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61.
A retrospective study of 100 cerebral computed tomography scans interpreted as displaying subarachnoid hemorrhage was undertaken to determine the frequency of blood in the interpeduncular fossa as a useful radiographic sign. The results indicate that the interpeduncular fossa sign is second only to blood in the Sylvian fissure-circular sulcus area as a reliable indicator of subarachnoid hemorrhage on CT scans. 相似文献
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Fleischer AC; Dudley BS; Entman SS; Baxter JW; Kalemeris GC; James AE Jr 《Radiology》1987,162(2):307-310
The depth of myometrial invasion by endometrial carcinoma was evaluated using real-time sonography (US) in 20 patients with histologically proved adenocarcinoma of the endometrium. In 14 of 20 (70%) cases, US-based estimation of the depth of myometrial invasion was within 10% of the actual measurement in the gross specimen. The US-based estimation of tumor invasion was low in seven patients, high in four patients, and agreed with pathologic findings (+/- 5%) in nine patients. In four patients with polypoid intraluminal extension of tumor, a deeply invasive tumor was suspected on US but was not found on pathologic examination. In 12 superficially invasive tumors, the continuity of the demarcating subendometrial halo was intact in nine and incomplete in three. In six patients with deeply invasive tumors, this zone was partially disrupted in four, totally disrupted in one, and intact in one. Errors of estimation of the depth of myometrial invasion on US most frequently occurred when a tumor had a significant intraluminal polypoid extension. Demonstration of a subendometrial halo usually indicated superficial invasion, whereas the absence of a halo was frequently associated with deep invasion. 相似文献
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SMIALOWICZ RALPH J.; RIDDLE MARIE M.; ROGERS RONALD R.; COPELAND CAREY B.; LUEBKE ROBERT W.; ANDREWS DEBORA L. 《Toxicological sciences》1991,17(4):771-781
Evaluation of the Immunotoxicity of Orally Administered 2-MethoxyaceticAcid in Fischer 344 Rats. SMIALOWICZ, R. J., RIDDLE, M. M.,ROGERS, R. R., COPELAND, C. B., LUEBKE, R. W., AND ANDREWS,D. L. (1991). Fundam. Appl. Toxicol. 17, 771781. We previouslydemonstrated that the glycol ether 2-methoxyethanol (ME) isimmunotoxic in the rat. In this study, the immunotoxicity of2-methoxyacetic acid (MAA), the principal metabolite of ME,was evaluated in adult male Fischer 344 rats. Rats were dosedby gavage with MAA on 10 consecutive days at dosages rangingfrom 50 to 200 mg/kg/day. Thymic involution, in the absenceof body weight loss, was observed at 100 and 200 mg/kg/day MAA.Lymphoproliferative responses to the mitogens concanavalin A,phytohemagglutinin, and pokeweed mitogen were also reduced atthese dosages. The in vitro generated cytotoxic T lymphocyteresponse was reduced at 200 mg/kg/day MAA. The mixed lymphocytereaction and natural killer cell activity were unaffected byexposure to MAA. Enumeration of splenic lymphocyte populationsrevealed a reduction in the percentage of W3/25-positive cellsat 100 and 150 mg/kg/day and an increase in the percentage of0X39-positive cells at 200 mg/kg/day; however, no changes inthe absolute number of either of these subsets were observed.The plaque forming cell (PFC) response to trinitropheny-lipopolysaccharide(TNP-LPS) was suppressed at 50-200 mg/kg/day MAA, while thePFC response to sheep red blood cells (SRBQ was elevated at50 mg/kg/day. Immunization of rats with TNP-LPS or SRBC followedby oral exposure to MAA at 4 and 28 hr postimmunization resultedin the suppression of the PFC response to TNP-LPS and SRBC atdosages of 100 and 200 mg/kg and 200 and 400 mg/kg, respectively.Equal suppression of the PFC response to TNP-LPS was achievedat equimolar concentrations of ME and MAA. The effects of MAAon the immune system of the rat presented here are very similarto results reported from this lab for ME-induced immune alterations.These results, along with results of experiments in which ME-inducedsuppression of the PFC response to TNP-LPS was reversed by 4-methylpyrazole,an inhibitor of the oxidation of ME to MAA by alcohol dehydrogenase,indicate that MAA is the proximate immunotoxicant followingexposure to the glycol ether 2-methoxyethanol. 相似文献
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Insertion of a screw biopsy stylet into a thin-walled biopsy needle greatly enhances detection of the needle during ultrasound-guided percutaneous biopsy. This technique is helpful when precise needle-tip localization is needed for biopsies of small lesions. 相似文献
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Pulmonary cystic disease: comparison of Pneumocystis carinii pneumatoceles and bullous emphysema due to intravenous drug abuse 总被引:6,自引:0,他引:6
A rare pulmonary manifestation of the acquired immunodeficiency syndrome or intravenous (IV) drug abuse is upper lobe cystic disease--pneumatoceles in Pneumocystis carinii pneumonia (PCP) and bullous emphysema in IV drug abuse. Because these disorders overlap, the radiographic findings in 56 patients were compared. During a 12-month period, 16 patients less than 40 years of age were found to have bullous emphysema; the 10 who were IV drug abusers constituted group 1. In the same time period, 40 patients with PCP were encountered; the eight (20%) who had or developed pneumatoceles constituted group 2. In both groups, the conventional radiographic manifestations of upper lobe cystic disease were similar. Eight patients underwent computed tomography of the chest. In five patients with bullous disease, the distribution of the bullous lesions was peripheral, with sparing of the central portions of the lungs. In contrast, PCP pneumatoceles in three patients were dispersed throughout the lung parenchyma. 相似文献
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