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排序方式: 共有173条查询结果,搜索用时 0 毫秒
61.
Rotator cuff sonography: a reassessment   总被引:4,自引:0,他引:4  
Brandt  TD; Cardone  BW; Grant  TH; Post  M; Weiss  CA 《Radiology》1989,173(2):323-327
This study is both a retrospective and prospective evaluation of the clinical usefulness of shoulder sonography. Ninety-eight patients suspected of having rotator cuff tears underwent sonography of both shoulders. Sixty-two patients underwent double-contrast arthrography performed on the same day as sonography, and 38 patients underwent surgery after sonography. A comparison of the results from ultrasound and arthrography, using published diagnostic criteria, demonstrated a sensitivity of 75% and a specificity of 43% for detection of a rotator cuff tear. In this study, use of more restricted criteria, a subset of the published criteria, yielded a sensitivity of 68% and a specificity of 90%. A comparison of sonography with surgery, using this study's criteria, demonstrated a sensitivity of 57% and a specificity of 76%. This report shows that shoulder sonography is less reliable than previously reported and appears to have a very limited role in the evaluation of rotator cuff injuries.  相似文献   
62.
野花椒系芸香科植物(Zanthoxylum simulans Hance),其根皮有止痛及局麻作用。其水溶性生物碱有肌松作用,曾用于外科手术作为中麻辅助用药。常志青从中分离到加钖果宁[(—)edulinine,简称加钖碱,下同],并发现有镇痛及中枢抑制作用。本文进一步证明其镇痛作用及其作用机制与阿片受体有关。  相似文献   
63.
Equivocal mammographic findings: evaluation with spot compression   总被引:3,自引:1,他引:2  
Berkowitz  JE; Gatewood  OM; Gayler  BW 《Radiology》1989,171(2):369-371
Seventy-five spot compression views of equivocally suspicious lesions detected at routine mammographic examination of 72 women were reviewed in this retrospective study. Sixty-five of the 75 lesions appeared less suspicious on spot compression views, two did not change, and eight appeared more suspicious. Biopsy findings confirmed that the eight more suspicious lesions were cancer. The adjunctive use of spot compression helped characterize equivocal findings seen on routine mammographic views and improved the accuracy of mammographic interpretation.  相似文献   
64.
Paranasal sinuses: CT imaging requirements for endoscopic surgery   总被引:17,自引:0,他引:17  
Recent advances in the understanding of mucociliary activity and the pathophysiology of the nasal cavity and paranasal sinuses have revolutionized the surgical management of chronic and/or recurrent sinusitis. Meticulous radiographic delineation of the small structures in this region, coupled with endoscopic evaluation, provides detailed preoperative information regarding morphology and pathology. This information has led to more focused endoscopic surgical procedures, which have dramatically reduced patient morbidity. As a consequence, there is now worldwide interest among otolaryngologists in the radiologic definition of paranasal regional anatomy. For effective interactions between radiologist and otolaryngologist, the former must be prepared to render interpretations that address these "microanatomic" locales. This communication is directed at familiarizing the radiologist with these observations and concepts, considering both normal and disturbed anatomy with their attendant pathophysiologic and therapeutic implications.  相似文献   
65.
目的:研究人工唾液对银汞合金和玻璃离子水门汀2种口腔充填材料承载能力的影响,比较不同材料受环境影响的特征.方法:制作10 mm直径、2 mm厚度的银汞合金和玻璃离子水门汀圆盘形试件各80个,各自随机分成8组,分别放入干燥容器和盛有人工唾液的容器内置于37℃恒温箱中保存1、7、30、90 d,置于30%玻璃纤维加强尼龙6,6基底上以20 mm直径不锈钢球加载进行赫兹压痕试验,记录初始断裂载荷值并进行统计分析.结果:在90 d观察期内,银汞合金的断裂载荷值在空气中从(641.09±121.16)N增加到(775.08±105.37)N(P<0.05),在人工唾液中则从(680.09±115.90)N减少到(620.00±62.17)N,但无统计学差异(P>0.05).玻璃离子水门汀的断裂载荷值在空气中波动于(391.18±83.10)~(456.25±74.14)N范围,无统计学差异(P>0.05);在人工唾液中则从(388.70±66.78)N显著减少到(308.45±53.49)N(P<0.05).经过不同的时间段后,2种材料最终均表现为在人工唾液中的断裂载荷值低于在空气中的值.结论:长期人工唾液浸泡对口腔充填材料的承载能力有明显负性影响;不同材料对储存介质的影响反应不同.  相似文献   
66.
