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11.
We reviewed the records of 1,156 patients treated for acute staphylococcal osteitis or septic arthritis over a 12-year period; 38 had been critically ill with evidence of multiple-organ involvement and 30 (79%) had features of the toxic shock syndrome. The mortality rate of these 38 patients was 13% and the long-term orthopaedic complication rate was 39%. The diagnosis and management of patients with osteitis or septic arthritis, disseminated staphylococcal disease, and the toxic shock syndrome is discussed.  相似文献   
12.
Effect of positioning on oxygenation in single-lung transplant recipients.   总被引:1,自引:0,他引:1  
BACKGROUND: Many benefits and adverse effects of positioning are related to changes in ventilation and perfusion. A number of unique factors related to the allograft make the effects of positioning difficult to determine in single-lung transplant recipients. OBJECTIVES: To determine the effect of 3 body positions (supine, lateral with allograft lung down, and lateral with native lung down) on oxygenation and blood flow in single-lung transplant recipients in the 24 hours immediately after surgery. METHODS: A quasi-experimental repeated-measures design with stratified assignment to 1 of 3 different sequencing patterns for turning group was used to study 15 transplant recipients, 9 with emphysema and 6 with fibrosis. Oxygenation, ventilation, and blood flow measures (heart rate, blood pressure) were assessed after each turn. The effect of ischemic reperfusion injury was also explored. RESULTS: The oxygenation, ventilation, and bloodflow variables did not differ significantly across group, diagnosis, or time. Oxygenation variables measured when the allograft lung was dependent did not differ significantly from such measurements obtained when the native lung was dependent. CONCLUSIONS: No single position maximizes oxygenation in the immediate postoperative period in single-lung transplant recipients. Although a single standard protocol for positioning cannot be supported, the study does support the idea that transplant recipients can be safely turned in the immediate postoperative period without compromising oxygenation or hemodynamic status.  相似文献   
13.
1. Experiments were conducted to test the hypothesis that the responses of joint capsule mechanoreceptors better encode tissue stress or tissue strain. The experimental model was a small ligament from the cat knee capsule, which was stretched uniaxially in vitro. Experiments were done with either force or displacement as the controlled variable, and with steps, sinusoids, or pseudorandom Gaussian noise (PGN) as the input function. 2. The strength of coupling between neural discharge and both strain and stress was quantified during step experiments using linear correlation coefficients. The correlation between the frequency of neural discharge and stress was 0.93 +/- 0.09 (SD). The correlation between frequency of neural discharge and strain was -0.91 +/- 0.06. The magnitudes of these correlation coefficients were not significantly different. 3. The strength of coupling between neural discharge and both strain and stress during sinusoidal and PGN experiments was quantified by the use of an information theoretic statistic, transinformation. Out of 282 sinusoidal runs, transinformation between neural discharge and stress was significantly greater than transinformation between strain and neural discharge 241 times. Transinformation between strain and neural discharge was significantly greater 15 times. 4. During PGN experiments, transinformation between stress and neural discharge was greater than transinformation between strain and neural discharge in all 19 experimental runs. 5. Conditional transinformation between strain and neural discharge, given stress, was calculated for all sinusoidal and pseudorandom experiments. This statistic was greater than zero in 268 out of 289 experimental runs, indicating that a component of strain independent of stress is being signaled in the neural discharge.  相似文献   
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Anaerobic power is characterized by a high degree of specificity regarding both the recruited muscles as well as the recruitment pattern. The popular Wingate Anaerobic Test (WAnT) is a cycling test that does not satisfy the need for a running-specific anaerobic test. We describe such a test, using a novel type of a commercially available treadmill (BRL 1800, Gymrol, France). The ergometer is equipped with a torque motor to neutralize the frictional resistance of the treadmill belt, and a hip-belt harness connected to a horizontal rod. Force applied to the harness is monitored by a strain gauge mounted on the rod, while vertical movement is monitored by a potentiometer at the posterior fixed end of the rod. These, in conjunction with the treadmill belt speed, enable the computation of horizontal and vertical power as well as the combined total output. Power is calculated both as 'peak' power (highest 2.5 s segment) and 'mean' power (20 s duration). Preliminary results of young athletes were generally consistent with the expected age-related changes in anaerobic power. Values obtained on the anaerobic treadmill were always higher than the corresponding WAnT values previously obtained in comparable age groups. The higher values were probably due to the larger muscle mass involved and the shorter peak and mean power durations (2.5 and 20 s versus 5 and 30 s in the WAnT, respectively). This test should enable not only running-specific anaerobic power monitoring but also the characterization of the relationship between the horizontal and vertical components of that power.  相似文献   
16.
