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141.
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OBJECTIVE: Weight assessment is a critical aid in patient care. It is particularly important in monitoring progression of pregnancies, heart failure status, and when adjusting medications. Although weight is generally determined using a scale, few studies have evaluated the precision of non-household scales. The objective of this study was to assess scale precision across a variety of settings. METHODS: An evaluation of scales from randomly selected primary care clinics (n=30), diabetology/endocrinology clinics (n=7), weight loss facilities (n=25), and fitness centers (n=30) was performed. Assessments were completed on a total of 223 scales: 94 from primary care clinics, 32 from diabetology/endocrinology clinics, 39 from weight loss centers, and 58 from fitness centers. Scales were assessed for condition, location in facility, resting surface, commercial designation, and calibration history. Scale precision was validated using 100 lb. (45.5 kg), 150 lb. (68.3 kg), 200 lb. (90.9 kg), and 250 lb. (113.6 kg) certified weights. RESULTS: Overall, scales demonstrated decreased precision with increased weight. At higher weights, more than 15% of scales were off by more than 6 lbs. (2.3 kg), approximately 1 Body Mass Index (BMI) unit. While facility type was not significant, condition, location in facility, resting surface, commercial designation, and calibration history were significant. CONCLUSIONS: This study demonstrates that many scales used to measure body weight are imprecise and that scales in health care settings are no more precise than those in other facilities. Clinical decisions based on scales that are imprecise have the potential to cause iatrogenic complications in patient care.  相似文献   
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We describe two patients with a diffuse haemangioma of the lower limb complicated by pathological fracture of the femoral shaft, one of whom was treated by a bone graft and immobilisation in a cast, and the other by external fixation and injection of bone marrow. A review of the literature identified difficulty in control of bleeding and obtaining bony union.  相似文献   
144.
BACKGROUND: Subdiaphragmatic activity and diaphragmatic motion both contribute to inferior wall artifacts in technetium 99m myocardial perfusion single photon emission computed tomography (SPECT). METHODS AND RESULTS: We used an anthropomorphic phantom with ventricular wall activity, liver/spleen inserts containing variable Tc-99m activity, and variable vertical (diaphragmatic) motion amplitude. SPECT and transmission scans were obtained on a GE Optima NX camera. Data were processed by use of filtered backprojection or attenuation correction (AC). Resulting myocardial activity maps were analyzed with standardized inferior-anterior and anterior-lateral wall ratios. At a subdiaphragmatic-myocardial activity ratio of 0.5:1, inferior wall attenuation predominates, producing a cold artifact. AC corrects inferior wall activity to the level of the anterior wall irrespective of diaphragmatic motion. At a subdiaphragmatic-myocardial activity ratio of 1:1, inferior wall counts vary widely depending on the proximity of subdiaphragmatic activity to the ventricle. With increasing diaphragmatic amplitude, the overlap of subdiaphragmatic activity and inferior wall worsens, leading to a complex mixture of cold and hot artifacts, not corrected by AC. CONCLUSIONS: Concentration and proximity of subdiaphragmatic Tc-99m activity relative to myocardium comprise a major factor in the nature and severity of inferior wall artifacts. If the subdiaphragmatic Tc-99m concentration is equivalent to that in the myocardium, complex, potentially uninterpretable hot and cold inferior wall artifacts are produced.  相似文献   
145.
The development of an optimal islet cryopreservation method will permit transplantation of islets from multiple donors in a single procedure and contribute to alleviation of the islet shortage. In this study, we have improved human islet cryopreservation methods under serum-free conditions using an intracellular-based islet cryopreservation solution (ICS), especially supplemented with a p38 pathway inhibitor (p38IH) to suppress p38 mitogen-activated protein kinase (MAPK) activation. Three different solutions were compared for freezing and thawing of human islets (1) conventional RPMI1640 medium, (2) ICS, and (3) ICS supplemented with a p38IH, SD-282 (ICS-p38IH). Islet cryopreservation with ICS-p38IH significantly improved islet recovery, viability, and quality after thawing of cryopreserved islets. This improvement may allow the use of cryopreserved islets in clinical islet transplantation.  相似文献   
146.
