water Conservation Chinese Academy of Sciences & Ministry of Water Resources Yangling 712100 China3. USDA-ARS Grazinglands Research Laboratory El Reno Oklahoma 73036 USA

Climate change can cause considerable changes in water resources and assessing the potential impacts can provide important information for regional sustainable development. The objectives were to evaluate the possible impacts of climate change during 2010-2039 on water resources (runoff, soil water content, and evapotranspiration) in the Heihe watershed on the Loess Plateau of China and to further explore adaptive measures to cope with the changes. Projections of four climate models (CCSR/NIES, CGCM2, CSIRO-Mk2, and HadCM3) under three emission scenarios (A2, B2, and GGa) were used to estimate future changes in precipitation, maximum and minimum temperature based on Change Factor method. The Soil and Water Assessment Tool (SWAT) was employed to simulate the hydrologic responses to climate changes. The CA-Markov model was used to develop land use scenarios. Compared with the present climate, the climate models predicted a -2.3% to 7.8% change in annual precipitation, 0.7 to 2.2°C rises in maximum temperature, and 1.2 to 2.8°C rises in minimum temperature. Without consideration of land use change, SWAT predicted a -19.8% to 37.0% change for runoff, -5.5. to 17.2% change for soil water content, and 0.1% to 5.9% increase for evapotranspiration during 2010–2039 under all climate scenarios. Though the change of hydrometeorolocial variables are complex, they would possibly increase with great probability, and the hydrological regime would be influenced such as a decrease in runoff in winter months. With land use changes, the projected land use of 2015.would increase soil water content by 4.0% and surface runoff by 5.7% while slightly decrease evapotranspiration by 0.6% compared with the 2000 land use. This result showed that adjustment of land use patterns was capable of regulating water resources and could be used to mitigate the adverse effects of climate change.

关键词： climate change water resources SWAT the Loess Plateau