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排序方式: 共有875条查询结果,搜索用时 46 毫秒
1.
Fardin Moradi Vahid Maleki Sevda Saleh‐Ghadimi Fatemeh Kooshki Bahram Pourghassem Gargari 《Clinical and experimental pharmacology & physiology》2019,46(11):975-983
Diabetes, as a low‐grade chronic inflammatory disease, causes disruption in proper function of immune and metabolic system. Chromium is an important element required for normal lipid and glucose metabolism. Chromium deficiency is correlated with elevation in cardiometabolic risk, which results from increased inflammation. This systematic review was conducted to discover the potential roles of chromium on inflammatory biomarkers. Eligible studies were all in vitro, animal and human studies published in English‐language journals from inception until October 2018. PubMed, Scopus, Embase, ProQuest and Google Scholar databases were searched to fined interventional studies from the effects of chromium on inflammatory biomarkers such as tumour necrosis factor a (TNF‐a), C‐reactive protein (CRP), interleukins, monocyte chemoattractant protein–1 (MCP‐1), intercellular adhesion molecule‐1 (ICAM‐1) and adipocytokines in hyperglycaemia and diabetes. Out of 647 articles found in the search, only 14 articles were eligible for analysis, three in vitro studies, eight animal studies and three human studies. Twelve of the 14 studies included in this review, chromium significantly decreased inflammatory factors. The findings of this review indicate, based on in vitro and in vivo studies, that chromium might have potential anti‐inflammatory properties, but some of the studies did not show anti‐inflammatory effects for chromium (two studies). There are only three studies in humans with controversial results. Therefore, more consistent randomized double‐blind controlled trials are needed to reach relevant clinical recommendations, as well as to determine the precise mechanism, of chromium on inflammation in diabetes. 相似文献
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3.
Bahram Dalir-Naghadeh Siamak Asri-Rezaei Naser Alidady 《Comparative clinical pathology》2006,15(3):149-153
Odds ratio was used to evaluate relationship between sepsis in cattle less than 1 year old and mastitis in cows and erythrocyte glutathione peroxides (GSH-PX) activity as an indicator of selenium status. Data were from 178 blood samples collected from referred cases to Urmia University, Veterinary Teaching Hospital. Low activity of GSH-PX was significantly associated with higher odds of developing sepsis (P=0.005) in young cattle and mastitis (P=0.044) in adult cows. The odds ratios for the low activity of GSH-PX on incidence of sepsis and mastitis were 4.74 and 3.95, respectively. Selenium deficiency was associated with sepsis in young cattle and mastitis in cows, i.e., cattle with low activity of erythrocyte GSH-PX were at increased risk of sepsis and mastitis. 相似文献
4.
Mechanisms of cold sensitivity of paramyotonia congenita mutation R1448H and overlap syndrome mutation M1360V 总被引:1,自引:2,他引:1
Bahram Mohammadi Nenad Mitrovic Frank Lehmann-Horn Reinhard Dengler Johannes Bufler 《The Journal of physiology》2003,547(3):691-698
Missense mutations of the human skeletal muscle voltage-gated Na+ channel (hSkM1) cause a variety of neuromuscular disorders. The mutation R1448H results in paramyotonia congenita and causes cold-induced myotonia with subsequent paralysis. The mutation M1360V causes an overlapping syndrome with both K+ -induced muscle weakness and cold-induced myotonia. The molecular mechanisms of the temperature dependence of these disorders are not well understood. Therefore we investigated physiological parameters of these Na+ channel mutations at different temperatures. Channel proteins were recombinantly expressed in human embryonic kidney cells and studied electrophysiologically, using the whole-cell patch-clamp technique. We compared the wild-type (WT) channel with both mutants at different temperatures. Both mutations had slower inactivation and faster recovery from inactivation compared to WT channels. This effect was more pronounced at the R1448H mutation, leading to a larger depolarization of the cell membrane causing myotonia and paralysis. The voltage dependence of activation of R1448H was shifted to more negative membrane potentials at lower temperature but not at the M1360V mutation or in the WT. The window current by mutation R1448H was increased at lower temperatures. The results of this study may explain the stronger cold-induced clinical symptoms resulting from the R1448H mutation in contrast to the M1360V mutation. 相似文献
5.
