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61.
Summary Reduced glutathione evokes a feeding response, the tentacle-ball formation inHydra japonica. This response consists of at least 5 components (R1–R5). We raised 6 monoclonal antibodies (mAbs), each of which depressed a specific subset of these components, and we also examined the immunocytochemical localization of antigens with these mAbs at light microscopic level. The 2 mAbs that depressed R2 and R4 bound to the cnidocils of the desmoneme and the stenotele nematocytes; the 3 mAbs that depressed R5 bound to the apical surface adjacent to the cnidocils of the nematocytes; and the 2 mAbs that depressed R1 and R3 bound to the apical spot structures of unidentified cells in the ectoderm.Together with the specificity of the action of the mAbs on the behavioral response, the correspondence between the effects on the response and the structures visualized with these mAbs suggests that these structures include components of the receptor-effector system relevant to chemoreception.  相似文献   
62.
A genomic clone obtained from mouse liver DNA using a mouse cytokeratin EndoA cDNA probe revealed the complete sequence of the EndoA gene. The gene is divided into nine exons and the exon-intron pattern has been conserved compared to that of other type-II cytokeratin-encoding genes. The 5' upstream, 3' downstream and first and third introns contain potential regulatory sequences, including polyoma virus enhancer motifs (PEA1 and PEA3) and AP-1 elements. The 5' regions upstream of the EndoA, EndoB and Ck8 genes contain homologous sequences surrounding the TATA boxes. In addition, a CpG dinucleotide cluster region was located around the first exon. This CpG cluster region was found to be hypomethylated in endodermal PYS-2 cells, retinoic acid-treated F9 cells, and F9 embryonal carcinoma cells, but hypermethylated in BALB/C 3T3 fibroblast cells that do not express EndoA. These findings may provide a clue to understanding the molecular mechanisms of EndoA gene expression.  相似文献   
63.
A three-dimensional angiographic analysis of the deep palmar arterial arches and their correlating arteries in Cercopithecidae, Pongidae and Hominidae revealed the following features. In Cercopithecidae, 3 deep palmar arches are formed by the perforating branches of the 2nd dorsal metacarpal artery: 2 proximal arches (the catella volaris proximalis and the arcus volaris profundus) and 1 distal arch (the catella volaris distalis). The intermetacarpal arteries arise from the catella volaris proximalis and the palmar metacarpal arteries arise from the arcus volaris profundus. In Pongidae, the arches are formed by the perforating branches of the 1st dorsal metacarpal artery, and they are composed of only the catella volaris proximalis and catella volaris distalis. In Hominidae, the arches are formed by the perforating branches of the 1st dorsal metacarpal artery, and they consist of the arcus volaris profundus and an incomplete catella volaris distalis.  相似文献   
64.
The cDNAs encoding alpha 3-subunits of rat brain Na+,K+-ATPase and the neomycin resistance gene were incorporated into BALB/c 3T3 cells by the co-transfection method. Stably transformed cells were selected with 300 micrograms/ml of neomycin (G-418) for 6 weeks. Northern blot analysis using the 3'-non-translated region of the cDNA as a probe revealed that the alpha 3 mRNA appeared in transfected cells. Na+,K+-ATPase activity of the transfected cells was twice that of wild-type cells. Regarding ouabain sensitivity, the Na+,K+-ATPase showed two Ki values for ouabain (8 x 10(-8) and 4.5 x 10(-5) M) in transfected cells while wild-type cells displayed only the higher value. Ouabain sensitivity of Rb+ uptake also demonstrated two Ki values in the transfected cells (8 x 10(-8) and 4 x 10(-5) M) and a Ki in wild-type cells of 4 x 10(-5) M. It is concluded that alpha 3 is a highly ouabain-sensitive catalytic subunit of Na+,K+-ATPase. It is also suggested that ouabain sensitivity is exclusively determined by the properties of the alpha-subunit rather than the beta-subunit. This is the first report on the catalytic characteristics of the alpha 3 isoform of Na+,K+-ATPase.  相似文献   
65.
The water distribution in the pulvinus of Mimosa can be visualized by an NMR imaging technique. After stimulation of a Mimosa plant, water in the lower half of the main pulvinus disappeared, the water previously contained in this area seeming to be transferred to the upper half of the main pulvinus. Movement of the water in conjunction with Mimosa movement was visualized sequentially by a non-invasive NMR imaging procedure.  相似文献   
66.
The changes in cerebral metabolism in mice in severe hypoxia were investigated by analyses of changes in the levels of energy metabolites and near-infrared spectrophotometric assessment of the states of hemoglobin and cytochrome oxidase. Under 4.4% O2, the contribution of anaerobic ATP production was at most about 20% of the demand. However, the cerebral ATP level was kept at the control level until about 1 min before death. Pentobarbital anesthesia, which reduced the cerebral rate of metabolism, prolonged the survival time, although anaerobic ATP production still did not support ATP demand. Under these conditions, deoxygenation of hemoglobin and reduction of cytochrome oxidase proceeded rapidly within 1 min. Hemoglobin reached the maximum state of deoxygenation in the middle phase of hypoxia, with no further change until death. However, cytochrome oxidase was reduced slowly with one phase of partial reoxidation due to increase of cerebral blood volume, and reached the completely reduced state at death. From these results it was concluded that the aerobic ATP synthesis, which supplied more than 80% of the cerebral demand, decreased gradually because of limitation of oxygen supply, and that the failure of oxidative phosphorylation to meet demand triggered the decrease in the cellular ATP level that led to death.  相似文献   
67.
