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1.
《International journal of oral and maxillofacial surgery》2022,51(4):552-557
The aim of this retrospective study was to investigate the accuracy of dynamic navigation for the placement of intentionally tilted implants in the posterior maxilla. The study included 12 patients with edentulism or continuous multiple tooth loss, who had 48 implants inserted under dynamic navigation guidance in the posterior maxilla. Twenty-four implants near maxillary sinuses were intentionally tilted. The average platform deviation was 1.3 ± 0.4 mm (range 0.8–2.3 mm), apex deviation was 1.1 ± 0.5 mm (range 0.2–2.3 mm), and axis deviation was 3.1 ± 1.0° (range 1.8–6.7°). The other 24 implants were axially positioned. The average platform deviation was 1.5 ± 0.5 mm (range 0.7–3.1 mm), apex deviation was 1.3 ± 0.7 mm (range 0.5–3.1 mm), and axis deviation was 3.2 ± 1.5° (range 1.5–7.7°). There was no significant difference in platform deviation, apex deviation, or axis deviation between the tilted implants and implants in the axial position (P > 0.05). This analysis indicates that a dynamic navigation system can be used as a method of guidance to place intentionally tilted implants as accurately as axially positioned implants in the posterior maxilla, thereby preventing damage to the maxillary sinuses and the need to graft bone. 相似文献
2.
Aldo Cannata Silvia Cantoni Antonio Sciortino Giuseppe Bruschi Claudio Francesco Russo 《Journal of the American College of Cardiology》2021,77(18):2323-2334
Mechanical intravascular hemolysis is frequently observed following procedures on heart valves and uncommonly observed in native valvular disease. In most cases, its severity is mild. Nevertheless, it can be clinically significant and even life threatening, requiring multiple blood transfusions and renal replacement therapy. This paper reviews the current knowledge on mechanical intravascular hemolysis in valvular disease, before and after correction, focusing on pathophysiology, approach to diagnosis, and impact of other hematological conditions on the resultant anemia. The importance of a multidisciplinary management is underscored. Laboratory data are provided about subclinical hemolysis that is commonly observed following the implantation of surgical and transcatheter valve prostheses and devices. Finally, clinical scenarios are reviewed and current medical and surgical treatments are discussed, including alternative options for inoperable patients. 相似文献
3.
《Vaccine》2021,39(14):1933-1942
The genetic and antigenic drift associated with the high pathogenicity avian influenza (HPAI) viruses of Goose/Guangdong (Gs/GD) lineage and the emergence of vaccine-resistant field viruses underscores the need for a broadly protective H5 influenza A vaccine. Here, we tested experimental vector herpesvirus of turkey (vHVT)-H5 vaccines containing either wild-type clade 2.3.4.4A-derived H5 inserts or computationally optimized broadly reactive antigen (COBRA) inserts with challenge by homologous and genetically divergent H5 HPAI Gs/GD lineage viruses in chickens. Direct assessment of protection was confirmed for all the tested constructs, which provided clinical protection against the homologous and heterologous H5 HPAI Gs/GD challenge viruses and significantly decreased oropharyngeal shedding titers compared to the sham vaccine. The cross reactivity was assessed by hemagglutinin inhibition (HI) and focus reduction assay against a panel of phylogenetically and antigenically diverse H5 strains. The COBRA-derived H5 inserts elicited antibody responses against antigenically diverse strains, while the wild-type-derived H5 vaccines elicited protection mostly against close antigenically related clades 2.3.4.4A and 2.3.4.4D viruses. In conclusion, the HVT vector, a widely used replicating vaccine platform in poultry, with H5 insert provides clinical protection and significant reduction of viral shedding against homologous and heterologous challenge. In addition, the COBRA-derived inserts have the potential to be used against antigenically distinct co-circulating viruses and future drift variants. 相似文献
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5.
目的:探讨二补助育汤对胚胎着床障碍模型小鼠子宫内膜形态及血管生成素-1(Ang-1)mRNA、血管内皮生长因子(VEGF)mRNA的表达和定位的影响。方法:24只ICR雌性小鼠随机分为空白组、模型组、戊酸雌二醇组、二补助育汤组,每组6只,用米非司酮建立胚胎着床障碍动物模型,各组给予相应药物灌胃,妊娠第5天处死小鼠后,检测各组妊娠率、平均着床位点数、子宫内膜Ang-1和VEGF mRNA表达量及其蛋白定位。结果:模型组小鼠平均胚胎着床位点数、Ang-1 mRNA、VEGF mRNA表达量明显低于空白组(均P<0.05);与模型组比较,二补助育汤组平均胚胎着床位点数、Ang-1 mRNA、VEGF mRNA表达量显著提高(均P<0.05)。结论:二补助育汤可提高子宫内膜Ang-1和VEGF蛋白表达量,促进子宫内膜血管生成,从而提高子宫内膜容受性。 相似文献
6.
