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Surgical treatments for chronic, painful hallux sesamoid disorders typically involve partial or complete resection of 1 or both sesamoids. Although these approaches generally result in satisfactory symptom relief, their effect on biomechanical function of the major hallux flexors is not completely understood. The effects of selective sesamoid resections on the effective tendon moment arm of the flexor hallucis longus tendon were evaluated. Twelve fresh frozen cadaver first rays were each mounted in a device that held rigid the metatarsal. A ramp-controlled displacement of an MTS ram supplied a functional load input force to the flexor hallucis longus. The components of the resultant output force necessary to resist the input flexor hallucis longus force were transduced simultaneously by a multicomponent load cell. Subsequently, 3 progressively more extensive seasamoid resections were done: (1) distal hemiresection, (2) complete resection, and (3) resection of both sesamoids. Six specimens were tested with the medial sesamoid removed first and 6 with the lateral sesamoid removed first. Statistical analysis showed that significant decreases in the effective tendon moment arms occurred with full medial sesamoid resection, full lateral sesamoid resection, and resection of both the medial and lateral sesamoids. 相似文献
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RW Mann ME Feather CS Tumosa TD Holland KN Schneider 《Canadian Metallurgical Quarterly》1998,97(2-3):79-86
We review and present current evidence supporting independent regulation of nuclear Ca2+ ([Ca2+]n). The nucleus and nuclear envelope contain proteins to both regulate and respond to changes in [Ca2+]n. However, this does not prove that [Ca2+]n is independently regulated from cytosolic Ca2+ ([Ca2+]c). Studies using fluorescent dyes suggested that changes in [Ca2+]n differed in magnitude from changes in [Ca2+]c. These studies have been criticised as the nuclear environment alters the fluorescent characteristics of these dyes. We have evaluated this question with aequorin targeted to the nucleus and cytoplasm and shown that the characteristics of the indicators are not altered in their respective environments. We have demonstrated that different stimuli induce changes in [Ca2+]n and [Ca2+]c that vary both temporally and in magnitude. The nucleus appeared to be shielded from increases in [Ca2+]c, either through a mechanism involving the nuclear envelope or by cytosolic buffering of localised increases in Ca2+. In addition, agonist stimulation resulted in an increase in [Ca2+]n, consistent with release from the perinuclear Ca2+ store. There was a stimulus dependence of the relation between [Ca2+]n and [Ca2+]c suggesting differential regulation of [Ca2+]n. These results have important implications for the role of Ca2+ as a specific regulator of nuclear events through Ca2+ binding proteins. In addition, they highlight the advantages of using targeted aequorin in intact cells to monitor changes in organelle [Ca2+]. 相似文献
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A number of biochemical and haematological parameters, including plasma electrolytes, parameters of hepatic and renal function, plasma enzymes and free fatty acids were measured in 13 athletes before and after a 160-km 24-hour race. The runners were divided into 2 groups: group A, who competed the 160 km within 24 hours and group B, who either ran for 24 hours, or who retired before completing the distance. Minimal changes were found in the plasma electrolyte patterns in either group, whereas blood urea and creatinine levels increased during the race. The plasma enzymes increased to varying extents, the greatest increases being in lactic dehydrogenase, aspartate aminotransferase and the skeletal muscle specific MM isoenzyme of creatinine phosphokinase. Total bilirubin also increased, but no conclusive evidence of hepatic decompensation was found. Plasma free fatty acids levels were very markedly raised in 12 of the runners, the highest increases occurring in group A. All runners ingested carbohydrate during the race and this probably explains why the blood glucose levels increased slightly but remained within normal limits in all the athletes at the end of the race. 相似文献
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TD Manners 《Canadian Metallurgical Quarterly》1998,29(7):570-574
A 66-year-old female had ischemic heart disease due to left main lesion complicated with calcified ascending aorta, right pelvic carcinoma and liver cirrhosis. The combined operations with coronary artery bypass by left internal thoracic artery under the hypothermic ventricular fibrillation with cardiopulmonary bypass and right nephrectomy were performed successfully. Postoperatively Treadmill exercise test and scintigram revealed no ischemihc change. She is doing well. The aortocoronary bypass to left anterior descending artery using a left internal thoracic artery under hypothermic ventricular fibrillation with cardiopulmonary bypass might be one of surgical options for high risk patient. 相似文献