Seminal vesicle cells of neonatally castrated adult mice show poor response to androgen, compared to those of mice castrated at adulthood; effects of pretreatment with androgen or estrogen at adulthood on androgen-induced proliferation of the seminal vesicle cells were examined in neonatally castrated mice. Male mice castrated at day 0 after birth were pretreated with daily injections of testosterone propionate (TP, 100 micrograms/mouse), 17 beta-estradiol (E2, 5 micrograms/mouse) or vehicle for 20 days starting from day 60; daily TP injections (100 micrograms/mouse) for 30 days were started again from day 110 in all the pretreated mice to examine androgen-induced proliferation by incorporation of 5-[125I]iodo-2'-deoxyuridine into the whole seminal vesicles. Both TP and E2 pretreatments significantly increased the seminal vesicle weight found before TP treatment. However, androgen-induced proliferation of the seminal vesicle found in neonatally castrated mice (poor response; long duration with a low peak on day 3) was changed at least in part to that found in mice castrated at adulthood (good response; short duration with a high peak on day 3) only following the TP pretreatment but not at all following the E2 pretreatment. The E2 pretreatment induced poor androgen-induced proliferation with a low peak on day 7.  相似文献   
68.
Sachiko Tamura 《Hydrobiologia》1986,132(1):243-249
An analysis of the karyotypes of Dugesia japonica japonica Ichikawa et Kawakatsu, 1964, from 30 localities of seven river systems in Ôsaka Prefecture, Central Japan, revealed a total of 26 karyotypes of which 12 are new-found varieties. More than two karyotypes were found in many localities. The mixoaneuploidic triploid karyotype showed the widest distribution (21 localities), orthoploidic diploid karyotype and orthoploidic mixoploid of diploid and triploid karyotype were next (13 localities, respectively), and other karyotypes (triploidic aneuploid, orthoploidic triploid and mixoploid of triploid & tetraploid) were also found. Some correlation of karyotype with elevation was also detected.  相似文献   
69.
In vitro stimulation of human lymphocytes were studied in connection with cell fusion. When splenic lymphocytes were stimulated with human cytomegalovirus (CMV), they produced IgG but not IgM antibody against CMV. The stimulation with 50 ng/ml of CMV antigen induced the maximum antibody response, and higher concentrations of CMV antigen decreased antibody response and increased nonspecific IgG production. Human splenic lymphocytes were stimulated for 6 days with CMV antigen (50 ng/ml) and/or B-cell growth factor (BCGF), and then fused with mouse myeloma cells. Stimulation with a combination of antigen and BCGF were able to generate CMV-specific hybridomas synergistically. Two of these hybridomas were cloned by limiting dilution. The human monoclonal antibodies produced by them, C1 and C23, bound to CMV but not to other herpesviruses. C23 neutralized virus infectivity C1 did not at all. This method for generation of hybridomas producing human monoclonal antibodies against a predefined antigen may be applicable to a variety of viral antigens.  相似文献   
70.
Proliferation and death of androgen- and estrogen-responsive cells in seminal vesicles were compared between neonatally and adult (on Day 60 after birth) castrated mice. Daily injections of either testosterone propionate (TP) or estradiol-17 beta (E2) were started on Day 90 after birth; the incorporation of 5-[125I]iodo-2'-deoxyuridine ([125I]IdUrd) into the whole seminal vesicles was used as an index for proliferation. Although the peak of [125I]IdUrd uptake was observed 3 days after starting TP injections in both neonatally and adult castrated mice, the peak was lower and the period of proliferation was much longer in the former than in the latter. When TP injections were stopped, the fraction of surviving cells that synthesized DNA on Day 3 of TP injections was much larger in neonatally than adult castrated mice. The difference was attributed to the presence of TP-induced proliferation of fibromuscular cells in the neonatally castrated mice but not in the adult castrated mice; only the fibromuscular cells but not epithelial cells survived after stopping TP injections. Although injections of E2 increased the proliferation of epithelial cells but did not the weight of seminal vesicles in adult castrated mice, the same procedure increased the proliferation of both epithelial and fibromuscular cells and the weight in neonatally castrated mice. The E2-induced fibromuscular cells seemed to survive in the presence or absence of E2. The present results seem to indicate that androgen- and estrogen-induced proliferation of fibromuscular cells is irreversible in seminal vesicles of neonatally castrated mice and that the depletion of androgen in the seminal vesicle during neonatal and prepubertal periods is at least in part compensated by the administration of androgen, even after 90 days of age.  相似文献   
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