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81.

Background:

Patellar dislocations are either due to superolateral contracture of the soft tissue or imbalance of the power between the vastus medialis (VM) and the vastus lateralis (VL). The imbalance of muscle power as an etiology of patellar dislocation has not been studied. Hence, we studied the recurrent, habitual and permanent dislocations of the patella with an electromyogram (EMG) of the vastus medialis, vastus lateralis, and pes anserinus, before and after realignment operations, to document the muscle imbalance and effectiveness of the realignment operation.

Materials and Methods:

An electromyographic investigation was carried out on the vastus medialis and vastus lateralis in nine recurrent, 20 habitual, and 13 permanent dislocations of the patella, before and after their realignment operations. Pes anserinus transposition, which acted as a medial stabilizer of the patella, was also investigated with an EMG study, to understand its role on patellar stability at 0°, 30°, 60°, 90°, 120°, 150°, and full flexion of the knee. The age of the patients varied from nine to 30 (mean 15) years. There were 24 males and 18 females. Twenty-six patellar dislocations were on the right and 16 were on the left side.

Results:

Electromyographic pictures reveal subnormal activity of the vastus medialis in all types of dislocations and similar activities of the vastus lateralis in permanent and habitual dislocations recorded pre operatively, which recovered to almost normal values postoperatively, at the mean one-year follow-up. Pes anserinus, which was used for medial stabilization of the patella after its realignment, maintained normal EMG activity before and after the operation.

Conclusion:

This study is significant for understanding the imbalance of muscle activities in patients with an unstable patella, which can be rectified without recurrence after pes anserinus transposition.  相似文献   
82.
Main pancreatic duct (MPD) involvement is a well-demonstrated risk factor for malignancy in intraductal papillary mucinous neoplasm (IPMN). Preoperative radiographic determination of IPMN type is heavily relied upon in oncologic risk stratification. We hypothesized that radiographic assessment of MPD involvement in IPMN is an accurate predictor of pathological MPD involvement. Data regarding all patients undergoing resection for IPMN at a single academic institution between 1992 and 2012 were gathered prospectively. Retrospective analysis of imaging and pathologic data was undertaken. Preoperative classification of IPMN type was based on cross-sectional imaging (MRI/magnetic resonance cholangiopancreatography (MRCP) and/or CT). Three hundred sixty-two patients underwent resection for IPMN. Of these, 334 had complete data for analysis. Of 164 suspected branch duct (BD) IPMN, 34 (20.7 %) demonstrated MPD involvement on final pathology. Of 170 patients with suspicion of MPD involvement, 50 (29.4 %) demonstrated no MPD involvement. Of 34 patients with suspected BD-IPMN who were found to have MPD involvement on pathology, 10 (29.4 %) had invasive carcinoma. Alternatively, 2/50 (4 %) of the patients with suspected MPD involvement who ultimately had isolated BD-IPMN demonstrated invasive carcinoma. Preoperative radiographic IPMN type did not correlate with final pathology in 25 % of the patients. In addition, risk of invasive carcinoma correlates with pathologic presence of MPD involvement.  相似文献   
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Background  

Dysregulation of the hypothalamic–pituitary–adrenal axis is hypothesized to be an important pathway linking socioeconomic position and chronic disease.  相似文献   
85.

Background

Depression is a common symptom in people with multiple sclerosis. We systematically reviewed published controlled trials on the effectiveness of cognitive behavioural therapy (CBT) for the treatment of depression in people with multiple sclerosis.

Methods

Publications were identified using MEDLINE, PsycINFO and the Cochrane Central Register of Controlled Trials to June/July 2013. We combined thesaurus and free-text terms which were synonyms of the concepts multiple sclerosis, depression and cognitive behavioural therapy. We included published controlled trials which compared individual, group CBT, conducted face-to-face or remotely, to no CBT. Two reviewers extracted data to calculate standardized mean differences (SMD) for self-reported symptoms of depression and weighted mean differences (WMD) for the Multiple Sclerosis Impact Scale (MSIS-29), with 95% Confidence Intervals (CIs). We investigated statistical heterogeneity using I2.

Results

Seven eligible studies (n?=?433) were identified, which evaluated the effect on depression of CBT delivered individually (3 studies), in a group (3 studies) and by computer (1 study). The summary effect (SMD -0.61, 95% CI -0.96 to -0.26, p=0.0006) was reduced (SMD -0.46, 95% CI -0.75 to -0.17, p=0.002) when an outlying study was removed in a sensitivity analysis to examine statistical heterogeneity. Three studies (n=213) observed a direction of effect using the MSIS-29 which was not statistically significant (WMD -4.36, 95% CI -9.33 to 0.62, p=0.09). There was no between-subgroup heterogeneity (I2=0).

Conclusions

CBT can be an effective treatment for depression in MS. Further research should explore optimal durations and modalities of treatment for patients with different characteristics.  相似文献   
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Mark AK  高立  杨敏洁 《放射学实践》2006,21(12):1292-1295
青年学者常常在完成资料收集和分析之后对获得的结果充满了激情。然而,在开始写作论文时,这种热情常常锐减。事实也如此,国家级学术会议的论文数远高于最终发表的医学文献数。优秀的研究成果不能发表的原因2大多在于写作新手在开始写作时对写作的认识混乱和畏缩。一般产生畏缩的原因有2个:要么是研究者不知从何着手,要么是不知如何组织文章结构。不过,大部分放射学论文的写作均有规律可寻,在很大程度上是程式化的。本文试图介绍一种可应用于典型放射学论文的逐段写作法。如果初学者能够完成按照本文教授的18段写作,其论文将具有合理的结构,…  相似文献   
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