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41.
The effects of acute blood volume reduction induced by haemodialysison diastolic time intervals were studied in 19 patients by echo-and phonocardiography. Haemodialysis significantly decreasedleft ventricular diameters. The isovolumic relaxation time wasprolonged and negatively correlated with left ventricular enddiastolic dimensions. To study the effect of load reductionon left ventricular filling time, cardiac cycles with the sameRR interval, before and after haemodialysis, were compared.At any given RR interval dialysis resulted in a significantprolongation of the filling time. This study shows that diastolictime intervals are dependent on left ventricular loading conditions,and this effect should be considered when these time intervalsare evaluated in the clinical setting. 相似文献
42.
The objective of this demonstration project was to determine if school-based harm minimization drug education was potentially acceptable and effective for junior and senior high school students in Nova Scotia. We conducted a four-year quasi-experimental intervention using mixed quantitative and qualitative methodologies. The intervention was a co-operative participatory research project with various activities determined by the participants. The project involved a partnership of four schools, two school boards, two regional addiction services, the provincial department of health, and a university. The outcomes evaluation was based on a sample of 1117 and 849 students in the intervention schools, compared with 3755 and 4247 students in the rest of the province, in 1998 and 2002, respectively. The evaluation of acceptability was based on an analysis of 491 documents generated from 1998 to 2002. The outcomes of effectiveness were specific risks and harmful consequences associated with substance use. We found that harm minimization was an acceptable approach to drug education targeting the senior high school population, and there was also some evidence of effectiveness in that age group in that the prevalence of several risks and negative consequences of substance use decreased significantly in the intervention schools relative to the rest of the province. In junior high school, harm minimization was found to not be an acceptable approach to drug education. This demonstration project provides evidence that school-based harm minimization may be acceptable and effective in senior high schools but may not be acceptable in junior high schools. 相似文献
43.
A Comparative Study on the Close Reduction of Arytenoid Dislocation under Indirect and Direct Laryngoscope 总被引:3,自引:0,他引:3
To assess the curative effects of different reduction techniques on the dislocation of cricoarytenoid joint caused by intubation,indirect laryngoscope (IL) and direct laryngoscope (DL) were utilized for the closed reduction of the displaced arytenoid under local anesthesia.23 patients who underwent the reduction for dislocated arytenoid under IL or DL from January 1991 to June 2001 were reviewed.The data were collected on the duration of the laryngeal injury,times of receiving reduction,side-effects after the treatment and the period for voice to returen to normal.The relationship between the duration of the laryngeal lesion and the period of the voice rehabilitation was examined.13 patients received the reduction under IL and 10 patients under DL,Except the times of the reduction,which showed significant difference,no differences were found between IL group and DL group in the course and the period of voice rehabilitation,as well as sore throat after the manipulation.The patients‘ voice recovery was positively related to their course of disease in both IL and DL group.It is coucluded that the recovery of normal voice is obviously affected by the duration of arytenoid dislocation.The reduction under Il is as effective as under DL in the treatment of arytenoid dislocation.Reduction by DL is better suit the patients with long time course of disease. 相似文献
44.
Elie Mousseaux Iiana Idy-Peretti Jacques Bittoun Odile Jolivet Eric Bourroul Anne Tardivon Pierre Pronneau Jean-Claude Gaux 《Journal of magnetic resonance imaging : JMRI》1994,4(5):719-724
Magnetic resonance imaging maps of velocity were acquired with a 1.5-T system in 10 subjects in a plane perpendicular to the main pulmonary artery. Velocity images were successively acquired with a method developed from Fourier-encoding velocity imaging (FEVI) principles with eight gradient steps and one excitation, and with two-point phase-subtraction mapping. Reconstruction in FEVI was implemented by zero-filling interpolation around the eight gradient steps and then around the four central steps. The methods were compared by using estimates of noise in velocity measurements based on the difference between the experimental map and a smooth fitted map. For the same acquisition time, FEVI with four encoding steps was more precise in velocity measurements than phase mapping. Precision was further increased by the use of eight encoding steps, but acquisition time was doubled. 相似文献
45.
介绍了东京都日野市确立生活垃圾收费标准的方式及为推行这一政策所采取的相关举措,分析了收费前后的垃圾减量效果及居民的环境意识变化,提出了对我国探索城市生活垃圾收费改革的启示. 相似文献
46.
闭合复位经皮螺钉内固定治疗跖跗关节损伤 总被引:9,自引:0,他引:9
目的探讨应用闭合复位经皮螺钉内固定治疗跖跗关节损伤的临床疗效。方法自2003年1月~2005年6月应用闭合复位经皮螺钉内固定治疗跖跗关节损伤26例。按照Myerson分类:中间柱损伤13例,内侧、中间柱合并损伤7例,内侧、中间、外侧柱三柱损伤6例。结果本组切口均一期愈合,平均手术时间为40min(30~70min),切口长度平均为5mm;所有患者获平均11.4个月(6~17个月)随访,根据美国足踝骨科协会(AOFAS)评分平均为87分,患者术后平均5.3个月(3~11个月)恢复正常生活。结论闭合复位经皮螺钉内固定手术创伤小,软组织并发症低,能有效治疗跖跗关节复合体损伤;中间柱复位并沿Lisfranc韧带方向插入螺钉内固定是重建跖跗关节复合体稳定性的关键。 相似文献
47.
A restricted field of view (rFOV) approach for imaging a dynamic time series of volumes of limited spatial extent within a larger subject is described. The shorter readout with rFOV-MRI can be exploited to either limit image artifacts or increase spatial resolution. To accomplish rFOV imaging of a multislice volume for a dynamic series, an outer volume suppression (OVS) preparation that saturates signal external to a cylinder through the subject is followed by slice-selective excitation and a spiral readout. The pass- and stopband efficiencies of the OVS in an agar gel phantom were 97% (+/-1.5%) and 3% (+/-1%), respectively. Profiles of the temporal signal-to-noise ratio (SNR) were measured in a phantom and an adult brain. The rFOV sequence reduced distortions from off-resonance signal and T2*-induced blurring compared to a conventional sequence. Sequence utility is demonstrated for high-resolution rFOV functional MRI (fMRI) in the visual cortex. The rFOV sequence may prove to be useful for other multislice dynamic and high-resolution imaging applications. 相似文献
48.
桡骨颈骨折经皮撬拨复位的远期疗效 总被引:1,自引:0,他引:1
马元璋 《中国骨与关节损伤杂志》1994,(4)
用经皮撬拨复位治疗桡骨颈骨折56例,其中复位良好46例,较好6例和不良4例;经3年7个月平均随访,复位良好和较好的44例中,后期疗效良好32例,较好11例和一般1例。骨折解剖复位、撬拨复位的手术损伤轻和石膏固定时间较短是后期疗效满意的关键。成人桡骨颈骨折伴肘内侧副韧带严重损伤比儿童多见,但儿童桡骨颈骨折严重倾斜移位和完全移位比成人多见,后期疗效更满意。 相似文献
49.
50.
3—氯—4—氟苯胺的生产与研究概况 总被引:1,自引:0,他引:1
张水泉 《中国医药工业杂志》1991,22(7):327-330
评述了3-氯-4-氟苯胺的实验室研究和工业生产现状,特别对氯化、硝化、氟化和还原等反应中间体的制备及其质量作了分析。 相似文献