Genetics of the central MHC 总被引:4,自引:0,他引:4
The MHC, primarily known for its antigen-presenting class I and II molecules, harbours, within a central segment of less than 1 Mb, a dense collection of genes involved in various biological functions. Although MHC I and MHC II are principal players of adaptive immunity, several loci within this central (still called class III) MHC region encode members of the innate immune system. These include the long known factors of the complement system--potentially inhibitory and triggering natural killer receptors as well as stress proteins. Whether this physical proximity is fortuitous or functionally advantageous is an important question for the future of MHC genetics. 相似文献
6.
Lisa M. Rooper Lester D. R. Thompson Jeffrey Gagan Bahram R. Oliai Ilan Weinreb Justin A. Bishop 《Head and neck pathology》2021,15(1):179
Intraductal carcinoma (IDC) is a rare salivary gland tumor that is considered analogous to ductal carcinoma in-situ of the breast, demonstrating a complex neoplastic epithelial proliferation surrounded by a continuous layer of presumed non-neoplastic myoepithelial cells. It is subcategorized into intercalated duct, apocrine, and hybrid subtypes based on morphologic and immunohistochemical features, with frequent NCOA4-RET and TRIM27-RET fusions, respectively, seen in intercalated duct and hybrid tumors. However, as an expanding clinicopathologic spectrum of IDC has been documented, controversy has emerged as to whether this tumor type is best defined by its intraductal growth pattern or distinctive molecular and immunophenotypic differentiation. Here, we further explore the nature of IDC by evaluating four cases that arose within intraparotid lymph nodes. These intercalated-duct phenotype tumors with diffuse S100 protein expression demonstrated a crowded and complex epithelial proliferation arranged in cystic, cribriform, and micropapillary architecture, surrounded by an intact myoepithelial cell layer, and were completely intranodal. Of two tumors with tissue available for molecular analysis, one demonstrated a NCOA4-RET fusion and one harbored a STRN-ALK fusion that is novel to IDC. Not only does the intranodal presence of IDC present a challenging differential diagnosis, but the complex nature of this proliferation within lymph node tissue raises questions as to whether the myoepithelial component of IDC is actually non-neoplastic in nature. Furthermore, identification of a STRN-ALK fusion expands the genetic spectrum of IDC and adds to evidence of an emerging role for ALK in salivary gland tumors. Further attention to the nature of the myoepithelial cells and documentation of alternate fusion events in IDC may inform continued discussion about its appropriate classification. 相似文献
7.
Bahram Mohammadi Klaus Krampfl Cener Cetinkaya Heiner Wolfes Reinhard Dengler Johannes Bufler 《Pharmacological research》2005,51(6):587-592
Glycine receptor channels are pentameric ligand-gated ion channels that respond to the application of inhibitory neurotransmitters by opening of a chloride-selective central pore. Topiramate (TPM) is a broad-spectrum antiepileptic drug used as add-on or monotherapy for focal seizures. In the present study the interaction of TPM with glycine receptor channels was studied on outside-out patches from HEK293 cells expressing alpha1beta glycine receptor channels. The patch clamp techniques combined with ultra fast solution exchange enabled us to investigate the kinetics of receptor channels in presence of TPM. Our study showed no agonistic or potentiating effect for TPM on glycine receptor channels. However, in presence of 1 mM glycine + 1 mM TPM, the desensitization got faster and the peak current amplitude decreased. After the end of glycine + TPM pulses, off-currents occurred, suggestive for a specific channel block mechanism. 相似文献
8.
