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991.
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Shoulder pain is common among elite swimmers due to the tremendous stress over shoulders during swimming. Supraspinatus muscle is one of the major prime movers and stabilizers of shoulder and is highly susceptible to overloading and tendinopathy. An understanding of the relationship between supraspinatus tendon and pain; and between supraspinatus tendon and strength would assist health care practitioners for developing training regime. The objectives of this study are to evaluate 1) the association between structural abnormality of supraspinatus tendon and shoulder pain and 2) the association between structural abnormality of supraspinatus tendon and shoulder strength. We hypothesized that structural abnormality of supraspinatus tendons positively associated with shoulder pain and negatively associated with shoulder muscle strength among elite swimmers. 44 elite swimmers were recruited from the Hong Kong China Swimming Association. Supraspinatus tendon condition was evaluated using diagnostic ultrasound imaging and shoulder internal and external rotation strength was evaluated by the isokinetic dynamometer. Pearson’s R was used to study the correlation between shoulder pain and supraspinatus tendon condition and to evaluate the association between isokinetic strength of shoulders and supraspinatus tendon condition. 82 shoulders had supraspinatus tendinopathy or tendon tear (93.18%). However, there was no statistically significant association between structural abnormality of supraspinatus tendon and shoulder pain. The results showed that there was no association between supraspinatus tendon abnormality and shoulder pain and there was a significant correlation between left maximal supraspinatus tendon thickness (LMSTT) and left external rotation/ concentric (LER/Con) and left external rotation/ eccentric (LER/Ecc) shoulder strength (p < 0.05) while internal rotation/ external rotation (IR/ER) ratio can also be a significant predicator on LMSTT >6mm (R2 = 0.462, F = 7.016, df = 1, p = 0.038). Structural change of supraspinatus tendon was not associated with shoulder pain, but could be a predictor on MSTT >6mm in elite swimmers. Key points
  • Coaches and practitioners may take advantage of the effectiveness of a single limb body-weight conditioning activity, such as, i.e., alternating leg bounds as a part of pre-competition warm- ups to enhance subsequent performance without needing specific equipment.
  • The effectiveness of conditioning activity exercises appears to be force-vector specific, i.e., vertical drop jumps improve vertical jump performance, while horizontal drop jumps enhance sprint and change of direction performance.
  • The effects of single limb conditioning activity on the contralateral limb have not been thoroughly examined. However, the limited evidence shows that the post-activation performance enhancement effect is mainly local.
Key words: Elite swimmers, supraspinatus tendon abnormality, shoulder pain, isokinetic strength  相似文献   
994.
Germline mutations in the cyclin‐dependent kinase inhibitor, CDKN1B, have been described in patients with multiple endocrine neoplasia (MEN), a cancer predisposition syndrome with adult onset neoplasia and no additional phenotypes. Here, we describe the first human case of CDKN1B deficiency, which recapitulates features of the murine CDKN1B knockout mouse model, including gigantism and neurodevelopmental defects. Decreased mRNA and protein expression of CDKN1B were confirmed in the proband's peripheral blood, which is not seen in MEN syndrome patients. We ascribed the decreased protein level to a maternally derived deletion on chromosome 12p13 encompassing the CDKN1B locus (which reduced mRNA expression) and a de novo allelic variant (c.‐73G>A) in the CDKN1B promoter (which reduced protein translation). We propose a recessive model where decreased dosage of CDKN1B during development in humans results in a neuronal phenotype akin to that described in mice, placing CDKN1B as a candidate gene involved in developmental delay.  相似文献   
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Recently the authors proposed a new staging and grading system for primary biliary cirrhosis (PBC) that takes into account necroinflammatory activity and histological heterogeneity. Herein is proposed a convenient version of this system. Scores for fibrosis, bile duct loss, and chronic cholestasis were combined for staging: stage 1, total score of 0; stage 2, score 1–3; stage 3, score 4–6; and stage 4, score 7–9. Cholangitis activity (CA) and hepatitis activity (HA) were graded as CA0–3, and HA0–3, respectively. Analysis of interobserver agreement was then conducted. Digital images of 62 needle liver biopsy specimens of PBC were recorded as virtual slides on DVDs that were sent to 28 pathologists, including five located overseas. All participants were able to apply this version in all 62 cases. For staging, kappa was 0.385 (fair agreement) and the concordance rate was 63.9%. For necroinflammatory activity, the kappa and concordance rate were 0.110 (slight agreement) and 36.9% for CA, and 0.197 (slight agreement) and 47% for HA, respectively. In conclusion, this new staging and grading system for PBC seems to be more convenient and practical than those used at present, but more instruction and guidance are recommended for the grading of necroinflammatory activity in practice.  相似文献   
999.
