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991.
目的 观察两种玻璃纤维桩修复系统修复牙齿缺损的短期临床疗效。方法 选择北京宣武中医医院口腔科门诊和北京大学口腔医院特诊科因牙体缺损进行桩核冠修复的符合纳入标准的120例患者,经知情同意后,随机分2组,每组 60例,分别采用 Tenax Fiber White纤维桩与国产 OUYA FIBER纤维桩修复系统修复,修复后 1周与 3个月复诊,检查纤维桩修复的临床效果。结果 Tenax Fiber White纤维桩与OUYA FIBER纤维桩修复1周后,检查纤维桩修复体的总体情况、边缘密合性、边缘着色情况,两组满意率均达到 98%以上;3个月后复查,通过 X线片检查纤维桩的总体情况和基牙情况,以及咀嚼功能恢复情况,两组满意率均达到 96%以上;2组间比较差异无统计学意义(P>0.05)。结论 OUYA FIBER纤维桩与Tenax Fiber White纤维桩在3个月的观察期间的总体疗效相当,值得推广应用,但仍需对其疗效进行长期的临床观察。  相似文献   
992.
Anthropogenic factors have contributed to a severe decline of Leptobotia elongata. Conservation information of L. elongata will be required. Here, 14 tetranucleotide microsatellite DNA markers were developed from L. elongata through high-throughput (454) sequencing data. Twenty-four individuals of the species were genotyped using these markers. All of the loci displayed a high level of polymorphism with the number of alleles per locus ranged from 7 to 23, polymorphism information content ranged from 0.650 to 0.943. Observed and expected heterozygosities ranged from 0.609 to 1.000 and from 0.699 to 0.967, respectively. These markers provide an excellent toolkit to study population genetic structure and would benefit the conservation of this species.  相似文献   
993.
目的:探讨基于第3代双源CT动态心肌灌注成像(CT-MPI)定量的正常心肌血流量(MBF)与负荷后心率增量的关系。方法:回顾性分析2016年10月至2019年11月于上海交通大学附属第六人民医院行动态CT-MPI及冠状动脉CTA(CCTA)检查的冠状动脉正常或冠状动脉轻微狭窄(定义为任一心外膜血管直径狭窄<25%)44...  相似文献   
994.
目的 比较单纯使用关节镜治疗与联合使用富血小板血浆(PRP)的疗效,为肩袖损伤的治疗方法提供循证依据.方法 检索CENTRAL、Medline、PubMed、EMbase、CNKI、万方、维普、CBM数据库和手工检索会议文献等.通过制定纳入标准及排除标准纳入记录相关的随机对照试验的文献.检索时间均从该库建库始至2019...  相似文献   
995.
目的:探讨80 kV管电压联合个体化对比剂低剂量注射方案行颈动脉CT血管成像的可行性。方法:前瞻性纳入需要行颈部CT血管成像(CTA)检查的136名患者,采用完全随机区段法分成A、B、C、D 4组,A组为100 kV 15 s团注常规组,53例;其他3组为80 kV 10 s团注对照组,根据≤50 kg、50~70 k...  相似文献   
996.
目的 观察海藻酸钠 -氯化钡微囊对大鼠胰岛体外胰岛素分泌功能有无影响。方法 以海藻酸钠和氯化钡为材料 ,采用气体吹喷制囊法将新鲜分离纯化的大鼠胰岛制成微囊化胰岛 ,取空微囊、微囊化大鼠胰岛与未微囊化大鼠胰岛各 5 0 0只 ,分为 10份 ,置于培养板中培养 ,用放免法测定并比较第 2、4、6 d培养液中基础胰岛素浓度。结果 空微囊组第 2、4、6 d的基础胰岛素平均浓度均为 0 nm ol/ 1/ 5 0 ,微囊化大鼠胰岛组第 2、4、6 d的基础胰岛素平均浓度为 5 .179、5 .80 6、5 .5 5 8nm ol/ 1/5 0只 ,未微囊化大鼠胰岛组第 2、4、6 d的基础胰岛素平均浓度为 5 .4 4 1、6 .0 80、5 .4 6 8nmol/ 1/ 5 0只 ,后两者差异无显著性意义 (P>0 .0 5 )。结论 海藻酸钠 -氯化钡微囊对大鼠胰岛体外胰岛素分泌功能无影响  相似文献   
997.

Aim

To assess the efficacy of the multidisciplinary care (MDC) model for patients with chronic kidney disease (CKD).

Background

The MDC model has been used in clinical practice for years, but the effectiveness of the MDC model for patients with CKD remains controversial.

Methods

Embase, PubMed, Medline, the Cochrane Library, and China National Knowledge Infrastructure databases were used to search for relevant articles. Only randomized controlled trials and cohort studies were pooled. Two independent authors assessed all articles and extracted the data. The efficacy was estimated from the odds ratios and corresponding 95% confidence intervals. A random effects model was used according to the heterogeneity.

