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Immunobiology of human gliomas   总被引:5,自引:0,他引:5  
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Dural sinus thrombosis: study using intermediate field strength MR imaging   总被引:1,自引:0,他引:1  
The magnetic resonance (MR) images of six patients with thrombosis of a dural sinus were reviewed. The diagnosis had been verified by computed tomographic scans in three patients and arteriograms in two; in the sixth patient, only MR imaging was used to confirm the clinical syndrome. In all patients, high-intensity signal was seen from the thrombus within the affected dural sinus on all echoes. This persistent signal intensity allowed intravascular clot to be distinguished from normal causes of increased signal such as flow-related enhancement (entry phenomenon) and even-echo rephasing. MR imaging demonstrated the cause of the thrombosis in three patients: two were secondary to adjacent tumors, and one was secondary to unsuspected mastoiditis. Complications such as infarction were also demonstrated. Using MR imaging, one can easily and safely diagnose thrombosis of a dural sinus. MR should be the imaging method of choice in patients suspected of having thrombosis of a dural sinus.  相似文献   
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Three methods of treating chalazia were compared in a controlled trial. Group A (conservative therapy of warm soaks and lid hygiene) consisted of six patients with seven chalazia. Group B (intralesional adrenocorticosteroid injection) had five patients with five chalazia. Group C (conservative therapy with intralesional steroid injection) included nine patients with ten chalazia. Success rates after six weeks of follow-up were: Group A: 3 of 7 (43%), Group B: 4 of 5 (80%), and Group C: 9 of 10 (90%). Intralesional steroid injection with or without concurrent conservative therapy was more effective than conservative management alone.  相似文献   
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We used arthrotomography to study the glenoid labrum in 114 patients. Sixty-nine of the patients had anatomic instability of the shoulder (including recurrent dislocation and subluxation of the shoulder), and 45 patients had functional instability of the shoulder (denoted by chronic pain, clicking of the joint, and the sensation that an unstable condition exists without the objective signs of it). Labral tears were revealed arthrotomographically in 86% of the patients with anatomic instability, while only 40% of the patients with functional instability had labral abnormalities, and these were primarily of minor severity. Fifty-six patients (44 of whom had anatomic instability; 12, functional instability) required surgery. The surgical findings were correlated with the arthrotomographic findings, and no false-positive results were revealed. However, arthrotomography demonstrated only part of the pathologic condition of two patients. These results confirm that there is a strong correlation between labral pathologic conditions and anatomic instability of the shoulder. Arthrotomographic studies have a great impact on the selection of therapy in cases of both anatomic and functional instability of the shoulder.  相似文献   
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mRNA for the suppressive epitope of p15E was found to be present in 24 of 30 samples of human colorectal cancer and in all four specimens of gastric cancer. mRNA for p15E was seldom seen in nonmalignant colonic or gastric mucosa but, when present, was associated with inflammatory or pre-malignant conditions of the digestive tract. Synthetic peptides derived from the conserved p15E sequence were found to suppress some aspects of the immune response implicated in anti-tumour activity. These data suggest that a p15E-related material with immunomodulatory properties is elaborated within human tumours, either by the tumour itself or as a normal component of the endogenous anti-tumour reaction.  相似文献   
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Agonist-evoked rises in [Ca2+]i were recorded from single bovine aortic endothelial cells in the middle of confluent monolayers by dual-wavelength microspectrofluorimetry. Low doses of ATP (1-5 microM) induced a transient rise in [Ca2+]i followed by a maintained plateau phase upon which were superimposed irregular fluctuations in [Ca2+]i. The mechanism underlying these fluctuations is not known. Addition of the phorbol ester, phorbol 12-myristate 13-acetate (PMA), to single cells displaying ATP-induced fluctuations reduced the amplitude and frequency of these fluctuations but the maintained plateau phase was unaffected. Elevation of intracellular cAMP by activation of adenylate cyclase with forskolin, or application of dibutyryl cAMP did not affect the ATP-induced fluctuations. These results suggest a possible role for the diacylglycerol limb of the phosphoinositide hydrolysis pathway, via activation of protein kinase C, but not cAMP, in the mechanism responsible for generating ATP-induced fluctuations in [Ca2+]i.  相似文献   
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