54 research outputs found
The accuracy of citations in medicine and master degree dissertations, Shahrekord University of Medical Sciences, 2006- 2012
زمینه و هدف: پایان نامه ها به عنوان یک منبع علمی بوده و نحوه استناد دقیق به پایان نامه ها با اهمیت است. مطالعه حاضر با هدف تعیین نحوه استناد های مورد استفاده در پایان نامه های دانشجویان پزشکی و کارشناسی ارشد دانشگاه علوم پزشکی شهرکرد در سال های 1391- 1385 انجام شده است. روش بررسی: در این مطالعه مقطعی، 275 پایان نامه کارشناسی ارشد و پزشکی دفاع شده در دانشگاه علوم پزشکی شهرکرد از سال 1385 تا پایان سال 1391، با روش سرشماری مورد ارزیابی قرار گرفت. اطلاعات مرتبط با منابع مورد استفاده در پایان نامه ها شامل اشکالات مرتبط با استناد از نظر نوع و فراوانی منابع مورد استفاده، روش استناد، دقت و نوع اشکال در هر منبع، با استفاده از چک لیست مورد بررسی قرار گرفت. یافته ها: از 275 پایان نامه مورد بررسی، 27 مورد پایان نامه کارشناسی ارشد و 248 مورد پایان نامه پزشکی بود. هشت پایان نامه کارشناسی ارشد (62/29) و 74 پایان نامه(83/29) پزشکی فاقد اشکال بودند. میانگین تعداد خطا در پایان نامه های کارشناسی ارشد 88/6±56/7 و در پایان نامه های پزشکی 23/14±92/8 بود. از نظر فراوانی بیشترین خطا مربوط به اشتباه در منبع نویسی کتب لاتین و مقالات لاتین بود. نتیجه گیری: به نظر می رسد نحوه استناد در پایان نامه های کارشناسی ارشد و پزشکی مطلوب نمی باشد و برنامه ریزی و برگزاری کلاس های آموزشی در این زمینه برای دانشجویان و اساتید مربوطه ضروری است
Cyclosporin A differentially inhibits multiple steps in VEGF induced angiogenesis in human microvascular endothelial cells through altered intracellular signaling
The immunosuppressive agent cyclosporin A (CsA), a calcineurin inhibitor which blocks T cell activation has provided the pharmacologic foundation for organ transplantation. CsA exerts additional effects on non-immune cell populations and may adversely effect microvascular endothelial cells, contributing to chronic rejection, a long-term clinical complication and significant cause of mortality in solid-organ transplants, including patients with small bowel allografts. Growth of new blood vessels, or angiogenesis, is a critical homeostatic mechanism in organs and tissues, and regulates vascular populations in response to physiologic requirements. We hypothesized that CsA would inhibit the angiogenic capacity of human gut microvessels. Primary cultures of human intestinal microvascular endothelial cells (HIMEC) were used to evaluate CsA's effect on four in vitro measures of angiogenesis, including endothelial stress fiber assembly, migration, proliferation and tube formation, in response to the endothelial growth factor VEGF. We characterized the effect of CsA on intracellular signaling mechanisms following VEGF stimulation. CsA affected all VEGF induced angiogenic events assessed in HIMEC. CsA differentially inhibited signaling pathways which mediated distinct steps of the angiogenic process. CsA blocked VEGF induced nuclear translocation of the transcription factor NFAT, activation of p44/42 MAPK, and partially inhibited JNK and p38 MAPK. CsA differentially affected signaling cascades in a dose dependent fashion and completely blocked expression of COX-2, which was integrally linked to HIMEC angiogenesis. These data suggest that CsA inhibits the ability of microvascular endothelial cells to undergo angiogenesis, impairing vascular homeostatic mechanisms and contributing to the vasculopathy associated with chronic rejection
Dickkopf-1 (DKK1) promotes tumor growth via Akt-phosphorylation and independently of Wnt-axis in Barrett’s associated esophageal adenocarcinoma
Esophageal adenocarcinoma (EAC) is still associated with poor prognosis, despite modern multi-modal therapies. New molecular markers, which control cell cycle and promote lymph node metastases or tumor growth, may introduce novel target therapies. Dickkopf-1 (DKK1) is a secreted glycoprotein that blocks the oncogenic Wnt/β-catenin signaling and its aberrant expression has been observed in many malignancies, including EAC. In this study, we investigated the biological role of DKK1 in EAC. Analysis of DKK1 and active β-catenin expression in human esophageal tissues confirmed a simultaneous DKK1-overexpression together with aberrant activation of β-catenin signaling in EAC in comparison with Barrett’s and healthy mucosa. To elucidate the molecular role of DKK1, the OE33 adenocarcinoma cells, which were found to overexpress DKK1, were subjected to functional and molecular assays following siRNA-mediated DKK1-knockdown. At the functional level, OE33 cell viability, proliferation, migration and invasion were significantly attenuated by the absence of DKK1. At the molecular level, neither DKK1-knockdown nor application of exogenous recombinant DKK1 were found to alter the baseline β-catenin signaling in OE33 cells. However, DKK1-knockdown significantly abrogated downstream Akt-phosphorylation. On the other hand, the Wnt-agonist, Wnt3a, restored the Akt-phorphorylation in the absence of DKK1, without, however, being able to further stimulate β-catenin transcription. These findings suggest that the β-catenin transcriptional activity in EAC is independent of Wnt3a/DKK1 site-of-action and define an oncogenic function for DKK1 in this type of malignancy via distinct activation of Akt-mediated intracellular pathways and independently of Wnt-axis inhibition. Taken together, DKK1 may present a novel therapeutic target in EAC
