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51.
The invasive mosquito Aedes albopictus (Skuse) (Diptera: Culicidae) has become widespread in Italy during the past decade. Also Italy has foci of canine filariasis caused by Dirofilaria (Spirurida: Onchocercidae), due to subcutaneous D. repens Railliet & Henry as well as the dog heartworm D. immitis (Leidy) transmitted by various vector mosquitoes (Diptera: Culicidae). In 2002, at Fiumicino, west of Rome (Lazio Region), 17% of dogs were found to have D. repens microfilariae in peripheral blood. To evaluate the role of Ae. albopictus as a vector of Dirofilaria in this area, female mosquitoes were collected daily, June-October 2002, landing on dog or human bait in a rural house at Focene. Mosquitoes were maintained at 27 degrees C and 70% RH for 6 days, to allow development or purging of filaria larvae, then identified and frozen for subsequent molecular assay with filaria-specific ribosomal S2-S16 primers. To distinguish specimens harbouring infective L3 Dirofilaria larvae, DNA was extracted separately from the mosquito abdomen and head-thorax. Dirofilaria species were identified by sequencing, confirmed by polymerase chain reaction of positive specimens using primers specific for D. immitis and D. repens. Dirofilaria DNA was detected in 3/154 (2%) of Ae. albopictus females examined: D. repens DNA in head-thorax and abdomen of one collected 27th July; D. immitis in the abdomen of one collected 24th September; DNA of both D. immitis and D. repens in the head-thorax of one collected 11th October 2002. Thus Ae. albopictus is a potential vector of both Dirofilarias in Italy, representing risks for veterinary and human health.  相似文献   
52.
The formulation of the culture medium for a Chinese hamster ovary (CHO) cell line has been investigated in terms of the simultaneous replacement of glucose and glutamine, the most commonly employed carbon and nitrogen sources, pursuing the objective of achieving a more efficient use of these compounds, simultaneously avoiding the accumulation of lactate and ammonium in the medium. The key factor in this process is the selection of compounds that are slowly metabolized. Among the different compounds studied, galactose and glutamate provide the best results, allowing support of cell growth with an optimal balance between nutrient uptake and cell requirements and the generation of minimal quantities of lactate and ammonium. The attained results also highlight the capacity of the cells to redistribute their metabolism as a response to the changes in medium composition.  相似文献   
53.
Most of cases of visceral larva migrans syndrome are caused by Toxocara canis larvae. Man acquires the infection by accidental ingestion of ripe eggs of the helminth. In order to find out the frequency of the presence of Toxocara sp. eggs in dog fecal specimens from public places of Santiago city in 1999 july-september a study was carried out in 84 squares and 12 parks from 32 counties. Three fecal samples were collected in each of these places, making a total of 288. Each sample was processed according to a modified Telemann method and three smears of each were microscopically examined. Toxocara sp. eggs were found in 39 (13.5%) fecal specimens. In 28/84 (33.3%) squares and in 8/12 (66.7%) parks these eggs were detected. These results make necessary the control of dogs and cats populations with the aim of reduce the presence of animals without responsible owners. It should be advisable to prevent dogs and cats defecation in public areas grounds, trying to exclude these animals from recreation areas.  相似文献   
54.
将分离纯化的HeLa细胞核仁经非离子去垢剂、核酸酶、低盐及高盐选择性抽提结合DGD包埋去包埋技术 ,在电镜下显示了HeLa细胞的核仁骨架呈精细网络结构 .BHK -2 1细胞及小鼠肝细胞的核仁骨架与HeLa细胞的核仁骨架结构相类似 .对HeLa细胞的核仁骨架的蛋白成分进行了分析 .结果表明核仁骨架蛋白组成与核基质及染色体骨架有明显差异 .HeLa细胞核仁骨架的蛋白成分主要包括分子量为48,43,36及 33ku左右的 6~ 7种多肽 .证明分子量为 43ku的肌动蛋白与 36ku的fibrillarin是构成核仁骨架的两种主要蛋白成分  相似文献   
55.
Colorectal cancer can develop through molecular, chromosomal, and epigenetic cumulative changes that transform the normal intestinal epithelium into the colorectal polyps, called conventional adenomas (CAs) or serrated polyps (SPs), recognized as precursors of invasive colorectal neoplasia. These benign lesions need to explore the morphology, histological diagnosis, and biomarkers profile to accurately characterize lesions with potential for evolution to cancer. This study aimed to correlate the immunohistochemical expression of Parkin and Adenomatous Polyposis Coli (APC; tumor suppressors), Human Apurinic/Apyrimidinic endonuclease 1 (APE1), and B-cell lymphoma-extra-large (Bcl-xL; oncogenic proteins) in sporadic colorectal polyps with clinical, endoscopic, and diagnostic data. Immunohistochemical analysis was performed on tissue microarray samples of 306 polyps. Based on the Allred score, the expressions were graduated in the cytoplasm and nucleus of superficial and cryptic cells. There was higher Parkin nuclear expression (p=0.006 and 0.010) and APC cytoplasmic expression in cryptic cells (p<0.001) in SPs. CAs, APE1 (p<0.001) and Bcl-xL (p<0.001) were more expressed in the nuclei and cytoplasms, respectively. These results are related to the biological role proposed for these proteins in cellular functions. They can contribute to the diagnosis criteria for polyps and improve the knowledge of biomarkers that could predict cancer development:  相似文献   
56.
