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301.
This study reports the authors' 5-year experience with treating lower extremity injuries in bicycle passengers caused by the spokes. This patient group was selected from 716 lower extremity injuries that received treatment at our outpatient plastic surgery clinic. A total of 26 patients were treated during the study. Patients ranged from 2 to 19 years old, with a mean age of 5.6 years. The authors treated more female passengers (62 percent) than male passengers. The right foot (52 percent) was involved more often than was the left. Most patients were injured in the afternoon, from 2 to 7 PM (62 percent), and between May and October (77 percent). The rear wheel (89 percent) injured the majority of patients. The Achilles tendon was the most common site of injury (63 percent). The typical types of wounds observed included the following: type I, laceration with partial avulsion of skin and subcutaneous tissue (41 percent) and laceration forming a distally based flap (33 percent); type II, abrasions with ecchymoses and friction burn from the shearing effect of the spokes creating a partial- to full-thickness skin defect (26 percent). Of the type I injuries, full-thickness skin lacerations (33 percent) were closed primarily. Partial-thickness skin lacerations, abrasions, ecchymoses, and skin defects (67 percent) were treated conservatively with wound irrigation and dressing. The wound healing time for type I injuries was 29 days; for type II injuries, it was 27 days. These healing times were prolonged compared with healing by first intention. No significant difference was found in healing time when comparing both types of injury. Four patients required hospitalization. No patient required skin grafting. No fractures were noted because these patients were selected from the outpatient plastic surgery clinic and did not include patients from the emergency room. Since the first report of bicycle spoke injuries a half-century ago, prevention has not improved. 相似文献
302.
Shimada Y Nishimura M Kakinuma S Okumoto M Shiroishi T Clifton KH Wakana S 《Radiation research》2000,154(3):293-300
Although information on the molecular pathways in radiation carcinogenesis is accumulating, the data are still relatively scanty. To find the tumor suppressor locus associated with radiation carcinogenesis, we determined the frequency and distribution of loss of heterozygosity (LOH) of X-ray-induced thymic lymphomas of B6C3F(1) mice using 58 microsatellite markers and compared the results with those for spontaneous lymphomas and N-ethylnitrosourea (ENU)-induced lymphomas. Based on the results, we describe a unique locus with frequent LOH in the centromeric region of chromosome 11 of X-ray-induced lymphomas. This locus has never been observed to be altered similarly in either ENU-induced or spontaneous lymphomas, suggesting radiation-specific molecular alteration. The LOH patterns of individual thymic lymphomas indicated that the common region of LOH was located within 1.6 cM between D11Mit62 and D11Mit204, a region syntenic to human chromosome 7p13. Linkage analysis revealed that the markers of the common LOH region were genetically linked to Ikaros (now known as Znfn1a1), a master gene of lymphopoiesis. Although the presence of radiation-associated LOH in other loci cannot be ruled out, these results suggest a novel molecular pathway in induction of thymic lymphomas by ionizing radiation. 相似文献
303.
Kono M Tsuda T Ogata S Takashima S Liu H Hamamoto T Itzkowitz SH Nishimura S Tsuji S 《Biochemical and biophysical research communications》2000,272(1):94-97
The acceptor substrate specificities of ST6GalNAc I and II, which act on the synthesis of O-linked oligosaccharides, were reexamined using ovine submaxillary mucin, [Ala-Thr(GalNAc)-Ala]n polymer (n = 7-11). It has been suggested that only ST6GalNAc I can synthesize carbohydrate structures of sialyl-Tn-antigen; i.e., NeuAc alpha2-6GalNAc-O-Thr/Ser [Kurosawa et al., J. Biol. Chem. 269, 19048-19053 (1994)] based on the result that ST6GalNAc I, not ST6GalNAc II, exhibited activity toward asialoagalacto-fetuin. In this study, we present evidence that both ST6GalNAc I and II exhibit activity toward asialo-OSM (ovine submaxillary mucin) and [Ala-Thr(GalNAc)-Ala]n polymer (n = 7-11) which have only the GalNAc-O-Thr/Ser-structures. These results strongly indicate that not only ST6GalNAc I but also II are candidates for sialyl-Tn synthases. 相似文献
304.
305.