Results

Twenty-one studies including 10,284 participants were analyzed. Compared with the non-MDC group, MDC was associated with a lower risk of all-cause mortality and lower hospitalization rates for patients with CKD. In addition, MDC also resulted in a slower eGFR decline and reduced temporary catheterization for patients receiving dialysis. However, according to the subgroup analysis, the lower rates of all-cause mortality in the MDC group were observed only in patients in stage 4–5 and when the staff of the MDC consisted of nephrologists, nurse specialists and professionals from other fields. The most prominent effect of reducing the hospitalization rates was also observed in patients with stage 4–5 but not in patients with stage 4–5 CKD.

Conclusions

MDC can lower the all-cause mortality of patients with CKD, reduce temporary catheterization for patients receiving dialysis, decrease the hospitalization rate, and slow the eGFR decline. Moreover, the reduction in all-cause mortality crucially depends on the professionals comprising the MDC staff and the stage of CKD in patients. In addition, the CKD stage influences the hospitalization rates.
  相似文献   
998.

Objective

Arteriovenous fistula (AVF) suffers from a high number of failures caused by insufficient outward remodeling and venous neointimal hyperplasia formation. The aim was to investigate the exact mechanism by which microRNA-155 (miR-155) in the outflow vein of AVF is regulated.

Methods

AVFs between the branch of the jugular vein and carotid artery in an end-to-end manner were created in C57BL/6 and miR-155?/? mice with a C57BL/6 background. The venous segments were harvested at day 7, 14, 21, and 28, and the AVFs were analyzed histologically and at a messenger RNA level using real-time quantitative polymerase chain reactions. The outflow vein of AVF and the normal great saphenous vein, collected from patients with chronic kidney disease and coronary artery bypass surgery, were analyzed by histologic and molecular biologic approaches.

Results

Venous neointimal hyperplasia is significantly alleviated in miR-155?/? mice, and the expression of several chemokines and cytokines in the vessel wall, including regulated on activation, normal T-cell expressed and secreted factor (RANTES), monocyte chemoattractant protein 1, and vascular endothelial growth factor, was inhibited. miR-155 promoted the RANTES expression of smooth muscle-like cells, which in turn facilitated cell proliferation and extracellular matrix production.

Conclusions

miR-155 enhances venous neointima formation through the autocrine and paracrine effects of smooth muscle-like cell-derived RANTES in a nuclear factor κB-dependent manner during the entire AVF process, especially at the advanced stage.  相似文献   
999.
Recent improvements in isolated islet transplantation indicate that this therapy may ultimately prove applicable to patients with type I diabetes. An obstacle preventing widespread application of islet transplantation is an insufficient supply of cadaveric pancreata. Non-heart-beating donors (NHBDs) are generally not deemed suitable for whole-organ pancreas donation and could provide a significant source of pancreata for islet transplantation. Isolated pancreatic islets prepared from 10 NHBDs were compared with those procured from 10 brain-dead donors (BDDs). The success of the isolation for the two groups was analyzed for preparation purity, quality, and recovered islet mass. The function of NHBD and BDD islets was evaluated using in vitro and in vivo assays. On the basis of the results of this analysis, an NHBD isolated islet allograft was performed in a type I diabetic. The recovery of islets from NHBDs was comparable to that of control BDDs. In vitro assessment of NHBD islet function revealed function-equivalent BDD islets, and NHBD islets transplanted to non-obese diabetic-severe combined immunodeficient (NOD-SCID) mice efficiently reversed diabetes. Transplantation of 446,320 islet equivalents (IEq) (8,500 IEq/kg of recipient body weight) from a single NHBD successfully reversed the diabetes of a type I diabetic recipient. Normally functioning pancreatic islets can be isolated successfully from NHBDs. A single donor transplant from an NHBD resulted in a state of stable insulin independence in a type I diabetic recipient. These results indicate that NHBDs may provide an as yet untapped source of pancreatic tissue for preparation of isolated islets for clinical transplantation.  相似文献   
1000.

Background

The stability of acetabulum reconstructions using reinforcement rings and hooks is important for successful replacement surgery. The objective of this study was to biomechanically determine the effects of the hook on stress and the related micromotions of the acetabular reinforcement ring during the immediate postoperative period.

Methods

Acetabular reinforcement ring models were developed using a nonlinear, three-dimensional, finite element method. Using a pre-prepared template, we constructed without-hook and bone graft models of varying volumes and material properties.

Results

The stress on the inferior margin of the acetabulum was higher in the with-hook model than in the without-hook model, especially with increased bone graft volumes, and the stiffness of the bone graft material was decreased. Relative micromotions in the without-hook model were higher than in the with-hook models. The highest relative micromotion was observed in the model with increased bone graft volume and lower stiffness of bone graft material.

Conclusions

In biomechanical analyses, the hook effectively dispersed stress and improved the initial fixation strength of the acetabular reinforcement ring.
  相似文献   
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