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991.
Bone Mass and Strength in School‐Age Children Exhibit Sexual Dimorphism Related to Differences in Lean Mass: The Generation R Study
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Carolina Medina‐Gomez Denise HM Heppe Jia‐Lian Yin Katerina Trajanoska André G Uitterlinden Thomas J Beck Vincent WV Jaddoe Fernando Rivadeneira 《Journal of bone and mineral research》2016,31(5):1099-1106
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
992.
Hongxia Zhai Liang Li Yaxin Yin Jinjin Zhang Haiwei Chen Runmei Liu 《Renal failure》2016,38(3):437-441
The aim of this study was to explore the efficacy and safety of hemodialysis in interventional therapy for patients with coronary artery disease combined with chronic renal insufficiency. With the aging and social development, the number of coronary artery disease patients with chronic renal insufficiency gradually increased. Total 58 coronary heart disease patients with chronic renal dysfunction were selected. These patients were characterized with typical angina symptoms and typical electrocardiogram (ECG) changes of onset angina. Continuous oral administration of sodium bicarbonate tablets 1?g 3/day?×?3 days and slow intravenous input sodium chloride 1000 ~1500 mL 3–12?h before operation were given. By this way, all patients were treated by hydration and alkalization. After percutaneous coronary intervention (PCI) treatment, patients were immediately transferred to undergo 4?h of dialysis treatment without removing indwelling of femoral artery puncture sheath tube to protect renal function. Changes in renal function including serum creatinine, glomerular filtration rate, and urine were observed and recorded. All patients were successfully underwent PCI treatment. Within one month after PCI, there were no obvious complication and no stent thrombosis occurred. Among of 58 patients, 56 cases showed no significant increase in serum creatinine levels compared with those before operation. However, serum creatinine level of one patient increased to 251?umol/L and one patient still required permanent dialysis. Using hemodialysis in interventional therapy in coronary artery disease patients with chronic renal insufficiency could significantly improve the prognosis of the patients. 相似文献
993.
994.
Mun Keong Kwan Chee Kidd Chiu Chris Yin Wei Chan Reza Zamani Nils Hansen-Algenstaedt 《European spine journal》2016,25(6):1745-1753
Purpose
To directly compare the safety of fluoroscopic guided percutaneous thoracic pedicle screw placement between Caucasians and Asians.Methods
This was a retrospective computerized tomography (CT) evaluation study of 880 fluoroscopic guided percutaneous pedicle screws. 440 screws were inserted in 73 European patients and 440 screws were inserted in 75 Asian patients. Screw perforations were classified into Grade 0: no violation; Grade 1: <2 mm perforation; Grade 2: 2–4 mm perforation; and Grade 3: >4 mm perforation. For anterior perforations, the pedicle perforations were classified into Grade 0: no violation, Grade 1: <4 mm perforation; Grade 2: 4–6 mm perforation; and Grade 3: >6 mm perforation.Results
The inter-rater reliability was adequate with a kappa value of 0.83. The mean age of the study group was 58.3 ± 15.6 years. The indications for surgery were tumor (70.3 %), infection (18.2 %), trauma (6.8 %), osteoporotic fracture (2.7 %) and degenerative diseases (2.0 %). The overall screw perforation rate was 9.7 %, in Europeans 9.1 % and in Asians 10.2 % (p > 0.05). Grade 1 perforation rate was 8.4 %, Grade 2 was 1.2 % and Grade 3 was 0.1 % with no difference in the grade of perforations between Europeans and Asians (p > 0.05). The perforation rate was the highest in T1 (33.3 %), followed by T6 (14.5 %) and T4 (14.0 %). Majority of perforations occurred medially (43.5 %), followed by laterally (25.9 %), and anteriorly (23.5 %). There was no statistical significant difference (p > 0.05) in the perforation rates between right-sided pedicle screws and left-sided pedicle screws (R: 10.0 %, L: 9.3 %).Conclusions
There were no statistical significant differences in the overall perforation rates, grades of perforations, direction of perforations for implantation of percutaneous thoracic pedicle screws insertion using fluoroscopic guidance between Europeans and Asians. The safety profile for this technique was comparable to the current reported perforation rates for conventional open pedicle screw technique.995.
Mun Keong Kwan Kai Ann Wong Chee Kean Lee Chris Yin Wei Chan 《European spine journal》2016,25(2):401-408
Purpose
To introduce a new clinical neck tilt grading and to investigate clinically and radiologically whether neck tilt and shoulder imbalance is the same phenomenon in AIS patients.Methods
89 AIS Lenke 1 and 2 cases were assessed prospectively using the new clinical neck tilt grading. Shoulder imbalance and neck tilt were correlated with coracoid height difference (CHD), clavicle\rib intersection distance (CRID), clavicle angle (CA), radiographic shoulder height (RSH), T1 tilt and cervical axis.Results
Mean age was 17.2 ± 3.8 years old. 66.3 % were Lenke type 1 and 33.7 % were type 2 curves. Strong intraobserver (0.79) and interobserver (0.75) agreement of the clinical neck tilt grading was noted. No significant correlation was observed between clinical neck tilt and shoulder imbalance (0.936). 56.3 % of grade 3 neck tilt, 50.0 % grade 2 neck tilt patients had grade 0 shoulder imbalance. In patients with grade 2 shoulder imbalance, 42.9 % had grade 0, 35.7 % grade 1, 14.3 % grade 2 and only 7.1 % had grade 3 neck tilt. CHD, CRID, CA and RSH correlated with shoulder imbalance. T1 tilt and cervical axis measurements correlated with neck tilt.Conclusions
In conclusion, neck tilt is distinct from shoulder imbalance. Clinical neck tilt has poor correlation with clinical shoulder imbalance. Clinical neck tilt grading correlated with cervical axis and T1 tilt whereas clinical shoulder grading correlated with CHD, RSH CRID and CA.996.
