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41.
Gholami GA Aghaloo M Ghanavati F Amid R Kadkhodazadeh M 《Annals of surgical innovation and research》2012,6(1):3-6
Background
A cursory review of the current socket preservation literatures well depicts the necessity of further esthetic considerations through the corrective procedures of the alveolar ridge upon and post extraction. A new technique has been described here is a rotational pedicle combined epithelialized and connective tissue graft (RPC graft) adjunct with immediate guided tissue regeneration (GBR) procedure.Results
We reviewed this technique through a case report and discuss it??s benefit in compare to other socket preservation procedures.Conclusion
The main advantages of RPC graft would be summarized as follows: stable primary closure during bone remodeling, saving or crating sufficient vestibular depth, making adequate keratinized gingiva on the buccal surface, and being esthetically pleasant. 相似文献42.
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44.
Á. Miklósi Zs. Gonda D. Osorio A. Farzin 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2002,188(2):135-140
It is well known that development of vision is affected by experience, but there are few studies of environmental effects on colour vision. Natural scenes contain predominantly a restricted range of reflectance spectra, so such effects might be important, perhaps biasing visual mechanisms towards common colours. We investigated how the visual environment affects colour preferences of domestic chicks ( Gallus gallus), by training week-old birds to select small food containers distinguished from an achromatic alternative either by an orange or by a greenish-blue colour. Chicks that had been raised in control conditions, with long-wavelength-dominated reflectance spectra, responded more readily to orange than to blue. This was not due to avoidance of blue, as increasing saturation enhanced the chicks' preference for the same hue. The advantage of orange was, however, reduced or abolished for chicks raised in an environment dominated by blue objects. This indicates that responses to coloured food are affected by experience of non-food objects. If colours of ordinary objects in the environment do influence responses to specialised visual signals this might help explain why biological signals directed at birds are often coloured yellow, orange or red; long-wavelength-dominated spectra being more prevalent than short-wavelength-dominated spectra. 相似文献
45.
Structure determinations for 2,2′-bipyridine and 1,10-phenanthroline adducts of lead(II) hexafluoroacetylacetonate, [Pb(bipy)2(hfacac)2] (1), [Pb(bipy)(hfacac)2] (2), and [Pb(phen)(hfacac)2] (3), show that the balance of intermolecular forces within the lattices is seemingly sensitive to the adduct stoichiometry but not to the nature of the heteroaromatic base. In 3, a structure, in which there is an apparent preference for CF/aromatic interactions over separate CF/CF and aromatic/aromatic interactions, is essentially identical at both 120 and 293 K. 相似文献
46.
Premating, not postmating, barriers drive genetic dynamics in experimental hybrid populations of the endangered Sonoran topminnow 总被引:1,自引:0,他引:1
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The timing and pattern of reproductive barrier formation in allopatric populations has received much less attention than the accumulation of reproductive barriers in sympatry. The theory of allopatric speciation suggests that reproductive barriers evolve simply as by-products of overall genetic divergence. However, observations of enhanced premating barriers in allopatric populations suggest that sexual selection driven by intraspecific competition for mates may enhance species-specific signals and accelerate the speciation process. In a previous series of laboratory trials, we examined the strength of premating and postmating barriers in an allopatric species pair of the endangered Sonoran topminnow, Poeciliopsis occidentalis and P. sonoriensis. Behavioral observations provided evidence of asymmetrical assortative mating, while reduced brood sizes and male-biased F(1) sex ratios suggest postmating incompatibilities. Here we examine the combined effects of premating and postmating barriers on the genetic makeup of mixed populations, using cytonuclear genotype frequencies of first- and second-generation offspring. Observed genotype frequencies strongly reflect the directional assortative mating observed in behavioral trials, illustrating how isolating barriers that act earlier in the reproductive cycle will have a greater effect on total reproductive isolation and may be more important to speciation than subsequent postmating reproductive barriers. 相似文献
47.
Michael Tayao Juliana Andrici Mahtab Farzin Adele Clarkson Loretta Sioson Nicole Watson Terence C Chua Tamara Sztynda Jaswinder S Samra Anthony J Gill 《PloS one》2016,11(3)
Background
Pancreatic cancer is both common and highly lethal and therefore new biomarkers or potential targets for treatment are needed. Loss of BRCA associated protein-1 (BAP1) expression has been found in up to a quarter of intrahepatic cholangiocarcinomas. Given the close anatomical relationship between intrahepatic cholangiocarcinoma and pancreatic ductal adenocarcinoma, we therefore sought to investigate the frequency of loss of BAP1 expression in pancreatic ductal adenocarcinoma.Methods
The records of the department of Anatomical Pathology Royal North Shore Hospital, Sydney, Australia, were searched for cases of pancreatic ductal adenocarcinoma diagnosed between 1992 and 2014 with material available in archived formalin fixed paraffin embedded tissue blocks. Immunohistochemistry for BAP1 was performed on tissue microarray sections and if staining was equivocal or negative it was confirmed on whole sections. Negative staining for BAP1 was defined as loss of expression in all neoplastic nuclei, with preserved expression in non-neoplastic cells which acted as an internal positive control.Results
Loss of BAP1 expression was found in only 1 of 306 (0.33%) pancreatic ductal adenocarcinomas. This case was confirmed to demonstrate diffuse loss of expression throughout all neoplastic cells in multiple blocks, consistent with BAP1 loss being an early clonal event. All other cases demonstrated positive expression of BAP1.Conclusion
We conclude that, in contrast to intrahepatic cholangiocarcinoma, loss of expression of BAP1 occurs very rarely in pancreatic ductal adenocarcinoma. Therefore BAP1 inactivation is unlikely to be a frequent driver abnormality in pancreatic adenocarcinoma. 相似文献48.