Farhad Shaveisi-Zadeh Bahram Nikkho Mohamaad Bagher Khadem Erfan Amir Amiri Ali Azizi Nasrin Mansouri Mitra Tarlan Zahra Rostami-Far 《The Journal of international medical research》2022,50(7)
ObjectiveCOVID-19 has recently emerged as a serious threat to global health. This study examined the laboratory investigations of patients with COVID-19, with an emphasis on liver enzymes.MethodsThis retrospective, single-center study was performed on patients with COVID-19 who were admitted to Imam Reza Hospital, Iran from March 2020 to February 2021. Laboratory tests included a complete blood cell count, white blood cell (WBC) count, neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), lymphocyte/monocyte ratio, and levels of aspartate aminotransferase, alanine aminotransferase (ALT), and alkaline phosphatase. Patient survival was among the outcome measures investigated in association with laboratory findings.ResultsWe enrolled 77 patients with COVID-19 and 63 healthy controls. In comparison with the control group, patients with COVID-19 showed COVID-19 increased ALT, WBC, neutrophils, NLR, and PLR, and decreased platelet counts and lymphocytes.ConclusionAlthough elevated levels of AST, NLR, PLR, and LMR were found in patients with COVID-19, they were not linked to mortality. Given the presence of AST in other tissues, the influence of SARS-CoV-2 on the liver should be interpreted with caution. 相似文献
9.
Seyed Heydar Mosavi Mirak Seyedmehdi Sharifian Fatemeh Esmaeili Khalil Saraei Neda Asasian-Kolur Bahram Haddadi Christian Jordan Michael Harasek 《Materials》2022,15(13)
Titanium-pillared clay (Ti-PILC), as one of the most suitable types of porous adsorbents/(photo)catalysts, was prepared from a local type of Iranian clay and titanium isopropoxide. The production process was optimized by changing three operating parameters, including the clay suspension concentration (in the range of 0.5–10% w/v), the H+/Ti ratio (2–8 mol/mol), and the calcination temperature (300–700 °C). The largest specific surface area for the Ti-PILC was about 164 m2/g under the clay suspension of 0.5% w/v, H+/Ti = 6, with a surface area 273% larger than that of the raw clay. The surface areas obtained from more concentrated clay suspensions were, however, comparable (159 m2/g for 3% w/v clay and H+/Ti = 4). An increase in the calcination temperature has a negative effect on the porous texture of Ti-PILC, but based on modeling with artificial neural networks, its contribution was only 7%. Clay suspension and H+/Ti ratio play a role of 56 and 37% of the specific surface area. The presence of rutile phase, and in some cases anatase phase of TiO2 crystals was detected. FTIR and SEM investigations of Ti-PILCs produced under different operating parameters were analyzed. 相似文献
10.
Ghizlane Genc İlken Kocadereli Ferda Tasar Kamer Kilinc Sibel El Bahram Sarkarati 《Lasers in medical science》2013,28(1):41-47
The aim of this study is to evaluate the effects of low-level laser therapy (LLLT) on (1) the velocity of orthodontic tooth movement and (2) the nitric oxide levels in gingival crevicular fluid (GCF) during orthodontic treatment. The sample consisted of 20 patients (14 girls, six boys) whose maxillary first premolars were extracted and canines distalized. A gallium-aluminum-arsenide (Ga-Al-As) diode laser was applied on the day 0, and the 3rd, 7th, 14th, 21st, and 28th days when the retraction of the maxillary lateral incisors was initiated. The right maxillary lateral incisors composed the study group (the laser group), whereas the left maxillary lateral incisors served as the control. The teeth in the laser group received a total of ten doses of laser application: five doses from the buccal and five doses from the palatal side (two cervical, one middle, two apical) with an output power of 20 mW and a dose of 0.71 J /cm2. Gingival crevicular fluid samples were obtained on the above-mentioned days, and the nitric oxide levels were analyzed. Bonferroni and repeated measures variant analysis tests were used for statistical analysis with the significance level set at p ≤ 0.05. The application of low-level laser therapy accelerated orthodontic tooth movement significantly; there were no statistically significant changes in the nitric oxide levels of the gingival crevicular fluid during orthodontic treatment. 相似文献