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991.
992.
Background: There is an increased evidence of an association between inflammatory mediators, particularly serum IL-6, depression and cognitive impairment in the elderly. This study aims at exploring the relation of peripheral IL-6 to cognitive functions in elderly patients with major depressive disorder (MDD).

Objectives: (1) Assessment of serum IL-6 levels and cognitive functions in elderly patients suffering from major depression and comparing them to healthy age-matched control subjects; (2) correlation between serum IL-6 levels and clinical characteristics of depression and cognitive functions in these patients.

Subjects and methods: The study is an observational, case-control study. It consisted of 80 subjects, 40 with the diagnosis of MDD according to the Diagnostic and Statistical Manual of Mental Disorders (DSM IV-TR) with early onset (first episode before the age of 60) and 40 community-dwelling subjects. They were subjected to the Structured Clinical Interview according to DSM-IV, Montreal Cognitive Assessment, Montgomery Asberg Depression Rating Scale, and serum IL-6 assay using ELISA.

Results: In the depression group, subjects had lower scores in cognitive testing, than the control group (p = 0.001). Serum IL-6 was found to have a negative correlation with cognitive testing in these patients even after controlling for the severity of depressive status and Body Mass Index (BMI) (p = 0.025).

Conclusions: MDD in elderly subjects is associated with decline in cognitive functions that may be related to peripheral IL-6 levels.  相似文献   

993.
Human epidermal growth factor receptor 2 (HER2) is expressed by the majority of human osteosarcomas and is a risk factor for poor outcome. Unlike breast cancer, osteosarcoma cells express HER2 at too low, a level for patients to benefit from HER2 monoclonal antibodies. We reasoned that this limitation might be overcome by genetically modifying T cells with HER2-specific chimeric antigen receptors (CARs), because even a low frequency of receptor engagement could be sufficient to induce effector cell killing of the tumor. HER2-specific T cells were generated by retroviral transduction with a HER2-specific CAR containing a CD28.ζ signaling domain. HER2-specific T cells recognized HER2-positive osteosarcoma cells as judged by their ability to proliferate, produce immunostimulatory T helper 1 cytokines, and kill HER2-positive osteosarcoma cell lines in vitro. The adoptive transfer of HER2-specific T cells caused regression of established osteosarcoma xenografts in locoregional as well as metastatic mouse models. In contrast, delivery of nontransduced (NT) T cells did not change the tumor growth pattern. Genetic modification of T cells with CARs specific for target antigens, expressed at too low a level to be effectively recognized by monoclonal antibodies, may allow immunotherapy to be more broadly applicable for human cancer therapy.  相似文献   
994.
995.
This work investigates the feasibility of using friction stir welding (FSW) process as a groove filling welding technique to weld duplex stainless steel (DSS) that is extensively used by petroleum service companies and marine industries. For the FSW experiments, three different groove geometries without root gap were designed and machined in a DSS plates 6.5 mm thick. FSW were carried out to produce butt-joints at a constant tool rotation rate of 300 rpm, traverse welding speed of 25 mm/min, and tilt angle of 3o using tungsten carbide (WC) tool. For comparison, the same DSS plates were welded using gas tungsten arc welding (GTAW). The produced joints were evaluated and characterized using radiographic inspection, optical microscopy, and hardness and tensile testing. Electron back scattering diffraction (EBSD) was used to examine the grain structure and phases before and after FSW. The initial results indicate that FSW were used successfully to weld DSS joints with different groove designs with defect-free joints produced using the 60° V-shape groove with a 2 mm root face without root gap. This friction stir welded (FSWed) joint was further investigated and compared with the GTAW joint. The FSWed joint microstructure mainly consists of α and γ with significant grain refining; the GTWA weld contains different austenitic-phase (γ) morphologies such as grain boundary austenite (GBA), intragranular austenite precipitates (IGA), and Widmanstätten austenite (WA) besides the ferrite phase (α) in the weld zone (WZ) due to the used high heat input and 2209 filler rod. The yield strength, ultimate tensile strength, and elongation of the FSWed joint are enhanced over the GTAW weldment by 21%, 41%, and 66% and over the BM by 65%, 33%, and 54%, respectively. EBSD investigation showed a significant grain refining after FSW with grain size average of 1.88 µm for austenite and 2.2 µm for ferrite.  相似文献   
996.
997.
Objective.  This study aims to translate and evaluate the performance of a Chinese version of the Child Oral Health-related Quality of Life (COHQoL©) measure composed of the Child Perception Questionnaire (CPQ), Parental Perception Questionnaire (PPQ), and Family Impact Scale (FIS).
Basic research design.  Chinese versions of the measures were derived through a forward–backward translation. A consecutive sample of 168 children attending paediatric dental and orthodontic clinics in Hong Kong were recruited along with their attending primary caregiver. Children self-completed the 37-item CPQ and their attending primary caregiver self-completed the 31-item PPQ and 14-item FIS consecutively and independently. Reassessments were conducted prior to their next appointment.
Results.  CPQ, PPQ, and FIS scores were associated with children's global rating of oral health ( P  < 0.05) and oral well-being ( P  < 0.05) supporting their construct validity. In addition, variations in CPQ, PPQ, and FIS were apparent with respect to patient group ( P  < 0.05) supporting their ability to distinguish between patient groups. Cronbach alpha values (internal reliability) and intraclass correlation coefficient values (test–retest reliability) for the three measures were > 0.80.
Conclusion.  A Chinese version of the three components of the COHQoL measure was developed with minor modifications. In psychometric testing, the validity of the three components was supported and they demonstrated acceptable reliability.  相似文献   
998.
999.

Objective

To evaluate the accuracy of CESM technique in predicting the final pathological response and residual tumor size post NAC in LABC.

Patients and methods

This study was prospectively carried on 21 female patients diagnosed with stage II and III breast cancer. CESM was done at the end of last cycle of chemotherapy and before definitive surgery.

Results

The sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), false negative and false positive of the CESM were assessed by comparing the enhancement of the residual lesions and their size post neoadjuvant chemotherapy (NAC) with the final pathological response and residual tumor size in the MD Anderson system. The specificity of the CESM in predicting the tumor response to NAC in this initial study is 91%, sensitivity was 40% and the NPV and PPV were 80% and 62.5% respectively. The sensitivity of this technique for complete response detection was 100% with a specificity 83% and lowered sensitivity in detecting chemoresistant tumors (33.3%).

Conclusion

CESM is an emerging easy technique that can predict the final pathologic tumor response after NAC especially complete response acting as a good negative technique.  相似文献   
1000.
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