Short- and long-term clinical outcomes in rhesus monkeys inoculated with a highly pathogenic chimeric simian/human immunodeficiency virus 总被引:6,自引:0,他引:6
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Endo Y Igarashi T Nishimura Y Buckler C Buckler-White A Plishka R Dimitrov DS Martin MA 《Journal of virology》2000,74(15):6935-6945
A highly pathogenic simian/human immunodeficiency virus (SHIV), SHIV(DH12R), isolated from a rhesus macaque that had been treated with anti-human CD8 monoclonal antibody at the time of primary infection with the nonpathogenic, molecularly cloned SHIV(DH12), induced marked and rapid CD4(+) T cell loss in all rhesus macaques intravenously inoculated with 1.0 50% tissue culture infective dose (TCID(50)) to 4.1 x 10(5) TCID(50)s of virus. Animals inoculated with 650 TCID(50)s of SHIV(DH12R) or more experienced irreversible CD4(+) T lymphocyte depletion and developed clinical disease requiring euthanasia between weeks 12 and 23 postinfection. In contrast, the CD4(+) T-cell numbers in four of five monkeys receiving 25 TCID(50)s of SHIV(DH12R) or less stabilized at low levels, and these surviving animals produced antibodies capable of neutralizing SHIV(DH12R). In the fifth monkey, no recovery from the CD4(+) T cell decline occurred, and the animal had to be euthanized. Viral RNA levels, subsequent to the initial peak of infection but not at peak viremia, correlated with the virus inoculum size and the eventual clinical course. Both initial infection rate constants, k, and decay constants, d, were determined, but only the latter were statistically correlated to clinical outcome. The attenuating effects of reduced inoculum size were also observed when virus was inoculated by the mucosal route. Because the uncloned SHIV(DH12R) stock possessed the genetic properties of a lentivirus quasispecies, we were able to assess the evolution of the input virus swarm in animals surviving the acute infection by monitoring the emergence of neutralization escape viral variants. 相似文献
306.
Involvement of protein tyrosine phosphorylation in the effect of green tea polyphenols on Ehrlich ascites tumor cells in vitro 总被引:2,自引:0,他引:2
David Opare Kennedy Satomi Nishimura Tadayoshi Hasuma Yoshihisa Yano Shuzo Otani Isao Matsui-Yuasa 《Chemico-biological interactions》1998,110(3):645-172
Green tea extract and its polyphenolic components have been found to possess anticarcinogenic, antimutagenic, antihypertensive and antihepatotoxic effects, and several mechanisms have been proposed for these effects. In this study, the effects of five tea polyphenols, (−)-epigallocatechin-3-gallate (EGCG), (−)-epigallocatechin (EGC), (−) epicatechin-3-gallate (ECG), (−) epicatechin (EC) and (+)-catechin (C), were examined on the viability of Ehrlich ascites tumor cells in vitro and a possible relationship with tyrosine phosphorylation was determined. Proteins extracted from the cells treated with the tea polyphenols were separated by SDS-PAGE, and tyrosine-phosphorylated proteins were detected by immunoblotting with anti-phosphotyrosine antibody and the extent of phosphorylation determined. EGC (100 μM) caused a significant decrease in cell viability to 4.1±0.2% of the control value, and this correlated with a stimulation of protein tyrosine kinase (PTK) activity. EGCG (100 μM) also caused a slight decrease in cell viability (70% of the control value) but this and the other polyphenols, which had no effect on cell viability likewise, had no effect on tyrosine phosphorylation. Tyrosine phosphorylations of 42 and 45 kDa proteins were also observed for EGC. Further evaluation of the effect of EGC showed that the activity of ornithine decarboxylase (ODC), a key enzyme in polyamine biosynthesis in cells, decreased significantly as well. A significant correlation has therefore been observed between a cellular event, namely, a reduction in the viability of Ehrlich ascites tumor cells and an association with a tyrosine phosphorylation of 42 and 45 kDa proteins by the polyphenol EGC. 相似文献
307.
