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Y Ito Y Iguchi T Kashiwagi Y Imanishi 《Journal of biomedical materials research》1991,25(11):1347-1361
Synthesis of nonthrombogenic materials without using biologically active substances was explored. Poly(sodium vinyl sulfonate) is a water-soluble synthetic polymer and activates antithrombin III to exert nonthrombogenicity that was dependent on the molecular weight. Polyetherurethaneurea film was plasma-treated and graft-polymerized with sodium vinyl sulfonate. The graft film showed excellent in vitro and ex vivo nonthrombogenicity by suppressing interactions with plasma proteins and platelets as well as by inactivating blood-clotting factors. 相似文献
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Shinichi Miyagawa David L. Buchanan Tomomi Sato Yasuhiko Ohta Yukio Nishina Taisen Iguchi 《Anatomical record (Hoboken, N.J. : 2007)》2002,266(1):43-50
The urethral duct and vagina are formed from the urogenital sinus (UGS) during the early neonatal period in mice. Neonatal estrogen exposure results in hypospadias, or the malpositioning of vaginal and urethral openings, with wide cleft clitoris. We sought to characterize diethylstilbestrol (DES) influence on UGS morphogenesis and hypospadias formation. Newborn (day 0) and 1–4‐day‐old female mice (ICR/Jcl) were given (s.c.) oil or 3.0 μg DES. Animals were killed 24 hr later; then hypospadias formation and epithelial apoptosis and proliferation within the developing UGS were assessed. DES did not alter normal UGS morphogenesis by day 1, in comparison with controls. However, hypospadias formation was observed in DES‐treated mice by day 3. In these mice, the distal dorsal urethral duct appeared to fuse with and open into the lower vaginal solid cord region. Further, DES treatment produced a gradual significant increase in dorsal urethral epithelial apoptosis (P < 0.05) just prior to and during fusion and hypospadias formation. DES‐induced urethral epithelial and sinus cord proliferation appeared significantly increased (P < 0.05) and unchanged, respectively, just prior to fusion. By day 5, DES‐treated mice exhibited wide cleft clitoris. In addition, if DES was given on day 3 or 5, a gradual, distinct caudal shift in the vaginal‐urethral junction was observed compared to mice treated on days 0–2. Although hypospadias was not induced when neonates were given DES on day 7, these mice continued to display early vaginal opening. Dose‐response analysis indicated that 0.03 μg DES for 5 days is the lowest known critical dose for hypospadias induction. We have shown for the first time that DES‐induced hypospadias onset may primarily be the result of changes in developing dorsal urethral epithelial cell apoptotic and proliferative activity, and that the location of DES‐induced hypospadias formation is dependent on age at time of exposure. Anat Rec 266:43–50, 2002. © 2002 Wiley‐Liss, Inc. 相似文献
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Yoshimoto M Chang H Shiota M Kobayashi H Umeda K Kawakami A Heike T Nakahata T 《Stem cells (Dayton, Ohio)》2005,23(5):610-618
Recent studies have indicated that bone marrow cells can regenerate damaged muscles and that they can adopt phenotypes of other cells by cell fusion. Our direct visualization system gave evidence of massive muscle regeneration by green fluorescent protein (GFP)-labeled CD45+c-Kit+Sca-1+Lin- cells (KSL cells), and we investigated the role of KSL cells in muscle regeneration after transplantation with or without lethal irradiation. In the early phase, GFP signals were clearly observed in all the muscles of only irradiated mice. Transverse cryostat sections showed GFP+myosin+ muscle fibers, along with numerous GFP+ hematopoietic cells in damaged muscle. These phenomena were temporary, and GFP signals had dramatically reduced 30 days after transplantation. After 6 months, GFP+ fibers could hardly be detected, but GFP+c-Met+ mononuclear cells were located beneath the basal lamina where satellite cells usually exist in both conditioned mice. Immunostaining of isolated single fibers revealed GFP+PAX7+, GFP+MyoD+, and GFP+Myf5+ satellite-like cells on the fibers. Single-fiber cultures from these mice showed proliferation of GFP+ fibers. These results indicate two different roles of KSL cells: one leading to regeneration of damaged muscles in the early phase and the other to conversion into satellite cells in the late phase. 相似文献
15.
Effects of repeated subculturing and prolonged storage at room temperature of enterohemorrhagic Escherichia coli O157:H7 on pulsed-field gel electrophoresis profiles
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Iguchi A Osawa R Kawano J Shimizu A Terajima J Watanabe H 《Journal of clinical microbiology》2002,40(8):3079-3081
Three clinical strains of enterohemorrhagic Escherichia coli O157:H7 which were subcultured repeatedly or stored at room temperature over a 25-week period showed appreciable variations in their pulsed-field gel electrophoresis fragment patterns. The variations could be explained by a couple of spontaneous genetic events at most and thus did not invalidate the genetic lineage of the strains. 相似文献
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Polyovular follicles in the ovary of immature mice exposed prenatally to diethylstilbestrol 总被引:2,自引:0,他引:2
Summary Polyovular follicles (PF) occur in the ovary of 30-day-old offspring of ICR/JCL mice given 4 daily subcutaneous injections of 20–2,000 g diethylstilbestrol (DES)/day from days 15 to 18 of gestation. PF containing 2–9 oocytes per follicle in the prenatally DES-exposed mice are increased 33- to 112-fold as compared to controls. In 5- to 25-day-old offspring of mothers given injections of 2,000 g DES/day, PF are observed 17–65 times more frequent than in controls. 相似文献
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Recently large amounts of Aspergillus restrictus, a species of osmophilic fungi, have been detected in house dust using culture media with low water activity. But little attention has been paid to this fungus as an allergen. In the present study, the authors examined the allergenic activity of A. restrictus by skin prick tests and radioallergosorbent tests (RAST) on 94 asthmatic patients (mean age 12.0, range 3-18). Aspergillus fumigatus, Alternaria alternata and house dust were used for comparison. In the skin prick tests, A. restrictus, A. fumigatus, A. alternata and house dust elicited positive reactions in 8 (8.5%), 8 (8.5%), 15 (16.0%) and 69 (73.4%) patients, respectively. RAST showed positive reactions in 27 (28.7%) subjects for A. restrictus, 22 (23.4%) for A. fumigatus, 35 (37.2%) for A. alternata, and 75 (79.8%) for house dust. These results indicated that some asthmatic individuals showed immediate-type hypersensitivity to A. restrictus, and the prevalence of hypersensitivity of A. restrictus determined by skin prick tests and RAST was comparable with that of A. fumigatus but lower than that of A. alternata or house dust. This indicates that this fungal species may be of importance as a causative agent in atopic diseases. 相似文献
20.
Sex differences in the innominate bone of C57BL/Tw mice were studied morphometrically from the day of birth to 120 days of age. In neonatal male and female mice, a small cartilaginous spine was found on the basal part of ischium. This process disappeared in males within 24 hours after birth, whereas in females it remained until at least 30 days. Other sexual differences in the pubis and the ischium appeared at 30 and 120 days, respectively. The pubis in female mice was longer and thinner than that in the males, and the ischium in male mice was shorter and thicker than that in the females. Thirty-day-old female mice treated neonatally with testosterone or 5 alpha-dihydrotestosterone possessed pubic bones shorter and thicker than those of the age-matched untreated females. Pubes in male mice castrated at the day of birth were thinner than those in intact males. These findings suggest that the shape of the innominate bone is transformed to the male type under the influence of early postnatal androgen. 相似文献