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1.
目的对治疗前原发性骶尾部脊索瘤(PSC)CT图像分型,并分析其CT征象,为诊断和个性化治疗提供依据。方法回顾性分析101例PSC患者治疗前的CT图像,包括肿瘤的部位、范围、大小、密度、肿瘤与邻近结构的关系。按照肿瘤的部位由上及下分为Ⅰ~Ⅳ型,并根据肿瘤侵犯的范围从小到大分为a^d亚型。采用Kruskal-Wallis H检验比较PSC各亚型的占比,并对各亚型之间进行两两比较。采用R×C列联表精确概率检验比较分型和亚型肿瘤钙化的发生率。采用单因素方差分析及LSD-t检验对各分型和亚型肿瘤的大小和密度进行分析、比较。结果101例PSC中,Ⅰ~Ⅳ型的发生率分别为17.8%、30.7%、36.6%、14.9%,a^d亚型的占比分别为9.9%、25.7%、58.4%、5.9%。各亚型的占比差异具有统计学意义(P=0.012)。c亚型明显高于a亚型(P=0.039),d亚型明显低于a亚型(P=0.036),其余各型之间无明显差异。各分型肿瘤内钙化的差异无统计学意义(P=0.233);各亚型肿瘤内钙化的差异有统计学意义(P=0.003),a^d亚型肿瘤钙化的比率逐渐增加。Ⅰ型肿瘤的左右径及上下径明显大于Ⅱ~Ⅳ型(P<0.05)。a亚型与b亚型肿瘤之间前后径的差异无统计学意义(P=0.102),b^d亚型之间前后径的差异均有统计学意义(P<0.05);不同亚型肿瘤之间的左右径、上下径之间的差异均有统计学意义(P<0.05),a亚型径线最小,d亚型径线最大。结论101例PSC中,Ⅱ、Ⅲ型最多见,肿瘤较少累及第一骶骨;各亚型中,a型较少见,c亚型最多见,d亚型最少见。肿瘤的密度与分型无关,肿瘤内钙化与亚型有关。Ⅰ型肿瘤侵犯的范围较Ⅱ~Ⅳ型广泛,a^d亚型肿瘤的径线逐渐增大,CT分型有利于判断肿瘤的范围。PSC诊断延迟现象比较明显,但很少发生远处侵犯和转移。CT图像可对治疗前PSC分型,为诊断和个性化治疗提供依据。  相似文献   
2.
ResearchGate is a world wide web for scientists and researchers to share papers, ask and answer questions, and find collaborators. As one of the more than 15 million members, the author uploads research output and reads and responds to some of the questions raised, which are related to type 2 diabetes. In that way, he noticed a serious gap of knowledge of this disease among medical professionals over recent decades. The main aim of the current study is to remedy this situation through providing a comprehensive review on recent developments in biochemistry and molecular biology, which can be helpful for the scientific understanding of the molecular nature of type 2 diabetes. To fill up the shortcomings in the curricula of medical education, and to familiarize the medical community with a new concept of the onset of type 2 diabetes, items are discussed like: Insulin resistance, glucose effectiveness, insulin sensitivity, cell membranes, membrane flexibility, unsaturation index (UI; number of carbon-carbon double bonds per 100 acyl chains of membrane phospholipids), slow-down principle, effects of temperature acclimation on phospholipid membrane composition, free fatty acids, energy transport, onset of type 2 diabetes, metformin, and exercise. Based on the reviewed data, a new model is presented with proposed steps in the development of type 2 diabetes, a disease arising as a result of a hypothetical hereditary anomaly, which causes hyperthermia in and around the mitochondria. Hyperthermia is counterbalanced by the slow-down principle, which lowers the amount of carbon-carbon double bonds of membrane phospholipid acyl chains. The accompanying reduction in the UI lowers membrane flexibility, promotes a redistribution of the lateral pressure in cell membranes, and thereby reduces the glucose transporter protein pore diameter of the transmembrane glucose transport channel of all Class I GLUT proteins. These events will set up a reduction in transmembrane glucose transport. So, a new blood glucose regulation system, effective in type 2 diabetes and its prediabetic phase, is based on variations in the acyl composition of phospholipids and operates independent of changes in insulin and glucose concentration. UI assessment is currently arising as a promising analytical technology for a membrane flexibility analysis. An increase in mitochondrial heat production plays a pivotal role in the existence of this regulation system.  相似文献   
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4.
