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Poly(phenylene ethynylene)‐alt‐poly(phenylene vinylene)s (PPE‐PPVs) with various thiophene units (thiophene, bithiophene, and 3,4‐ethylenedioxythiophene) at the X position, with the general backbone design (Ph? C?C? X ? C?C? Ph? CH?CH? Ph? CH?CH? ), bearing identical solubilizing side chains at the phenylene rings of the polymers, are synthesized to study the effect of this structural alteration on the properties such as the photophysics, the electrochemical properties, the charge‐carrier mobility, and the morphology of the materials and its impact on their photovoltaic performance. The polymers are obtained in good yields with reasonable molecular weights and show solubility in ordinary organic solvents required for solution‐processing applications. The polymer with a basic thiophene ring at the X positions shows the highest open‐circuit voltage (VOC of 930 mV) and the polymer with a bithiophene unit at the X position shows the highest short‐circuit current density and charge‐carrier mobility, whereas the polymer with 3,4‐ethylenedioxythiophene shows the lowest photovoltaic performance.

  相似文献   

3.
Background: Brief procedures that reduce smoking behaviour may be useful in reaching the many people that do not seek help for smoking addiction.

Objectives: The current study aimed to determine if one component of Acceptance and Commitment Therapy (ACT), cognitive defusion, could be useful in reducing smoking behaviour in a sample of students.

Methods: The study employed a between-subjects three-arm design. For one week, participants were asked to reduce their cigarette consumption. To aid them in their reduction, participants were randomly allocated to one of three conditions: the first received a defusion procedure, the second received an experiential avoidance procedure and a control condition received no procedure. For a second week, the instruction to reduce cigarette consumption was lifted. During both weeks participants were required to monitor their smoking behaviour via a tally diary system.

Results: The defusion condition smoked significantly less than the control condition during week one and significantly less than the control and experiential avoidance conditions during week two.

Conclusion: Results are discussed in terms of the potential utility of defusion in this domain, and the limitations of this preliminary research that would need to be addressed in future investigations.  相似文献   

