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81.
目的 探讨术中十二指肠镜下乳头切开术(IEPT)治疗胆石症合并的胆总管末端狭窄或细径胆总管结石的手术方法 和适应证.方法 腹腔镜下或开腹下完成胆囊切除术.粗径胆总管:胆总管切开探查并取净结石,经胆总管切口插入输尿管导管或斑马导丝至十二指肠腔,经口插入十二指肠镜至十二指肠乳头,针式刀或弓式刀在输尿管导管或斑马导丝指引下施行乳头切开术以治疗合并的胆总管末端狭窄.细径胆总管:经胆囊管残端插入输尿管导管或斑马导丝至十二指肠腔,经口插入十二指肠镜施行乳头切开术和取石术,用十二指肠镜取石网或球囊取石以治疗细径胆总管结石.结果 粗径胆总管:施行腹腔镜下IEPT 47例,45例乳头狭窄切开成功,2例中转为其他术式.施行开腹下IEPT5例,5例乳头狭窄切开成功.细径胆总管:施行腹腔镜下IEPT和取石术74例,68例乳头切开和取石成功,5例乳头切开成功,1例中转为其他术式.施行开腹下IEPT和取石术2例,2例乳头切开和取石成功.结论 只要选择合适的病例,1EPT在腹腔镜下或开腹下均是可行、有效和安全的.  相似文献   
82.
Performance of a perovskite solar cell is largely influenced by the optoelectronic properties of metal halide perovskite films. Here we study the influence of cesium concentration on morphology, crystal structure, photoluminescence and optical properties of the triple cation perovskite film. Incorporation of small amount (x = 0.1) of cesium cations into Csx(MA0.17FA0.83)1−x Pb(I0.83Br0.17)3 leads to enhanced power conversion efficiency (PCE) of the solar cell resulting mainly from significant rise of the short-current density and the fill factor value. Further increase of Cs concentration (x > 0.1) decreases the film’s phase purity, carrier lifetime and correspondingly reduces PCE of the solar cell. Higher concentration of Cs (x ≥ 0.2) causes phase segregation of the perovskite alongside with formation of Cs-rich regions impeding light absorption.  相似文献   
83.
《Dental materials》2022,38(12):2073-2083
ObjectivesThis study investigated potential variations in polymerisation of light- and dual-cured (LC and DC) resin cements photoactivated through four CAD/CAM restorative materials as a function of substrate thickness.MethodsFour CAD/CAM materials [two resin composites CeraSmart (CS) and Grandio Blocs (GB); a polymer infiltrated ceramic Vita Enamic (VE) and a feldspathic ceramic Vita Mark II (VM)], with five thicknesses (0.5, 1, 1.5, 2, and 2.5 mm) were prepared and their optical characteristics measured. 1 mm discs of LC and DC resin cement (Variolink® Esthetic, Ivoclar AG) were photoactivated through each specimen thickness. After 1 h post-cure, polymerisation efficiency was determined by degree of conversion (DC%) and Martens hardness (HM). Interactions between materials, thicknesses and properties were analysed by linear regressions, two-way ANOVA and one-way ANOVA followed by post hoc multiple comparisons (α = 0.05).ResultsAll substrates of 0.5- and 1.0-mm thickness transmitted sufficiently high peak irradiances at around 455 nm: (It = 588–819 mW/cm2) with translucency parameter TP = 21.14 – 10.7; ranked: CS> GB = VM> VE. However, increasing the substrate thickness (1.5–2.5 mm) reduced energy delivery to the luting cements (4 – 2.8 J/cm2). Consequently, as their thicknesses increased beyond 1.5 mm, HM of the cement discs differed significantly between the substrates. But there were only slight reduction of DC% in LC cements and DC cement discs were not affected.Significance: Photoactivating light-cured Ivocerin? containing cement through feldspathic ceramics and polymer-infiltrated ceramics achieved greater early hardness results than dual-cured type, irrespective of substrate thickness (0.5 – 2.5 mm). However, only 0.5 and 1 mm-thick resin composites showed similar outcome (LC>DC). Therefore, for cases requiring early hardness development, appropriate cement selection for each substrate material is recommended.  相似文献   
84.
经络综合导引治疗仪是根据祖国医学的经络学说和养气功理论,应用呼气启动导引,视觉模型提示和穴位电刺激的多因素共同作用,导引气血沿经络运行。主要用于强化瘫痪肢体的康复。该治疗仪以单片微机为程控中心,通过硬件设计和软件开发,实现了呼气触发,视觉提示和位电刺激同步发,16和电极依次选通和数字化幅度调节等多种功能。  相似文献   
85.
Sequence exchange between PMS2 and its pseudogene PMS2CL, embedded in an inverted duplication on chromosome 7p22, has been reported to be an ongoing process that leads to functional PMS2 hybrid alleles containing PMS2‐ and PMS2CL‐specific sequence variants at the 5′‐and the 3′‐end, respectively. The frequency of PMS2 hybrid alleles, their biological significance, and the mechanisms underlying their formation are largely unknown. Here we show that overall hybrid alleles account for one‐third of 384 PMS2 alleles analyzed in individuals of different ethnic backgrounds. Depending on the population, 14–60% of hybrid alleles carry PMS2CL‐specific sequences in exons 13–15, the remainder only in exon 15. We show that exons 13–15 hybrid alleles, named H1 hybrid alleles, constitute different haplotypes but trace back to a single ancient intrachromosomal recombination event with crossover. Taking advantage of an ancestral sequence variant specific for all H1 alleles we developed a simple gDNA‐based polymerase chain reaction (PCR) assay that can be used to identify H1‐allele carriers with high sensitivity and specificity (100 and 99%, respectively). Because H1 hybrid alleles harbor missense variant p.N775S of so far unknown functional significance, we assessed the H1‐carrier frequency in 164 colorectal cancer patients. So far, we found no indication that the variant plays a major role with regard to cancer susceptibility. Hum Mutat 31:1–8, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
86.