BACKGROUND: Secondary hyperparathyroidism is a common complication among long-term dialysis patients. The method of predicting future parathyroid function has not yet been established. Fibroblast growth factor-23 (FGF-23) is a newly found humoral phosphaturic factor. METHODS: One hundred and three nondiabetic dialysis patients whose plasma intact parathyroid hormone (PTH) levels were below 300 pg/mL were included in the study. Blood samples were stored at -80 degrees C for 2 years. Meanwhile, each physician in charge decided upon the strategy of medical therapy for maintaining intact PTH levels between 150 and 300 pg/mL. Patients were judged 2 years after the sample collection with regard to whether the hyperparathyroidism responded to the medical therapy. The definition of refractory secondary hyperparathyroidism was either (1) retaining intact PTH levels greater than 300 pg/mL 2 years after sample collection, or (2) having received the parathyroid intervention therapy during the observation period. Serum FGF-23 levels were determined with a sandwich enzyme-linked immunosorbent assay system that detects biologically active human FGF-23. RESULTS: Seventeen patients with intact PTH levels greater than 300 pg/mL were judged as having secondary hyperparathyroidism refractory to medical therapy. A stepwise regression analysis revealed that only serum levels of FGF-23 were significantly related to the prognosis of parathyroid function. A receiver-operated characteristic analysis demonstrated that the area under the curves obtained from FGF-23 (7099.9) was significantly greater than that obtained from intact PTH (6306.4, P < .01) and Ca x Pi (5670.3, P <.0001). Although the plasma intact PTH levels at the beginning of the observation period were comparable to each other, the intact PTH levels at 2 years after the sample collection were significantly higher in the patients with FGF-23 >/=7500 ng/L than in those with FGF-23 <7500 ng/L (P < .0001). CONCLUSION: Serum FGF-23 level was found to be the most useful factor in predicting future development of refractory secondary hyperparathyroidism in long-term dialysis patients with mild secondary hyperparathyroidism. The measurement of serum FGF-23 levels is a promising laboratory examination that can be applied in the clinical practice of uremic secondary hyperparathyroidism.  相似文献   
147.
The goal of this study was to investigate fetal exposure to phytoestrogens, estrogenic compounds derived from plants, by measuring serum concentrations of phytoestrogens in maternal and cord blood. This study included 51 mothers scheduled for cesarean section (C-section), to obtain the serum of mother and fetus at almost the same time. Serum concentrations of phytoestrogens, including genistein (Gen), daidzein (Dai), coumestrol (Cou), equol (Equ; a metabolite of Dai), and sulfate-conjugated Gen, were measured in maternal and cord blood samples by LC-MS/MS and HPLC. It was found that phytoestrogens were transferred from mother to fetus. The detection rates of Gen, Dai, Equ, and Cou in cord serum were 100%, 80%, 35%, and 0%, respectively. Levels of Gen and Dai were higher in cord than in maternal serum (mean=19.4 ng/ml vs.7.2 ng/ml and 4.3 ng/ml vs.1.8 ng/ml for Gen and Dai, respectively). However, a reverse pattern was seen for Equ (cord mean=0.9 ng/ml, maternal mean=2.0 ng/ml). The correlations were significant between the concentration levels of Gen and Dai, Gen and Equ, and Gen and Dai plus Equ in cord serum. However, in maternal serum, the correlations were weak. Also, in 8 of 10 cord serum samples, sulfate-conjugated Gen was detected (mean=5.2 ng/ml, standard deviation=4.7), but it was detected from only one maternal serum (8.7 ng/ml). This study demonstrates placental transfer of phytoestrogens from mother to fetus. It is suggested that the metabolic and/or excretion rates of phytoestrogens are different between mother and fetus and once phytoestrogens are transferred to the fetus, they tend to stay in the fetal side longer than in the maternal side. While the implications for the health and development of the newborn are not known, these data suggest that the effects of fetal exposure to phytoestrogens should be studied further.  相似文献   
148.
Sagittal laxity in vivo after total knee arthroplasty   总被引:1,自引:0,他引:1  
Introduction A stress arthrometry study of 77 knees undergoing total knee arthroplasty was performed to determine the difference in anteroposterior (AP) laxity between posterior cruciate ligament (PCL)-retaining (PCLR) and PCL-substituting (PCLS) prostheses using the Genesis I TKA.Materials and methods Fifty-three knees had PCLR and 24 had PCLS prostheses. The selected patients had successful arthroplasties after a minimum follow-up of 5 years. AP laxity was measured with a KT-2000 arthrometer (Medmetric, San Diego, CA, USA) using standard protocols.Results At 30° of flexion, there was no statistical difference in anterior (PCLR: 4.7 mm, PCLS: 4.5 mm), posterior (PCLR: 1.1 mm, PCLS: 0.7 mm), or total (PCLR: 5.8 mm, PCLS: 5.3 mm) displacement. At 75°, significant differences were seen in both anterior (PCLR: 3.3 mm, PCLS: 2.3 mm) and total (PCLR: 4.8 mm, PCLS: 3.4 mm) displacement (p=0.001 and p=0.009, respectively), although there was no statistical difference in posterior displacement (PCLR: 1.5 mm, PCLS: 1.1 mm).Conclusion The above values are considered the suitable degree of AP laxity in total knee arthroplasty for a satisfactory clinical outcome 5–9 years after surgery. The PCL in a PCLR prosthesis and the central tibial spine and femoral cam in a PCLS prosthesis might play comparable roles in determining the laxity in the posterior direction in these prostheses.  相似文献   
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