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21.
Nitric oxide (NO) is an important inhibitoryneurotransmitter in the gut. Alterations in NO mediatedresponses have been described in diabetic animals. Thepresence of nitric oxide synthase (NOS) reflects the potential for NO synthesis and is found inneurons in the myenteric plexus. The aim of this studywas to determine changes in nitric oxide synthase (NOS)expression in the myenteric plexus of thegastrointestinal tract of diabetic rats at three months ofstreptozotocin-induced diabetes, compared to age matchedcontrols, using immunohistochemistry. Diabetic animalsshowed a decrease in NOS expression in the antrum, with 59.1 ± 7.3% of neurons beingpositive for NOS in diabetes compared to 81.2 ±4.7% in controls (P < 0.05). NOS expression induodenum, ileum, and colon of diabetic animals was notstatistically different from controls. Decreased expression of NOS inantrum may contribute to altered gastric emptyingobserved in diabetics.  相似文献   
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Sclerostin antibody (Scl‐Ab) increases osteoblast activity, in part through increasing modeling‐based bone formation on previously quiescent surfaces. Histomorphometric studies have suggested that this might occur through conversion of bone lining cells into active osteoblasts. However, direct data demonstrating Scl‐Ab‐induced conversion of lining cells into active osteoblasts are lacking. Here, we used in vivo lineage tracing to determine if Scl‐Ab promotes the conversion of lining cells into osteoblasts on periosteal and endocortical bone surfaces in mice. Two independent, tamoxifen‐inducible lineage‐tracing strategies were used to label mature osteoblasts and their progeny using the DMP1 and osteocalcin promoters. After a prolonged “chase” period, the majority of labeled cells on bone surfaces assumed a thin, quiescent morphology. Then, mice were treated with either vehicle or Scl‐Ab (25 mg/kg) twice over the course of the subsequent week. After euthanization, marked cells were enumerated, their thickness quantified, and proliferation and apoptosis examined. Scl‐Ab led to a significant increase in the average thickness of labeled cells on periosteal and endocortical bone surfaces, consistent with osteoblast activation. Scl‐Ab did not induce proliferation of labeled cells, and Scl‐Ab did not regulate apoptosis of labeled cells. Therefore, direct reactivation of quiescent bone lining cells contributes to the acute increase in osteoblast numbers after Scl‐Ab treatment in mice. © 2016 American Society for Bone and Mineral Research.  相似文献   
23.
Higher rates of hip fracture and all fractures combined have been observed in urban compared with rural areas, but whether there are urban‐rural differences in distal forearm fracture rates is less studied. The aim of this longitudinal study was to compare the incidence of forearm fracture in postmenopausal women in urban and rural areas in Norway and to investigate risk factors that could explain potential fracture differences. The study included data from 11,209 women aged 65 years or more who participated in two large health studies, the Tromsø Health Study in 1994–1995 and the Nord‐Trøndelag Health Study in 1995–1997. Forearm bone mineral density (BMD) was measured by single‐energy X‐ray absorptiometry in a subsample of women (n = 7333) at baseline. All women were followed with respect to hospital‐verified forearm fractures (median follow‐up 6.3 years). A total of 9249 and 1960 women lived in areas classified as rural and urban, respectively. Urban women had an increased forearm fracture risk [relative risk (RR) = 1.29, 95% confidence interval (CI) 1.09–1.52] compared with women in rural areas. Rural women had higher body mass index (BMI) than urban women, and the RR was moderately reduced to 1.21 (95% CI 1.02–1.43) after BMI adjustments. Rural women had the highest BMD. In the subgroup with measured BMD, adjustments for BMD changed the urban versus rural RR from 1.21 (95% CI 0.96–1.52) to 1.05 (95% CI 0.83–1.32), suggesting that BMD is an important explanatory factor. In conclusion, higher rates of forearm fractures was found in urban compared with rural women. © 2011 American Society for Bone and Mineral Research.  相似文献   
24.
Older adults with type 2 diabetes (T2D) tend to have normal or greater areal bone mineral density (aBMD), as measured by DXA, than those who do not have diabetes (non‐T2D). Yet risk of fracture is higher in T2D, including 40% to 50% increased hip fracture risk. We used HR‐pQCT to investigate structural mechanisms underlying skeletal fragility in T2D. We compared cortical and trabecular bone microarchitecture, density, bone area, and strength in T2D and non‐T2D. In secondary analyses we evaluated whether associations between T2D and bone measures differed according to prior fracture, sex, and obesity. Participants included 1069 members of the Framingham Study, who attended examinations in 2005 to 2008 and underwent HR‐pQCT scanning in 2012 to 2015. Mean age was 64 ± 8 years (range, 40 to 87 years), and 12% (n = 129) had T2D. After adjustment for age, sex, weight, and height, T2D had lower cortical volumetric BMD (vBMD) (p < 0.01), higher cortical porosity (p = 0.02), and smaller cross‐sectional area (p = 0.04) at the tibia, but not radius. Trabecular indices were similar or more favorable in T2D than non‐T2D. Associations between T2D and bone measures did not differ according to sex or obesity status (all interaction p > 0.05); however, associations did differ in those with a prior fracture and those with no history of fracture. Specifically, cortical vBMD at the tibia and cortical thickness at the radius were lower in T2D than non‐T2D, but only among those individuals with a prior fracture. Cortical porosity at the radius was higher in T2D than non‐T2D, but only among those who did not have a prior fracture. Findings from this large, community‐based study of older adults suggest that modest deterioration in cortical bone and reductions in bone area may characterize diabetic bone disease in older adults. Evaluation of these deficits as predictors of fracture in T2D is needed to develop prevention strategies in this rapidly increasing population of older adults. © 2017 American Society for Bone and Mineral Research.  相似文献   
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老年性肺部真菌感染60例临床分析   总被引:1,自引:0,他引:1  
【目的】探讨老年人肺部真菌感染的相关因素。【方法】对我们收治的60例老年性肺部真菌感染患者的资料进行回顾分析,寻找其感染菌群的病原体及可能与真菌感染相关的因素。【结果】老年性肺部真菌感染主要菌群为白色念珠茵,其发生可能与下列因素密切相关:基础疾病、抗生素的应用、低蛋白血症、糖皮质激素的应用。【结论】老年性肺部真菌感染主要茵群为白色念珠菌,基础疾病、抗生素的应用、低蛋白血症、糖皮质激素的应用可能是肺部真菌感染的相关危险因素,而中医药在治疗该病方面有独特的优势:  相似文献   
28.