介绍基于USB2.0接口的医用超声内窥镜旋转扫描成像的设计与实现。根据超声成像的特点,本系统采取脉冲回波成像方式,文中介绍了超声波激发、接收电路以及收发隔离电路。针对旋转扫描的特点,设计了基于FPGA的同步控制电路和基于USB2.0接口的数据传输电路。对采集到的原始图像,进行坐标变换,获得了按直角坐标显示的灰度图像。利用连续旋转马达对实际物体扫描成像的实验结果,验证了系统的正确性。  相似文献   
87.
为解决鲤鱼脑组织坐标准确定位问题,本文提出一种将鲤鱼脑组织磁共振成像坐标转换为应用脑立体定位仪进行电极植入所需坐标的方法。本研究应用3.0T磁共振成像仪对鲤鱼颅脑成像,自主建立颅脑三维立体定位坐标系、颅骨表面辅助三维坐标系和脑组织内部辅助三维坐标系,经两次坐标转换,将脑电极植入位点磁共振图像坐标转换到三维立体定位坐标系中以引导电极植入。实验分A、B两组,A组为磁共振成像仪结合脑立体定位仪组,B组为脑图谱结合脑立体定位仪组,每组鲤鱼20尾(n=20),分别应用两种方法将电极植入小脑运动区。进行鲤鱼机器人水下实验检验,结果表明A组和B组植入电极准确度分别为90%和60%,A组成功率明显高于B组(P <0.05)。故本文的新方法能够准确定位鲤鱼脑组织的坐标。  相似文献   
88.
目的探讨腹腔镜辅助的子宫内膜癌手术与传统开腹手术临床效果的差异。方法回顾性研究2007年1月至2010年3月在上海交通大学附属第一人民医院妇科行子宫内膜癌腹腔镜手术的51例患者临床资料,选择同期同组医生施行的子宫内膜癌传统开腹手术69例作为对照组,比较两组临床效果。结果腹腔镜组与开腹组在手术时间、术中清扫淋巴结数目上差异无统计学意义。腹腔镜组术中失血少、术后发热率低、肠道恢复快、住院时间短,与开腹组差异有统计学意义(P<0.05)。开腹组切口裂开率高于腹腔镜组,而其他并发症组间差异无统计学意义。结论腹腔镜手术是治疗早期子宫内膜癌稳妥可行的选择。  相似文献   
89.
Stille coupling polymerization is used to synthesize a new donor–acceptor (D–A) conjugated random copolymer (PBDT‐DFB‐DPP) that comprises an electron‐rich benzodithiophene (BDT) unit in conjugation with electron‐deficient 2,5‐difluorobenzene (DFB) and diketopyrrolopyrrole (DPP) moieties, which have complementary light‐absorption behavior. The thermal, photophysical, and electrochemical properties of the polymer are investigated using thermogravimetric analysis, UV–vis absorption spectroscopy, and cyclic voltammetry. The random copolymer exhibits both broad light absorption and a low‐lying highest occupied molecular orbital (HOMO) level, which contribute to enhancement of the short‐circuit current density (Jsc) and open‐circuit voltage (Voc). A bulk‐heterojunction polymer solar cell fabricated from PBDT‐DFB‐DPP and PC60BM exhibits a promising power conversion efficiency (PCE) of 2.50%.

  相似文献   

90.
Treatment of multidrug-resistant tuberculosis (MDR-TB), defined as Mycobacterium tuberculosis resistant to both isoniazid and rifampicin, is challenging under the best of circumstances, and particularly in resource-limited settings. For patients who remain persistently sputum-culture-positive despite therapy with second-line TB drugs, treatment options are limited, especially if disease is too advanced for resective surgery. Salvage therapy refers to the design of a regimen combining new and previously used drugs in a final effort to attain sputum conversion before declaring treatment to have failed. We retrospectively evaluated the outcomes of salvage therapy in 213 Peruvian patients. Salvage regimens included a median of two new drugs (range 1–6) and nine (range 5–13) total (new plus previously used) drugs. The most frequently used new drug was moxifloxacin, followed by capreomycin, amoxicillin-clavulanate, kanamycin and clarithromycin. Culture conversion occurred in 65 (30.5%) patients. Salvage regimens that included moxifloxacin were significantly more likely to be followed by culture conversion (OR 2.2; p 0.02). Later-generation fluoroquinolones such as moxifloxacin should be used in salvage therapy but also in the initial treatment of MDR-TB, if the best clinical strategy is to use the most effective drugs when the patient has the best chance for cure. New TB drugs are most likely to be initially used in salvage patients, in conditions similar to those described here. Close bacteriological monitoring of these patients will be essential, as useful information about the best way to use these new drugs can be gained from analysis of salvage therapy cohorts.  相似文献   
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