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41.
Ji Young Kim Helen Shinn Young Jun Oh Yong Woo Hong Hyun Jeong Kwak Young Lan Kwak 《European journal of cardio-thoracic surgery》2006,29(3):343-347
OBJECTIVE: Redistribution hypothermia adversely affects hemodynamics and postoperative recovery in patients undergoing cardiac surgery. In off-pump coronary bypass surgery (OPCAB), maintaining the temperature is important because warming by cardiopulmonary bypass is omitted. Pre-warming studies reported earlier showing pre-warming as an effective means of preventing redistribution hypothermia was time consuming since it required at least 1-2h to pre-warm the patients before the surgery. Because pre-warming for such a long time is impractical in clinical practice, this study evaluated the efficacy of active warming during the preanesthetic period for the prevention of redistribution hypothermia in the early operative period of OPCAB. METHODS: After gaining the approval of Institutional Review Board and informed consent from the patients, 40 patients undergoing OPCAB were divided into control and pre-warming groups. The patients in control group (n=20) were managed with warm mattresses and cotton blankets, whereas patients in pre-warming group (n=20) were actively warmed with a forced-air warming device before the induction of anesthesia. Hemodynamic variables and temperature were recorded before anesthesia (Tpre) and at 30 min intervals after anesthesia for 90 min (T30, T60, and T90). RESULTS: Active warming duration was 49.7+/-9.9 min. There were no statistically significant differences in skin temperature, core temperature and hemodynamic variables between the two groups at preinduction period except for mean arterial pressure and central venous pressure. The core temperature at T30, T60, and T90 was statistically higher in pre-warming group than that in control group. Core temperature of six (30%) and seven patients (35%) in control group was reduced below 35 degrees C at T60 and T90, respectively, whereas core temperature of only one patient (5%) in pre-warming group was reduced below 35 degrees C at T90 (P=0.02). CONCLUSIONS: Active warming using forced air blanket before the induction of anesthesia reduced the incidence and degree of redistribution hypothermia in patients undergoing OPCAB. It is a simple method with reasonable cost, which does not delay the induction of anesthesia nor the surgery. 相似文献
42.
In this study, an animal model of multiple system organ failure (MSOF) in rabbits, engendered by feeding E. coli prior to severe hemorrhagic shock, was used for the purpose of investigating 1) the relationship between lipopolysaccharide (LPS) and MSOF, and 2) the effectiveness of Re-LPS antiserum in preventing MSOF. The results showed that endotoxemia occurred very early, and its degree correlated well with that of organ dysfunction. Re-LPS antiserum administration abated the toxic effects and lowered the incidence of MSOF. These results suggest that sequential analysis of circulating LPS levels may be useful for the early diagnosis of MSOF, and that gut-derived endotoxin might play an important role in the pathogenesis of experimental MSOF. 相似文献
43.
血管内皮生长因子与妊娠高血压综合征发病的关系 总被引:2,自引:0,他引:2
目的 探讨血管内皮生长因子 (VEGF)在妊娠高血压综合征发病中的作用。方法 分别采用酶联免疫吸附试验检测 40例妊高征孕妇的血清VEGF水平 ,免疫组化检测胎盘及蜕膜组织VEGF及CD3 4表达情况 ,35例正常孕妇作对照。结果 ①妊高征组孕妇的外周血VEGF水平及胎盘组织MVD明显低于正常妊娠组 (P <0 0 5 ) ;②两组胎盘绒毛滋养叶细胞和蜕膜组织中均有VEGF阳性表达 ,胎盘组织强阳性表达高于蜕膜。与对照组比较 ,其胎盘组织VEGF强阳性表达的轻度妊高征无显著性差异 ;而中度和重度妊高征与对照组相比 ,则明显降低 ,差异显著 (P <0 0 5 )。各组孕妇蜕膜组织中VEGF的表达强度和差异无显著性。③孕妇外周血VEGF水平与新生儿出生体重 (r =0 2 9,P <0 0 5 )和胎盘重量 (r =0 34,P <0 0 1)均存在直线正相关关系。结论 妊高征患者血清VEGF水平和胎盘组织MVD降低 ,胎盘组织VEGF表达明显下降 ,都可能在妊高征的发病中起一定的作用。 相似文献
44.
目的: 观察细胞内游离Ca2+([Ca2+]i)在培养的不同发育阶段皮层神经元无镁诱导惊厥性损伤中的作用,探讨惊厥性脑损伤年龄依赖性的可能机制.方法:体外培养6 d、17 d的胚胎大鼠皮层神经元用无镁细胞外液处理3 h,或于无镁处理前用NMDA(N-甲基-D-门冬氨酸)受体拮抗剂或Ca2+通道阻滞剂预处理,用MTT代谢率测定的方法检测神经元损伤,以Fluo-3作标记用激光共聚焦显微镜扫描的方法检测[Ca2+]i.结果:体外培养6 d、17 d的神经元单纯无镁组MTT代谢率较同期对照组降低.应用MK-801 10 μmol*L-1、AP-5 50 μmol*L-1、尼莫地平10 μmol*L-1预处理后再给无镁处理,培养6 d、17 d的神经元MTT代谢率均不同程度高于同期单纯无镁组.培养6 d、17 d的神经元相对荧光强度之间差异有显著性,两者与基线荧光强度比较差异亦有显著性.应用上述各种拮抗剂后,[Ca2+]i改变的峰值均明显低于同期单纯无镁组.结论: 在体外不同发育阶段的神经元,短暂无镁处理诱导惊厥样放电所引起的神经元线粒体功能损伤以及[Ca2+]i改变程度不同.这种[Ca2+]i改变的年龄依赖性可能是惊厥导致神经元损伤的年龄依赖性的机制之一.NMDA受体-Ca2+通道激活是导致这种[Ca2+]i改变及神经元损伤的关键环节. 相似文献
45.