Jara‐Lazaro A R, Akhilesh M, Thike A A, Lui P C‐W, Tse G M‐K & Tan P H
(2010) Histopathology 57 , 220–232 Predictors of phyllodes tumours on core biopsy specimens of fibroepithelial neoplasms Aims: To establish histological and biological parameters that can predict phyllodes tumours on core biopsy specimens of indeterminate fibroepithelial neoplasms. Methods and results: Core biopsy specimens of fibroepithelial lesions diagnosed at the Department of Pathology, Singapore General Hospital from 2002 to 2007 were reviewed. Cases in which phyllodes tumour was favoured, or could not be ruled out, were evaluated for stromal cellularity/distribution, nuclear atypia and mitoses, stromal overgrowth, epithelial fronding, epithelial hyperplasia, configuration of lesional edge, presence of pseudoangiomatous stromal hyperplasia and of adipose tissue. Antibodies to Ki67, topoisomerase IIα, CD34, CD117 and Bcl‐2 were applied to sections subjected to immunohistochemistry using the streptavidin–biotin method. Findings were correlated with subsequent excisions. Of 261 core biopsy specimens of fibroepithelial lesions, 98 (37%) comprised cases in which phyllodes tumour could not be excluded and 57 (58%) had subsequent open surgical excisions. Marked stromal hypercellularity (5/5; 100%) and nuclear atypia (1/1; 100%), stromal overgrowth (17/17; 100%), mitoses ≥2/10 high‐power fields (18/18; 100%) and ill‐defined lesional borders (16/16 phyllodes tumours; 100%) were features in core biopsy specimens that exclusively predicted phyllodes tumour on excision. Moderate stromal hypercellularity (20/27 phyllodes tumours; 74%), stromal overgrowth, moderate nuclear atypia (14/16 phyllodes tumours; 87%), pseudoangiomatous stromal hyperplasia (19/23 phyllodes tumours; 83%) significantly correlated with their subsequent excisions. Immunohistochemical markers Ki67 ≥5% and topoisomerase IIα≥5%, and reduced or patchy CD34 on core biopsy specimens correlated significantly with a diagnosis of phyllodes. Conclusions: Stromal hypercellularity, combined with key histological features and immunohistochemical markers Ki67, topoisomerase IIα and CD34, reinforced by clinical findings, can predict phyllodes tumours on core biopsy specimens.  相似文献   
1000.
Relatively high frequency activity (>4 Hz) carries important information about the state of the brain or its response to high frequency events. The electroencephalogram (EEG) is commonly used to study these changes because it possesses high temporal resolution and a good signal-to-noise ratio. However, it provides limited spatial information. Non-invasive fast optical signals (FOS) have been proposed as a neuroimaging tool combining spatial and temporal resolution. Yet, this technique has not been applied to study high frequency brain oscillations because of its relatively low signal-to-noise ratio. Here we investigate the sensitivity of FOS to relatively high-frequency brain oscillations. We measured the steady-state optical response elicited in medial and lateral occipital cortex by checkerboard reversals occurring at 4, 6, and 8 Hz in younger and older adults. Stimulus-dependent oscillations were observed at the predicted stimulation frequency. In addition, in the younger adults the FOS steady-state response was smaller in lateral than medial areas, whereas in the older adults it was reversed in these two cortical regions. This may reflect diminished top-down inhibitory control in the older adults. The results indicate that FOS can be used to study the modulation of relatively high-frequency brain oscillations in adjacent cortical regions.  相似文献   
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