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991.
Squamous cell carcinoma of the pancreas is an unusual cancer of ductal cell origin. In a review of 6668 cases of exocrine pancreatic cancer from various registries reported from 1950 through 1985, the incidence of squamous carcinoma and adenosquamous carcinoma was 0.005% and 0.01%, respectively) We report a case of squamous cell carcinoma of the pancreas with liver metastasis.  相似文献   
992.
The aim of this study was to analyse the resistance and epidemiological data of 117 Acinetobacter baumannii isolates from Southwest Hospital, Chongqing, China. Except for polymyxin B, tigecycline, minocycline, cefoperazone/sulbactam, amikacin and levofloxacin, the resistance rates of other antimicrobial agents were above 90%. All the clinical isolates had the blaOXA-51 gene and 114 isolates had the blaOXA-23 gene. Forty-nine isolates were found to contain the blaIMP-4 gene. PFGE data showed that 117 isolates were divided into 25 groups. Sixty-three (53.85%) were found to carry the class 1 integron, and the sequence analysis of the class 1 integron internal variable regions – five types, one of which had the blaIMP-4 gene. For the blaIMP-4 positive strain without class 1 integron, we found the flanking sequence had the TnpA gene. The result suggested that the resistance gene was widely distributed in our hospital; moreover, the modes of presence and transmission are different and complicated. The results of our study can improve the infection empirical treatment method and infection control programme.  相似文献   
993.

Purpose

No biomarker is available for pancreatic cancer early detection, but a small prospective European study involving 16 cases and 32 controls raised the possibility that anti-Ezrin autoantibodies may be associated with risk of pancreatic cancer. We aimed to validate this finding in a case–control study nested within a prospective study in the USA.

Methods

Levels of anti-Ezrin autoantibodies were examined using ELISA in pre-diagnostic plasma samples of 73 cases and 145 matched controls. Paired t test and paired signed rank tests were used to determine the difference between two groups, and conditional logistic regression was used to evaluate the association between anti-Ezrin autoantibody levels and risk of developing pancreatic cancer.

Results

No association was found between levels of anti-Ezrin plasma autoantibodies and subsequent risk of developing pancreatic cancer.

