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An enzyme linked assay system was used to quantitate platelet associated IgM (PAIgM) in addition to platelet associated IgG (PAIgG) in normal subjects and in 145 patients with autoimmune thrombocytopenia (AITP). The mean PAIgM level in normals was 1.17 ng/10(6) platelets with a range of 0.01-2.45 ng (mean +/- 2 SD). The corresponding PAIgG values as follows: mean 6.0 ng, range 2.0-10 ng/10(6) platelets. Elevated PAIgG was seen in 67.6% and abnormally raised PAIgM in 79.3% of patients. Both values were raised together in 57.2% and either elevated PAIgG or PAIgM in 89.7%. All patients with PAIgG values greater than 4 times upper limit of normality were found to have abnormal PAIgM. The relevance of elevated PAIgM, the possible interaction between PAIgG and PAIgM and the implication of our results in patients with autoimmune thrombocytopenia are discussed.  相似文献   
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Three‐dimensional analysis of wrist motion is a growing focus in orthopedic research, however, our understanding of its validity (accuracy and reliability) remains limited. Nine human cadavers were tested to estimate wrist joint axes alignment in a postural static pose. The objective was to investigate a rater's ability to reliably align three skin‐ tracked wrist joint coordinate system (WJCS) definitions across baseline and reconstructive wrist states (intact, mid‐carpal arthrodesis, and proximal‐row carpectomy). Two WJCSs (legacy, anatomic) were based on palpated bony landmarks and the third (functional) was based on both landmarks and passive flexion‐extension motion. A coordinate frame based on the anatomic definition was tracked with bone pins and served as a reference. Each WJCS was tested in each wrist state and in three forearm position (45° pronation, neutral, 45° supination). The angular offset about each axis of the WJCS frames were calculated with respect to the reference in flexion‐extension, radial‐ulnar deviation, and pronation‐supination for every iteration. Reliability and root mean square deviation values were analyzed across wrist states. Our data suggest that no WJCS is uniformly more reliable than another. The functional WJCS definition was most consistent across intact and post‐operative states for pronation‐supination offset, but this was dependent on rater interpretation. It still however offers the practical benefit of requiring fewer landmarks. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1341–1347, 2015.  相似文献   
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Background

International sports programs have established pre‐participation athletic screening procedures as an essential component to identify athletes that are at a high risk of becoming injured. The Functional Movement Screen (FMS™) is a screening instrument intended to evaluate deficiencies in the mobility and stability of an athlete that might be linked to injury. To date, there are no published normative values for the FMS™ in adolescent school aged children. The purpose of this study was to establish normative values for the FMS™ in adolescent school aged children (10 to 17 years). Secondary aims were to investigate whether the performance differed between boys and girls and between those with or without previous history of injury.

Methods

1005 adolescent school students, including both males and females between the ages of 10 and 17 years who fulfilled the inclusion and exclusion criteria, were selected for the study. The test administration procedures, instructions and scoring process associated with the standardized version of the test were followed in order to ensure accuracy in scoring. The components of the FMS™ include the deep squat, hurdle step, in‐line lunge, shoulder mobility, active straight leg raise, trunk stability push up, and rotary stability.

Results

The mean composite FMS™ score was 14.59 (CI 14.43 ‐ 14.74) out of a possible total of 21. There was a statistically significant difference in scores between females and males (p= .000). But no statistically significant difference in scores existed between those who reported a previous injury and those who did not report previous injury (p=.300). The variables like age (r= ‐.038, p=.225), height(r= .065, p= .040), weight (r=.103, p=.001) did not show a strong correlations with the mean composite score.

Conclusion

This study provides normative values for the FMS™ in adolescent school aged children, which could assist in evaluation of functional mobility and stability in this population.

Level of evidence

2c  相似文献   
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Although stem cell populations mediate regeneration of rapid turnover tissues, such as skin, blood, and gut, a stem cell reservoir has not been identified for some slower turnover tissues, such as the pancreatic islet. Despite lacking identifiable stem cells, murine pancreatic β cell number expands in response to an increase in insulin demand. Lineage tracing shows that new β cells are generated from proliferation of mature, differentiated β cells; however, the mechanism by which these mature cells sense systemic insulin demand and initiate a proliferative response remains unknown. Here, we identified the β cell unfolded protein response (UPR), which senses insulin production, as a regulator of β cell proliferation. Using genetic and physiologic models, we determined that among the population of β cells, those with an active UPR are more likely to proliferate. Moreover, subthreshold endoplasmic reticulum stress (ER stress) drove insulin demand–induced β cell proliferation, through activation of ATF6. We also confirmed that the UPR regulates proliferation of human β cells, suggesting that therapeutic UPR modulation has potential to expand β cell mass in people at risk for diabetes. Together, this work defines a stem cell–independent model of tissue homeostasis, in which differentiated secretory cells use the UPR sensor to adapt organ size to meet demand.  相似文献   
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