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1.
P Ghittino 《Parassitologia》1979,21(1-3):27-33
The speaker commented on the chief problems of parasitology found in Italian fresh water fish farms (troutfarming) and warm water pond farms (eel-, catfish-, cyprinids-, lagoo-fishfarmings). He discussed the most common fish losses connected in Italy with the diseases due to protozoans, worms, and crustaceans. The not yet solved and serious uncertainities which need priority in the research are, according to the speaker, the control of the amebiasis of hatchery rainbow trout, the incysted icthyophtiriasis of various fresh water fishes, the rainbow trout myxosomiasis (Whirling disease), and the argulosis of eel reared in brackish water lagoons. He concluded by emphasizing the need of a larger interest by Italian scientists on parasitic diseases of farmed fish. Without knowing and controlling them, it will be hard to program viable acquaculture industries.  相似文献   

2.
Whirling disease, caused by the pathogen Myxobolus cerebralis, leads to skeletal deformation, neurological impairment and under certain conditions, mortality of juvenile salmonid fishes. The disease has impacted the propagation and survival of many salmonid species over six continents, with particularly negative consequences for rainbow trout. To assess the genetic basis of whirling disease resistance in rainbow trout, genome-wide mapping was initiated using a large outbred F(2) rainbow trout family (n=480) and results were confirmed in three additional outbred F(2) families (n=96 per family). A single quantitative trait locus (QTL) region on chromosome Omy9 was identified in the large mapping family and confirmed in all additional families. This region explains 50-86% of the phenotypic variance across families. Therefore, these data establish that a single QTL region is capable of explaining a large percentage of the phenotypic variance contributing to whirling disease resistance. This is the first genetic region discovered that contributes directly to the whirling disease phenotype and the finding moves the field closer to a mechanistic understanding of resistance to this important disease of salmonid fish.  相似文献   

3.
This paper reviews the literature on disease interaction between wild and farmed fish and recommends strategies to reduce the disease risks to both populations. Most, if not all, diseases of farmed fish originate in wild populations. The close contact between farmed and wild fish readily leads to pathogens exchange. Aquaculture creates conditions ( e.g. high stocking levels) conducive to pathogen transmission and disease; hence pathogens can overspill back, resulting in high levels of challenge to wild populations. This is exemplified by sea lice infections in farmed Atlantic salmon. Stocking with hatchery reared fish or aquaculture escapees can affect disease dynamics in wild populations. Whirling disease has been spread to many wild rainbow trout populations in the US with the release of hatchery reared stock. The greatest impact of aquaculture on disease in wild populations has resulted from the movement of fish for cultivation. Examples of exotic disease introduction following movement of live fish for aquaculture with serious consequences for wild populations are reviewed. The salmon parasite, Gyrodactylus salaris, has destroyed wild salmon populations in 44 Norwegian rivers. Crayfish plague has wiped out European crayfish over much of Europe. Eels numbers have declined in Europe and infection with the swimbladder nematode Anguillicola crassus has in part been blamed. The impact of disease in farmed fish on wild populations can mitigated. Risk analysis methods need to be refined and applied to live fish movement and new aquacultural developments. Appropriate biosecurity strategies, based on risk assessments, should be developed to reduce pathogen exchange and mitigate the consequences.  相似文献   

4.
Whirling disease, caused by the parasite Myxobolus cerebralis, has infected rainbow trout (Oncorhynchus mykiss) and other salmonid fish in the western United States, often with devastating results to native populations but without a discernible spatial pattern. The parasite develops in a complex 2-host system in which the aquatic oligochaete Tubifex tubifex is an obligate host. Because substantial differences in whirling disease severity in different areas of North America did not seem explainable by environmental factors or features of the parasite or its fish host, we sought to determine whether ecological or genetic variation within oligochaete host populations may be responsible. We found large differences in compatibility between the parasite and various laboratory strains of T. tubifex that were established from geographic regions with different whirling disease histories. Moreover, 2 closely related species of tubificids, Limnodrilus hoffmeisteri and Ilyodrilus templetoni, which occur naturally in mixed species assemblages with T. tubifex, were incompatible with M. cerebralis. Virulence of the parasite was directly correlated with the numbers of triactinomyxon spores that developed within each strain of T. tubifex. Thus, the level of virulence was directly related to the compatibility between the host strain and the parasite. Genetic analyses revealed relationships that were in agreement with the level of parasite production. Differences in compatibilities between oligochaetes and M. cerebralis may contribute to the spatial variance in the severity of the disease among salmonid populations.  相似文献   

