鲤和团头鲂幼鱼卵黄蛋白原的诱导、纯化及电泳比较

采用腹腔注射人工雌激素 1 7α 乙炔基雌二醇 (1 7α ethinyloestradiol,EE2 )的方法 ,在鲤幼鱼和团头鲂幼鱼体内诱导生成卵黄蛋白原 ;并结合利用阴离子交换介质DEAE SephraroseCL 6B和液相层析技术分离纯化了诱导后的鲤幼鱼和团头鲂幼鱼血浆中的卵黄蛋白原 ;SDS PAGE电泳结果表明所分离的两种鲤科鱼类卵黄蛋白原其亚基的分子量分别为 1 70KD和1 5 0KD。

The price of pain and the value of suffering.

Estimating the financial value of pain informs issues as diverse as the market price of analgesics, the cost-effectiveness of clinical treatments, compensation for injury, and the response to public hazards. Such valuations are assumed to reflect a stable trade-off between relief of discomfort and money. Here, using an auction-based health-market experiment, we show that the price people pay for relief of pain is strongly determined by the local context of the market, that is, by recent intensities of pain or immediately disposable income (but not overall wealth). The absence of a stable valuation metric suggests that the dynamic behavior of health markets is not predictable from the static behavior of individuals. We conclude that the results follow the dynamics of habit-formation models of economic theory, and thus, this study provides the first scientific basis for this type of preference modeling.

When fear is near: threat imminence elicits prefrontal-periaqueductal gray shifts in humans.

Humans, like other animals, alter their behavior depending on whether a threat is close or distant. We investigated spatial imminence of threat by developing an active avoidance paradigm in which volunteers were pursued through a maze by a virtual predator endowed with an ability to chase, capture, and inflict pain. Using functional magnetic resonance imaging, we found that as the virtual predator grew closer, brain activity shifted from the ventromedial prefrontal cortex to the periaqueductal gray. This shift showed maximal expression when a high degree of pain was anticipated. Moreover, imminence-driven periaqueductal gray activity correlated with increased subjective degree of dread and decreased confidence of escape. Our findings cast light on the neural dynamics of threat anticipation and have implications for the neurobiology of human anxiety-related disorders.

HLA-DQB1*0301与胃腺癌及幽门螺杆菌感染的关系

为探讨HLA DQB1等位基因与胃腺癌临床特征及其幽门螺杆菌 (Hp)感染的关联性 ,运用序列特异性引物聚合酶链反应技术 ,检测无亲缘关系湖北汉族健康人 136例、胃癌组 6 3例患者的HLA DQB1基因。内镜活检、Giemsa染色和 (或 )外周血ELISA检查胃粘膜Hp感染情况。SAS软件统计处理。结果表明HLA DQB1 0 30 1与湖北汉族人胃腺癌呈正关联。携带与非携带该等位基因患者 ,其临床特征包括患者平均患病年龄、性别比、肿瘤原发部位、肿瘤TNM分期、肿瘤细胞分化程度 ,以及Hp感染率等情

长江洞庭湖口原生动物的生态学研究

对长江洞庭湖口原生动物群落为期三年的研究结果：种类组成、季节分布、优势种类、丰度的季节变化等，同时还依据食性分析了各种类的功能营养类群，并对河流中原生动物的来源、长江中上游地区原生动物种类组成规律、原生动物功能营养类群和优势种类在河流污染监测中的指示作用等进行了讨论。

对-氯代苯胺(PCA)在填充床生物反应器中的降解作用

以氯代苯胺（ＰＣＡ）为选择基质，用驯化技术从降解对二氯苯（ｐＤＣＢ）的富集培养物中得到了以同化ＰＣＡ为唯一碳源和氮源的混合微生物．将这种固定在填充床反应器中的微生物用于ＰＣＡ的降解作用研究中．在该反应器里，ＰＣＡ的生物降解遵循Ｌｏｇｉｓｔｉｃ方程ｑ＝ｑｍａｘ／（１＋ｅα－βＵｖ）．由方程求出了主要的动力学常数，Ｋｓ（半速率常数）和ｑｍａｘ（最大比基质降解速率）．于ＰＣＡ降解的同时，释放氯离子到培养基中．在水力停留时间３ｈ，进水ＰＣＡ浓度为３６０ｍｇ·Ｌ－１情况下，基质的体积降解率达到１２５ｍｇ·Ｌ－１

中国新记录──小金色藻在武汉东湖的季节消长

一种未曾在中国报道过的小金色藻（ＣｈｒｙｓｏｃｈｒｏｍｕｌｉｎａｐａｒｖａＬａｃｋｅｙ）在武汉东湖发现，此种在冬季出现，春末消失，高的种群密度（８３５７．６ｃｅｌｌｓ／ｍｌ及８７３７．０ｃｅｌｌｓ／ｍｌ）分别在１９９１年２月及１９９２年１月在水温为６─８℃时形成，持续时间近１个月，小金色藻的生物量在东湖营养状况不同的三个采集站是不同的，但季节消长的趋势基本上一致。此种喜生长在富营养的水体中。

