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991.
Acute mesenteric ischemia: diagnosis with contrast-enhanced CT   总被引:34,自引:1,他引:33  
  相似文献   
992.
From October 1973 through August 1974, 335 genitourinary tract specimens from patients with urethritis were inoculated into McCoy's cell cultures for the diagnosis of Chlamydia infections. Of the 45 Chlamydia isolates, 42 were recovered when glass vials rather than plastic microtiter plates were used as cell culture vessels. Herpes simplex virus was isolated 15 times. Bacterial overgrowth occurred 42 times; however, in 20 specimens the contamination was not apparent until after the first subculture. This is the first report of the frequency of Chlamydia infections in patients with urethritis in the Midwest and indicates that these organisms have a significant etiologic role in nongonococcal urethritis in this community.  相似文献   
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The urinary bladder, obliterated umbilical arteries, and inferior epigastric vessels located within the extraperitoneal space of the anterior abdominal wall indent the anterior parietal peritoneum, forming intraperitoneal paravesical fossae. These are the supravesical space and the medial and lateral inguinal fossae. More posteriorly, the peritoneum covering the bladder is reflected onto the rectum to form the rectovesical space, which is divided by the uterus into an anterior vesicouterine recess and a posterior rectouterine pouch, or cul-de-sac. The cul-de-sac is continuous with the pararectal and ovarian fossae and is bounded posterolaterally by the rectouterine (sacrogenital) folds. These peritoneal compartments form a large potential space for the accumulation of ascites and are separated from the equally large extraperitoneal paravesical spaces by only a thin layer of peritoneum or peritoneum and umbilicovesical fascia. The computed tomographic scans of 100 patients with ascites were reviewed, with particular attention to the differentiation between intraperitoneal and extraperitoneal paravesical collections. The scans of intraperitoneal collections were found to have certain characteristic appearances, including inferior displacement of the distended urinary bladder, visualization of the umbilical folds, and preservation of the preperitoneal fat.  相似文献   
996.
Choroidal melanomas: correlation of NMR spectroscopy and MR imaging   总被引:4,自引:0,他引:4  
Six freshly enucleated, unfixed human eyes with choroidal melanomas were imaged on a 1.4-T superconducting magnetic resonance (MR) imaging system. Immediately thereafter the eyes were sectioned, and tumor samples were removed for study on a variable-field (0.19-1.4 T) nuclear MR spectroscopy unit. Shorter T1 and T2 relaxation times were observed in those tumors with the greater concentrations of melanin. This is believed to result from the paramagnetic effect of radicals known to exist in melanin. High magnetic field MR imaging can enable one to distinguish between pigmented melanomas; proteinaceous effusions; fresh and subacute hematomas; and nonmelanotic tumors, including amelanotic melanomas; but may not enable melanotic melanoma to be distinguished from fat or amelanotic melanoma from other nonpigmented tumors.  相似文献   
997.
Hydroxyapatite deposition disease   总被引:2,自引:0,他引:2  
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998.
Scintigraphic assessment of bone islands   总被引:1,自引:0,他引:1  
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1000.
Spinal cord central echo complex: histoanatomic correlation   总被引:1,自引:0,他引:1  
Nelson  MD  Jr; Sedler  JA; Gilles  FH 《Radiology》1989,170(2):479-481
Real-time sonography consistently demonstrates an echo complex centrally located in the spinal cord. This echogenic focus is currently attributed to the central canal. The authors sought the source of this central echo with ultrasound (US) and histoanatomic study of both fresh and fixed cadaver spinal cords. Correlative transverse sections of the spinal cord were stained with hematoxylin-eosin and Luxol fast blue for cells and myelin and with Holzer stain for glial fibrils. The central echo complex is produced by the interface between the myelinated ventral white commissure and the central end of the anterior median fissure. Variations in the shape of the central complex seem to reflect varying degrees of flaring of the central end of the anterior median fissure. The inconstant residual central canal and islands of residual ependymal cells are clearly not the source of the central echo complex.  相似文献   
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