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排序方式: 共有460条查询结果,搜索用时 15 毫秒
1.
目的总结改良Devine治疗小儿隐匿性阴茎的效果。方法对158例小儿隐匿性阴茎患者采用改良Devine术式治疗,阴茎皮肤完全脱套后,切除发育异常的纤维肉膜组织,阴茎根部皮肤固定成角。结果 158例患儿术后阴茎均显露良好。随访105例,随访2~38个月,105例患儿阴茎均发育正常,效果满意。结论改良Devine术式是治疗小儿隐匿性阴茎的理想术式。该术式操作简单,术后恢复快,并发症少,治疗效果满意。  相似文献   
2.
两种隐匿阴茎大鼠模型的建立及比较   总被引:4,自引:3,他引:1  
目的:建立稳定的大鼠隐匿阴茎模型,为探索阴茎包埋对海绵体结构和功能的影响提供实验动物模型。方法:90只2周龄雄性SD大鼠随机均分为A、B、C3组,A组采用阴茎根部内荷包缝合法,B组采用包皮折叠缝合法包埋阴茎,C组为假手术组。在180d内观察两种方法的包埋效果。结果:A组术后4只死于急性尿潴留,5只因尿道口周围软组织感染、皮肤破溃导致包埋失败,3只因包埋过松阴茎伸出;B组术后1只死于麻醉,2只死于急性尿潴留;因阴茎发育和勃起,A组有7只、B组有10只阴茎伸出;C组1只死于麻醉。A组和B组中其余大鼠均有较好的包埋效果,A组包埋成功率为36.7%,B组为56.7%,而且可以在实验中任何时候解除包埋。结论:包皮折叠缝合法和阴茎根部内荷包缝合法均能建立稳定的、且与人类隐匿阴茎自然病程较为一致的2周龄大鼠隐匿阴茎动物模型。  相似文献   
3.
The typical fourth criterion for transient entrainment is defined when both a sudden shortening in conduction interval to and a distinct change in electrogram morphology at a bipolar recording site are demonstrated while performing overdrive pacing of a reentrant tachycardia from a single pacing site at two different constant rates. The purpose of this article was to test the hypothesis that if an intracardiac recording site showing both orthodromic and antidromic capture with entrainment pacing is located suitably distant from the circuit, sudden shortening in conduction interval to that site may occur without any significant change in the bipolar electrogram morphology (i.e., atypical form of the fourth criterion). Atrial overdrive pacing of orthodromic tachycardia was performed in 20 patients with either left anterior (12 patients) or left posterior (8 patients) accessory pathways. We investigated the effects of overdrive pacing from the proximal or distal coronary sinus, specifically effects on the electrogram interval and the electrogram morphology at the right atrial appendage. Overdrive pacing of orthodromic tachycardia from the proximal coronary sinus was performed in 10 of the 12 patients with left anterior accessory pathways; those 10 patients demonstrated the first entrainment criterion at the right atrial appendage site. Overdrive pacing of orthodromic tachycardia at still shorter cycle lengths demonstrated a sudden shortening in conduction interval to the right atrial appendage site. Despite shortening in conduction interval the morphology of the right atrial appendage electrogram was completely or almost identical to that during orthodromic tachycardia, indicating an atypical form of the fourth criterion. This criterion was not demonstrated in patients with left posterior accessory pathways. Thus, atypical fourth entrainment criterion was demonstrated during overdrive pacing of orthodromic tachycardia from the proximal coronary sinus only in patients with left anterior accessory path ways. Demonstration of atypical fourth criterion seems largely dependent on the location of the accessory pathway, the pacing, and the recording sites.  相似文献   
4.
Abstract Daan's two process model is known to be one of the most powerful models, covering various situations from free-running to sleep deprivation. In this study, bifurcation properties of the model dynamics as function of a gap, D , between the threshold processes are clarified using a circle map. As a function of D , we will show that the model has the different types of the mutual entrainment regions that are intervened by the tangent bifurcation. The variable behavior of human circadian rhythm is suggested to be systematically understood based on the bifurcation properties of the two process model.  相似文献   
5.
6.
Rats with hypothalamic and septal electrodes were maintained in continuous test environments where bar-press responses produced brief reinforcing electrical stimulations. Long-term trends in response emission were measured under continuous exposure to light, dark and 12 hr light-dark alternations. In addition, transient behavioral adjustment to sudden 180 degrees phase shifts in the light-dark schedule was studied. The ambient light condition was found to control the period and phase of the circadian rhythm of brain self-stimulation behavior, as quantified by Fourier analysis. The circadian period was greatest under constant light (up to 24.90 hr under dim illumination), and approximated 24.00 hr under constant dark. Successful nocturnal entrainment to 12 hr light-dark alternations was obtained, with the peak of the 24 hr Fourier fundamental occurring in the middle-to-late dark segments. Three to 11 days were required for re-entrainment to 180 degrees light-dark phase shifts, during which the behavioral oscillation period increased to values comparable to periods under constant light. The rate of re-entrainment appeared to be proportional to illumination intensity during light segments.  相似文献   
7.
A case of permanent junctional reciprocating tachycardia withpost-mortem documentation of an accessory atrioventricutar pathwayas the substrate of the arrhythmia is reported. Tachycardiahad lasted for 15 years and showed a retrograde P wave (P')and R–P' longer than P'–R interval. The tachycardiacircuit utilized a concealed posterior septal accessory pathwayas the retrograde limb. Because the arrhythmia was disablingand unresponsive to pharmacological treatment, the patient underwentclosed chest ablation of the His bundle. After the procedure,no anterograde or retrograde conduction over the normal conductionsystem was observed; anterograde conduction over the anomalouspathway showed decremental properties. Because of previous myocardialinfarction, the patient developed a ventricular aneurysm anddied suddenly 5 months after His bundle ablation. Histologicalexamination of the heart revealed a group of tiny fibromuscularbundles joining the lower rim of the coronary sinus outlet tothe summit of the interventricular septums; the anomalous atrioventricularconnection pursued a sinuous, tortuous path. The geometricaldisposition of the accessory pathway may have been responsiblefor the decremental properties of conduction observed duringlife.  相似文献   
8.
在1 000 mm的圆塔内,采用空气-水系统对十字旋阀塔板的流体力学性能进行了测试,考察了液流强度、出口堰高、开孔率等因素对塔板压降、雾沫夹带及泄漏性能的影响。结果表明:在小液流强度下,十字旋阀塔板上气体分散均匀,泡沫层高度稳定,气液接触充分,具有较好的流体力学性能和优势。  相似文献   
9.
目的 探讨隐匿抑郁症患者的脑电变化特点.方法 经神经内科门诊筛查选择86例以躯体化症状为主诉的隐匿抑郁症患者作为观察组,另设65例健康体检者作为正常对照组,两组均行脑电图、脑干听觉诱发电位和视觉诱发电位检查.结果 观察组脑电图异常率63.95%,正常对照组异常率仅为13.85%,两组比较有显著性差异(P<0.05).观察组脑电图以轻度异常为主,局限性异常多见于额叶,诱发电位以各主波及波间潜伏期较正常对照组显著性延长.结论 以躯体化障碍为主诉的抑郁症患者其脑电图异常率明显高于正常人,且诱发电位潜伏期延长.  相似文献   
10.
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