PHYCOLOGY IN THE FIELD AND IN THE LABORATORY1

Field and laboratory phycologists are still following different paths. This is regrettable because their labors supplement one another, and only by co-operation can progress be achieved.     

THE DEVELOPMENT OF THE DORSAL AND VENTRAL MAMMALIAN PANCREAS IN VIVO AND IN VITRO

The origin, morphogenesis, and biochemical differentiation of the dorsal and ventral pancreas of the rat embryo have been investigated in order to ascertain the similarities and dissimilarities between the two lobes. We have utilized a culture system in which the primitive gut gives rise to a number of differentiated organs, including the dorsal and ventral pancreas. The two pancreases do not undergo fusion in these cultures, thus allowing independent analyses of the two lobes for comparison with in vivo results. The dorsal pancreas first appeared at the 23–25 somite stage while the ventral pancreas appeared approximately 12 hr later at the 29–30 somite stage. Guts from embryos as young as 12 somites were capable of developing both pancreases in vitro. In spite of the 12 hr difference between the times of their appearance, the dorsal and ventral pancreases exhibited identical patterns of morphological and biochemical differentiation. The two lobes contained the same exocrine enzymes and hormones, at similar levels, differing only in their glucagon content, the dorsal pancreas possessing a fivefold higher glucagon specific activity. The implications of these results are discussed.     

VASCULAR SUPPLY AND STRUCTURE OF THE OVULE AND ARIL IN PEONY AND OF THE ARIL IN NUTMEG

Camp , Wendell H., and Mary M. Hubbard . (U. Connecticut, Storrs.) Vascular supply and structure of the ovule and aril in peony and of the aril in nutmeg. Amer. Jour. Bot. 50(2): 174–178. Illus. 1963.—Examination of the placental region in the carpel of Paeonia indicates a complexity and super-abundance of vascular supply beyond that usually found in angiosperms and certainly more than is necessary for adequate nutrition and water supply of the ovules. From this it is concluded that the ovules once were borne on a larger and more complex structure than the present carpel. Vascular strands leading to the aril and the hypostase are interpreted as being relictual. The large multifid aril of Myristica has a well-developed vascular system composed of several sizes of branched bundles.     

PURIFIED DIPHTHERIA ANTITOXIN IN THE ULTRACENTRIFUGE AND IN THE ELECTROPHORESIS APPARATUS

Ultracentrifugation studies of diphtheria antitoxin showed that: 1. Purified antitoxin of high activity obtained from horse plasma without enzymatic treatment has exactly the same sedimentation constant as the globulin fraction obtained in a similar way from normal horse plasma s ₂₀ ^water = 6.9 x 10^–13. 2. Purified antitoxin obtained with trypsin digestion of the toxin-antitoxin complex has a sedimentation constant of s ₂₀ ^water = 5.5 ± 0.1 x 10^–13, a diffusion constant of D ₂₀ ^water = 5.7₆ x 10^–7, and a molecular weight of about 90,000. Electrophoresis experiments demonstrated that: 1. The trypsin-purified antitoxin has an isoelectric point not far from pH 7.0. 2. The reversible spreading noticed at about pH 7.3 cannot be attributed to heterogeneous preparation. 3. The large increase in the γ-globulin fraction occurring during immunization consists either of antitoxin of various degrees of activity or of some inert protein in addition to the antitoxin.     

苏北麦田杂草与温度关系的初步观察及其防除问题

1979—1985年,对苏北地区麦田主要恶性杂草幼苗的生态习性进行了研究,猪殃殃,麦家公,野燕麦、大巢菜等种子的最适发芽温度分别为10℃、10—15℃、15℃、20℃;种子发芽起点温度分别为1.10±0.29、-0.46±1.29、0.06±3.09和3.54±2.42℃,均低于小麦的起点发芽温度(1—2℃)。种子发芽有效积温分别为87.04±2.54(℃)、133.70±16.53(℃)、84.24±15.87(℃)和58.66±10.91(℃),均高于小麦种子发芽的有效积温(50℃)。田间调查,猪殃殃等麦田杂草出苗,幼苗生长对温度及历期的要求与播种期关系极密切,一般比小麦迟出苗1—8天,但出土后的生长势很快超过小麦,且有播期不同而分批出土为害的习性。用苯达松防除猪殃殃;用野麦畏,苯达松防除麦家公;用野麦畏、禾草灵、野燕枯防除野燕麦;用苯氧乙酸类除草剂防除大巢菜等阔叶杂草,并将其消灭在苗期阶段,可取得显著的灭草增产效果。     

STUDIES IN THE GENETICS AND CYTOLOGY OF TWO SPECIES IN THE GENUS ASTER AND THEIR POLYMORPHY IN NATURE

The following genetical and cytological studies were made in conjunction with investigations in relative growth and morphogenesis (Delisle, 1938) in two species of Aster, A. novae-angliae L., A. multiflorus Ait.² and their hybrid. Certain aspects of this work appear significant when considered in relation to the polymorphy of these species and possibly have a bearing on the recognized polymorphy in the genus. A. novae-angliae is tall, hairy, stout, and relatively unbranched in the young stages, becoming corymbed only at the summit later. It has numerous large, soft, minutely pubescent, lanceolate, acute, entire leaves which are provided with marked auriculations at the base. The bracts of the involucre are loose, erect, nearly equal, glandular-viscid and linear; the heads are characteristically solitary on individual branchlets; the rays of the type species are violet-purple and those of the forms roseus (Desf.) Britton and geneseensis. House are rose and white, respectively. This species flowers from August to October, with the bulk of the plants blooming in September.     

