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1.
Osafune Tetsuaki; Mihara Sayoko; Hase Eiji; Ohkuro Isamu 《Plant & cell physiology》1972,13(2):211-227
Changes in subcellular structures during the entire vegetativecell cycle of Chlamydomonas reinhardi Dangeard in synchronousculture were followed with an electron microscope. Giant mitochondriaof various shapes were temporarily formed, probably by fusionof smaller mitochondria, in the algal cells at an intermediatestage of the growth phase of the cell cycle. Formation of giantmitochondria was accompanied by a marked decrease in the oxygen-uptakeactivity of cells. Giant mitochondria divided into smaller formsconcurrently with a re-increase in the oxygen-uptake activityof cells. Some characteristics of changes in the structuresof chloroplast, the nucleus, the endoplasmic reticula, flagellaand dictyosomes are described.
1 This work was reported in part at the 35th Annual Meetingof the Botanical Society of Japan, October 1970. (Received October 13, 1971; ) 相似文献
2.
Immunohistochemical localization of atrial natriuretic polypeptide (ANP) in human atrial and ventricular myocardiocytes 总被引:2,自引:0,他引:2
To date, there have been few immunohistochemical investigations of atrial natriuretic polypeptide (ANP) in human cardiac tissue, especially the ventricles. In this study, myocardial tissue was obtained from two sources: the bilateral atria and ventricles at autopsy; and biopsy tissues from the right auricle and left ventricle of a patient with myocardial infarction undergoing surgery. These tissues were examined by the avidin-biotin immunoperoxidase technique using three kinds of primary ANP-antibodies. ANP-immunoreactivity was observed in the perinuclear region of myocytes of all tissues examined. The intensity of the reaction was stronger in atrial tissue, weaker in ventricular tissue. In the later tissue, the positive-staining myocytes were not part of the pulse-conducting system. Although the tissues we studied were not obtained from normal hearts, our data demonstrates that ANP-reactivity can be detected in ventricular myocytes outside the pulse-conducting system. 相似文献
3.
Fluence-response relationships were examined for positive and negative phototropism induced by blue (450 nm) and ultraviolet-B (UV-B, 280 nm) light, respectively, in the Pilobolus crystallinus sporangiophore. Fluence-response curves for both blue and UV-B light obtained by changing the fluence by varying exposure time only showed the classical first and second positive bending. However, fluence-response curves obtained by varying the fluence rate were bell-shaped irrespective of the length of the exposure time. With increasing exposure time the peak became higher along the ascendant arm and the descendant arm was shifted toward the higher fluence. The Bunsen-Roscoe reciprocity law was valid only when the fluence was less than approx. 400 pmol·m-2 for both blue and UV-B light. Because the shapes of the fluence-response curves for blue and UV-B light were nearly the same, the photoreceptor systems for both blue and UV-B light are considered to be the same.Abbreviation UV-B
ultraviolet-B 相似文献
4.
H. Yamada Y. Saito M. Mukoyama K. Nakao H. Yasue T. Ban H. Imura Y. Sano 《Histochemistry and cell biology》1988,89(5):411-413
Summary To date, there have been few immunohistochemical investigations of atrial natriuretic polypeptide (ANP) in human cardiac tissue, especially the ventricles. In this study, myocardial tissue was obtained from two sources: the bilateral atria and ventricles at autopsy; and biopsy tissues from the right auricle and left ventricle of a patient with myocardial infarction undergoing surgery. These tissues were examined by the avidin-biotin immunoperoxidase technique using three kinds of primary ANP-antibodies. ANP-immunoreactivity was observed in the perinuclear region of myocytes of all tissues examined. The intensity of the reaction was stronger in atrial tissue, weaker in ventricular tissue. In the later tissue, the positive-staining myocytes were not part of the pulse-conducting system. Although the tissues we studied were not obtained from normal hearts, our data demonstrates that ANP-reactivity can be detected in ventricular myocytes outside the pulse-conducting system. 相似文献
5.
Cytosolic and mitochondrial surface factor-independent import of a synthetic peptide into mitochondria. 总被引:1,自引:0,他引:1
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We chemically synthesized a peptide, 11 beta-45, which was composed of 45 amino acid residues including the whole extension peptide and some of the mature portion of bovine cytochrome P-450(11 beta) precursor. 11 beta-45 was imported into mitochondria in vitro depending on the mitochondrial membrane potential, but its import did not require extramitochondrial ATP. Although cytosolic protein factors in the high speed supernatant of reticulocyte lysate are known to stimulate the import of various precursor proteins into mitochondria, the import of 11 beta-45 was not stimulated by cytosolic factors in reticulocyte lysate. The import of the peptide did not require mitochondrial surface protein components because its import was not affected by trypsin treatment of mitochondria. On the other hand, trypsin treatment of mitoplasts resulted in a great reduction in the import of the peptide, indicating that 11 beta-45 interacts during the import process with some protein components located inside mitochondria. These observations indicated that the peptide 11 beta-45 was imported via the potential-dependent pathway as in the case of precursor proteins, but skipped the interactions with cytosolic factors and mitochondrial surface components normally required for the import of precursor proteins. 相似文献
6.
Sadayuki Ban Shozo Iida Hachiro Shimba Akio A. Awa Suzanne M. Nowak Tsutomu Sugahara 《Biochemical and biophysical research communications》1983,113(1):142-147
Endoreduplication (ER) could be induced very effectively in Chinese hamster V79 cells exposed to cytosine arabinoside (1-β-D-arabinofuranosylcytosine; Ara-C). Cells were cultured for 48 hours in Ara-C containing medium. ER frequency increases rapidly after Ara-C release. About 60% of metaphase cells were endoreduplicated at 8–10 hours after release from Ara-C (5 μg/ml). Induction of ER also depends on Ara-C concentrations. 相似文献
7.
Obtusastyrene (4-cinnamylphenol) displays effective antimicrobial activity in vitro against a variety of gram-positive bacteria, yeasts, and molds. The activity of obtusastyrene is not appreciably affected by pH, and its minimal inhibitory concentrations, 12 to 25 mug/ml for bacteria and 12 to 100 mug/ml for fungi, compare favorably with those of a number of synthetic, phenolic antimicrobial agents. 相似文献
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