槐种子发育中胚乳细胞半乳甘露聚糖积累的研究

槐 ( Sophora japonica L.)开花约 60 d至种子成熟 ,为胚乳半乳甘露聚糖积累期。用组织化学方法 ,对储藏于胚乳细胞壁上的半乳甘露聚糖的形成积累进行了观察 ,结果表明 ,半乳甘露聚糖最先在邻近胚的胚乳细胞的粗面内质网的囊泡腔内形成 ,并通过细胞质膜分泌至细胞壁周围。此后 ,半乳甘露聚糖的积累逐渐向种皮方向扩展 ,及至种子成熟时 ,除糊粉层外 ,所有胚乳细胞几乎全由多糖所填充。此外 ,对半乳甘露聚糖发生部位及其积累过程的消长变化进行了讨论     

大豆黄酮对大鼠乳腺发育作用的实验研究

本文研究了大豆黄酮对大鼠乳腺发育及其对垂体生长激素（ＧＨ）和催乳素（ＰＲＬ）分泌的影响，结果表明：１）胃饲或皮下注射大豆黄酮能显著提高去卵巢大鼠或正常处女大鼠乳腺重量和乳腺ＤＮＡ、ＲＮＡ含量；２）胃饲或皮下注射大豆黄酮能显著提高正常处女大鼠血清ＧＨ和ＰＲＬ含量，３）大豆黄酮能显著提高大鼠乳腺，垂体和下丘脑胞浆雌二醇受体的数目，并显著提高乳腺孕酮受体的数目，体外受体竞争结合试验结果表明：大豆黄酮与大     

THE INFLUENCE OF ENVIRONMENTAL LIGHTING ON THE GROWTH AND PROMETAMORPHIC DEVELOPMENT OF LARVAL RANA PIPIENS

This study was designed to investigate whether the larval development of an anuran amphibian could be modified by raising the animals in continuous light or darkness instead of under conditions of diurnal illumination, and to quantify the effects of these treatments at various intervals during this period of development.
Larvae of the frog, Rana pipiens , were raised through metamorphosis under conditions of constant light, constant darkness, or diurnal lighting. As measured by stages of development, body weight, tail length and body length at 20-day intervals, no significant differences in growth rate or metamorphic change were observed until near the middle of the prometamorphic period, which began at approximately the 50th day of development. After midmetamorphosis, a significant acceleration in the measured parameters was seen for the animals raised in conditions of constant light in comparison with those in constant darkness. Those with diurnal lighting were intermediate.
These results suggested that light, or its absence, can respectively stimulate or retard amphibian metamorphosis in late larval stages after the hypothalamo-hypophyseal-thyroid axis has matured. Neither continuous light nor continuous darkness during larval development prevented the transformation from tadpole to frog.     

ADAPTIVE GENETIC VARIATION IN GROWTH AND DEVELOPMENT OF TADPOLES OF THE HYBRIDOGENETIC RANA ESCULENTA COMPLEX

The distribution and proportion of the sexual species Rana lessonae to the hemiclonal hybrid R. esculenta among natural habitats suggests that these anurans may differ in adaptive abilities. I used a half-sib design to partition phenotypic and quantitative genetic variation in tadpole responses at two food levels into causal variance components. Rana lessonae displays strong phenotypic variation across food levels. Growth rate is strictly determined by environmental factors and includes weak maternal effects. Larval period and body size at metamorphosis both contain moderate levels of additive genetic variance. The sire x food interactions and the lack of environmental correlations indicate that adaptive phenotypic plasticity is present in both of these traits. In contrast, R. esculenta displays less phenotypic variation across food levels, especially for larval period. Variation in body size at metamorphosis is underlain by genetic variation as shown by high levels of additive genetic variance, yet growth rate and larval period are not. Significant environmental correlations between larval period at high food level and growth, larval period, and body size at low food, indicate phenotypic plasticity is absent. A positive phenotypic correlation between body size at metamorphosis and larval period for R. lessonae at both food levels suggests a trade-off between growing large and metamorphosing quickly to escape predation or pond drying. The lack of a similar correlation for R. esculenta at the high food level suggests it may be less constrained. Different levels of adaptive genetic variation among larval traits suggest that the sexual species and the hybridogenetic hemiclone differ in their abilities to cope with temporally and spatially heterogeneous environments.     

