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OBJECTIVE: This study aims to give an insight into the chemical and structural modifications occurring in laser treated dentine surface, as a tool to plan a new class of dental materials specific for the dental restoration when laser technologies are used. For this purpose the effect of Er:YAG (Erbium-Yttrium Aluminium Garnet) laser treatments on human dentine surface has been investigated. METHODS: The dentine surface of periodontally compromised teeth cut along the main axis was treated in vitro with laser pulses having the same energy but time duration varying in the range of 100-1000 micros. The chemical characteristics and the morphology of the laser treated surface have been studied with micro-Raman spectroscopy (micro-RS) and scansion electron microscopy (SEM). RESULTS: The micro-RS and SEM analysis of laser treated teeth have been compared with those of surfaces treated with conventional mechanical methodologies. The laser pulse time duration affects the surface morphology and the chemistry of dentine, mainly of organic components. The effects have been monitored by analysing the C-H group stretch vibration mode of the micro-RS spectrum. CONCLUSION: The laser treatment can determine different chemical microenvironments on the treated dentine surface, depending on the time duration of laser pulse used. Treatments with very long pulse results in a the dentine surface very similar to that obtained with a conventional mechanical drill, while with very short laser pulses a strong modification of the dentine organic components has been observed.  相似文献   
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The purpose of this study was to evaluate the axillary node displacement away from chest wall and their anatomical location in relation to the humeral head, according to the position of the arms, when the axilla is the site of enlarged nodes. In 13 patients with enlarged axillary nodes, the anatomical span of the nodes according to two arms positions, akimbo (A) and up over the head (U), was prospectively evaluated using computed tomography (CT) and magnetic resonance imaging (MRI). The nodes were classified into two groups, i.e. the lower and upper groups. The mean distances of the lower node group from the chest wall when the patients were in A, and U positions were 3 cm and 6.4 cm, respectively (p=0.002). The upper group nodes showed a smaller difference in the distance from the chest wall: in A position, mean 2.1 cm; in U position 2.8 cm (p=0.03). In U position, there was always a node of the lower group that was displaced in front of the humeral head. This study demonstrates the displacement of enlarged axillary nodes according to the position of the arms. In patients with axillary node involvement, CT planning should be considered when they have their arms held up over their heads.  相似文献   
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OBJECTIVE: This study evaluated the correlation between vital signs and hemoperitoneum and the association between abnormal vital signs and tubal rupture. STUDY DESIGN: With the use of a retrospective case-control design, the initial heart rate, systolic blood pressure, and heart rate/systolic blood pressure were correlated with respect to degree of hemoperitoneum; predictive values were calculated. RESULTS: Fifty-two patients were studied (25 ruptured pregnancies and 27 unruptured ectopic pregnancies). Correlation coefficients were heart rate (r=0.50; 95% CI, 0.26-0.68), systolic blood pressure (r=-0.34; 95% CI, -0.56 to -0.08), and heart rate/systolic blood pressure (r=0.69; 95% CI, 0.51-0.81). The sensitivity for heart rate, systolic blood pressure, and heart rate/systolic blood pressure was 28%, 36%, and 72% respectively; the specificity was 96%, 96%, and 67%, respectively. CONCLUSION: Normal vital signs alone are poor predictors of ruptured ectopic pregnancy; the heart rate/systolic blood pressure correlates best with the quantity of intraperitoneal hemorrhage.  相似文献   
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Purpose: To evaluate the accuracy of MR pyelography in the assessment of hydroureteronephrosis.Material and Methods: One hundred and fifteen patients, with variable degree of hydroureteronephrosis demonstrated by US and urography were subjected to MR pyelography obtained by means of two ultra-fast sequences.Results: Of the 228 kidneys examined, the collecting systems of 130 kidneys were dilated and correctly identified on MR pyelography, with only 2 false-positive results. The specificity of MR pyelography in detecting hydronephrosis was 98%. Accuracy in revealing level of obstruction was 100%. Sensitivity in detecting stones, strictures and congenital ureteropelvic junction obstructions was respectively 68.9%, 98.5% and 100%.Conclusion: MR pyelography can rapidly and accurately depict the morphological features of dilated urinary tracts with information regarding the degree and level of obstruction, without using contrast medium or ionizing radiation.  相似文献   
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Visceral involvement in eosinophilic fasciitis (EF) is a well known but rare event. With regard to neurological manifestations, both carpal tunnel syndrome and peripheral neuropathy have been described. We report the case of a 40-year-old woman with EF who had a major motor seizure. This association might not be fortuitous and be related to the known neurotoxin of eosinophils. Received: 22 February 1999 / Accepted: 4 December 2000  相似文献   
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In a case-control study to understand the risk factors for development of life-threatening dehydration, a total of 379 children comprising 243 cases (moderate or severe dehydration) and 136 controls (non or mild dehydration) up to 2 years of age suffering from acute watery diarrhoea were studied. By univariate analysis, the presence of vibrios in stool, withdrawal of breast feeding during diarrhoea, not giving fluids, including oral rehydration solution (ORS), during diarrhoea, frequent purging (> 8/ day), vomiting (> 2/day) and undernutrition were identified as risk factors. However, by multivariate analysis after controlling for confounders, withdrawal of breast feeding during diarrhoea (odds ratio (OR) = 6.8, p < 0.00001) and not giving ORS during diarrhoea (OR = 2.1, p < 0.006) were identified as significant risk factors. The confounding variables which also contributed significantly to increasing the risk were age (≤ 12 months; OR = 2.7, p = 0.001), frequent purging (> 8/day; OR = 4.1, p < 0.00001), vomiting (> 2/day; OR = 2.4, p = 0.001) and severe undernutrition (%median <60 weight-for-age of Indian Academy of Paediatrics classification; OR = 3.1, p = 0.001). We feel that these findings will be useful for Global and National Diarrhoeal Diseases Control Programmes for formulating intervention strategies for preventing death due to diarrhoeal dehydration.  相似文献   
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A 13-year-old male with a history of chronic congenital megacolon presented to the emergency department with a 1-day history of increasing abdominal pain, distension, and emesis. The patient was admitted for bowel disimpaction and irrigation. The patient rapidly developed an acute abdominal compartment syndrome because of his massive colonic dilation. Surgical decompression resulted in a reperfusion phenomenon and ultimately resulted in coagulopathy and patient demise. This case presents a unique cause of the abdominal compartment syndrome and discusses the implications to the emergency physician.  相似文献   
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