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41.
Yu‐Ching Lin  MD  MSc 《Muscle & nerve》2014,49(6):932-932
Introduction: The aim of this study was to evaluate test feasibility, validity, and reproducibility of the rate of force development scaling factor (RFD‐SF) for the hip muscles. Methods: Feasibility was assessed as the testing compliance, validity as the ability to compute the RFD‐SF from a linear regression, and reproducibility with a test–retest design in 20 healthy subjects. Reliability and agreement (reproducibility) were evaluated using intraclass correlation coefficient (ICC3,1) and percent standard error of measurement (SEM), respectively. Results: The RFD‐SF testing protocol was completed successfully by all subjects, although the analysis had to be modified for hip rotators. Reliability was high (ICC3,1 > 0.70) for all muscles except hip abductors (ICC3,1 = 0.69) and internal rotators (ICC3,1 = 0.58). Agreement was high for all muscles (SEM < 10%). Conclusions: Hip adductor, flexor, and external rotator RFD‐SF can be evaluated with confidence, provided the analysis is modified for external rotators, whereas hip abductor and internal rotator RFD‐SF assessment is not recommended. Muscle Nerve 50: 932–938, 2014  相似文献   
42.
Introduction: We describe the innervation zone (IZ) location in 43 muscles to provide information for appropriate positioning of bipolar electrodes for clinical and research applications. Methods: The IZ was studied in 40 subjects (20 men and 20 women) using multichannel surface electromyography (sEMG). Signal quality was checked visually to identify motor unit action potentials and estimate muscle fiber conduction velocity. Results: Results in 33 muscles were classified as excellent or good, because it was possible to identify an area which is favorable for appropriate positioning of an electrode pair without the need to previously determine the IZ location. Conclusions: Knowledge of IZ location will increase standardization and repeatability of sEMG measures. Muscle Nerve 49 :413–421, 2014  相似文献   
43.
Introduction: We investigated whether muscle endurance differs between IIM patients and controls and if a relationship exists between perceived fatigue and poor muscle endurance. Methods: Quadriceps contractility, measured using femoral nerve stimulation (TwQ), and strength, measured using maximal voluntary contraction (MVCQ), were assessed in 20 IIM patients and matched controls. Quadriceps endurance was assessed using repetitive electrical stimulation (3 minutes). Time for force to fall to 70% initial force was determined (T70). Reported fatigue was measured using the FACIT‐F/Fatigue Severity Scales. Results: TwQ and MVCQ were lower and perceived fatigue greater for patients. There was no difference in T70 between groups. No relationships were observed between perceived fatigue and endurance (T70). Conclusions: IIM patients reported more fatigue and were weaker than controls, but there was no difference in muscle endurance. Endurance and strength were unrelated to reported fatigue measures. Mechanisms driving perceived IIM fatigue are likely to be multifactorial. Muscle Nerve 50 : 401–406, 2014  相似文献   
44.

Purpose

The optimal treatment strategy for ductal carcinoma in situ (DCIS) continues to evolve and should consider the consequences of initial treatment on the likelihood, type, and treatment of recurrences.

Methods

We conducted a retrospective cohort study using two data sources of patients who experienced a recurrence (DCIS or invasive cancer) following breast-conserving surgery (BCS) for index DCIS: patients with an index DCIS diagnosed from 1997 to 2008 at the academic institutions of the National Comprehensive Cancer Network (NCCN; N = 88) and patients with an index DCIS diagnosed from 1990 to 2001 at community-based integrated healthcare delivery sites of the Health Maintenance Organization Cancer Research Network (CRN) (N = 182).

Results

Just under half of local recurrences in both cohorts were invasive cancer. While 40 % of patients in both cohorts underwent mastectomy alone at recurrence, treatment of the remaining patients varied. In the earlier CRN cohort, most other patients underwent repeat BCS (39 %) with only 18 % receiving mastectomy with reconstruction, whereas only 16 % had repeat BCS and 44 % had mastectomy with reconstruction in the NCCN cohort. Compared with patients not treated with radiation, those who received radiation for index DCIS were less likely to undergo repeat BCS (NCCN: 6.6 vs. 37 %, p = 0.001; CRN: 20 vs. 48 %, p = 0.0004) and more likely to experience surgical complications after treatment of recurrence (NCCN: 15 vs. 4 %, p = 0.17; CRN: 40 vs. 25 %, p = 0.09).

Conclusion

We found that treatment of recurrences after BCS and subsequent complications may be affected by the use of radiotherapy for the index DCIS. Initial treatment of DCIS may have long-term implications that should be considered.  相似文献   
45.