Greater bone marrow adiposity (BMAT) is associated with lower bone mineral density (BMD) and vertebral fractures; less is known about BMAT composition and bone. We studied BMAT composition and bone outcomes in 465 participants from the Age Gene/Environment Susceptibility (AGES)-Reykjavik study. BMAT saturation and unsaturation, measured with magnetic resonance spectroscopy, were defined as the ratio of saturated (1.3 ppm peak) or unsaturated (5.3 ppm peak) lipid to total marrow contents, respectively. At baseline and follow-up visits, spine and hip BMD were assessed with quantitative computed tomography (QCT) and dual-energy X-ray absorptiometry (DXA) and vertebral fractures were identified with DXA. Incident clinical fractures were identified through medical records for up to 8.8 years of follow-up. Associations between BMAT composition and BMD, bone loss, and fractures were evaluated in adjusted regression models. At baseline, mean ± standard deviation (SD) participant age was 81.7 ± 4.3 years, mean BMAT unsaturation was 3.5% ± 1.0%, and mean saturation was 46.3% ± 7.2% in the full cohort (47.7% women). Each SD increase in BMAT saturation was associated with lower trabecular BMD: −23.6% (spine) and −13.0% (total hip) (all p < 0.0001). Conversely, BMAT unsaturation (per SD increase) was associated with higher trabecular BMD: +17.5% (spine) and +11.5% (total hip) (all p < 0.001). BMAT saturation (per SD increase) was associated with greater risk for prevalent (odds ratio [OR] 1.46; 95% confidence interval [CI], 1.11–1.92) and incident (OR 1.55; 95% CI, 1.03–2.34) vertebral fracture. BMAT unsaturation (per SD increase) was associated with lower risk for incident vertebral fracture (OR 0.58; 95% CI, 0.38–0.89). In gender stratified analyses, BMAT saturation and unsaturation had opposite associations with incident clinical fracture among men. In general, saturated marrow lipids were associated with worse skeletal outcomes, whereas unsaturated lipids were associated with better outcomes. We recommend that future studies of marrow fat and skeletal health report measurements of saturated and unsaturated marrow lipids, rather than total marrow fat content alone. © 2022 American Society for Bone and Mineral Research (ASBMR).  相似文献   
29.
肾动脉平面以上主动脉瘤的治疗   总被引:8,自引:0,他引:8  
目的 探讨肾动脉平面以上主动脉瘤 (AAARA)的治疗经验。方法 回顾性分析12 0例AAARA的临床资料。结果 夹层动脉瘤 84例 ,真性动脉瘤 2 7例 ,假性动脉瘤 9例。病变累及全程主动脉者 12例 ,主动脉弓 9例 ,胸降主动脉 2 0例 ,降胸至腹主动脉分叉部或以下 43例 ,胸腹主动脉 2 5例 ,涉及内脏动脉 11例。施行手术或支架型人工血管微创治疗74例。术中至术后 30d内死亡 11例 (14 9% )。术后并发症 9例 ,无截瘫、偏瘫或卒中发生。 16例腔内治疗病人中无严重并发症或死亡者。随访 48例 ,随访时间 1个月~ 15年 ,5例死亡 (10 4% )。保守治疗 46例中 ,44 1%死于瘤体破裂或其它严重并发症。结论 AAARA开胸手术仍存在着很大风险 ,而多种多样的支架型人工血管腔内置放和腔内开窗治疗有着良好前景 ,腔内血管外科技术将成为治疗AAARA的主流。  相似文献   
30.
Kidney and bladder stones (urinary tract stones) and osteoporosis are prevalent, serious conditions for postmenopausal women. Men with kidney stones are at increased risk of osteoporosis; however, the relationship of urinary tract stones to osteoporosis in postmenopausal women has not been established. The purpose of this study was to determine whether urinary tract stones are an independent risk factor for changes in bone mineral density (BMD) and incident fractures in women in the Women's Health Initiative (WHI). Data were obtained from 150,689 women in the Observational Study and Clinical Trials of the WHI with information on urinary tract stones status: 9856 of these women reported urinary tract stones at baseline and/or incident urinary tract stones during follow‐up. Cox regression models were used to determine the association of urinary tract stones with incident fractures and linear mixed models were used to investigate the relationship of urinary tract stones with changes in BMD that occurred during WHI. Follow‐up was over an average of 8 years. Models were adjusted for demographic and clinical factors, medication use, and dietary histories. In unadjusted models there was a significant association of urinary tract stones with incident total fractures (HR 1.10; 95% CI, 1.04 to 1.17). However, in covariate adjusted analyses, urinary tract stones were not significantly related to changes in BMD at any skeletal site or to incident fractures. In conclusion, urinary tract stones in postmenopausal women are not an independent risk factor for osteoporosis. © 2015 American Society for Bone and Mineral Research.  相似文献   
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