LIGHT AND THE SEXUAL CYCLE OF GAME BIRDS

The results of these experiments has led us to conclude that light is a primary factor in inducing sexual activity in pheasants, quail and grouse, through the mediation of the hypophysis. Once this hypophysealgonad reaction is started it can not continue indefinitely with adequate light but only until the hypophysis falters in the production of the gonad-stimulating hormone through causes unknown. The immature pheasant resembles the adult at the close of the breeding season in that the gonads are capable of responding to adequate hypophyseal stimulation.     

氮硫养分平衡对大白菜营养品质和抗病性影响的研究

研究了十字花科作物白菜施用硫肥对合硫必需氨基酸蛋氨酸和脱氨酸含量、硝酸根含量以及抗病性方面的影响。合理施用硫肥可以提高白菜体内胱氨酸和蛋氨酸的含量,同时降低有害物质ＮＯ３在组织内的积累,从而提高白菜的营养品质。适量施用硫肥减少氮肥用量可以大大改善白菜对霜霉病的抗病效果;;在低氮水平时还可以对病毒病和软腐病有一定的防治作用,但在高供氮水平时施用硫肥的抗病效果不明显。     

一种微生态制剂中抑菌物质的分离与鉴定

植物乳杆菌发酵产生的抑菌物质经乙醇浸提、SephadexG-15层析、氨基酸组成分析、反相液相色谱分离及鉴定，发现该植物乳杆菌产生的抑菌物质为一类分子量较小（小于1000Da)，且比较接近，极性不同的多肽。     

一种微生态制剂中抑菌物质的分离与鉴定

植物乳杆菌发酵产生的抑菌物质经乙醇浸提、SephadexG-15层析、氨基酸组成分析、反相液相色谱分离及鉴定，发现该植物乳杆菌产生的抑菌物质为一类分子量较小（小于1000Da)，且比较接近，极性不同的多肽。     

茄交链孢培养滤液中抗菌活性物质产生条件的研究

研究了不同培养条件对 Alternaria solani培养滤液抗菌活性的影响。结果表明，在 25℃黑暗静止条件下， pH值为 6.0的改良 Czapek 1培养液最有利于抗菌活性物质的产生，最佳培养时间为 28天。     

Conformation of N6-methyladenine, a base involved in DNA modification: restriction processes

Crystal structures of N(6),N(9)-dimethyladenine and N(6)-methyladenine hydrochloride were determined from three-dimensional x-ray diffraction data. The bases assume a conformation in which the N(6)-methyl group blocks one of the hydrogen-bonding sites normally used by adenine to form Watson-Crick pairs with thymine in double-helical DNA. When in this conformation, N(6)-methyladenine residues might alter the secondary structure of DNA. thereby preventing the scission of modified DNA's by restriction enzymes.     

Modified bases characterized in intact DNA by mass-analyzed ion kinetic energy spectrometry

Pyrolysis of DNA into a chemical ionization source yields protonated bases and other base-containing ions. Kinetic energy spectra allow the characterization of the bases 5-methylcytosine and 1-methyladenine from underivatized salmon sperm DNA. Isomeric bases are distinguishable with this technique.     

近缘毛壳Chaetomium subaffine LB-1抑菌物质存在部位及提取方法

【目的】对近缘毛壳Chaetomium subaffine菌株LB-1产生抑菌物质的部位及提取方法进行研究,为开发生防菌株LB-1防治植物病害奠定基础。【方法】以番茄灰霉病菌Botrytis cinerea和玉米大斑病菌Exserohilum turcicum为指示菌,采用平板密封培养法检测菌株LB-1是否产生挥发性抑菌物质;采用菌体超声破碎和液态培养的方式检测菌株LB-1产生的非挥发性抑菌物质存在的部位;采用含毒培养基法和滤纸片法检测菌株LB-1培养液的硫酸铵沉淀、盐酸沉淀和有机溶剂萃取物的抑菌效果,以确定菌株LB-1培养液中抑菌物质的提取方法。【结果】菌株LB-1与2种供试病原菌密封共培养时,对病原菌的生长没有明显影响,表明菌株LB-1不能产生挥发性抑菌物质。菌株LB-1菌体胞内提取物的抑菌活性与对照无差异,但其培养液对B. cinerea和E. turcicum的生长有较强的抑制作用,表明菌株LB-1产生的抑菌物质存在于菌体细胞外。菌株LB-1培养液的硫酸铵沉淀和盐酸沉淀对2种供试植物病原真菌的生长均无抑制效果,但有机溶剂萃取可获得菌株LB-1培养液中的抑菌物质,其中正丁醇萃取物...     

