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11.
Postoperative changes in vaginal smears after vaginal reconstruction with a free skin graft 总被引:1,自引:0,他引:1
Surgical vaginal reconstruction was performed by a free skin graft in two patients without a vagina. The postoperative changes in vaginal smears collected from the artificial vaginas were observed for about two years. Marked operation-induced inflammatory changes were observed until the second postoperative month. After the third postoperative month, the background became relatively clear. Cyanophilic and eosinophilic superficial cells, intermediate cells and D?derlein bacilli were observed occasionally in addition to keratotic cells. Six to 12 months after surgery, the vaginal smears showed little abnormality, except for the presence of keratotic cells. The changes in the vaginal smears after the third month show that the artificial vaginal epithelium changed cytologically to an almost normal vaginal mucosa that, although not histologically complete, responded to hormones. The presence of D?derlein bacilli suggests that the regional environment of the artificial vagina was almost the same as that of the normal vagina. 相似文献
12.
Influence of human recombinant interleukin-1 (hrIL-1) on collagen metabolism was investigated with rabbit uterine cervical fibroblasts. Enzyme-linked immunosorbent assays for collagenase and tissue inhibitor of metalloproteinases (TIMP) indicated that hrIL-1 participates in both stimulation of procollagenase production and suppression of TIMP synthesis by uterine cervical cells. IL-1 did not modulate collagen synthesis. In addition, the sensitivity to IL-1 of uterine cervix from ovariectomized rabbits was augmented by estradiol-17 beta treatment. Thus it is proposed that IL-1 accelerates collagenolysis in the cervical tissue and its effect on uterine cervix is hormonally regulated. 相似文献
13.
Purification and characterization of thylakoid-bound Mn-superoxide dismutase in spinach chloroplasts 总被引:5,自引:0,他引:5
Thylakoid-bound superoxide dismutase (SOD; EC 1.15.1.1) was solubilized by Triton X-100 from spinach and purified to a homogeneous state. The molecular weight of thylakoid-bound SOD was 52000; the enzyme was composed of two equal subunits. Its activity was not sensitive to cyanide and hydrogen peroxide, and the isolated SOD contained Mn, but neither Fe nor Cu. Thus, the thylakoid-bound SOD is a Mn-containing enzyme. The subunit molecular weight of thylakoid Mn-SOD is the highest among Mn-SODs isolated so far, a fact which might reflect its binding to the membranes. 相似文献
14.
A structural locus (C-6) for the sixth component of complement in mice is assigned to chromosome 15. Three-point linkage analysis indicated that the order of loci is C-6, Gpt-1, Gdc-1, and that the map distances are 25.9±4.9 between C-6 and Gpt-1, and 36.4±5.5 between C-6 and Gdc-1. Since Gdc-1 is more distal than Gpt-1, and C-6 is 26 cM away from Gpt-1, it is estimated that the C-6 is proximal to the centromere. In addition, a new C6 form found in AKR mice is described. We propose the designation C6B for it and C-6
b
for the allele encoding C6B.Abbreviations used in this paper IEF
isoelectric focusing
- GPT
glutamic-pyruvic transaminase
- GDC
L-glycerol 3-phosphate dehydrogenase
- cM
centimorgan 相似文献
15.
Various metals have been shown to inhibit porcine brain lipoamidase activity at 0.1 mM, but not ferrous and ferric ions. However, in the presence of ethylenediamine tetraacetic acid (EDTA) 0.1 mM iron ions did inhibit the activity. No other metals exhibited this type of increased inhibition with the addition of EDTA. The ferric- and ferrous-EDTA compounds were equally effective. Various Fe-containing compounds also inhibited the enzyme activity, the order of inhibition being: EDTA greater than o-phenanthroline greater than azide greater than citrate. Hemin also inhibited the enzyme activity strongly. However, Fe-proteins, e.g. cytochrome c, transferrin and peroxidases, were not inhibitory. These results indicate the importance of Fe ion chelates with structural and molecular size differences for interaction with the reaction center of this enzyme. 相似文献
16.
Juvenile hormone esterase activity repressive factor in the plasma of parasitized insect larvae 总被引:1,自引:0,他引:1
Y Hayakawa 《The Journal of biological chemistry》1990,265(19):10813-10816
A proteinaceous factor that represses plasma juvenile hormone esterase activity in parasitized insect larvae has been isolated and partially characterized from last instar larvae of the armyworm Pseudaletia separata parasitized with the wasp Apantales kariyai. Purification procedures consisted of extraction with 25% ethanol, gel filtration and reversed phase high performance liquid chromatography. Plasma juvenile hormone esterase activity in Day 3 last instar larvae was repressed by 50% when larvae were injected on Days 1 and 2 with 6.5 pmol of the purified peptide, which has a molecular weight of about 4,500 Da. The application of the factor also causes more than a 2-day delay in the onset of pupation. The sequence of 23 amino acid residues at the amino terminus of the factor was determined as follows: H-Glu-Asn-Phe-Ser-Gly-Gly-Xaa-Val-Ala-Gly-Tyr-Met- Arg-Thr-Pro-Asp-Gly-Arg-Xaa-Lys-Pro-Thr-Phe-Tyr-Gln-. 相似文献
17.
