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排序方式: 共有210条查询结果,搜索用时 26 毫秒
1.
Multi-agent chemotherapy successfully induces remission in most naïve, high-grade canine lymphoma patients; however, disease recurrence is common. MOPP (mechlorethamine, vincristine, procarbazine, and prednisone) is an effective rescue protocol used to re-induce remission, but is associated with gastrointestinal toxicity and can be a less desirable option for patients that previously failed vincristine-containing protocols. Therefore, alternative members of the vinca alkaloid family, such as vinblastine, could be potentially advantageous as substitutes for vincristine to reduce gastrointestinal toxicity and chemoresistance. The objective of this study was to report the clinical outcomes and toxicity of 36 dogs with relapsed or refractory multicentric lymphoma treated with a modified MOPP protocol whereby vincristine was replaced with vinblastine (MVPP). The overall response rate to MVPP was 25% with a median progression free survival of 15 days and a median overall survival of 45 days. MVPP at the prescribed doses resulted in modest and transient clinical benefit, but was well tolerated with no treatment delays or hospitalizations secondary to side effects. Given the minimal toxicity, dose intensification could be considered to improve clinical responses.  相似文献   
2.
Platanus accrifolia Hyb. is attacked by a serious disease: the canker stain. The responsible agent is an Ascomycete, Ceratocystis fimbriata f. platani which is extremely virulent. During the last twelve years, it has killed more than 1,800 plane trees in the streets of Marseilles. This disease was until now strictly localized in north America.  相似文献   
3.
The objective of this paper was to study the changes of some cytokines and neuroendocrine hormones in vaccinated and unvaccinated pigs that were naturally infected by a PRRSV-1 (porcine reproductive and respiratory syndrome virus) heterologous field strain. We analyzed gene expression of pro-inflammatory (TNF-α, IL-1β, MCP-1, IL-6), pro-immune (IFN-γ) and anti-inflammatory cytokines (IL-10) in PBMC, as well as hormonal (GH and cortisol) levels in blood samples of pigs obtained in a field trial previously reported [Martelli P, Gozio S, Ferrari L, Rosina S, De Angelis E, Quintavalla C, et al. Efficacy of a modified-live porcine reproductive and respiratory syndrome virus (PRRSV) vaccine in pigs naturally exposed to a heterologous European (Italian cluster) field strain: clinical protection and cell-mediated immunity. Vaccine 2009;27:3788-99]. All vaccinated pigs showed an increase in pro-inflammatory and pro-immune cytokine gene expression with respect to controls and a prompt increase in GH that could be consistently associated with pro-inflammatory cytokines in sustaining innate immunity; moreover, the higher levels of cortisol indicates the activation of the hypothalamus-pituitary-adrenal (HPA) axis response. In contrast, unvaccinated pigs showed down-regulation of the cortisol and GH responses, and the pro-inflammatory and pro-immune cytokines remained at a basal or low level, with an increase of TNF-α and IL-6 in association with a higher level of IL-10 in the late phase of natural infection. The associated trends of pro-inflammatory and anti-inflammatory cytokines together with the cortisol level demonstrate that a previous vaccination promotes an early immune responsiveness in pigs and a more efficient control of inflammation in the late phase of infection with a heterologous PRRSV isolate; both events could sustain clinical protection.  相似文献   
4.
Mercury (Hg) contamination of miners, riparian and Indian populations and fish in the Amazon region, due to gold extracting activities, has been studied. Samples of hair, urine, and blood of Indians and prospectors, and hair from riparian fish-eating population and fishes from Madeira river, respectively, were collected and analyzed by Cold Vapor, Atomic Absorption Spectrometry (CV-AAS) techniques. The results obtained showed that the aquatic food chains in the Amazonian ecosystems are contaminated by methylmercury (MeHg), exposing Indians, prospectors and riverines to thr risk of severe health hazard. The highest levels of contamination, based upon hair analysis, were found in riparian of the Madeira river, followed by Cuniã Lake population, Indians (Fresco river) and prospectors, in that order. Blood analysis showed 59% of the samples from Indians and 33% from prospectors with Hg contents above 10 ng mL?1. Analysis of urine, on the other hand, showed 44% of Indians with Hg levels below the detection limit (d.l.), and 30% above 20 ng mL?1, whereas 38% of the prospectors presented Hg concentrations over 20 ng mL?1, and 20% below the d.l. These results prove that prospectors, who hardly ever eat fish but are badly exposed to inorganic Hg vapor, are ocupationally contaminated, while the rest of the populations under survey are exposed to environmental contamination by Hg, through polluted fish ingestion.  相似文献   
5.
6.
Acrylamide exposure was investigated in subgroups of the EPIC study population (510 subjects from 9 European countries, randomly selected and stratified by age, gender, and smoking status) using hemoglobin adducts of acrylamide (HbAA) and its primary metabolite glycidamide (HbGA). Blood samples were analyzed for HbAA and HbGA by HPLC/MS/MS. Statistical models for HbAA and HbGA were developed including body mass index (BMI), educational level, and physical activity. A large variability in acrylamide exposure and metabolism between individuals and country groups was observed with HbAA and HbGA values ranging between 15-623 and 8-377 pmol/g of Hb, respectively. Both adducts differed significantly by country, sex, and smoking status. HbGA values were significantly lower in high alcohol consumers than in moderate consumers. With increasing BMI, HbGA in nonsmokers and HbAA in smokers decreased significantly. In the assessment of potential health effects related to acrylamide exposure, country of origin, BMI, alcohol consumption, sex, and smoking status should be considered.  相似文献   
7.