5.
Whirling disease is caused by the myxozoan parasite Myxobolus cerebralis, Hofer. It has been associated with a serious decline in wild rainbow trout populations in the western United States. The alternate host is the tubificid oligochaete Tubifex tubifex, and perhaps other tubificids. Tubifex is a very adaptable taxon, being found in various morphological forms. Polyploidy has been demonstrated. There is some suspicion that sibling species may be found to exist. Infection rates in tubificids are low. Related myxosporeans are associated with a variety of aquatic oligochaete worms belonging to three families, Tubificidae, Naididae and Lumbriculidae, and also with polychaetes. Myxozoans are now recognized as members of the phylum Cnidaria. Other fish parasites, such as the cestodes Archigetes and Caryophyllaeus and the nematode Eustrongylides, are transmitted by tubificids. The tubificid worm population in an ecosystem may provide an infective reservoir as the disease persists for long periods in the worm. Control of worm populations might be achieved by reducing organic inputs, lowering erosion, increasing flow and removing objects that accumulate pockets of silt. The use of pesticides is unlikely to be effective because of a lack of specific impact and consequent disruption of the whole benthic community, at least.  相似文献   

6.
Anti-predator defence behaviours of Psilochorus sphaeroides from Queensland and Smeringopus pallidus from Sri Lanka were studied in the laboratory. Whirling, in which these web-building pholcid spiders move their bodies rapidly around in circles, with legs remaining on the silk, is the most frequent response of adults to disturbance. Experiments were carried out to determine what types of stimuli elicited whirling. Forceful tactile and air movement stimuli elicited whirling, but there was no evidence that chemical stimuli from potential predators were important. Tactile stimulation was more effective than air movement. The behaviour of these pholcids was compared to that of a cosmopolitan pholcid, Pholcus phalangioides .  相似文献   

7.
Whirling disease, caused by the myxozoan parasite Myxobolus cerebralis, remains a health threat to salmonid fish in the western United States. Although various aspects of this host-parasite system have been studied, investigations examining the overall epizootiology of whirling disease in an ecosystem are lacking. Therefore, in June 1998, studies were initiated in the Rock Creek watershed of west-central Montana and continued through 2003 to assess the intensity of infection in trout using sentinel cages stationed throughout the drainage. Additional studies determined the percentage of the annelid worm, Tubifex tubifex, releasing M. cerebralis at various localities in Rock Creek and whether there was a seasonal or daily periodicity in the release of the triactinomyxon stage of the parasite from T. tubifex. Lastly, habitat and water quality parameters, and the effects of habitat restoration on transmission of M. cerebralis, were assessed. Overall, the intensity of M. cerebralis infections in sentinel trout increased significantly throughout the drainage between June of 1998 and 2003, with the biggest jump occurring between 1998 and 1999. In addition, the range of M. cerebralis expanded considerably over the period of study. There was no strict correlation between habitat condition and the occurrence of the parasite; fish became heavily infected in optimal and marginal habitats. However, fish exposed at a locality that had the lowest habitat ranking consistently had the highest intensity of infection. The parasite has apparently caused a dramatic decline in rainbow trout densities, but the brown trout population numbers have increased, and the overall fish density remains high. Although a major habitat restoration project did not seem to have an effect on decreasing disease intensity, this was not surprising because the restored area was located just downstream from a "hotspot" of infected T. tubifex.  相似文献   

8.
This article examines how the performance of a variety of Islamic music in transnational cultural circuits helps to promote the idea of a style of sacred music within the category of world music. Taking as an example the performance of the mawlawiyya, or "Whirling Dervish," music and dance by a Syrian–based ensemble, I show how the idea of an authentic local Syrian sacred music tradition requires its performance globally. I use the concept of the "world stage" to examine how musical performance practices that are represented as authentic local traditions obtain both their authenticity and their local specificity through their staging in global contexts. I further explore how such musical styles as sacred and Sufi emerge as naturalized categories in world music discourse, and how processes of differentiation and commodification reconfigure both the "local" and "global." [Keywords: world music, globalization, style, Syria, Islam]  相似文献   

9.
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   

10.
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   

11.
目的:探讨冠心病患者血清白介素18(Interleukin-18,IL-18)、白细胞分化抗原40配体(CD40L)、及高敏C反应蛋白(hs-CRP)水平在经皮冠状动脉介入术治疗前后的变化和意义。方法:选择经冠状动脉造影确诊的冠心病患者85例,根据病变程度分为单支病变组(n=32)、双支病变组(n=28)和多支病变组(n=25),采用双抗体夹心ELISA法测定PCI术前术后血清IL-18、CD40L和hs-CRP水平。结果:血清IL-18水平测定结果:多支病变组高于双支病变组,双支病变组高于单支病变组;支架置入术后显著高于术前,差异均有统计学意义(P<0.01)。血清CD40L水平测定结果:多支病变组高于双支病变组和单支病变组,差异均有统计学意义(P<0.01),双支病变组与单支病变组间差异无统计学意义(P>0.05);支架置入术后较术前显著升高,差异有统计学意义(P<0.01)。血清hs-CRP水平测定结果:多支病变组高于双支病变组,双支病变组高于单支病变组;支架置入术后显著高于术前,差异均有统计学意义(P<0.01)。结论:冠心病患者血清IL-18、CD40L和hs-CRP与冠脉病变程度密切相关,介入治疗可使冠心病患者血清IL-18、CD40L和hs-CRP水平升高,监测血清中IL-18、CD40L和hs-CRP水平变化可了解治疗效果和炎症程度。  相似文献   

