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1.
为了解渐危植物新疆野核桃的病害情况,在新疆野核桃自然保护区调查不同坡向、不同龄级野核桃4种病害的患病比例,分析病害种类、病害等级与野核桃胸径及坡向的相关关系。结果表明: 保护区野核桃的主要病害为核桃褐斑病(95.8%)、核桃枯枝病(90.5%)、核桃黑斑病(74.4%)和核桃腐朽病(7.7%)。4个坡向的野核桃均易患核桃褐斑病,阴坡和半阴坡的野核桃易患核桃枯枝病,阳坡和阴坡的野核桃易患核桃黑斑病,半阳坡和半阴坡的野核桃相对易患核桃腐朽病。4个坡向野核桃的4种病害均随病害等级(1~4级)的增加而病株比例减小。4个坡向核桃枯枝病、核桃黑斑病、核桃褐斑病均以中龄树比例最大,其次是老龄树,再次是小树,未见幼苗患病;核桃腐朽病仅发生在老龄树。核桃枯枝病、核桃腐朽病、核桃黑斑病、核桃褐斑病与野核桃的胸径呈显著正相关,核桃黑斑病与坡向呈显著负相关,核桃枯枝病、核桃腐朽病、核桃黑斑病的不同病害等级与胸径和坡向存在相关性。  相似文献   

2.
我国蜜蜂主要病原检测技术   总被引:3,自引:0,他引:3  
颜珣  韩日畴 《昆虫知识》2008,45(3):483-488
蜜蜂是重要的经济昆虫。蜜蜂病害威胁蜜蜂产业的发展。蜜蜂病害检测及病原鉴定是病害防治的基础。文章详细介绍我国蜜蜂常见6种主要病害(美洲幼虫腐臭病,欧洲幼虫腐臭病,囊状幼虫病,慢性麻痹病,微孢子虫病,白垩病)的病原快速准确的检测方法。  相似文献   

3.
Vogt-Koyanagi-Harada (VKH) disease (and sympathetic ophthalmia) is an ocular inflammatory disease that is considered to be a cell-mediated autoimmune disease against melanocytes. The purpose of this study was to determine the Ags specific to VKH disease and to develop an animal model of VKH disease. We found that exposure of lymphocytes from patients with VKH disease to peptides (30-mer) derived from the tyrosinase family proteins led to significant proliferation of the lymphocytes. Immunization of these peptides into pigmented rats induced ocular and extraocular changes that highly resembled human VKH disease, and we suggest that an experimental VKH disease was induced in these rats. We conclude that VKH disease is an autoimmune disease against the tyrosinase family proteins.  相似文献   

4.
宠物的抗病育种研究具有重要的意义,本文对开展抗病育种的必要性、宠物免疫抗病系统、疾病抗性遗传机制、免疫反应的遗传控制、宠物抗病常规育种、宠物抗病分子育种以及抗病育种方法的现状、存在的问题、展望进行了介绍。说明了对疾病抗性的选择有一个坚实基础。抗病育种是控制疾病的有效方法,应用前景美好。  相似文献   

5.
Although Alzheimer's disease is considered to be a degenerative brain disease, it is clear that the immune system has an important role in the disease process. As discussed in this Review, immune-based therapies that are designed to remove amyloid-beta peptide from the brain have produced positive results in animal models of the disease and are being tested in humans with Alzheimer's disease. Although immunotherapy holds great promise for the treatment of Alzheimer's disease, clinical trials of active amyloid-beta vaccination of patients with Alzheimer's disease were discontinued after some patients developed meningoencephalitis. New immunotherapies using humoral and cell-based approaches are currently being investigated for the treatment and prevention of Alzheimer's disease.  相似文献   

6.
The increasing use of the common marmoset (Callithrix jacchus) in research makes it important to diagnose spontaneous disease that may confound experimental studies. Bone disease and gastrointestinal disease are two major causes of morbidity and mortality in captive marmosets, but currently no effective antemortem tests are available to identify affected animals prior to the terminal stage of disease. In this study we propose that bone disease and gastrointestinal disease are associated disease entities in marmosets and aim to establish the efficacy of several economical antemortem tests in identifying and predicting disease. Tissues from marmosets were examined to define affected animals and unaffected controls. Complete blood count, serum chemistry values, body weight, quantitative radiographs, and tissue-specific biochemical markers were evaluated as candidate biomarkers for disease. Bone and gastrointestinal disease were associated, with marmosets being over seven times more likely to have either concurrent bone and gastrointestinal disease or neither disease as opposed to lesions in only one organ system. When used in tandem, serum albumin <3.5 g/dL and body weight <325 g identified 100% of the marmosets affected with concurrent bone and gastrointestinal disease. Progressive body weight loss of 0.05% of peak body weight per day predicted which marmosets would develop disease prior to the terminal stage. Bone tissue-specific tests, such as quantitative analysis of radiographs and serum parathyroid hormone levels, were effective for distinguishing between marmosets with bone disease and those without. These results provide an avenue for making informed decisions regarding the removal of affected marmosets from studies in a timely manner, preserving the integrity of research results.  相似文献   