4.
The aim of this randomized, parallel, controlled clinical trial was to examine the clinical and biochemical efficacy of diode laser as an adjunct to scaling and root planing (SRP). Thirty chronic periodontitis patients were randomly assigned into two groups to receive SRP alone (control) or SRP followed by diode laser (test). Plaque index, gingival index, bleeding on probing, probing depth, and clinical attachment level were measured at baseline and at 1, 3, and 6 months after treatment. The gingival crevicular fluid levels of interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8), matrix metalloproteinase-1 (MMP-1), matrix metalloproteinase-8 (MMP-8) and tissue inhibitor matrix metalloproteinase-1 (TIMP-1) were analyzed by enzyme-linked immunosorbent assay. Test group showed significantly a better outcome compared to the control group in full-mouth clinical parameters. MMP-1, MMP-8, and TIMP-1 showed significant differences between groups after treatment compared to baseline (p?<?0.05). The total amount of IL-1β, IL-6, MMP-1, MMP-8, and TIMP-1 decreased (p?<?0.05) and IL-8 increased after treatment in both test and control groups (p?<?0.05). Diode laser provided significant improvements in clinical parameters and MMP-8 was significantly impacted by the adjunctive laser treatment at first month providing an insight to how lasers can enhance the outcomes of the nonsurgical periodontal therapy.  相似文献   
5.
目的:探讨即刻乳房假体重建(一步法)和应用扩张器的假体重建(二步法)两种不同手术方式在术后并发症、美容效果和成本效益的差异。方法:回顾性分析我院乳腺外科2015年5月至2018年5月收治的285例乳腺癌植入物重建患者,依据手术方式不同分为一步法组(145例)和二步法组(140例),比较两组患者临床资料的差异。结果:一步法组术后出血发生率(6.8%)高于二步法组(1.4%),差异有统计学意义(P=0.021)。一步法组术后伤口皮瓣坏死率(6.2%)高于二步法组(1.4%),差异有统计学意义(P=0.036)。二步法组乳房满意度评分(81.5±7.1)分高于1步法组(78.6±6.2)分,差异有统计学意义(P=0.035)。二步法组住院总花费(80 334.8±6 149.8)元高于一步法组(60 966.5±5 544.9)元,差异有统计学意义(P=0.049)。二步法组住院天数(34.3±3.2)天多于一步法组(17.5±3.9)天,差异有统计学意义(P=0.014)。结论:在植入物乳房重建两种手术方式中,二步法相较于一步法,其并发症少,美容效果好,但在成本效益上并不优于一步法。  相似文献   
6.
Treatment of in-stent restenosis (ISR) with conventional percutaneous transluminal coronary angioplasty (PTCA) causes significant recurrent neointimal tissue growth in 30-85%. Therefore, laser ablation of intrastent neointimal hyperplasia before balloon dilation can be an attractive alternative. However, the long-term outcomes of such treatment have not been studied thoroughly enough. This prospective case-control study evaluated angiographic and clinical outcomes of PTCA alone and a combination of excimer laser coronary angioplasty (ELCA) and adjunct PTCA in 125 patients with ISR. ELCA was performed before balloon dilation in 67 patients, PTCA alone was performed in 58 patients. Basic demographic and clinical data were comparable in both groups. Lesions included in ELCA group were longer (17.1+/-9.9 vs 13.6+/-9.1 mm; p = 0.034), more complex (36.5% type C stenoses vs 14.3%; p = 0.006), and more frequently had reduced distal blood flow (TIMI <3: 18.9% vs 4.8%; p = 0.025) compared to lesions in the PTCA group. Immediate angiographic results of PTCA and ELCA + PTCA appeared to be comparable. PTCA alone was successful in 57 patients (98.3%), ELCA + PTCA, in 66 patients (98.5%). The rates of hospital complications were comparable (3.0% in ELCA group vs 8.6% in PTCA group). The 1-year follow-up showed that the rates of major adverse cardiac events (MACE) were comparable in the 2 groups (37.3% in ELCA group vs 46.6% in PTCA group). The rates of target vessel revascularization (TVR) within 1 year after the intervention were also similar in the 2 groups (32.8% vs 34.5%). The data mean that ELCA in patients with complex ISR is efficient and safe. Despite a higher complexity of lesions in the ELCA group, no increase in the rate of complications was registered.  相似文献   
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8.
The incidence of aneurysms of the pulmonary artery is known to be very low. Although diagnosis and evaluation of pulmonary artery aneurysms may be difficult without angiography, computed tomography and MRI's have emerged as useful noninvasive techniques. However, a transthoracic echocardiogram may reveal a pulmonary artery aneurysm. To our knowledge, transesophageal echocardiographic findings of pulmonary artery aneurysm with thrombus have not been reported in detail. Here, a case of thrombosed aneurysm of the main pulmonary artery diagnosed by transesophageal echocardiography and confirmed by computed tomography and MRI is reported.  相似文献   
9.
A 20-year-old pregnant woman was admitted to our department with symptoms of deep venous thrombosis in the left lower extremity and excessive lumbar pain. Low-molecular-weight heparin was administered. She recovered with this treatement, however, severe lumbar pain continued. A lumbar magnetic resonance imageg showed dilated epidural veins compressing the roots and acute thrombosis of the inferior vena cava extending to renal veins. During the same period she had acute deep venous thrombosis in her right leg. An urgent venous thrombectomy was performed. Sciatica and deep venous thrombosis resolved after the operation. Low-molecular-weight heparin was administered until the end of her pregnancy.  相似文献   
10.
An 18-year-old female patient suffering from a painful right-sided neck mass was admitted to our emergency service. Computed tomography of the neck revealed thrombosis of the right internal jugular vein. Computed tomography of the chest indicated septic pulmonary emboli in both lungs. Blood and oropharyngeal cultures showed proteus that was sensitive to cefepime and amicasin. Chemotherapy was administered for 12 days, however, her complaints continued with fulminant progression. An urgent decompression and excessive debridement were performed. Although Lemierre syndrome is a well-known cause of internal jugular vein thrombosis, association with proteus culture is very rare.  相似文献   
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