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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   
13.
This research presents reports of cases where a biocompatible and alloplastic biomaterial—Bioplastique—was used, associated with conventional plastic surgery or as a complement to it, with the aim of achieving a better final aesthetic result. Four cases are presented where Bioplastique was used in association with rhytidoplasty, rhinoplasty, and other surgical techniques. This material has shown itself to be appropriate to complement surgery; achieving a final result which would not be possible without any resort to a complement or any other hard procedure by the surgeon and is not more traumatic for the patient.  相似文献   
14.
Transitional progressive multiple sclerosis: MRI and MTI findings   总被引:1,自引:0,他引:1  
Transitional progressive multiple sclerosis (MS) is quite an unusual form of presentation and course of the disease. A case with this progressive form is presented and brain MRI and MTI findings are discussed in relation to the possible insight they may provide for understanding the mechanisms that determine progressive disability in MS.  相似文献   
15.
Rat neutrophil chemotactic responses to N-formyl-methionyl-leucyl-phenylalanine (FMLP), leukotriene (LT) B4, and lipopolysaccharide-activated serum (LPS-AS) were quantitatively assessed using the micropore filter system. Cells were suspended in either normal or diabetic rat serum for testing. Diabetic donor serum did not affect migration of neutrophils in a concentration gradient of the synthetic chemotactic agents. In contrast, the migratory responses to LPS-AS were significantly less than normal in this circumstance. Summation of effects was observed when FMLP and LPS-AS, or LTB4 and LPS-AS were simultaneously added to the test chamber, with cells suspended in normal serum. Suspended in diabetic rat serum neutrophils responded normally to the synthetic chemoattractants but the response to the activated serum was blocked. Cells previously incubated in the presence of diabetic donor serum then transferred to a culture medium for testing, presented reduced migratory responses to LPS-AS. Supramaximal, inhibitory concentrations of FMLP and LTB4, did not influence the response of neutrophils to LPS-AS. In vivo, suppression of cellular emigration to an inflamed area was observed from the early stages of the diabetic state. The inhibitory activity of chemotaxis in diabetes mellitus was previously reported to be associated with a protein factor in plasma of the animals. It is suggested that the inhibitory factor of chemotaxis in diabetes mellitus interacts with neutrophil receptors for complement-derived chemoattractants to induce blockade of cell-oriented locomotion either in vitro or in vivo.  相似文献   
16.
The efficacy and safety of using umbilical venous catheters vs. peripheral venous catheters for the delivery of parenteral nutrition was studied in 129 critically ill premature infants who were treated in a neonatal intensive care unit for the first 3 weeks of life. Infants who received parenteral nutrition by umbilical venous catheter had greater parenteral caloric intake, lower physiologic weight loss and greater weight gain during the study as compared to infants who received parenteral nutrition by peripheral vein. While the overall incidence of sepsis was comparable in both groups (19% vs 19.7%), benign and transient episodes of hyperglycemia were seen more commonly in infants receiving parenteral nutrition by umbilical catheters. None of the hyperglycemic infants, however, required insulin therapy. The incidence of other metabolic complication was comparable in both groups. At follow up, no evidence of portal hypertension was detected in any of the infants up to 66 months of age treated with umbilical venous catheters. We conclude that the use of umbilical venous catheter allows for a comparably safe and a more appropriate parenteral nutrition support than peripheral catheters in critically ill premature neonates.  相似文献   
17.
Orthotopic liver transplantation was performed in 20 pigs. Serum total bile acids (STBA) were determined and their profile compared with standard early function parameters: total bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactic acid. In phase I, the STBA level was 32.89 +/- 1.29 mumol/l. In phase II, STBA accumulated to 84.46 +/- 15.25 mumol/l (p less than 0.01), followed by hepatic clearance in phase III (63.61 +/- 9.71 mumol/1; NS). Between phase III and 6- and 12-hour samples, STBA decreased progressively, reaching values of 33.63 +/- 7.05 mumol/l at 24 h. AST was elevated in phases I, II, III, and at 6, 12 and 24 h (p less than 0.001), as was ALT (but with insignificant differences). Thus, STBA and their profile appear to be earlier and more specific indicators of early graft function than conventional parameters.  相似文献   
18.
BACKGROUND: In 1998, the UK government issued precautionary advice that pregnant or breast-feeding women with a family history of atopy, may wish to avoid eating peanuts during pregnancy and lactation. This study aimed to assess the compliance with this recommendation and investigate its impact upon peanut sensitization. METHODS: A total of 858 children born immediately after the advice were followed for 2 years and assessed for peanut sensitization. A standardized questionnaire was used to ascertain history of atopy and maternal exposure to peanuts during pregnancy. Following parental consent children were skin prick tested to assess sensitization to peanuts. RESULTS: Sixty-five per cent of mothers had avoided peanuts during pregnancy. Forty-two per cent of the mothers had heard about the government advice, and half modified their diet as a consequence. Neither maternal nor family history of atopy had any significant effect on peanut consumption. Parity did play a role, and mothers having their first child were twice as likely to change their diet (P<0.001). Mothers of 77% of the children sensitized to peanuts had avoided peanuts during pregnancy. In this cohort study maternal consumption of peanut during pregnancy was not associated with peanut sensitization in the infant. CONCLUSIONS: The majority of mothers in this cohort avoided peanut consumption during pregnancy. It is likely that either the government advice is misunderstood by mothers, or that those who communicate the advice have not fully explained who it is targeted at.  相似文献   
19.
The anatomic response to intravitreal bevacizumab injection in three patients with aggressive, posterior retinopathy of prematurity is described. In all cases, the worse eye was treated with a single intravitreal injection of 0.75 mg of bevacizumab as monotherapy or complementary to laser therapy. In 24 hours, all injected eyes showed regression of the tunica vasculosa lentis and iris vessel engorgement and disappearance of iris rigidity. In addition, plus disease and retinal proliferation began to regress. None of the eyes required additional treatment. Follow-up of up to 10 months  相似文献   
20.
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