THE DEVELOPMENT OF SURFACE SPECIALIZATION IN THE SECRETORY EPITHELIUM OF THE AVIAN SALT GLAND IN RESPONSE TO OSMOTIC STRESS

Cell surface specialization, a characteristic common to most ion-transporting epithelia, was studied in the salt (nasal) gland of the domestic duck in relation to osmotic stress. Three days after hatching, experimental ducklings were given 1% NaCl to drink for 12 hr and freshwater for the remainder of each day. Control ducklings were maintained exclusively on freshwater. The fine structure of the secretory epithelium was examined on various days of the regimen. The nasal gland epithelium of the secretory lobule is composed of several types of cells. Peripheral cells, lying at the blind ends of the branched secretory tubules, are similar in both control and experimental animals at all stages of glandular development. These generative cells contain few mitochondria and have nearly smooth cell surfaces. Partially specialized secretory cells predominate in the secretory tubules of control animals and appear as transitional cells in the tubular epithelium of salt-stressed animals. These cells contain few mitochondria and bear short folds along their lateral cell surfaces. Fully specialized cells dominate the secretory epithelium of osmotically stressed ducklings. The lateral and basal surfaces of these cells are deeply folded, forming complex intra- and extracellular compartments. This vast increase in absorptive surface area is paralleled by an increase in the number of mitochondria that pack the basal compartments. The development of this fully specialized cell is correlated with the marked increase in (Na⁺-K⁺)-ATPase activity in the glands of osmotically stressed birds.     

ACROSOMIC REACTION AND PROTEOLYTIC ACTIVITY IN THE SPERMATOZOA OF AN ANURAN AMPHIBIAN, LEPTODACTYLUS CHAQUENSIS (CEI)

Acrosomal reaction and acrosomal protease release in Leptodactylus chaquensis are correlated. When spermatozoa are included in gelatin films, the characteristic digestion halos around the sperm head can be observed only after the acrosomic reaction is accomplished. The addition of 10 mM EDTA to the gelatin films arrests the acrosomic reaction and no digestion halo is formed. Crude enzymatic preparations containing acrosomal proteases are equally active on gelatin and BAPNA substrates, irrespective of the presence of EDTA. Trypsin inhibitors (ovomucoid, lima bean and soybean) produce both diminution of the digestion halo and lowering of the activity of crude enzymatic preparations on gelatin or BAPNA substrates.     

人肾上腺内肽能神经的超微结构

应用抗生蛋白链菌素一生物素一过氧化物酶复合物的免疫电镜技术,在相邻切片中,分别观察人肾上腺内ＮＰＹ、ＶＩＰ、ＳＰ和ＣＧＲＰ免疫反应神经纤维的超微结构和免疫反应物的定位。ＮＰＹ和ＶＩＰ免疫反应物位于小颗粒羹泡和线粒体外膜,部分嗜铬细胞呈ＮＰＹ免疫反应阳性。ＳＰ和ＣＧＲＰ免疫反应物主要定位于大颗粒囊泡内。ＳＰ和ＣＧＲＰ免疫反应轴突与嗜铬细胞形成对称性或非对称性的轴体突轴。测量了这４种肽能神经末梢的直径,从而推测其来源,并讨论了该４种神经肽对人肾上腺的作用。     

GENETIC VARIATION FOR LARVAL ANURAN (SCAPHIOPUS COUCHII) DEVELOPMENT TIME IN AN UNCERTAIN ENVIRONMENT

Couch's spadefoot toads (Scaphiopus couchii) breed in ponds of uncertain duration. In natural ponds, larvae exhibit considerable variation in growth, size at metamorphosis, and development time. Phenotypic differences in development time may dramatically affect survivorship in these ponds. A quantitative-genetic analysis of larval traits was undertaken to determine the potential evolutionary relevance of phenotypic variation observed in the field. Additive genetic variance was detected for development time, but not for any other trait. Some variation in early growth was attributed to maternal effects; maternal effects, however, were not apparent for size at metamorphosis or development time. Nonadditive genetic effects were not statistically significant for any trait, but the nonsignificance of these effects must be interpreted cautiously, as the sample of females was relatively small and the mating design used is not very effective for detecting interactions. Genetic variation in development time in this population is most likely maintained by variability in the direction of selection as a consequence of variation in pond duration.     

泽蛙单倍体细胞RNA含量对胚胎发育和成活的影响

对两栖类单倍体的综合症以及死亡原因,前人有许多不同认识,本文用实验说明,单倍体细胞的RNA含量不及二倍体的一半,并认为,单倍体泽蛙的死亡原因与其细胞中RNA含量不足密切相关。     

EFFECT OF ECDYSONE ON THE OVARIAN DEVELOPMENT OF BOMBYX SILKWORM*

From the ligation experiments, it is indicated that the secretion from prothoracic glands during early pupal period induces the ovarian development in female pupa of the silkworm, Bombyx mori. The exogenous β-ecdysone injected into isolated pupal abdomen also induces the initiation of the ovarian development.     

