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71.
We encountered a 38-year-old Japanese male patient with chronic myelogenous leukemia (CML), whose bone marrow and peripheral blood cells during the chronic and blastic phases contained a complex Ph1 translocation and an extra Y chromosome [i.e., 47,XYY,t(9;22;13)(q34;q11;q14)]. A karyotypic analysis of PHA-stimulated lymphocytes showed the constitutional karyotype to be 47,XYY. Thus, it was considered that CML with a complex Ph1 translocation developed in an XYY male; such a case has not been reported, so far. A B-lymphocyte cell line with the complex Ph1 translocation was established by the procedure of Epstein-Barr virus transformation. The presence of the complex Ph1 translocation in the B-lymphocyte cell line suggests that some of the B lymphocytes in this patient originated from the CML clone.  相似文献   
72.
When performing equilibrium radionuclide angiocardiography with two successive acquisition views, absolute left-ventricular volumes can be calculated using an internal standard generated by a computer in the left-ventricular cavity. The method is based on the computed ratio of maximum to global activity in the 40°-left-anterior-oblique view after background correction and on the measured depth of the left ventricle in almost-orthogonal, 30°-left-posterior-oblique Fourier first-harmonic images. The method does not require blood sampling or correction for self attenuation. The intra- and interobserver reproducibility is excellent, even in patients with severe impairment of the ventricular-contractility pattern. When compared with a classical method requiring venous-blood counting and an attenuation correction factor, the accuracy of the internalstandard method was fairly good, with a regression coefficient of 0.90.  相似文献   
73.
目的:进一步改进髌骨骨折,特别是粉碎性骨折的治疗方法.方法:取4具湿润尸体完整膝关节,保留一定的股骨胫骨长度,除股四头肌,关节囊,髌腱外去除其它软组织,伸直位固定股四头肌,制作髌骨横断骨折模型,采用4×4拉丁方设计,分别按序作四种不同固定:A、钢丝环扎加Maxon线张力带缝合;B、改良张力带固定;C、张力带钢丝固定;D、单纯钢丝环扎.用胥少汀法作生物力学测定.结果:四种固定方法固定效果有显著性差异(P<0.05),A与B效果接近,为最好,C较差,D最差.股四头肌拉力在钢丝环扎加Maxon张力带缝合和改良张力带固定,均可达体重2倍以上.结论:对某些髌骨粉碎骨折,不适合改良张力带固定,则钢丝环扎加Maxon线张力带缝合效果最佳,该方法可满足早期功能锻炼,尽早恢复膝关节功能.  相似文献   
74.
75.
IntroductionPRECICE intramedullary magnetic lengthening nails, introduced in 2011, have changed the landscape of long bone limb lengthening. The implants have a stroke ranging from 5 to 8 cm, but it may be desirable to perform part of the lengthening at one treatment, allow bone healing, leave the implant in place, dormant, and then return one or more years later to re-lengthen with the same implant. We call this the “sleeper” nail concept. This strategy may be gentler for the joints and soft tissues. Would the nail mechanism still be functional one or more years later?MethodsWe tested 102 intact, consecutively explanted nails. Using a “fast magnet,” the male part was lengthened to 5 mm short of its maximum stroke capacity and retracted back to 35 mm (all nails start with the male part exposed 30 mm). The nails passed the test if the male part succeeded in lengthening to 5 mm short of the maximum stroke capacity and back to 35 mm (or only retract in case fully deployed at testing). During our testing, the nails were prevented from reaching their full capacity of lengthening/retraction to avoid jamming the gears. Failure was defined as the inability or partial ability to complete the process.ResultsEighty-six nails (84.3%) performed successfully according to our testing standard. When comparing successful and failed nails in terms of nail type, generation, diameter, length and in vivo interval, there was no statistical significance. Comparing both groups in terms of status at testing (fully deployed or not) showed statistical significance with 9 of the 16 failed nails fully deployed at testing (p < 0.001).ConclusionDormant PRECICE nails can be reactivated for further lengthening. The results imply that full deployment may damage the mechanism, making future re-use by retracting and then re-lengthening unsuccessful. The candidate nails for this purpose should not have any signs of clear damage (bending or breakage) and should not have been fully deployed. However, surgeons and patients should be aware of the need for possible nail exchange if the “sleeper” nail fails to wake up.Level of evidenceLevel IV case series analysis of retrieved surgical implants.  相似文献   
76.
