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1.
经颅彩色双功超声是一种新型、无创的超声诊断仪,高空间分辨率显示颅内血管和脑实质的结构,笔者查阅了近年来相关文献,主要综述经颅彩色多普勒血流显像在颅脑血管疾病中的诊断价值,同时讨论二维经颅超声的应用及新的实验性显像技术。  相似文献   
2.
吴军 《医疗卫生装备》2010,31(6):100-102
分析了NIKKISO DBB-27型血液透析机液路系统的系统结构及各组成部分的工作原理,并对相关故障报警的诊断和排除进行了详细论述,为及时、准确地诊断和排除血液透析机的故障提供了理论基础。  相似文献   
3.
The data concerning the value of duplex sonography in diagnosingparenchymatous renal allograft dysfunction are controversial.Most early studies did not take into consideration the manyfactors influencing resistance parameters. We therefore performeda prospective, biopsy-controlled study with exclusion of allknown sources of error regarding resistance parameters. Furthermorewe investigated the value of a new resistance parameter, thesystolic deceleration percentage. Forty-seven duplex sonographicstudies were performed on 43 patients (30 male, 13 female, medianage 47 years, range 7–70). Fourteen studies were doneon normally functioning grafts (control group) an average of33 days after transplantation. Thirty-three studies were performedon dysfunctional grafts immediately prior to biopsy. Graftswhich had been transplanted more than a year previously or withvascular findings or any other clinical or sonographic pathologyprobably explaining function deterioration were excluded. Inall patients, the resistive index (RI), pulsatility index (PI)and systolic deceleration percentage (DP) were calculated inthe main renal artery and in the interlobar artery. Of the 33grafts with dysfunction, nine had vascular rejection (VR), 11interstitial rejection (IR), 11 cyclosporin A toxicity (CAT)and two other histologies (OR). The mean RI in normal grafts(NO) was 0.71±0.06 in the main artery and 0.68±0.06in the interlobar artery, in VR 0.86±0.12 and 0.80±0.18,in IR 0.72±0.05 and 0.70±0.07, in CAT 0.67±0.06and 0.65±0.07 and in OR 0.64±0.07 and 0.60±0.01.For PI, the values were 1.45±0.23 and 1.41±0.28(NO), 3.5±2.13 and 2.92±2.16 (VR), 1.55±0.26and 1.46±0.33 (IR), 1.32±0.25 and 1.27±0.26(CAT) and 1.30±0.34 and 1.13±0.04 (OR). For DPwe calculated 28±5% and 29±6% (NO), 43±14%and 36±6% (VR), 29±9% and 27±9% (IR), 31±8%and 32±7% (CAT ) and 32±4% and 28±3% (OR).The sensitivity/specificity for VR with a cutoff mean+2 SD was0.44/1 for RI, 0.55/0.97 for PI and 0.33/0.89 for DP. It wasconcluded that:(1) despite the high selection of our patientgroup, diagnostic accuracy of duplex sonography for diagnosingparenchymatous function disorder in renal allograft remainsinsufficient; (2) in vascular rejection only, the resistanceparameters differ significantly from the values of normal allografts;(3) the higher the cutoff of resistance parameters, the betterthe specificity and the worse the sensitivity for diagnosingvascular rejection; (4) of all investigated resistance parameters,the RI is the most practical due to a simple measurement technique.  相似文献   
4.
Summary The case of a 10-year-old boy with post-traumatic priapism after perineal trauma is presented. Interdisciplinary treatment using angiography and selective catheter embolization for juvenile high-flow priapism is demonstrated. The literature and the diagnostic possibilities resulting from color duplex sonography are discussed.   相似文献   
5.
OBJECTIVE: The purpose of this study was to investigate the incidence of the retroaortic left renal vein (RLRV) in patients with varicocele. METHODS: The left renal vein was ultrasonographically investigated for the presence of the RLRV in 140 patients with varicocele and a control group of 137 age-matched patients. The main diagnostic criteria for varicocele were the presence of a varicose vein with a diameter of 3 mm or larger at rest and with a reflux lasting more than 2 seconds during the Valsalva maneuver. The RLRV was defined as a posterior course of the left renal vein to the aorta at the level of the origin of the superior mesenteric artery. RESULTS: The RLRV was observed in 13 (9.3%) of the 140 patients with varicocele and 3 (2.2%) of the control patients. The incidence of the RLRV was found to be significantly higher in patients with varicocele compared with the control patients (P = .018, Fisher exact test). In 13 patients with the RLRV, left varicocele and bilateral varicocele were detected in 10 and 3 cases, respectively. CONCLUSIONS: In this study, the incidence of the RLRV was found to be significantly higher in patients with varicocele compared with control patients. Thus, we suggest that the presence of the RLRV may be considered one of the etiologic factors in the development of varicocele.  相似文献   
6.
