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151.
Two new wide bandgap block copolymers (PL1 and PL2) with porphyrin‐incorporated side chains are designed and used as electron donors for solution‐processed bulk heterojunction polymer solar cells. The photophysical, electrochemical, and photovoltaic properties, charge transport mobility and film morphology of these two block copolymers are investigated. Detailed investigations reveal that the different alkyl groups and electron‐withdrawing substituents on the porphyrin pendant units have significant influence on the polymer solubility, absorption energy level, band gap, and charge separation in the bulk‐heterojunction thin films, and thus the overall photovoltaic performances. Organic photovoltaic devices derived from these copolymers and ([6,6]‐phenyl‐C71‐butyric acid methyl ester) (PC71BM) acceptor show the best power conversion efficiencies of 5.83% and 7.14%, respectively. These results show that the inclusion of a certain proportion of side chain porphyrin group as a pendant in the traditional donor‐acceptor (D‐A) type polymer can broaden the molecular absorption range and become a full‐color absorbing molecule. The size of the porphyrin pendant also has an obvious effect on the properties of the molecule.  相似文献   
152.
Background: The control and management of many oral health conditions highly depend on one's daily self‐care practice and compliance to preventive and curative measures. Conventional (health) education (CE), focusing on disseminating information and giving normative advice, is insufficient to achieve sustained behavioral changes. A counseling approach, motivational interviewing (MI), is potentially useful in changing oral health behaviors. This systematic review aims to synthesize the evidence on the effectiveness of MI compared with CE in improving oral health. Methods: Four databases (PubMed MEDLINE, Web of Science, Cochrane Library, and PsycINFO) were searched to identify randomized controlled trials that evaluated the effectiveness of MI compared with CE in changing oral health behaviors and improving oral health of dental patients and the public. The scientific quality of the studies was rated, and their key findings were qualitatively synthesized. Results: The search yielded 221 potentially relevant papers, among which 20 papers (on 16 studies) met the eligibility criteria. The quality of the studies varied from 10 to 18 out of a highest possible score of 21. Concerning periodontal health, superior effect of MI on oral hygiene was found in five trials and was absent in two trials. Two trials targeting smoking cessation in adolescents failed to generate a positive effect. MI outperformed CE in improving at least one outcome in four studies on preventing early childhood caries, one study on adherence to dental appointments, and two studies on abstinence of illicit drugs and alcohol use to prevent the reoccurrence of facial injury. Conclusions: Reviewed randomized controlled trials showed varied success of MI in improving oral health. The potential of MI in dental health care, especially on improving periodontal health, remains controversial. Additional studies with methodologic rigor are needed for a better understanding of the roles of MI in dental practice.  相似文献   
153.
Neonatal resuscitation is a coordinated, team-based series of timed sequential steps that focuses on a transitional physiology to improve perinatal and neonatal outcomes. The practice of neonatal resuscitation has evolved over time and continues to be shaped by emerging evidence as well as key opinions. We present the revised Neonatal Resuscitation Guidelines for Singapore 2021. The recommendations from the International Liaison Committee on Resuscitation Neonatal Task Force Consensus on Science and Treatment Recommendations (2020) and guidelines from the American Heart Association and European Resuscitation Council were compared with existing guidelines. The recommendations of the Neonatal Subgroup of the Singapore Resuscitation and First Aid Council were derived after the work group discussed and appraised the current available evidence and their applicability to local clinical practice.  相似文献   
154.
Purpose

This study was conducted to: (a) investigate the levels and progress of subjective recovery from recent-onset psychosis; (b) examine its predictive factors and; (c) describe perceived challenges and opportunities affecting recovery. The findings were expected to help inform recovery-oriented psychiatric care in low-income, particularly African, countries.

Methods

This sequential explanatory mixed-methods study involved 263 service users with recent-onset psychosis from Northwestern Ethiopia. For the quantitative part, a 9-month longitudinal study approach was employed with three time point measurements over 9 months. Predictor variables for subjective recovery from recent-onset psychosis were identified by hierarchical multiple linear regression tests. Following the quantitative survey, individual qualitative interviews were conducted with 19 participants. Interview data were transcribed and thematically analysed.

Results

High mean subjective recovery scores were recorded throughout the study (Questionnaire about the Process of Recovery score ranging from 44.17 to 44.65). Quality of life, internalized stigma, disability, hopelessness, satisfaction with social support, and central obesity were significant predictors of subjective recovery across the three time points. Participants’ perceived challenges and opportunities affecting their recovery were categorized into four themes.

