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Background: We developed a surgical knee rest (SKR) that can be used to decrease the stress placed on the lower half of the body when surgeons work in the standing position. We tested the effectiveness of this device in the context of laparoscopic surgery.

Material and methods: Five healthy, right-handed male surgeons participated, and we recorded surface electromyography (sEMG) signals from the two heads of the left and right gastrocnemius (Gc) muscles during laparoscopic resections of colorectal cancer. The outcome variable was the percentage of maximum Gc muscle effort generated, reported as percent maximal isometric voluntary contraction (%MVC), and this variable was compared between surgeries performed with and without use of the SKR. Assessment covered the first 100?min of surgery, subdivided into two 50-min periods.

Results: Mean %MVC of the left Gc muscle for the full 100-min test period was significantly decreased when the SKR was used (p?=?.027, vs. SKR not used). Notably, mean %MVC of both Gc muscles was significantly decreased during the first 50?min of surgery (p?=?.008 and p?=?.0046).

Conclusion: The SKR is useful for decreasing physical stress incurred by laparoscopic surgeons when working in the standing position.  相似文献   

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We report a case of kerion celsi due to Trichophyton tonsurans. An 18‐year‐old male student judo practitioner had alopecic patches, black dots and subcutaneous abscesses on the right temporal region. The damaged hair represented endothrix infection with T. tonsurans, as assessed by mycological examinations. He was treated with oral itraconazole without any therapeutic effect, followed by terbinafine with good effect. A skin biopsy showed neutrophil, lymphocyte and histiocyte infiltration into the dermis and subcutaneous tissue with abscesses around a number of dilated hair follicles. Immunostaining showed that the expression level of human β‐defensin 2 (HBD‐2) was decreased in the epidermis of the alopecic and adjacent skin. Because interleukin (IL)‐17A generally induces HBD‐2 production by epidermal keratinocytes, we also immunohistochemically investigated IL‐17A expression. Unexpectedly, many IL‐17A‐bearing cells were found around destructed hair follicles, indicating that IL‐17A expression was not attenuated, but rather increased in the skin lesion. Our case suggests that IL‐17A‐upregulated antimicrobial peptide expression is disordered in kerion celsi, and severe inflammation with IL‐17A may cause tissue damage and resultant scar.  相似文献   
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BackgroundDespite proposals and guidelines to prevent baseball injuries in young players by societies and organizations, many shoulder and elbow injuries continue to occur among junior high school baseball players. In order to investigate the training conditions of junior high school baseball players and the risk factors for shoulder and elbow pain in the players, we conducted a questionnaire survey among junior high school baseball players throughout the country.MethodsThe questionnaire survey was conducted among junior high school baseball players in September 2016.ResultsA total of 11,134 junior high school baseball players belonging to 495 teams responded to the survey. Among these, 4004 players trained every day of the week and 1151 players played baseball games every month with no off-season. Among 9752 players who did not have shoulder and/or elbow pain in the spring and summer of 2015, 19.2% of players experienced elbow pain over the course of one year, 13.6% of players experienced shoulder pain, and 28.0% complained of shoulder and/or elbow pain. The frequency of elbow pain was more than that of shoulder pain. At risk for shoulder pain were pitchers and catchers and second-year students, while risk factors for elbow pain were playing pitcher and catcher positions, pitching or throwing ≥300 balls per week, playing ≥10 games on average per month and being left-handed.ConclusionRisk factors for shoulder pain were different from those for elbow pain. To prevent elbow pain, coaches should pay attention to pitchers and catchers and left-handed players and not allow players to pitch or throw ≥300 full-power balls per week or participate in ≥10 games per month. They should also pay attention to pitchers and catchers and second-year students to prevent shoulder pain. It is important for coaches to train multiple pitchers and catchers.  相似文献   
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Purpose:It has been reported previously that intravenously administered gadolinium-based contrast agent (GBCA) leaks into the subarachnoid space around the cortical veins at 4 h after injection in all old people over 37 years, but not in younger people up to 37 years of age in 3D-real IR images. The purpose of this study was to investigate whether there was a strict threshold of 37 years of age for the leakage of the GBCA into the subarachnoid space.Methods:The subjects included 190 patients, that were scanned for 3D-real IR images at 4 hours after intravenous injection of GBCA as a diagnostic test for endolymphatic hydrops. The patient’s age ranged from 14 to 81 years. Two experienced neuroradiologists evaluated the images to determine whether the GBCA leakage around the cortical veins was positive or negative. Any discrepancies between the two observers were discussed and a consensus was obtained.A Mann–Whitney U test and receiver operating characteristic (ROC) curve analysis were used to compare the positive and the negative group and to set the age cut-off value for the prediction of GBCA leakage.Results:The GBCA leakage around the cortical veins was negative in 35 patients and positive in 155 patients. The average age was 33 ± 11 years in the negative group, and 55 ± 12 years in the positive group (P < 0.01). In the ROC analysis for the age and leakage of the GBCA, an area under the curve was 0.905 and the cut-off age was 37.317 years (sensitivity of 0.942 and specificity of 0.771).Conclusion:Intravenously administered GBCA leaks into the subarachnoid space around the cortical veins in most patients over 37 years of age. However, it should be noted that it can be found occasionally in patients under 37 years of age.  相似文献   
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