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31.
Immune defenses provide resistance against infectious disease that is critical to survival. But immune defenses are costly, and limited resources allocated to immunity are not available for other physiological or developmental processes. We propose a framework for explaining variation in patterns of investment in two important subsystems of anti-pathogen defense: innate (non-specific) and acquired (specific) immunity. The developmental costs of acquired immunity are high, but the costs of maintenance and activation are relatively low. Innate immunity imposes lower upfront developmental costs, but higher operating costs. Innate defenses are mobilized quickly and are effective against novel pathogens. Acquired responses are less effective against novel exposures, but more effective against secondary exposures due to immunological memory. Based on their distinct profiles of costs and effectiveness, we propose that the balance of investment in innate versus acquired immunity is variable, and that this balance is optimized in response to local ecological conditions early in development. Nutritional abundance, high pathogen exposure and low signals of extrinsic mortality risk during sensitive periods of immune development should all favor relatively higher levels of investment in acquired immunity. Undernutrition, low pathogen exposure, and high mortality risk should favor innate immune defenses. The hypothesis provides a framework for organizing prior empirical research on the impact of developmental environments on innate and acquired immunity, and suggests promising directions for future research in human ecological immunology.  相似文献   
32.
Vascular-related gene polymorphism can affect the susceptibility of coronary heart disease. In current study, we aimed to evaluate the contribution of four vascular-related gene CpG-SNPs to coronary heart disease (CHD). A total of 784 angiography-proven CHD patients and 746 non-CHD controls were included in the current association study. The four CpG-SNPs (including VEGFA rs1005230, ACE rs4316, CST3 rs3827143 and AGTR1 rs275653) were genotyped using the Sequenom MassARRAY platform. All genotype distribution of four SNPs met HWE. Among the four CpG-SNPs, none was found to be associated with CHD on both genotype and allele levels. Further subgroup tests by age or gender were unable to observe any significant associations of them with CHD. Our case-control study showed that none of four CpG-SNPs in the vascular-related genes was associated with the risk of CHD in Han Chinese, although we could not exclude other genetic variants of these vascular-related genes with contribution to CHD.  相似文献   
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目的:探究替米沙坦对冠心病合并糖尿病肾病患者疗效的影响情况。方法:56例探究目标对象均为某院接收的冠心病合并糖尿病肾病患者,挑选时间2018年6月~2019年6月。将"计算机表法"作为分组的参考,分配为参照组(n=28例)执行依那普利治疗,探究组(n=28例)执行替米沙坦治疗。结果:探究组的LVEF、LVEDd、肌酐、24h尿蛋白4项指标与参照组相比,差异有统计学意义(P<0.05);收缩压、舒张压、空腹血糖、餐后2h血糖4项指标与参照组相比,差异没有统计学意义(P>0.05)。结论:冠心病合并糖尿病肾病患者选择替米沙坦治疗后,心室功能的重构以及肾脏预后结局均得到改善,且临床效果比依那普利好,值得借鉴。  相似文献   
36.
Abstract

Background

Comorbidities are commonly seen in patients with coronavirus disease 2019 (COVID-19), but the clinical implication is not yet well-delineated. We aim to characterize the prevalence and clinical implications of comorbidities in patients with COVID-19.  相似文献   
37.
目的 观察参麦注射液治疗冠心痛的临床效果.方法 选取我院2013年4月-2014年1月间收治的冠心病患者94例,依据治疗方案不同分为治疗组48例,对照组46例,2组患者入院均根据病情给予能量合剂、血管扩张剂、减轻心脏负荷药物,并进行对症、溶栓及抗心律失常等常规治疗,治疗组患者在常规治疗的基础上给予参麦注射液静滴治疗,1次/d,用药2周为1疗程;于治疗2疗程后观察治疗效果,并对比2组患者临床症状、心电图改善情况及红细胞超氧化物歧化酶(E-SOD)平均活性,血浆过氧化脂质(P-LPO)、红细胞过氧化脂质(E-LPO)含量变化.结果 治疗组治疗后总有效率显著高于对照组(P<0.05);治疗组胸闷、心悸、心绞痛及ST段下移、T渡低平或倒置患者改善率显著均高于对照组(P<0.05);治疗组治疗后E-SOD活性显著高于对照组,P-LPO、E-LPO含量显著低于对照组(P<0.05).结论 参麦注射液可有效缓解冠心病患者临床症状,降低血中脂质过氧化物浓度,缓解心肌缺血状态.  相似文献   
38.
This article explores the spatio-temporal logics at work in global health. Influenced by ideas of time–space compression, the global health literature argues that the world is characterised by a convergence of disease patterns and biomedical knowledge. While not denying the influence of these temporalities and spatialities of globalisation within the global health and chronic disease field, the article argues that they sit alongside other, often-conflicting notions of time and space. To do so, it explores the spatio-temporal logics that underpin a highly influential epidemiological model of the smoking epidemic. Unlike the temporalities and spatialities of sameness described in much of the global health literature, the article shows that this model is articulated around temporalities and spatialities of difference. This is not the difference celebrated by postmoderns, but the difference of modernisation theorists built around nations, sequential stages and progress. Indeed, the model, in stark contrast to the ‘one world, one time, one health’ globalisation mantra, divides the world into nation–states and orders them along epidemiological, geographical and development lines.  相似文献   
39.
Idiopathic myointimal hyperplasia of mesenteric veins (IMHMV) is a rare and poorly understood ischemic colitis that occurs in the rectosigmoid colon of predominantly young, previously healthy, male patients. A 76‐year‐old Japanese man presented to our hospital with a 1‐year history of worsening diarrhea, lower abdominal pain, and weight loss (−6 kg). Laboratory evaluation revealed white blood cell count of 13 200/μL, C‐reactive protein level of 2.0 mg/dL (normal range, 0.0–0.3), and negative results for stool culture (including Clostridium difficile). Colonoscopy showed circumferential and edematous narrowing of the sigmoid colon with deep longitude ulceration. Biopsy was done and examination of the specimen demonstrated no specific ischemia. The patient was treated with bowel rest, antibiotics, and i.v. fluids; however, his symptoms worsened. Finally, sigmoidectomy was carried out. Histological examination demonstrated significant myointimal hyperplasia of mesenteric veins leading to thickening and stenosis of the venous lumen. Therefore, the final diagnosis was IMHMV. Three months following sigmoidectomy, he was asymptomatic.  相似文献   
40.
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