THE ONTOGENETIC DEVELOPMENT OF THE SOMATIC MUSCULATURE OF THE TRUNK OF THE AGLOSSAL ANURAN XENOPUS LAEVIS (DAUDIN)

The secondary somatic muscles of the trunk develop by means of proliferations from the primary muscles. The dorsal part of the "Urwirbelfortsatz" contains the elements of both the m. obliquus abdominis internus and m. obliquus abd. externus. The m. ileolumbalis of the adult is formed by the fusion of the m. ileolumbalis, pars medialis and pars lateralis. A separate m. coccygeo-sacralis is present in the young post-metamorphic stage. A true horizontal myoseptum is absent. A well-developed m. rectus abdominis superficialis can be distinguished during metamorphosis and even in the young post-metamorphic stage. The ontogenesis proves the allegedly primitive features concerning the m. rectus abdominis, the m. ileolumbalis and the m. coccygeo-sacralis to be specializations. Xenopus must be regarded as a very specialized anuran.     

CHANGES IN CALCIUM CONCENTRATIONS OF SERUM AND COELOMIC FLUID OF THE BULLFROG, RANA CATESBEIANA, DURING LARVAL DEVELOPMENT AND METAMORPHOSIS

The serum calcium levels of bullfrog tadpoles (stage 26 to 33) and adults are higher than those of the coelomic fluid. The serum levels increase gradually from stage 26 (7.6 mg/100 ml) to stage 30 (8.4 mg/100 ml), and then sharply to stage 33 (10.5 mg/100 ml), while the coelomic fluid levels increase from 7.1 to 8.7 mg/100 ml during this period. Only minor differences are found in serum and coelomic fluid sodium levels among larval stages with the exception of a temporary decrease during metamorphic climax.
These results suggest that the adult type of regulation of serum calcium concentrations is established during larval development and is fully achieved after the completion of metamorphosis. The control mechanism for serum calcium may be different from that for coelomic fluid.     

AN ELECTRON MICROSCOPE STUDY OF THE GLAND CELLS OF THE MINK ENDOMETRIUM

Portions of mink endometrium in delayed implantation, early postimplantation, and pseudo pregnancy were fixed in buffered osmium tetroxide with sucrose, or potassium permanganate. After rapid dehydration the portions of endometrium were embedded in either methacrylate or epoxy resin. Examination of the cells from the body of the glands of the endometrium of delayed implantation revealed the presence of prominent terminal bars, numerous secretion granules, and membrane discs in the apical region of the cell. In the supranuclear and infranuclear regions, mildly dilated cisternae of the endoplasmic reticulum were present, and in many cells unusually large mitochondria were seen. Numerous changes were noted in the gland cells of the post implantation stage. The endoplasmic reticulum in the basal region was extensively dilated, and the nuclei were situated more centrally. Giant mitochondria were no longer present. The large secretion granules were not present, but smaller granules were seen, especially in the Golgi region. Some of the Golgi cisternae were dilated and the pattern of parallel membranes was consequently less distinct. It is suggested that gland cells in the postimplantation and pseudopregnancy stages exhibit evidence of greater secretory activity than those in the delayed implantation stage.     

AN ULTRASTRUCTURAL STUDY OF THE GLAND OF LEIBLEIN OF MURICID AND NASSARIID NEOGASTROPODS IN RELATION TO FUNCTION, WITH A DISCUSSION ON ITS HOMOLOGIES IN OTHER CAENOGASTROPODS

The gland of Leiblein of the muricid Nucella lapillus and thenassariid Hinia reticulata has been examined by scanning andtransmission electron microscopy. The origin and functionalsignificance of its complex organization and its relationshipwith the rest of the mid-oesophagus in Nucella are discussed.It is absorptive as well as secretory, and a mechanism is proposedby which solute-rich fluids may enter the gland. Its epitheliumis composed of occasional mucous cells and two major cell types:ciliated cells engaged in protein metabolism and unciliatedcells responsible for uptake and storage of lipids and carbohydrates,both of which show evidence of pinocytotic uptake of solutesand intracellular digestion in lysosomes. Some enzyme activitypersists in the residual bodies they shed by apocrine secretion,but they remain intact in a mucous string until they reach thestomach. Preliminary ultrastructural examination indicates thatthe gland absorbs cadmium not only from the blood but also directlyfrom its lumen and that it may have the capacity to sequestera wide range of toxins. The same types of cell occur in Hiniain which their cyclical activity has been correlated with feeding.Similar cells have been identified in the oesophageal glandsof other prosobranchs. The foregut glands of carnivorous caenogastropodsare compared with the gland of Leiblein. There is an inversecorrelation between the role of the mid-oesophagus in digestionand absorption and the complexity of the stomach. (Received 16 August 2004; accepted 24 January 2005)