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31.
The results of Kr-81m/Tc-99m ventilation-perfusion (VP) lung scintigraphy were correlated with the results of pulmonary angiography for 74 patients suspected of having pulmonary embolism (PE). Among patients having a diagnostic scan, the sensitivity and specificity of scintigraphy were 91% and 94%, respectively. Also, 157 consecutive cases of Kr-81m/Tc-99m VP lung scintigraphy were reviewed, and the frequency of an indeterminate scan was found to be 22%. A similar frequency was found for VP scintigraphy with xenon-133. Of eight patients who had indeterminate scans due to the presence of a single VP mismatch, four were demonstrated to have PE by angiography. Kr-81m is an excellent agent for VP scanning in cases of suspected PE, offering accuracy in diagnosis as well as favorable physical properties.  相似文献   
32.
Background Patients with prostate cancer with a pre-operative prostate-specific antigen (PSA) τ;15ng/ml who undergo radical retropubic prostatectomy (RRP) generally do not have a good outcome, yet may have organ-confined cancer and should be offered the option of surgery. Aim To assess the outcome of patients who underwent RRP with a pre-operative PSA ≥ 15ng/ml. Methods Thirty-four patients, mean pre-operative PSA: 25.46ng/ml (15.03–76.6) and mean Gleason score: 6.4 (5–9) were assessed. Results Two groups were identified. Group I: 41% (14/34) have no biochemical recurrence to mean follow up of 58 months (30–106). Mean PSA: 18.8ng/ml (15.03–25.84). Mean Gleason score: 6.1 (5–7). Clinical stage: T1c in 80%. No patient had seminal vesicle or lymph node involvement. Group II: 59% (20/34) have biochemical recurrence or died (3) from their disease to mean follow up of 66 months (36–98). Mean PSA: 28.9ng/ml (15.28–76.6). Mean Gleason score: 6.7 (5–9). Clinical stage: T1c in 25%. Eleven patients had seminal vesicle (8) involvement or positive lymph nodes (3) or both (2). Conclusion RRP seems feasible in patients whose pre-operative PSA is between 15 and 25ng/ml with stage T1c, Gleason score ≤ 7 and negative lymph node frozen section.  相似文献   
33.
Kapila  A; Chakeres  DW 《Radiology》1986,160(1):265-267
A new technique has been designed to improve myelography examinations of the entire lumbar spinal canal in patients with severe spinal stenosis using a single needle puncture. When a high-grade obstruction to the caudal flow of contrast material is encountered, the patient is placed in a flexed sitting position for 1 minute. This technique was performed in eight patients with severe lumbar spinal stenosis. It successfully helped depict the lower lumbosacral canal below an apparently complete block in four patients and resulted in improved visualization of the lower sac in four patients with partial block.  相似文献   
34.
Percutaneous nephrostolithotomy, which can require a double puncture, is presently the method of choice in our institution for the removal of renal stones. Patients that underwent this procedure were evaluated to identify the possible reasons for the double puncture. Of 200 patients evaluated, 14 needed a second tract. The three variables that determined whether a second puncture was needed, in order of importance, were number and size of the stones, with second tracts needed in patients with multiple stones and staghorn calculi; anatomical variations of the renal collecting system itself, with bifid systems the most significant anatomic variation; and the dexterity of the radiologist in performing the puncture and the ability of the urologist to extract the stone. Second tracts were needed more frequently in patients who presented with stones in both the lower and middle poles of the collecting systems.  相似文献   
35.
Experience with the Amplatz retrievable vena caval filter. Work in progress   总被引:1,自引:0,他引:1  
The Amplatz retrievable vena caval filter was designed in an attempt to decrease complications associated with the placement of Mobin-Uddin or Kimray-Greenfield filters. The design allows percutaneous retrieval, thus expanding application of the filter to situations requiring temporary prophylaxis against pulmonary embolism. Filters have been placed in 16 patients, nine (56%) for prophylactic purposes. All filters were easily inserted percutaneously. Complications occurred in three patients; these included complete thrombosis of the inferior vena cava below the filter, misplacement of one filter into the pericaval retroperitoneal tissue, and development of thrombus cranial to the filter. With the current introduction system, the possibility of filter misplacement has been essentially eliminated. No patient experienced symptoms suggestive of pulmonary embolism after filter insertion. One filter retrieval has been performed, with no complications.  相似文献   
36.
Gelfand  DW; Chen  YM; Ott  DJ 《Radiology》1987,164(2):333-337
A systems approach was employed to improve results of the single-contrast barium enema examination for detection of colonic polyps. Improvements were made in each of the following areas: radiographic-fluoroscopic equipment, fluoroscopic-television images, screen-film combinations, barium suspensions, examination techniques, imaging sequences, and quality controls. Radiologic-endoscopic correlation was undertaken for 137 colonic polyps seen endoscopically in 91 patients. The average age of the patients was 69 years. The sensitivity of the single-contrast examination for detection of all polyps was 80%. Polyps 5-9 mm in size were detected with 66% sensitivity, while 94% of polyps 10 mm or larger were detected. The results indicate that the sensitivity of a suitably performed single-contrast barium enema examination may approach that of the double-contrast study for the detection of colonic polyps, even in an elderly and infirm patient population.  相似文献   
37.
