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71.
73.
Yukitomo Ishi Ai Shimizu Emi Takakuwa Minako Sugiyama Michinari Okamoto Hiroaki Motegi Shinsuke Hirabayashi Yuko Cho Akihiro Iguchi Atsushi Manabe Sumihito Nobusawa Shinya Tanaka Shigeru Yamaguchi 《Pathology international》2021,71(5):348-354
A 5-year-old girl presented with headache and vomiting. Head computed tomography and magnetic resonance imaging showed a right frontal lobe tumor with marked calcification. The patient underwent resection surgery with suspicion of anaplastic ependymoma, and the tumor was gross totally removed. Pathological examination revealed areas of dense tumor cells with a high nucleocytoplasmic ratio and myxoid areas consisting of tumor cells with a round-shaped nucleus and eosinophilic cytoplasm. Perivascular pseudorosette, necrosis, circumscribed growth, and microcalcification were also observed. Immunohistochemistry demonstrated negative staining for glial fibrillary protein and epithelial membrane antigen. Diagnosis of a high-grade neuroepithelial tumor (HGNET) with BCL6 corepressor (BCOR) alteration was made based on pathological findings and internal tandem duplication in the exon 15 of BCOR. Although calcification on radiological and pathological examination is not typical, it would be essential to recognize that calcification could appear in HGNET-BCOR. 相似文献
74.
Overcoming the organization–practice barrier in sports injury prevention: A nonhierarchical organizational model
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Ö. Dahlström J. Jacobsson T. Timpka 《Scandinavian journal of medicine & science in sports》2015,25(4):e414-e422
The organization of sports at the national level has seldom been included in scientific discussions of sports injury prevention. The aim of this study was to develop a model for organization of sports that supports prevention of overuse injuries. The quality function deployment technique was applied in seminars over a two‐season period to develop a national organizational structure for athletics in Sweden that facilitates prevention of overuse injuries. Three central features of the resulting model for organization of sports at the national level are (a) diminishment of the organizational hierarchy: participatory safety policy design is introduced through annual meetings where actors from different sectors of the sporting community discuss training, injury prevention, and sports safety policy; (b) introduction of a safety surveillance system: a ubiquitous system for routine collection of injury and illness data; and (c) an open forum for discussion of safety issues: maintenance of a safety forum for participants from different sectors of the sport. A nonhierarchical model for organization of sports at the national level – facilitated by modern information technology – adapted for the prevention of overuse injuries has been developed. Further research is warranted to evaluate the new organizational model in prospective effectiveness studies. 相似文献
75.
Hee Jin Park Sung Moon Lee So Yeon Lee Eun Seok Son Eun Chul Chung Myung Ho Rho Sun Joo Lee 《Korean journal of radiology》2015,16(6):1326-1331
ObjectiveWe described the technique of ultrasound (US)-guided percutaneous removal of the foreign bodies (FB) with hydro-dissection in the radiologic department and presented video files of several cases.ResultsThe mean time required for the entire procedure was approximately 20 minutes. There were no significant complications during the US-guided removal or long-term complications after the procedure. All 4 FBs were successfully removed from the soft tissue under US guidance.ConclusionUltrasound-guided percutaneous removal of the FBs with hydro-dissection in the radiology department is a less invasive and safe method over surgical removal in the operating room. Additionally, the use of a guide wire and serial dilator may help minimize soft tissue injury and facilitate the introduction of forceps. 相似文献
76.
C. Fanelli A. Di Vincenzo F. Modarelli M. Lepore M. Ciofetta L. Epifano S. Pampanelli P. Brunetti G. B. Bolli 《Diabetologia》1993,36(11):1191-1197
Summary It is controversial as to whether ketone bodies are utilized by the human brain as a fuel alternative to glucose during hypoglycaemia. To clarify the issue, we studied 10 normal volunteers during an experimental hypoglycaemia closely mimicking the clinical hypoglycaemia of patients with Type 1 (insulin-dependent) diabetes mellitus or insulinoma. Hypoglycaemia was induced by a continuous infusion of insulin (0.40 mU·kg–1·min–1 for 8 h, plasma insulin 180 pmol/l) which decreased the plasma glucose concentration to approximately 3.1 mmol/l during the last 3 h of the studies. Subjects were studied on two occasions, i. e. spontaneous, counterregulatory-induced post-hypoglycaemic increase in 3--hydroxybutyrate (from 0.2 to 1.1 mmol/l at 8 h), or prevention of post-hypoglycaemic hyperketonaemia (plasma -hydroxybutyrate 0.1 mmol/l throughout the study) after administration of acipimox, a potent inhibitor of lipolysis. In the latter study, glucose was infused to match the hypoglycaemia observed in the former study. The glycaemic thresholds and overall responses of counterregulatory hormones, symptoms (both autonomic and neuroglycopenic), and deterioration of cognitive function (psychomotor tests) were superimposable in the control study in which ketones increased spontaneously after onset of hypoglycaemic counterregulation, as compared to the study in which ketones were suppressed (p=NS). The fact that responses of counterregulatory hormones, symptoms and deterioration in cognitive function were not exaggerated when posthypoglycaemic hyperketonaemia was prevented, indicate that during hypoglycaemia, the counterregulatory-induced endogenous hyperketonaemia does not provide the human brain with an alternative substrate to glucose. Thus, it is concluded that during hypoglycaemia, endogenous hyperketonaemia does not contribute to brain metabolism and function. 相似文献
77.
