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91.
92.
The cytokinetic effects of carboplatin(CBDCA) on a human ovarian cancer cell line(KF-1) were examined by means of cell survival rate and flow cytometry in comparison with cisplatin(CDDP). CBDCA and CDDP exhibited dose dependent cytotoxicity on KF-1, and CBDCA showed compatible cell growth inhibition to that of 15 times concentration of CDDP in comparison with IC50 of 72 hrs after drug addition. From the analysis of cell cycle, CBDCA and CDDP inhibited cell cycle progression at G2 + M phase. CBDCA exhibited G2 + M phase block to that of 15 to 20 times the concentration of CDDP. We suggested that CBDCA had potential therapeutic activity against ovarian cancer, but should be evaluated carefully in the clinical use. 相似文献
93.
Y Kohgo Y Kanisawa S Sakamaki S Nojiri Y Ueno Y Ito Y Niitsu S Hosoi S Sato I Urushizaki 《Human cell》1988,1(1):54-59
Lymphokine activated killer (LAK) cells are generated by culture of lymphocytes with interleukin 2 (IL-2) in short term culture (3 to 5 days) and are used for adoptive immunotherapy for advanced cancer patients. The culture condition hitherto reported are essentially based on the rotating culture system, in which the maximum cell density was at 2 X 10(6) cell/ml and the cell recovery was usually less than 100%. The inability to induce LAK cells efficiently in vitro made the culturing of cells for therapy rather difficult and costly work because the mean infusion dose of LAK cells of one patient requires more than 1 X 10(10)/ml. We have therefore attempted to culture lymphocytes in 10 times higher concentration comparing with conventional methods. By using a new dialyzing culture system under continuous regulation of the amount of infused IL-2, nutrition medium, and pO2 and pCO2, we could culture cells at 2 X 10(7)/ml for more than 21 days and the resulted LAK cells showed a 100 times increase of activity on a per cell basis. By limiting dilution procedure, these killer cells mostly express T cell markers such as CD3 and CD8 but dose not express CD16. 相似文献
94.
95.
Summary The fine structure of the main excretory duct epithelium of the male mouse submandibular glands was investigated by scanning and transmission electron microscopy. Three principal cell-types were observed: type I and II, and basal cells. This epithelium was characterized by the presence of intercellular canaliculi. Type-I cells were the most numerous. They had an abundance of mitochondria, well-developed Golgi apparatus, a few electron-lucent lipid-containing granules and poorly developed basal infoldings. These cells were also characterized by many glycogen granules throughout the cytoplasm and abundant smooth endoplasmic reticulum in the apical cytoplasm. Type-II cells were the second most numerous. Their most characteristic feature was the presence of abundant heterogeneous lipid-containing granules having acid phosphatase activity at the periphery. They were concentrated in the infra- and supranuclear cytoplasm. The granules may be derived from mitochondrial transformation and seem to be a special kind of secondary autolysosome. Type-II cells also contained abundant mitochondria throughout the cytoplasm, much smooth endoplasmic reticulum in the apical cytoplasm, a well developed Golgi apparatus adjacent to the heterogeneous lipid-containing granules and no basal infoldings. Basal cells were situated adjacent to the basal lamina. They had a large nucleus and the cytoplasm was filled with glycogen granules. 相似文献
96.
Masayuki Nishida Hirotaka Nishijima Kazuya Yonezawa Isao Sato Teisuke Anzai Kohichi Okita Hisakazu Yasuda 《European journal of applied physiology and occupational physiology》1992,64(6):528-533
To assess exercise energy metabolism of forearm flexor muscles in rowers, six male student rowers and six control subjects matched for age and sex were studied using phosphorus-31 magnetic resonance spectroscopy (31P-MRS). Firstly, to adjust for the effect of differences in cross-sectional muscle area, the maximal cross-sectional area (CSAmax) of the forearm flexor muscles was estimated in each individual using magnetic resonance imaging. Multistage exercise was then carried out with an initial energy production of 1 J.cm-2 CSAmax for 1 min and an increment of 1 J.cm-2 CSAmax every minute to the point of muscle exhaustion. A series of measurements of 31P-MRS were performed every minute. The CSAmax was significantly greater in the student rowers than in the control subjects [19.8 (SD 2.2) vs 17.1 (SD 1.2) cm2, P less than 0.05]. The absolute maximal exercise intensity (J.min-1) was greater in the rowers than in the control subjects. However, the maximal exercise intensity per unit of muscle cross sectional area (J.min-1.cm-2) was not significantly different between the two groups. During mild to moderate exercise intensities, a decrease in phosphocreatine and an increase in inorganic phosphate before the onset of acidosis were significantly less in the rowers, indicating a requirement of less adenosine 5'-diphosphate to drive adenosine 5'-triphosphate production. The onset of acidosis was also significantly delayed in the rowers. No difference was observed in forearm blood flow between the two groups at the same exercise intensity (J.min-1.cm-2).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
97.
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
98.
Correlation between the virulence of Francisella tularensis in experimental mice and its acriflavine reaction was studied. The cultures derived from all four strains (Ebina, CMB2, Schu, and N9) that had long been subcultured on agar media yielded two types of colonies, i.e., acriflavine reaction-positive (acf+) and acriflavine reaction-negative (acf-) colonies. All acf+ colonies, regardless of their parent strains, were shown to be low virulent in mice. Acf- colonies were shown to be either high (Ebina, CMB2) or low (Schu, N9) virulent. The low-virulent acf- colonies gained virulence during several passages in mice, whereas the acf+ colonies remained low virulent even after the animal passages. 相似文献
99.
Toshiyuki Sato 《Ecological Research》1992,7(1):1-7
Gametophyte populations inAthyrium brevifrons were analysed with respect to population size and surviving area (%) of individual thalli in a transplant garden at Sapporo
during 5–26 April 1983, to study the safe-microsite for gametophyte establishment in nature. Spores dispersed in August 1982
germinated and grew into thalli of various widths (<10 mm); 10.3% of the thalli matured by early October 1982. Maturation
was attained by gametophytes of width 4–7 mm. The number of gametophytes gradually decreased with increasing width. By April
1983, 20.5% of total gametophytes were mature with a mode of 5–6 mm in width. The relative number of gametophytes with surviving
area of 2–20% increased and that of 85–100% decreased in accordance with collection days delayed until after snow-melt. Surviving
area (%) on gametophyte of all widths decreased with decreasing soil moisture contents. In particular, immature gametophytes
of 2–4 mm width showed a significant correlation (P<0.01) between soil moisture content and relative number of gametophytes with 0–20% surviving area and mean surviving area
(%) of every width of thalli. The spring desiccation might be a factor that reduces or limits gametophyte populations in nature. 相似文献
100.
Expression of prolactin gene in incubating hens 总被引:2,自引:0,他引:2