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The aim of this study was to assess the volumetric density (Vv) of the fibronectin in the periurethral region of patients with benign prostatic hyperplasia (BPH) and compare with a control group. Prostatic periurethral tissue samples were obtained from ten patients (age range 65 to 79 years, mean 66) with clinical symptoms of bladder outlet obstruction who had undergone open prostatectomy. The control group samples (periurethral tissue samples from the transitional zone) were collected from prostates obtained during autopsy of accidental death adults of less than 25 years. The volumetric density (Vv) of the fibronectin was determined with stereological methods from 25 random fields per sample using the point-count method with an M-42 grid test system. The quantitative data were analyzed using the Kolmogorov-Smirnov and Mann-Whitney U tests. The Vv in the control and BPH groups was 21.9% ± 1.5% and 29.1 % ± 1.2% in the fibronectin, respectively. BPH tissues presented a significant increase of fibronectin in prostatic periurethral region in the transitional zone that may cause lengthening of the prostatic urethra.  相似文献   
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Bone strength, a key determinant of fracture risk, has been shown to display clear sexual dimorphism after puberty. We sought to determine whether sex differences in bone mass and hip bone geometry as an index of strength exist in school‐age prepubertal children and the degree to which the differences are independent of body size and lean mass. We studied 3514 children whose whole‐body and hip scans were measured using the same densitometer (GE‐Lunar iDXA) at a mean age of 6.2 years. Hip dual‐energy X‐ray absorptiometry (DXA) scans underwent hip structural analyses (HSA) with derivation of bone strength indices. Sex differences in these parameters were assessed by regression models adjusted for age, height, ethnicity, weight, and lean mass fraction (LMF). Whole‐body bone mineral density (BMD) and bone mineral content (BMC) levels were 1.3% and 4.3% higher in girls after adjustment by LMF. Independent of LMF, boys had 1.5% shorter femurs, 1.9% and 2.2% narrower shaft and femoral neck with 1.6% to 3.4% thicker cortices than girls. Consequent with this geometry configuration, girls observed 6.6% higher stresses in the medial femoral neck than boys. When considering LMF, the sexual differences on the derived bone strength indices were attenuated, suggesting that differences in muscle loads may reflect an innate disadvantage in bone strength in girls, as consequence of their lower muscular acquisition. In summary, we show that bone sexual dimorphism is already present at 6 years of age, with boys having stronger bones than girls, the relation of which is influenced by body composition and likely attributable to differential adaptation to mechanical loading. Our results support the view that early life interventions (ie, increased physical activity) targeted during the pre‐ and peripubertal stages may be of high importance, particularly in girls, because before puberty onset, muscle mass is strongly associated with bone density and geometry in children. © 2015 American Society for Bone and Mineral Research.  相似文献   
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Methods to reliably measure tissue oxygenation in situ are currently lacking. We have developed a vertically oriented, dorsal, bipedicle flap model that is easy to perform, reliably reproduces tissue ischemia, eliminates craniocaudal variation, and is amenable to studying therapeutic modalities. The effect of narrowing this flap on tissue oxygenation measured with Licox electrodes has previously been presented. In this study we utilize in situ EPR spectroscopy to demonstrate the oxygen gradient in the flap as a function of flap width and placement of a silicone sheet directly under the flap. The effect of wound healing over a 2 week period is demonstrated. Twenty four, 300 gm male Sprague‐Dawley rats underwent creation of the bipedicle flap according to the following groups: 2.5 cm flap with silicone, 2.0 cm flap without silicone, 2.0 cm flap with silicone. Each group of 6 animals was injected with EMS char at 2 cm intervals along the flap and one injection in the control, non‐ischemic tissue. A 4th group underwent 2.0 cm flaps with silicone and use of lithium phthalocyanin as the paramagnetic material. Wound measurements and EPR spectroscopy were performed on days 3, 7, 10 and 14. On day 14, after EPR measurements, the animals were sacrificed and their wounds excised. One flap and one control wound were preserved for histologic analysis, the other flap and control wounds were prepared for lactate measurements. EPR spectroscopy demonstrated a gradient of oxygen that was lowest in the center of the flap and greatest at either end. Changes in the oxygen gradient correlated with narrowing and placement of the intervening silicone sheet. This new technology has never been utilized in an animal model of impaired wound healing. Comparison of recently developed paramagnetic materials for optimal tissue oxygen and free radical measurements will be presented.  相似文献   
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高效液相色谱法测定消痰咳片的含量   总被引:2,自引:0,他引:2  
目的:采用反相色谱法同时测定消痰咳片中两种主要成分甲氧苄啶和磺胺体的含量。方法:以乙腈:0.1%H3PO4(15:85)为流动相,检测波长254nm,HPLC法测定含量。结果:试验表明,甲氧苄啶和磺胺林在0.8-8ug范围内呈良好的线性关系,回归方程分别为Y=-1127.1+110.2x(r=0.9994),Y=-1852.3 256.2x(r=0.9996),相对标准偏差分别为2.1%和0.8%。结论:该方法简便、准确、可靠。  相似文献   
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Markers of oxidative stress and antioxidant activity in plasma and erythrocytes were studied for 14 d after birth in infants with neonatal respiratory distress syndrome ( n = 9) and controls ( n = 36). In plasma, the total radical trapping antioxidant capacity and the chain-breaking antioxidants vitamin C, sulfhydryl groups and bilirubin were similar. The differences in uric acid levels were not consistent, but vitamin E levels and vitamin E/total-lipid ratio were lower in the neonatal respiratory distress group ( p < 0.01). In erythrocytes, the antioxidant enzymes glutathione peroxidase, glutathione reductase and superoxide dismutase did not differ postnatally. Indicators of oxidative damage in plasma (sulfhydryl/protein ratio and thiobarbituric acid reactive substances) showed the same postnatal course in both groups and were not influenced by oxygen therapy. In erythrocytes the reduced/oxidized glutathione ratio showed no consistent differences. In conclusion, this study, using erythrocytes and plasma, does not provide convincing evidence of oxidative damage and diminished antioxidant defenses in preterm infants with neonatal respiratory distress syndrome.  相似文献   
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