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41.
Mogens L. Glass Atsushi Ishimatsu Kjell Johansen 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1986,156(3):425-430
Summary The snake-head fish (Channa argus) is an obligate air-breather inhabiting fresh waters in the temperate zone of East Asia.Ventilation of the air-breathing organ and aerial gas exchange were measured in 1 to 2 kg specimens at 15 and 25°C. Additionally, the ventilatory responses to hypoxia and hypercapnia were studied. Aerial ventilation increased from 1.1 to 2.9 mlbtps·kg–1·min–1 when temperature rose from 15 to 25°C. Concomitantly, O2-uptake through airbreathing increased from 0.1 mlstpd·kg–1·min–1 (15°C) to 0.28 mlstpd·kg–1·min–1 (25°C), whereas aerial gas exchange was less important for CO2-climination as evident from low gas exchange ratios (0.16 at 15°C, 0.29 at 25°C).Ventilation increases only slightly in response to inspiration of hypercapnic gas mixtures or to hypoxic conditions in water. By contrast, inspiration of hypoxic gas mixtures caused marked increases of ventilation in particular at the higher temperature.Aerial ventilation inChanna is low compared to values for ectothermic pulmonary breathers. However, its ventilatory responses to hypoxia strikingly resemble those of reptiles: The most marked ventilatory response to hypoxia occurs at the higher temperature where the demands for O2 are greatest. 相似文献
42.
N Kojima N Ueno M Takano H Yabushita M Noguchi M Ishihara K Yagi 《Biotechnology and applied biochemistry》1986,8(5):471-478
Sulfatide-containing liposomes showed the highest degree of adriamycin entrapment of all the liposomes tested. Adriamycin was bound to the sulfatide anions on the liposomal membrane, inserted into the membrane, and incorporated into the aqueous compartment of the vesicle. Liposome-entrapped adriamycin was maintained at a much higher blood level than free adriamycin, and reached a lower concentration in the heart than did the free drug, which might lead to lower cardiotoxicity of the drug. Incorporation of adriamycin into ovarian tumor transplanted into nude mice was increased when entrapped by the sulfatide-containing liposomes. Liposome-entrapped adriamycin did not induce the drastic loss of body weight which occurred with the free drug. The growth of ovarian tumor was inhibited by liposome-entrapped adriamycin to the same degree as free adriamycin. Having these advantages, sulfatide-containing liposomes could be useful carriers of adriamycin for cancer chemotherapy. 相似文献
43.
Coordination of flagella on filamentous cells of Escherichia coli. 总被引:12,自引:7,他引:5
Video techniques were used to study the coordination of different flagella on single filamentous cells of Escherichia coli. Filamentous, nonseptate cells were produced by introducing a cell division mutation into a strain that was polyhook but otherwise wild type for chemotaxis. Markers for its flagellar motors (ordinary polyhook cells that had been fixed with glutaraldehyde) were attached with antihook antibodies. The markers were driven alternately clockwise and counterclockwise, at angular velocities comparable to those observed when wild-type cells are tethered to glass. The directions of rotation of different markers on the same cell were not correlated; reversals of the flagellar motors occurred asynchronously. The bias of the motors (the fraction of time spent spinning counterclockwise) changed with time. Variations in bias were correlated, provided that the motors were within a few micrometers of one another. Thus, although the directions of rotation of flagellar motors are not controlled by a common intracellular signal, their biases are. This signal appears to have a limited range. 相似文献
44.
45.
Effects of Some Growth Regulators and Benzoic Acid Derivatives on Flower Initiation and Root Elongation of Pharbitis nil, Strain Kidachi 总被引:1,自引:0,他引:1
Seedlings of Pharbitis nil, strain Kidachi, were grown undercontinuous light at 20°C in vessels containing 5,000-mlnutrient solution, 24 plants per vessel. NAA (0.0050.5µM), GA3 (0.10.5 µM), kinetin (0.55µM), benzyladenine (0.055 µM) or abscisicacid (4 µM) added to the nutrient solution induced long-dayflowering, and the flowering was always accompanied by suppressionof root elongation. 3,4-Dichlorobenzoic acid (0.0510µM) and some other benzoic acid derivatives which arehighly effective for the induction of flowering in Lemna paucicostataalso showed similar effects. Neither NAA, kinetin nor 3,4-dichlorobenzoicacid applied via the apical part of the hypocotyl could causeflowering or suppression of root elongation. Thus, the flower-inducingeffect of the above substances was presumed to be secondaryto the suppression of root elongation. Ethrel (150 µM)added to the nutrient solution suppressed root elongation, butdid not induce flowering probably because it has flower-inhibitingactivity.
1 This paper is dedicated to the memory of Dr. Joji Ashida,the first president of the Japanese Society of Plant Physiologists. (Received December 15, 1982; Accepted February 25, 1983) 相似文献
46.
Effect of lipoxygenase inhibitors, AA-861 and T-22083, on chemical mediators released from sensitized guinea-pig lung tissue 总被引:1,自引:0,他引:1
Male Hartley strain guinea pigs weighing about 200g were used as the experimental animals. Histamine and SRS-A released from the lung tissue were measured by the bioassay methods. The amount of histamine released from passively sensitized lung tissue by the challenge of antigen showed marked decrease by preincubating with AA-861 or T-22083, and the percentage inhibition by AA-861 was greater than that by T-22083. The amount of SRS-A released from sensitized lung tissue by the challenge with antigen showed marked decrease by preincubation with AA-861 or T-22083, and the percentage inhibition by AA-861 was greater than that by T-22083. The above results suggest that AA-861 and T-22083 have not only an inhibitory action on the release of SRS-A from sensitized lung tissue but also have an inhibitory action on the release of histamine. 相似文献
47.
