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51.
Foudda R. Homsy Mutlu Özcan Marwan Khoury Zeina A.K. Majzoub 《The Journal of prosthetic dentistry》2018,119(5):783-790
Statement of problem
The subtractive and additive computer-aided design and computer-aided manufacturing (CAD-CAM) of lithium disilicate partial coverage restorations is poorly documented.Purpose
The purpose of this in vitro study was to compare the marginal and internal fit accuracy of lithium disilicate glass-ceramic inlays fabricated with conventional, milled, and 3-dimensional (3D) printed wax patterns.Material and methods
A dentoform mandibular first molar was prepared for a mesio-occlusal ceramic inlay. Five groups of 15 inlays were obtained through conventional impression and manual wax pattern (group CICW); conventional impression, laboratory scanning of the stone die, CAD-CAM milled wax blanks (group CIDW) or 3D printed wax patterns (group CI3DW); and scanning of the master preparation with intraoral scanner and CAD-CAM milled (group DSDW) or 3D printed wax patterns (group DS3DW). The same design was used to produce the wax patterns in the last 4 groups. The replica technique was used to measure marginal and internal adaptation by using stereomicroscopy. Mixed-model ANOVA was used to assess differences according to the groups and discrepancy location (α=.05).Results
Group DSDW showed the smallest marginal discrepancy (24.3 μm) compared with those of groups CICW (45.1 μm), CIDW (33.7 μm), CI3DW (39.8 μm), and DS3DW (39.7 μm) (P<.001). No statistically significant differences were detected among groups CICW, CIDW, CI3DW, and DS3DW relative to the marginal discrepancy. The internal discrepancy was significantly larger than the marginal discrepancy within all groups (P<.001).Conclusions
Lithium disilicate glass-ceramic inlays produced from digital scans and subtractive milling of wax patterns resulted in better marginal and internal fit accuracy than either conventional impression/fabrication or additive 3D manufacturing. Three-dimensional printed wax patterns yielded fit values similar to those of the conventionally waxed inlays. 相似文献52.
Kocken PL Eeuwijk J Van Kesteren NM Dusseldorp E Buijs G Bassa-Dafesh Z Snel J 《The Journal of school health》2012,82(3):115-122
BACKGROUND: Vending machines account for food sales and revenue in schools. We examined 3 strategies for promoting the sale of lower‐calorie food products from vending machines in high schools in the Netherlands. METHODS: A school‐based randomized controlled trial was conducted in 13 experimental schools and 15 control schools. Three strategies were tested within each experimental school: increasing the availability of lower‐calorie products in vending machines, labeling products, and reducing the price of lower‐calorie products. The experimental schools introduced the strategies in 3 consecutive phases, with phase 3 incorporating all 3 strategies. The control schools remained the same. The sales volumes from the vending machines were registered. Products were grouped into (1) extra foods containing empty calories, for example, candies and potato chips, (2) nutrient‐rich basic foods, and (3) beverages. They were also divided into favorable, moderately unfavorable, and unfavorable products. RESULTS: Total sales volumes for experimental and control schools did not differ significantly for the extra and beverage products. Proportionally, the higher availability of lower‐calorie extra products in the experimental schools led to higher sales of moderately unfavorable extra products than in the control schools, and to higher sales of favorable extra products in experimental schools where students have to stay during breaks. Together, availability, labeling, and price reduction raised the proportional sales of favorable beverages. CONCLUSION: Results indicate that when the availability of lower‐calorie foods is increased and is also combined with labeling and reduced prices, students make healthier choices without buying more or fewer products from school vending machines. Changes to school vending machines help to create a healthy school environment. 相似文献
53.
