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561.
We have used advanced endourologic techniques in the treatment of an obstructed lower-pole calycocystostomy site. The unusual clinical course that led to this problem and the interventional treatment used are discussed.  相似文献   
562.
MacEwan  DW 《Radiology》1985,156(2):289-294
Diagnostic imaging policy for the one million people of Manitoba was reviewed. Four complete data collections of diagnostic imaging activity, physician claims, vital statistics, and disease incidence from existing registries were assembled. Mammography, Hodgkin disease, and regional enteritis were analyzed briefly. Studies of protocols for patient access to computed tomography, imaging in head injury, and actions by society indicated that new technology and procedures can be accommodated at manageable public expense. To overcome emerging problems, several initiatives have been considered, including a proposed Canadian Health Council to moderate policy, a personal health identification number to link information, and imaging investigation directed by radiologists.  相似文献   
563.
Gelfand  DW; Dale  WJ; Ott  DJ; Wu  WC; Kerr  RM; Munitz  HA; Chen  YM 《Radiology》1985,157(3):577-581
Potential radiologic findings of duodenitis were investigated in 272 patients, 157 with endoscopically diagnosed duodenitis and 115 endoscopically normal controls. The study assessed the value of four signs: folds more than 4 mm thick, mucosal nodules, bulbar deformity, and erosions. The most sensitive signs were thickened folds (72.0%) and nodularity (48.4%), while demonstration of erosions was the least sensitive (10.8%). Overall sensitivity (77.7%) approximated that for the radiologic diagnosis of peptic ulcer or esophagitis. Radiologic specificity (76.5%) was in the same range.  相似文献   
564.
565.
Safe splenoportography   总被引:2,自引:0,他引:2  
The records of 37 patients who had undergone splenoportography, including one group of 12 who were studied before 1976 and a second group of 25 who were studied after 1977, were reviewed. The primary difference was that in the second group, the tract in the spleen was occluded with absorbable gelatin sponge (Gelfoam) plugs as the needle was withdrawn. In addition, there were minor changes in technique, such as changes in the needle puncture angle and entry site. When the new technique was used, there was a significant decrease in the complications traditionally associated with splenoportography. This procedure is safe and deserves to be considered the procedure of choice in patients in whom precise anatomic information is needed preoperatively that cannot be obtained with noninvasive procedures such as ultrasound or magnetic resonance imaging.  相似文献   
566.
Thirty-two patients (64 hips) in whom avascular necrosis (AVN) of the femoral heads was highly suspected clinically were studied by magnetic resonance (MR) imaging, radionuclide bone scintigraphy, and conventional radiography. MR studies were positive for AVN in 37 hips, compared with 30 positive scintigraphic studies. In all cases in which scintigraphy and radiography were positive, MR imaging demonstrated decreased signal from the affected femoral heads, indicative of bone marrow disease. Imaging results were confirmed by biopsy or subsequent imaging appearances. In patients with negative initial scintigraphic and radiographic studies, the MR imaging criterion for a positive study was a moderately decreased bone marrow signal displaying segmental patterns within an otherwise normal-appearing femoral head on relatively T1-weighted images. In this series of high-risk patients, radionuclide scintigraphy had a sensitivity of 81%, compared with 100% for MR imaging. MR imaging should be the imaging modality of choice for early evaluation of bone marrow changes indicative of AVN.  相似文献   
567.
OBJECTIVE: Current models propose that the experience of pain includes both sensory and affective components. Our purpose was to use functional MR imaging to determine areas of the brain engaged by the affective dimension of pain. SUBJECTS AND METHODS: Twelve healthy adults underwent functional MR imaging using a gradient-echo echoplanar technique while a cold pressor test, consisting of cold and pain tasks, was applied first to one foot and then to the other. The cold task involved the application of cold water (14-20 degrees C) that was not at a painful level. For the pain task, the water temperature was then lowered to a painful temperature (8-14 degrees C) and subsequently to the pain threshold (3-8 degrees C). Images acquired at room temperature before the cold and pain tasks served as a baseline task. Composite maps of brain activation were generated by comparing the baseline task with the cold task and the cold task with the pain task. The significance of signal changes was estimated by randomization of individual activation maps. RESULTS: Cold-related activation (p < 0.01) was found in the postcentral gyrus bilaterally, laterally, and inferiorly to the primary motor-sensory area of the foot and at a site near the second somatosensory site. Activation also occurred in the frontal lobe (the bilateral middle frontal gyri and the right inferior frontal gyrus), the left anterior insula, the left thalamus, and the superior aspect of the anterior cingulate gyrus (seen at one slice location). Pain-related activation (p < 0.01) included the anterior cingulate gyrus (seen at four slice locations); the superior frontal gyrus, especially on the right; and the right cuneus. CONCLUSION: Compared with the basic sensory processing of pain, the affective dimension of pain activates a cortical network that includes the right superior frontal gyrus, the right cuneus, and a large area of the anterior cingulate gyrus.  相似文献   
568.
569.
颈内动脉注射血小板激活因子(PAF),再给伊文思蓝,可见脑实质染色程度加深,而颈内动脉只注射伊文思蓝,脑实质未见染色。而我们合成的新药SZ-1可剂量依赖性地抑制PAF诱导的脑实质伊文思蓝染色程度的加深。在体外培养的脑微血管平滑肌细胞上,PAF能显著刺激14C-花生四烯酸的释放,而SZ-1能剂量依赖性地抑制这种释放,提示PAF在脑内产生的损害除与其他因素相关外,还与其刺激花生四烯酸释放有密切关系,SZ-1对PAF引起的脑部损害有保护作用。  相似文献   
570.
部分回顾性临床研究观察到在营养液配方中添加特异的药理营养素可能降低术后并发症,缩短术后恢复时间,但仍缺乏较大样本、前瞻性、多中心、随机对照临床研究的证据.近年来,药理营养素在肿瘤患者综合治疗中可能发挥的作用逐渐受到重视.本研究前瞻性观察了静脉用鱼油脂肪乳剂对消化道肿瘤术后患者结局和免疫功能的影响.  相似文献   
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