四种底栖螺类饥饿代谢的研究

研究了四种常见优势底栖螺类的饥饿代谢(R,mgO2/ind.d)与温度(T,℃)、体重(Wd,mg dry-wt或Ww,mg wet-wt)的关系,并计算出三者间的复合关系,分别是:铜锈环棱螺,R=0.044Wd0.537e0.061T;长角涵螺,R=0.0004Ww0.9405·e0.0735T;纹沼螺,R=0.004Wd1.072e0.091T;短沟蜷,R=0.023Wd0.777e0.042T。       

饥饿和再投喂对鲇血液生理生化指标的影响

在室内可控条件下,对鲇（Silurus asotusLinnaeus）进行7d、14d和21d的饥饿处理,随后各组恢复投喂20d,研究饥饿和再投喂对鲇血液生理生化指标的影响。结果显示：饥饿过程中,鲇血液红细胞数和血红蛋白14d内上升,血红蛋白上升显著（p〈0.05）,21d后两项生理指标开始下降;饥饿7d后血糖浓度显著下降（p〈0.05）,饥饿14d和21d后趋于相对稳定;总蛋白、白蛋白和球蛋白均呈下降趋势,分别在饥饿的14d、7d和21d后与饥饿前达到显著性差异（p〈0.05）;甘油三酯和总胆固醇分别在饥饿7d和21d后显著下降（p〈0.05）;饥饿14d后Na＋和Cl-浓度显著下降（p〈0.05）,21d后Na＋浓度却又显著上升（p〈0.05）,Cl-浓度有所回升;Ca2＋浓度在饥饿过程中逐渐下降,且差异显著（p〈0.05）。饥饿对K＋浓度和碱性磷酸酶活力没有明显影响。恢复投喂20d后,测定的血液指标均有不同程度的恢复。采用二元三次方程（CUB类型）就各项生理生化指标对饥饿时间（d）进行的回归分析表明,Ca2＋与饥饿时间的决定系数（R2）最大,为0.964,因此将鲇血液的Ca2＋浓度作为其饥饿的评价指标则相对可信。     

EFFECTS OF GLUCOSE ON THE PROCESS OF CHLOROPLAST DEVELOPMENT IN CHLORELLA PROTOTHECOIDES

By growing Chlorella protothecoides in a medium rich in glucoseand poor in nitrogen source (urea), the entirely chlorophyll-lesscells showing no discernible plastid structure and containingonly little RNA and protein were obtained. These cells, whichwere called "glucosebleached" cells, turned green after a certainlag period, when they were incubated, in the light, in a mediumcontaining the nitrogen source and basal mineral nutrients butwithout glucose. As has been shown in previous studies, thisgreening process involves two consecutive steps : a light-independentphase, in which RNA plays an essential role, and a light-requiringphase, in which the chlorophyll formation and full organizationof chloroplast take place accompanied by the formation of acertain species of protein ("alkali-stable" protein). The wholeprocess of greening was found to be profoundly suppressed byaddition of glucose, the degree of suppression being determinedby the relative concentrations of glucose and the nitrogen source.The primary act of glucose was manifest in the repression ofsyntheses of RNA, and of the species of protein mentioned above,which participate in, or causally related to, the first andsecond phases, respectively, in the greening process. ¹ This paper was read at the Symposium on Extranuclear Self-reproducingSystems held by the Botanical Society of Japan in October, 1964     

萘及其衍生物对普通小球藻的毒性效应

本文研究了萘及其衍生物(萘、1-萘酚、2-萘酚和1-萘胺)对普通小球藻的生长、叶绿素含量、光合强度和呼吸强度的影响。萘、1-萘酚和1-萘胺在低浓度下能促进普通小球藻的生长,高浓度则抑制藻的生长;2-萘酚在实验浓度下都抑制藻的生长。萘、1-萘酚、2-萘酚和1-萘胺的96hEC_(50)分别为98.06、11.87、13.39和6.95mg/L。萘及其衍生物对叶绿素含量和光合强度的影响比对生长的影响强,而对叶绿素含量的影响又比对光合强度的影响强。可以这样认为:萘及其衍生物对普通小球藻生长的抑制是通过抑制藻叶绿素a的形成,进而降低光合强度实现的。低浓度的萘和1-萘酚增强普通小球藻的呼吸强度,而高浓度则减弱;与此相反,低浓度的2-萘酚对藻的呼吸强度影响不大,高浓度能显著增强;在实验浓度下的1-萘胺使藻呼吸强度明显减弱,但随着时间的推移,呼吸强度出现回升,且高浓度回升较快。     