Lupo PJ Langlois PH Reefhuis J Lawson CC Symanski E Desrosiers TA Khodr ZG Agopian AJ Waters MA Duwe KN Finnell RH Mitchell LE Moore CA Romitti PA Shaw GM;National Birth Defects Prevention Study 《Environmental health perspectives》2012,120(6):910-915
Background: Exposure to polycyclic aromatic hydrocarbons (PAHs) occurs in many occupational settings. There is evidence in animal models that maternal exposure to PAHs during pregnancy is associated with gastroschisis in offspring; however, to our knowledge, no human studies examining this association have been conducted.Objective: Our goal was to conduct a case–control study assessing the association between estimated maternal occupational exposure to PAHs and gastroschisis in offspring.Methods: Data from gastroschisis cases and control infants were obtained from the population-based National Birth Defects Prevention Study for the period 1997–2002. Exposure to PAHs was assigned by industrial hygienist consensus, based on self-reported maternal occupational histories from 1 month before conception through the third month of pregnancy. Logistic regression was used to determine the association between estimated occupational PAH exposure and gastroschisis among children whose mothers were employed for at least 1 month during the month before conception through the third month of pregnancy.Results: The prevalence of estimated occupational PAH exposure was 9.0% in case mothers (27 of 299) and 3.6% in control mothers (107 of 2,993). Logistic regression analyses indicated a significant association between occupational PAHs and gastroschisis among mothers ≥ 20 years of age [odds ratio (OR) = 2.53; 95% confidence interval (CI): 1.27, 5.04] after adjusting for maternal body mass index, education, gestational diabetes, and smoking. This association was not seen in mothers < 20 years (OR = 1.14; 95% CI: 0.55, 2.33), which is notable because although young maternal age is the strongest known risk factor for gastroschisis, most cases are born to mothers ≥ 20 years.Conclusion: Our findings indicate an association between occupational exposure to PAHs among mothers who are ≥ 20 years and gastroschisis. These results contribute to a body of evidence that PAHs may be teratogenic. 相似文献
54.
Marie-Hélène Gannagé-Yared Chirine Farès Tony Ibrahim Zeina Abou Rahal Michele Elias Dania Chelala 《Metabolism: clinical and experimental》2013
Objective
Third generation parathyroid hormone (PTH) assays are new generation assays that do not recognize the PTH7–84 fragment whereas second generation assays detect both PTH1–84 and PTH7–84 fragments. Despite the excellent correlation between both assays in chronic renal failure (CRF) subjects, the mean PTH levels are typically 50% lower with the third compared to the second generation assays. The assessment of third generation PTH assays has not been extensively studied in hemodialysis subjects. The purpose of our study was to compare a third generation PTH assay to a second generation one in a population of hemodialysis subjects.Materials and methods
92 haemodialysis subjects (36 women and 56 men) with a mean age of 67±12.9 years were included in this study. Anthropometric and clinical parameters (Body Mass Index (BMI) and blood pressure) were measured. Second and third generation PTH assays (Cis biomedical and Diasorin respectively) were performed in each subject. In addition, the following biochemical tests were measured: 25-hydroxyvitamin D (25-(OH)D), 1,25-hydroxyvitamin D (1,25-(OH)2D), crosslaps and alkaline phosphatase.Results
The mean second and third generation PTHs are respectively 211±205 pg/ml and 151±164 pg/ml. The mean third generation PTH values are 28.4% lower compared to the second generation ones. Both methods are strongly correlated (r = 0.923, p < 0.001). This correlation persisted without any significant difference after controlling for gender, age, BMI and Blood Pressure. However, the difference between both methods increases when baseline PTH increases. Each of the second and third generation method is significantly correlated with hemodialysis duration (p < 0.01), crosslaps (p < 0.001), alkaline phosphatase (p < 0.05), but not with age, BMI, Blood Pressure, 25-(OH)D or 1,25-(OH) 2D levels.Conclusion
Our results show that both second and third generation PTH methods are strongly correlated in hemodialysis patients mainly when PTH values are low. However, the difference between both methods increases when PTH values are high. More research is needed to establish which method is the gold standard when PTH values are high. 相似文献55.