大肠埃希氏菌引起的虹鳟鱼病的初步研究

1988年,山西省虹鳟鱼试验场的二龄虹鳟发生一种流行病,病鱼典型症状为:体色发黑,鳃丝苍白或粉红,肛门及有的鳍条充血,内脏肠、肝、脾等充血和出血。病原菌为革兰氏阴性,杆状,0.9—1.2×2.3—4.5μm,周鞭毛、能运动,周身还有菌毛(Pili)。能还原硝酸盐为亚硝酸盐;氧化酶阴性;葡萄糖发酵并产气,甲基红和靛基质试验阳性,V-P试验阴性;不产生尿素酶,苯丙氨酸脱氨酶和硫化氢:不利用丙二酸钠;不液化明胶;在KCN培养基和枸橼酸盐琼脂上不生长;发酵蔗糖、麦芽糖、甘露醇、水杨苷、山梨醇、阿拉伯糖、棉子糖;不

塘堰种稗养鱼的效果及其原理的初步分析

本文总结了稗草栽培的技术要点和鱼种合理放养的经验,测定了种稗塘堰底土和水中的氮、磷含量的变化,观察了稗草在分解过程中氮、磷营养物质的释放情况及其对浮游生物增殖的影响,进而对种稗养鱼的基本原理作了初步的分析。

Efficiency of constructed wetlands in decontamination of water polluted by heavy metals

A twin-shaped constructed wetland (CW) comprising a vertical flow (inflow) chamber with Cyperus alternifolius followed by a reverse-vertical flow (outflow) chamber with Villarsia exaltata was assessed for decontamination of artificial wastewater polluted by heavy metals. After application of Cd, Cu, Pb, Zn over 150 days, together with Al and Mn during the final 114 days, no heavy metals with the exception of Mn could be detected in either the drainage zone at the bottom, shared by both chambers, or in the effluent. The inflow chamber was, therefore, seen to be predominantly responsible for the decontamination process of more toxic metal species with final concentrations far below WHO drinking-water standards. About one-third of the applied Cu and Mn was absorbed, predominantly by lateral roots of C. alternifolius. Lower accumulation levels were observed for Zn (5%), Cd (6%), Al (13%). and Pb (14%). Contents of Cd, Cu, Mn, and Zn in soil were highest in top layer, while Al and Pb were evenly distributed through the whole soil column. Metal species accumulating mainly in the top layer can be removed mechanically. A vertical flow CW with C. alternifolius is an effective tool in phytoremediation for treatment of water polluted with heavy metals. (C) 2002 Elsevier Science B.V. All rights reserved.

Genome segment S8 of grass carp hemorrhage virus encodes a virion protein

The complete nucleotide sequence of the genome segment S8 of grass carp hemorrhage virus (GCHV) was determined from cDNA corresponding to the viral genomic RNA. It is 1,287 nucleotides in length and contains a large open reading frame that could encode a protein of 409 amino acids with a predicted molecular mass of 44 kD. The S8 was expressed using the pET fusion protein vector and detected by Western blotting analysis using the chicken egg IgY against intact GCHV particles, indicating that S8 encodes a virion protein. Amino acid sequence comparisons revealed that the protein encoded by S8 is closely related to protein alpha2 of mammalian reovirus, suggesting that the deduced protein of S8 is an inner capsid protein. Copyright (C) 2001 S. Karger AG, Basel.

Study on the thermal stability of InN by in-situ laser reflectance system

The thermal stability of InN in the growth environment in metalorganic chemical vapor deposition was systematically investigated in situ by laser reflectance system and ex situ by morphology characterization, X-ray diffraction and X-ray photoelectron spectroscopy. It was found that InN can withstand isothermal annealing at temperature as high as 600 degrees C in NH3 ambient. While in N-2 atmosphere, it will decompose quickly to form In-droplets at least at the temperature around 500 degrees C, and the activation energy of InN decomposition was estimated to be 2.1 +/- 0.1 eV. Thermal stability of InN when annealing in NH3 ambient during temperature altering would be very sensitive to ramping rate and NH3 flow rate, and InN would sustain annealing process at small ramping rate and sufficient supply of reactive nitrogen radicals. Whereas In-droplets formation was found to be the most frequently encountered phenomenon concerning InN decomposition, annealing window for conditions free of In-droplets was worked out and possible reasons related are discussed. In addition, InN will decompose in a uniform way in the annealing window, and the decomposition rate was found to be in the range of 50 and 100 nm/h. Hall measurement shows that annealing treatment in such window will improve the electrical properties of InN. (c) 2005 Elsevier B.V. All rights reserved.