三角鲤几种常见天然饵料的营养分析与评价

研究从饵料营养分析入手,采用化学和生物学相结合方法,综合评价了三角鲤几种常见天然饵料的营养价值,结果表明:水蚤、水蚯蚓、野杂鱼均是三角鲤优质的饲料蛋白源及良好的能源物质;三种饵料的第一限制氨基酸同为蛋氨酸,第二限制氨基酸同为赖氨酸;三角鲤苗种培育效果比较,水蚤组显著优于水蚯蚓和野杂鱼组,而后两组间无明显差异。     

黄芪组织培养产生次生代谢产物──多糖过程的研究

在黄芪组织培养产生多糖的过程中,添加不饱和酯肪酸可使酯酶同功酶谱带发生改变,同时可提高多糖含量。由此证明多糖合成的前体物质为脂肪酸。     

雏鸡饲粮蛋氨酸水平对硒生物效能的影响

用1日令—4周令白洛克雏鸡,1日令—6周令京Ⅲ系雏鸡,以玉米、黄豆、小麦等组成的饲粮,加或不加硒(Se,Na_2SeO_3)和(或)蛋氨酸(DL—Wet),测定了饲粮不同蛋氨酸水平对硒生物效能的影响。以体增重,料肉比,全血和血浆谷胱甘肽过氧化物酶(GSHPx)活力,组织硒含量等指标为判据,试验结果表明,在0.1,0.2ppm硒水平,雏鸡饲粮蛋氨酸水平影响亚硒酸钠硒的生物效能,对饲料硒的生物效能也有所影响。在本试验饲粮条件下,补加蛋氨酸提高硒的生物效能,而以硒0.2ppm和蛋氨酸0.5％的用量(饲料自身含量+添加量)为适宜配比。     

施氮量对驻马店不同烤烟品种化学成分和香气物质的影响

在河南驻马店研究了不同施氮量对3个烤烟品种叶片化学成分和香气物质含量的影响。结果表明:施氮量和品种均对各部位烟叶的化学成分和香气物质含量产生了不同程度的影响。施氮量对优选一号化学成分含量的影响最小,对NC89的影响最大。优选一号在高氮肥水平下、NC89在中高氮肥水平下均能得到化学成分协调、致香物质丰富的烟叶。主栽品种云烟87在3个氮肥水平(30～90 kg/hm2)下均能得到质量较好的烟叶。     

Constitutive expression of feedback-insensitive cystathionine γ-synthase increases methionine levels in soybean leaves and seeds

Soybean(Glycine max(L.) Merr.) is a major crop that provides plant-origin protein and oil for humans and livestock.Although the soybean vegetative tissues and seeds provide a major source of high-quality protein,they suffer from low concentration of an essential sulfur-containing amino acid,methionine,which significantly limits their nutritional quality.The level of methionine is mainly controlled by the first unique enzyme of methionine synthesis,cystathione γ-synthase(CGS).Aiming to elevate methionine level in vegetative tissues and seeds,we constitutively over-expressed a feedback-insensitive Arabidopsis CGS(At D-CGS) in soybean cultivars,Zigongdongdou(ZD) and Jilinxiaoli 1(JX).The levels of soluble methionine increased remarkably in leaves of transgenic soybeans compared to wild-type plants(6.6-and 7.3-fold in two transgenic ZD lines,and 3.7-fold in one transgenic JX line).Furthermore,the total methionine contents were significantly increased in seeds of the transgenic ZD lines(1.5-to 4.8-fold increase) and the transgenic JX lines(1.3-to 2.3-fold increase) than in the wild type.The protein contents of the transgenic soybean seeds were significantly elevated compared to the wild type,suggesting that the scarcity of methionine in soybeans may limit protein accumulation in soybean seeds.The increased protein content did not alter the profile of major storage proteins in the seeds.Generally,this study provides a promising strategy to increase the levels of methionine and protein in soybean through the breeding programs.     

