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111.
112.
Nobuhiko Saitô 《Cell biochemistry and biophysics》1987,11(1):321-329
The metling behavior of DNA and formation of α-helices and β-strands in protein can be discussed rigorously by statistical mechanical treatment. To do this, however, appropriate formulations are required for fast computer calculation. New formalisms for DNA and protein in terms of recurrence relations suitable for computer calculation are presented. 相似文献
113.
Summary The changes in ovarian activity in the life cycle of the eusocial halictine beeLasioglossum (Evylaeus) duplex (Dalla Torre) was studied in both queens and workers by examining the stages of the terminal follicle in each of the six ovarioles. By
this method, ovarian activities of both queens and workers were more quantitatively determined than by observation of gross
ovarian features as usually conducted. Queen ovaries clearly exhibited two active periods, corresponding to the spring solitary
phase and the summer eusocial phase, with distinctly greater activity in the latter. In ovaries of overwintering queens oosorption
of young follicle was observed. Worker ovaries were found more active in orphan than in queenright colonies. The order of
ovarian activity obtained from pooled data, summer queens>spring queens>orphan workers>queenright workers, was also recognized
by comparison of individual females.
Bionomics of the eusocial halictine beeLasioglossum duplex IX.
Contribution No. 3107 from the Inst. Low Temp. Sci. 相似文献
114.
115.
Jan Kopecký Josef Houštěk Eva Szarska Zdeněk Drahota 《Journal of bioenergetics and biomembranes》1986,18(6):507-519
The proteolipid subunit of H+-ATPase was labeled by [14C]N,N-dicyclohexylcarbodiimide in bovine heart mitochondria. The radioactive labeling was followed using various systems of sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE). When using discontinuous SDS-PAGE (Laemmli, U.K., 1970,Nature (London)227, 680–685) a monomeric (Mr 7600±1500) and a dimeric form (Mr 17,800±1200) of the proteolipid were detected, while only the monomeric form was found on urea (8 M) containing gels (SDS-PAGE according to Laemmli; or Swank, R. T., and Munkers, K. D., 1971,Anal. Biochem.
39, 462–477). When using SDS-PAGE with Na-Pi buffer (Weber, K., and Osborn, M., 1969,J. Biol. Chem.
244, 4406–4442), only a dimeric form of the proteolipid (Mr 15,000±1000) was detected. Experimental data indicate that the different patterns of proteolipid separation are related to the presence of the two distinct proteolipid conformations in the SDS solution. 相似文献
116.
Summary The behaviour of a drum fermentor and a column fermentor during the sporulation ofPenicillium roqueforti on buckwheat seeds is presented. The main problem encountered during the course of a cultivation is the free water released (about 0.1 ml/g dry matter) which must be removed from the medium. The rotation of the drum fermentor may disturb the growth and the sporulation. The column fermentor thus represents the best way to perform batch cultivation of the fungus: 109 external spores/g dry matter are obtained.Semi-continous cultivation, with sequential emptying and filling, is performed in 1-liter bottles. This kind of cultivation may give a maximal average productivity close to 9.2·106 external spores/g dry matter per hour. A drum fermentor, rotading only when emptying and filling, could represent an alternative to perform this kind of cultivation. 相似文献
117.
Max Kaufmann Jorgen Marqverson Kenneth E. Stanley Christian Mouritzen Hans Hvid-Hansen 《Cancer immunology, immunotherapy : CII》1986,22(1):56-61
Summary The distribution of Corynebacterium parvum labeled with 131iodine or 99mtechnetium was studied in 17 patients with bronchogenic carcinoma. The labeled bacteria were given intravenously or intrapleurally and monitored by whole-body gamma tracking and samples of blood and urine. Even though the rate of physical decay is quite different for 131iodine and 99mtechnetium, the tracking time of labeled bacteria was limited to 24 h after injection for both radioactive isotopes. Technetium labeling was preferred because of greater imaging resolution and less radiation dose to the patient. Following intravenous administration, labeled C. parvum was found predominantly in the liver and spleen, and in a lesser amount in the lung. Radioactivity was confined to the pleural cavity after intrapleural injection. These results suggest the combined intravenous and intrapleural route of adjuvant immunosupportive agents such as C. parvum for operable lung cancer patients. 相似文献
118.
Nucleotide sequence of the rice cytochrome f gene and the presence of sequence variation near this gene 总被引:1,自引:0,他引:1
The rice (Oryza sativa L. var. Labelle) chloroplast (cp) gene encoding cytochrome f has been isolated and sequenced. The coding region of this rice gene displays 95.1%, 85.3% and 85.2% nucleotide sequence homology with that of wheat, pea and spinach, respectively. To examine the cpDNA sequence variation in rice, cpDNA from Labelle and its parents, Belle Patna and Dawn was compared. Using the cytochrome f gene as the probe for hybridization, we found several differences in the size and number of restriction fragments in the cp genome of three rice varieties. An additional restriction fragment found in the Belle Patna cp suggests that this cp genome is either heterogeneous or contains two copies of cytochrome f gene per cpDNA. 相似文献
119.
Widespread mortality of the black sea urchin Diadema antillarum occurred in the Caribbean in 1983; beginning in Panama in January, and having its major impact at Barbados in September. Mortality on ten reefs surveyed in Barbados was 93.2%, with the highest being 99.9% and the lowest 86.9%. Mortality on each reef was independent of the pre-mortality density on the reef. Urchins with test diameters between 20 and 40 mm were more severely affected than smaller or larger urchins. Populations on reefs exposed to incoming oceanic water suffered heavier mortality than those on protected reefs. Mean size of urchins was smallest on high density reefs. This may indicate a negative effect of density on urchin growth. At post-mortality densities, urchins may grow faster and reach sexual maturity sooner. 相似文献
120.
P A Coulombe P R Filion M G C?té 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》1986,8(3):263-266
After administration to mice of butylated hydroxytoluene, the pulmonary alveolar epithelium adopts a biphasic pattern of regenerative proliferation. This hitherto-unnoticed pattern of epithelial repair in the lung was revealed by the investigation of stereologic parameters. The earliest evidence of epithelial injury involved the type I pneumocytes, whose necrosis and disappearance from the septal surface was shown by a lowered surface density (SV). Proliferation of the type II pneumocytes ensued: the volume density (VV) rose above normal soon after the onset of necrosis, only to decrease as the cells slowly differentiated into intermediate and then type I pneumocytes. A second peak of type II pneumocytes appeared as the denuding of septa persisted. This twofold proliferation was also shown by the numerical density count (NV). Differentiation into an intermediate pneumocyte was itself documented by the raised VV and SV values. These observations of a biphasic mode of proliferation of type II pneumocytes raise the question of an unsuspected, persistent action of the toxic agent within pulmonary alveoli and serve to document the homeostasis of epithelial regeneration. 相似文献