BackgroundHigh velocity gunshot fractures usually seen in conflict zones, often mandate external fixation due to delayed presentation and associated contamination. In the presented observational study, we managed high velocity gunshot fractures of humerus with adequate debridement and primary plate osteosynthesis under controlled conditions with gratifying results.Material and MethodsEighteen consecutive cases of fracture of the humerus secondary to high velocity gunshot wounds with ages ranging from 28 to 45 years reporting within 6 h of the initial injury formed our study group. Immediate debridement, lavage and primary plate osteosynthesis was carried out following hemodynamic stabilisation and intravenous antibiotics. All the cases were followed up at 2, 4, 6 months, 1 year and then annual follow-up including telephonic follow-up for six patients.ResultsFifteen cases of Gustillo Anderson type III A, two of type III B and one of type III C were managed with primary plate osteosynthesis. Brachial artery injury was addressed immediately, however injured radial nerve ends were tagged. Five cases showed delayed/non-union and were managed with decortication and autologous bone grafting. Two cases of deep infection could be managed with implant retention till union. The implants were removed following fracture consolidation. All the fractures united and no patient was left with sequelae of chronic infection.ConclusionTimely presentation of high velocity gunshot fractures of humerus teamed up with adequate debridement, soft tissue management and primary plate osteosynthesis can offer satisfactory outcomes. Associated vascular injury needs immediate attention. Nerve injuries can be addressed in a staged procedure. Our results have been satisfactory and add to the scant literature available on the subject, however further studies are warranted.  相似文献   
77.
目的 探讨微创经椎间孔入路腰椎椎间融合术(MIS-TLIF)中横突定位法置钉治疗腰椎退行性疾病的可行性.方法 回顾性分析2017年1月—2019年5月在新华医疗集团新华医院接受MIS-TLIF治疗的70例腰椎退行性疾病患者的临床资料,其中采用横突定位法置钉33例(观察组),采用传统人字嵴定位法置钉37例(对照组).记录并比较2组术中出血量、透视次数、置钉时间、一次置钉成功率、置钉优良率、关节突关节破坏率,在术前、术后3个月和末次随访时采用Oswestry功能障碍指数(ODI)、疼痛视觉模拟量表(VAS)评分评价患者腰椎功能及疼痛程度.结果 所有手术顺利完成,患者随访16~36(23.18±3.91)个月.观察组置钉时间、透视次数、关节突关节破坏率显著低于对照组,一次置钉成功率、置钉优良率显著高于对照组,差异均有统计学意义(P<0.05);术中出血量组间差异无统计学意义(P>0.05).2组术后3个月、末次随访时VAS评分和ODI均较术前显著改善,差异均有统计学意义(P<0.05),组间比较差异无统计学意义(P>0.05).结论 MIS-TLIF术中采用横突定位法置钉治疗腰椎退行性疾病近期疗效良好,可减少置钉时间,提高置钉成功率与准确率.  相似文献   
78.
Our ability to additively combine two learned internal models was investigated by studying the forces people generate when lifting objects with a precision grip. Subjects were required to alternately lift two objects of identical physical appearance but differing weight. Grip force scaling prior to lift-off was used to estimate the output of the internal model associated with each object. Appropriate internal models were formed when alternately lifting two objects of different weight. The objects were then combined by stacking them one upon the other, and the combined object was lifted. Results show that subjects can additively combine internal models of object dynamics but the sum is biased by a default estimate of the objects weight.  相似文献   
79.
次黄嘌呤/黄嘌呤氧化酶体系产生的氧自由基在体外能明显增加血中板膜微粘度,脂质过氧化代射产物丙二醛含量,血小板胞内游离钙浓度和血小板5-羟色胺的释放量。0.03u/ml的蛇毒抗栓酶明显抑制前二种效应,但促进血小板释放5-羟色胺,增加血小板胞内游离钙浓度,结果表明蛇毒抗栓酶对血小板膜有保护作用。  相似文献   
80.
Three-dimensional finite-element models provide a method to study the relationship between human scalp potentials and neural current sources inside the brain. A new formulation of dipole-like current sources is developed here. Finiteelement analyses based on this formulation are carried out for both a threeconcentric-spheres model and a human-head model. Differences in calculated scalp potentials between these two models are studied in the context of the forward and inverse problems in EEG. The effects of the eye orbit structure on surface potential distribution are also studied.  相似文献   
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