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941.
Riester A Spyroglou A Neufeld-Cohen A Chen A Beuschlein F 《Journal of molecular endocrinology》2012,48(2):159-167
Urocortin (UCN) 1, 2, and 3 are members of the corticotropin-releasing factor (CRF) family that display varying affinities to the CRF receptor 1 (CRFR1 (CRHR1)) and 2 (CRFR2 (CRHR2)). UCNs represent important modulators of stress responses and are involved in the control of anxiety and related disorders. In addition to the CNS, UCNs and CRFRs are highly expressed in several tissues including the adrenal gland, indicating the presence of UCN-dependent regulatory mechanisms in these peripheral organ systems. Using knockout (KO) mouse models lacking single or multiple Ucn genes, we examined the potential role of the three different Ucns on morphology and function of the adrenal gland. Adrenal morphology was investigated, organ size, cell size, and number were quantified, and growth kinetics were studied by proliferative cell nuclear antigen staining and Ccnd1 expression analysis. Furthermore, mRNA expression of enzymes involved in steroidogenesis and catecholamine synthesis was quantified by real-time PCR. Following this approach, Ucn2, Ucn1/Ucn2 dKO and Ucn1/Ucn2/Ucn3 tKO animals showed a significant cellular hypotrophy of the adrenal cortex and an increase in Ccnd1 expression, whereas in all other genotypes, no changes were observable in comparison to age-matched controls. For steroidogenesis, Ucn2/Ucn3 dKO animals displayed the most pronounced changes, with significant increases in all investigated enzymes, providing indirect evidence for increased stress behavior. Taken together, these data suggest that mainly Ucn2 and Ucn3 could be involved in adrenal stress response regulation while Ucn2 additionally appears to play a role in morphology and growth of the adrenal gland. 相似文献
942.
Cohen R Adini B Radomislensky I Givon A Rivkind AI Peleg K 《World journal of surgery》2012,36(3):539-547
Background
Few studies have investigated whether the presence or absence of attending physicians (AP) in the emergency department (ED) during the management of trauma patients by residents. 相似文献943.
944.
Will J. Eldridge Amihai Meiri Adi Sheinfeld Matthew T. Rinehart Adam Wax 《Biomedical optics express》2014,5(8):2517-2525
We present a fast, wide-field holography system for detecting photothermally excited gold nanospheres with combined quantitative phase imaging. An interferometric photothermal optical lock-in approach (POLI) is shown to improve SNR for detecting nanoparticles (NPs) on multiple substrates, including a monolayer of NPs on a silanized coverslip, and NPs bound to live cells. Furthermore, the set up allowed for co-registered quantitative phase imaging (QPI) to be acquired in an off-axis holographic set-up. An SNR of 103 was obtained for NP-tagging of epidermal growth factor receptor (EGFR) in live cells with a 3 second acquisition, while an SNR of 47 was seen for 20 ms acquisition. An analysis of improvements in SNR due to averaging multiple frames is presented, which suggest that residual photothermal signal can be a limiting factor. The combination of techniques allows for high resolution imaging of cell structure via QPI with the ability to identify receptor expression via POLI.OCIS codes: (160.4236) Nanomaterials, (120.3180) Interferometry, (170.1650) Coherence imaging 相似文献
945.
Ernnie Illyani Basri Mohamed Thariq Hameed Sultan Adi Azriff Basri Faizal Mustapha Kamarul Arifin Ahmad 《Materials》2021,14(13)
A finite element (FE) model is developed to study the structural performance on a composite wing of a UAV with a tubercle design at the leading edge of the wing. The experimental study of the designation of the composite at the wing skin is carried out to prove the simulation validity through material characteristics. In this paper, the numerical modeling for simulation is highlighted to correlate the process parameter setting of simulation replicating the actual experimental tests. The percentage difference was calculated to be 11.1% by tensile and 10.47% by flexural. The numerical work applied the study of FE analysis and developed a standardized numerical approach for structural optimization, known as FE-ACP simulation. The significant findings of deformation are obtained according to Schrenk’s aerodynamic loading, while the prediction of failure mode of Tsai–Wu under interaction among stresses and strains was acquired at the seventh and eighth layer of both spars. 相似文献
946.
Adi Livnat Christos Papadimitriou Jonathan Dushoff Marcus W. Feldman 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(50):19803-19808
The question of what role sex plays in evolution is still open despite decades of research. It has often been assumed that sex should facilitate the increase in fitness. Hence, the fact that it may break down highly favorable genetic combinations has been seen as a problem. Here, we consider an alternative approach. We define a measure that represents the ability of alleles to perform well across different combinations and, using numerical iterations within a classical population-genetic framework, show that selection in the presence of sex favors this ability in a highly robust manner. We also show that the mechanism responsible for this effect has been out of the purview of previous theory, because it operates during the evolutionary transient, and that the breaking down of favorable genetic combinations is an integral part of it. Implications of these results and more to evolutionary theory are discussed. 相似文献
947.
