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81.
82.
【目的】 研究妊娠期接受磁共振 (magneticresonanceimaging ,MRI)复合磁场照射对子代大鼠不同发育期脑部丝裂原活化蛋白激酶 (mitogenactivatedproteinkinase ,MAPK) /细胞外信号调节蛋白激酶 (extracellularsignalregulatedproteinkinase ,ERK )表达的影响。  【方法】 SD孕鼠妊娠第 12~ 18d给予 0 .3 5TMRI磁场照射 ,雌性子鼠1、2、5月龄时进行大脑切片免疫组化SP方法染色 ,并用图像分析仪进行半定量分析。 【结果】 MAPK/ERK免疫反应在大鼠脑切片上广泛表达 ;随着年龄增长 ,未发现其表达的变化 ;在各年龄段子鼠照射组和对照组间MAPK/ERK的免疫反应表达差异均无显著性 (P >0 .0 5 )。 【结论】 妊娠期MRI磁场照射后并未引起子代大鼠MAPK/ERK免疫反应表达的异常  相似文献   
83.
Wu CC  Tai CL  Shih CH 《The Journal of trauma》2000,48(6):1063-1067
BACKGROUND: The aim of this study was to compare the superiority between the newly designed modified AO tension band wiring technique and the traditional modified AO tension band wiring technique in treating an olecranon fracture. METHODS: Eight pairs of fresh cadaveric ulnae were tested biomechanically. After transverse osteotomy of the olecranon, all left ulnae were fixed by the traditional modified AO technique with two Kirschner wires inserted through the anterior ulnar cortex and all right ulnae by the new technique with two Kirschner wires inserted into the marrow cavity from the olecranon to the ulnar styloid process. All specimens were tested by the Material Testing System machine to evaluate fragment displacement and the maximal failure load. A dual linear variable displacement transducer was used to measure relative minimal displacement. RESULTS: There was no significant difference between the techniques. The maximal failure load by either technique was more than 80 kg. Even at testing failure, no Kirschner wires migrated proximally. CONCLUSION: The new technique may be applied widely to treat all olecranon fractures, because it is a technically easier and safer technique. Less than 5.5-kg loads could be permitted in daily activity postoperatively. A single tolerable loading weight should not exceed 8 kg. Kirschner wires will not migrate proximally, despite increased joint loading. Clinically, this study may confirm indirectly the hypothesis that proximal migration of Kirschner wires was mainly due to triceps traction.  相似文献   
84.
OBJECTIVES: Ex vivo perfusion of the cardiac allograft during organ procurement is an ideal environment for adenoviral vectors with transgenes that target improving graft contractility. One such target is the beta-adrenergic receptor-signaling system, in which alterations in transgenic mice have elucidated novel means to improve the function of the heart in vivo. The purpose of the current study was to determine the functional consequences of beta-adrenergic receptor manipulation in a rabbit model of cardiac allograft transplantation. METHODS: New Zealand White rabbits weighing 3 kg served as recipients to 1-kg outbred donors. Donor hearts were arrested and harvested, and 1 of 3 adenoviral constructs was administered into the aortic root perfusing the graft. Transgenes delivered encoded either the human beta(2)-adrenergic receptor, a peptide inhibitor of beta-adrenergic receptor densensitization, or the marker transgene beta-galactosidase. RESULTS: Five days after cervical heterotopic transplantation, left ventricular performance was measured on a Langendorff apparatus. A moderate pattern of rejection was seen in all grafts. Biventricular myocyte expression of beta-galactosidase was observed, and beta(2)-adrenergic receptor density was elevated 10-fold in grafts that received adeno-beta(2)-adrenergic receptor. Left ventricular systolic and diastolic performance was significantly increased in grafts transfected with either adeno-beta(2)-adrenergic receptor or adeno-beta-adrenergic receptor densensitization compared with control grafts that received adeno-beta-galactosidase. CONCLUSIONS: Ex vivo adenovirus-mediated gene transfer is feasible in a rabbit allograft model and, more important, genetic manipulation of beta-adrenergic receptor signaling either by increasing beta(2)-adrenergic receptor density or blocking endogenous receptor desensitization improves graft function acutely in this allograft model.  相似文献   
85.
