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91.
92.
Extensive resorption of the mandible increases the interarch space and rehabilitation with traditional dentures is often unsatisfactory due to the superficialization of intraoral muscles. A study of 19 patients who underwent augmentation of an atrophic mandible using a bilateral two-step osteotomy and interpositional bone graft technique is presented. Three horizontal bone cuts (one in the intraforamina and two in the molar region) were made and jointed together by two short vertical bone cuts mesialy to the mental nerve. The cranial fragment was lifted and the iliac bone graft was interposed recreating the correct intermaxillary relationship. A broad vascular pedicle was maintained during surgery, ensuring nutrition from the lingual side, essential to reduce resorption of the bone graft and cranial fragment. 141 Biomet 3i Osseotite® implants were placed. Patients were rehabilitated with a full-arch implant-supported fixed prosthesis or an implant-supported overdenture. This clinical study describes the resorption process over a 4 year follow-up. 3 of 19 suffered from persistent neurosensitive disturbances. In conclusion, bilateral two-step osteotomy in association with interpositional bone graft is a reliable surgical means to recreate the anatomical morphology of the mandible.  相似文献   
93.
Dermanyssus gallinae (Arthropoda, Mesostigmata) is suspected to be involved in the transmission of a wide variety of pathogens, but nothing is known about its associated non-pathogenic bacterial community. To address this question, we examined the composition of bacterial communities in D. gallinae collected from standard poultry farms in Brittany, France. Genetic fingerprints of bacterial communities were generated by temporal temperature gradient gel electrophoresis (TTGE) separation of individual polymerase chain reaction (PCR)-amplified 16S rRNA gene fragments, followed by DNA sequence analysis. Most of the sequences belonged to the Proteobacteria and Firmicute phyla, with a majority of sequences corresponding to the Enterobacteriales order and the Staphylococcus genus. By using statistical analysis, we showed differences in biodiversity between poultry farms. We also determined the major phylotypes that compose the characteristic microbiota associated with D. gallinae. Saprophytes, opportunistic pathogens and pathogenic agents such as Pasteurella multocida, Erysipelothrix rhusiopathiae and sequences close to the genus Aerococcus were identified. Endosymbionts such as Schineria sp., Spiroplasma sp. Anistosticta, “Candidatus Cardinium hertigii” and Rickettsiella sp. were also present in the subdominant bacterial community. Identification of potential targets within the symbiont community may be considered in the future as a means of ectoparasite control.  相似文献   
94.
Allogeneic bone marrow transplant (BMT) or hematopoietic stem cell transplant (HSCT) is one of the most arduous cancer treatments to endure and is therefore likely to have more long-term sequelae. The aim of this article is to discuss and analyze the results of international scientific articles on the psychological impact of HSCT, based on psychoanalytic concepts. We focus on the concepts of psychosocial distress, quality of life (QOL), posttraumatic stress disorder (PTSD) and posttraumatic growth (PTG).  相似文献   
95.
Pleural effusion is increasingly reported in children. Standard culture of blood or pleural fluid is frequently negative and molecular diagnosis by polymerase chain reaction is not available in all hospitals. The Binax NOW Streptococcus pneumoniae Antigen test (Binax, Portland, USA) is a rapid immunochromatographic test (ICT) for the detection of the C polysaccharide antigen. We evaluated the Binax NOW test on the pleural fluid of 73 children hospitalized with pleural effusion over a period of 4 years. In our sample, the sensitivity and specificity of ICT were high (88% and 71%, respectively), with a positive predictive value of 96%. Detection of the pneumococcal antigen in pleural fluid by ICT is easy and quick, and enables us to identify the pneumococcal origin of the effusion, thus, making the treatment of complicated pneumonia suitably and early.  相似文献   
96.
CK2 is a pleiotropic, ubiquitous, and constitutively active protein kinase (PK), with both cytosolic and nuclear localization in most mammalian cells. The holoenzyme is generally composed of two catalytic (α and/or α′) and two regulatory (β) subunits, but the free α/α′ subunits are catalytically active by themselves and can be present in cells under some circumstances. CK2 catalyzes the phosphorylation of more than 300 substrates characterized by multiple acidic residues surrounding the phosphor‐acceptor amino acid, and, consequently, it plays a key role in several physiological and pathological processes. But how can one kinase orchestrate all these tasks faithfully? How is it possible that one kinase can, despite all pleiotropic characteristics of PKs in general, be involved in so many different biochemical events? Is CK2 a druggable target? Several questions are still to be clearly answered, and this review is an occasion for a fruitful discussion. © 2009 Wiley Periodicals, Inc. Med Res Rev, 30, No. 3, 419–462, 2010  相似文献   
97.