PATHOLOGY AND THE PATHOLOGIST IN THE CANCER PROGRAM

Cancer as one of the most important human diseases does not present as formidable a problem as infectious disease did a century ago. The diversified cancer program, combining voluntary and governmental agencies in support of research, education and coordinated teamwork in the clinical care of the patient, presents a varied although unified approach to the problem that has never before been available for the study of any single human disease. Pathology, with its applied methods from the basic sciences, has a singular role in the scientific aspect of the cancer program. Representing a new specialty in medicine and embodying an inquiring approach to the study of human disease, pathology has a leading role to play. The pathologist, assuming the new role of “pathologist-physician” brings to the clinical care of the cancer patient the most precise methods of cancer diagnosis. The “pathologist-physician” should be a pivotal member of the “clinical team” in the immediate diagnosis, care and treatment of the cancer patient.     

鲤科鱼类前方椎体的形成及其在系统发育上的意义

本文对九种鲤科鱼类与中国胭脂鱼幼体的前方椎体的发育进行了比较。观察结果表明这两个科鱼类的前方椎体发育是近似的,它们的魏氏小骨有共同的来源;魏氏复合骨由前方椎体上方的第二骨化中心形成,这个骨化中心与第三和第四上神经骨相当。另一方面,胭脂鱼幼体的第二椎体副突已与第四椎体的胸肋相接;魏氏复合骨的扩展是骨化中心背脊部均匀地发生的,这些与鲤科有着明显的不同。鲤科幼体的魏氏复合骨发育具有共同的特点,第二骨化中心的前方有一棘状物在早期出现,它代表了第三上神经骨伸出部份。但随后的发育可以区分为两种不同方式:一种为雅罗系鱼类所具有,即第二骨化中心以棘状物的扩展为主,前、后棘存在并有缝合线相连;另一种为鲃系鱼类所有,即第二骨化中心的发育以其背中部伸出的实心嵴突为主,仅有不发达的前棘,此系属于派生性结构。与魏氏复合骨相关的是2—3椎体间的关系也有相应的差别:雅罗系鱼类的幼体其2—3椎体间分离(仅鳑(鱼皮)亚科鱼类例外),而鲃系鱼类的幼体其2—3椎体愈合。由于幼体魏氏复合骨与椎体的特征比成体表现更为明显,它们在系统发育上能提供更为清楚的信息。     

微囊藻毒素在小鼠肝脏积累并影响其超微结构

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海、淡水养殖日本鳗鲡肌肉和鱼皮营养分析比较

为了比较海、淡水养殖日本鳗鲡(Anguilla japonica)肌肉和鱼皮营养成分差异, 采用生物化学方法对海水与淡水养殖日本鳗鲡肌肉和鱼皮的一般营养成分、氨基酸含量、脂肪酸含量和矿物质含量进行测定与分析。结果显示, 海、淡水养殖日本鳗鲡鱼皮的水分、粗蛋白和灰分含量均显著性低于肌肉(P0.05), 但鱼皮粗脂肪含量显著高于肌肉(P0.05)。淡水养殖日本鳗鲡肌肉的粗蛋白含量显著性高于海水养殖日本鳗鲡(P0.05)。海、淡水养殖日本鳗鲡肌肉总氨基酸含量分别为50.22%和54.10%, 鱼皮总氨基酸含量分别为42.56%和45.80%。海、淡水养殖日本鳗鲡鱼皮呈鲜味氨基酸占氨基酸总量显著性高于肌肉(P0.05)。海、淡水养殖日本鳗鲡肌肉和鱼皮均以不饱和脂肪酸为主(65.96%67.51%), 并以单不饱和脂肪酸C18: 1n9含量为主(38.64%44.79%)。海水养殖日本鳗鲡肌肉矿物质元素(Fe、Ca、Cu、Na)和鱼皮矿物质元素(Fe、Mn、Na)的平均含量均显著高于淡水养殖日本鳗鲡(P0.05), 但Zn含量显著低于淡水养殖日本鳗鲡(P0.05)。研究表明, 不同养殖环境的日本鳗鲡肌肉和鱼皮营养成分丰富, 淡水养殖日本鳗鲡肌肉和鱼皮的氨基酸含量和脂肪酸组成方面稍优于海水养殖日本鳗鲡, 而海水养殖环境日本鳗鲡肌肉和鱼皮的矿物质元素含量得到较高的富集。