Regeneration of diabetic axons has delays in onset, rate and maturation. It is possible that microangiopathy of vasa nervorum, the vascular supply of the peripheral nerve, may render an unfavorable local environment for nerve regeneration. We examined local nerve blood flow proximal and distal to sciatic nerve transection in rats with long-term (8 month) experimental streptozotocin diabetes using laser Doppler flowmetry and microelectrode hydrogen clearance polarography. We then correlated these findings, using in vivo perfusion of an India ink preparation, by outlining the lumens of microvessels from unfixed nerve sections. There were no differences in baseline nerve blood flow between diabetic and nondiabetic uninjured nerves, and vessel number, density, and area were unaltered. After transection, there were greater rises in blood flow in proximal stumps of nondiabetic nerves than in diabetic animals associated with a higher number, density, and caliber of epineurial vessels. Hyperemia also developed in distal stumps of nondiabetic nerves but did not develop in diabetic nerves. In these stumps, diabetic rats had reduced vessel numbers and smaller mean endoneurial vessel areas. Failed or delayed upregulation of nerve blood flow after peripheral nerve injury in diabetes may create a relatively ischemic regenerative microenvironment.  相似文献   
38.
39.
关节部位Ⅲ度烧伤削痂植皮与切痂植皮的效果比较   总被引:3,自引:0,他引:3  
目的:Ⅲ度烧伤创面的处理临床上仍然以切痂植皮术治疗为主,由于切痂时切除了并未损伤的皮下脂肪组织,使其愈后外观变化明显。实验拟观察关节部位Ⅲ度烧伤削痂后于脂肪层移植大张自体中厚皮的疗效,并与切痂植皮进行比较。方法:①于2001-01/2007-06南昌大学第一附属医院烧伤科收治的关节Ⅲ度烧伤患者中抽取39例(45个关节)作为削痂组,同时抽取45例(共60个关节)作为切痂组。所有患者对治疗及实验方案均知情同意,且得到医院伦理道德委员会批准。②削痂组削痂植皮,保留正常皮下脂肪等组织。切痂组切痂植皮,切痂平面包括全层皮肤和皮下脂肪组织一并切除直至深筋膜层。削痂或切痂后植大张自体中厚皮。③创面修复后4 ̄6周观察两组患者的关节外观和关节活动功能;比较两组患者术后2周的植皮成活率和创面修复时间。结果:两组患者均进入结果分析。①两组患者烧伤关节创面修复后与对称的正常关节比较,削痂组外观变化不明显,周径缩小3.6%(P>0.05),功能好,关节活动度减少5.3%(P>0.05);切痂组外观变化明显,周径缩小23.4%(P<0.05),功能较差,关节活动度减少21.9%(P<0.05)。②两组患者术后2周植皮成活率和创面修复时间差异均无显著性意义(P>0.05)。结论:脂肪层移植大张自体中厚皮于Ⅲ度烧伤削痂后关节部位,能够维护肢体的美观,保护关节功能,疗效优于切痂植皮。  相似文献   
40.
预防治疗2型糖尿病药物分子作用靶点的相关研究与进展   总被引:1,自引:0,他引:1  
目的:综合分析2型糖尿病新药研究的分子靶点。资料来源:应用计算机检索Springer1990-01/2005-02和Pubmed2000-01/2005-08有关预防和治疗2型糖尿病药物的文献,检索词“diabetes,drug,target”,并限定文献语言种类为English。资料选择:对检索到的有关预防和治疗2型糖尿病药物的相关信息进行整理,筛选针对性强、影响因子较大、最近几年发表的论文。资料提炼:共检索到相关文献49篇,其中15篇符合要求,排除34篇。排除的文章中6篇是关于2型糖尿病的病理生理及生化方面的基础研究,其余为2型糖尿病预防和治疗效果方面的文献。资料综合:综合文献资料发现,以往研制的治疗糖尿病的药物或者因缺乏明确的分子靶点,或者因对疾病本身的病理反应不清楚,因而存在各种弊端。有关预防和治疗2型糖尿病和代谢综合征的分子靶点为抗糖尿病药物的研发展示了光明的前景,涉及的药物包括经典受体的小分子调节剂、酶作用靶点、蛋白质制剂和反义寡核苷酸等。结论:根据2型糖尿病和代谢综合征特异的病理反应机制作为筛选药物的分子基础是未来抗糖尿病药物研发的主攻方向。  相似文献   
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