PURPOSE: We evaluated the efficacy and safety of a mentor-initiated program for laparoscopic radical prostatectomy by analyzing its effect on the learning curve. PATIENTS AND METHODS: The mentor performed 16 procedures (group I) and the trainee, assisted by the mentor, 12 (group II). The next 16 procedures were performed by the trainee without the mentor (group III). The patient groups were comparable in terms of age, serum prostate specific antigen concentration, Gleason score, and clinical stage. The operating time, blood loss, complications, and outcomes were evaluated. Statistical analysis was performed using ANOVA with the multiple-comparisons test with Bonferroni correction and the Kruskal-Wallis test, when appropriate. RESULTS: There was a statistical difference in the mean operating time in groups I and II (271 and 381 minutes, respectively; P < 0.001) and in groups I and III (271 and 386 minutes, respectively; P < 0.001), but the difference between groups II and III was not significant (P > 0.05). The mean estimated blood loss was similar in all groups (362, 395, and 434 mL, respectively; P = 0.86). The mean postoperative day 1 decrease in hemoglobin was similar in the three groups (0.65, 0.66, and 0.66 mg/dL, respectively; P = 1.00). No patient required open conversion. Postoperative complication rates were the same in groups I and III (6.25%). The mean catheterization time was longer in group III (6, 7, and 12 days; P < 0.001). The mean hospital stays (9, 8, and 8 days; P = 0.28) were similar. Stage pT(3)-pT(4a) disease was found in 75%, 41.6%, and 75% of the specimens in groups I to III, respectively. There was no statistical difference in positive-margin rates in the three groups (43.8%, 33.3%, and 37.5%; P = 0.85). CONCLUSIONS: A mentored program allows safe introduction of laparoscopic radical prostatectomy into surgical practice. Nevertheless, during the learning curve, longer operating and catheterization times have to be expected.  相似文献   
67.
Cryotherapy is a curative treatment option for patients with small (<4 cm) renal-cell cancers. For the followup of ablated lesions, imaging is the only available method, but the best tool has not yet been determined. The method selected should be able to determine the presence or absence of perfusion in the area and measure the lesion. Usually, contrast-enhanced CT or MRI is used. The accompanying video shows cryotherapy treatment along with contrast-enhanced ultrasound investigations before and afterward. We used a Siemens Acuson Sequoia device with contrast pulse sequence imaging and Sonovue (Bracco) as the contrast agent. The lesion could be identified and measured easily. Because this method enables selective detection of contrast, the presence and absence of perfusion can be determined objectively.  相似文献   
68.
Patients with partial seizures: evaluation by MR, CT, and PET imaging   总被引:9,自引:0,他引:9  
Fifty patients who experienced partial seizures were imaged with computed tomography (CT) and magnetic resonance imaging (MR); 14 of these also had imaging studies of local cerebral glucose metabolism with positron emission tomography (PET). Thirteen patients with attenuation abnormalities on CT scans also had abnormal signals on MR images; ten other patients had MR-image signal abnormalities but normal CT scans. In all seven patients undergoing PET who had MR-signal and sometimes also CT-attenuation abnormalities, areas of metabolic asymmetry were present. Positive PET scans were also seen in three patients with no evidence of abnormality on CT and MR studies. Focal cerebral substance loss on CT and MR studies, present in 21 patients, did not correlate well with electroencephalographic findings. MR is utilized as the initial imaging procedure in patients with partial seizures because it is more readily available and less invasive than PET and more sensitive than CT scanning.  相似文献   
69.
70.
AimsTo review the current status of cryoablation of small renal masses and to preliminary report our experience at the AMC.Material and methodsA bibliographic search was conducted (PubMed/Medline/Embase) and the most important series were analyzed. Our series includes 13 patients with a solitary small renal mass treated by Laparoscopic assisted Cryoblation with fine cryoprobes (1,5 cm diameter). Postoperative follow-up was done by means of CT and/or MRI every three months during the first year and every 6 months during the second year.ResultsThere are no randomized trials comparing Cryoblation of renal masses (<4 cm diameter) with either radical surgery or partial nephrectomy but only case series. Complication rate is low as it is the recurrence or persistence rate in most of the series but one referring to radiologically guided Cryoablation (8%). The maximal diameter of the masses treated in our series were 3,2 cm. Tumors were approached retro or transperitoneally depending on their localization in the kidney. Average surgical time were 208 minutes (108-379) and average time of exposition to temperatures lower than –20ºC in the tumor periphery was 10 minutes. AT a mean follow-up of 8 months no tumoral recurrence were objectivated.ConclusionsCryoablation of small renal masses may be an acceptable alternative of treatment although mean follow-up is still short in all the series.  相似文献   
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