Formation of free radicals in golden hamster embryo (GHE) cells in the frozen living state by gamma irradiation has been studied by electron spin resonance spectroscopy at 4.2 and 77 K. The relative yields of H atoms, OH radicals, and organic radicals trapped in the irradiated GHE cells are 12, 72, and 16%, respectively, of total radical yields. When dimethylsulfoxide (DMSO) is added to GHE cells at 77 K, a large quantity of CH2SOCH3 radicals (DMSO radicals) are formed after gamma irradiation. The yields of OH radicals are not affected by the addition of DMSO. When the GHE cell-DMSO mixtures are irradiated with gamma rays at 77 K and then warmed to 111 K, the OH radicals decay, whereas the DMSO radicals do not increase complementarily. Moreover, the decay rates of the OH radicals at 111 K do not depend upon the concentration of DMSO. Thus OH radicals do not react with DMSO during warming of the irradiated sample. When H atoms are produced by gamma irradiation of acid ice at 60 K, the decay rates of the H atoms at 77 K increase with increasing DMSO concentration, indicating that DMSO reacts with H atoms (CH3SOCH3 + H----.CH2SOCH3 + H2) at 77 K by quantum-mechanical tunneling. When the GHE cell-DMSO mixture is irradiated with gamma rays at 77 or 4.2 K in the dark, DMSO ions are produced in addition to DMSO radicals. Therefore it is concluded that DMSO does not scavenge OH radicals, but does capture H atoms, holes and/or electrons in the gamma-irradiated cells, resulting in the remarkable formation of DMSO radicals. This scavenger effect of DMSO may be related to the radioprotection of DMSO against cell killing described in the companion paper (Watanabe et al., Radiat. Res., this issue). 相似文献
18.
E Suzuki Y Hirata H Matsuoka T Sugimoto H Hayakawa T Sugimoto K Kangawa N Minamino H Matsuo 《Biochemical and biophysical research communications》1992,182(3):1270-1276
To explore the mechanisms for the natriuretic effects of a neutral endopeptidase inhibitor, candoxatril, the concentration of atrial natriuretic peptide (ANP) and its molecular forms in the urine of Dahl salt-sensitive (S) rats were examined. Candoxatril-induced natriuresis (+120%, p less than 0.05) was associated with a marked increase in the urinary ANP excretion (+1200%, p less than 0.05). Analysis by Sephadex G-50 gel filtration revealed that molecular weight of the major fraction of immunoreactive (ir-) ANP in the plasma of candoxatril-treated Dahl S rats was 3K, whereas that in the urine was 2.5 K. Further analysis by reverse phase high performance liquid chromatography showed that ir-ANP in the plasma of Dahl S rats was alpha-rANP (1-28), while that in the urine from rats treated with candoxatril was alpha-rANP (1-25). These results indicate that candoxatril inhibits the complete degradation of ANP in the kidney, thereby increasing the amount of biologically active ANP reaching the distal nephron and contributing to natriuresis. 相似文献
19.
Kenji Takeuchi Sayumi Shibamoto Makio Hayakawa Takamitsu Hori Keiji Miyazawa Naomi Kitamura Fumiaki Ito 《Experimental cell research》1996,223(2):420
Hepatocyte growth factor (HGF) stimulated cell migration of human gastric carcinoma cell lines MKN1, MKN7, and MKN28. Epidermal growth factor (EGF) also stimulated the cell migration of these three cell lines. In MKN7 cells, HGF-stimulated cell migration was rather reduced in the presence of EGF, whereas such an observation was not made with MKN1 and MKN28 cells. Therefore, we compared the effect of EGF on HGF-stimulated HGF receptor phosphorylation in these cell lines. HGF induced a rapid tyrosine phosphorylation of the HGF receptor in all these cell lines. In MKN7 cells, the increased phosphorylation was further enhanced by EGF, although EGF alone did not affect tyrosine phosphorylation of the HGF receptor. In MKN1 and MKN28 cells, EGF did not influence tyrosine phosphorylation of the HGF receptor, whether HGF was present or not. The data presented here suggest that EGF negatively modulates the cellular response to HGF by increasing tyrosine phosphorylation of the HGF receptor in certain types of epithelial cells, e.g., MKN7 cells. 相似文献
20.
Summary Transgenic cucumber (Cucumis sativus L.) plants were successfully obtained from hypocotyl explants inoculated with Agrobacterium tumefaciens, which harbored a binary vector plasmid with NOS-nptII, CaMV 35S-I-gus and CaMV 35S-hph genes. Acetosyringone enhanced the efficiency of transformation at the cut surface cells of hypocotyl explants during five days of co-cultivation. Transformed cells were more effectively selected using 20–30 mg/l hygromycin B than using 50–100 mg/l kanamycin. Shoot regeneration occurred within 4–6 wks, and 12 of 21 regenerated plantlets displayed strong GUS expression in the very young leaves. All of 8 GUS-positive R0 plants examined showed single or a few positive bands by Southern blot analysis. The expression of the CaMV 35S-I-gus gene was observed in various tissues and organs of R0 and R1 transgenic cucumber plants. 相似文献