Conclusion

Anti-Ezrin autoantibodies did not appear to be useful as a plasma biomarker for early detection of pancreatic cancer.
  相似文献   
994.
995.
乳腺超声弹性成像检查的影响因素及解决策略   总被引:5,自引:1,他引:4  
超声弹性成像(UE)是近年来应用于乳腺疾病诊断的一种新技术,在乳腺良恶性肿瘤的鉴别诊断中已显示出良好的应用前景。为提高UE对乳腺病变诊断的准确性,必须正确认识UE原理,掌握正确的检查方法,避免或减少主观因素造成误诊;进一步研究UE表现的相应病理基础;以超声特征诊断乳腺恶性病变的Logistic回归模型有助于鉴别乳腺良、恶性病变。对于超声检查不典型的乳腺病灶仍有必要行穿刺活检以明确诊断。  相似文献   
996.
Jiang YM  Long LL  Zhu XY  Zheng H  Fu X  Ou SY  Wei DL  Zhou HL  Zheng W 《Toxicology letters》2008,181(2):118-125
Environmental and occupational exposure to lead (Pb) remains to be a major public health issue. The purpose of this cross-sectional study was to use non-invasive magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy ((1)H MRS) techniques to investigate whether chronic exposure to Pb in an occupational setting altered brain structure and function of Pb-exposed workers. The Pb-exposed group consisted of 15 workers recruited from either a Pb-smelting factory or a Pb-battery manufacturer. The control group had 19 healthy volunteers who had no history of Pb exposure in working environment or at home. The average airborne Pb concentrations in fume and dust were 0.43 and 0.44mg/m(3), respectively, in the smeltery, and 0.10 and 1.06mg/m(3), respectively, in the Pb battery workshop. The average blood Pb concentrations (BPb) in Pb-exposed and control workers were 63.5 and 8.7mug/dL, respectively. The MRI examination showed that brain hippocampal volume among Pb-exposed workers was significantly diminished in comparison to age-matched control subjects (p<0.01), although the extent of this reduction was relatively small (5-6% of the control values). Linear regression analyses revealed significant inverse associations between BPb and the decreased hippocampal volume on both sides of brain hemisphere. Among five brain metabolites investigated by MRS, i.e., N-acetyl-aspartate (NAA), creatine (Cr), choline (Cho), inosine (mI), glutamate/glutamine (Glx) and lipids (Lip), a significant decrease in NAA/Cr ratio (7% of controls, p<0.05) and a remarkable increase in Lip/Cr ratio (40%, p<0.01) were observed in the brains of Pb-exposed workers as compared to controls. Furthermore, the increased Lip/Cr ratio was significantly associated with BPb (r=0.46, p<0.01). Taken together, this study suggests that occupational exposure to Pb may cause subtle structural and functional alteration in human brains. The MRI and MRS brain imaging techniques can be used as the non-invasive means to evaluate Pb-induced neurotoxicity.  相似文献   
997.
目的 采用气相色谱法(GC)结合气相色谱-质谱(GC-MS)联用技术,对3种不同来源共26批鱼肝油样品中的脂肪酸成分进行测定。方法 通过氢氧化钾-甲醇碱催化法对鱼肝油样品进行甲基衍生化预处理,选用极性毛细管柱对样品中的衍生化产物脂肪酸甲酯进行分离,后经气相色谱仪-氢火焰离子化检测器(GC-FID)和气相色谱-质谱(GC-MS)联用仪进行分析检测。利用对照品定位法结合NIST谱库检索准确鉴定出棕榈酸、棕榈油酸、油酸、亚油酸、二十碳五烯酸(eicosapentaenoic acid,EPA)和二十二碳六烯酸(docosahexaenoic acid,DHA)等14种脂肪酸,并通过面积归一化法对这14种脂肪酸进行定量分析。结果 这14种脂肪酸在国内鱼肝油中的含量与模拟天然鱼肝油和进口鱼肝油样品中的含量存在较大差异。其中,EPA和DHA等脂肪酸在模拟天然鱼肝油和进口鱼肝油样品中的含量远高于其在国内鱼肝油样品中的含量,而亚油酸在国内鱼肝油样品中的含量却高达44%以上,10倍于其在另外2种鱼肝油样品中的含量。结论 不同来源的鱼肝油样品中的脂肪酸成分不尽相同,可根据脂肪酸的组成区别鱼肝油样品中是否添加天然鱼肝油成分。  相似文献   
998.
目的:通过系统检索中英文医学期刊发表的中医药干预中风的临床随机对照试验,分析年度证据产出情况。方法:CNKI、Sino Med、维普、万方、Cochrane library、Pub Med、Embase、Web of Science等数据库,检索时限为2018年1月1日至2018年12月31日。收集中医药干预中风的临床随机对照试验。对全年发文概况、期刊分布、省份和单位分布、疾病类型、干预措施、结局指标以及干预疗程等内容进行描述性分析。结果:2018年发表的中医药干预中风的RCT共有1 084篇研究中,近90%研究重点是缺血性中风;近70%的研究采用的干预措施是中药方剂,剂型主要是汤剂;共涉及69个口服中成药和18个中药注射剂。干预疗程以2和4周为主,占64. 91%,疗程≤6个月的研究占98. 32%。神经功能、运动功能、生活能力以及生命质量评价为研究关注的结局指标。结论:中医药干预中风研究年度发文较多,但干预措施较为分散,干预疗程显著不足,研究设计存在较多问题。建议整合区域研究力量,围绕重点问题进行协同攻关,提高研究质量,减少研究浪费。  相似文献   
999.
“健康中国”战略对我国慢性病管理模式的发展提出了更高要求。通过文献资料及逻辑分析等研究方法,对我国慢性病管理模式的价值意蕴、慢性病管理的典型模式及慢性病管理存在的问题等方面进行审视,探索“健康中国”背景下我国慢性病管理模式发展的优化路径。研究认为,我国慢性病管理存在慢性病防治健康教育力度不足、专业医务人员数量紧缺、慢性病管理信息平台建设不平衡及慢性病管理体系不健全等突出问题。基于此,结合“健康中国”战略的发展要求,提出优化路径:行稳致远——提高居民健康教育的力度,强基固本——推进基层医疗卫生队伍的建设,互联互通——加快慢性病管理信息平台的开发,统筹兼顾——搭建慢性病管理的分级诊疗体系。  相似文献   
1000.
The purpose of this study was to investigate the feasibility of inducing ocular ischemic syndrome in spontaneously hypertensive rats. Hypertensive and normotensive Wistar–Kyoto rats had bilateral occlusion or sham surgery. They were divided into 4 groups: (1) hypertensive‐ischemia, (2) hypertensive‐sham, (3) normotensive‐ischemia, and (4) normotensive‐sham. Four months after the operation, the global changes of the eye and pupillary light reflex were assessed. Then each rat was perfused, and randomly one of the bulbuses oculi was prepared as retinal flat mounts for investigation of vascular changes. The opposite eyeball was prepared as a paraffin section for observation of the linear density of retinal ganglion cells and for thickness measurement. One hypertensive‐ischemia rat had a cataract in one eye and another rat in the same group had bulbus oculi collapse in one eye. The light reflex disappeared in 13.33% of hypertensive‐ischemia rats, and the rest of the hypertensive‐ischemia rats and normotensive‐ischemia rats had slow reflex. Compared with the respective controls, the peripheral retinal vascular network in hypertensive‐ischemia and normotensive‐ischemia rats was sparse; linear density of the retinal ganglion cells was significantly reduced; and the retinal thickness was reduced. Compared with normotensive‐ischemia rats, the hypertensive‐ischemia rats demonstrated more severe changes. After bilateral common carotic artery occlusion, the eyes of hypertensive rats developed various pathological changes similar to those of ocular ischemic syndrome. In conclusion, an animal model for ocular ischemic syndrome can be created by bilateral common carotid artery occlusion in spontaneously hypertensive rats. Anat Rec, 299:806–814, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
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