辽西半干旱地区深松中耕对作物产量的影响及其作用机理研究

对辽宁西部半干旱地区深松中耕对作物产量影响及作用机理的研究表明,深松打破了犁底层,减小了土壤容重及穿透阻力,增加了表层及亚表层土壤的孔隙度．深松土壤水分人渗可达８０ｃｍ,大豆根系深度增加３．６～４．０ｃｍ,大豆产量和水分利用效率分别增加２７．７～３４．５％和１６．１％,在干旱年份玉米增产７．９％．     

不同科属来源的六株Frankia代表菌株碳源利用谱的研究

对来自赤杨属、木麻黄属、异木麻黄属、沙棘属和杨梅属的六株Frankia代表菌株进行了二十四种碳源利用谱的比较研究(包括简单有机酸、单糖、双糖、三糖和糖醇在内)。结果表明,各菌株在碳源利用种类和程度上有明显差异;简单有机酸盐特别是丙酸钠是所有菌株的良好碳源;菌株Cc01、A11I1和Hr16还能很好地利用丙酮酸钠;除了菌株Hr16能很好地利用纤维二糖,菌株A11I1利用葡萄糖外;糖醇类很少被利用。如果以丙酮酸钠、丙酸钠和乙酸为“诊断性”碳源,则可以将供试菌株分为三个类群,即赤杨——杨梅类群、沙棘类群和木麻黄类群;这与交叉接种和血清学方法得出的结论相吻合。     

水杉愈伤组织诱导及植株再生

通过愈伤组织诱导器官发生途径,建立了水杉（Metasequoia glyptostroboides）的植株再生体系,探讨了不同外植体（种胚、幼叶切块、茎段、根段）和植物生长调节剂对不定芽直接再生和愈伤组织诱导器官发生的影响。结果表明：以种胚、无菌苗叶片、茎段和根作为外植体,在MS补加2,4-D、NAA和6-BA不同组合的培养基上都能诱导得到愈伤组织,其中种胚诱导愈伤组织效果最好,诱导率可达100%,茎诱导效果次之,诱导率为97.1%。诱导愈伤组织效果较好的培养基有：MS＋1.0mg·L-12,4-D＋0.5mg·L-16-BA、MS＋0.1mg·L-16-BA＋1.0mg·L-1NAA、MS＋0.5mg·L-16-BA＋1.0mg·L-1NAA、MS＋1.0mg·L-16-BA＋1.0mg·L-1NAA、MS＋0.5mg·L-16-BA＋2.0mg·L-1NAA、MS＋1.0mg·L-16-BA＋2.0mg·L-1NAA和MS＋0.5mg·L-12,4-D＋0.5mg·L-1NAA。以愈伤组织在MS培养基上植株再生效果最好,再生率为62.5%。     

Integrated soil and plant phosphorus management for crop and environment in China. A review

In semi-arid grassland ecosystems, soil biogeochemical processes are controlled by seasonal and inter-annual rainfall variation and temperature, which may override the long-term impact of grazers on N availability and N dynamics. In a three-year (2004?C2006) case study of an Inner Mongolian grassland, we analysed time-integrated (ion-exchange resins) and instantaneous (soil mineral N extractions) inorganic N availability at three sites of varying grazing intensities and combined these data with information on soil water content (SWC), aboveground net primary productivity (ANPP) and plant N uptake. Additionally, the effects of rainfall and grazing on N-form availability (NO ₃ ^? -N, NH ₄ ⁺ -N) were considered. Grazing had less impact on N availability compared to seasonal and annual rainfall distribution. One of the three study years (2004) showed a grazing effect with higher resin-N availability at the ungrazed site compared to the heavily grazed site. Inorganic N availability was low in the driest year (2005) and highest in a year of average rainfall amount and favourable distribution (2004). In general, we found a positive relationship between inorganic N availability and both plant productivity and plant N uptake. Rainfall also controlled the plant available NO ₃ ^? -N and NH ₄ ⁺ -N pools; NH ₄ ⁺ -N dominated the available inorganic N-form in times of low SWC, while the available NO ₃ ^? -N increased with SWC. We observed N availability and plant productivity in a temporal synchronized pattern. Increased rainfall variability and land-use practices affecting SWC will likely alter N availability dynamics (and the relation of N-forms) and, therefore, important processes of semi-arid natural grassland carbon and N cycling.     