Leila Farzin Mohammad Esmail Moassesi Fattaneh Sajadi Mojtaba Amiri Hadi Shams 《Biological trace element research》2009,129(1-3):36-45
Zinc (Zn), copper (Cu), and selenium (Se) are well-known as essential trace elements. These elements attract a great interest, not only in the scientific world, but also in the public option. The aim of this study was to evaluate the serum Zn, Cu, and Se levels in healthy volunteers (60 females and 55 males) living in Tehran. The age (6–62 years) and sex of the subjects, as well as drug and tobacco consumption, were registered. The concentrations of these elements were determined by atomic absorption spectrometry. The serum levels of Zn, Cu, and Se in the normal population of Tehran was 0.89?±?0.16 mg/L, 0.95?±?0.20 mg/L, and 99.10?±?21.78 μg/L, respectively. There was no significant gender-related difference in serum Zn concentration (p?<?0.15). However, a significant difference (p?<?0.05) in both Cu and Se levels was observed between males and females. 相似文献
49.
Development of a whole cell vaccine for acute myeloid leukaemia 总被引:1,自引:0,他引:1
Cheuk AT Chan L Czepulkowski B Berger SA Yagita H Okumura K Farzaneh F Mufti GJ Guinn BA 《Cancer immunology, immunotherapy : CII》2006,55(1):68-75
We describe the modification of tumour cells to enhance their capacity to act as antigen presenting cells with particular
focus on the use of costimulatory molecules to do so. We have been involved in the genetic modification of tumour cells to
prepare a whole cell vaccine for nearly a decade and we have a particular interest in acute myeloid leukaemia (AML). AML is
an aggressive and difficult to treat disease, especially, for patients for whom haematopoietic stem cell (HSC) transplant
is not an option. AML patients who have a suitable donor and meet HSC transplant fitness requirements, have a 5-year survival
of 50%; however, for patients with no suitable donor or for who age is a factor, the prognosis is much worse. It is particularly
poor prognosis patients, who are not eligible for HSC transplant, who are likely to benefit most from immunotherapy. It would
be hoped that immunotherapy would be used to clear residual tumour cells in these patients in the first remission following
standard chemotherapy treatments and this will extend the remission and reduce the risk of a second relapse associated with
disease progression and poor mortality rates. In this symposia report, we will focus on whole cell vaccines as an immunotherapeutic
option with particular reference to their use in the treatment of AML. We will aim to provide a brief overview of the latest
data from our group and considerations for the use of this treatment modality in clinical trials for AML.
This article is a symposium paper from the conference “Progress in Vaccination against Cancer 2004 (PIVAC 4)”, held in Freudenstadt-Lauterbad,
Black Forest, Germany, on 22–25 September 2004 相似文献
50.
S Kheradmand Kia E Verbeek E Engelen R Schot RA Poot IF de Coo MH Lequin CJ Poulton F Pourfarzad FG Grosveld A Brehm MC de Wit R Oegema WB Dobyns FW Verheijen GM Mancini 《American journal of human genetics》2012,91(3):533-540
Polymicrogyria is a malformation of the developing cerebral cortex caused by abnormal organization and characterized by many small gyri and fusion of the outer molecular layer. We have identified autosomal-recessive mutations in RTTN, encoding Rotatin, in individuals with bilateral diffuse polymicrogyria from two separate families. Rotatin determines early embryonic axial rotation, as well as anteroposterior and dorsoventral patterning in the mouse. Human Rotatin has recently been identified as a centrosome-associated protein. The Drosophila melanogaster homolog of Rotatin, Ana3, is needed for structural integrity of centrioles and basal bodies and maintenance of sensory neurons. We show that Rotatin colocalizes with the basal bodies at the primary cilium. Cultured fibroblasts from affected individuals have structural abnormalities of the cilia and exhibit downregulation of BMP4, WNT5A, and WNT2B, which are key regulators of cortical patterning and are expressed at the cortical hem, the cortex-organizing center that gives rise to Cajal-Retzius (CR) neurons. Interestingly, we have shown that in mouse embryos, Rotatin colocalizes with CR neurons at the subpial marginal zone. Knockdown experiments in human fibroblasts and neural stem cells confirm a role for RTTN in cilia structure and function. RTTN mutations therefore link aberrant ciliary function to abnormal development and organization of the cortex in human individuals. 相似文献