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981.
982.
建立了生物组织中胺甲硫磷和甲基毒死蜱的反相高效液相色谱分析方法。选用YWG-C18H375mm(内径)×200mm柱作为分析柱,流动相选用80∶20(V/V)的甲醇/水二元体系,流速为1.0ml/min,检测波长胺甲硫磷为252nm,甲基毒死蜱为290nm。该方法简单、快速、准确。其最小检出量为2.5×10-8g,最小检出浓度为0.25mg/L。  相似文献   
983.
目的:探讨慢性胰腺炎K-ras基因突变的临床病理学意义。方法:9例手术切除的慢性胰腺炎的石蜡标本,用微解剖法分离慢性胰腺炎的胰导管上皮粘液细胞增生灶,提取,扩增DNA,用ASO斑点杂交检测K-ras基因第12密码子的碱基序列。对9例接受手术治疗的病人进行长期随访,结果:9例慢性胰腺炎中4例有明显的胰导管上皮粘液细胞增生,其中2例被检出GAT型突变,分别占全组和有胰管上皮粘液细胞增生的22%和505,两个突变病例分别是接受了胰体尾切除和胰头十二指肠切除手术,术后分别随访17年和10年,没有发现任何恶变迹象,结构:慢性胰腺为可以检出K-ras基因突变,发生了K-ras基因突变的慢性胰腺炎上皮粘液细胞增生灶,未必一定发生为胰腺癌,胰液、粪便、末梢血液和尿液的检测,以及胰腺组织细针刺液检出K-ras基因突变,对胰腺癌的诊断有重要参考价值,但不应视为胰腺癌的确诊依据。  相似文献   
984.
目的:通过A/J系小鼠肺腺癌模型,探讨肺肿瘤细胞的起源和恶性转化过程。方法:应用4-氮喹啉1-氧化物(4QO)化学物质为促癌剂,建立A/J系列小鼠肺癌的模型。观察诱发肿瘤时间、肿瘤数目及与类型的关系。结果:RNQO诱发5个月时,共发现肺肿瘤17处,其中肺泡上皮增生(AP)6处。肺泡腺瘤(AA)9处,乳头状腺瘤(PA)2处;诱发7个月时共发现肺肿瘤19处,AP为7处,AA为11处,PA为1处,诱发9个月时共发现肺肿瘤27处,AP为5处,AA为17处,PA为3处,发现乳头状腺癌(PC)2处。结论:4NQO能诱发A/J系小鼠肺腺癌。诱发肿瘤的时间长短与发生肿瘤的组织学类型有密切关系。  相似文献   
985.
人脑星形细胞瘤PTEN基因的突变   总被引:1,自引:1,他引:0  
目的 探讨phosphatase and tensin homolog deleted on chromosome ten (PTEN)基因突变在人星形细胞瘤发生和恶性进展中的作用。方法 应用聚合酶链反应-单链构象多态性结合银染技术检测星形细胞瘤PTEN基因第5外显子区域的突变情况。结果 10例正常脑组织和10例良性脑膜瘤均无点突变发生,62例星形细胞瘤中7例(11.29%)有点突变发生,并且点突变发生与星形细胞瘤病理分级明显相关(P<0.05),其中高恶性度星形细胞瘤(Ⅲ-Ⅳ级)突变率(18.91%)明显高于低恶性度(Ⅰ-Ⅱ级)星形细胞瘤(P<0.05)。结论 PTEN基因突变与星形细胞瘤病理分级关系密切,属于星形细胞瘤恶性进展的后期事件。  相似文献   
986.
[目的]对比研究常规X线、二维CT和三维CT对颌骨肿瘤显示的优缺点。[方法]对51例颌骨肿瘤患者行常规X线、二维CT和三维CT检查,比较分析三种检查方法对颌骨肿瘤晃示的特征,并与手术病理结果相对照。[结果]对下颌骨肿瘤三种检查方法均能有交地显示,以三维CT显示得最为直观明了。对上颌骨肿瘤,三维CT通过旋转与切割,能够立体直观地显示肿瘤的部位、大小、形状及毗邻关系,尤其对腭板、眶下壁以及颅底骨质破坏的显示更具成越性;二维CT对肿瘤的囊性或实性改变、肿瘤的软组织成份以及颅内受侵情况的显示最为有利;常规X线对肿瘤区牙根周围的改变显示得最为清楚。[结论]常规X线、二维CT和三维CT对颌骨肿瘤的显示各有优缺点,三者结合能提高肿瘤显示的准确性,对颌骨肿瘤的诊断和治疗具有重要作用。  相似文献   
987.