Histochemical examination of cathepsin K,MMP1 and MMP2 in compressed periodontal ligament during orthodontic tooth movement in periostin deficient mice

The purpose of this study was to investigate immunolocalization of collagenolytic enzymes including cathepsin K, matrix metalloproteinase (MMP) 1 and 2 in the compressed periodontal ligament (PDL) during orthodontic tooth movement using a periostin deficient (Pn-/-) mouse model. Twelve-week-old male mice homozygous for the disrupted periostin gene and their wild type (WT) littermates were used in these experiments. The tooth movement was performed according to Waldo’s method, in which elastic bands of 0.5 mm thickness were inserted between the first and second upper molars of mice under anesthesia. At 1 and 3 days after orthodontic force application, mice were fixed with transcardial perfusion of 4 % paraformaldehyde in 0.1 M phosphate buffer (pH 7.4), and the first molars and peripheral alveolar bones were extracted for histochemical analyses. Compared with WT mice, immunolocalization of cathepsin K, MMP1 and MMP2 was significantly decreased at 1 and 3 days after orthodontic tooth movement in the compressed PDL of Pn-/- mice, although MMP1-reactivity and MMP2-reactivity decreased at different amounts. Very little cathepsin K-immunoreactivity was observed in the assessed regions of Pn-/- mice, both before and after orthodontic force application. Furthermore, Pn-/- mice showed a much wider residual PDL than WT mice. Taken together, we concluded that periostin plays an essential role in the function of collagenolytic enzymes like cathepsin K, MMP1 and MMP2 in the compressed PDL after orthodontic force application.     

Quantitative protein profiling using two-dimensional gel electrophoresis,isotope-coded affinity tag labeling,and mass spectrometry

Quantitative protein profiling is an essential part of proteomics and requires new technologies that accurately, reproducibly, and comprehensively identify and quantify the proteins contained in biological samples. We describe a new strategy for quantitative protein profiling that is based on the separation of proteins labeled with isotope-coded affinity tag reagents by two-dimensional gel electrophoresis and their identification and quantification by mass spectrometry. The method is based on the observation that proteins labeled with isotopically different isotope-coded affinity tag reagents precisely co-migrate during two-dimensional gel electrophoresis and that therefore two or more isotopically encoded samples can be separated concurrently in the same gel. By analyzing changes in the proteome of yeast (Saccharomyces cerevisiae) induced by a metabolic shift we show that this simple method accurately quantifies changes in protein abundance even in cases in which multiple proteins migrate to the same gel coordinates. The method is particularly useful for the quantitative analysis and structural characterization of differentially processed or post-translationally modified forms of a protein and is therefore expected to find wide application in proteomics research.     

Antitumor mechanism of Se-containing polysaccharide, a novel organic selenium compound

Recent studies on the inhibition of tumor growth by Se-containing polysaccharide were reviewed. Meanwhile, the possible molecular mechanisms of the inhibition of tumor cell growth through antioxidation, induction of tumor cell apoptosis, blockade of cell cycle, and enhancement of immunity by Se-containing polysaccharide were proposed. In the end, the potential application of Se-containing polysaccharide in the prevention and treatment of tumor was elucidated.     

海洋芽孢杆菌（Bacillus marinus）B-9987菌株抑制病原真菌机理的研究

摘要：【目的】：探讨海洋芽孢杆菌（Bacillus marinus）B-9987菌株的代谢产物BMME-1,对植物病原真菌茄链格孢菌的抑菌作用机理。【方法】分别使用分光光法、气相色谱-质谱GC-MS联用技术、红外光谱法等,检测了BMME-1处理病原真菌后,菌体渗透性、细胞壁及细胞膜成份的变化。【结果】BMME-1对茄链格孢菌的抑菌中浓度（MIC50）为6.2 mg/L,最小杀菌浓度（MFC）为50 mg/L,在MIC50浓度或高于此浓度处理靶标菌,将导致菌体蛋白质、核酸等大分子物质的外流;处理菌株葡聚糖结     

Arbuscular mycorrhizal fungus enhances P acquisition of wheat (Triticum aestivum L.) in a sandy loam soil with long-term inorganic fertilization regime

The P efficiency, crop yield, and response of wheat to arbuscular mycorrhizal fungus (AMF) Glomus caledonium were tested in an experimental field with long-term (19 years) fertilizer management. The experiment included five fertilizer treatments: organic amendment (OA), half organic amendment plus half mineral fertilizer (1/2 OM), mineral fertilizer NPK, mineral fertilizer NK, and the control (without fertilization). AMF inoculation responsiveness (MIR) of wheat plants at acquiring P were estimated by comparing plants grown in unsterilized soil inoculated with G. caledonium and in untreated soil containing indigenous AMF. Without AMF inoculation, higher crop yields but lower colonization rates were observed in the NPK and two OA-inputted treatments, and NPK had significantly (P < 0.05) lower impacts on organic C and available P in soils and thereby P acquisition of wheat plants compared with OA and 1/2 OM. G. caledonium inoculation significantly (P < 0.05) increased colonization rates with the NPK and two P-deficient treatments but significantly (P < 0.05) increased vegetative biomass, crop yield, and P acquisition of wheat as well as soil alkaline phosphatase (ALP) activity, only with the NPK treatment. This gave an MIR of ca. 45% on total P acquisition of wheat plants. There were no other remarkable MIRs. It suggested that the MIR is determined by soil available P status, and rational combination of AMF with chemical NPK fertilizer can compensate for organic amendments by improving P-acquisition efficiency in arable soils.