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21.
D. Grant Richards Kevin G. Whithear Peter C. Scott Robin B. Gasser 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2006,51(2):156-159
Coccidiosis of chickens, caused by species of Eimeria (Protozoa, Apicomplexa), is an intestinal disease of major economic importance worldwide. In the present study, the reproductive
characteristics of a precocious line (designated E. tenella Rt3+15) from Australia were investigated in chicken embryos and the implications of the findings briefly discussed. 相似文献
22.
Phase II clinical trials are performed to investigate whether a novel treatment shows sufficient promise of efficacy to justify its evaluation in a subsequent definitive phase III trial, and they are often also used to select the dose to take forward. In this paper we discuss different design proposals for a phase II trial in which three active treatment doses and a placebo control are to be compared in terms of a single‐ordered categorical endpoint. The sample size requirements for one‐stage and two‐stage designs are derived, based on an approach similar to that of Dunnett. Detailed computations are prepared for an illustrative example concerning a study in stroke. Allowance for early stopping for futility is made. Simulations are used to verify that the specified type I error and power requirements are valid, despite certain approximations used in the derivation of sample size. The advantages and disadvantages of the different designs are discussed, and the scope for extending the approach to different forms of endpoint is considered. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
23.
目的 :探讨影响双胎妊娠临床结局的相关因素。方法 :回顾性分析 12 8例双胎妊娠临床结局与胎方位、分娩方式、孕周、新生儿体重、新生儿窒息之间的关系。 结果 :胎方位、孕周、胎儿体重及分娩方式均影响围产儿预后。 结论 :加强孕产期保健 ,提高产科质量能改善双胎妊娠围产儿的预后。 相似文献
24.
17β-雌二醇对子宫内膜异位症患者在位子宫内膜间质细胞β-catenin mRNA和蛋白表达的影响 总被引:2,自引:0,他引:2
目的研究17β-雌二醇(17β-E2)对子宫内膜异位症(内异症)患者在位子宫内膜间质细胞β-catenin mRNA和蛋白表达的影响,探讨Wnt/β-catenin信号通路在介导雌激素促进内异症发生发展的作用。方法体外分离培养内异症患者在位子宫内膜间质细胞。用不同浓度17β-E2处理子宫内膜间质细胞48 h;此后选用10-10mol/L 17β-E2处理子宫内膜间质细胞12、24和48 h,逆转录聚合酶链反应(RT-PCR)和免疫印迹法(Western blotting)检测17β-E2处理前后子宫内膜间质细胞β-catenin mRNA和蛋白的表达水平。同法分析雌激素受体拮抗剂ICI182,780(10-6mol/L)对17β-E2促进β-catenin mRNA和蛋白表达的影响。免疫组织化学染色观察17β-E2作用后β-catenin在子宫内膜间质细胞中的定位。结果17β-E2能明显促进内异症患者在位子宫内膜间质细胞β-catenin mRNA和蛋白的表达,并呈剂量和时间依赖性,于10-10mol/L作用48 h最明显。雌激素受体拮抗剂ICI182,780能明显抑制17β-E2对子宫内膜间质细胞β-catenin mRNA和蛋白的表达。免疫组织化学染色发现17β-E2能促进β-catenin在子宫内膜间质细胞核内的表达。结论雌激素可能通过激活Wnt/β-catenin信号通路促进内异症在位子宫内膜的异位种植。 相似文献
25.
Objective: Severe scoliosis refers to scoliosis with serious and stiff curve. It always combins with trunk imbalance in coronal and sagittal contour. Besides complex pathological changes, cardiopulmonary deficits and other concomitant diseases increase treatmental difficulties. So the treatment of severe scoliosis is always a great challenge to spine surgeon. Methods :Thirty-six patients with severe scoliosis received one stage posterior correction followed by anterior release during July 1997 to January 2003, including 9 males and 27 females. Mean age was 17.2 years. Of them, 33 was idiopathic scoliosis and 3 was neurofibromatosis scoliosis( Cobb angle: 85-116 degree); 20 cases were abnormal in sagital plane. Three-dimensional devised instrumentation were applied such as CD, CD-Horizon, TSRH or Isola in posterior procedure followed by anterior release during the same anesthesia. 31 cases of this group received thorac icplasty. Results: The correction in the frontal plane achieved an average of 48.5%. In the sagittal plane, the pathological shape of the spine was reduced and distinctly ameliorated. 80. 6% of the patients maintained or achieved balance of sagittal plane. There were no complications of severe neurological deficit, hook displacement, rod broken, and deep infection at follow-up. One case occurred traumatic pleurisy after operation and another appeared pseudarthrosis 2 years later. One case demonstrated imbalance 11 months after operation. One patient was presented loss of correction more than 10 degree at one year follow-up and 5.2 degree in average. Conclusion:The study indicates that the one stage posterior correction combined with anterior release in treatment of severe scoliosis can achieve satisfactory correction. Appropriate choice of cases, preoperational detailed assessment and application of SEP and wake-up test during operation can possibly reduce severe complication. The long-term outcomes still need further observation. 相似文献
26.
