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91.

Purpose

The cervical flexion relaxation phenomenon (FRP) is a neck extensor myoelectric “silence” that occurs during complete cervical and lumbar flexion. In contrast to low back pain, the changes that occur during FRP in chronic neck pain (CNP) patients are still not clear. The aim of this study was to assess the characteristics of this phenomenon in the cervical region in CNP patients and controls.

Methods

Twenty-two women (23 ± 2.62 years) with chronic non-specific neck pain and 21 healthy women (23.4 ± 1.68 years) participated in this study. They accomplished a cervical flexion and extension from neutral position. Neck angle and surface electromyographic activity of cervical erector spinae (CES) and upper trapezius muscles were recorded. Appearance, onset and offset angle of the FRP were analysed and compared between the two groups.

Results

There were significant differences in the appearance of FRP between the two groups (P ≤ 0.001). The FRP in the CES muscles was observed in 85.7 % of healthy subjects and in 36.3 % of CNP patients, and no FRP was observed in the upper trapezius. Results of this study show that the onset and offset of FRP parameters were significantly different between the two groups (P ≤ 0.001).

Conclusions

The results of the present study indicate that FRP in CNP patients was seen less than the healthy subjects, and moreover the FRP period was reduced in CNP patients. Our results also suggest that the changes in FRP of CNP patients may be due to the increased CES activity in these patients.  相似文献   
92.
The radial nerve constitutes a major problem in humeral shaft fractures; it may be injured immediately or during closed reduction or open reduction and internal fixation with plate and screws. After fixation, the nerve always runs directly over the plate without any interposed structure. If a revision surgery is indicated, the nerve is at high risk as it is usually difficult to dissect from surrounding fibrotic scar tissue or callus formation. To avoid these complications, some authors reported transposition of the radial nerve through the fracture line. We present herein the surgical technique of the trans-fracture transposition of the radial nerve during open reduction and internal fixation of humeral shaft fractures, along with our preliminary results in 6 cases and a review of the literature.  相似文献   
93.
The purpose of this study was to examine the effects of the 11+ and HarmoKnee warm-up programs on performance measures in professional soccer players. Thirty-six male professional soccer players (age: 18.9 ± 1.4 years) were divided into 3 groups, the 11+, HarmoKnee and control group (n = 12 per group). The experimental groups performed the programs 3 times per week for 2 months (24 sessions), whereas the control group only performed their regular soccer training. The performance tests carried out were: 10m speed tests with and without a ball, 20m single sprint, vertical jump, Wall-Volley and Illinois agility tests. The 11+ group demonstrated significant increases from pre-to-post time points in the vertical jump (3.7%), Wall- Volley (5.4%) and Illinois agility tests (1.7%), while the HarmoKnee group showed a significant increase in Wall-Volley test, with a 5.2% increase. The repeated measures analysis revealed differences between the groups (large effect size) in the 11+ and HarmoKnee groups, compared to the control group, in 10m speed tests with and without a ball, 20m single sprint and Illinois agility tests (p < 0.05). Thus 8-weeks performing the 11+ warm-up program can enhance jump height, agility and soccer skill while the HarmoKnee program generally only improves soccer skill in young professional male soccer players.

Key Points

  • The 11+ improves performance by means of Illinois agility, vertical jump and Wall-Volley tests whereas HarmoKnee improves Wall-Volley test. Incorporating 11+ as a part of the warm-up program by the young teams would be beneficial in agility, leg power and soccer skill respectively.
  • Further modification of both programs may be required to fully realize the players'' speed performance potential.
  • Data from this research can be helpful for soccer trainers in choosing programs to enhance performances in young male professional soccer players.
Key words: Performance, vertical jump, Illinois agility test, sprint, Wall-Volley test  相似文献   
94.
ObjectiveTo investigate whether miRNA-499 (rs3746444) and miRNA-146a (rs2910164) genes polymorphisms are independent factors for rheumatoid arthritis (RA) in Egyptians, and whether they influence disease severity and activity.MethodsTwo hundred and seventeen RA patients and 245 healthy controls were enrolled in this study. Polymorphisms of miRNA-146a and miRNA-499 genes were detected using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP).ResultsThe miRNA-499 CT genotype was an independent factor of RA. The miRNA-499 CT, CC genotypes and C allele frequencies were significantly increased in erosive RA group. Moreover, the heterozygote CT had more severe and more active form of the disease compared with homozygote CC or TT. However, we did not find any significant association of miRNA-146a polymorphism with RA risk, severity, and activity.ConclusionThe miRNA-499 polymorphism is an independent factor of RA, and influences disease severity and activity.  相似文献   
95.
96.
ObjectivesDespite converging basic scientific and clinical evidence of the link between chronic pain and depression, existing therapies do not often take advantage of this overlap. Here, we provide a critical review of the literature that highlights the intersection in brain networks between chronic low back pain (CLBP) and depression and discuss findings from previous deep brain stimulation (DBS) studies for pain. Based on a multidimensional model of pain processing and the connectivity of the subgenual cingulate cortex (SCC) with areas that are implicated in both CLBP and depression, we propose a novel approach to the treatment of CLBP using DBS of the SCC.Materials and MethodsA narrative review with literature assessment.ResultsCLBP is associated with a shift away from somatosensory representation toward brain regions that mediate emotional processes. There is a high degree of overlap between these regions and those involved in depression, including the anterior cingulate cortex, medial prefrontal cortex, nucleus accumbens, and amygdala. Whereas target sites from previous DBS trials for pain were not anatomically positioned to engage these areas and their associated networks, the SCC is structurally connected to all of these regions as well as others involved in mediating sensory, cognitive, and affective processing in CLBP.ConclusionsCLBP and depression share a common underlying brain network interconnected by the SCC. Current data and novel technology provide an optimal opportunity to develop clinically effective trials of SCC DBS for CLBP.  相似文献   
97.