Conclusion

In Ethiopia, a low percentage of individuals with SMIs initiate psychiatric treatment and many discontinue this to attend spiritual healing. In this study, the Ethiopian SMI patients engaged consistently in psychiatric treatment indicated high mean subjective recovery scores. Devising mechanisms to integrate the psychiatric treatment and spiritual healing sectors are suggested. Approaches to improve quality of life, functioning, hope, internalized stigma and provide need-based social support are suggested.

  相似文献   
155.
目的比较分析头部肿瘤两种固定技术的摆位误差,评估以光学表面监测系统(optical surface monitoring system,OSMS)为辅助手段引导摆位并进行监测的可行性。方法头部肿瘤患者A组26例采用发泡胶+头部热塑闭合面罩固定,B组20例采用发泡胶+头部热塑开口面罩固定+光学表面监测系统。A组摆位后进行锥形束CT( cone beam computed tomography, CBCT )扫描共178次,B组摆位经过OSMO调整后进行治疗前CBCT扫描162次,将获得的CBCT图像和计划CT图像匹配,得到X、Y、Z轴方向上的平移及旋转误差,并对摆位误差进行比较分析。通过OSMS调整摆位误差的标准为三维方向上平移误差≤ 1mm、旋转误差≤1°,调整后OSMS监测的摆位误差与治疗前CBCT 扫描配准摆位误差的差异定义为OSMS的精度。运用OSMS跟踪监测整个治疗过程中患者的实时摆位误差,并记录分次内的最大三维矢量误差、旋转误差及治疗时间。结果B组与A组分次间的三维矢量误差(1.73±0.90)mm/(2.24±1.25)mm,X、Z轴上的平移误差(0.04±1.00)mm/(-0.34±1.48)mm、(0.06±0.86)mm/(0.29±1.14)mm,X轴旋转角度误差(0.01±0.09)°/(0.18±0.95)°和平均摆位时间2.5 min/2.0 min,经比较差异具有统计学意义(P<0.05)。B组OSMS的精度在三维矢量误差为(1.28±0.74)mm。OSMS跟踪监测患者分次内的最大三维矢量误差(0.71±0.47)mm,旋转角度误差为(0.46±0.40)°。结论与常规的采用闭合面罩固定相比,采用开口面罩固定并应用OSMS辅助摆位,不仅可便捷有效地减小头部肿瘤患者的分次间摆位误差,而且能实时跟踪并监测分次内的摆位误差。  相似文献   
156.
Neural systems of second language reading are shaped by native language   总被引:22,自引:0,他引:22  
Reading in a second language (L2) is a complex task that entails an interaction between L2 and the native language (L1). To study the underlying mechanisms, we used functional magnetic resonance imaging (fMRI) to visualize Chinese-English bilinguals' brain activity in phonological processing of logographic Chinese and alphabetic English, two written languages with a sharp contrast in phonology and orthography. In Experiment 1, we found that phonological processing of Chinese characters recruits a neural system involving left middle frontal and posterior parietal gyri, cortical regions that are known to contribute to spatial information representation, spatial working memory, and coordination of cognitive resources as a central executive system. We assume that the peak activation of this system is relevant to the unique feature of Chinese that a logographic character has a square configuration that maps onto a monosyllabic unit of speech. Equally important, when our bilingual subjects performed a phonological task on English words, this neural system was most active, whereas brain areas mediating English monolinguals' fine-grained phonemic analysis, as demonstrated by Experiment 2, were only weakly activated. This suggests that our bilingual subjects were applying their L1 system to L2 reading and that the lack of letter-to-sound conversion rules in Chinese led Chinese readers to being less capable of processing English by recourse to an analytic reading system on which English monolinguals rely. Our brain imaging findings lend strongest support to the idea that language experience tunes the cortex.  相似文献   
157.
Present guidelines recommend a multidisciplinary team (MDT) approach to diabetic foot ulcer (DFU) care, but relevant data from Asia are lacking. We aim to evaluate the clinical and economic outcomes of an MDT approach in a lower extremity amputation prevention programme (LEAPP) for DFU care in an Asian population. We performed a case‐control study of 84 patients with DFU between January 2017 and October 2017 (retrospective control) vs 117 patients with DFU between December 2017 and July 2018 (prospective LEAPP cohort). Comparing the clinical outcomes between the retrospective cohort and the LEAPP cohort, there was a significant decrease in mean time from referral to index clinic visit (38.6 vs 9.5 days, P < .001), increase in outpatient podiatry follow‐up (33% vs 76%, P < .001), decrease in 1‐year minor amputation rate (14% vs 3%, P = .007), and decrease in 1‐year major amputation rate (9% vs 3%, P = .05). Simulation of cost avoidance demonstrated an annualised cost avoidance of USD $1.86m (SGD $2.5m) for patients within the LEAPP cohort. In conclusion, similar to the data from Western societies, an MDT approach in an Asian population, via a LEAPP for patients with DFU, demonstrated a significant reduction in minor and major amputation rates, with annualised cost avoidance of USD $1.86m.  相似文献   