立体着床模型--小鼠囊胚与子宫内膜的共培养 总被引:1,自引:0,他引:1
目的:建立小鼠囊胚体外着床的三维模型,为着床机制的研究提供重要工具.方法:将小鼠囊胚与其自身子宫内膜分别共培养在空气、含500,750和950 mL/L O2的混合气体与组织培养液的气液界面上,比较不同O2浓度下小鼠囊胚的贴附率,确定体外共培养的最佳O2浓度;同时将确认有囊胚贴附的子宫内膜取出作HE染色.结果:不同O2浓度下,囊胚的贴附率分别为64.75%,47.86%,42.37%和30.97%,x2检验提示其差异有显著性(x2=28.145,P=0.000);且随着混合气体中O2浓度的逐渐升高,囊胚贴附率呈逐渐降低趋势.因此50 mL/L CO2 950 mL/L空气对囊胚与子宫内膜的共培养是最有利的;同时,囊胚贴附子宫内膜后并无扩展行为而是直接侵入子宫内膜.结论:50 mL/L CO2 950 mL/L空气最有利于囊胚与子宫内膜的共培养;且囊胚贴附子宫内膜后不发生外延生长,而是直接侵入子宫内膜.本实验成功地建立了小鼠囊胚体外着床的三维模型. 相似文献
27.
28.
Hannie G. A. Bouman Monique L. A. Broekhuizen A. Mieke J. Baasten Adriana C. Gittenberger-De Groot Arnold C. G. Wenink 《Anatomical record (Hoboken, N.J. : 2007)》1995,243(1):101-108
Background: In a recently developed chick model the teratogen retinoic acid has appeared to induce a spectrum of double outlet right ventricle, which needs further detailed evaluation. It is known that retionic acid is able to induce cardiac malformations. Although the exact mechanism is not known, an interaction with neural crest cell function is thought to exist. Methods: After treatment with 1 μg all-trans retinoic acid at Hamburger and Hamilton stage 15 and reincubation until stage 34 of development 41 chicken embryos were evaluated macroscopically and microscopically, supported by graphic reconstructions. These retinoic acid treated embryos were compared with a control group (n = 8). Results: The retinoic acid treated embryos could be divided in three groups. Group 1 (23/41) had an intact septum, group 2 (11/41) had an isolated ventricular septal defect (VSD), and group 3 (7/41) had a double outlet right ventricle (DORV). Besides, in the group with an intact septum 11 hearts showed an abnormal course of the subaortic outflow tract. In the group with DORV a straddling tricuspid orifice (7/8) and a double inlet left ventricle (1/8) could be distinguished. Considering the external contour, the hearts in the DORV group all showed a dextroposed arterial pole. Malformed pharyngeal arch arteries were found in all three groups (11/41) and with a great diversity. Conclusions: The present cardiac malformations in the chicken as a result of retinoic acid treatment are part of a continuous spectrum, varying from hearts with an intact ventricular septum and a normal course of the subaortic outflow tract to a double outlet right ventricle with a straddling tricuspid orifice or even a double inlet left ventricle. A remarkable observation in this spectrum concerns the correlation of malformations of the inflow and outflow tracts, which is explained as a cardiac looping disturbance. The disturbance of the looping process seems to lead to malalignment of septal components, although, in the chick, retinoic acid does not in general interfere with the formation of these septal components themselves. © 1995 Wiley-Liss, Inc. 相似文献
29.
第二产程产妇自由体位分娩效果的研究 总被引:8,自引:0,他引:8
目的 探讨产妇在第二产程中采取自由体位对分娩效果及舒适瘦的影响。方法 随机将152例初产妇分为观察组77例和对照组75例。观察组产妇在第二产程根据产妇的意愿采取半卧位、侧卧位、蹲位、坐位等自由体位,接生时采用半卧蹲坐位。对照组产妇采取床头抬高30°的截石位分娩。比较2组第二产程的长度及产后的舒适度。结果 观察组第二产程较对照组缩短(P〈0.01),产后双下肢酸痛、麻木不适较对照组显著减轻,舒适度增加。结论 第二产程自由体位可有效缩短产程并缓解分娩体位的不适。 相似文献
30.
目的 回顾性研究终末期肾脏疾病(end stage renal disease,ESRD)血液透析病人原发疾病构成及其相关因素。方法 收集ESRD血液透析病人1108例,分析其原发疾病构成、年龄、性别、透析治疗持续时间、转归、生存率和死亡原因。结果 301例病人透析时间超过3个月,其中43.9%仍在进行血液透析治疗,最长者已存活13年;13.0%病人已行肾脏移植;19.9%转至外院治疗;7.3%改为腹膜透析;1.3%因经济困难放弃治疗;14.6%病人死亡。ESRD维持性血液透析病人1年生存率为93.53%,3年生存率为68.92%。5年生存率62.51%。死亡原因为心血管事件占54.5%,脑血管意外占20.5%。结论 本组病人以中、老年为主,男性多见。ESRD血液透析病人主要原发疾病为慢性肾小球肾炎,主要死亡原因为心血管事件和脑血管意外。 相似文献