Atsushi Imai Hiroaki Hattori Masaru Takahashi Yoshinori Nozawa 《Biochemical and biophysical research communications》1983,112(2):693-700
The regulation of human platelet responses by cyclic AMP (cAMP) has been investigated by measuring thrombin-stimulated serotonin release, Ca2+ uptake and phospholipase activity. Thrombin-induced 1,2-diacylglycerol (DG) formation as a result of phospholipase C activation was inhibited by pretreatment with dibutyryl cAMP (dbcAMP) in a dose-dependent manner. Subsequent failure to produce phosphatidic acid (PA), which is converted from 1,2-DG by phosphorylation and would serve as intracellular Ca2+ ionophore, appeared to parallel the decrease in Ca2+ uptake activity. Phospholipase A2 activity, monitored by the production of [3H]lysophosphatidylcholine and [3H]lysophosphatidylethanolamine, was also suppressed by dbcAMP. These data indicate that the intracellular cAMP level may be closely associated with Ca2+ uptake and phospholipases activation. In addition, it is suggested that alteration of intracellular cAMP regulates phospholipase activation and consequently platelet responses, perhaps by controlling available Ca2+ content. 相似文献
48.
Hiroshi Ashihara Atsushi Komamine Masami Shimokoriyama 《Journal of plant research》1974,87(2):121-131
Changes in activities of the glycolytic and pentose phosphate (PP) pathways in glucose catabolism in various parts of the
hypocotyls obtained from 4-day-old etiolatedPhaseolus mungo seedlings were investigated by measuring the inhibition rates of respiration by iodoacetate and malonate, and the release
of14CO2 from [1-14C]- and [6-14C]glucose. The relative activity of the PP pathway in glucose catabolism was higher in the immature part (Part I) and the
aged part (Part V) of the hypocotyls than in the intermediary one (Part III), while the activity of the glycolytic pathway
decreased with aging.
On a fresh weight basis, the enzyme activities of the glycolytic and PP pathways were higher in Part I than in Parts III and
V. On a protein content basis, however, activities of the enzymes of the PP pathway increased with aging and differentiation
of the hypocotyls whereas those of the glycolytic pathway decreased. Levels of nicotinamide adenine nucleotides were found
to be in the following order: Part I>Part III> Part V for NAD++NADH; Part I>Part V>Part III for NADP++NADPH. The stimulative effect of methylene blue on decreasing the C6/C1 ratio was greater in Part III than in Part I, and No effect was observed in Part V.
These data suggest that a decrease in the activity of the glycolytic pathway with aging and differentiation may be due to
the decreasing glycolytic enzyme activities and NAD(H) content. The higher activity of the PP pathway in the immature part
is attributable to larger amounts of NADP(H) and enzymes of the PP pathway. The greater contribution of the PP pathway to
glucose catabolism in the aged part than in the intermediary part seems to results from a more active turnover of NADP and
the relatively higher activity of the enzymes of the PP pathway than those of the glycolytic pathway. 相似文献
49.
50.
Establishment of five human myeloma cell lines 总被引:3,自引:0,他引:3
Masayoshi Namba Takemi Ohtsuki Masaharu Mori Atsushi Togawa Hideho Wada Takashi Sugihara Yoshihito Yawata Tetsuo Kimoto 《In vitro cellular & developmental biology. Plant》1989,25(8):723-729
Summary Five human myeloma cell lines, KMM-1, KMS-5, KMS-11, KMS-12- PE, and KMS-12-BM, have been established at Kawasaki Medical
School since 1980. As the KMS-12-PE and KMS-12-BM lines were obtained from the same patient, these five cell lines have been
derived from four patients with multiple myeloma. The five myeloma cell lines are stably growing at present in RPMI 1640 medium
supplemented with 10% fetal bovine serum. They can also grow in a defined culture medium without serum. That these cell lines
were, human myeloma cells was confirmed by the following findings. Ultranstructually, all five cell lines showed features
characteristic of plasma cells. KMM-1 and KMS-11 cells secreted lambda and kappa chains into the culture medium, respectively,
but the other cell lines produced no immunoglobulins. KMM-1 expressed cytoplasmic lambda antigen, KMS-5 showed cytoplasmic
delta, and KMS-11 expressed surface kappa, whereas KMS-12-PE and KMS-12-BM cells showed no surface or cytoplasmic immunoglobulins.
Regarding reaction with a monoclonal plasma cell antibody (PCA-1), four of the five lines were positive, the exception being
KMS-5. Another monoclonal antibody (CD38), which also recognizes plasma cells, reponded to KMM-1, KMS-12-PE, and KSM-12-BM.
KMS-5 cells expressed acute lymphoblastic leukemia antigens (CALLA). These data suggest that such lines as KMM-1, KMS-11,
KMS-12-PE, and KMS-12-BM represent later stages of B-cell differentiation, and that KMS-5 represents a relatively early stage
of B-cell differentiation. All the cell lines lacked Epstein-Barr virus nuclear antigen, showed abnormal karyotypes of human
origin, and differed from each other in the isozyme patterns examined. Only KMS-5 was tumorigenic when transplanted subcutaneously
into nude mice. 相似文献