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排序方式: 共有1315条查询结果,搜索用时 15 毫秒
61.
Marian Tsanov Ehsan Chah Richard Reilly Shane M. O'Mara 《The European journal of neuroscience》2014,39(6):957-974
Memory for odour information may result from temporal coupling between the olfactory and hippocampal systems. Respiration defines the frequency of olfactory perception, but how the respiratory rate affects hippocampal oscillations remains poorly understood. The afferent connectivity of the medial septum/diagonal band of Broca complex (MS/DB) proposes this region as a crossroads between respiratory and limbic pathways. Here we investigate if the firing rates of septal neurons integrate respiratory rate signals. We demonstrate that approximately 50% of MS/DB neurons are temporally correlated with sniffing frequency. Moreover, a group of slow‐spiking septal neurons are phase‐locked to the sniffing cycle. We show that inter‐burst intervals of MS/DB theta cells relate to the sniff rate. Intranasal odour infusion evokes sniff phase preference for the activity of fast‐spiking MS/DB neurons. Concurrently, the infusion augments the correlation between sniffing and limbic theta oscillations. During periods of sniffing–theta correlation, CA1 place cells fired preferentially during the inhalation phase, suggesting the theta cycle as a coherent time frame for central olfactory processing. Furthermore, injection of the GABAergic agonist muscimol into medial septum induces a parallel decrease of sniffing and theta frequencies. Our findings provide experimental evidence that MS/DB does not merely generate theta rhythm, but actively integrates sensorimotor stimuli that reflect sniffing rate. Such integration may provide temporal oscillatory synchronisation of MS/DB‐innervated limbic structures with the sniffing cycle. 相似文献
62.
Fahimeh Bagheri Amiri Abbas Sedaghat Ehsan Mostafavi 《Zeitschrift fur Gesundheitswissenschaften》2014,22(5):461-465
Aim
Gender differences among homeless people may affect the frequency of their risky behaviours. This study was conducted to evaluate the behaviour patterns of homeless men and women in Tehran and compare the probable differences.Subject and methods
In this study, 593 homeless people were recruited from five centres that house homeless people in Tehran, the capital city of Iran. A researcher-designed questionnaire was used to study behavioural patterns.Results
In this study, homeless people (513 males and 80 females, all Iranian nationals) were enrolled in the study from June to August 2012. Mean age and mean duration of homelessness among women (35.46 and 12.68 months) were lower than those among men (42.74 and 56.85 months) (p?=?0.001). Although lifetime history of incarceration in men was higher than in women (p?=?0.002), mean duration of imprisonment in the last 10 years in men (21.25 months) and women (17.76 months) was not statistically different (p?=?0.07). Accommodation locality in the past 6 months varied between men and women. Women were current drug users more often than men were (61.53 % versus 45.26 %) (p?=?0.02). The type of drug consumption in women (methamphetamine) differed from that of men (opium and heroin). More men had a history of injecting drugs than did women (30.02 % versus 12.30 %) (p?=?0.003). Condom use at the last sexual encounter was reported to be higher in women compared to men (74.60 % versus 26.62 %) (p?=?0.001).Conclusion
This study showed notable differences in behaviour patterns between homeless men and women and also indicated that homeless people in Tehran exhibit many risky behaviours. 相似文献63.
Marina V. Pryzhkova Indrat Aria Qingsu Cheng Greg M. Harris Xingjie Zan Morteza Gharib Ehsan Jabbarzadeh 《Biomaterials》2014
We investigated the biological response of human pluripotent stem cells (hPSCs) cultured on a carbon nanotube (CNT) array-based substrate with the long term goal to direct hPSC germ layer specification for a wide variety of tissue engineering applications. CNT arrays were fabricated using a chemical vapor deposition system allowing for control over surface roughness and mechanical stiffness. Our results demonstrated that hPSCs readily attach to hydrophilized and extracellular matrix coated CNT arrays. hPSCs cultured as colonies in conditions supporting self-renewal demonstrated the morphology and marker expression of undifferentiated hPSCs. Conditions inducing spontaneous differentiation lead to hPSC commitment to all three embryonic germ layers as assessed by immunostaining and RT-PCR analysis. Strikingly, the physical characteristics of CNT arrays favored mesodermal specification of hPSCs. This is contradictory to the behavior of hPSCs on traditional tissue culture plastic which promotes the development of ectoderm. Altogether, these results demonstrate the potential of CNT arrays to be used in the generation of new platforms that allow for precise control of hPSC differentiation by tuning the characteristics of their physical microenvironment. 相似文献
64.
Using 3D models of bones can highly improve accuracy and reliability of orthopaedic evaluation. However, it may impose excessive computational load. This article proposes a fully automatic method for extracting a compact model of the femur from its 3D model. The proposed method works by extracting a 3D skeleton based on the clinical parameters of the femur. Therefore, in addition to summarizing a 3D model of the bone, the extracted skeleton would preserve important clinical and anatomical information. The proposed method has been applied on 3D models of 10 femurs and the results have been evaluated for different resolutions of data. 相似文献
65.
