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151.
Bone mineral content in children 1 to 6 years of age. Detectable sex differences after 4 years of age 总被引:3,自引:0,他引:3
B L Specker W Brazerol R C Tsang R Levin J Searcy J Steichen 《American journal of diseases of children (1960)》1987,141(3):343-344
Age- and sex-specific bone mineral measures have not been available for healthy preschool children. We determined bone mineral content (BMC) and bone width in 89 children 1 to 6 years of age using direct photon absorptiometry at the one-third distal radius site. The BMC increased significantly with age, and bone width increased slightly with age. After stratification by age, male and female children had similar BMC from 1 to 4 years of age, but female children had significantly lower BMC at 5 to 6 years of age. 相似文献
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153.
Liberman RP Hilty DM Drake RE Tsang HW 《Psychiatric services (Washington, D.C.)》2001,52(10):1331-1342
Psychiatric rehabilitation by its very nature is multidisciplinary because of the many competencies required for its implementation. In promoting optimal levels of recovery from schizophrenia and other disabling mental disorders, teams must combine the expert contributions of professionals and paraprofessionals who can individualize a comprehensive array of evidence-based services with competency, consistency, continuity, coordination, collaboration, and fidelity. The authors describe the properties and functions of the multidisciplinary team and key attributes of effective teams. The importance of teams' involving clients, their relatives, and other supporters in setting personally relevant life goals is emphasized. The authors provide examples of the challenges posed by the need to individualize services and of the ways in which barriers to communication and coordination can be overcome. The roles of the various team members are described, including leadership roles and the unique role of the psychiatrist, in the context of newly emerging, evidence-based treatments for psychiatric rehabilitation. 相似文献
154.
Zhang ZG Zhang L Tsang W Goussev A Powers C Ho KL Morris D Smyth SS Coller BS Chopp M 《Brain research》2001,912(2):181-194
Information is lacking regarding dynamic platelet accumulation at the site of the occluded middle cerebral artery (MCA) and the relationship between platelet aggregation in downstream cerebral microvessels and loss of perfusion and vascular integrity of these microvessels. In the present study, we employed a model of embolic MCA occlusion in the rat to simultaneously measure temporal and spatial profiles of platelet accumulation at the site of the embolus occluding the MCA and within downstream cerebral microvessels. We also measured the integrity of microvessels and matrix metalloproteinase (MMP) activity in ischemic brain. Rats (n=36) were subjected to embolic MCA occlusion. Immunohistochemistry was used to detect microvascular integrity, plasminogen activator inhibitor 1 (PAI-1) and the deposition of fibrin. SDS-PAGE zymography was used to measure MMP2 and MMP9 activities. Accumulation of platelets and increases in PAI-1 immunoreactivity at the site of the embolus occluding the MCA were detected 1 h (n=7) and 4 h (n=7) after ischemia, respectively, and numbers of GPIIb/IIIa immunoreactive downstream cerebral microvessels increased significantly (209+/-59; n=7; P<0.05) 4 h after ischemia, suggesting dynamic platelet aggregation. A significant (n=7; P<0.01) diffuse loss of type IV collagen immunoreactivity in microvessels was temporally associated with platelet GPIIb/IIIa immunoreactivity within the vessels. Triple immunostaining revealed that microvessels containing platelet aggregates exhibited loss of type IV collagen immunoreactivity and both intra- and extra-vascular fibrin deposition, suggesting that intravascular platelet aggregation is associated with decreases in the integrity of the microvascular basal lamina and blood-brain barrier leakage. A significant increase (P<0.05) in MMP9 was detected at 4 h (n=3) and 24 h (n=3) after ischemia but levels of MMP2 were not significantly changed in ischemic brain. Our data suggest that dynamic platelet aggregation in ischemic brain may contribute to time-dependent resistance to fibrinolysis. In addition, platelet deposition and increased MMP9 coincided with degradation of type IV collagen and loss of vascular integrity. These data suggest an important role for post-occlusive distal platelet deposition in the pathophysiology of stroke. 相似文献
155.
Hartauer KJ Arbuthnot GN Baertschi SW Johnson RA Luke WD Pearson NG Rickard EC Tingle CA Tsang PK Wiens RE 《Pharmaceutical development and technology》2000,5(3):303-310
The purpose of this study was to identify a degradation product in a tablet formulation of raloxifene hydrochloride (R-HCl), delineate the role of excipients in its formation, and develop a rational strategy for its control. The degradant was identified as an N-oxide derivative of the drug substance based upon spectroscopic characterization and chromatographic comparison to the synthetic N-oxide. To identify the factors contributing to the formation of N-oxide, binary mixtures of each excipient with R-HCl were exposed to 125 degrees C in open containers. Raloxifene hydrochloride underwent an order of magnitude increase in conversion to the N-oxide in the presence of two excipients, povidone and crospovidone, as compared with its conversion in the presence of other excipients. To confirm a hypothesis that peroxide impurities in these two excipients contributed to the oxidation of the drug substance, tablet lots were spiked with quantities of H2O2 equivalent to 200, 400, 600, and 800 ppm peroxide over the intrinsic levels present in povidone and crospovidone. A strong correlation was observed between the total peroxide level and the quantity of the N-oxide formed upon accelerated storage. From these experiments a rational limit test for peroxide content in povidone and crospovidone was adopted as part of a control strategy to limit formation of the degradation product. 相似文献
156.
