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941.
Noori HR 《Bio Systems》2011,105(3):238-242
Recent experimental studies strongly suggest the influence of glial purinergic transmission in the modulation of synaptic dynamics. By releasing adenosine triphosphate (ATP), which accumulates as adenosine, astrocytes tonically suppressed synaptic transmission. The delayed multi-step feedback of the glial ATP with the neuron suggests the existence of a discrete hysteresis phenomena. By integration of this hysteretic behavior into a delayed leaky integrate-and-fire model for the tripartite synapses, a significant sensitivity of the pre- and postsynaptic firing frequency patterns to the adenosine feedback-delays is observed that might be of importance for adenosine-related neurological deficits, such as sleep disorders. 相似文献
942.
Eimoori Reza Zolala Jafar Pourmohiabadi Hamid Noroozian Ebrahim Mansouri Hakimeh 《Wetlands Ecology and Management》2020,28(3):439-447
Wetlands Ecology and Management - In this research we report the significant effect of the floating water fern Azolla filiculoides on the elimination of hydrazine (N2H4) from water, which is a... 相似文献
943.
Probiotics and Antimicrobial Proteins - In this study, growth performance, body composition, digestive enzymes activity, mucosal and immunological parameters, cultivable bacterial populations, and... 相似文献
944.
BimEL the most abundant Bim splice variant, is subject to ERK1/2-catalysed phosphorylation, which targets it for ubiquitination and proteasome-dependent destruction. In contrast, inactivation of ERK1/2, following withdrawal of survival factors, promotes stabilization of BimEL. It has been proposed that the RING finger protein Cbl binds to BimEL and serves as its E3 ubiquitin ligase. However, this is controversial since most Cbl substrates are tyrosine phosphoproteins and yet BimEL is targeted for destruction by ERK1/2-catalysed serine phosphorylation. Consequently, a role for Cbl could suggest a second pathway for BimEL turnover, regulated by direct tyrosine phosphorylation, or could suggest that BimEL is a coincidence detector, requiring phosphorylation by ERK1/2 and a tyrosine kinase. Here we show that degradation of BimEL does not involve its tyrosine phosphorylation; indeed, BimEL is not a tyrosine phosphoprotein. Furthermore, BimEL fails to interact with Cbl and growth factor-stimulated, ERK1/2-dependent BimEL turnover proceeds normally in Cbl-containing or Cbl−/− fibroblasts. These results indicate that Cbl is not required for ERK1/2-dependent BimEL turnover in fibroblasts and epithelial cells and any role it has in other cell types is likely to be indirect. 相似文献
945.
Asgar Aghaei Hashjin Hamid Ravaghi Dionne S. Kringos Uzor C. Ogbu Claudia Fischer Saeid Reza Azami Niek S. Klazinga 《PloS one》2014,9(1)
Research objective
This study examines the perspectives of a range of key hospital staff on the use, importance, scientific background, availability of data, feasibility of data collection, cost benefit aspects and availability of professional personnel for measurement of quality indicators among Iranian hospitals. The study aims to facilitate the use of quality indicators to improve quality of care in hospitals.Study design
A cross-sectional study was conducted over the period 2009 to 2010. Staff at Iranian hospitals completed a self-administered questionnaire eliciting their views on organizational, clinical process, and outcome (clinical effectiveness, patient safety and patient centeredness) indicators.Population studied
93 hospital frontline staff including hospital/nursing managers, medical doctors, nurses, and quality improvement/medical records officers in 48 general and specialized hospitals in Iran.Principal findings
On average, only 69% of respondents reported using quality indicators in practice at their affiliated hospitals. Respondents varied significantly in their reported use of organizational, clinical process and outcome quality indicators. Overall, clinical process and effectiveness indicators were reported to be least used. The reported use of indicators corresponded with their perceived level of importance. Quality indicators were reported to be used among clinical staff significantly more than among managerial staff. In total, 74% of the respondents reported to use obligatory indicators, while this was 68% for voluntary indicators (p<0.05).Conclusions
There is a general awareness of the importance and usability of quality indicators among hospital staff in Iran, but their use is currently mostly directed towards external accountability purposes. To increase the formative use of quality indicators, creation of a common culture and feeling of shared ownership, alongside an increased uptake of clinical process and effectiveness indicators is needed to support internal quality improvement processes at hospital level. 相似文献946.
947.
Mitchell D Paniker L Sanchez G Bella Z Garaczi E Szell M Hamid Q Kemeny L Koreck A 《Journal of cellular and molecular medicine》2010,14(1-2):313-322
Ultraviolet radiation (UVR) phototherapy is a promising new treatment for inflammatory airway diseases. However, the potential carcinogenic risks associated with this treatment are not well understood. UV-specific DNA photoproducts were used as biomarkers to address this issue. Radioimmunoassay was used to quantify cyclobutane pyrimidine dimers (CPDs) and (6–4) photoproducts in DNA purified from two milieus: nasal mucosa samples from subjects exposed to intranasal phototherapy and human airway (EpiAirway™) and human skin (EpiDerm™) tissue models. Immunohistochemistry was used to detect CPD formation and persistence in human nasal biopsies and human tissue models. In subjects exposed to broadband ultraviolet radiation, DNA damage frequencies were determined prior to as well as immediately after treatment and at increasing times post-treatment. We observed significant levels of DNA damage immediately after treatment and efficient removal of the damage within a few days. No residual damage was observed in human subjects exposed to multiple UVB treatments several weeks after the last treatment. To better understand the molecular response of the nasal epithelium to DNA damage, parallel experiments were conducted in EpiAirway and EpiDerm model systems. Repair rates in these two tissues were very similar and comparable to that observed in human skin. The data suggest that the UV-induced DNA damage response of respiratory epithelia is very similar to that of the human epidermis and that nasal mucosa is able to efficiently repair UVB induced DNA damage. 相似文献
948.
949.
Systematics of the genus Isatis (Brassicaceae) is difficult and controversial, and previous studies were based solely on morphological characters. Sequence variation of the internal transcribed spacer (ITS) regions and the 5.8S gene of nuclear ribosomal DNA (nrDNA) were analyzed using parsimony and Bayesian methods. Twenty-eight taxa of Isatis and related genera of the tribe Isatideae were sampled, including 20 Isatis species representing almost all major morphological lineages, all three species of Pachypterygium, two of nine species of Sameraria, and monospecific Boreava, Myagrum, and Tauscheria. Two well-supported clades were resolved in the ITS tree, and they demonstrate the artificiality of the present delimitation of the tribe. One clade includes I. emarginata, I. minima, I. trachycarpa, P. brevipes, P. multicaule, P. stocksii, and T. lasiocarpa. The second clade includes I. buschiana, the polymorphic I. cappadocica with five subspecies, I. gaubae, I. kotschyana, I. leuconeura, I. pachycarpa, I. takhtajanii, I. tinctoria, and S. armena. Pachypterygium is polyphyletic and, together with Boreava, Sameraria, and Tauscheria, all are nested within Isatis. This study is a continuation of our recent systematic survey based on seed-coat microsculpturing ( Moazzeni et al., 2007. Flora 202, 447–454) and reveals that fruit characters mapped onto the molecular tree show considerable convergence. The reliance on fruit characters alone in the delimitation of genera may well lead to erroneous phylogenetic results and thus to incorrect taxonomic conclusions. 相似文献
950.