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BACKGROUND: Recent guidelines suggest supplementation with ergocalciferol (vitamin D(2)) in chronic kidney disease stages 3 and 4 patients with elevated parathyroid hormone (PTH) levels and 25-hydroxyvitamin D (25OHD) levels <75 nmol/l. These guidelines are also applied to renal transplant patients. However, the prevalence rates of 25OHD deficiency and its association with PTH levels in renal transplant populations have not been extensively examined. We aimed to document the prevalence rates of 25OHD deficiency [defined by serum levels <40 nmol/l (<16 ng/ml)] and insufficiency [<75 nmol/l (<30 ng/ml)] in a single renal transplant centre, and examine its relationship with PTH levels. METHODS: Serum 25OHD and PTH concentrations were measured in 419 transplant patients attending a single renal transplant clinic over a 4-month period. Demographic and biochemical data were also collected, including serum creatinine, calcium, phosphate and albumin. Simple and multiple linear regression analysis were performed. RESULTS: In 27.3% of the patients, 25OHD deficiency was present, and 75.5% had insufficiency. On univariate analysis, 25OHD, serum albumin and estimated glomerular filtration rate (eGFR) were significantly associated with PTH levels (P < 0.0001, P = 0.004 and P < 0.0001, respectively). Multiple linear regression demonstrated that only 25OHD, eGFR and serum phosphate were significantly predictive of PTH levels (R(2) = 0.19, P < 0.0001). In this model, a 75 nmol/l increase in 25OHD will only result in a maximal reduction in PTH of 2.0 pmol/l. CONCLUSIONS: We conclude that 25OHD deficiency and insufficiency are common in renal transplant patients and may exacerbate secondary hyperparathyroidism. However, 25OHD, eGFR and phosphate only account for 19% of the variability in PTH levels. In addition, even a large increase in serum 25OHD levels is likely to result in only a small reduction in PTH. Therefore, alternative approaches to managing hyperparathyroidism in renal transplant recipients rather than supplementation with ergocalciferol are warranted.  相似文献   
85.
Toby O. Smith   《Physiotherapy》2006,92(3):135-145
Pretibial lacerations and lower limb wounds are referred to plastic surgery teams for split skin graft surgery. Traditionally, these patients have been immobilised on bedrest following surgery. More recently, patients have commenced ambulation earlier to avoid medical complications and facilitate discharge. The objective of this literature review was to determine when such patients should begin walking. A literature search was undertaken using the electronic databases AMED, Cinahl, Embase, Medline (via Ovid), PEDro and Pubmed. Clinical trials using human subjects, written in English, were included. Seventeen (of 1137) papers met the inclusion criteria and were reviewed. The literature suggested that patients should begin walking immediately or at the earliest possible opportunity after lower limb skin graft surgery. Although the literature advocated early ambulation, the evidence base presented with a number of recurrent methodological limitations, including small sample sizes, lack of a control sample, and limited follow-up. Accordingly, further research employing large, well-designed, randomised controlled trials is recommended. It will then be possible to understand with greater certainty when patients should begin walking after lower extremity split skin graft surgery.  相似文献   
86.
OBJECTIVE: To establish reference intervals for the fetal right, left and total lung volumes and heart volume between 12 and 32 weeks of gestation. METHODS: Fetal lung and heart volumes were measured using three-dimensional (3D) ultrasound in 650 normal singleton pregnancies at 12-32 weeks. The VOCAL (Virtual Organ Computer-aided AnaLysis) technique was used to obtain a sequence of six sections of each lung and the heart around a fixed axis, each after a 30 degrees rotation from the previous one. The rotation axis for the lungs extended from the apex to the upper limit of the diaphragm dome, and the rotation axis for the heart extended from its apex to its connection to the great vessels. The contour of each of these organs was drawn manually in the six different rotation planes to obtain the 3D volume measurement. In 60 cases the fetal lungs and heart volumes were measured by the same sonographer twice and also by a second sonographer once in order to compare the measurements and calculate intra- and interobserver agreement. RESULTS: The total lung volume and heart volume increased with gestation, from respective mean values of 1.6 and 0.6 mL at 12 weeks to 10.9 and 4.3 mL at 20 weeks and 49.3 and 26.6 mL at 32 weeks. The right to left lung volume ratio did not change significantly with gestation (median, 0.7), whereas the heart to total lung volume ratio increased with gestation from about 0.3 at 12 weeks to 0.5 at 32 weeks. In the Bland-Altman plot, the difference between paired measurements by two sonographers was, in 95% of the cases, less than 0.05, 0.5 and 1.9 mL for each lung at 12-13, 19-22 and 29-32 weeks, respectively, and the corresponding values for the heart volumes were 0.04, 0.4 and 2.3 mL. CONCLUSIONS: In normal fetuses the lung and heart volumes increase between 12 and 32 weeks of gestation. The extent to which in pathological pregnancies possible deviations in these measurements from normal prove to be useful in the prediction of outcome remains to be determined.  相似文献   
87.
We report the case of a 38-year-old woman who presented with chronic lower abdominal pain. Her past medical history included a splenectomy due to abdominal trauma. Ultrasound examination revealed four pelvic tumors which, upon laparotomy, were found to be the result of splenosis. Approximately 100 cases of splenosis have been reported but only a minority of them have been published in the gynecological literature. Our case indicates that those involved in pelvic scanning (even of asymptomatic women) and/or treating those complaining of lower abdominal pain or presenting with pelvic tumors should be aware of splenosis as a possible diagnosis.  相似文献   
88.
We describe the simple adaptation of a standard fluorescent microscope for illumination using a 'Royal Blue' Luxeon light emitting diode (LED) and demonstrate that this form of illumination is suitable for the detection of auramine O stained Mycobacterium spp. The low cost, low power consumption, safety and reliability of LEDs makes them attractive alternatives to mercury vapour lamps.  相似文献   
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Aggressive behavior linked to corticotropin-reactive autoantibodies.   总被引:3,自引:0,他引:3  
BACKGROUND: Altered stress response is characteristic for subjects with abnormal aggressive and antisocial behavior, but the underlying biological mechanisms are unclear. We hypothesized that autoantibodies (autoAbs) directed against several stress-related neurohormones may exist in aggressive subjects. METHODS: Using enzyme-linked immunosorbent assay, we studied whether autoAbs directed against corticotropin (ACTH), alpha-melanocyte-stimulating hormone (alpha-MSH), oxytocin, and vasopressin are present in serum of male subjects with conduct disorder and prisoners with history of violence. Healthy blood donors served as control subjects. RESULTS: Both conduct disorder and prisoners groups displayed strongly increased levels of ACTH-reactive immunoglobulin G (IgG) and immunoglobulin M (IgM) autoAbs compared with control subjects. Levels of oxytocin-reactive IgM autoAbs were slightly increased in both groups of aggressive subjects, whereas levels of vasopressin-reactive IgG and IgM autoAbs were lower only in conduct disorder. No differences in the levels of alpha-MSH-reactive autoAbs were found between aggressive and control subjects. CONCLUSIONS: High levels of ACTH-reactive autoAbs as well as altered levels of oxytocin- and vasopressin-reactive autoAbs found in aggressive subjects may interfere with the neuroendocrine mechanisms of stress and motivated behavior. Our data suggest a new biological mechanism of human aggressive behavior that involves autoAbs directed against several stress-related neurohormones.  相似文献   
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