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21.
Clinical Oral Investigations - The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) pandemic has created hitherto unknown challenges for healthcare systems and patient care. This study...  相似文献   
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Cancer is the major cause of death and many factors that lead to its occurrences, such as environmental pollution and pesticides and other factors. Ehrlich carcinoma development depends on many things associated with the environment, nutrition, personal habits, and family history. The present study aimed to evaluate the potential protective effects of vitamin B17 (VB17) against Ehrlich ascites carcinoma (EAC) that induced kidney toxicity in female mice. The mice were divided into five groups (first group, control group; second group, VB17 group; third group, EAC group; fourth group, pretreated EAC with VB17; fifth group, cotreated EAC with VB17). Results showed the VB17 in pretreated (G4) and cotreated (G5) groups lead to an improvement in DNA damage and cytological examination, in addition significantly (P < .05) increase in Na+, red blood cell, hemoglobin, hematocrit value, mean corpuscular hemoglobin (MCH), and MCH concentration, whereas significantly (P < .05) decrease in urea, creatinine, K+, platelets, and white blood cells while insignificant (P < .05) changes in mean corpuscular volume when compared to the EAC group. Many histopathological changes were observed in kidney sections in EAC as marked damage and degenerated, glomerular atrophy, the Malpighian corpuscles that lost their characteristic configuration. On the other hand, a moderate improvement and arrangement in the kidney histological structure in pretreated VB17 + EAC, while a mild enhancement and arrangement of the kidney structure in cotreated EAC + VB17. In addition, depletion in renal P53 and PCNA protein expression compared with the EAC group. It could be concluded that VB17 has a potential renal protective effect against EAC cells induced kidney injury.  相似文献   
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Three factors, three levels (33) full factorial design was used to develop venlafaxine HCl fast dissolving oral films (FDOFs) to optimize the concentrations of the film forming polymer; hydroxypropyl methylcellulose HPMC (X1), superdisintegrant; sodium starch glycolate SSG, (X2) and glycerol as the film plasticizer (X3). Effects of the three factors on the disintegration time (Y1), swelling index (Y2), and dissolution efficiency at 15 min; DE%15 (Y3) of the prepared FDOFs were evaluated by using statistical models. The optimized film formula was characterized in term of x-ray powder diffraction (XRPD), differential scanning calorimetry (DSC) and morphological characteristics.Disintegration time was found to increase with the increase in HPMC (X1) concentration, and the shortest disintegration time (21.67 ± 2.08 s) was observed in case of F2 formula (lowest HPMC level and highest glycerol level in absence of SSG). The highest swelling index (3.64 ± 0.59) was observed in case of film formula F1 (medium concentrations of both HPMC and glycerol and highest SSG concentration. The results also indicated that as the concentration of HPMC increased the DE%15 decreased. SSG (X2), with highest value (72.33 ± 1.71%) was recorded for in case of F12 (using 2% HPMC, 5%SSG and 1.5% glycerol). The optimized FDOF formula derived by the statistical models suggested 2% HPMC, 5% SSG, and 1% glycerol.The data obtained from DSC and XRPD revealed no interaction between drug and FDOT excipients. In addition, XRPD studies proved that the venlafaxine HCl was homogeneously dispersed in the film matrix.  相似文献   
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Objective

The purpose of this study was to assess the use of and satisfaction with the academic-advising and student-support systems available to undergraduate students in the College of Dentistry at the University of Dammam. In addition, the study aimed to also identify factors that explained the help-seeking behavior of students which they used to solve academic issues.

Materials and methods

Students enrolled in the five-year Bachelor of Dental Surgery (BDS) program in 2012–13 and 2013–14 first-year students were invited to respond to a self-administered questionnaire.

Results

The results showed that 66.2% of students had discussed academic issues with their advisor at least once, with a frequency ranging from zero to six times. Most students reported that their advisors were readily available, listened intently to their needs and questions, and helped them solve their problems. However, only 7.6% of students relied primarily on advisors for help with academic issues, whereas 51% depended first on colleagues and 13.8% did not seek help and relied on themselves. In total, 17.2% of students were very or somewhat satisfied with the academic advising system. Males had lower odds of discussing issues with their advisors, and the odds were higher with advisors who were more available (OR = 0.25 and 3.74, respectively). Alerting students to important dates in the academic calendar significantly increased the odds that a student would depend primarily on academic advisors for advice related to academic issues (OR = 6.53).

Conclusions

Few students were satisfied with the academic support system. We need to train advisors to help them develop their skills and knowledge and to enable them to provide the support needed by the students.  相似文献   
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Congenital hyperinsulinism (CHI) is caused by unregulated insulin release and leads to hyperinsulinaemic-hypoglycaemia (HH). Glucagon like peptide-1 (GLP-1), glucose-dependent insulinotropic peptide (GIP), peptide YY (PYY) and the enzyme; dipeptidyl peptidase-4 (DPP-4) all regulate appetite and glucose homeostasis. These proteins have been identified as possible contributors to HH but the mechanism remains poorly understood. We aimed to look at the expression pattern of pancreatic DPP-4 in children with focal and diffuse CHI (FCHI and DCHI, respectively). Using immunohistochemistry; we determined DPP-4 expression patterns in the pancreas of CHI patients. DPP-4 was found to be expressed in the pancreatic β, α and δ-cells in and around the focal area. However, it was predominantly co-localised with β-cells in the paediatric tissue samples. Additionally, proliferating β-cells expressed DPP-4 in DCHI, which was absent in the FCHI pancreas. Insulin was found to be present in the exocrine acini and duct cells of the DCHI pancreas suggestive of exocrine to endocrine transdifferentiation. Furthermore, 6 medically-unresponsive DCHI pancreatic samples showed an up-regulation of total pancreatic DPP-4 expression. In conclusion; the expression studies have shown DPP-4 to be altered in HH, however, further work is required to understand the underlying role for this enzyme.  相似文献   
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Periodontitis may affect atherosclerosis via the chronic inflammation. We investigated high-sensitivity C-reactive protein (hsCRP) in relation to early vascular atherosclerotic changes in non-symptomatic subjects with and without long-term periodontitis. Carotid ultrasonography with calculation of common carotid artery intima-media area (cIMA) was performed, and hsCRP and atherosclerosis risk factors were analysed in randomly chosen 93 patients with periodontitis and 41 controls. The relationship between hsCRP, cIMA and atherosclerosis risk factors was evaluated with multiple logistic regression analysis. Women displayed lower hsCRP (p < 0.05) and higher serum HDL (p < 0.001) than men. In all patients with periodontitis, cIMA values were higher than in controls. Periodontitis appeared to be a major predictor for increased cIMA (odds ratio, 3.82; 95% confidence interval, 1.19–12.26). Neither of these factors was significantly associated with hsCRP which thus appeared not sensitive enough to be a marker for periodontitis or atherosclerosis. Hence, irrespective of low hsCRP levels, periodontitis appeared to increase the risk for atherosclerosis.  相似文献   
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