Growth hormone (GH) secretion declines during normal aging, resulting in lower serum insulin-like growth factor (IGF)-I levels. It has been proposed that many of the catabolic changes seen in normal aging, including osteoporosis and muscle atrophy, are in part caused by the decreased action of the GH-IGF-I axis. In addition, patients with GH deficiency have increased overall cardiovascular mortality. Several investigators have initiated GH treatment for elderly patients with relative hyposomatotropinemia. Initial reports suggest that GH can increase muscle mass, improve exercise tolerance, increase REM sleep and cause an enhanced sense of well-being. The basis for neuropsychiatric changes during GH therapy may be due to a direct CNS action of GH itself, to the increased IGF-I secretion which GH elicits, or to enhanced functioning of peripheral organ systems. Long-term studies will determine whether GH or IGF-I can exert a neurotrophic action in the aging brain.  相似文献   
17.
The pudendal thigh is a sensate fasciocutaneous flap supplied by the posterior labial artery. We report on the results of pudendal thigh flaps used for vaginal reconstruction in eight patients at the time of pelvic exenteration (6) and radical vaginectomy (2). Patients were interviewed and results were assessed 5 to 19 months after surgery. The flaps were raised in the thigh creases just lateral to the hair bearing area of the labia majora and included skin, subcutaneous tissues, deep fascia of the thigh, and the epimysium of the adductor muscles. Flap sizes varied from 9 × 4 cm to 15 × 6 cm. Bilateral flaps were used in seven patients. The flaps were technically easy to perform. Partial (apical) flap necrosis occurred in four patients. One patient developed complete necrosis of bilateral flaps, followed by an enterovaginal fistula. One patient whose flaps did not necrose developed a rectovaginal fistula at the site of rectal reanastomosis. The functional results are disappointing. The only patient having successful vaginal intercourse had a unilateral flap reconstruction following lower vaginectomy in a nonirradiated pelvis. No patient with bilateral flaps or prior pelvic irradiation has had successful coitus. Other long-term sequelae include vulvar pain (2), chronic vaginal discharge (2), hair growth (4), and protrusion of the flaps (2). These vulvovaginal symptoms discourage patients and their partners from genital contact. Breaching the integrity of the vulva to construct a neovagina that is likely to be unsuitable for sexual intercourse may deprive women of their only potential for normal genital sexual responsiveness. Techniques of vaginoplasty require continued assessment.  相似文献   
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The syndrome of inappropriate secretion of arginine vasopressin (AVP) known as the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) is associated with a variety of malignant and nonmalignant diseases. Only 17 cases of SIADH have been reported in the literature in association with cancer isolated to the head and neck. A retrospective review of 1,436 patients with head and neck malignancy excluding skin cancer through The University of Iowa Tumor Registry revealed 60 patients with the diagnosis of either SIADH or hyposmolality. A chart review for each of these patients was then done to establish the diagnosis of SIADH through relevant laboratory values and by excluding other causes of hyposmolality and hyponatremia. In 43 of these patients (3%), SIADH was found to be associated only with the cancer of the head and neck. We conclude that the incidence of SIADH in patients with cancer of the head and neck is much higher than previously recognized. As elevated serum AVP levels may not be clinically apparent unless associated with excessive water ingestation, it is possible that an even higher percentage of patients may have increased serum AVP levels.  相似文献   
20.
Sixty-seven patients with advanced carcinoma of the lower female genital tract (cervix, vagina, and vulva) were treated with radiation and concomitant intravenous cisplatin and/or 5-fluorouracil. Fifty-seven patients (85%) responded completely clinically. Thirty-five (61%) complete responders recurred with a median time to recurrence of 6 months. Twenty-six of the thirty-five patients who recurred had some component of local failure. The 22 complete responders who have not recurred have been followed a median of 13 months. Acute toxicity was minimal, with only 6 patients requiring interruption of therapy. Nine (13%) patients developed severe late complications and eight required surgery. The actuarial 5-year survival is 22%. This treatment regimen is disappointing in terms of both survival and local control.  相似文献   
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