Organochalcogens are important intermediates and useful reagents in organic synthesis. Recent data from our laboratory demonstrated that bis and tris-selenide alkene derivatives are attractive synthetic targets because of their chemio-, regio- and stereo-selective reactions. Since the erythrocytic delta-aminolevulinate dehydratase (delta-ALA-D) activity could be an important indicator of toxicity, this report investigated bis and tris-selenide alkene derivatives effects on blood delta-ALA-D in vitro. To investigate the mechanisms by which these compounds inhibit human blood delta-ALA-D activity, a thiol reducing agent or zinc chloride were used. 1,2-Bis-selenide alkene derivatives 1a (R=4-MeOC(6)H(4)), 1b (R=4-ClC(6)H(4)) and 1c (R=2,4,6-Me(3)C(6)H(2)) did not inhibit human blood delta-ALA-D activity. 1,1,2-Tris-selenide alkene derivative 2a (R=C(6)H(5)) was the most potent delta-ALA-D inhibitor. Compounds 2b (R=4-MeOC(6)H(4)) and 2c (R=4-ClC(6)H(4)) displayed similar inhibitory potency towards delta-ALA-D activity. Dithiothreitol, a hydrophobic SH-reducing agent, was able to restore and to protect delta-ALA-D activity inhibited by tris-selenide alkene derivatives. Conversely, ZnCl(2) did not alter the enzyme inhibition induced by tris-selenide alkene derivatives. From these findings we suggest that 1,1,2-tris-selenide alkene derivatives inhibited delta-ALA-D activity by an interaction with essential sulfhydryl groups for the enzyme activity.  相似文献   
98.
99.
Chromatin restricts the accessibility of DNA to regulatory factors; its remodeling over the regulatory regions contributes to the control of gene expression. An increasing number of evidence links defects in chromatin remodeling machinery and cancer. Our aim is to elucidate the role of chromatin structure in the control of the expression of hormone-induced genes in breast cell lines estrogen-dependent or -independent for growth. Mammary tumor growth is controlled by steroid hormones via their nuclear receptor and by growth factors via tyrosine kinase receptors. 50 % of these tumors elude to hormonal control. This limits the anti-estrogen therapy. As a model, we have analyzed in several cell lines the chromatin organization of the regulatory regions of two genes, pS2 that is associated with a good prognostic, and cathepsin D (catD) that is a bad prognostic marker. The expression of the two genes is estrogen-regulated in estrogen-dependent cell line MCF7. In contrast in the hormone-independent cell line MDA MB 231, pS2 is not expressed and catD is constitutively expressed. Within the regulatory regions of pS2 gene, we have localized two regions that undergo a hormone-dependent change in chromatin structure in MCF7 cells but not in MDA MB 231. The lack of chromatin remodeling in MDA MB 231 cells is not due to the absence of expression of the estrogen receptor in the cell line. The expression of pS2 gene can be correlated with chromatin remodeling over the regulatory regions of pS2 gene. In contrast catD regulatory regions did not display hormone-dependent changes in chromatin structure, suggesting that hormone regulation takes place within regions with a constitutively open chromatin structure.  相似文献   
100.
The clinical importance of the measurement of bone mineral content (BMC) in fullterm infants by photon absorptiometry relies on a comparatively narrow normative range that is necessary requisite to interpret the data from a single child. In the attempt to reduce the artifactual scattering of data, it was undertaken a normative study to control all variables that might affect BMC at birth. Thus, growth parameters and birth season (as an index of maternal vit. D status) were related to BMC, Bone Width (BW) and the considered growth parameters did not show any significant difference related to sex and birth season. Thus, all data were analyzed together. It appears that BMC at birth in fullterm infants averaged 92.2 +/- 14.6 mg/cm. BMC did not correlate with skeletal length, crown length and gestational age in the considered range. Conversely, significant correlation were found between BMC and BW and between BMC and body weight. We conclude that: a) birth season and sex do not affect bone mineralization in fullterm infants, b) any comparison among BMC should be established within populations homogeneous for weight and BW.  相似文献   
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