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10 patients with major instability symptoms due to an acute anterior cruciate ligament injury were operated on with a bone-patellar tendon-bone reconstruction. Tibial condyle bone mineral density (BMD), bone ingrowth and changes in diameter in the tibia bone tunnel were studied with quantified computed tomography (QCT) postoperatively and after 1, 3, 6 and 12 months. We found no sign of bone ingrowth in the form of increased bone mineral density (BMD) in the bone tunnels in any of the patients. The tunnel diameter increased in all patients during the first postoperative months. After 1 year, 5 patients had a smaller diameter than at the first postoperative examination, 2 had the same diameter as immediately after surgery and 2 patients had a larger diameter. A sclerotic zone developed in all patients along the perimeter of the tunnel during the 3-6 months of follow-up. The BMD in the tibial condyle decreased at 3 months; it then increased, but between 6 and 12 months, it levelled out and was slightly lower than postoperatively. In conclusion, we found no growth of bone into the tunnel and tendinous part of the graft during the first postoperative year.  相似文献   
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The proliferation, cell cycle exit and differentiation of progenitor cells are controlled by several different factors. The chromodomain protein mortality factor 4-like 1 (Morf4l1) has been ascribed a role in both proliferation and differentiation. Little attention has been given to the existence of alternative splice variants of the Morf4l1 mRNA, which encode two Morf41l isoforms: a short isoform (S-Morf4l1) with an intact chromodomain and a long isoform (L-Morf4l1) with an insertion in or in the vicinity of the chromodomain. The aim of this study was to investigate if this alternative splicing has a function during development. We analysed the temporal and spatial distribution of the two mRNAs and over-expressed both isoforms in the developing retina. The results showed that the S-Morf4l1 mRNA is developmentally regulated. Over-expression of S-Morf4l1 using a retrovirus vector produced a clear phenotype with an increase of early-born neurons: retinal ganglion cells, horizontal cells and cone photoreceptor cells. Over-expression of L-Morf4l1 did not produce any distinguishable phenotype. The over-expression of S-Morf4l1 but not L-Morf4l1 also increased apoptosis in the infected regions. Our results suggest that the two Morf4l1 isoforms have different functions during retinogenesis and that Morf4l1 functions are fine-tuned by developmentally regulated alternative splicing. The data also suggest that Morf4l1 contributes to the regulation of cell genesis in the retina.  相似文献   
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The influence of experience in categorizing suspect and occult fractures on radiography compared to MRI and clinical outcome has not been studied. The aim of this study is to evaluate the importance of experience in diagnosing normal or suspect hip radiographs compared to MRI. Primarily reported normal or suspect radiography in 254 patients with low-energy hip trauma and subsequent MRI was re-evaluated by two experienced reviewers. Primary readings and review were compared. The prevalence of fractures among normal and suspect radiographic studies was assessed. Clinical outcome was used as reference. At review of radiography, 44 fractures (17 %) were found. Significantly more fractures were found among suspect cases than among normal cases. At MRI, all 44 fractures were confirmed, and further 64 fractures were detected (25 %). MRI detected all fractures with no missed fractures revealed at follow-up. There were a significantly higher proportion of fractures at MRI among the suspect radiographic diagnoses for both the primary report and at review than among occult cases. The more experienced reviewers classified radiography examinations with higher accuracy than primary reporting general radiologists. There was almost complete agreement on MRI diagnoses.  相似文献   
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Purpose: Two studies are presented that evaluated the Communication Supports Inventory-Children & Youth (CSI-CY), an instrument designed to facilitate the development of communication-related educational goals for students with complex communication needs (CCN). The CSI-CY incorporates a code set based on the ICF-CY. The studies were designed to determine the effect of using the CSI-CY on IEP goals for students with CCN and to evaluate consumer satisfaction.

Method: In Study 1, sixty-one educators and speech–language pathologists were randomly assigned to either (a) provide a student’s current IEP (control group) or (b) complete the CSI-CY prior to preparing a student’s next IEP and to submit the new IEP (experimental group). Study 2 was a field test to generate consumer satisfaction data.

Results: Study 1 showed that IEP goals submitted by participants in the experimental group referenced CSI-CY-related content significantly more frequently than did those submitted by control participants. Study 2 revealed high satisfaction with the instrument.

Conclusions: The code set basis of the CSI-CY extends the common language of the ICF-CY to practical educational use for children with CCN across diagnostic groups. The CSI-CY is well regarded as an instrument to inform the content of communication goals related to CCN.

  • Implications for Rehabilitation
  • The CSI-CY will guide rehabilitation professionals to develop goals for children with complex communication impairments.

  • The CSI-CY is a new instrument that is based on the ICF-CY for documentation of communication goals.

  相似文献   
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Persson H  Ohlin M 《Molecular immunology》2007,44(10):2729-2736
The antigen-binding site, the paratope, of an antibody can be seen as being composed of a central core and a more peripheral area situated at its rim. Naturally these regions acquire their diversity using different mechanisms and they also have dissimilar roles, as they contribute differently to the binding interaction. Also, antigens of different size utilize these regions differently; while haptens mainly interact with the central core, larger antigens have additional interactions in more peripheral regions. Since haptens do not occupy the entire available paratope we hypothesized that hapten-specific antibodies, as they develop naturally or in the laboratory, have an imprint of the carrier protein they were once selected on. By using combinatorial library and phage display technologies on a hapten-specific antibody we were able to demonstrate that a peripheral carrier imprint indeed exists. We further show that such an imprint can act as a seed in the evolution of binders that recognize the carrier protein even in the absence of the hapten modification. The observed results provide a plausible mechanism for how haptenization of self-antigens can lead to the development of autoimmunity.  相似文献   
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