12.
The aim of this study was to determine the serum levels of prolactin in patients with Behcet's disease and to evaluate its correlation with disease activity. Serum prolactin levels were measured by a chemiluminescence method in 32 patients with Behcet's disease and compared with 20 age-and sex-matched healthy controls. The patients with Behcet's disease were subdivided into two groups according to disease activity: active (18 patients; 13 men and five women, average age 34.0 +/- 6.5 (28-48) years), and inactive (14 patients; 10 men and four women, average age 32.7 +/- 3.1 (22-49 years). Patients with active Behcet's disease had higher serum prolactin levels than the inactive and control groups. Prolactin levels in patients with active Behcet's disease differed significantly from the healthy control subjects (p < 0.05) only, but not the inactive group. Four patients out of 32 (12.5%) Behcet's disease patients showed mild hyperprolactinemia. All four of these cases were from the active Behcet's disease group. Prolactin levels were correlated with ESR (p < 0.05) and CRP (p < 0.05) levels in the active BD group, but not in the inactive BD and control groups. Our results suggest a possible role for this immunoregulatory hormone in the disease expression and pathogenesis of Behcet's disease.  相似文献   

13.
BACKGROUND: Patients with inflammatory bowel disease have lower prevalence of Helicobacter pylori infection, but the exact reason for this is not yet clear. AIM: To examine whether the antibiotics frequently used in inflammatory bowel disease are responsible for the lower prevalence of H. pylori infection. Patients with chronic obstructive pulmonary disease on prolonged previous antibiotic therapy were used for comparison. METHODS: Presence/absence of H. pylori infection was detected by a (13)C-urea breath test in 133 patients with inflammatory bowel disease (82 ulcerative colitis, and 51 Crohn's disease) and compared with that of 135 patients with chronic obstructive pulmonary disease and with two age-matched control groups (200 patients each). Primary disease location, duration of disease and detailed analysis of previous and current medication (dose and duration of antibiotics, steroids, 5-aminosalicylic acid) were analysed in each cases. RESULTS: Seventeen of the 133 patients with inflammatory bowel disease [12.2% (10/82) of ulcerative colitis and 13.7% (7/51) of Crohn's disease] and 90/135 patients with chronic obstructive pulmonary disease (66.7%) were positive for H. pylori. A total of 78/200 (39%) for the inflammatory-bowel-disease-group-matched controls and 110/210 (55%) for the chronic-obstructive-pulmonary-disease-matched controls were positive for H. pylori. The history of any antibiotic or steroid therapy had no influence on H. pylori status of patients with inflammatory bowel disease. CONCLUSION: The prevalence of H. pylori compared to the age-matched controls is significantly lower in patients with inflammatory bowel disease but not in those with chronic obstructive pulmonary disease. Antibiotic use is not responsible for the lower prevalence of H. pylori infection in patients with inflammatory bowel disease.  相似文献   

14.
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   

15.
16.
西安地区空军老干部患病现况及其相关因素研究   总被引:1,自引:0,他引:1  
目的:调查西安地区老年空军人群慢性病患病情况及其生活评价的现况,分析其相关因素的影响。方法:采用整群抽样的方法对西安地区310名老年空军进行体格检查和使用生活综合评价调查表进行问卷调查。结果:在本次研究的老年空军人群中,慢性病患病率100%。同时患两种病及以上的占91.29%。患病率由高到低排名前10位的慢性病依次为高血压、冠心病、高脂血症、老年性白内障、脑血管疾病、前列腺疾病、糖尿病、慢性支气管炎、慢性胃肠道疾病、胆囊和胆道疾病。舒张压异常、体检白细胞指标异常的人群患脑血管疾病的优势比分别是2.16、3.95(P<0.05);甘油三脂异常的人群患高脂血症的优势比是4.74(P<0.001);在健康自评和心理卫生评定中、差的人群患冠心病的优势比分别是1.85、1.64(P<0.001);体能检查中、差的人群惠老年性白内障的优势比是1.48(P<0.05);生活功能、社会交往和活动强度中、差的人群患脑血管疾病的优势比分别是3.40、2.22、2.92(P<0.001)。结论:应有针对性、有重点地开展危险因素的早期干预,促进预防和医疗两大系统的协作,才能有效地控制老年人慢性病的发生。  相似文献   