Autoimmune thyroid diseases (AITD) and Type 1 diabetes (T1D) frequently occur in the same individual pointing to a strong shared genetic susceptibility. Indeed, the co-occurrence of T1D and AITD in the same individual is classified as a variant of the autoimmune polyglandular syndrome type 3 (designated APS3v). Our aim was to identify new genes and mechanisms causing the co-occurrence of T1D + AITD (APS3v) in the same individual using a genome-wide approach. For our discovery set we analyzed 346 Caucasian APS3v patients and 727 gender and ethnicity matched healthy controls. Genotyping was performed using the Illumina Human660W-Quad.v1. The replication set included 185 APS3v patients and 340 controls. Association analyses were performed using the PLINK program, and pathway analyses were performed using the MAGENTA software. We identified multiple signals within the HLA region and conditioning studies suggested that a few of them contributed independently to the strong association of the HLA locus with APS3v. Outside the HLA region, variants in GPR103, a gene not suggested by previous studies of APS3v, T1D, or AITD, showed genome-wide significance (p < 5 × 10−8). In addition, a locus on 1p13 containing the PTPN22 gene showed genome-wide significant associations. Pathway analysis demonstrated that cell cycle, B-cell development, CD40, and CTLA-4 signaling were the major pathways contributing to the pathogenesis of APS3v. These findings suggest that complex mechanisms involving T-cell and B-cell pathways are involved in the strong genetic association between AITD and T1D.  相似文献   
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6.
Caveolin-1 (Cav-1) appears to be both a pathophysiological contributor and a target in different inflammatory and hyperproliferative skin conditions as well as in skin aging. Skin fibroblasts demonstrate an up-regulation of Cav-1 expression both in chronological and UV-induced aging, and such an up-regulation was observed both in vitro and in vivo. Typical alterations in aging skin involve a reduction of the dermis thickness, a significant expansion of the dermal white adipose tissue as well as modifications of the content and distribution of hyaluronan, impairment of autophagic flux, a reduction of collagen expression and an increase in tissue inflammation. All of these phenomena can be connected with changes in Cav-1 expression in the aging skin. Modified expression of Cav-1 can also significantly influence the mechanical properties of individual skin layers, thus changing the total mechanical stability of the layered composite skin/WAT, leading to typical structural modifications of the skin surface in the aging skin. Selective reduction of Cav-1 expression has the potential to exert anti-aging effects on the skin.  相似文献   
7.
Bacterial keratitis continues to be one of the leading causes of corneal blindness in the developed as well as the developing world, despite swift progress since the dawn of the “anti-biotic era”. Although, we have expeditiously developed our understanding about the different causative organisms and associated pathology leading to keratitis, extensive gaps in knowledge continue to dampen the efforts required for early and accurate diagnosis, and management in these patients, resulting in poor clinical outcomes. The ability of the causative bacteria to subdue the therapeutic challenge stems from their large genome encoding complex regulatory networks, variety of unique virulence factors, and rapid secretion of tissue damaging proteases and toxins.In this review article, we provide an overview of the established diagnostic techniques and therapeutics for keratitis caused by various bacteria. We extensively report the recent in-roads through novel tools for accurately diagnosing mono- and poly-bacterial corneal infections. Furthermore, we outline the recent progress by our groups and others in understanding the sub-cellular genomic changes that lead to antibiotic resistance in these organisms. Finally, we discuss in detail, the novel therapies and drug delivery systems in development for the efficacious management of bacterial keratitis.  相似文献   
8.