M. Heidarpour M. Mohri A. H. Fallah-Rad F. Dehghan Shahreza M. Mohammadi 《Comparative clinical pathology》2014,23(1):97-101
The aim of this study was to investigate the treatment-related changes in hematological parameters in dairy cows affected by clinical endometritis (CE) and subclinical endometritis (SE). One hundred seventy postpartum Holstein dairy cows were selected from a large commercial dairy farm. Cows of the SE group presented a significant decrease in PCV (P?<?0.05) and red blood cell (RBC) (P?<?0.05) values, when compared to healthy group, while the CE group presented a significant decrease (P?<?0.01) in PCV and RBC count, when compared to healthy and SE animals. Significant increases in white blood cell (WBC) (P?<?0.05), neutrophil (P?<?0.001), and lymphocyte (P?<?0.001) counts, in the CE and SE groups, were observed when compared to healthy cows. After treatment for CE, PCV and RBC count dropped significantly, whereas WBC, neutrophil, lymphocyte, and monocyte counts decreased significantly (P?<?0.05). In the SE group, WBC, neutrophil, lymphocyte, and monocyte counts decreased significantly after treatment (P?<?0.05). The results obtained in this study confirm endometritis-induced changes in hematological parameter which improve after treatment. 相似文献
66.
67.
Amirhossein Moghanian Roberto Portillo‐Lara Ehsan Shirzaei Sani Hailey Konisky Seyed Hossein Bassir Nasim Annabi 《Journal of tissue engineering and regenerative medicine》2020,14(1):66-81
Orthopedic surgical procedures based on the use of conventional biological graft tissues are often associated with serious post‐operative complications such as immune rejection, bacterial infection, and poor osseointegration. Bioresorbable bone graft substitutes have emerged as attractive alternatives to conventional strategies because they can mimic the composition and mechanical properties of the native bone. Among these, bioactive glasses (BGs) hold great potential to be used as biomaterials for bone tissue engineering owing to their biomimetic composition and high biocompatibility and osteoinductivity. Here, we report the development of a novel composite biomaterial for bone tissue engineering based on the incorporation of a modified strontium‐ and lithium‐doped 58S BG (i.e., BG‐5/5) into gelatin methacryloyl (GelMA) hydrogels. We characterized the physicochemical properties of the BG formulation via different analytical techniques. Composite hydrogels were then prepared by directly adding BG‐5/5 to the GelMA hydrogel precursor, followed by photocrosslinking of the polymeric network via visible light. We characterized the physical, mechanical, and adhesive properties of GelMA/BG‐5/5 composites, as well as their in vitro cytocompatibility and osteoinductivity. In addition, we evaluated the antimicrobial properties of these composites in vitro, using a strain of methicillin‐resistant Staphylococcus Aureus. GelMA/BG‐5/5 composites combined the functional characteristics of the inorganic BG component, with the biocompatibility, biodegradability, and biomimetic composition of the hydrogel network. This novel biomaterial could be used for developing osteoinductive scaffolds or implant surface coatings with intrinsic antimicrobial properties and higher therapeutic efficacy. 相似文献
68.
Abolfazl Mohammadbeigi Shahram Arsang-Jang Ehsan Sharifipour Alireza Koohpaei Mostafa Vahedian Narges Mohammadsalehi Masoud Jafaresmaeili Moharam Karami Siamak Mohebi 《急性病杂志》2021,10(4):150-154,后插1
Objective: To identify the incidence rate, relative risk, hotspot regions and incidence trend of COVID-19 in Qom province, northwest part of Iran in the first s... 相似文献
69.
Farnaz Sepandar Maryam Daneshpazhooh Mahmoud Djalali Hamed Mohammadi Elham Yaghubi Zahra Fakhri Hajar Tavakoli Ehsan Ghaedi Ali Keshavarz Mahnaz Zarei Mohammad Amin Shahrbaf Narges Ghandi Mina Darand Mohamad Hassan Javanbakht 《Phytotherapy research : PTR》2020,34(4):859-866
Pemphigus vulgaris (PV) is a chronic autoimmune disorder with potentially fatal outcomes. The aim of this study was to investigate the effect of l ‐carnitine (LC) on secreted frizzled‐related protein‐5 (SFRP5), omentin, visfatin, and glycemic indices in PV patients under corticosteroid treatment. In this randomized, double‐blind, placebo‐controlled clinical trial, 52 patients with PV were divided randomly into two groups to receive 2 g of LC or a placebo for 8 weeks. Serum levels of SFRP5, omentin, visfatin, and also glycemic indices were evaluated at the baseline and end of the study. LC supplementation significantly decreased the serum level of visfatin (95% CI [?14.718, ?0.877], p = .05) and increased the serum levels of SFRP5 (95%CI [1.637, 11.380], p < .006) and omentin (95% CI [9.014, 65.286], p < .01). However, LC supplementation had no significant effects on the serum levels of glycemic factors such as insulin (95% CI [?1.125, 3.056], p = .426), fasting blood sugar (95% CI [?4.743, 3.642], p = .894), homeostatic model assessment of insulin resistance (95% CI [?0.305, 0.528], p = .729), and quantitative insulin‐sensitivity check index (95% CI [?0.016, ?0.010], p = .81). LC supplementation decreased visfatin serum level and increased omentin‐1 and SFRP5 serum levels in patients with PV. However, it has no significant effect on the serum levels of insulin and glycemic indices. 相似文献
70.
Habiboallah G Nasroallah S Mahdi Z Nasser MS Massoud Z Ehsan BN Mina ZJ Heidar P 《Journal of ethnopharmacology》2008,120(3):335-341