Measurement of early pregnancy factor activity for monitoring the viability of the equine embryo 总被引:4,自引:0,他引:4
Takagi M Nishimura K Oguri N Ohnuma K Ito K Takahashi J Yasuda Y Miyazawa K Sato K 《Theriogenology》1998,50(2):255-262
The viability of embryos before flushing from donor mares (n = 5) and after transfer to recipient mares (n = 7) was monitored in mare serum by detecting early pregnancy factor (EPF) using the rosette inhibition test (RIT). The EPF activity was measured in donor mares before and after natural mating at natural estrus; after ovulation on Days 2, 5 and 8; and after embryo flushing (Day 8) on Days 8, 9, 10 and 13 after ovulation. The collected embryos were transferred immediately after flushing. The EPF activity in recipient mares were measured on the day of transfer and after embryo transfer on Days 1, 2, 3 and 5. Pregnancy was confirmed on Day 12 to 14 after embryo transfer. The mean EPF activity of donor mares was increased to the pregnant level (> an RI titer score of 10) on Day 2 after ovulation. Two days after flushing the embryos, the EPF activity of donor mares had decreased to the nonpregnant level. Among the 7 recipient mares, 3 mares were diagnosed pregnant on Day 12 after embryo transfer with ultrasound. The EPF activity of the pregnant recipient mares was increased above the minimum level observed in pregnant mares on Days 2 to 3 after transfer. However, among the nonpregnant recipient mares after embryo transfer, the EPF activity of 3 mares remained at the pregnant level only 2 to 3 d and then declined to the nonpregnant level. In one recipient mare, EPF activity did not reach the pregnant level throughout the sample collection. The results of this study indicated that equine EPF can be detected in serum of pregnant mares as early as Day 2 after ovulation. From our observation, we conclude that the measurement of EPF activity is useful for monitoring the in vivo viability of equine embryos and early detection of embryonic death. 相似文献
308.
Measurement of intracellular Ca2+ concentration ([Ca2+]i) has been a fundamental technique in cell biology. However, most investigations have used cultured or isolated cells as an experimental model, and consequently can provide only limited insight into the mechanisms that operate in tissue in situ. Useful information may be obtained by studying intact tissue specimens. High-speed confocal microscopes that can acquire digital images at video rate have recently been developed. These confocal microscopes which can acquire data in real-time enable [Ca2+]i dynamics of individual cells in intact tissue specimens to be observed. The present paper examines the use of fluorescent microscopy and confocal microscopy for [Ca2+]i imaging of living tissue. We analyzed the dynamics of the duodenal gland, lacrimal gland, intestinal smooth muscles, arterioles, myenteric plexus, and dorsal root ganglion. In these specimens, individual cells exhibited different [Ca2+]i dynamics, and the responses to transmitters/modulators were heterogeneous. In conclusion, real-time imaging provides a useful tool for observing dynamic changes in cells in situ, and it may lead to improve understanding tissue physiology. 相似文献
309.
Masayuki Mori Shingo Akiyoshi Yosuke Mizuno Hisato Okuizumi Yasushi Okazaki Yoshihide Hayashizaki Masahiko Nishimura 《Mammalian genome》1998,9(9):695-709
We have applied the restriction landmark genomic scanning (RLGS) method to the SMXA recombinant inbred (RI) mouse strain
set to reveal its detailed genetic profile. A total of 663 polymorphic RLGS spot loci were identified, 576 of which were assigned
to chromosomes. Strain distribution patterns (SDPs) at 55 microsatellite marker loci were also obtained. As a result, the
total number of loci with distinct SDPs on chromosomes increased to 400. These loci were dispersed on all chromosomes, except
for the Chromosome (Chr) Y, and effectively covered the genome with an average spacing of 4 cM. The SMXA RI strain set, hereby,
would be of value for genetic study.
Received: 20 February 1998 / Accepted: 19 May 1998 相似文献
310.
Transport of storage proteins to protein storage vacuoles is mediated by large precursor-accumulating vesicles 总被引:17,自引:3,他引:14
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Novel vesicles that accumulate large amounts of proprotein precursors of storage proteins were purified from maturing pumpkin seeds. These vesicles were designated precursor-accumulating (PAC) vesicles and had diameters of 200 to 400 nm. They contained an electron-dense core of storage proteins surrounded by an electron-translucent layer, and some vesicles also contained small vesicle-like structures. Immunocytochemical analysis revealed numerous electron-dense aggregates of storage proteins within the endoplasmic reticulum. It is likely that these aggregates develop into the electron-dense cores of the PAC vesicles and then leave the endoplasmic reticulum. Immunocytochemical analysis also showed that complex glycans are associated with the peripheral region of PAC vesicles but not the electron-dense cores, indicating that Golgi-derived glycoproteins are incorporated into the PAC vesicles. These results suggest that the unique PAC vesicles might mediate a transport pathway for insoluble aggregates of storage proteins directly to protein storage vacuoles. 相似文献