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81.
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   

82.
In the past decade, the clinico-pathologic characteristics of neuroendocrine tumors (NETs) in the pancreas have been further elucidated. Previously termed “islet cell tumors/carcinomas” or “endocrine neoplasms”, they are now called pancreatic NETs (PanNETs). They occur in relatively younger patients and may arise anywhere in the pancreas. Some are associated with von Hippel–Lindau, MEN1, and other syndromes. It is now widely recognized that, with the exception of tumorlets (minute incipient neoplasms) that occur in some syndromes like MEN1, all PanNETs are malignant, albeit low-grade, and although they have a protracted clinical course and overall 10-year survival of 60–70 %, even low-stage and low-grade examples may recur and/or metastasize on long-term follow-up. Per recent consensus guidelines adopted by both European and North American NET Societies (ENETS and NANETs) and WHO-2010, PanNETs are now graded and staged separately, unlike previous classification schemes that used a combination of grade, stage, and adjunct prognosticators in an attempt to define “benign behavior” or “malignant” categories. For staging, the ENETs proposal may be more applicable than CAP/AJCC, which is based on the staging of exocrine tumors. Current grading of PanNETs is based on mitotic activity and ki-67 index. Other promising prognosticators such as necrosis, CK19, c-kit, and others are still under investigation. It has also been recognized that PanNETs have a rather wide morphologic repertoire including oncocytic, pleomorphic, ductulo-insular, sclerosing, and lipid-rich variants. Most PanNETs are diagnosed by fine needle aspiration biopsy, in which single, monotonous plasmacytoid cells with fair amounts of cytoplasm and distinctive neuroendocrine chromatin are diagnostic. Molecular alterations of PanNETs are also very different than that of ductal or acinar tumors. Loss of expression of DAXX and ATRX proteins has been recently identified in 45 %. Along with these improvements, several controversies remain, including grading, value of current cutoff ranges, and the best methods for counting ki-67 index (manual count by computer-captured image may be the most practical for the time being). More important is the controversial use of the term “carcinoma”, which was previously employed in WHO-2004 only for invasive and metastatic cases but has now been made synonymous with grade 3 group of tumors. It is becoming clear that grade 3 group comprises two distinct categories: (1) differentiated but proliferatively more active tumors which typically have ki-67 indices in the 20–50 % range and (2) true poorly differentiated NE carcinomas as defined in the lung, with ki-67 typically >50 %. Further studies are needed to address these controversial aspects of PanNETs.  相似文献   
83.

Background

In sepsis, risk assessment is as crucial as early and accurate diagnosis. In this study, we aimed to evaluate the prognostic value of mid-regional proadrenomedullin (MR-proADM) with other scoring systems in severe sepsis and septic shock patients due to community acquired pneumonia (CAP).

Methods

Patients were divided into 2 groups as severe sepsis and septic shock due to CAP (group 1, n=31) and only CAP group (group 2, n=26). Serum MR-proADM, procalcitonin (PCT), C-reactive protein (CRP), and d-dimer level were analyzed. Acute Physiological and Chronic Health Evaluation (APACHE) II score, Sequential Organ Failure Assessment (SOFA) score, and Pneumonia Severity Index (PSI) were performed for all patients.

Results

There was no difference between groups in terms of serum MR-proADM levels (P=0.780). Serum MR-proADM was not found a significant value for the prediction of death within the 4 and 8 weeks in all patients. SOFA score was the most significant to predict mortality in 4 and 8 weeks (P<0.001). The combination of SOFA score and serum MR-proADM was a strong factor to predict death in 4 weeks (specifity 86.8% and sensitivity 66.7%). The combination of MR-proADM, SOFA score, and APACHE II score was found 75.0% sensitive and 71.4% specific to predict mortality within 4 weeks in group 1.

Conclusions

The MR-proADM does not correlate with mortality or disease severity to predict mortality. The combination of SOFA, APACHE II scores, and MR-proADM was efficient to predict prognosis and mortality rate in severe sepsis or septic shock patients.  相似文献   
84.
The aim of the study was to investigate the validity and reliability of the Turkish version of the fatigue severity scale (FSS) in fibromyalgia (FM) patients. Sixty-one FM patients and 54 healthy controls were evaluated using the Turkish version of the FSS. Reliability was investigated using test–retest reliability and internal consistency. Concurrent validity was evaluated between the FSS score and the VAS fatigue. Convergent validity was assessed by comparing the FSS score with the scores of VAS pain, Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), and Fibromyalgia Impact Questionnaire (FIQ). Spearman’s rank correlation coefficient was used to evaluate validity. Test–retest reliability and internal consistency of the FSS were excellent in FM patients (ICC: 0.94, Cronbach’s alpha coefficient: 0.85) and in the healthy controls (ICC: 0.90, Cronbach’s alpha coefficient: 0.91). For the concurrent validity, the correlation between the FSS and VAS fatigue was very good in FM group (r: 0.63, P: 0.000) and in the healthy controls (r: 0.94, P: 0.000). For the convergent validity, correlations between the FSS and BDI, BAI, FIQ, pain intensity were moderate to good in both groups (P: 0.000). The Turkish version of the FSS has been proved to be valid and reliable to detect severity of fatigue in FM patients. We recommend the use of it in clinical practice.  相似文献   
85.
Sarcoidosis is a chronic, multisystemic, non-caseating granulomatous disease of unknown etiology. Nasopharyngeal involvement is very rare in sarcoidosis. The objective of this report was to evaluate a rare involvement of sarcoidosis. This report includes a case of nasopharyngeal sarcoidosis. A 51-year-old female with nasopharyngeal sarcoidosis was treated as sarcoidosis, and she was better. Nasopharyngeal involvement is very rare in sarcoidosis but it must be kept in mind.  相似文献   
86.
Introduction and Objective: The present study aims to quantitatively evaluate the right ventricle (RV) function by means of transthoracic echocardiography in normal children and childhood congenital heart disease patients with pulmonary hypertension. Patients and Methods: This study was conducted in a cohort including 40 healthy children and 30 pediatric patients with pulmonary hypertension who were diagnosed under close surveillance at the study center between October 2009 and November 2010. Results: Statistically significant differences were found between the patient and control groups for the right ventricle myocardial performance index (RVMPI), the left ventricle myocardial performance index (LVMPI), the tricuspid valve systolic flow velocity (Ts), the ratio of systolic pulmonary artery pressure to the right ventricle outflow tract systolic flow velocity time integral (sPAP/RVOT VTI), and the ratio of systolic pulmonary artery pressure to right ventricle outflow tract systolic flow velocity time integral × heart rate (sPAP/[RVOT VTI×HR]). When the children were divided into three groups based on their pulmonary vascular resistance significant differences emerged that predicted an increasing severity of RV dysfunction. Significant differences were also observed for the RVMPI, the LVMPI, and the Ts as well as for echocardiographic pulmonary flow (Qp) and systemic flow (Qs). Discussion: The present study demonstrates that echocardiographic parameters can be used for the quantitative detection of RV dysfunction in childhood congenital heart disease patients with high pulmonary artery pressure (systolic, diastolic, and mean) or pulmonary vascular resistance.  相似文献   
87.
88.