胚胎植入是一个复杂且受到高度调控的过程,需要囊胚与母体子宫内膜的发育精确同步。胞饮突作为表达于子宫内膜上的一种特殊膜状突起,随月经周期变化表现为不同形态,可分为发育期、成熟期及退化期。目前已有一系列研究证实,胞饮突的数量、覆盖面积及发育阶段等在预测不孕女性种植窗及评估子宫内膜容受性中具有临床价值。胞饮突评分较高、覆盖面积较广且成熟期胞饮突占比较高的女性妊娠结局更佳。其机制可能包括胞饮突通过调节宫腔内容物影响子宫内膜容受性、通过表达植入相关蛋白参与囊胚-子宫内膜相互作用等。然而,对胞饮突精准且客观的评估手段仍待进一步探索,胞饮突评估子宫内膜容受性的精确度也待进一步验证。 相似文献
7.
目的探讨胆总管结石患者采用内镜逆行胰胆管造影术(ERCP)取石后同期开展胆道支架置入术或开展经内镜鼻胆管引流术(ENBD),对于防范并发症的价值。
方法按照前瞻性研究原则,选择2017年4月至2019年1月新疆医科大学第一附属医院收治的338例胆总管结石患者,随机分为支架组(170例)与引流组(168例)。两组患者均行ERCP治疗,其中引流组术后同期开展ENBD,支架组患者术后开展胆道支架置入术,对比两组患者腹痛评分、并发症发生情况及预后。
结果两组患者术后均未合并严重出血、穿孔或病死,结石完全清除率差异无统计学意义。与支架组相比,引流组术中胰腺管插管次数,术后4 h血淀粉酶水平、高淀粉酶血症、急性胰腺炎以及并发症总发生率更高,差异有统计学意义(P<0.05),术后24、48、72 h不同时点腹痛测评分值居更高水平(P<0.05)。
结论对于胆总管结石行ERCP治疗的患者,术后予以ENBD、胆道支架置入术的结石完全清除效果对比无明显差异,但胆道支架置入术更能降低术后并发症风险、缓解腹痛症状,患者获益更多。 相似文献
8.
9.
Perry Maskell Mika Burgess Beverly MacCarthy‐Ofosu Amer Harky 《Journal of cardiac surgery》2019,34(5):239-249
Cardiovascular disease represents a significant portion of pregnancy‐related complications and is associated with high rates of morbidity and mortality in this cohort. Cardiac valvulopathy, and aortic valve pathologies, in particular, pose a significant challenge to women who are pregnant and to the health care professionals who look after them. Depending on the type and severity of aortic valve pathology, pregnancy may exacerbate or accelerate the progression of valvulopathy sequelae because of the hemodynamic changes that occur from conception, throughout gestation, up to Labor and postpartum. Management of such patients ranges from basic conservative measures such as bed‐rest, extending to high‐risk emergency open heart surgery. This nonstructured review aims to highlight the current evidence available relating to the management of aortic valve disease in pregnancy, with a key focus on cases which requires intervention beyond that of medical therapy. In conclusion, the management of aortic valvulopathy in pregnancy is a challenging field with only a small amount of clinical experience and retrospective study supporting evidence‐based decisions in this field. A greater understanding of the most recent advances is recommended to support decision making in this specialist field of clinical medicine. 相似文献
10.
目的提高耳科疾病患者手术护理质量与效率。方法按时间段将耳科手术患者400例分为两组各200例;对照组按常规进行手术护理配合;观察组构建耳科手术护理配合标准作业程序(SOP),对护士进行专项培训后用于手术护理中。比较耳蜗植入、中耳手术、听神经瘤手术及咽鼓管球囊扩张4项手术的应用效果。结果观察组前3项手术时间显著短于对照组;手术医生满意度显著高于对照组,因手术器械仪器故障致手术中断率显著低于对照组(P0.05,P0.01)。结论构建的耳科手术护理配合SOP使手术护理规范化、标准化、同质化,有效提高了手术室护理工作效率及护理质量。 相似文献