目的 比较接尘、吸烟对呼吸系统疾病死亡的影响.方法 在1989年至1992年广州建立职业健康监护档案的基础上对30岁以上、职业接触粉尘和无粉尘接触的80 987名工人进行前瞻性队列研究.结果 (1)队列平均年龄43.5岁,职业性粉尘接触率16.3%,吸烟率43.7%,饮酒率33.5%.(2)队列平均随访8年,35人失访,失访率0.04%,总死亡1 593人中,219人死于肺癌,90人死于非恶性肿瘤性呼吸系统疾病.(3)调整相关因素后,相对于不吸烟者,吸烟者肺癌死亡相对危险度(RR)为3.32,是粉尘接触者相对于无粉尘接触者肺癌死亡RR(1.53)的2.2倍.粉尘接触者非恶性肿瘤性呼吸系统疾病死亡RR为2.41,是吸烟者(1.89)的1.28倍.尤其是矽尘接触者,其非恶性肿瘤性呼吸系统疾病死亡RR为5.72,是吸烟者的3.03倍.既接触粉尘又吸烟,呼吸系统疾病死亡RR增加更明显.(4)男性吸烟者呼吸系统疾病死亡危险分别随日吸烟量、烟龄的增加而增加.结论 职业接触粉尘和吸烟均可引致超额的呼吸系统疾病死亡,两者存在协同作用.吸烟致肺癌死亡RR高于接尘,而致非恶性肿瘤性呼吸系统疾病死亡RR则低于接尘.吸烟与呼吸系统疾病死亡危险存在明显的剂量-效应关系.  相似文献   
86.
循证医学对现代儿科学的意义   总被引:2,自引:2,他引:2  
桂永浩教授:循证医学(evidence based medicine, EBM)是20世纪后期迅速发展起来的一门新兴的交叉学科。他之所以引起西方现代医学的高度重视是因为EBM 提出:医务人员在对患者进行的诊治中必须基于当前可得到的最佳的临床证据,并结合医生个人的经验和来自患者的临床资料,在充分尊重患者的选择和意愿的基础上,使患  相似文献   
87.
BACKGROUND/PURPOSE: Conventional training in bronchoscopy may increase patient's discomfort and procedure-related morbidity. Computer-based bronchoscopy simulator (CBBS) permits the acquisition and evaluation of the necessary skills through a realistic bronchoscopic experience. This study was conducted to validate the use of a CBBS system developed in Taiwan as a learning and assessment tool. METHODS: Twenty novice bronchoscopists and 10 expert bronchoscopists were enrolled as subjects in this prospective study. The 20 novice bronchoscopists were randomized into two groups, which received conventional bronchoscopic training or CBBS training and then completed a satisfaction survey. Subsequently, the novices who received CBBS training underwent an observational performance trial and the results were compared with those of expert bronchoscopists. All 10 expert bronchoscopists completed a realism survey and observational trial after CBBS performance. RESULTS: The satisfaction survey showed that the CBBS training program significantly increased participants' satisfaction (p = 0.002) and interest in learning (p < 0.001). The realism survey by the 10 expert bronchoscopists indicated that CBBS provides a favorable degree of realism with regard to the mechanical and visual parameters examined. Analysis of the performance results showed that the following parameters were capable of differentiating the participants by level of expertise: total procedure time (p = 0.002), percentage of bronchial segments entered (p = 0.012), percentage of bronchial segments identified (p < 0.001), percentage of repeated bronchial segments entered (p = 0.004), percentage of pathologies identified (p < 0.001), number of times that the bronchoscope tip collided with airway walls (p = 0.013), and number of times oral instruction was needed (p = 0.01). CONCLUSION: CBBS is a valid training method that increases interest in learning and provides a favorable degree of virtual realism. It can also distinguish various levels of competence at actual bronchoscopy and may have a useful role in the bronchoscopic training curriculum.  相似文献   
88.
论述了颈部的局部解剖结构及常用穴位,以人迎穴为例,对针刺颈部穴位的刺法和注意事项进行阐述.  相似文献   
89.
RP-HPLC测定贯叶连翘中金丝桃素、芦丁和槲皮素的含量   总被引:1,自引:2,他引:1  
樊秦  台育秦 《中国药师》2005,8(4):308-309
目的:采用高效液相法测定贯叶连翘中的金丝桃素、芦丁和槲皮素的含量方法.方法:色谱柱为Symmtry C18(4.6mm×250 mm,5μm),检测波长分别为588 nm,359 nm,流动相分别为甲醇-乙腈-1.0%磷酸二氢钠溶液(340:12:7)和甲醇-水(40:60).结果:线性范围分别在0.02704~0.1352μg和0.264~1.32μg,0.052~0.260μg内良好,回收率分别为98.39%(n=3)、98.56%(n=3)和98.85%(n=3).RSD分别为0.78%和1.01%和1.02%.结论:该法简便,精密度高,结果准确可靠.  相似文献   
90.
目的 通过对诺氟沙星葡萄糖注射液进行细菌内毒素回收干扰试验,建立定量检测诺氟沙星葡萄糖注射液中细菌内毒素的试验方法。方法采用《中国药典》2000年版附录中检测细菌内霉素的动态浊度法。结果 诺氟沙星葡萄糖注射液用细菌内毒素定量检测无干扰因素影响,内毒素回收率在50%~200%范围内。结论 使用细菌内毒素动态浊度法定量检测诺氟沙星葡萄糖注射液中细菌内毒素是可行的,可用细菌内毒素定量检查法代替家兔热原检查法。  相似文献   
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