Introduction

The primary goal of this study was to compare the chest wall thicknesses (CWT) at the 2nd intercostal space (ICS) at the mid-clavicular line (MCL) and 5th ICS at the mid-axillary line (MAL) in a population of patients with a CT confirmed pneumothorax (PTX). This result will help physicians to determine the optimum needle thoracostomy (NT) puncture site in patients with a PTX.

Materials and methods

All trauma patients who presented consecutively to A&E over a 12-month period were included. Among all the trauma patients with a chest CT (4204 patients), 160 were included in the final analysis. CWTs were measured at both sides and were compared in all subgroup of patients.

Results

The average CWT for men on the 2nd ICS-MCL was 38 mm and for women was 52 mm; on the other hand, on the 5th ICS-MAL was 33 mm for men and 38 mm for women. On the 2nd ICS-MCL 17% of men and 48% of women; on the 5th ICS-MAL 13% of men and 33% of women would be inaccessible with a routine 5-cm catheter. Patients with trauma, subcutaneous emphysema and multiple rib fractures would have thicker CWT on the 2nd ICS-MCL. Patients with trauma, lung contusion, sternum fracture, subcutaneous emphysema and multiple rib fractures would have thicker CWT on the 5th ICS-MAL.

Conclusions

This study confirms that a 5.0-cm catheter would be unlikely to access the pleural space in at least 1/3 of female and 1/10 of male Turkish trauma patients, regardless of the puncture site. If NT is needed, the 5th ICS-MAL is a better option for a puncture site with thinner CWT.  相似文献   
89.
Predictors of aortic dilatation are not well described in patients with bicuspid aortic valves (BAV). This study sought to examine the relationship between proximal aortic dilatation and matrix metalloproteinase-9 (MMP-9) and alpha 1-antitrypsin (α1AT) levels in patients with BAV. All patients underwent echocardiography using a standard protocol, and aortic measurements were taken in end-diastole. We studied 82 patients with BAV and categorized them into two groups according to aortic dimensions corrected for body surface area and age. The plasma level of α1AT was routinely determined using a BN ProSpec analyzer (Siemens Healthcare Diagnostics, Marburg, Germany), and that of MMP-9 were determined by ELISA (RayBiotech Inc. Norcross, GA, USA). Statistical analysis was performed using the Statistical Package for Social Sciences (SPSS; SPSS Inc., Chicago, IL, USA) software for Windows version 12. This study included patients with BAV with no or mild valvular impairment. There were no significant differences between groups in terms of gender, body surface area, associated hypertension, diabetes mellitus, hyperlipidemia, or smoking. The mean ascending aortic diameter was 4.38?±?0.5?mm in group 1 and 3.34?±?0.35?mm in group 2 (p?相似文献   
90.
Hearing loss has commonly been reported in association with thyroid disorders and during treatment with propylthiouracil. The relationship between hyperthyroidism and the auditory system has not been previously investigated. The aim of this cross-sectional, case-control study was to investigate hearing loss in patients with Graves' disease (GD). The study population consisted of patients with newly diagnosed GD and healthy controls. Pure tone audiometry at frequencies of 250, 500, 1000, 2000, 4000 and 8000 Hz, along with immittance measures including tympanometry and acoustic reflex tests, were performed in all participants. Twenty-two GD patients and 22 healthy controls consented to inclusion in the study. The differences between groups with regards to age and gender distribution were statistically insignificant (P = 0.567 and P = 0.757, respectively). The hearing thresholds of right and left ears were also similar in both groups (P > 0.05). When single-ear evaluations were taken into account (total of 44 ears for both groups), hearing thresholds in the GD group were significantly higher than healthy controls at all frequencies (P < 0.05). Following testing at the designated frequencies, the only significant effect of thyrotoxicosis was observed with frequencies of 4000 and 8000 Hz. The odds ratio for having hearing loss at a frequency of 8000 HZ associated with GD was 14.97 (95% confidence interval 4.03-55.64). In patients with GD, right and left pure tone audiometric findings at a frequency of 8000 Hz correlated positively with FT3, FT4 and negatively with TSH. Our results are highly suggestive of a decrease in hearing ability in patients with GD, particularly at high frequencies. Further studies are needed to help elucidate the mechanisms behind hearing loss which develops in association with GD.  相似文献   
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