微生物驱油提高原油采收率技术的室内研究

微生物驱油是一种通过引入在油藏中能存活的微生物来提高原油采收率的技术 ,相对于微生物单井吞吐而言 ,具有作用范围广 ,作用周期长的优点。通过试验引入微生物 ,选择特定的激活培养基 ,达到提高采收率的目的。     

Postnatal sex reversal of the ovaries in mice lacking estrogen receptors alpha and beta

Mice lacking estrogen receptors alpha and beta were generated to clarify the roles of each receptor in the physiology of estrogen target tissues. Both sexes of alphabeta estrogen receptor knockout (alphabetaERKO) mutants exhibit normal reproductive tract development but are infertile. Ovaries of adult alphabetaERKO females exhibit follicle transdifferentiation to structures resembling seminiferous tubules of the testis, including Sertoli-like cells and expression of Müllerian inhibiting substance, sulfated glycoprotein-2, and Sox9. Therefore, loss of both receptors leads to an ovarian phenotype that is distinct from that of the individual ERKO mutants, which indicates that both receptors are required for the maintenance of germ and somatic cells in the postnatal ovary.     

铜源和铜水平对岢岚绒山羊生长发育和产绒性能的影响

为研究不同铜源和不同剂量铜对绒山羊生长发育、绒产量和绒品质的影响,选用体重相近的岢岚绒山羊6月龄青年母羊40只,随机分为5组,分别饲喂添加铜水平为0 mg.kg-1(对照组)、25 mg.kg-1和100 mg.kg-1DM硫酸铜2、5 mg.kg-1和100 mg.kg-1DM蛋氨酸铜的日粮,进行为期70 d的试验,其中预试期10 d。结果表明:日粮添加铜显著提高了岢岚绒山羊青年母羊的体重(P0.05),但其绒自然长度和绒细度不受铜添加水平的影响(P0.05)。添加25 mg.kg-1DM硫酸铜或蛋氨酸铜组显著提高了周岁母羊产绒量和绒的伸直长度。因此,在绒山羊青年母羊的日粮中,硫酸铜或蛋氨酸铜添加量以25 mg.kg-1DM为宜。     

高碘日粮对试验蛋鸡器官组织学影响的研究之一──对蛋鸡卵巢未成熟卵泡闭锁率影响的组织学观察

在基础日粮（含碘０．２００８ｍｇ／ｋｇ）中添加１２５０ｍｇ／ｋｇ碘,对Ｈｉｓｅｘ蛋鸡连续饲喂５周,使其卵巢皮质内初级卵泡的闭锁率较对照组升高差异极显著（Ｐ＜０．０１）,次级卵泡的闭锁率上升差异显著（Ｐ＜０．０５）,单位面积卵泡的最大密度下降差异极显著（Ｐ＜０．０１）,卵巢基质内印黄颗粒的最大密度上升差异极显著（Ｐ＜０．０１）,卵巢间质细胞最大密度升高差异显著（Ｐ＜０．０１）．试验提示,高碘引起鸡产蛋量下降的主要形态学基础是各级卵泡的闭锁．     

Metkephamid, a systemically active analog of methionine enkephalin with potent opioid alpha-receptor activity

Metkephamid is an analog of methionine enkephalin that retains high affinity for the delta receptor and is a systemically active analgesic. Since it is at least 100 times more potent than morphine as an analgesic when placed directly into the lateral ventricles, and is 30 to 100 times more potent on the delta receptor and yet is roughly equipotent on the mu receptor in vitro, it is concluded that it probably produces analgesia by action on delta receptors as well as, or rather than, on mu receptors. It has less tendency to produce respiratory depression, tolerance, and physical dependence than standard analgesics, and it is presently undergoing clinical trial.     

抗苗勒氏管激素与多囊卵巢综合征卵泡发育相关性的研究进展

卵泡发育异常是多囊卵巢综合征（PCOS）的核心病理生理机制之一。卵泡发育的卵巢局部调控作用日益突显。抗苗勒氏管激素（AMH）相当于卵泡发育负反馈调控机制,与女性卵巢功能密切相关,在PCOS患者中表达异常,可能是PCOS卵泡发育异常及性激素合成失调的重要影响因子,可早期预测PCOS,并作为诊断PCOS卵泡发育障碍程度的特异性指标及诊治的新靶点和突破点之一。因此,有必要进一步以卵巢局部AMH为靶点,深入研究其产生时间、细胞定位及分子机制等问题。     

生物工程应用于作物育种的试验研究 第1报 外源DNA导致水稻性状变异

文中报导了外源 DNA 处理水稻幼苗引起性状变异,获得了高赖氨酸、高蛋氨酸的85-02等4个变异株,并观察了变异株外观形态特征、产量性状,测定了幼苗的过氧化物酶活性、过氧化物酶同工酶、糙米的全氨基酸和蛋白质含量。