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21.
Decreased blood perfusion in canine tibial diaphysis after filling with acrylic bone cement compared with inert bone wax 总被引:1,自引:0,他引:1
Sixteen dogs had one tibia filled with acrylic PMMA bone cement and the opposite, control tibia filled with inert bone wax. After 1, 4, and 12 weeks, the blood perfusion in diaphyses was measured with Sc-46 labeled microspheres. The blood flow rates increased from 1 to 4 weeks and dropped to about the 1-week level after 12 weeks on both sides, with the acrylic side lower than the control side. On both sides, Disulphine Blue staining of the bones showed severe endosteal avascularity after 1 and 4 weeks and massive periosteal apposition after 4 and 12 weeks. The initial increase in blood flow is considered due to periosteal apposition, and the differences in blood flow rates are attributed to avascularity caused by the polymerization heat and toxicity of the acrylic cement. 相似文献
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K. Brocks J. S.Jensen J. F. Schmidt B. Chræmmer Jørgensen 《Acta anaesthesiologica Scandinavica》1987,31(5):448-449
Forty women, aged 26-40 years, were investigated with regard to gastric contents and pH before general anaesthesia. The patients were divided into two groups (20 in each). Group 100 received 0.3 mg kg-1 diazepam orally with 100 ml of water 2 h before surgery. Group 50 received 0.3 mg kg-1 diazepam with 50 ml of water 2 h before surgery. The amount of gastric content was significantly greater in Group 100 than in Group 50 (P less than 0.05). There was no statistical difference in pH values between the groups. The number of patients with both gastric pH less than 2.5 and gastric volume greater than 25 ml was significantly higher in Group 100 compared to Group 50 (P less than 0.05). We cannot recommend the use of oral premedication using these amounts of water, considering the increased risk of aspiration of gastric contents. 相似文献
24.
D. M. Jensen P. Damm B. Sørensen L. Mølsted-Pedersen J. G. Westergaard L. Korsholm P. Ovesen H. Beck-Nielsen 《Diabetic medicine》2003,20(1):51-57
AIMS: To study if established diagnostic threshold values for gestational diabetes based on a 75-g, 2-h oral glucose tolerance test can be supported by maternal and perinatal outcomes. METHODS: Historical cohort study of 3260 pregnant women examined for gestational diabetes on the basis of risk indicators. Information on oral glucose tolerance test results and clinical outcomes were collected from medical records. RESULTS: There was an increased risk of delivering a macrosomic infant in women with 2-h capillary blood glucose of 7.8-8.9 mmol/l compared with women with 2-h glucose < 7.8 mmol/l. Despite treatment, 2-h glucose of 9.0-11.0 mmol/l and > or = 11.1 mmol/l were both associated with increased rates of macrosomia, spontaneous preterm delivery, hypertensive complications, and neonatal hypoglycaemia. Adverse outcomes tended to be more frequent in women with 2-h glucose > or = 11.1 mmol/l than in women with 2-h glucose of 9.0-11.0 mmol/l. CONCLUSIONS: The risk for several maternal and perinatal complications increased with the diagnostic threshold for 2-h glucose. Large-scale blinded studies are needed to clarify the question of a clinically meaningful diagnosis of gestational diabetes mellitus. Until these results are available, a 2-h threshold level of 9.0 mmol/l after a 75-g oral glucose tolerance test seems acceptable. 相似文献
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Jean-Pierre Chanoine MD PhD Sarah Hampl MD FAAP Craig Jensen MD Mark Boldrin MS Jonathan Hauptman MD 李呈亿 《美国医学会杂志》2006,25(1):34-43
背景:儿童和青少年超重和肥胖正迅速增加。在该人群,单纯行为疗法减肥及维持体重下降的效果有限,但是对药物治疗尚未进行广泛的研究。
目的:确定奥利州他(Orlistat)在青少年体重治疗方面的效果及其安个性。
设计、地点和病例:于美国和加拿大32个中心、539例肥胖青少年(12—16岁;体重指数[body mass index,BMI]在第95百分化之上≥2单位)进行的多ln0、54剧(2000年8月至2002年10月)随机双盲研究。
干预:给予奥利司他(n=357)或安慰剂(n=182)120mg,每口3次,持续1年;加适度低热卡饮食(脂肪占30%)、运动和行为治疗。
主要观察指标:BMI变化;二级指标包括腰围和髋用、体重下降、脂质测量以及机体对口服葡萄糖的血糖和胰岛素反心。
结果:至12周时,两组BMI均有下降;此后,奥利司他组体重维持稳定而安慰剂组则超过基线。研究结束时,奥利司他组BMI下降0.55。而安慰剂组则增加0.31(P=0.001)。与安慰剂组的15.7%相比,奥利司他组26.5%的病例BMI下降≥5%(P=0.005);BMI下降≥10%者分别为4.5%和13.3%(P=0.002)。在研究结束时,奥利司他组体重增加0.53kg,安慰剂组增加3.14kg(P〈0.001)。双能X线吸收测量娃示,这种差异可用脂肪体再的变化解释。奥利司他组腰围下降,安慰剂组腰围上升(-1.33cm比+0.12cm;P〈0.05)。奥利司他组发生轻至中度胃肠道不良事件者为9%-50%,安慰剂组为1%~13%。
结论:与安慰剂比较,奥利司他与饮食、运动和行为改善联合可显著改善肥胖青少年体重的治疗。在这个青少年人群,连续使用奥利司他1年并无重要安全问题,尽管奥利司他组胃肠道不良事件较为常见。 相似文献
27.
richard G Fiscella Michael K Jensen 《American journal of health-system pharmacy》2003,60(5):484-5; author reply 485
28.
Four patients, who received epidural blood patch to treat postdural puncture headache, were examined with computed tomography in order to demonstrate the distribution of the injected blood. Blood alone could not be identified, but adding 2 ml contrast agent Iohexol 180 mg J/ ml (Omnipaque®, Nycomed Imaging) to 18 ml blood gave an excellent demonstration of the distribution of the blood in the epidural space, both cranio-caudally (7–14 segments) and spatially in relation to the epidural septae. The blood-contrast media had a strong affinity to the dural sac. There was no support of the spacefilling effect of blood patch. 相似文献
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Hazard assessment is a basic tool used in the evaluation and regulation of chemicals, but in spite of this there are many different interpretations of the scope and function of a hazard assessment. Starting from a discussion of the essential elements and conceptual frames involved, an attempt is made to identify the sources of uncertainty that are inherent in a hazard assessment. Problems identified include unambiguous identification of the chemical source, the routes of exposure, and the possible targets to be considered. Inadequacies in effects data are frequent, but unlike many of the other sources of uncertainty, these are often compensated for by the use of safety factors when setting quantitative limits for human or environmental exposure. The inherent uncertainties in the process make periodic revisions of any hazard assessment process inevitable, as new knowledge on routes of exposure and targets becomes available. 相似文献