Oxidative desulfurization of diesel by potato based-carbon as green support for H5PMo10V2O40: Efficient composite nanorod catalyst
The C@POM (carbon@polyoxometalate) containing H3PMo12O40 (PMo12), H5PMo10V2O40 (PMo10V2), H6PMo9V3O40 (PMo9V3), H7PMo8V4O40 (PMo8V4), H3PW12O40 (PW), and H4SiW12O40 (SiW) were prepared from natural potato as green, and cheap catalyst support source. The C@PMo10V2 was found to be a unique, effective, and eco-friendly catalyst for selective oxidation of sulfides, using 30% aq. H2O2. C@PMo10V2 composite was characterized by X-ray diffraction spectroscopy (XRD), energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), thermal gravimetric analysis (TGA), Fourier transform infrared (FT-IR) spectrophotometry, zeta sizer, and zeta potential. The XRD results show that during immobilization PMo10V2 on the carbon catalyst support (CCS), the crystallite structure of PMo10V2 and CCS was not changed. The SEM results show that PMo10V2 crystals deposited on the surface CCS rods as composite nanorod structure. A variety of sulfides, sulfur-containing model and real oil were oxidized with the C@PMo10V2/H2O2 at room temperature. Recovered catalyst show excellent activity for at least four repeating cycles
Non-Coding RNA-Based Biosensors for Early Detection of Liver Cancer
Primary liver cancer is an aggressive, lethal malignancy that ranks as the fourth leading cause of cancer-related death worldwide. Its 5-year mortality rate is estimated to be more than 95%. This significant low survival rate is due to poor diagnosis, which can be referred to as the lack of sufficient and early-stage detection methods. Many liver cancer-associated non-coding RNAs (ncRNAs) have been extensively examined to serve as promising biomarkers for precise diagnostics, prognostics, and the evaluation of the therapeutic progress. For the simple, rapid, and selective ncRNA detection, various nanomaterial-enhanced biosensors have been developed based on electrochemical, optical, and electromechanical detection methods. This review presents ncRNAs as the potential biomarkers for the early-stage diagnosis of liver cancer. Moreover, a comprehensive overview of recent developments in nanobiosensors for liver cancer-related ncRNA detection is provided
Non-Coding RNA-Based Biosensors for Early Detection of Liver Cancer
Primary liver cancer is an aggressive, lethal malignancy that ranks as the fourth leading cause of cancer-related death worldwide. Its 5-year mortality rate is estimated to be more than 95%. This significant low survival rate is due to poor diagnosis, which can be referred to as the lack of sufficient and early-stage detection methods. Many liver cancer-associated non-coding RNAs (ncRNAs) have been extensively examined to serve as promising biomarkers for precise diagnostics, prognostics, and the evaluation of the therapeutic progress. For the simple, rapid, and selective ncRNA detection, various nanomaterial-enhanced biosensors have been developed based on electrochemical, optical, and electromechanical detection methods. This review presents ncRNAs as the potential biomarkers for the early-stage diagnosis of liver cancer. Moreover, a comprehensive overview of recent developments in nanobiosensors for liver cancer-related ncRNA detection is provided
A Biocompatible Nanocomposite for Glucose Sensing
A nanocomposite containing amine functionalized multiwalled carbon nanotubes and a room temperature ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate) was prepared and applied for glucose oxidase (GOx) immobilization on glassy carbon electrode. The proposed nanocomposite provided a favorable microenvironment to preserve the bioactivity of GOx. It could also effectively facilitate the enzyme direct electron transfer to the electrode. This brought about a remarkable improvement in the sensitivity of the glucose biosensor. Under the optimum experimental conditions, the formal potential of GOx was about −467.5 mV. Moreover, the sensitivity and response time of the biosensor toward glucose were 1277 μA mM-1 cm-2 and 6 s, respectively. The biosensor provided a linear dynamic response between 0.1 and 43 μM with a very low detection limit of 63 nM. Also, the values for apparent Michaelis-Menten constant and maximum current were obtained as 18 μM and 2.7 μA, respectively
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