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Background
Anxiety and depression co-occur in children and adolescents with anxiety commonly preceding depression. Although there is some evidence to suggest that the association between early anxiety and later depression is explained by a shared genetic aetiology, the contribution of environmental factors is less well examined and it is unknown whether anxiety itself is a phenotypic risk factor for later depression. These explanations of the association between early anxiety and later depression were evaluated. 相似文献83.
Wroblewski BM Siney PD Fleming PA 《The Journal of bone and joint surgery. British volume》2003,85(3):376-379
We have prospectively studied the wear of enhanced ultra-high molecular-weight polyethylene (Hylamer) in combination with a zirconia femoral head of 22.225 mm diameter on a cemented, triple-tapered, collarless, polished stem, the C Stem. The 71 patients who underwent total hip arthroplasty had a mean follow-up of six years (3 to 8). No patient died or was lost to follow-up. The clinical results were excellent with 96% of patients satisfied. There were no revisions. Two cups were considered to be loose radiologically. One was avulsed from the cement in a skiing accident, with a periprosthetic fracture of the femur, but has remained stable for more than seven years. One femur shows radiological appearances which are compatible with a healing infection. One femoral component is at risk of loosening. The mean rate of penetration of the cup was 0.22 mm/year (0.06 to 0.55). Our results appear to be within the guidelines set by the National Institute of Clinical Excellence. We have discontinued the use of Hylamer despite excellent clinical results and no revisions to date because the high initial rates of penetration did not settle to the expected low levels within the anticipated time. 相似文献
84.
Bronchial foreign body inhalation is a frequent and potentially serious accident in children. It can provoke long-term complications such as bronchiectasis. These complications occur especially if the delay between inhalation and extraction is long (above 7 days) and in case of vegetal foreign body. To decrease the risk of complications, one must emphasize the importance of early diagnosis and the potential role of fiberoptic bronchoscopy to help the diagnosis in case of suspected inhalation without clinical or radiological signs. Rigid bronchoscopy is the only procedure that allows diagnosis and removal of the foreign body. 相似文献
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Summary Muscules stapedius in guinea pig was investigated with regard to morphology and elemental composition. The muscle fibers are multinucleated, contain a high amount of ribosomes, and a centriole is often found adjacent to the cell nucleus. Intramitochondrial inclusion bodies occur adjacent to cristae mitochondriales. Both type I and type II fibres occur, the latter with all three subtypes. Elemental analysis from the myofibrillar area revealed unexpected low concentration of K and high concentrations of Na, P, and Ca.Supported by grants from the Karolinska Institutet (Matti Anniko) and the Muscle Dystrophy Association (USA) (Romuald Wroblewski) 相似文献
89.
Messer WS Rajeswaran WG Cao Y Zhang HJ el-Assadi AA Dockery C Liske J O'Brien J Williams FE Huang XP Wroblewski ME Nagy PI Peseckis SM 《Pharmaceutica acta Helvetiae》2000,74(2-3):135-140
Cholinergic neurons degenerate in Alzheimer's disease, resulting in cognitive impairments and memory deficits, and drug development efforts have focused on selective M1 muscarinic agonists. 5-(3-Ethyl-1,2,4- oxadiazol-5-yl)-1,4,5,6-tetrahydropyrimidine trifluoroacetic acid (CDD-0102) stimulates M1 muscarinic receptors in rat brain [Messer, W.S., Jr., Abuh, Y.F., Liu, Y., Periyasamy, S., Ngur, D.O., Edgar, M.A., El-Assadi, A.A., Sbeih, S., Dunbar, P.G., Roknich, S., Rho, T., Fang, Z., Ojo, B., Zhang, H., Huzl, J.J., III, Nagy, P.I., 1997a. J. Med. Chem. 40, 1230-1246.] and improves memory function in rats with lesions of the basal forebrain cholinergic system. Moreover, CDD-0102 exhibits oral bioavailability, few side effects and low toxicity, and thus represents a viable candidate for clinical studies. Despite the development of functionally selective agonists such as xanomeline and CDD-0102, there is room for improvements in ligand affinity and selectivity. The high degree of amino acid homology within transmembrane domains has hindered the development of truly selective agonists. Site-directed mutagenesis, biochemical and molecular modeling studies have identified key amino acid residues such as Thr192 and Asn382 in the binding of agonist to M1 receptors [Huang, X.P., Nagy, P.I., Williams, F.E., Peseckis, S.M., Messer, W.S., Jr., 1999. Br. J. Pharmacol. 126, 735-745.]. Recent work has implicated residues at the top of transmembrane domain VI in the binding of muscarinic agonists and activation of M1 receptors [Huang, X.P., Williams, F.E., Peseckis, S.M., Messer, W.S., Jr., 1998. J. Pharmacol. Exp. Ther. 286, 1129-1139.]. Thus, residues such as Ser388 represent molecular targets for the further development of agonists with improved M1 receptor affinity, selectivity and activity. 相似文献
90.
V Aerra M Kuduvalli AN Moloto AK Srinivasan AD Grayson BM Fabri AY Oo 《Journal of cardiothoracic surgery》2006,1(1):6-5