Treatment of deep sternal wound infections post-open heart surgery by application of activated macrophage suspension 总被引:1,自引:0,他引:1
Arie Orenstein MD ; Erez Kachel MD ; Adi Zuloff-Shani PhD ; Yoav Paz MD ; Oren Sarig MD ; Josef haik MD ; Aram K. Smolinsky MD ; Raphael Mohr MD ; Eilat Shinar MD ; David Danon MD 《Wound repair and regeneration》2005,13(3):237-242
Postoperative sternal wound infection remains a significant complication and generally causes considerable morbidity and mortality. Macrophages play a major role in the process of wound healing. In order to evaluate the efficacy of local injection of activated macrophage suspensions into open infected sternal wound space, a retrospective case-control study was conducted. Sixty-six patients with deep sternal wound infection treated by activated macrophages (group 1) and 64 patients with deep sternal wound infection treated by sternal reconstruction surgery with various regional flaps (group 2), were matched for gender, age, and risk index. In up to 54 months of follow-up of group 1, 60 patients (91%) achieved complete wound closure. Two (3%) late deaths occurred unrelated to the procedure. Mortality rate in group 2 was 29.7% (19/64). Duration of hospitalization was 22.6 days in group 1 vs. 56.2 days in group 2. Patients with deep sternal wound infection following open heart surgery that were treated by activated macrophages had significantly less mortality as well as significant reduction of hospitalization in comparison to the surgically treated group. These results illustrate the advantages of using a biologically based activated macrophage treatment. 相似文献
948.
PURPOSE: To report two cases of penetrating keratoplasty using tissue from a donor who had undergone laser-assisted in situ keratomileusis (LASIK) surgery before its transplantation. PARTICIPANTS: Two patients who had penetrating keratoplasties and received donor corneas from eyes that had previous LASIK. INTERVENTION: The two patients underwent corneal transplantation by two different surgeons who were unaware that the donor eyes had previous LASIK treatment. RESULTS: Penetrating keratoplasty was completed without complication in both cases, although a separation of the corneal lamellae was noted during surgery in one of the cases. The two patients are doing well at 5.5 months postsurgery. CONCLUSION: With the increasing popularity of laser refractive surgery, eye banks should increase their awareness and refine screening techniques to rule out refractive surgery in the donor corneas. The long-term follow-up of those patients will reveal if surgical success was compromised by prior refractive surgery. 相似文献
949.
Spiridon Papapetropoulos Nikhil Adi Lina Shehadeh Nanette Bishopric Carlos Singer Andreas A Argyriou Elizabeth Chroni 《Journal of clinical neuroscience》2008,15(9):1027-1030
Mutations in the leucine-rich repeat kinase 2 (LRRK2) gene, especially the G2019S mutation, have been identified as a common cause of Parkinson's disease in southern European and other Mediterranean populations (Iberians, Ashkenazi Jews and North African Arabs). Owing to the geographic and historic vicinity of Greece with areas of high prevalence of LRRK2 mutations we studied the frequency of the G2019S mutation in a well characterized cohort of familial and sporadic Parkinson's disease patients of Greek origin from mainland Greece. The prevalence of the LRRK2 R1441C mutation and the G2385R Asian polymorphism was also determined. We identified no patients with any of the studied mutations/polymorphisms. Very low prevalence of the LRRK2 G2019S mutation has been reported in other southern European populations. LRRK2 mutations appear to be limited in certain populations and differing ancestry and founder effects may explain the reported variability. Accurate estimations of the frequency and penetrance of different LRRK2 mutations are essential for correct and cost-efficient use of genetic testing and proper genetic counseling of patients with Parkinson's disease. 相似文献
950.
A receding chin, colloquially known as a weak chin, is a significant aesthetic impediment to a pleasing face. Multiple techniques exist to evaluate the poorly projecting chin, but most are imprecise when it comes to choosing the proper implant size. This choice is further complicated by the impracticality of commercially available chin implants. Most implant manufacturers offer only three to four categories of implants (small, medium, large, etc) that differ in size from one company to another, making the choice of the proper implant size a real challenge.The present paper discusses a new approach to precise sizing of the chin implant, based primarily on the degree of chin convexity (curvature of the chin pad) in the profile view. Examples of mentoplasties performed using the chin convexity principle are presented. 相似文献