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11.
Changes in Crassulacean Acid Metabolism of Kalanchoe blossfeldiana by Different Nitrogen Sources 总被引:2,自引:0,他引:2
Kalanchoe blossfeldiana Poelln. cv. Hikan (a Crassulacean acidmetabolism (CAM) plant) was grown in pots containing soil for6 months and then cultured in nutrient solution containing 10mM nitrate or ammonium as a sole nitrogen source for 2 or 3months, under a long-day (16 h) condition. Plant growth was better in the nitrate medium. Leaves of thenitrate-grown plants showed greater diurnal fluctuations intitratable acidity and malate content than those of the ammonium-grownplants. The diurnal patterns in CO2 exchange of nitrate-grownplants were basically similar for both groups, but the amountof net CO2 uptake at night was twice as large in the nitrate-grownplants. The leaves of the nitrate-grown plants had 1.3 to 2.5times higher activities of phosphoenolpyruvate carboxylase (PEPC),phosphofructokinase (PFK) and NAD glycelaldehyde-3-phosphatedehydrogenase (G3PDH). These results indicate that K. blossfeldianagrown in nitrate medium showed more CAM activity than thosein ammonium medium. (Received August 13, 1987; Accepted February 22, 1988) 相似文献
12.
13.
Kiyoshi Takahashi Katsuya Miyatani Hiroyuki Yanai Ho Jong Jeon Kotaro Fujiwara Tadashi Yoshino Kazuhiko Hayashi Tadaatsu Akagi Ken Tsutsui Koichi Mizobuchi 《Virchows Archiv. B, Cell pathology including molecular pathology》1992,62(1):105-113
Monocytic leukemia (MoL) cells were obtained from the peripheral blood of a patient in whom the leukemic cells infiltrating
various lymphoreticular organs exhibited features intermediate between interdigitating reticulum cells (IDC) and ordinary
phagocytic macrophages, whereas the leukemic cells in the peripheral blood were essentially monocytic and lacked such features.
Peripheral blood CD4+ T-cells were established as an interleukin-2-dependent T-cell line. When the MoL cells were exposed
for a few days to conditioned medium from the T-cell line, they extended several dendritic cytoplasmic projections and became
intensely positive for HLA-DR antigen, cytoplasmic S-100β protein, and CD1 antigen. Functionally, the conditioned medium significantly
down-regulated Fc-mediated and Fc-independent phagocytic activities, and the levels of lysosomal enzymes such as lysozyme
and nonspecific esterase in the MoL cells. Moreover, the conditioned medium significantly up-regulated the accessory cell
function of the MoL cells as measured by the primary allogenic mixed leukocyte reaction (MLR). Furthermore, the conditioned
medium significantly down-regulated the expression of CD14 antigen.
Biochemical analysis indicated that the factor responsible for these changes is a protein which is distinct from known human
cytokines and whose molecular weight is approximately 31 kDa. These findings suggest that IDC are closely related the monocytic
lineage and that helper T-cells play an important role in constructing the microenvironment of T-lymphoid tissues which is
necessary for the differentiation and maturation of IDC. 相似文献
14.
The second-order rate constant (k4) for the oxidation of monosubstituted phenols and anilines by lactoperoxidase compound II was examined by Chance's method [B. Chance, Arch. Biochem. Biophys.
71 (1957), 130–136]. When the electronic states of these substrates were calculated by an ab initio molecular orbital method, it was found that the log k4 value correlates well with the highest occupied molecular orbital (HOMO) energy level but not with the net charge or frontier electron density. These results are essentially similar to those reported previously in the case of horseradish peroxidase [J. Sakurada, R. Sekiguchi, K. Sato, and T. Hosoya, Biochemistry
29 (1990), 4093–4098], showing some dissimilar features which are considered to reflect the structural difference between the two enzymes.Abbreviations HOMO
highest occupied molecular orbital
- HRP
horseradish peroxidase
- LPO
lactoperoxidase (EC 1.11.1.7)
- LUMO
lowest unoccupied molecular orbital 相似文献
15.
Koichi Negayama Takako Negayama Kiyomi Kondo 《International journal of primatology》1986,7(4):365-378
Parturitional behavior in 12 caged Macaca fuscatawas analyzed. Wild-caught mothers showed adequate maternal behaviors immediately following the neonate’s expulsion. Parity
differences existed in the behaviors; primiparae were more idiosyncratic than were multiparae. Among multiparae, those with
two or more offspring were uniformly adequate, but those with a single birth experience varied in the adequacy of the maternal
care they provided at parturition. Mothers embraced and licked their neonates and had ventroventral contact with them frequently
immediately after parturition but decreased these behaviors after expulsion of the placenta. In contrast, mothers showed allogrooming
after consuming the placenta. Placentophagy was correlated with the level of orality represented by maternal licking behaviors.
