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991.
Cerebellopontine angle-petromastoid mass lesions: comparative study of diagnosis with MR imaging and CT 总被引:1,自引:0,他引:1
Capabilities of computed tomography (CT) and magnetic resonance (MR) imaging in the diagnosis of cerebellopontine angle-petromastoid (CPA-PM) lesions were compared in 75 patients. CT and MR demonstrated 95.8% and 98.7% of the lesions, respectively. MR was often more helpful for characterization of neuromas, epidermoid cysts, exophytic gliomas, and vascular lesions, while CT was usually more informative for meningiomas, metastases, and tympanomastoid cholesteatomas. A specific diagnosis could be made with MR for most types of lesions through use of relaxation parameters and characteristic morphologic changes. Size, shape, location, and contour of the lesions, however, were generally more helpful for differential diagnosis than relaxation times. With the exception of metastatic lesions, cholesteatomas, and some meningiomas, MR was usually more helpful than CT in defining the full extent of the lesions and their relationships to contiguous structures. MR, because of its high accuracy in lesion detection, characterization, and localization, is a suitable primary diagnostic modality for evaluating patients with suspected CPA-PM lesions. 相似文献
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995.
Selective uptake of [3H]arachidonic acid into the dense tubular system of human platelets 总被引:1,自引:0,他引:1
We have used quantitative electron microscopic autoradiography to characterize the subcellular distribution of arachidonoyl phospholipids following brief (5 minutes) exposure of unstimulated human platelets to [3H]arachidonic acid. Labeled arachidonate was taken up rapidly and incorporated into phospholipids. Phospholipid radioactivity was preserved and spatially fixed during tissue processing for electron microscopy. Analysis of autoradiographs showed that following a brief exposure to 750 nmol/L [3H]arachidonate, there is selective labeling of an internal membrane compartment composed of the dense tubular system and the open canalicular system. The plasma membrane, platelet granules, and nonmembranous cytoplasm were not labeled. Since the open canalicular system is continuous with the plasma membrane and since phospholipids in continuous membranes are freely diffusible, our observations indicate that [3H]arachidonate was incorporated into phospholipids within the dense tubular system and not the open canalicular system. Thus, the dense tubular system, known to contain cyclooxygenase activity, incorporates arachidonate selectively following brief exposure to this fatty acid, presumably to concentrate it in proximity to enzymes for icosanoid synthesis. 相似文献
996.
CM. Giles T. Gedde-Dahl Jr. E.B. Robson E. Thorsby B. Olaisen A. Arnason F. Kissmeyer-Nielsen I. Schreuder 《Tissue antigens》1976,8(2):143-149
In 19 families with 97 children the segregation of Rga (Rodgers) was found to be compatible with Mendelian inheritance and five backcross and 14 intercross families were found among HLA and Bf typed families. Close linkage (lods + 17.82) without recombination was found between Rg and the HLA region, with a direct count of 96 nonrecombinant meioses for Rg-HLA-B. Kg- was strongly associated with HLA-B8 (29 of 30 haplotypes) and probably associated with Bw40, but did occur on other HLA-B haplotypes. By inference.Rg- is negatively associated with Ch- (Chido). The Rg- Ch- haplotype has not been observed. Rg3 and Cha may or may not be coded for by different sites of the same cistron closely linked to HLA-B:C and cannot as yet be excluded from being parts of B or C. 相似文献
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998.
A new catheter suitable for selective angiography, embolization, and controlled infusion of chemotherapeutic agents is described. The catheter is made from a composite construction of polyethylene; it is graded in shaft thickness and outer diameter from a 2.7-F tip to a 3-F (1.0-mm) proximal section. Use of the catheter with a 0.018-inch or smaller steerable guide wire facilitates placement of the catheter in distal tortuous vessels. The catheter enabled successful completion of 20 of the 22 intracranial and extracranial intervention procedures (11 patients) in which it was used. 相似文献
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1000.
Bladder injury in blunt pelvic trauma 总被引:2,自引:0,他引:2
Clinical and radiologic findings in 97 patients with bladder injury secondary to blunt pelvic trauma were reviewed. Fifty-five patients had extraperitoneal bladder rupture; 35, intraperitoneal rupture; two, interstitial bladder injury; and five, combined intraperitoneal and extraperitoneal bladder rupture. Of the 61 of 97 patients with film studies available for review, two patients with surgically proved intraperitoneal rupture had false-negative cystograms. In two other cases of intraperitoneal rupture, the diagnosis was established with cystography but was not demonstrated with urography. All cases of extraperitoneal rupture were demonstrated cystographically; in 15 cases in this group, the injury was complex, with extravasation of contrast material beyond the confines of the perivesical space. In two additional patients, incomplete bladder injury termed "interstitial bladder rupture" was identified. A classification of bladder injury based on cystographic patterns of extravasation is proposed. 相似文献