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Rosangela Saga Kamikawa Marlene Fenyo Pereira Angela Fernandes Maria Inês Meurer 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2006,101(3):374-378
OBJECTIVE: To determine the location in soft tissues of the calcifications, similar to calcified carotid atheromas, that can be observed radiographically in the cervical region in panoramic radiographs. STUDY DESIGN: In each anatomic cadaver specimen preserved in formol, consisting of the head and neck, radiopaque spheres (made from gutta-percha) were positioned in anatomic structures of the cervical region that can be sites of calcification. For each anatomic structure marked in this way, panoramic radiography was performed, consisting of 17 radiographs. The images obtained were analyzed by 24 examiners who indicated which radiographs, in their opinion, presented the radiopaque reference projected in the region of bifurcation of the carotid artery. Analysis of 2 proportions from agreement and disagreement was used to determine radiopacities that could be confused in panoramic radiographs with calcified atheromas in the carotid artery. RESULTS: The results showed that 75% (18) of the examiners correctly indicated the reference in the bifurcation of the carotid artery and 79.2% (19) indicated a triticeous cartilage as calcified atheroma of the carotid artery. CONCLUSIONS: Calcified atheromas of the carotid artery are not the only features that can produce radiopaque images lateral to the panoramic radiograph; the presence of calcification in the triticeous cartilage also can induce an erroneous diagnosis of calcified carotid atheroma. 相似文献
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L C Meurer R L Tolman E W Chapin R Saperstein P P Vicario M M Zrada M MacCoss 《Journal of medicinal chemistry》1992,35(21):3845-3857
A series of alkyl- and halo-substituted 8-(1-piperazinyl)imidazo[1,2-a]pyrazines were prepared using two approaches, the condensation of alpha-halocarbonyl derivatives with an aminopyrazine or the oxidation-dehydration of a [(beta-hydroxyalkyl)amino]pyrazine. These imidazo[1,2-a]pyrazines were evaluated for their binding affinity to the alpha 1, alpha 2, beta 1, and beta 2 adrenergic receptors as well as their ability to lower blood glucose in insulin resistant hyperglycemic ob/ob mice. Modifications on 8-(1-piperazinyl)imidazo[1,2-a]pyrazine (4) reduced alpha 2 binding, lowered hypoglycemic potency, and showed variations in binding to the alpha 1, beta 1, and beta 2 adrenergic receptors. In addition to 4, the 2-methyl, 3-methyl, and 5-methyl 8-(1-piperazinyl)imidazo[1,2-a]pyrazines (16k, 25m, and 16f, respectively) displayed high affinity for the alpha 2 receptor and were potent hypoglycemic agents when compared to 2-amino-7,8-dihydro-4-(1-piperazinyl)-6H-thiopyrano[3,2- d]pyrimidine (MTP-1403, 2). Receptor binding was modified by use of a 4-methylpiperazine moiety which reduced alpha 1 and beta 1 binding while retaining some hypoglycemic activity. The structure-activity relationship for heterocyclic alkyl and halo substitution on biological activity is discussed. 相似文献
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AR Jones BSC AJP Sandison FRCS WJ Owen MS FRCS 《International journal of clinical practice》1997,51(5):294-295
Pre-clerking of all patients undergoing elective general surgical operations was introduced at our hospital in an attempt to reduce an unacceptably high operation cancellation rate. A prospective audit has been performed on the effect of this policy on the cancellation rate. Before the introduction of pre-clerking there was a marked seasonal variation in the number of patients who failed to attend for surgery, which could be explained by absence on holiday. This seasonal variation disappeared after the start of pre-clerking clinics, but there has been no reduction in the number of cancellations for medical reasons. 相似文献
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Berbaum KS; el-Khoury GY; Franken EA Jr; Kathol M; Montgomery WJ; Hesson W 《Radiology》1988,168(2):507-511
The effect of knowledge of localizing symptoms and signs in the detection of fractures was studied. Forty radiographs of the extremities were examined twice by seven radiologists; the sessions were separated by 4 months. In 26 cases, a subtle fracture was present; 14 cases were normal. In half of the cases at each session, the precise location of pain, tenderness, or swelling was provided. The observer was asked to determine if the case was normal or abnormal (provide the exact location of the fracture) and to indicate the degree of confidence in the diagnosis. Responses were converted to a numeric scale for analysis. Analysis of receiver operator characteristic parameters indicates that clues regarding location of trauma facilitate detection of fractures. The improvement is based largely on an increased true-positive rate without an increased false-positive rate, regardless of the decision criteria of the radiologist (overall willingness to "overread" or "underread"). This has direct clinical applicability and reinforces the plea of radiologists for precise clinical information. 相似文献
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Lei Wan, Poliporus mylittae Cook et Mass(Omphalia lapidescena Scbraet) is a kind of fungus used in traditional Chinese medicine, as an antheiminthie From Lei Wan, an "active component designated as. S-4001 had been isolated.Preliminary results indicate that S-4001 belongs to D, β, 1-3 glucan with some 1-6 linkages.After administration of S-4001, significant antiinflammatory activity was found in various experimental animal models, including croton oil induced ear edema in mice and agar or yeast induced ankle swelling in rats. An inhibitory action on leucocyte migration inducced by intraperitoneal injection of CMC in rats was also observed. The plasma content of corticosterone was significantly increased, but the content of ascorbic acid in the adrenals did not change in rats given S-4001. Apart from these actions, S-4001 showed a number of immunostimulating actions such as increasing the clearance of Congo red from mice blood and potentiating the immunohemolysis reaction in 615 mice. 相似文献
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