An isolation-reared primipara reacted to her newborn in a basically negative manner, although she showed little actual aggression.
She showed a rapid shift in her negative behavior during the immediate postpartum period. This mother’s newborn sought contact
with her, indicating the neonate’s active role in establishing a stable mother-neonate bond. 相似文献
16.
17.
Stereospecific hydroxylation of 3-deoxy-1,2:5,6-di-O-isopropylidene-3-C-trans-and 3-C-cis-(methoxycarbonylmethylene)-α-D-ribo-hexofuranose (2 and 3, respectively), with potassium permanganate in pyridine afforded 3-C-[S- and R-hydroxy-(methoxycarbonyl)methyl]-1,2:5,6-di-O-isopropylidene-α-D-glucofuranose, (6 and 7, respectively), in a combined yield, after chromatography, of 43%. Selective formation of monomethanesulfonates (9a and 10a) and p-toluenesulfonates (9b and 10b), followed by treatment with sodium azide and reduction of the azide, afforded the methyl 2-D-(and 2-L-)(3-deoxy-1,2:5,6-di-O-isopropylidene-α-D-glucofuranos-3-yl)-glycinates (12a and 13a, respectively). Basic hydrolysis of the latter compounds yielded 2-D- and 2-L-(3-deoxy-1,2:5,6-di-O-isopropylidene-α-D-glucofuranos-3-yl)glycine (12b and 13b, respectively). The structures of the glycosyl amino acids were correlated with that of L-alanine by circular dichroism. 相似文献
18.
Koichi Iijima 《Cell and tissue research》1970,103(4):460-474
Summary Detailed histochemical studies have been conducted on the morphology of the Golgi apparatus by applying the thiamine pyrophosphatase technique (Novikoff and Goldfisher, 1961) to the neurons of supraoptic and paraventricular nuclei of normal and dehydrated rabbits. The neurons in both nuclei were classified into five categories on the basis of the morphology of the Golgi apparatus. The number of cells in individual categories were counted to evaluate the percentage of each category in the whole nucleus.Neurons have many vesicles which show the tendency to form clusters. Such clusters are present also in the basal bodies. The Golgi apparatus is localized near one side of the nucleus in many neurons. The neurons indicate phasic activity of resting, anabolic and catabolic stages under normal conditions.During dehydration, the Golgi apparatus went through the three stages of network formation, the increase of the budding-off process and later on disintegration. The supraoptic nucleus reacted to the TPPase test more severely than the paraventricular nucleus, whereas the former went through the stages more slowly than the latter. The paraventricular nucleus also revealed sensitivity to osmotic stress. 相似文献
19.
Summary The effect of competition pressure on the sequential pattern of adult emergence was studied by using the experimental population
of the azuki bean weevil. The density and pattern of emergence curves of the parental adult induced the changes in the shape
of emergence curve of the progeny as well as the number of progeny individuals. In order to explain these changes, a simple
mathematical model which has two independent variables, the population density and the capacity of environment, was introduced.
The model generated basically similar patterns of emergene curves as observed in the present experiments. This means that
the model displayed well the competition pressure which differentially acted upon early-born and late-born individuals in
the populations being at different densities and which were differentially received by individual progeny according to the
sequential distributions of parents. This different severity of competition pressure resulted in the difference of time when
the pressure compelled influences on the sequential distribution of adult emergence. Therefore, early developed individuals
may have good chance to survive, but the competition pressure works as a factor modifying their fundamental superiority, especially
in the scramble type of competition.
Intense crowding of the azuki bean weevil gave rise to the scramble type of competition in the relation between the numbers
of adults emerged in two successive generations. When parental emergence concentrated in a short term and at high density,
the competition becomes intense, resulting in the inferiority of early developed individuals, in the decrease in number at
the next generation and in the increase of duration for emergence. 相似文献
20.
Koichi Fujii 《Population Ecology》1965,7(2):118-125
- A theoretical model for the competition curve, which stands on a few simple assumptions, was proposed.
- Some applications were done to actual data, and during these applications the validity of the present model and its assumptions was discussed.
- From the present model it can be expected that there is a discrete competition mechanism even in the appearently continuous medium.