Background and aimsDespite using sensor-augmented pump therapy (SAPT) with predictive low-glucose management (PLGM), hypoglycemia is still an issue in patients with type 1 Diabetes (T1D). Our aim was to determine factors associated with clinically significant hypoglycemia (<54 mg/dl) in persons with T1D treated with PLGM-SAPT.Methodology: This is a multicentric prospective real-life study performed in Colombia, Chile and Spain. Patients with T1D treated with PLGM-SAPT, using sensor ≥70% of time, were included. Data regarding pump and sensor use patterns and carbohydrate intake from 28 consecutive days were collected. A bivariate and multivariate Poisson regression analysis was carried out, to evaluate the association between the number of events of <54 mg/dl with the clinical variables and patterns of sensor and pump use.Results188 subjects were included (41 ± 13.8 years-old, 23 ± 12 years disease duration, A1c 7.2% ± 0.9). The median of events <54 mg/dl was four events/patient/month (IQR 1–10), 77% of these events occurred during day time. Multivariate analysis showed that the number of events of hypoglycemia were higher in patients with previous severe hypoglycemia (IRR1.38; 95% CI 1.19–1.61; p < 0.001), high glycemic variability defined as Coefficient of Variation (CV%) > 36% (IRR 2.09; 95%CI 1.79–2.45; p < 0.001) and hypoglycemia unawareness. A protector effect was identified for adequate sensor calibration (IRR 0.77; 95%CI 0.66–0.90; p:0.001), and the use of bolus wizard >60% (IRR 0.74; 95%CI 0.58–0.95; p:0.017).ConclusionIn spite of using advanced SAPT, clinically significant hypoglycemia is still a non-negligible risk. Only the identification and intervention of modifiable factors could help to prevent and reduce hypoglycemia in clinical practice.  相似文献   
9.
张金连    苑东敏  崔静  赵园园  王云云  杨帆  孙健平     《现代预防医学》2020,(8):1514-1518
目的 探讨血清谷丙转氨酶(ALT)与新诊2型糖尿病(T2DM)患病风险之间的关联,为T2DM的防治提供科学依据。方法 采用4阶段分层随机抽样的方法选取2006年和2009年参与青岛糖尿病预防项目的研究对象男性3 012例、女性4 422例,采用Pearson相关检验分析不同性别ALT与FPG、2 h PG的相关性,并利用多因素logistic回归分析ALT与新诊T2DM患病的关系。结果 男性中,ALT与空腹血浆血糖(FPG)、餐后2 h血浆血糖(2 h PG)的Pearson相关系数分别为0.088、0.080(均P<0.01);多因素logistic回归显示,在调整了年龄、BMI、糖尿病家族史、城乡、教育、婚姻、收入、吸烟及饮酒状况等混杂因素后,ALT的第4分位(Q4)组新诊T2DM患病风险是第1分位(Q1)组的1.832倍(OR = 1.832,95% CI:1.324~2.534,P<0.01)。女性中,ALT与FPG、2h PG的Pearson相关系数分别为0.065、0.108(均P<0.01);多因素logistic回归显示,在调整了年龄、BMI、糖尿病家族史、城乡、教育、婚姻、收入、吸烟及饮酒状况等混杂因素后,ALT的第4分位(Q4)组新诊T2DM患病风险是第1分位(Q1)组的1.445倍(OR = 1.445,95% CI:1.087~1.919,P<0.05)。结论 在男、女性人群中,ALT水平升高与T2DM患病相关,且这种相关性不受年龄、BMI、糖尿病家族史等的影响。  相似文献   
10.
目的:探讨玉液汤对2型糖尿病肥胖患者肠道菌群及脂质代谢影响。方法:选取2017年2月至2019年2月广州市中医医院收治的2型糖尿病肥胖患者106例作为研究对象,按照就诊顺序分为对照组和观察组,每组53例。2组均给予基础治疗+药物治疗,观察组再加用玉液汤治疗。观察2组治疗前、完成治疗后肠道菌群、脂质代谢、中医症状积分、血糖相关指标、体质量、腰围、体质量指数(BMI)变化并比较。结果:2组治疗前各指标比较差异无统计学意义(P>0.05),完成治疗后观察组患者的中医症状积分、FINS、HOMA-IR、HbAlc、BMI、腰围、体质量、TC、TG、LDL-C、肠杆菌、酵母菌、肠球菌、畏寒肢冷、腰膝酸软、脘腹2组患者治疗后HDL-C、双岐杆菌、乳杆菌、拟杆菌均较治疗后明显上升,且观察组高于对照组(P<0.05)。结论:玉液汤能改善2型糖尿病肥胖患者脂质代谢和临床症状,降低血糖,能调节肠道菌群紊乱,从而提高疗效。  相似文献   
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