7.
Human disease states are commonly viewed in one of two ways. First, there is the clinical definition of disease as the presence or absence of a pathological condition. Second, there is the biologist's representation of disease as a point in a multivariate space of continuous physiological variables associated with suboptimal performance and survival. We present a model to represent dependency between multiple disease processes. The model is consistent with both concepts of disease and is designed to be estimated in the usual context of chronic disease information, i.e., a general lack of information about the time of disease incidence and progression. Consideration is made of the effects of individuals' differential susceptibility to disease and how these effects distinguish the disease incidence functions estimated at the individual level from those estimated for a population.  相似文献   

8.
摘要 目的:分析川崎病患儿肠道菌群构成及分布与其冠状动脉病变的相关性。方法:选择我院自2020年1月至2023年2月接诊的86例川崎病患儿作为研究对象,根据是否出现冠状动脉病变,分为冠状动脉病变组(35例)和非冠状动脉病变组(51例)。检测所有患儿的肠道菌群多样性[肠道菌群丰度(Ace指数)、肠道菌群多样性(Shannon指数)]、肠道菌群构成比例[门水平(变形菌门、厚壁菌门、拟杆菌门)、属水平(乳杆菌属、拟杆菌属、韦荣球菌属)],使用多因素Logistic回归分析肠道菌群构成及分布与冠状动脉病变的关系。结果:冠状动脉病变组Ace指数大于非冠状动脉病变组(P<0.05);冠状动脉病变组与非冠状动脉病变组的Shannon指数比较无差异(P>0.05);冠状动脉病变组肠道厚壁菌门占比低于非冠状动脉病变组,拟杆菌门占比高于非冠状动脉病变组(P<0.05);冠状动脉病变组与非冠状动脉病变组的肠道变形菌门占比比较无差异(P>0.05);冠状动脉病变组肠道乳杆菌属占比、韦荣球菌属占比均低于非冠状动脉病变组(P<0.05);冠状动脉病变组与非冠状动脉病变组的肠道拟杆菌属占比比较无差异(P>0.05);经多因素Logistic回归分析,肠道Ace指数、厚壁菌门、拟杆菌门、乳杆菌属、韦荣球菌属均是川崎病患儿发生冠状动脉病变的独立影响因素(P<0.05)。结论:川崎病患儿肠道菌群构成及分布与其冠状动脉病变密切相关,为改善肠道菌群失调、增加患儿的临床获益提供依据,应引起临床重视。  相似文献   

9.
Disease mapping models have been popularly used to model disease incidence with spatial correlation. In disease mapping models, zero inflation is an important issue, which often occurs in disease incidence datasets with high proportions of zero disease count. It is originated from limited survey coverage or unadvanced testing equipment, which makes some regions have no observed patients. Then excessive zeros recorded in the disease incidence dataset would mess up the true distributions of disease incidence and lead to inaccurate estimates. To address this issue, a zero-inflated disease mapping model is developed in this work. In this model, a zero-inflated process using Bernoulli indicators is assumed to characterize whether the zero inflation occurs for each region. For regions without zero inflation, a coherent and generative disease mapping model is applied for mapping the spatially correlated disease incidence. Independent spatial random effects are incorporated in both processes to account for the spatial patterns of zero inflation and disease incidence. External covariates are also considered in both processes to better explain the disease count data. To estimate the model, a Markov chain Monte Carlo algorithm is proposed. We evaluate model performance via a variety of simulation experiments. Finally, a Lyme disease dataset of Virginia is analyzed to illustrate the application of the proposed model.  相似文献   

10.
基于功能一致性利用蛋白质互作网络挖掘潜在的疾病致病基因,对于了解疾病致病机理和改进临床治疗至关重要.基于基因功能一致性和其在蛋白质互作网络中的拓扑属性将基因与疾病之间建立关联,对疾病风险位点内的基因进行了致病风险预测,并通过GO及KEGG功能富集分析方法进一步筛选,预测出新的致病基因.预测出了51个新的冠心病致病基因,分析发现大部分基因参与了冠心病的致病过程.为疾病基因的挖掘提出一个新的思路,从而有助于复杂疾病致病机理的研究.  相似文献   

11.
Shadrina MI  Slominskiĭ PA 《Genetika》2006,42(8):1045-1059
The current views on the role of genetic factors in the pathogenesis of Parkinson's disease are considered. The review is focused on monogenic forms of the disease, for which 11 loci are mapped and seven genes whose mutations cause the disease are identified. In addition, a number of candidate genes for sporadic Parkinson's disease are described. The further development of studying genetic bases of Parkinson's disease will follow two main directions: in-depth analysis of genes related to the monogenic form of the disease and more large-scale associative investigation of candidate genes for the sporadic form of Parkinson's disease.  相似文献   