Yokokawa J Bera TK Palena C Cereda V Remondo C Gulley JL Arlen PM Pastan I Schlom J Tsang KY 《International journal of cancer. Journal international du cancer》2007,121(3):595-605
PAGE4 is an X chromosome-linked cancer testis antigen and is a potential new tumor-associated antigen that is overexpressed in prostate and uterine cancers. The purpose of this study was to identify a human CTL epitope and a corresponding agonist epitope of PAGE4 to determine if PAGE4 is a potential target for vaccine-mediated immunotherapy against PAGE4-expressing tumors. A class I PAGE4 epitope was identified with a high level of binding to HLA-A2. PAGE4 peptide-pulsed dendritic cells were then used to generate human PAGE4-specific T-cell lines. Further studies demonstrated the generation of an enhancer agonist epitope. Compared with the native peptide, the agonist (i) bound to HLA-A2 molecules at lower peptide concentrations, (ii) demonstrated a higher stability of the peptide HLA-A2 complex, (iii) induced higher levels of production of IFN-gamma, Granzyme B, TNF-alpha, IL-2 and lymphotactin by PAGE4-specific T-cell lines and (iv) T-cell lines generated against the agonist peptide were more efficient to lyse HLA-A2 human tumor cells expressing native PAGE4. The studies reported here are the first to describe a PAGE4 CTL epitope and its agonist epitope, and thus identify PAGE4 as a potentially useful target for vaccine-mediated therapy of prostate cancer. 相似文献
157.
Ang JH Man DW 《International journal of rehabilitation research. Internationale Zeitschrift für Rehabilitationsforschung. Revue internationale de recherches de réadaptation》2006,29(4):357-361
The Wolf motor function test is a new time-based method to evaluate upper extremity function both on a joint-specific level and on total limb movements, while performing some functional tasks. The purpose of this paper is to investigate the discriminating power of the Wolf motor function test in classifying individuals with stroke into different levels according to Brunnstrom's stages of recovery. Discriminant analysis was used and the results showed that the Wolf motor function test can classify 86.7% of original grouped cases into the correct groupings. A high correlation was found between the Wolf motor function test, the Brunnstrom stages of recovery and the Fugl-Meyer Assessment. The Wolf motor function test is found to be an instrument capable of discriminating the upper extremity motor function of the individuals with stroke into different functional groups. 相似文献
158.
159.
160.
High-resolution genomic profiling of chromosomal aberrations using Infinium whole-genome genotyping 总被引:21,自引:2,他引:19
Peiffer DA Le JM Steemers FJ Chang W Jenniges T Garcia F Haden K Li J Shaw CA Belmont J Cheung SW Shen RM Barker DL Gunderson KL 《Genome research》2006,16(9):1136-1148
Array-CGH is a powerful tool for the detection of chromosomal aberrations. The introduction of high-density SNP genotyping technology to genomic profiling, termed SNP-CGH, represents a further advance, since simultaneous measurement of both signal intensity variations and changes in allelic composition makes it possible to detect both copy number changes and copy-neutral loss-of-heterozygosity (LOH) events. We demonstrate the utility of SNP-CGH with two Infinium whole-genome genotyping BeadChips, assaying 109,000 and 317,000 SNP loci, to detect chromosomal aberrations in samples bearing constitutional aberrations as well tumor samples at sub-100 kb effective resolution. Detected aberrations include homozygous deletions, hemizygous deletions, copy-neutral LOH, duplications, and amplifications. The statistical ability to detect common aberrations was modeled by analysis of an X chromosome titration model system, and sensitivity was modeled by titration of gDNA from a tumor cell with that of its paired normal cell line. Analysis was facilitated by using a genome browser that plots log ratios of normalized intensities and allelic ratios along the chromosomes. We developed two modes of SNP-CGH analysis, a single sample and a paired sample mode. The single sample mode computes log intensity ratios and allelic ratios by referencing to canonical genotype clusters generated from approximately 120 reference samples, whereas the paired sample mode uses a paired normal reference sample from the same individual. Finally, the two analysis modes are compared and contrasted for their utility in analyzing different types of input gDNA: low input amounts, fragmented gDNA, and Phi29 whole-genome pre-amplified DNA. 相似文献