Objective

To assess competency of urology post-graduate trainees (PGTs) in percutaneous renal access (PCA).

Methods

Upon obtaining ethics approval and informed consents, PGTs between post-graduate years (PGY-3 to PGY-5) from all four urology programs in Québec were recruited. PCA competency of each participant was assessed objectively by performing task 4 on the PERC Mentor? simulator, where they had to correctly access and pop 7 balloons in 7 different renal calyces and subjectively by the validated Percutaneous Nephrolithotomy—Global Rating Scale (PCNL-GRS).

Results

A total of 26 PGTs with a mean age of 29.2 ± 0.7 years participated in this study. When compared with the 21 PGTs without practice, all 5 PGTs who had practiced on the simulator were competent (p = 0.03), performed the task with significantly shorter operative time (13.9 ± 0.7 vs. 4.4 ± 0.4 min; p < 0.001) and fluoroscopy time (9.3 ± 0.6 vs. 3.4 ± 0.4 min; p < 0.001), and had significantly higher PCNL-GRS scores (13 ± 0.6 vs. 20.6 ± 1; p < 0.001) and successful attempts to access renal calyces (23 ± 5 vs. 68.7 ± 11; p = 0.001). According to a pass score of 13/25, thirteen PGTs were competent. Competent PGTs performed the task with significantly shorter fluoroscopy time (9.8 vs. 6.5 min; p = 0.01) and higher percentage of successful attempts to access renal calyces (p < 0.001), higher PCNL-GRS scores (p < 0.001), and lower complications (p = 0.01).

Conclusion

The PCNL-GRS in combination with the PERC Mentor? simulator was able to differentiate between competent and non-competent PGTs.
  相似文献   
98.
The aim of this study was to evaluate the amount of non- and sulfated glycosaminoglycans in the ovariectomized mice uterus, after treatment with ovarian steroids. For this purpose, 50 adult female mice were divided into five groups with 10 animals/each: control group: CG (ovary intact), and ovariectomized groups: OG (vehicle), EG (estradiol), PG (progesterone) and EPG (estradiol combined to progesterone). The treatments started 30 days after ovariectomy. All the animals were treated for 50 consecutive days. These hormones were administered in a sterile oily solution via gavage. Twenty-four hours after the last treatment, all animals were euthanized, removing the uterine horn for biochemical analyses. To quantify, the hyaluronic acid (HA) used ELISA-like fluorometric assay, and the sulfated glycosaminoglycans (GAGs) used agarose gel electrophoresis. The amount of HA was significantly higher in the group treated with progesterone (PG) compared to the others groups (p?p?p?相似文献   
99.
100.
Evidence has accumulated that p53, a prototypical tumor suppressor, may also influence aspects of organismal aging. We have previously described a p53 mutant mouse model, the p53+/m mouse, which is cancer resistant yet exhibits reduced longevity and premature aging phenotypes. p53+/m mice express one full length p53 allele and one truncated p53 allele that is translated into a C-terminal fragment of p53 termed the M protein. The augmented cancer resistance and premature aging phenotypes in the p53+/m mice are consistent with a hyperactive p53 state. To determine how the M protein could increase p53 activity, we examined the M protein in various cellular contexts. Here, we show that embryo fibroblasts from p53+/m mice exhibit reduced proliferation and cell cycle progression compared to embryo fibroblasts from p53+/- mice (with equivalent wild-type p53 dosage). The M protein interacts with wild-type p53, increases its stability, and facilitates its nuclear localization in the absence of stress. Despite increasing p53 stability, the M protein does not disrupt p53-Mdm2 interactions and does not prevent p53 ubiquitination. These results suggest molecular mechanisms by which the M protein could influence the aging and cancer resistance phenotypes in the p53+/m mouse.  相似文献   
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