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The overtraining syndrome is a chronic fatiguing illness that affects highly motivated endurance athletes. It is characterized by declining performance when maintaining a normal training program. The cause seems to be failure of adaptation within the neuroendocrine system, due to inadequate periods of rest. The onset is insidious and unfortunately, once it manifests, the only treatment is rest. This article discusses the known pathophysiology of overtraining, along with practical aspects of evaluation and treatment.  相似文献   
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The most common causes of hyperthyroidism are Graves' disease, toxic nodular goiter, and iodine-induced hyperthyroidism. Hyperthyroidism can be treated medically with antithyroid drugs or radioactive iodine, or surgically. Multiple clinical factors must be weighed when choosing a treatment modality. All of the available forms of therapy have advantages and disadvantages, and treatment choices must be individualized.  相似文献   
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HYPOTHESIS: Carotid angioplasty and stenting seems to have equal or better outcomes in high-risk patients than carotid endarterectomy. DESIGN: Single-center case-control study. SETTING: University hospital tertiary referral center. PATIENTS: Individuals (n = 53) undergoing elective carotid angioplasty and stenting for cervical carotid stenosis (n = 57) between April 2001 and October 2003. All patients were referred to and treated by the primary author (M.K.E.). RESULTS: Mean +/- SD age was 68.8 +/- 1.2 years (64% men [34] and 36% women [19]), and overall mean +/- SD rate of stenosis was 79% +/- 10%. Preprocedural neurologic symptoms were present in 42% of the group. Indications for treatment included prior neck surgery with irradiation (4), recurrent stenosis (19), and severe comorbidities (34). Duplex scanning 24 hours after stenting showed immediate mean percentage reductions in peaksystolic velocity and end diastolic velocity of 74% and 76%, respectively. After a 30-day follow-up period, there were no deaths and no major or minor strokes. One patient (1.7%) developed transient amaurosis fugax 12 hours after the procedure. Four patients (7.0%) experienced access-related complications. Intraoperative complications included 1 seizure (1.7%) and 1 asystolic arrest (1.7%), both treated successfully. During follow-up, 3 cases of re-stenosis (5.0%) occurred. One asymptomatic occlusion (1.7%) was detected at the 6-month follow-up visit. There have been no late carotid-related complications or deaths. CONCLUSIONS: Vascular surgeons possessing advanced catheter-based skills can safely perform carotid angioplasty and stenting and can achieve perioperative results comparable with carotid endarterectomy. Determination of the true efficacy and durability of carotid angioplasty and stenting as compared with endarterectomy awaits ongoing randomized national trials.  相似文献   
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OBJECTIVE: Vascular remodeling in response to injury or low shear stress (or both) is characterized by neointimal hyperplasia and luminal contraction. When profound, the response leads to restenosis after percutaneous endovascular intervention as well as to de novo stenosis in vein grafts. It has recently been reported that exposure of vein patches to neurovirulence-attenuated Herpes simplex virus-1 (HSV-1) decreases neointimal hyperplasia and increases luminal area. This experiment tested the hypothesis that R7020, a more highly attenuated mutant of HSV-1, would modulate the vascular remodeling response of experimental vein grafts chronically exposed to low shear stress. METHODS: The external jugular veins of 31 New Zealand white rabbits were clamped and intraluminally exposed to vehicle (phospate-buffered saline solution, n = 11), R7020 2.5 x 10(8) plaque forming units [PFU]/mL (n = 8), or R7020 2.5 x 10(9) PFU/mL (n = 12) for 10 or 30 minutes at an average pressure of 80 mm Hg. After exposure, an end-to-side distal external jugular-to-common carotid artery anastomosis was created, resulting in a widely patent arteriovenous fistula. The external jugular was suture-ligated just proximal to the thoracic inlet, distal to a small 10- to 50-microm venous tributary, creating a reversed vein "graft" segment immediately and abruptly exposed to arterial pressure (48 +/- 3 mm Hg) and low shear stress (0.12 +/- .02 dyne/cm(2)). In the 29 animals (N = 31) that survived to harvest, 26 grafts were found to be patent and were analyzed further. Nine grafts were harvested within the first week after operation, snap frozen in liquid nitrogen, and assayed for the presence of the Herpes viral immediate-response protein ICP0 by Western blot analysis. The 17 remaining grafts were perfusion-fixed, excised, stained, and analyzed morphometrically by digital planimetry. RESULTS: In patent grafts, the hemodynamic environment of low shear stress was maintained (shear stress at harvest, 0.26 +/- .06 dyne/cm(2)). Western blot analysis revealed the presence of ICP0 in R7020-exposed vein grafts after 2, 3, 7, and 14 days; ICP0 was not detected in unexposed vein grafts or adjacent carotid arteries. After 4 weeks, vein grafts exposed to R7020 exhibited a statistically significantly increased ratio of luminal radius to wall thickness, indicating altered remodeling (vehicle, 6.7 +/- 1.3; R7020 2.5 x 10(8), 9.1 +/- 1.3; R7020 2.5 x 10(9) ratio, 11.3 +/- 1.4; P < .05 for high dose compared with vehicle). CONCLUSION: A brief exposure of the neurovirulence-attenuated HSV-1 strain R7020 results in an increased ratio of luminal radius to wall thickness in experimental vein grafts chronically exposed to low shear stress.  相似文献   