In this paper, we study fractional‐order optimal control problems (FOCPs) involving the Atangana‐Baleanu fractional derivative. A computational method based on B‐spline polynomials and their operational matrix of Atangana‐Baleanu fractional integration is proposed for the numerical solution of this class of problems. With this numerical technique, the FOCPs are reduced to a system of equations which are solved for the unknown parameters with the help of Mathematica® software. Our results show the applicability and usefulness of the numerical technique.  相似文献   
988.
International Urology and Nephrology - A systemic inflammation response index (SIRI) has been recently introduced as a tool for the assessment of the prognosis of several critical medical...  相似文献   
989.
BackgroundHyperinsulinemia and inflammation are inter-related pathways that link diet with the risk of several chronic diseases. Evidence suggests that these pathways may also increase prostate cancer risk.ObjectiveTo determine whether hyperinsulinemic diet and inflammatory diet are associated with prostate cancer incidence and mortality.Design, setting, and participantsWe prospectively followed 41 209 men in the Health Professionals Follow-up Study (1986–2014). Scores for two validated dietary patterns were calculated from food frequency questionnaires at baseline and updated every 4 yr.Outcome measurements and statistical analysisTotal, advanced, and lethal prostate cancer outcomes were assessed. Multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were determined for associations between two empirical hypothesis-oriented dietary patterns—empirical dietary index for hyperinsulinemia and empirical dietary inflammatory pattern—and prostate cancer risk estimated using Cox proportional hazard regression.Results and limitationsDuring 28 yr of follow-up, 5929 incident cases of total prostate cancer, including 1019 advanced and 667 fatal, were documented. In multivariable-adjusted models, there was a 7% higher risk of advanced prostate cancer (HR: 1.07; 95% CI: 1.01–1.15) and a 9% higher risk of fatal prostate cancer (HR: 1.09; 95% CI: 1.00–1.18) per standard deviation (SD) increase in the hyperinsulinemic diet. When stratified by age, the hyperinsulinemic diet was associated with only earlier-onset aggressive prostate cancer (men under 65 yr), with per SD HRs of 1.20 (95% CI: 1.06–1.35) for advanced, 1.22 (1.04–1.42) for fatal, and 1.20 (1.04–1.38) for lethal. The inflammatory diet was not associated with prostate cancer risk in the overall study population, but was associated with earlier-onset lethal prostate cancer (per SD increase HR: 1.16; 95% CI: 1.00–1.35).ConclusionsHyperinsulinemia and inflammation may be potential mechanisms linking dietary patterns with the risk of aggressive prostate cancer, particularly earlier-onset disease.Patient summaryAvoiding inflammatory and hyperinsulinemic dietary patterns may be beneficial for the prevention of clinically relevant prostate cancer, especially among younger men.  相似文献   
990.
Wang  Jue  Wu  Jiang  Xu  Minghuo  Gao  Quanwen  Chen  Baoguo  Wang  Fang  Niu  Hao  Song  Huifeng 《Lasers in medical science》2021,36(6):1275-1282

The focus of treatment of faciocervical scar contractures includes cervical reconstruction and elimination of hypertrophic scars. Unfortunately, most previous studies have neglected the esthetic appearance of scars. In this study, we tried to combine surgical therapy and ultrapulse fractional CO2 laser (UFCL) to eliminate facial scars while restoring neck reconstruction and to establish the optimal conventional management for faciocervical contracture. Thirty-eight individuals were enrolled and divided into two groups. After received cervical release surgeries, comprehensive UFCL therapy group received treatment of UFCL at 3-month intervals, silicone sheets, and pressure garments, while another group only received treatment of silicone sheeting and compression. Twelve months after the termination of therapy, faciocervical scars of both two groups were assessed by two uninvolved physicians according to the Vancouver Scar Scale (VSS), and patients’ satisfaction survey was also recorded by the study participants using a patient four-point satisfaction scale. Thirty-six patients completed the treatment and follow-up. The results show that the VSS scores of both two groups decreased after 12 months, but comprehensive UFCL therapy group dropped more significantly than the conventional treatment group at follow-up session, which was statistically significant (P?<?0.001), and the patient satisfaction was higher than that of the conventional treatment group. This comprehensive treatment combined of surgery, UFCL, silicone sheets, and pressure garments works as an effective and esthetic reconstruction for moderate to severe postburn faciocervical scar contractures.

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