M. A. Rashwan M. Ayman S. Ashour M. M. Hassanin A. A. Zeina 《Heart (British Cardiac Society)》1995,73(3):284-289
The detailed features of right sided endomyocardial fibrosis are described in 15 out of 10,000 consecutive patients who all had infection with Schistosoma mansoni and came from rural Egypt. Laboratory investigations, 12 lead electrocardiography, chest radiography, and Doppler echocardiography were performed in all patients. Cardiac catheterisation and angiography were performed in eight. Endomyocardial biopsy specimens were obtained from the right ventricles of two patients and pericardial biopsy specimens from two. Pericardiocentesis was performed in all patients. All patients were infected with S mansoni and had schistosomal hepatic fibrosis and ascites. Eleven had splenomegaly. All patients had raised cervical venous pressure with prominent Y descent and atrial fibrillation. Eosinophilia was notably absent. Echocardiography showed apical fibrosis in the right ventricle, obliteration of the ventricle, and moderate to massive exudative pericardial effusion in all patients. Calcification and fibrosis extended into the right ventricular outflow tracts in two patients. Huge right atrial thrombi occurred in five patients. Tricuspid regurgitation (grades I-II) was detected in 11 patients by Doppler ultrasonography. Haemodynamic and angiographic data confirmed the pure right sided restrictive pathophysiology. Pericardial biopsy specimens showed perivascular inflammatory infiltrates in two patients and a schistosomal granuloma in one. Endocardial biopsy specimens showed dense fibrosis with many fibroblasts. Endomyocardial fibrosis in Egypt is unique in several aspects. It always affected only the right side of the heart. Calcification and fibrosis extended to the right ventricular outflow tract. Pericardial inflammatory reaction was present. The relation to schistosomiasis and the link to periportal hepatic fibrosis in these patients is intriguing. 相似文献
56.
57.
Martinez Rodriguez NR Eloi MD Huynh A Dominguez T Lam AH Carcamo-Molina D Naser Z Desharnais R Salzman NH Porter E 《Infection and immunity》2012,80(1):266-275
Paneth cells residing at the base of the small intestinal crypts contribute to the mucosal intestinal first line defense by secreting granules filled with antimicrobial polypeptides including lysozyme. These cells derive from the columnar intestinal stem cell located at position 0 and the transit amplifying cell located at position +4 in the crypts. We have previously shown that Salmonella enterica serovar Typhimurium (ST), a leading cause of gastrointestinal infections in humans, effects an overall reduction of lysozyme in the small intestine. To extend this work, we examined small-intestinal tissue sections at various time points after ST infection to quantify and localize expression of lysozyme and assess Paneth cell abundance, apoptosis, and the expression of Paneth cell differentiation markers. In response to infection with ST, the intestinal Paneth cell-specific lysozyme content, the number of lysozyme-positive Paneth cells, and the number of granules per Paneth cell decreased. However, this was accompanied by increases in the total number of Paneth cells and the frequency of mitotic events in crypts, by increased staining for the proliferation marker PCNA, primarily at the crypt side walls where the transit amplifying cell resides and not at the crypt base, and by apoptotic events in villi. Furthermore, we found a time-dependent upregulation of first β-catenin, followed by EphB3, and lastly Sox9 in response to ST, which was not observed after infection with a Salmonella pathogenicity island 1 mutant deficient in type III secretion. Our data strongly suggest that, in response to ST infection, a Paneth cell differentiation program is initiated that leads to an expansion of the Paneth cell population and that the transit amplifying cell is likely the main progenitor responder. Infection-induced expansion of the Paneth cell population may represent an acute intestinal inflammatory response similar to neutrophilia in systemic infection. 相似文献
58.
59.
Objective: Partial demarcation and infarction of the upper pole of the spleen is not a rare occurrence after laparoscopic sleeve gastrectomy (LSG). However, development of an abscess in the absence of leakage is extremely rare. Case Reports: We present herein two unusual case reports of splenic abscess in patients following LSG. Copyright ? 2012 S. Karger GmbH, Freiburg. 相似文献
60.