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OBJECTIVES: This study was designed to describe the fracture patterns and early results of treatment of posterior shearing tibial plateau fractures. DESIGN: Retrospective case series. SETTING: Tertiary care hospital. PATIENTS: Thirteen patients identified from prospective trauma database with posterior shearing tibial plateau fractures. INTERVENTION: Open reduction and internal fixation through a posterior approach to the knee. MAIN OUTCOME MEASUREMENTS: Functional outcome assessed by Musculoskeletal Functional Assessment score and Visual Analogue Scale pain scores. Clinical and radiographic outcome. RESULTS: A consistent fracture pattern was identified with a primary, inferiorly displaced posteromedial shear fracture with variable amounts of lateral condylar impaction. The average duration of clinical patient follow-up was 20 (range, 13-27) months. All fractures healed after index surgery. Two complications (1 wound dehiscence and 1 flexion contracture) were all managed nonoperatively. Three independent surgeons graded patients' articular reduction, with good interobserver reliability (intraclass correlation coefficient = 0.82). The average Musculoskeletal Function Assessment dysfunction score for the 9 patients who responded was 19.5/100, and average resting Visual Analogue Scale pain score was 1.8 cm/10 cm, indicating good function. The functional outcome score was significantly related to the quality of articular reduction (P < 0.017, R = 0.456). CONCLUSIONS: Posterior shearing tibial plateau fractures form a consistent pattern. They can be successfully managed using a posterior approach with direct reduction and buttress fixation of articular fragments. Quality of articular reduction is one factor that influences short-term functional outcome.  相似文献   
79.
BACKGROUND: Severe injury is associated with changes in monocytes that may contribute to poor outcomes. Longitudinal characterization of monocyte response patterns after trauma may provide added insight into these immunological alterations. METHODS: Venous blood obtained seven times during post-injury days 1 through 13 from 61 patients with an injury severity score >20 was assessed by flow cytometry for monocytes (CD14+) expressing HLA-DR or CD71 (transferrin receptor) and for circulating levels of interleukin (IL) 1alpha, IL-1beta, IL-6, soluble CD14 (sCD14), tumor necrosis factor-alpha (TNF-alpha), prostaglandin E(2) (PGE(2)), thromboxane B(2) (TXB(2)), and endotoxin. Urine neopterin was measured by high-pressure liquid chromatography, expressed as a neopterin-creatinine ratio. RESULTS: Trauma patients had leucocytosis days 1 through 13, monocytosis days 5 through 13, reduced proportions of CD14+HLA-DR+ cells days 2 through 5, and elevated proportions of CD14+CD71+ cells days 1 through 13. Neopterin was elevated all days, peaking on day 10. sCD14 was elevated days 2 through 13, and there were sporadic elevations of IL-1alpha, IL-1beta, IL-6, TNF-alpha, PGE(2), TXB(2), and endotoxin. Sepsis syndrome patients (n = 6) had larger and more prolonged reductions in CD14+HLA-DR+ cells and higher neopterin values, in comparison with uneventful patient outcomes. CONCLUSIONS: Altered proportions of monocytes expressing HLA-DR and CD71 and elevated sCD14 and urine neopterin levels, for up to 2 weeks after severe injury, underscores an extended period of profound immunological effects. Additional studies to more fully assess temporal monocyte response patterns after severe injury, including activation, may be warranted.  相似文献   
80.
Preoperative airway evaluation is essential to consider which is the best method of maintaining and protecting the airway during surgery and whether problems with airway management are likely. In general surgical patients, the prevalence of difficult intubation is low and tests have poor predictive power. This means that the patient may be evaluated as normal but prove to be difficult. The absence of reliable prediction in general surgical patients means that airway strategy holds the key to successful management. Where there are obvious abnormalities in the history, examination or imaging the preoperative evaluation will allow choice of the most appropriate airway strategy which may include preparation of the patient, assembling of alternative airway equipment, advice and help from a more senior or skilled anaesthetist or aid from a surgical colleague or assistant.  相似文献   
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