Xin Hua Yin Shao Hua Liu Jin Song Li Yong Chen Xiong Ke Hu Ke Feng Zeng Hong Gui Yu Zhen Hai Zhou Hong Qi Zhang 《European spine journal》2016,25(4):1047-1055
Purpose
We present a retrospective study of patients with multilevel contiguous tuberculous spondylitis of thoracic region that underwent single-stage posterolateral debridement and fusion and following posterior instrumentation.Methods
From June 2000 to March 2009, 870 consecutive spinal tubercular patients including 36 patients who were diagnosed and treated as multilevel contiguous thoracic spinal tuberculosis in our institution. Apart from five patients being treated conservatively, the 31 cases received surgery by single-stage posterolateral debridement, fusion, following posterior instrumentation and postural drainage. The patients were evaluated based on the Frankel scoring system, kyphotic Cobb angle, and visual analog scale (VAS) pain score.Results
The mean duration of postoperative follow-up was 79.2 ± 9.9 months (range 62–98 months). Neither mortalities nor any major complications were found. Solid bony fusion was achieved in all patients. No patients with neurological deficit deteriorated postoperatively. According to Frankel scoring system, 7 cases were rated as Grade D, 24 cases as Grade E at last follow-up. The average preoperative Cobb’s angle was 32° (range 21°–39°). The average early postoperative Cobb’s angle was 23° (range 15°–32°). The mean latest postoperative Cobb’s angle was 26° (range 20°–32°), with a small loss of correction at last follow-up. Pre-op VAS was 8.8 ± 0.7 (range 7–10) and final follow-up was 1.8 ± 1.1. There was a significant difference of VAS between preoperation and the final follow-up.Conclusions
One-stage surgical treatment for multilevel contiguous spinal tuberculosis by posterolateral debridement, fusion, posterior instrumentation can be an effective and feasible treatment method.997.
998.
Keguang Chen Dongming Yin Huiying Lyu Lin Yang Tianyu Zhang 《Acta oto-laryngologica》2016,136(5):470-474
Conclusions With the aggravation of the external auditory canal malformation, the size of extra-niche fossa became smaller, providing concrete data and valuable information for the better design, selecting and safer implantation of the transducer in the area of round window niche. Three-dimensional measurements and assessments before surgery might be helpful for a safer surgical approach and implantation of a vibrant soundbridge.Objectives The aim of this study was to investigate whether differences exist in the morphology of the posterior tympanum related to the round window vibroplasty among congenital aural atresia (CAA), congenital aural stenosis (CAS), and a normal control group, and to analyze its effect on the round window implantation of vibrant soundbridge.Methods CT images of 10 normal subjects (20 ears), 27 CAS patients (30 ears), and 25 CAA patients (30 ears) were analyzed. The depth and the size of outside fossa of round window niche related to the round window vibroplasty (extra-niche fossa)and the distances between the center of round window niche and extra-niche fossa were calculated based on three-dimensional reconstruction using mimics software. Finally, the data were analyzed statistically.Results The size of extra-niche fossa in the atresia group was smaller than in the stenosis group (p?0.05); furthermore, the size of extra-niche fossa in the stenosis group was smaller than that of the control group (p?0.05). There was no statistically significant difference of the depth of extra-niche fossa among different groups. 相似文献
999.
Conclusions: Vestibular function disorders were widespread among nasopharyngeal carcinoma (NPC) patients. The radiation doses to the inner ears were associated with the incidence of vestibular function disorders, but the correlations were mild. The inflammatory responses and possible resolution obstacles of inflammation participated in persistent vestibular function disorders after irradiation. Objectives: To investigate the incidence of vestibular function disorders in NPC patients after irradiation and potential mechanisms. Methods: Patients who received radical intensity-modulated radiotherapy for their NPC were recruited. The serum levels of IL-6 and IL-17 were detected by ELISA method. Vestibular evoked myogenic potential (VEMP) tests were used to evaluate vestibular function and correlation analyses were used to analyze the potential mechanisms of vestibular function disorders. Results: Thirty-eight patients were included. The incidences of abnormal ocular VEMP (oVEMP) and cervical VEMP (cVEMP) were 65.79% and 80.26% at the time of completion of radiotherapy, and 61.84% and 71.05% at 3 months after radiotherapy. The mean and maximum radiation doses to the inner ears were both significantly associated with abnormal oVEMP and cVEMP (p?0.05, all), but the correlations were all mild. The serum levels of IL-6 and IL-17 were both significantly associated with abnormal oVEMP and cVEMP after irradiation (p?0.05, all). 相似文献
1000.
目的检测绵阳地区不同民族的中老年人骨密度(bone mineral density,BMD)情况,了解BMD是否与民族因素有关。方法用双能X线骨密度检测仪检测绵阳市城区、郊区和农村5039例50岁以上自愿者(其中男性1895例,女性3144例)腰椎(L1-4)和左侧股骨颈和Ward’s三角BMD,对不同民族人的BMD进行比较。结果本次检测人群包括汉族、藏族、羌族、回族,各年龄组男性和女性,各民族BMD分别比较,男性和女性比较的结果均显示,汉族BMD显著高于藏族、羌族、回族,回族高于羌族和藏族,羌族高于藏族(P0.05)。结论 BMD与民族有关,产生民族差异可能与遗传、生活地区、饮食结构有关。造成BMD民族差异的这些因素还需进一步证实。 相似文献