目的:分析儿童呼吸道苛养菌的感染率及常用抗生素的耐药状况。方法:采用儿童呼吸道2050份咽拭子及痰标本进行苛养菌分离培养与鉴定,并对其中617株苛养菌做了药敏试验,结果:显示275株肺炎链球菌,耐药率较高的有红霉素81.1%,苯唑西林76.9%,复方磺胺甲恶唑76.9%,四环素65.4%;104株流感嗜血杆菌、184株副流感嗜血杆菌、54株卡他莫拉菌对氨苄西林耐药率分别为17.6%,28.9%,64.9%,对亚胺培南/西司他丁耐药率分别为16.4%,16.5%,0,同时复方磺胺甲恶唑的耐药率也分别高达56.7%,56.7%,64.9%。结论:提示苛养菌在儿童呼吸道感染中占有重要的地位,及时掌握这类细菌的耐药动态,对合理使用抗生素,延缓耐药株的产生有极其重要的临床意义。 相似文献
46.
Min Zhang Wen-Bin Li Jin-Xia Geng Qing-Jun Li Xiao-Cai Sun Xiao-Hui Xian Jie Qi Shu-Qin Li 《Journal of cerebral blood flow and metabolism》2007,27(7):1352-1368
Glial glutamate transporter-1 (GLT-1) plays an essential role in removing glutamate from the extracellular space and maintaining the glutamate below neurotoxic level in the brain. To explore whether GLT-1 plays a role in the acquisition of brain ischemic tolerance (BIT) induced by cerebral ischemic preconditioning (CIP), the present study was undertaken to observe in vivo changes in the expression of GLT-1 and glial fibrillary acidic protein (GFAP) in the CA1 hippocampus during the induction of BIT, and the effect of dihydrokainate (DHK), an inhibitor of GLT-1, on the acquisition of BIT in rats. Immunohistochemistry for GFAP showed that the processes of astrocytes were prolonged after a CIP 2 days before the lethal ischemic insult, which could protect pyramidal neurons in the CA1 hippocampus against delayed neuronal death induced normally by lethal ischemic insult. The prolonged processes extended into the area between the pyramidal neurons and tightly surrounded them. These changes made the pyramidal layer look like a 'shape grid'. Simultaneously, the prolonged and extended processes showed a great deal of GLT-1. Western blotting analysis showed significant upregulation of GLT-1 expression after the CIP, especially when it was administered 2 days before the subsequent lethal ischemic insult. Neuropathological evaluation by thionin staining showed that DHK dose-dependently blocked the protective role of CIP against delayed neuronal death induced normally by lethal brain ischemia. It might be concluded that the surrounding of pyramidal neurons by astrocytes and upregulation of GLT-1 induced by CIP played an important role in the acquisition of the BIT induced by CIP. 相似文献
47.
48.
口外弓配合唇档远移磨牙的临床研究 总被引:1,自引:1,他引:0
目的:研究口外弓配合唇档远移磨牙的临床应用及其疗效。方法:选择15例恒牙早期上颌轻度牙性前突或轻、中度拥挤的安氏II类患者,应用口外弓配合唇档,通过X线头影测量观察其上颌磨牙及前牙治疗前后变化情况。结果:应用口外弓配合唇档推磨牙向远中3~6个月后,II类咬合关系恢复至安氏I类关系。上颌第一磨牙向远中平均移动4.14mm,上颌中切牙向唇侧移动0.66mm。结论:只要病例选择合适,方法运用得当,口外弓配合唇档就能获得较满意的远移磨牙的疗效。 相似文献
49.
Douglas M. Howarth Martin T. Epstein Paul A. Thomas Leonard W. Allen Rachel Akerman Linda Lan 《European journal of nuclear medicine and molecular imaging》1997,24(12):1465-1469
The efficacy of fractionated out-patient radioiodine therapy in 38 patients with compressive symptoms due to long-standing
large multinodular goitres was assessed. The diagnosis was established by clinical assessment in addition to technetium-99m
pertechnetate thyroid scan or computed tomography scan of the thyroid and mediastinum. Oral iodine-131 therapy was administered
as a 2.22 GBq (60 mCi) cumulative dose over 4 months (555 MBq per month). All patients were monitored with serum thyroid-stimulating
hormone and free thyroxine (± free tri-iodothyronine) assays before the treatment and after each dose fraction. Clinical and
biochemical follow-up was performed on all patients and ranged from 6 to 45 months after therapy. The patients consisted of
35 female and three male patients with a median age of 59 years (range 37–87 years). Prior to treatment 20 patients were biochemically
hyperthyroid and 18 were euthyroid. Overall, 71% of patients reported a subjective improvement in compressive symptoms and
29% reported no change. Clinically assessed reduction in goitre size occurred in 92% of patients while there was no change
in 8%. At 3 months of follow-up, 31% of patients had become hypothyroid and at 18 months 66% were hypothyroid. Seven hyperthyroid
patients (35%) became euthyroid and 13 hyperthyroid patients (65%) became hypothyroid. Three patients who became hypothyroid
experienced neck soreness (transient in one patient, persistent in two patients). There were no differences in outcome between
patients who were hyperthyroid and those who were euthyroid prior to treatment. Fractionated out-patient radioiodine therapy
showed excellent short- and medium-term safety, was very well tolerated and offered a satisfactory alternative treatment to
surgery.
Received 23 May and in revised form 11 August 1997 相似文献
50.