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排序方式: 共有1128条查询结果,搜索用时 15 毫秒
1.
目的:评价快速康复(fast track,FT)模式在不同方式胃癌根治手术患者术后康复中的有效性及安全性。方法:收集我科2016年1月至2017年6月期间行开放(OS)及腹腔镜(LS)胃癌根治手术患者各40例,随机分为FT处理组(OS+FT组、LS+FT组)和常规处理(NT)对照组(OS+NT组、LS+NT组),比较不同处理模式对术后疼痛评分、恢复情况和术后并发症发生率的影响。结果:OS+FT组、LS+FT组术后1、2、3、4和5 d疼痛评分均低于NT对照组,各观察时点差异均有统计学意义(P<0.005);OS+FT组、LS+FT组术后首次排气时间、首次离床时间以及住院时间均短于NT对照组(P<0.05);术后OS+FT组、LS+FT组总体并发症发生率均为10%,与NT对照组(OS+NT组20%,LS+NT组15%)相比,差异无统计学意义(P>0.05)。结论:FT模式有利于减少患者痛苦,加速术后恢复,未增加术后并发症风险,在不同方式胃切除手术患者围术期处理过程中安全、有效。  相似文献   
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The leaves of Rubus suavissimus (also called “Chinese sweet tea”) is used not only as a beverage tea and food additive but also as a folk herbal medicine for the treatment of diabetes mellitus. To systematically investigate its material foundation of efficacy for treating diabetes, herein, a hyphenated strategy by off-line coupling high-speed countercurrent chromatography, ultrafiltration HPLC-UV-MS and prep-HPLC was developed. And thus, α-glucosidase inhibitors from Rubus suavissimus leaves was comprehensively profiled, purified and characterized. As a result, twenty-six compounds were identified as potential α-glucosidase inhibitors and favorably isolated by prep-HPLC. Their structures were identified via UV, MS, and 1H-NMR. Notably, fourteen compounds, including protocatechuic acid (1), myketin (3), epicatechin (4), vanillic acid (6), apigenin (11), catechin (12), ferulic acid (15), luteolin (16), 3, 3′-di-O-methylellagic acid (17), chlorogenic acid (19), 3, 3′-di-O-methylellagic acid-4′-O-β-D-glucoside (20), cinnamic acid (21), syringate (24) and ethylbrevifolin-carboxylate (25), were reported in leaves of Rubus suavissimus for the first time. In addition, α-glucosidase inhibitory activities of compounds 1–26 were evaluated, and eighteen compounds exhibited stronger α-glucosidase inhibitory activities than acarbose (IC50 value at 214.24 ± 3.48 μg/mL, positive control). The results indicated that the proposed method is a highly efficient strategy for comprehensive profiling and purification of bioactive target compounds, including both major and minor components, from natural products.  相似文献   
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Nearby grid cells have been observed to express a remarkable degree of long‐range order, which is often idealized as extending potentially to infinity. Yet their strict periodic firing and ensemble coherence are theoretically possible only in flat environments, much unlike the burrows which rodents usually live in. Are the symmetrical, coherent grid maps inferred in the lab relevant to chart their way in their natural habitat? We consider spheres as simple models of curved environments and waiting for the appropriate experiments to be performed, we use our adaptation model to predict what grid maps would emerge in a network with the same type of recurrent connections, which on the plane produce coherence among the units. We find that on the sphere such connections distort the maps that single grid units would express on their own, and aggregate them into clusters. When remapping to a different spherical environment, units in each cluster maintain only partial coherence, similar to what is observed in disordered materials, such as spin glasses.  相似文献   
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《Foot and Ankle Surgery》2022,28(8):1163-1169
The post-operative results of a total ankle replacement are not determined solely by an optimal surgical technique, but by an appropriate anesthesiological and rehabilitative post-operative approach. Enhanced functional recovery often depends on a multidisciplinary approach based on a correct framework of the patient and his needs, requests, and characteristics.Extensive bibliographical research has been performed on Pubmed, Google Scholar, Scopus.This comprehensive and inclusive review of the literature aims to examine the state of the art of “fast-track” protocols employed in total ankle replacement (TAR), considering pre-operative preparation, anesthetic management, intraoperative and surgical factors, post-operative rehabilitative care and reduction of hospitalization time.  相似文献   
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IntroductionThe purpose of this study was to assess the optimal amplitude and weight of the newly developed contra-angle handpiece. The handpiece uses piston movement without using an endodontic motor and enables a safe, quick, and reliable canal preparation.MethodsA prototype handpiece was designed. Instrumentation was performed on root canal resin blocks by 20 operators in 3 groups: the prototype handpiece with an H file (a stainless steel #25 manual H file, the piston group), a manually standardized technique with a K file (stainless steel #15–25 K files, the manual group), and a nickel-titanium (NiTi) reciprocating file with an endodontic motor (Reciproc Blue R25 [VDW, Munich, Germany], the NiTi group). Transportation of the canal center line and the time required for preparation were measured and statistically analyzed.ResultsThe optimal condition was an amplitude of 1.35 mm and a weight of 61.0 g. Transportation of the canal center