158.
目的 研究胃腺癌组织中p53、E-cadherin的表达,分析它们和临床病理参数对预后的影响.方法 采用组织芯片和免疫组化检测150例胃腺癌中p53、E-cadherin的表达,分析它们和临床病理参数对预后的影响.单因素分析用Kaplan-Meier法计算累积生存率并比较患者术后平均生存时间,多因素分析用COX回归.结果 150例胃腺癌中p53阳性率为31.3%;E-cadherin阳性率为91.3%.随访到的74例胃腺癌患者1年生存率为83.8%,3年生存率为70.3%,5年生存率为63.5%.单因素分析年龄、分化程度、Laurén分类、浸润深度、淋巴结状况、pTNM分期是影响胃腺癌预后的因素;多因素分析p53、年龄、淋巴结状况为影响胃腺癌预后的独立因素(P<0.05).结论 p53、年龄、分化程度、Laurén分类、浸润深度、淋巴结状况和pTNM分期是影响胃腺癌预后的因素,而E-cadherin和组织学分类不是影响胃腺癌预后的因素.  相似文献   
159.
Major surgery is immunosuppressive, and this could have an impact on postoperative tumor immunosurveillance and, therefore, long-term survival in cancer patients. Video-assisted thoracic surgery (VATS) lung resection is a new alternative surgical approach to thoracotomy for patients with early lung cancer. This is a pilot study to examine the postoperative changes in leukocytes, lymphocyte subsets, B cells, T cells, and natural killer (NK) cells in non-small-cell lung cancer (NSCLC) patients undergoing lung resection with VATS versus thoracotomy approaches. Twenty-one consecutive patients with resectable primary NSCLC were assigned to VATS or thoracotomy approach over a 3-month period. Blood samples were collected preoperatively and at postoperative days (POD) 1, 3, and 7 for flow cytometry determination of total leucocytes, B cells, NK cells, lymphocytes, total T cells, and T4 and T8 cell numbers. There were no demographic differences between the two groups. Compared with the preoperative values, significantly increased total white cell numbers were detected at POD 1, 3, and 7 in all patients. At POD 1, although T8 cells and NK cells were reduced in both groups, total T cell, T4 cell, and lymphocyte numbers were significantly reduced only in the thoracotomy group. At POD 7, NK cell numbers were significantly lower in the thoracotomy group than that in the VATS group. No significant intra- or intergroup differences were seen with B cells. No significant differences in survival or disease-free survival were found between the two groups. Thus, VATS major lung resection for NSCLC is associated with less, as well as quicker recovery from, postoperative immunosuppression compared with the thoracotomy approach. The clinical relevance of better preserved cellular immunity in the early postoperative period warrants confirmation from large randomized trials.  相似文献   
160.
Objective: Although laparoscopic incisional hernioplasty has been gaining in popularity, the best approach for the repair of incisional hernia remains controversial. The present study was undertaken to evaluate the medium‐term outcomes of laparoscopic incisional hernioplasties utilizing onlay GORE‐TEX DualMesh (GORE‐TEX DualMesh Biomaterial; W.L. Gore and Associates, Flagstaff, Arizona, TX, USA). Methodology: Between June 2000 and July 2004, 42 patients underwent laparoscopic incisional hernioplasties at our institution. Perioperative data and postoperative outcomes were collected prospectively and analyzed. Results: Laparoscopic incisional hernioplasty was successfully performed on 39 (93%) patients. Conversion to open repair was required in three patients. The overall mean operative time was 108 min. Sixteen patients (37%) were found to have more than one hernial defect after reduction of the hernial contents. Postoperative morbidity included seroma (n = 8), urinary retention (n = 3), ileus (n = 1), pneumonia (n = 1), fever (n = 1), wound infection (n = 1), and prolonged suture site pain (n = 1) in 13 patients. All these morbidities resolved spontaneously without intervention. Two‐thirds of the patients were discharged within 2 days after surgery. With a median follow up of 2 years, two clinical recurrences (4.8%) were detected. Conclusion: Laparoscopic approach was a safe and efficacious technique for the repair of incisional hernia. Medium‐term outcomes were promising with low postoperative morbidity and recurrence rates. This technique allows clear identification of multiple hernial defects and confers the advantages of minimal access surgery.  相似文献   
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