Background

Gaps in breast cancer (BC) surgical care have been identified. We have completed a surgeon-directed, iterative project to improve the quality of BC surgery in South-Central Ontario.

Methods

Surgeons performing BC surgery in a single Ontario health region were invited to participate. Interventions included: audit and feedback (A&F) of surgeon-selected quality indicators (QIs), workshops, and tailoring interviews. Workshops and A&F occurred yearly from 2005–2012. QIs included: preoperative imaging; preoperative core biopsy; positive margin rates; specimen orientation labeling; intraoperative specimen radiography of nonpalpable lesions; T1/T2 mastectomy rates; reoperation for positive margins; sentinel lymph node biopsy (SLNB) rates, number of sentinel lymph nodes; and days to receive pathology report. Semistructured tailoring interviews were conducted to identify facilitators and barriers to improved quality. All results were disseminated to all surgeons performing breast surgery in the study region.

Results

Over 6 time periods, 1,828 BC charts were reviewed from 12 hospitals (8 community and 4 academic). Twenty-two to 40 participants attended each workshop. Sustained improvement in rates of positive margins, preoperative core biopsies, specimen orientation labeling, and SLNB were seen. Mastectomy rates and overall axillary staging rates did not change, whereas time to receive pathology report increased. The tailoring interviews concerning positive margins, SLNB, and reoperation for positive margins identified facilitators and barriers relevant to surgeons.

Conclusions

This surgeon-directed, regional project resulted in meaningful improvement in numerous QIs. There was consistent and sustained participation by surgeons, highlighting the importance of integrating the clinicians in a long-term, iterative quality improvement strategy in BC surgery.  相似文献   
46.

Background

Intraoperative cell salvage (IOCS) has been used in musculoskeletal surgery extensively. However, it has never found its place in musculoskeletal oncologic surgery. We have conducted the first-ever study to evaluate the feasibility of IOCS in combination with a leucocyte-depletion filter (LDF) in metastatic spine tumor surgery. This was to pave the path for use of IOCS-LDF in musculoskeletal oncologic surgery.

Methods

Patients with a known primary epithelial tumor, who were offered surgery for metastatic spinal disease, were recruited. Blood samples were collected at three different stages during the surgery: from the operative field before IOCS processing, after IOCS processing, and after IOCS-LDF processing. Three separate samples (5 mL each) were taken at each stage. Samples were examined using immunohistochemical monoclonal antibodies to identify tumor cells of epithelial origin.

Results

Of 30 patients in the study, 6 were excluded for not fulfilling the inclusion criteria, leaving 24 patients. Malignant tumor cells were detected in the samples from the operative field before IOCS processing in eight patients and in the samples from the transfusion bag after IOCS processing in three patients. No viable malignant cell was detectable in any of the blood samples after passage through both IOCS and LDF.

Conclusions

The findings support the notion that the IOCS-LDF combination works effectively in eliminating tumor cells from salvaged blood, so this technique can be applied successfully in spine tumor surgery. This concept can then further be extended to whole musculoskeletal tumor surgery and other oncologic surgeries with further appropriate clinical studies.  相似文献   
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49.
Since the first studies reporting the TP53 p.R337H mutation as founder mutation in Southern and Southeastern Brazil, there has been controversy on its origin. Preliminary analysis of a small subset of Brazilian mutation carriers revealed that the haplotype incided on a Caucasian background. The vast majority of carriers identified today reside in Brazil or, if identified in other countries, are Brazilian immigrants. To our knowledge, the only two exceptions of carriers without a recognizable link with Brazil are two European families, from Portugal and Germany. Haplotype analysis in the Portuguese family revealed the same haplotype identified in Brazilian individuals, but in the German family, a distinct haplotype was found. Knowing that a significant proportion of women with breast cancer (BC) in Southern Brazil are p.R337H carriers, we analyzed p.R337H in a Portuguese cohort of women diagnosed with this disease. Median age at diagnosis among the first 573 patients tested was 60 years and 100 (17.4%) patients had been diagnosed at or under the age of 45 years. Mutation screening failed to identify the mutation in the 573 patients tested. These results are in contrast with the mutation frequency observed in a study including 815 BC‐affected women from Brazil, in which carrier frequencies of 12.1 and 5.1% in pre‐ and postmenopausal women were observed, respectively. These findings suggest that the Brazilian founder mutation p.R337H, the most frequent germline TP53 mutation reported to date, is not a common germline alteration in Portuguese women diagnosed with BC.  相似文献   
50.
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