冷驯化对中缅树鼩能量代谢的影响

在5 ±1 ℃条件下对中缅树鼠句进行冷驯化处理, 测定其能量代谢。冷驯化28 d 后, 体重比对照组显著增加7.33 %; 整体能值达到30.47 ±0.46 kJ / g (N = 8) , 比对照组增加4.98 %; 摄入能比对照组增加36.17 %; 同化能比对照组增加66.2 %; 生长能达到6.98 ±0.53 kJ / 100 g (N = 7) 体重·天, 是对照组的4.85 倍; 维持能比对照组增加64.0 % , 达到352.96 ±28.34 kJ / 100 g 体重·天(N = 7) 。以上结果表明中缅树鼠句在冷胁迫影响下, 以增加能量摄入、能量储存和维持能和降低排泄能量的生理机制来维持能量代谢平衡, 以此对策来提高低温环境适应能力。
     

冷驯化对中缅树能量代谢的影响

在 5± 1℃条件下对中缅树鼠句进行冷驯化处理 ,测定其能量代谢。冷驯化 2 8d后 ,体重比对照组显著增加 7 3 3 % ;整体能值达到 3 0 47± 0 46kJ/g (N =8) ,比对照组增加4 98% ;摄入能比对照组增加 3 6 1 7% ;同化能比对照组增加 6 6 2 % ;生长能达到 6 98±0 5 3kJ/1 0 0g (N =7)体重·天 ,是对照组的 4 85倍 ;维持能比对照组增加 6 4 0 % ,达到3 5 2 96± 2 8 3 4kJ/1 0 0g体重·天 (N =7)。以上结果表明中缅树鼠句在冷胁迫影响下 ,以增加能量摄入、能量储存和维持能和降低排泄能量的生理机制来维持能量代谢平衡 ,以此对策来提高低温环境适应能力     

TEMPERATURE CHARACTERISTICS FOR THE METABOLISM OF CHLORELLA : III. THE CATALYTIC DECOMPOSITION OF HYDROGEN PEROXIDE BY CHLORELLA PYRENOIDOSA

The decomposition of hydrogen peroxide by intact Chlorella cells follows a first order course at very low temperatures, but at higher temperatures gives falling first order constants. Between 0.6° and 20°C. the value of µ is 10,500 calories.     

EFFECTS OF ELECTRICAL STIMULATION OF THE NIGROSTRIATAL PATHWAY OF THE RAT ON DOPAMINE METABOLISM

Abstract— Electrical stimulation of the nigrostriatal dopaminergic pathway in rat brain elicited a frequency and current intensity-dependent increased in the formation of homovanillic acid in the basal ganglia. The accumulation of the acid in probenecid-treated animals was constant over 1 h, when maximally stimulated at 25 Hz and 300 μA. Dopamine levels remained unchanged during stimulation. When prior to stimulation the inhibitor of catecholamine synthesis α-methyl- p -tyrosine methyl ester was administered, dopamine levels declined biphasically. Tyrosine and nomifensine, a dopamine uptake inhibitor, and apomorphine had no major effect on the formation of homovanillic acid, whilst α-methyl- p -tyrosine prevented its formation. Our data suggest that dopamine in the striatum is compartmentalized and that the newly-synthesized amine is released and converted to homovanillic acid. Apomorphine decreases dopamine flux only when dopaminergic neurons are at rest. When depolarized neither access of the precursor nor reuptake seem to influence the conversion of dopamine to homovanillic acid.     

饥饿对杂交鲟仔鱼摄食、生长和体成分的影响

仔鱼期是鱼类生活史中最脆弱,对环境条件最敏感的时期,饥饿是导致此阶段仔鱼死亡的主要原因之一,也是海洋鱼类补充量研究的焦点之一。殷名称曾指出采用饥饿研究的方法,可以确定仔鱼的初次摄食期和不可逆点(Point of no return),这对于鱼类苗种培育和人工养殖具有十分重要的意义。最近,王吉桥等、宋昭彬等开始将饥饿研究应用于多种淡水鱼类仔鱼。然而,有关鲟类仔鱼的饥饿研究至今未见报道。       

SOME EFFECTS OF DERIVATIVES OF VITAMIN K ON THE METABOLISM OF UNICELLULAR ALGAE

Vitamin K₁, 2-methyl-3-phytyl-1,4-naphthoquinone, is a substance found in all plant chloroplasts. It is, therefore, interesting to know whether it has any influence upon the metabolism of plants. Experiments made with the phytol-free derivatives like 2-methyl-1,4-naphthoquinone or the corresponding 3-oxy compound, phthiocol, gave the following results. These substances accelerate the respiration of Chlorella or Scenedesmus in a way similar to the action of the dinitrophenols. They inhibit photosynthesis and the compensation of respiration in the light strongly like hydroxylamine. In Scenedesmus they hinder the adaptation to the anaerobic utilization of hydrogen. If given after adaptation in amounts sufficient to stop photosynthesis they do not prevent photoreduction but rather stabilize this reaction against reversion. Their presence destroys the coupling between the reduction of carbon dioxide in the dark and the oxyhydrogen reaction in adapted algae. One can expect, therefore, that the natural vitamin K present in plants in concentrations of about 10^–3 M takes part in some metabolic reaction as a catalyst or regulator.