17.
A strong female predominance is a well-recognized feature of human lupus. The mechanism by which sex influences disease expression and severity is not fully understood. To address this question, we used the parent-into-F(1) (p-->F(1)) model of chronic graft-vs-host disease (cGVHD) in which lupus-like humoral autoimmunity and renal disease are induced in normal F(1) mice. An advantage of this model is that the pathogenic T cells driving disease (donor strain) can be studied separately from nonspecifically activated T cells (host strain). We observed that lupus-like disease using female donor and host mice (f-->F cGVHD) is characterized by more severe long-term disease (glomerulonephritis) than with male donor and host (m-->M cGVHD). Interestingly, differences in disease parameters could be seen at 2 wk after parental cell transfer, as evidenced by a 2- to 3-fold greater engraftment of donor CD4(+) T cells in f-->F cGVHD mice, which persisted throughout disease course. Enhanced engraftment of donor CD4(+) T cells in f-->F cGVHD mice was not due to differences in splenic homing, alloreactive precursor frequency, initial proliferation rates, or apoptotic rates, but rather to sustained high proliferation rates during wk 2 of disease compared with m-->M cGVHD mice. Crossover studies (m-->F, f-->M) demonstrated that enhanced donor CD4(+) T cell proliferation and engraftment segregate with the sex of the host. These results demonstrate that the sex of the recipient can influence the expansion of pathogenic T cells, thus increasing long-term the burden of autoreactive T cells and resulting in greater disease severity.  相似文献   

18.
Adrenal computed tomographic (CT) scanning was conducted in twelve patients with Addison's disease during the clinical course. In tuberculous Addison's disease (n = 8), three of four patients examined during the first two years after disease onset had bilaterally enlarged adrenals, while one of four had a unilaterally enlarged one. At least one adrenal gland was enlarged after onset in all six patients examined during the first four years. Thereafter, the adrenal glands may atrophy bilaterally, in contrast to adrenal glands in idiopathic Addison's disease, which atrophy bilaterally from disease onset (n = 2). Adrenal calcification was a less sensitive clue in tracing pathogenesis, i.e., adrenal calcification was observed in five of eight patients with tuberculous Addison's disease, but not in idiopathic patients. Thus, adrenal CT scanning could show the etiology of Addison's disease (infection or autoimmunity) and the phase of Addison's disease secondary to tuberculosis, which may be clinically important for initiating antituberculous treatment.  相似文献   

19.
目的:探讨血清同型半胱氨酸(Hcy)、高敏C反应蛋白(hs-CRP)及肱踝脉搏波传导速度(baPWV)与冠心病患者冠脉病变程度的相关性。方法:选取2015年6月-2017年10月期间承德医学院附属医院收治的疑似冠心病的患者324例为研究对象,根据冠状动脉造影结果分为冠心病组213例与非冠心病组111例,根据不同冠脉病变程度将冠心病组分为单支病变组87例,双支病变组74例,多支病变组52例,检测并对比所有患者血清Hcy、hs-CRP水平及baPWV值,分析Hcy、hs-CRP水平及baPWV值与冠心病患者冠脉病变程度相关性。结果:冠心病组患者血清Hcy、hs-CRP水平及baPWV值较非冠心病组升高(P0.05)。冠心病组不同冠脉病变程度患者血清Hcy、hs-CRP水平及baPWV值整体比较差异有统计学意义(P0.05),多支病变组与双支病变组患者血清Hcy、hs-CRP水平及baPWV值高于单支病变组,且多支病变组高于双支病变组,差异有统计学意义(P0.05)。经Pearson相关性分析显示,Hcy、hs-CRP及baPWV均与冠心病患者冠脉病变程度呈正相关(P0.05)。结论:冠心病患者血清Hcy、hs-CRP水平及baPWV值高于非冠心病者,且血清Hcy、hs-CRP水平及baPWV值随着冠心病患者冠脉病变程度的加重而升高,与冠脉病变程度呈正相关。  相似文献   

20.
In order to identify mediators involved in immune-mediated disease regression, the pleural cytokine and histopathological profile was evaluated in tuberculous pleurisy patients with varied disease duration and clinical presentation, previous to chemotherapy. Interleukin (IL)-10, interferon (IFN)-gamma and tumor necrosis factor (TNF) levels in pleural fluids were shown to decrease with disease time. IL-10 was positively correlated with IFN-gamma, TNF and necrosis area in pleural sections. To parallel these findings with disease regression, individuals showing fever, anorexia, and progressive exudate in the pleural cavity (active disease) were compared with patients without symptoms and with a decrease in exudate volume (regressive disease). IFN-gamma and TNF levels were lower in regressive disease, as well as reduced necrosis area in pleural sections. Our results indicate that tissue destruction and a prominent Th1 response mark the early phase of tuberculous pleurisy and suggest that down-modulation of this response, with the possible participation of IL-10, is associated with disease resolution.  相似文献   

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