12.
The current views on the role of genetic factors in the pathogenesis of Parkinson’s disease are considered. The review is focused on monogenic forms of the disease, for which 11 loci are mapped and seven genes whose mutations cause the disease are identified. In addition, a number of candidate genes for sporadic Parkinson’s disease are described. The further development of studying genetic bases of Parkinson’s disease will follow two main directions: in-depth analysis of genes related to the monogenic form of the disease and more large-scale associative investigation of candidate genes for the sporadic form of Parkinson’s disease.  相似文献   

13.
OBJECTIVE--To investigate a reported association between dental disease and risk of coronary heart disease. SETTING--National sample of American adults who participated in a health examination survey in the early 1970s. DESIGN--Prospective cohort study in which participants underwent a standard dental examination at baseline and were followed up to 1987. Proportional hazards analysis was used to estimate relative risks adjusted for several covariates. MAIN OUTCOME MEASURES--Incidence of mortality or admission to hospital because of coronary heart disease; total mortality. RESULTS--Among all 9760 subjects included in the analysis those with periodontitis had a 25% increased risk of coronary heart disease relative to those with minimal periodontal disease. Poor oral hygiene, determined by the extent of dental debris and calculus, was also associated with an increased incidence of coronary heart disease. In men younger than 50 years at baseline periodontal disease was a stronger risk factor for coronary heart disease; men with periodontitis had a relative risk of 1.72. Both periodontal disease and poor oral hygiene showed stronger associations with total mortality than with coronary heart disease. CONCLUSION--Dental disease is associated with an increased risk of coronary heart disease, particularly in young men. Whether this is a causal association is unclear. Dental health may be a more general indicator of personal hygiene and possibly health care practices.  相似文献   

14.
Maternal heart disease complicates at least 1% of pregnancies and is one of the most important causes of maternal death. In developing countries rheumatic heart disease remains the major cause of maternal heart disease, while in developed countries maternal congenital heart disease has become more prevalent due to the improved survival of children with congenital heart disease. In addition, the prevalence of coronary artery disease is rising because of unhealthy lifestyle and the tendency to postpone motherhood until the third decade.  相似文献   

15.
It is increasingly evident that human diseases are not isolated from each other. Understanding how different diseases are related to each other based on the underlying biology could provide new insights into disease etiology, classification, and shared biological mechanisms. We have taken a computational approach to studying disease relationships through 1) systematic identification of disease associated genes by literature mining, 2) associating diseases to biological pathways where disease genes are enriched, and 3) linking diseases together based on shared pathways. We identified 4,195 candidate disease associated genes for 1028 diseases. On average, about 50% of disease associated genes of a disease are statistically mapped to pathways. We generated a disease network which consists of 591 diseases and 6,931 disease relationships. We examined properties of this network and provided examples of novel disease relationships which cannot be readily captured through simple literature search or gene overlap analysis. Our results could potentially provide insights into the design of novel, pathway-guided therapeutic interventions for diseases.  相似文献   

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17.
A model describing disease progress of non-specialised fungal pathogens in intraspecific mixed stands of cereal cultivars (Jeger, Griffiths & Jones, 1981b) has been extended beyond the logarithmic phase of disease development. The extended. logistic model indicates that whatever the outcome in the early stages (disease less than or more than the mean of disease in the pure stands), disease will eventually level off at a value equal to the mean of disease asymptotes in the pure stands. The time scale involved in such levelling-off, however, means that substantial benefit may still be expected from deployment of such mixtures. Analytical solutions for the model are obtained for the special case where the ratio of disease asymptote to initial disease is the same for each pure stand.  相似文献   

18.
IgA nephropathy (IgAN) or Berger’s disease is a slowly progressing disease that leads to end-stage renal disease in 50 % of the patients within 25 years of the disease. However, several factors are associated with the accelerated progression of this disease causing early development of end-stage disease. Persistent proteinuria or hematuria, poorly controlled hypertension, elevated serum creatinine and prevalent glomerulosclerosis are some of the risk factors that expedite the deteriorative effects of IgAN. Thus, the progression of the disease can be delayed if the associated risk factors are handled and addressed in the nick of time.  相似文献   

19.
Investigation of the incidence of peste des petits ruminants (PPR) disease in goats revealed seasonality in the natural occurrence of PPR disease in the environment. Tissue culture rinderpest vaccine was shown effective in protecting goats against the disease. The optimal time for vaccinating goats against PPR disease was when the least number of animals were incubating the disease. In the tropical humid zone, as in West Africa, the optimal time for vaccination against the PPR disease is from late November to middle of December.  相似文献   

20.
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