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991.
992.
Advanced glycation end products (AGEs) are an important mediator in osteoarthritis (OA) and cause apoptosis in articular chondrocytes. Mitochondrial function is involved in modulating apoptosis of articular chondrocytes. This study was performed to investigate the mechanism of AGEs‐induced chondrocyte apoptosis. The ratio of apoptotic cell and cell viability was surveyed by TUNEL, MTT,LDH release assay. The reactive oxygen species was determined by the fluorescent probe 2’, 7’‐dichlorofluorescein diacetate. The expression of caspase‐3 and cytochrome c was detected by Western blot. The mitochondrial membrane potential (?Ψm) was evaluated by rhodamine‐123 fluorescence. We found that AGEs induced apoptosis in primary rabbit chondrocytes, upregulation of ROS production, cytochrome c, and caspase‐3 levels. Simultaneously, AGEs decreases the levels of ?Ψm and ATP production; however, the antibody of AGEs (sRAGE) and antioxidant‐N‐acetylcys‐teine (NAC) significantly reversed AGEs‐induced the above damage thus to protect the cells from apoptosis. These observations suggested that the mechanism of AGEs‐induced chondrocyte apoptosis was primarily via ROS production and mitochondria‐mediated caspase‐3 activation.  相似文献   
993.
994.
Despite having normal hearing sensitivity, patients with chronic tinnitus may experience more difficulty recognizing speech in adverse listening conditions as compared to controls. However, the association between the characteristics of tinnitus (severity and loudness) and speech recognition remains unclear. In this study, the Quick Speech-in-Noise test (QuickSIN) was conducted monaurally on 14 patients with bilateral tinnitus and 14 age- and hearing-matched adults to determine the relation between tinnitus characteristics and speech understanding. Further, Tinnitus Handicap Inventory (THI), tinnitus loudness magnitude estimation, and loudness matching were obtained to better characterize the perceptual and psychological aspects of tinnitus. The patients reported low THI scores, with most participants in the slight handicap category. Significant between-group differences in speech-in-noise performance were only found at the 5-dB signal-to-noise ratio (SNR) condition. The tinnitus group performed significantly worse in the left ear than in the right ear, even though bilateral tinnitus percept and symmetrical thresholds were reported in all patients. This between-ear difference is likely influenced by a right-ear advantage for speech sounds, as factors related to testing order and fatigue were ruled out. Additionally, significant correlations found between SNR loss in the left ear and tinnitus loudness matching suggest that perceptual factors related to tinnitus had an effect on speech-in-noise performance, pointing to a possible interaction between peripheral and cognitive factors in chronic tinnitus. Further studies, that take into account both hearing and cognitive abilities of patients, are needed to better parse out the effect of tinnitus in the absence of hearing impairment.  相似文献   
995.
目的:探讨卵巢囊性病变蒂扭转的MSCT表现与诊断价值。方法:回顾分析10例经手术病理证实的卵巢囊性病变蒂扭转的CT资料。结果:10例CT平扫均出现盆腔内囊实性双肿块,实性肿块与一侧子宫角或输卵管相连;囊壁均匀或不均匀增厚,合并囊内出血2例;卵巢明显肿大2例;6例子宫偏向扭转侧;2例合并腹盆腔积液,其中1例为血性渗液。结论:卵巢囊性病变蒂扭转的CT表现具有一定特征性,MSCT扫描作为超声检查的一种补充检查方法,对卵巢囊性病变蒂扭转的诊断及鉴别诊断具有重要的临床价值。  相似文献   
996.
目的分析原发眼眶淋巴瘤患者的放疗效果及不良反应。方法回顾性分析2006年3月至2012年8月就诊于天津市人民医院、天津市第一中心医院、天津市大港油田医院的28例原发眼眶淋巴瘤患者的临床资料。所有患者均行眶内肿物活组织检查或切除术,术后接受放疗,3例于放疗前行CHOP方案化疗。放疗采用三维适形调强技术,3~5野,2~2.5Gy/次,每周5次,总剂量20~50Gy。其中30Gv18例,22Gy1例,25Gy1例,20Gy1例,28.8Gy1例,40Gy3例,42Gy1例,46Gy1例和50Gy1例。结果28例患者放疗后均获完全缓解,其中1例放疗4个月后局部复发,再次放疗后完全缓解;1例死于淋巴瘤肺浸润。放疗期间发生急性并发症有结膜炎(28例,100.0%)和角膜炎(1例,3.6%),远期并发症有眼干燥症(10例,35.7%)和视力下降(1例,3.6%)。结论放疗是原发眼眶淋巴瘤有效的治疗方法,多数患者对不良反应耐受良好。  相似文献   
997.
Exosomes participate in cancer progression and metastasis by transferring bioactive molecules between cancer and various cells in the local and distant microenvironments. Such intercellular cross‐talk results in changes in multiple cellular and biological functions in recipient cells. Several hallmarks of cancer have reportedly been impacted by this exosome‐mediated cell‐to‐cell communication, including modulating immune responses, reprogramming stromal cells, remodeling the architecture of the extracellular matrix, or even endowing cancer cells with characteristics of drug resistance. Selectively, loading specific oncogenic molecules into exosomes highlights exosomes as potential diagnostic biomarkers as well as therapeutic targets. In addition, exosome‐based drug delivery strategies in preclinical and clinical trials have been shown to dramatically decrease cancer development. In the present review, we summarize the significant aspects of exosomes in cancer development that can provide novel strategies for potential clinical applications.  相似文献   
998.

