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31.
FLORA UKOLI USIFO OSIME FOLASADE AKEREYENI OSAZUWA OKUNZUWA RICK KITTLES LUCILE ADAMS-CAMPBELL 《International journal of urology》2003,10(6):315-322
BACKGROUND: Recent hospital and cancer registry data show increasing prostate cancer incidence in Nigeria, which was previously regarded as a low incidence region. This study investigates the prevalence of prostate cancer risk in a previously unscreened cohort of rural Nigerians. METHODS: Rural Nigerian men, 40 years and older, were screened by serum prostate-specific antigen (PSA) and digital rectal examination (DRE) and those with PSA >/= 4 ng/mL and/or abnormal DRE were referred for prostate biopsy. RESULTS: Of 200 consecutive men invited, 151 (75.5%) presented for screening, the mean age was 56.45 + 15.1 and 95 (61.6%) were >/= 50 years of age. Of the 140 who consented to a blood test, PSA correlated with age (r = 0.3, P < 0.01), 14 (10.0%) had abnormal PSA >/= 4 ng/mL, increasing from 3 (3.6%) in men < 60 years to 4 (50%) in men >/= 80 years. The rate was 13 (15.7%) for men >/= 50 years and there was no evidence of increased incidence of prostatitis in the community. Mean (median) PSA in ng/mL increased from 1.17 (0.60) in the youngest to 13.75 (4.45) in the oldest cohort. Of those who accepted DRE, 38 (29.0%) had an enlarged prostate, including two who had nodular prostate, one-third with symptoms, increasing from 4 (5.4%) in those < 50 years to 6 (75.0%) in men >/= 80 years. The proportion of men with PSA >/= 4 ng/mL among those with enlarged vs normal prostate is 27.0 to 3.4%, P < 0.001, and the pattern was similar for men >/= 60 years and those < 60 years of age. The 40 (32.0%) men referred for prostate biopsy defaulted mainly because they did not fully understand the need for further investigation because they were symptom free or afraid of the possible side-effects of the procedure or diagnosis of cancer. CONCLUSION: The proportion of men with PSA >/= 4 ng/mL is comparable to that of previously unscreened populations with high incidence of prostate cancer such as African-American men. A larger study is required to confirm these findings and intensify efforts to determine the prostate cancer detection rate by biopsy in this population. A prostate cancer awareness and education campaign will be useful in this community. 相似文献
32.
Didier A. Chartier 《L'évolution Psychiatrique》2003,68(2):211-232
The state of “nodding off” which the psychoanalyst may experience during therapy is a phenomenon that requires further investigation into its nature, causes, and effects. Even if it occurs only sporadically and is a physiological necessity, it nevertheless has a certain effect and can present certain advantages. This introduction of resistance in the form of sleep can sometimes provide an opportunity in the development of sensorimotor functions for the patient to verbalize his experience, and in any case this phenomenon should not be taken lightly. Recourse to current knowledge regarding sleep can improve our understanding of this phenomenon, and we should be prepared to take the risk of examining psychoanalysis on the basis of a non-analytical approach, i.e. primarily psychobiological and cognitive. This also permits a link to be made between the psychoanalyst’s therapeutic activity and the contextual phenomena which influence cerebral activity and its level of vigilance which is expressed by specific types of verbalization. The pertinence of this risk-taking should also be examined, and a distinction made between physiologically necessary somnolence and other causes. It appears that in the present context, the induction of a state of somnolence is caused by the narcissistic characteristics of a transferential relation that is in the process of development; that is to say, the “positive aspects’’ of narcissism, which are an integral part of psychic growth. However, we should also bear in mind that these narcissistic characteristics can also be expressed in the form of resistance. 相似文献
33.
Karl Lehner M.D. Maximilian Reiser Ulrich Gebhardt Andreas Heuck Jürgen Schaff 《Cardiovascular and interventional radiology》1987,10(2):71-74
In contrast to conventional film angiography, the perfusion pattern of hepatic arterial chemotherapy was consistently visualized
by DSA in 40 patients with implanted Infusaid pump or Port-A devices. Incomplete perfusion of a liver region by the cytotoxic
agent was recognized by DSA as accurately as by nuclide scintigraphy. Furthermore, DSA appeared to be more sensitive in determining
aberrantly perfused extrahepatic regions; this was especially true when there was a nonligated right hepatic artery. Specific
details of vascular lesions and associated complicating events also could be satisfactorily analyzed by DSA only. 相似文献
34.
大脑中动脉狭窄的TCD与DSA检查比较研究 总被引:1,自引:0,他引:1
目的 :通过大脑中动脉狭窄的TCD检查与DSA检查方法比较 ,为临床提供方便可靠的检查方法。方法 :对经TCD检查确诊为大脑中动脉狭窄 6 0例做DSA检查 ,对两种检查结果进行比较分析。结果 :经TCD确诊为大脑中动脉狭窄病例 ,病变侧狭窄处的血流速度(Vm)均明显高于健侧一倍以上 ,在动脉硬化性狭窄中多伴有“海鸥鸣”或“铁锅炒沙”样杂音 ,且频谱形态呈圆钝或脉动指数值增高的阻力波形。该 6 0例在DSA的检查中均出现不同部位的不同狭窄。结论 :TCD检查具有快速方便、安全、经济、确诊率高的优点 ,可作为脑血管病首选检查手段 相似文献
35.
