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91.
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93.

Purpose

We assessed the location of urethral arteries in patients with urethral stricture using color Doppler ultrasound.

Materials and Methods

We performed 41 color ultrasound studies of the urethra in 33 patients 17 to 76 years old. The linear array transducer was placed on the ventral surface of the penis and perineum to image the urethra and periurethral structures. In addition of evaluating the extent of stricture disease, color Doppler ultrasound determined the location of the urethral arteries at the segment with stricture.

Results

The number and site of the urethral arteries vary among individuals. Contrary to the common belief that these arteries are located at the 3 and 9 o'clock positions, we have found that in the bulbous urethra the arteries are at the 1 to 2 o'clock positions in 14% of cases, 3 to 4 in 22%, 5 to 6 in 17%, 7 to 8 in 18%, 9 to 10 in 18% and 11 to 12 in 11%. The arteries may be close to the surface of the urethral lumen, especially in patients who have undergone previous urethral procedures. Preoperative evaluation of urethral artery location may be helpful for preventing arterial bleeding at visual internal urethrotomy.

Conclusions

Color Doppler ultrasound can effectively assess the extent of stricture disease and urethral artery sites. Because the location of the urethral arteries varies among patients, individual preoperative assessment is advisable. Color Doppler ultrasound is currently our imaging method of choice for evaluating strictures of the pendulous and bulbous urethra.  相似文献   
94.

Purpose

We determine how transurethral resection of the ejaculatory ducts performed for infertility affects seminal parameters and pregnancy outcomes in patients with partial ejaculatory duct obstruction due to a congenital or acquired etiological factor.

Materials and Methods

Based on history and physical examination, hormonal profiles, semen analyses, transrectal ultrasonography and vasography findings partial ejaculatory duct obstruction was diagnosed in 14 men a mean of 30 years old who presented for infertility evaluation. Patients were grouped according to congenital or acquired cause of obstruction. Transurethral resection of the ejaculatory ducts was performed using the standard resectoscope loop technique. Clinical outcome was assessed by postoperative analyses of seminal parameters and pregnancy reports.

Results

Transurethral resection of the ejaculatory ducts significantly improved semen quality (ejaculate volume and percentage of sperm motility) in all patients in the congenital group, while all but 1 (83%) had an improved sperm count. Pregnancy was achieved via sexual intercourse by 66% of the patients an average of 5.7 months postoperatively. Of the acquired etiological factor group 37.5% had improved semen quality after transurethral resection of ejaculatory duct and 12.5% achieved pregnancy via sexual intercourse. Postoperative complications occurred at a similar rate in each group (33%). However, complications in the congenital etiology group were minor, while 25% of the men in the acquired group had significant impairment of seminal parameters after transurethral resection of the ejaculatory ducts.

Conclusions

Semen quality improvement and pregnancy outcome after transurethral resection of the ejaculatory ducts for partial ejaculatory duct obstruction differ significantly according to the main etiological cause of obstruction. An equivocal diagnosis of partial obstruction and technical problems during transurethral resection of the ejaculatory ducts may contribute to failure. However, in some cases the reason for failure remains unclear.  相似文献   
95.
评价无支架异种生物瓣膜主动脉瓣替换术后2年左室功能的变化。将80例同期施行主动脉瓣替换病人分为2组,50例(年龄69.3±9.3岁)应用TorontoSPVTM瓣;30例(年龄71.6±7.7岁)作为对照组接受支架人工瓣膜替换。术前、术后1、6、12及24个月间记录M型及Doppler超声心动图,采用计算机图像数字分析,定量测定左室功能的变化。随访期间,Toronto组主动脉瓣跨瓣压差为0.8±0.6kPa(6.0±4.5mmHg),明显低于对照组2.3±0.9kPa(17.3±6.8mmHg);术后1个月,左室心肌质量下降25%,左室+Vcf及-Vcf明显增加(2.0±0.8/1.4±0.3s-1,P<0.01;2.8±1.2/1.8±0.7s-1,P<0.01)。术后6个月,左室功能进一步改善,心室肥厚的消退更趋完全,该变化在其后的随访期间保持稳定。结论:与支架瓣膜相比,无支架异种生物瓣膜具有较大瓣口开放面积及低跨瓣压差,这促进了术后左室功能的恢复及病理性肥厚的逆转  相似文献   
96.
亚临床甲状腺功能亢进和甲状腺功能减退属于试验诊断。2002年美国甲状腺协会、美国临床内分泌医师协会和内分泌腺协会的委员组成的一个专家小组,明确了亚临床甲状腺疾病的概念,回顾了涉及风险和治疗益处的文献,并且建议进行评估和人口筛查。  相似文献   
97.
The past 30 years have witnessed a major paradigm shift in brain tumor research with the development of a wide variety of molecular  相似文献   
98.
99.
The present report describes psychobiological studies of behavior around the time of birth. An adaptive, ecological perspective is presented in which stimulation of the fetus and newborn is purported to instigate adaptive postpartum behavior. Studies describing the perinatal sensory environment are reviewed, with a consideration of emergent sensory function of the fetus. It is asserted that afferent input associated with parturition perturbs the fetus and neonate, producing a general arousal state that facilitates breathing, suckling, and early learning. The view developed herein is that perinatal sensory input induces and canalizes the newborn's behavior, thereby regulating adaptive postpartum function. Deviations in afferent input may alter ontogenetic trajectories and compromise developmental outcome by reducing availability of conditions necessary for adequate postpartum adaptation.  相似文献   
100.
Thirteen anaemic children on dialysis were assessed to determine the incidence of cardiac changes in end stage renal failure. Nine children had an increased cardiothoracic ratio on radiography. The electrocardiogram was abnormal in every case but no child had left ventricular hypertrophy as assessed by voltage criteria. However, left ventricular hypertrophy, often gross, was found on echocardiography in 12 children and affected the interventricular septum disproportionately. Cardiac index was increased in 10 patients as a result of an increased left ventricular stroke volume rather than heart rate. Left ventricular hypertrophy was significantly greater in those on treatment for hypertension and in those with the highest cardiac index. Abnormal diastolic ventricular function was found in 6/11 children. Children with end stage renal failure have significant cardiac abnormalities that are likely to contribute to the high cardiovascular mortality in this group. Anaemia and hypertension, or its treatment, probably contribute to these changes. Voltage criteria on electrocardiogram are of no value in detecting left ventricular hypertrophy. Echocardiography must be performed, with the results corrected for age and surface area, in order to detect and follow these abnormalities.  相似文献   
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