肝硬化患者肾脏血液动力学的研究   总被引:3,自引:0,他引:3  
目的 研究肝硬化患者肾脏血液动力学的改变。方法 应用多普勒超声测定42例肝硬化患者肾脏血液动力学指标。并分析这些指标与肝功能及平均动脉压之间的关系。结果 不同阶段的肝硬化患者肾内血管收缩程度有明显的差异。结论 肝硬化早期即有肾血管的收缩,肝功越差肾血管收缩越明显。肾血管的收缩是全身血液动力学改变的一部分。  相似文献   
7.
8.
The aim of this paper was to establish if duplex ultrasound parameters obtained for assessment of the patency of cavernosal arteries in the penile flaccid state can give sufficient clinical information without the use of intracavernosal injection of vasodilatory drugs. We assessed mean cavernosal peak systolic velocity (PSV) in the penile flaccid state (basal PSV), and after PGE1 injection (dynamic PSV) in 339 unselected patients with erectile dysfunction. In 55 of these patients the waveform acceleration in the flaccid state was also assessed. The results of the study can be summarized as follows: (1) a significant relationship was found between basal and dynamic PSV in the 339 patients (r=0.477; p < 0.0001); (2) a basal PSV >12.5 cm/sec was predictive of a dynamic PSV >/=30 cm/sec in 129/139 (92.8%) of the patients, whereas in patients with a basal PSV or <30 cm/sec could be found; and (3) an acceleration >1 m/sec2 in the flaccid state was coupled to a dynamic PSV >30 cm/sec in 43/46 (93.5%) of the patients independent of the basal PSV. In conclusion, these results suggest that the combined duplex ultrasound assessment of PSV and waveform acceleration in the penile flaccid state can predict arterial dynamic inflow in the majority (51/55; 92.7%) of patients with erectile dysfunction, with less time and expense and less discomfort for the patient.  相似文献   
9.
一种快速检测HBV基因的荧光定量PCR法的建立   总被引:1,自引:0,他引:1  
目的:利用二聚体蝎型荧光探针技术,建立一种能用于临床的快捷、敏感、特异、价格低廉的HBV实时荧光定量PCR检测方法。方法:根据HBV基因组保守区域precore/core设计二聚体蝎型荧光探针和引物,构建质粒标准品,优化荧光定量PCR条件,并进行方法学评价。结果:所建方法的检测范围为10^1~10^8 copies/μl,灵敏度达到10copies/μl,低拷贝样品的批内和日间重复性(CV)分别为1.71%和2.57%,高拷贝样品的批内和日间GV,分别为3.00%和3.86%。与商品化TaqMan试剂盒相比,本法阳性检出率较高,且检测时间缩短了45min(约减少1/3),成本降低50%。结论:成功建立了快速检测HBVDNA的二聚体蝎型荧光定量PCR方法,为研发适合临床应用的HBV基因定量检测试剂盒奠定了基础。  相似文献   
10.
Pneumatic chipping hammer and ultrasonic impact peening were used to relieve the welding residual stress of 2205 duplex stainless steel by manual argon arc welding, and the influences of these mechanical shock treatment technologies on the residual stress, microstructure, and corro-sion resistance of the welding seam were studied. Results showed that after pneumatic chipping hammer or ultrasonic impact peening, a small amount of plastic deformation occurred in the welded joint of 2205 duplex stainless steel, which led to an increase in the dislocation density in the microstructure. Meanwhile, the stress state of the welded joint changed from the residual tensile stress to the residual compressive stress. The maximum residual compressive stress could reach −579 MPa. The combined action of the two effectively improved the corrosion resistance of the welded joint. Among them, the best overall effect was the ultrasonic impact peening tech-nology.  相似文献   
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