was observed in all groups. A statistically significant difference was found at 2.0–3.0 mm from the apical foramen between the piston or NiTi group and the manual group, but no significant difference was found between the piston and NiTi groups. The least transportation was found in the NiTi and piston groups. The handpiece with a #25 H file demonstrated a good centering ability, similar to the NiTi file, which enabled speedy preparation. The time required for preparation between the piston or NiTi group and the manual group was statistically different. No significant difference was observed between the piston and NiTi groups (P < .05).ConclusionsWe concluded that the newly designed handpiece achieved efficient canal preparation and negotiation. The handpiece could avoid endodontic accidents, including ledge formation, instrument separation, and perforation.  相似文献   
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目的探讨逐步后退法、逐步深入法、被动逐步后退法(超声波与手用器械联合应用、三种不同方法预备后牙细弯根管对根管壁的清理能力及操作时间的差别。方法应用逐步后退法、逐步深入法、被动逐步后退法(超声波与手用器械联合应用)对45个新鲜拔除的人恒磨牙近中颊侧根管进行预备.并记录操作时间,将牙根纵向劈开,分为根冠1/3、根中1/3及根尖1/3,扫描电镜下评价其根管内壁牙本质碎屑和玷污层的形成情况。结果三种方法对根管清理能力差异无统计学意义(P〉0.05)而无论使用何种预备方法,其对根中1/3及根冠1/3处的清理能力优于根尖1/3部.两者差异有统计学意义(P〈0.05)。3种方法根管预备时间分别为:逐步后退法(12.8±1.26)min.逐步深入法(9.02±0.74)min,被动逐步后退法(超声与手用器械联合应用法)(12.21±1.90)min.三组差异无统计学意义(P〉0.05)。结论三种根管预备方法均不能达到完全的根管清理,尤其是对于根尖1/3部,清洁效果很不理想:总体上看,根中及根冠1/3清洁度显著优于根尖1/3。被动逐步后退法(超声与手用器械联合应用)及逐步后退法操作均较费时、费力,而逐步后退法根管预备时间略短于另两种方法且较省力。  相似文献   
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AIM: To compare the shaping ability of progressive versus constant taper shaft instruments in curved root canals of extracted human teeth. METHODOLOGY: A total of 40 root canals of mandibular molars with curvatures ranging between 20 degrees and 40 degrees were divided into two groups of 20 canals each and embedded in a muffle system. The root canals sectioned horizontally at three levels before preparation and then remounted into the mould. All root canals were prepared with ProTaper (progressive taper) or Hero Shaper (constant taper) instruments. Pre- and post-instrumentation radiographs and cross-sectional images were obtained. The parameters evaluated were: working safety (instrument failure, apical blockage and loss of working length) and shaping ability (straightening, cross-sectional area, transportation and centring ability). The data were analysed statistically using Student's t-test. RESULTS: No instrument fractured during preparation. One Hero Shaper instrument permanently deformed. Both instrument systems maintained working length well. The canals prepared with Hero Shaper instruments were straightened to a lesser degree (P < 0.05). ProTaper instruments removed more dentine in the coronal and the middle sections of the canals. Canals prepared with Hero Shaper instruments had less transportation (P < 0.01) and better centring ability (P < 0.05) in the apical section. CONCLUSIONS: Both instrument systems were safe to use and maintained working length well. The canals prepared with Hero Shaper had less transportation and were better centred in the apical region, possibly because their smaller taper reduced instrument stiffness.  相似文献   
9.
多排CT曲面重建在颌骨病变诊断与治疗中的评价   总被引:1,自引:1,他引:1  
目的:利用多排CT扫描后可行上、下颌骨全景曲面重建的特点,探讨多排CT曲面全景片对颌骨疾病的诊断价值及指导临床手术的应用价值.方法:自2002.3.以来,对29例上、下颌骨疾病(包括上、下颌骨囊肿22例、颌骨骨髓炎2例、牙龈癌5例)行16排螺旋CT扫描,扫描层厚0.625mm或1.25mm,将扫描数据传至工作站(GE公司advantageworkstation,AW4.0),对上、下颌骨行不同层面的曲面断层重建,贮存图像并对图像进行分析.同时用X光机拍摄口腔全景片,将二种全景片进行阅片对比.结果:多排CT曲面断层全景片清晰,能清楚显示骨质的细微变化、骨病变的范围及其与周围组织及器官(如牙齿、上颌窦、下齿槽神经管)的关系,无颊舌侧骨组织覆盖影,其图像对疾病的定性诊断具有明确的指导价值,而X线口腔全景片有影像失真,在病变处存在颊舌侧骨质相互重叠影.结论:多排CT口腔全景断层片能非常清晰地显示骨病变与周围组织及牙齿的关系,可显示骨质的细微变化,无放大失真,对颌骨病变的定性诊断、病变范围的界定结果可靠.对临床医师在疾病的诊断,术前手术方案的制订有重要的指导价值.  相似文献   
10.
The purpose of this study was to estimate the length of the occlusal glide during gum chewing at the lower incisal point. Mandibular excursions with occlusal contacts in 25 females with permanent dentition were recorded using an optoelectronic system that can measure mandibular movement with 6 d.f. at a sampling frequency of 100 Hz. A curved mesh diagram of incisor coordinates during maximum mandibular excursions (CMDME) was plotted. Gum chewing movement was also measured using the same system and computer software which divided the chewing movement into cycles at each maximum opening position. Each cycle was standardized at 0.1 mm intervals from the most closed position. Finally, the distance between the CMDME and each position of the incisor during a chewing cycle was calculated. Whenever, this distance was less than 0.2 mm opposing teeth were considered to be in contact. The occlusal glide was defined as the distance travelled by the lower incisal point as the mandible moved along occlusal contacts of the CMDME. The vertical coordinates at the beginning of the occlusal glide (during closing) and at the end of occlusal glide (during opening) were also calculated. The lengths of the occlusal glide pathway averaged 1.29 mm during closing and 1.55 mm during opening, a total length of 2.84 mm. Mean vertical coordinates at the beginning and end of the glide were -0.95 and -1.12 mm from intercuspal position, respectively.  相似文献   
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