An analysis of the spatial trend of concentrations and of the correlation between heavy metals and total suspended matter was performed in a multidisciplinary study of transport of pollutants in the marine coastal area involving in situ investigations, remote sensing techniques and modeling. This paper presents results concerning the chemical behavior of heavy metals (Cu, Cd, Pb) in the North Adriatic Sea and in particular in the marine deltaic area of the Po river. The samples were collected during the JRC Remote Sensing Campaigns ADRIA 84 and ADRIA 85, carried out in the entire North Adriatic Sea and in the selected area in front of the Po when passing from the fluvial to the marine environment. In the dissolved phase, Cu undergoes a dilution process consistent with the mixing theory, while there is a tenfold increase in Pb concentrations. A pronounced tendency to augment the level in the dissolved phase is observed for all three elements in the pelagic waters. In the particulate phase, Cd and Cu, after a diminution in the nearshore stations, their concentration increases as the pelagic area is approached. The total amount of heavy metals in solid phase of the water decreases according to the dispersion and the sedimentation processes of the fluvial load in the marine water. A satisfactory correlation was found between the Cu and Pb with the total suspended matter (TSS). An attempt was made to characterize sediments and suspended matter in order to assess the role of the organic and mineralogical components on heavy metal behavior.  相似文献   
8.
Fish in the Superorder Ostariophysi possess large epidermal club cells that release chemical cues warning nearby conspecifics of danger. Despite the long‐held assumption that such club cells evolved under the selective force of predation, recent studies demonstrated that predation has no effect on club cell investment. Rather, club cells have an immune function and cell production may be stimulated by skin‐penetrating pathogens and parasites. The current work investigates whether fathead minnows, Pimephales promelas, alter their club cell characteristics based on variation in infection risk. In a 2 × 3 design, we exposed minnows to infective cysts of two oomycete species (Saprolegnia ferax and S. parasitica) at three different concentrations (2, 20 or 200 cysts L?1). Club cell characteristics (number and size) were quantified 12 days after exposure. Saprolegnia parasitica is thought to be more pathogenic than S. ferax, hence we predicted greater club cell investment and a larger turnover rate of cells by minnows exposed to S. parasitica than S. ferax. We also predicted that minnows exposed to higher numbers of cysts should invest more in club cells and have a higher turnover rate of cells. We found no difference in club cell density or size between fish exposed to the two Saprolegnia species; however, fish exposed to high concentrations of pathogens had smaller club cells than those exposed to low concentrations, indicating a higher rate of turnover of cells in the epidermis.  相似文献   
9.
The H1N1, H3N2 and, more recently, H1N2 subtypes of influenza A virus are presently co‐circulating in swine herds in several countries. The objectives of this study were to investigate the pathogenesis of Sw/Italy/1521/98 (H1N2) influenza virus, isolated from respiratory tissues of pigs from herds in Northern Italy, and to evaluate its potential cross‐protection against the Sw/Fin/2899/82 (H1N1) strain. In the pathogenesis test, eight pigs were intranasally infected with H1N2 virus; at pre‐determined intervals, these animals were killed and necropsied, along with eight uninfected animals. In the cross‐protection test, sixteen pigs were infected by intranasal (i.n.) and intratracheal (i.t.) routes with either H1N2 or H1N1 virus. Twenty days later, all pigs were challenged (by the same route), with either the homologous H1N2 or heterologous H1N1 virus strains. Control group was inoculated with culture medium alone. On post‐challenge days (PCD) 1 and 3, two pigs from each infected group, along with one control pig, were killed. Clinical, virological, serological and histopathological investigations were performed in both the pathogenicity and cross‐protection tests. In the pathogenicity test, mild clinical signs were observed in two pigs during 3 and 4 days, respectively. Virus was isolated from two pigs over 6 days and from lung samples of pigs killed on post‐infection days 2 and 4. Seroconversion was detected in the two infected animals killed 15 days after infection. In the cross‐protection study, mild clinical respiratory signs were detected in all pigs infected with either the H1N2 or H1N1 virus. The virus was isolated from nasal swabs of almost all pigs till 6 days. After the challenge infection, the pigs remained clinically healthy and virus isolation from the nasal secretions or lung samples was sporadic. Antibody titres in H1N1 or H1N2 infected groups were similar, whereas the H1N2 sub‐type induced less protection against re‐infection by homologous and heterologous virus than H1N1 sub‐type. The controls had no signs of the disease. In the H1N2 infected pigs, a reduced number of goblet cells in nasal and tracheal mucosa and small foci of lymphomononuclear cell infiltrates in the submucosa were detected. Furthermore, the goblet cell reduction was related to the time of infection. Diffuse mild interstitial pneumonia was also recorded in pigs infected with the H1N2 virus and challenged with either H1N1or H1N2 pigs. These studies showed the moderate virulence of the H1N2 virus and a partial cross‐protection against heterologous infection.  相似文献   
10.
Barley grains contain a relevant amount of soluble fibre (i.e. β-glucans) and can be used for production of foods with healthy functions. To produce barley flours enriched in β-glucans, grain micronization and air classification of the flour was used, and a method to predict the relationship between the yield of the enriched flour and its β-glucan content was developed. This method is based on a series of sortings of micronized flour, with a progressive increase in the yield of a selected fraction; a curve for β-glucan enrichment vs. yield can then be calculated. Thus, the most suitable combination of yield and β-glucan content can be chosen. We tested this approach on two hull-less barleys with different starch type, and obtained barley flour fractions with twice the β-glucan concentration that the grain had. Enriched flour fractions with 11.2 and 15.6% β-glucans were obtained from cultivars Priora (hull-less) and CDC Alamo (waxy, hull-less), respectively, with a good flour yield (about 30%). We suggest that our method can be adopted for finely tuning the enrichment process to meet the industry's needs.  相似文献   
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