BackgroundSoil-transmitted helminth (STH) infections are a public health problem in resource-limited settings worldwide. Chronic STH infection impairs optimum learning and productivity, contributing to the perpetuation of the poverty-disease cycle. Regular massive drug administration (MDA) is the cardinal recommendation for its control; along with water, sanitation and hygiene (WASH) interventions. The impact of joint WASH interventions on STH infections has been reported; studies on the independent effect of WASH components are needed to contribute with the improvement of current recommendations for the control of STH. The aim of this study is to assess the association of lacking access to water and sanitation with STH infections, taking into account the differences in route of infection among species and the availability of adequate water and sanitation at home.ConclusionsLack of safe water and proper sanitation pose a risk of STH infections that is distinct according to the route of entry to the human host used by each of the STH species. Interventions aimed to improve water and sanitation access should be highlighted in the recommendations for the control of STH.  相似文献   
57.
58.
目的:比较宫颈电环切除术(LEEP)与冷刀宫颈锥切术治疗宫颈上皮内瘤变(CIN)的临床疗效。方法:回顾性分析分别行LEEP(96例)与冷刀锥切术(78例)治疗的CINⅡ-Ⅲ级患者的临床资料,比较两组患者手术时间、术中出血量、脱痂期出血量及切口愈合时间。结果:LEEP组患者术中出血量(13.5±2.6 mL)、手术时间(12.8±1.9 min)分别少于或短于冷刀宫颈锥切组(26.4±3.7 mL;24.9±2.5 min)(P0.01),两组患者脱痂期出血量、术后切口愈合时间无统计学差异。结论:LEEP治疗CINⅡ-Ⅲ级患者较冷刀锥切术治疗术中出血少,手术时间短,值得临床推广。  相似文献   
59.
目的:观察脑缺血模型大鼠血清及脑组织中IGF1蛋白表达水平,以及通络救脑注射液对该因子表达水平的影响,分析通络救脑注射液的脑保护作用途径。方法:以线栓法制作大鼠大脑中动脉缺血模型(MCAO),将SD大鼠随机分为空白对照组、模型组及通络救脑注射药组,分别在造模后12小时、24小时、3天、7天4个时间点采取动物血清和脑组织,以免疫组化、酶联免疫(ELISA)以及RTPCR的方法,分别检测IGF1的表达部位及定量检测该因子的蛋白及mRNA表达水平,并测定血清NSE含量。结果:IGF1在正常脑组织有表达,在脑缺血后24小时表达增多,此后随脑缺血时间的延长不断减少;通络救脑组IGF1各时间点表达均高于模型组。模型组血清NSE水平显著升高,各时间点与正常组均有显著差异,通络救脑注射液组血清NSE水平在12小时、1天和7天时显著低于模型组。结论:大鼠脑缺血损伤后IGF1表达减少与神经元的坏死有相关性,通络救脑注射液能够提高其表达水平,对缺血损伤的脑组织发挥保护作用。  相似文献   
60.
In this work a new strategy for automatic detection of ischemic episodes is proposed. A new measure for ST deviation based on the time–frequency analysis of the ECG and the use of a reduced set of Hermite basis functions for T wave and QRS complex morphology characterization, are the key points of the proposed methodology.Usually, ischemia manifests itself in the ECG signal by ST segment deviation or by QRS complex and T wave changes in morphology. These effects might occur simultaneously. Time–frequency methods are especially adequate for the detection of small transient characteristics hidden in the ECG, such as ST segment alterations. A Wigner–Ville transform-based approach is proposed to estimate the ST shift. To characterize the alterations in the T wave and the QRS morphologies, each cardiac beat is described by expansions in Hermite functions. These demonstrated to be suitable to capture the most relevant morphologic characteristics of the signal. A lead dependent neural network classifier considers, as inputs, the ST segment deviation and the Hermite expansion coefficients. The ability of the proposed method in ischemia episodes detection is evaluated using the European Society of Cardiology ST–T database. A sensitivity of 96.7% and a positive predictivity of 96.2% reveal the capacity of the proposed strategy to perform ischemic episodes identification.  相似文献   
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