三维时间飞跃法MR血管造影血液铸型诊断颈内动脉系颅内动脉瘤的优势 总被引:5,自引:0,他引:5
目的 与多层面螺旋CT三维血管造影 (MS 3D CTA)和DSA比较 ,探讨三维时间飞跃法MR血管造影 (threedimensionaltimeofflightMRA ,3DTOFMRA)图像后处理血液铸型技术 (fly around)诊断颈内动脉系颅内动脉瘤的优势和临床应用价值。方法 18名疑诊颈内动脉系颅内动脉瘤病人 ,男 4例 ,女 14例 ;年龄 17~ 76岁 ,平均 4 9 8岁 ;其中蛛网膜下腔出血 (SAH) 14例、动眼神经麻痹 4例。所有病人均接受 3DTOFMRA和MS 3D CTA检查 ,17名接受DSA检查 ,确诊后均经手术治疗。 3DTOFMRA用Toshiba 1 5T超导型MR系统VISART的 3D TOF序列采集原始数据。其参数为 :TR 30ms,TE 6 8ms ,反转角 2 0° ,视野 (FOV) 17cm× 19cm ,矩阵 16 0× 2 5 6 ,采集层块厚度 5 0~ 6 0mm ,层厚 1 2mm ;原始图像后处理方法采用最大密度投影 (MIP)和血液铸型。MS 3D CTA用Toshiba多层螺旋CT Aquilion采集原始数据。其参数为 :扫描速度 0 5s/r,层厚 1 0mm ,螺距 3 5 ;用高压注射器静脉注射非离子型对比剂 ,注射剂量 2 0ml/kg体重 ,注射流率 4 0~ 5 0ml/s ,延迟时间 15~ 18s ;原始图像后处理方法同 3DTOFMRA。图像后处理工作站均用SGIO2 ,后处理软件为Alatoview ,版本 1 4 2。DSA用SiemensMulti StartOT经股动脉插管行常规脑动脉四血管造影 相似文献
36.
改良上颌平面导板矫正青少年深覆颌的临床观察 总被引:1,自引:0,他引:1
目的观察改良上颌平面导致矫正青少年深覆颌的效果。方法制作上颌平面导板,下颌双侧尖牙与其接触,后牙抬高3.0 mm。分为昼夜戴用导板及仅夜间戴用导板两组,观察疗效。结果深覆颌总矫正率72.2%,昼夜戴用该改良上颌平面导板组的深覆颌矫正率100%。结论改良上颌平面导板制作简单,戴用方便,效果明显。 相似文献
37.
目的:研究VitapanClassical比色板各比色片中1/3部分的色度值的分布规律,以利于提高临床上的比色准确率。方法:在自然光线下用数码相机对VitapanClassical比色板进行摄影,将拍摄结果输入计算机,经Photoshop7.0软件处理后,记录各比色片中1/3部分的亮度和RGB值。结果:各比色片中1/3部分的亮度和R、G、B值是不同的。结论:数码摄影能够较真实地再现VitapanClassical比色片的颜色,可以作为临床比色方法和烤瓷材料颜色选择的补充。 相似文献
38.
基于组合不变量配准的数字减影算法 总被引:2,自引:1,他引:1
在现代医学中,DSA是X光片血管可视化技术的重要组成部分之一,在DSA中图像配准对消除运动伪影起着关键作用。运用一种基于组合不变量的相似度测量的模板匹配和弹性TPS算法配准减影方法,并根据实际情况有所改进。经过试验证明这种方法可以自动并有效地去除运动伪影,其速度和血管图像质量均比较理想。 相似文献
39.
股骨颈骨折后选择性血管造影评价股骨头血液循环 总被引:13,自引:0,他引:13
目的 探讨选择性血管造影检查对评价股骨颈骨折后早期股骨头血液循环损伤及影响因素的价值。方法采用选择性旋股动脉及支持带动脉造影(DSA),对9例2~23天内单侧股骨颈骨折患者血管损伤和血液循环改变进行评价。结果髋关节囊内出血2例,骨内出血4例,下、后支持带动脉损伤和血管移位各3例。患髋牵引时,除外下支持带动脉,其他支持带动脉无显影或仅显示起始部主干,相应股骨头颈部几无灌注成像,静脉显影延迟;髋关节维持伸直内旋位或囊内注入生理盐水后造影,所有支持带动脉无明确显影或仅显示其主干,股骨头颈部无灌注、染色,静脉显影延迟。结论选择性旋股内、外侧动脉DSA技术是一项准确评价股骨颈骨折后股骨头血液循环损伤及影响因素的微创性检查方法;股骨头血液循环受髋关节体位、囊内压和牵引等因素影响;牵引可导致或加重股骨颈骨折后股骨头缺血。 相似文献
40.
David P. Faxon David Holmes Geoffrey Hartzler Spencer B. King Gerald Dorros 《Catheterization and cardiovascular interventions》1992,25(1):1-3
At present, the majority of cardiac catheterization laboratories acquire and store hemo-dynamic data in analog form. To examine the possibility of performing complex analysis of digital data during the catheterization procedure, we examined whether virtual realtime digital (fast Fourier) analysis improves the accuracy of clinical data. We compared digital filtering of fluid manometry during right heart catheterization with 10-Hz and 250-Hz analog filters. Using the simultaneously acquired micromanometry as the “gold standard,” we found that analog filtering is associated with a greater error and time delay than digital filtering. This study demonstrates that digital hemodynamic data analysis performed during cardiac catheterization can improve the quality of data obtained during right heart catheterization, with the results available within seconds. More extensive use of computers in the cardiac catheterization laboratory may be useful for both clinical and research purposes. © 1992 Wiley-Liss, Inc. 相似文献