Intrinsic properties and extrinsic neurohormonal control of crab cardiac hemodynamics

This report provides the first direct measurements of the stroke volume and total cardiac output of crustacean hearts, as recorded from a semi-isolated in vitro preparation. The responses to mechanical perturbations, changes in preload and afterload, show that these hearts do not possess automatic compensatory Frank-Starling-like mechanisms. Heart rate, reflecting the burst rate of the cardiac ganglion, is minimally affected by stretch. On the other hand, these hearts are exquisitely responsive to the neurohormones of the pericardial organs. Serotonin, CCAP and proctolin all produce positive chronotropic and inotropic effects, but the responses to each are unique. Two FMRFamide peptides were positively chronotropic, but negatively inotropic.     

采用ICP-AES法测定香烟烟气成分中金属离子在动物体内的蓄积

通过动物被动吸烟模型,考察大白兔在被动吸烟后不同时期肾脏组织样本中7种重金属(Hg,Se,Sn,Pb,Pd,Ni和Cr)含量的变化,用微波酸湿消化法处理试样制备测试液,用电感耦合等离子体原子发射光谱法(ICP-AES法)同时测定Hg,Se,Sn,Pb,Pd,Ni和Cr这7种元素的含量.研究结果表明:采用ICP-AES法,加标回收率达95.0％～104.2％,相对标准偏差为1.3％～4.1％,具有良好的准确度和精密度;大白兔在被动吸食香烟后肾脏中Hg,Se,Pb,Cd和Cr这5种金属离子含量显著提高,并以吸食NISE组香烟金属离子含量提高最大,经12周后,以上几种元素在肾脏中含量较正常组分别高5.6,8.1,12.9,4.7和3.8倍.     

B6-Trp53tm1 /NIFDC 小鼠在MNU 给药后的体质量、脏器质量、血液学及血生化指标的测定

摘要: 目的测定自主建立的p53 + / － 基因敲除小鼠( B6-Trp53tm1 /NIFDC) 在N-甲基-N-亚硝基脲( N-Methyl-Nnitrosourea,MNU) 给药后体质量、脏器质量、血液学及血生化指标,为临床前药物安全评价致癌性实验短期体内替代试验候选遗传修饰动物模型提供背景性数据。方法共设计4 个组: 阴性对照组( 野生型小鼠) 给予生理盐水、溶媒对照组( B6-Trp53tm1 /NIFDC 小鼠) 给予枸橼酸缓冲液、MNU 组1 ( B6-Trp53tm1 /NIFDC 小鼠) 给予75 mg /kg MNU、MNU 组2( 野生型小鼠) 给予75 mg /kg MNU,阴性对照组和MNU 组2 每组野生型小鼠各20 只,雌雄各半,溶媒对照组和MNU 组1 每组B6-Trp53tm1 /NIFDC 小鼠各20 只,雌雄各半,测定其体质量、主要脏器质量、相对脏器质量、血液学及血生化指标,并进行统计分析。结果MNU 组1、MNU 组2 动物体质量降低与阴性对照组、溶媒对照 组相比都存在显著性统计学差异( P ＜ 0. 05) 。MNU 组1、MNU 组2 动物心脏、肝脏、脾脏、肺脏、胸腺和颌下腺的绝对质量与阴性对照组、溶媒对照组相比有显著性统计学差异( P ＜ 0. 05) 。MNU 组1 和MNU 组2 动物心脏、肝脏、脾脏、肺脏、肾脏、脑、胸腺和颌下腺的相对质量与阴性对照组、溶媒对照组相比有显著性统计学差异( P ＜ 0. 05) 。MNU 组1 和MNU 组2 动物均发现NEU、LYM%、LUC%、ＲBC、HGB、HCT、MCV、MCHC、ＲDW、HDW、CHCM、CHDW、PDW、MPV 及PLT 等15 个指标与阴性对照组和溶媒对照组相比有显著性统计学差异( P ＜ 0. 05) 。另外,MNU 组1 和MNU 组2 均发现TP、ALB、CＲEA、UＲEA、TCHO、TG、CA 等7 个指标与阴性对照组和溶媒对照组有显著性统计学差异( P ＜ 0. 05) ,MNU 组2 的AST 与阴性对照组和溶媒对照组有显著性升高( P ＜ 0. 05) ,但MNU 组1 和MNU 组2 组间没有显著性统计学差异。结论本文测定并分析了自主建立的p53 + / － 基因敲除小鼠( B6-Trp53tm1 /NIFDC) 和野生型小鼠分别给予MNU 及枸橼酸缓冲液后的体质量、脏器质量、血液学及血生化指标,该模型有望将来用于临床前药物安全评价致癌性实验短期体内替代试验。     

The role of perireceptor events in vertebrate olfaction

The perception of odours and pheromones is mediated by small soluble carrier proteins that belong to the family of lipocalins. Those secreted by the nasal mucosa are called odorant-binding proteins (OBPs) for their binding activity towards volatile compounds. Proteins of similar structure, which we call pheromone-binding proteins (PBPs), help to deliver volatile pheromones in the environment. They are present in high concentration in biological fluids, such as urine, saliva and vaginal discharge, involved in chemical communication between conspecifics. Several subclasses of OBPs have been identified in the same animal species, each best related to a particular group of PBPs. Such similarities, together with anatomical and behavioural evidence, suggest that OBPs may be involved in the perception of pheromones.     

快速成形技术在人工骨骼制造中的应用

快速成形(Rapid Prototyping,RP)技术可以迅速地将显示于计算机屏幕上的设计转化为可以进一步评估的实物.基于快速成形技术的制造方法融合了制造技术、生物技术、材料技术、信息技术,是一种高级制造形式.可以制造任意形状和结构生物器官,并使之具有生物活性.在人工骨骼制造中,多种快速成形工艺得到了应用与实践.     

竹类的营养器官及与生殖器官的内部结构之间相关性的初步研究

本文记载了33种竹类,在这33种竹种中,地下茎有合轴型、复轴型和单轴型三种;地上竿有竿生叶和营养叶。其生殖器官有假花序和真花序。从这些竹种的营养器官的内部结构和生殖器官的真、假花序中探索其演化关系。     

喀什哈尔葡萄花器及受精过程观察

本文对喀什哈尔葡萄花器的构造和开花特点作了详细介绍、剖析,这是对传粉受精的高度适应。受精过程如下:1、授粉后40—50分钟花粉粒萌发。2、授粉后6小时花粉管到达胚囊。3、授粉后8—10小时二个精子分别达卵细胞和次生核。4、授粉后24小时精、卵完成融合,受精作用属有丝分裂前型。5、授粉后20小时精子和次生核完成融合。了解此程为开花受精期的管理提供依据。     

Regression of genetically determined polycystic kidney disease in murine organ culture

Summary Cystic kidneys from the mutant CPK strain of C57BL/6J mice were cultured in serum-free organ culture. During 120 h of incubation in chemically-defined medium, CPK cystic tubular changes underwent complete regression. Environmental factors regulate the expression of genetically determined polycystic kidney disease in this model.