Summary Subcutaneous injection of sodium dichloroacetate (1 mg/g body wt every 3 h) in suckling newborn rats caused in 6 h a fall
of 2.5 mmol/l in blood glucose concentrations, and a rise of 2.4 mmol/ l in total blood ketone body levels, but no change
in the high levels of plasma non esterified fatty acids. Glucose utilization, measured after intraperitoneal injection of
D-glucose (2 mg/g body wt), was not increased in newborns injected with dichloroacetate. The hypoglycaemia resulted from a
decrease in gluconeogenic rate, secondarily to a lowering effect of dichloroacetate on blood levels of lactate, pyruvate and
alanine. The hypoglycaemia induced by dichloroacetate was completely reversed by injecting newborn rats with a mixture of
gluconeogenic precursors (lactate, pyruvate and alanine). It is concluded that the high rate of gluconeogenesis observed in
suckling newborn rats in sustained by an increased release of lactate and, to a much smaller extent of pyruvate and alanine,
by peripheral tissues. This probably resulted from the low pyruvate dehydrogenase activity found in peripheral tissues of
the newborn rat. The hyperketonaemia induced by dichloroacetate could result from an increased ketogenesis and/or a decreased
ketone body utilization. 相似文献
78.
79.
Lei Wang Wei Cui Jean Pierre Kalal Tom Van Hoof Bao-Ge Liu 《Asian Pacific journal of tropical medicine》2014,(10)
Objective:To investigate the effect of osteoporosis and intervertebral disc degeneration on the endplate cartilage injury in rats.Methods:A total of 48 female Sprague Dawley rats(3 months)were randomly divided into Groups A,B,C and D with 12 rats in each group.Osteoporosis and intervertebral disc degeneration composite model,simple degeneration model and simple osteoporosis model were prepared in Groups A,B and C respectively.After modeling,four rats of each group at 12th.18th and 24th week were sacrificed,Intervertebral height of cervical vertebra C6/C7 was measured.Micro-CT was used to image the endplate of cephalic and caudal cartilage at C6/C7 intervertebral disc.Abraded area rate of C6 caudal and C7 cephalic cartilage endplate was calculated,and then C6/C7 intervertebral disc was routinely embedded and sectioned.stained with safranin O to observe histological changes microscopically.Results:At 12,18 and24 weeks,intervertebral disc height of C6/C7 were(0.58±0.09)mm,(0.53±0.04)mm and(0.04±0.06)mm in Group A rats,(0.55±0.05)mm,(0.52±0.07)mm and(0.07±0.05)mm in Group B rats.At 24th week.intervertebral disc height of Group A rats was significantly lower than that of Group B rats(P0.05);intervertebral disc height of Groups A and B rats at each time point were significantly lower than that of Groups C and D(P0.05).There was no significantly statistical difference of intervertebral disc height between Groups C and D(P0.05).At 12 and 18 weeks,the abraded rate of C6 caudal and C7 cephalic cartilage endplate in Group A rats were significantly higher than that in Groups B.C and D rats(P0.05);the abraded rate in Group B was significantly higher than that in Groups C and D(P0.05).Microscopic observation of CT showed that ventral defects in C6caudal or C7 cephalic cartilage endplate in Groups A and B appeared after 12 weeks of modeling;obvious cracks were found in front of the C6 and C7 vertebral body,and cartilage defect shown the trend of"repairing"at 18 and 24 weeks after modeling.Conclusions:Intervertebral disc degeneration and osteoporosis can cause damage to the cartilage endplate.Co-existence of these two factors can induce more serious damage to the endplate.which has possitive correlation with intervertebral disc degeneration.Osteoporosis plays a certain role in intervertebral disc degeneration process,and accelerates the degeneration of intervertebral disc in a specific time window. 相似文献
80.
目的:探讨口腔颌面部异物伤的诊断与治疗及影像学诊断的重要性。方法 :选择2003-01—2010-12期间收治的,影像和病历资料完善的口腔颌面部异物存留伤36例。分析异物类型,并对临床疗效进行评估。结果:36例异物存留伤患者中,金属异物12例,非金属异物24例。择期异物取出26例;需要急诊清创者10例,而清创术可一期取出异物者6例,4例延期取出。30例经常规X线片检查后,需经CT或三维CT检查进一步定位,评估手术取出的可行性及风险。其中26例经手术取出,4例保留并观察。结论:三维CT在非金属异物存留伤诊疗中起到重要的作用;必须根据异物大小、部位及与周围大血管的毗邻关系,患者全身情况等综合因素判定是否手术及手术时机。 相似文献