Purpose

Target delineation in nasopharyngeal carcinoma (NPC) often proves challenging because of the notoriously narrow therapeutic margin. High doses are needed to achieve optimal levels of tumour control, and dosimetric inadequacy remains one of the most important independent factors affecting treatment outcome.

Method

A review of the available literature addressing the natural behaviour of NPC and correlation between clinical and pathological aspects of the disease was conducted. Existing international guidelines as well as published protocols specified by clinical trials on contouring of clinical target volumes (CTV) were compared. This information was then summarized into a preliminary draft guideline which was then circulated to international experts in the field for exchange of opinions and subsequent voting on areas with the greatest controversies.

Results

Common areas of uncertainty and variation in practices among experts experienced in radiation therapy for NPC were elucidated. Iterative revisions were made based on extensive discussion and final voting on controversial areas by the expert panel, to formulate the recommendations on contouring of CTV based on optimal geometric expansion and anatomical editing for those structures with substantial risk of microscopic infiltration.

Conclusion

Through this comprehensive review of available evidence and best practices at major institutions, as well as interactive exchange of vast experience by international experts, this set of consensus guidelines has been developed to provide a practical reference for appropriate contouring to ensure optimal target coverage. However, the final decision on the treatment volumes should be based on full consideration of individual patients’ factors and facilities of an individual centre (including the quality of imaging methods and the precision of treatment delivery).  相似文献   
999.

Background

In this analysis we compared quality-adjusted survival outcomes between nab-paclitaxel (nab-P) and standard paclitaxel (Pac) using data from the nab-P phase III registration trial in metastatic breast cancer.

Patients and Methods

Quality-adjusted overall survival was estimated using the quality-adjusted time without symptoms or toxicity (Q-TWiST) approach. Overall survival was partitioned into time without progression/Grade ≥ 3 adverse events (AEs) toxicity (TWiST), time with Grade ≥ 3 AE toxicity (TOX), and time after relapse (REL). Q-TWiST was calculated by multiplying mean time in each health state by its assigned utility (base-case utility values: time without symptoms of disease progression or toxicity of Grade ≥ 3 adverse events [TWiST] = 1.0, TOX = 0.5, and REL = 0.5). In threshold analyses, TOX and REL varied from 0.0 to 1.0 whereas TWiST was maintained at 1.0. Comparisons were made for the intent-to-treat population and the subset of patients initiating the study drugs as second or subsequent lines (2L+) of chemotherapy (per approved nab-P indication; 2L+ subpopulation). A ≥ 15% relative Q-TWiST gain (vs. mean Pac overall survival) was considered clearly clinically important.

Results

In the intent-to-treat population, nab-P (n = 229) versus Pac (n = 225) resulted in nonsignificant gains of 1.4 months of mean Q-TWiST (11.6 vs. 10.2 months; 95% confidence interval [CI], ?0.03 to 2.8). In the 2L+ subpopulation, nab-P (n = 132) versus Pac (n = 136) resulted in a statistically significant gain of 2.2 months of mean Q-TWiST (10.5 vs. 8.4 months; 95% CI, 0.6-3.8), with a 17.1% relative Q-TWiST gain (threshold analysis range, 14.0%-19.5%, both figures significant).

Conclusion

In its approved indication for metastatic breast cancer, nab-P showed a statistically significant and clearly clinically important improvement in quality-adjusted survival time versus Pac in the 2L+ subpopulation.  相似文献   
1000.
The art, craft and science of surgery is a highly interpersonal skill, central to a variety of traditions and cultures throughout human history. The development of surgery parallels the evolution of the human race from prehistory to the present time. This review attempts to examine the changing concepts and practices in surgery from the earliest era, enshrouded in mysticism and magic, through a manual craft performed by barbers and artisans, to a dignified profession based on science and technology. The evolution of surgery in the previous millennia is reviewed against the culture and morals, the politics and religion, and the philosophy and science of its period; in so doing assessing its perspective on the threshold of a new millennium.   相似文献   
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