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排序方式: 共有117条查询结果,搜索用时 15 毫秒
11.
Y Ohkawara XF Lei MR St?mpfli JS Marshall Z Xing M Jordana 《Canadian Metallurgical Quarterly》1997,16(5):510-520
Selective accumulation of eosinophils and activated CD4+ cells is now considered a central event in the pathogenesis of asthma, and this process is thought to be mediated by a number of cytokines including tumor necrosis factor-alpha (TNF-alpha), granulocyte-macrophage colony-stimulating factor (GM-CSF), and the Type 2 cytokines interleukin-4 (IL-4) and IL-5. To carry out a detailed time-course analysis of cellular changes in the bronchoalveolar lavage fluid (BAL), peripheral blood (PB), and bone marrow (BM), and of changes in the aforementioned cytokines in BAL and serum, Balb/c mice were sensitized by intraperitoneal injection with ovalbumin (OVA) adsorbed to aluminum hydroxide on two occasions 5 days apart, and were subjected to an OVA aerosol challenge 12 days after the second sensitization. This resulted in an airways inflammatory response characterized by early transient neutrophilia, marked eosinophilia, and, to a lesser extent, lymphocytosis in the BAL. Inflammatory events were first observed 3 h and 24 h after antigen challenge in the lung tissue and BAL, respectively, and lasted for 21 days. In the BM, we detected a 1.5- and 5-fold increase in the total number of cells and eosinophils, respectively, 4 days after the second sensitization. This was followed by a decrease, although BM eosinophilia remained clearly present at the time of antigen challenge. A second eosinopoietic event was observed in the BM shortly after challenge and reached a peak at day 3. BM cellularity returned to normal at day 21 after challenge. Serum OVA-specific IgE was first detected 3 days following the second sensitization (150 ng/ml). IgE levels then decreased but remained at the 75 ng/ml range at the time of the aerosol challenge. During the sensitization period, TNF-alpha (approximately 25 pg/ml), IL-4 (approximately 40 pg/ml), and IL-5 (approximately 250 pg/ml) were detected in serum, but not in the BAL fluid (BALF) and returned to background levels at the time of the antigen challenge. After antigen challenge, TNF-alpha, IL-4, IL-5, and GM-CSF were detected in serum. Peak levels were observed at 3 h (approximately 40 pg/ml), 3 h (approximately 120 pg/ml), 12 h (approximately 350 pg/ml), and 3 h (approximately 10 pg/ml), respectively, and returned to background levels 24 h after challenge. In the BALF, we detected peak levels of TNF-alpha, IL-4, IL-5, and GM-CSF at 6 h (approximately 250 pg/ml), 24 h (approximately 140 pg/ml), 24 h (350 pg/ml), and 3 h (approximately 10 pg/ml), respectively, with a return to background levels 5 days after challenge. No IL-10 could be detected at any time point during sensitization or after challenge in either serum or BAL. We also detected approximately 40 pg/ml of interferon-gamma (IFN-gamma) in the serum of normal untreated mice. Serum IFN-gamma levels fluctuated during sensitization and after challenge, but never exceeded those observed in untreated mice. Thus, the cytokine profile observed in this experimental model of allergic inflammation is characterized by IL-4 and IL-5 dominance, with an apparently minor TNF-alpha and GM-CSF contribution and relatively low or undetectable levels of IFN-gamma and IL-10. 相似文献
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F Botía Martínez M Canteras Jordana L Párraga Sánchez 《Canadian Metallurgical Quarterly》1995,69(3-4):283-294
BACKGROUND: The aims of this paper are twofold: to closely study tobacco and alcohol consumption among the adult population in the Autonomous Community of Murcia and to observe the relation between such habits and the morbidity of the population polled. METHODS: We study 1,128 patients admitted to the Virgen de la Arrixaca Hospital, the centre of reference in this Community, in 1992. The survey is done in all the hospital departments on patients and eighteen years and over. RESULTS: 37.4% of the persons polled are smokers, and 67.4% consume alcohol. The prevalence of smokers decreases with age: 57.4% of the patients aged under 30 years are smokers, compared to 14.7% of those aged over 70 years. The prevalence of tobacco-related malignant tumours is 0.6% in the non-smokers, and 8.0% in the smokers and ex-smokers with a consumption of more than 10 cigarettes/day. The prevalence of malignant tumours in the digestive organs is 7.9% in patients consuming alcohol daily and 1.8% in non-drinkers. CONCLUSIONS: We note a decrease in tobacco consumption in the patient population, which is in line with the decrease in tobacco consumption in the general population of Spain as stated in the literature. Wine is the preferred drink of the study population overall, and beer in those aged under fifty years. 相似文献
13.
Divari S Mulasso C Uslenghi F Cannizzo FT Spada F De Maria R Brina N Biolatti B 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2011,28(12):1677-1686
The monitoring of gene regulation via mRNA levels to detect anabolic sex steroid administration in cattle is a novel approach to detecting the illicit treatment of livestock in meat production. A previous study revealed that progesterone receptor (PR) gene expression levels were increased in the bulbourethral glands and prostates of 17β-oestradiol-treated prepubertal calves, suggesting that the PR can be used as a specific molecular biomarker for oestrogen treatment. The aim of this study was to verify the specificity and applicability of the PR to detect the illegal use of 17β-oestradiol in sexually mature beef cattle. Accessory sex glands were sampled from 42 male beef cattle that were divided into six experimental groups, including two control groups, K1 and K2. Group A cattle were treated with 17β-oestradiol (five weekly intramuscular doses of 20 mg), and group B cattle were treated with dexamethasone (40 daily doses of 0.7 mg per os). Group C cattle received an implant of Revalor-200 (200 mg of trenbolone acetate and 20 mg of 17β-oestradiol), and group D cattle received Revalor-200 plus dexamethasone (0.7 mg daily per os). 17β-Oestradiol, either alone or in combination with other steroids, up-regulated the PR gene and protein expression, even in the absence of detectable histological changes in the accessory sex glands, confirming the high sensitivity of PR gene expression as an indirect diagnostic screening tool to detect illicit oestrogen treatment in sexually mature male bovine. 相似文献
14.
Goat acetyl-coenzyme A carboxylase alpha: molecular characterization, polymorphism, and association with milk traits 总被引:1,自引:0,他引:1
Badaoui B Serradilla JM Tomàs A Urrutia B Ares JL Carrizosa J Sànchez A Jordana J Amills M 《Journal of dairy science》2007,90(2):1039-1043
Acetyl-coenzyme A carboxylase α (ACACA), the major regulatory enzyme of fatty acid biosynthesis, catalyzes the conversion of acetyl-CoA to malonyl-CoA. We have sequenced 5.5 kb of the goat ACACA cDNA in 18 individuals. The translated cDNA sequence encodes 1,832 AA and shares a high AA identity (99%) with the ovine and bovine ACACA orthologous sequences. One silent single nucleotide polymorphism was identified at exon 45 (C5493T). The genotyping of this polymorphism in 4 goat breeds, Murciano-Granadina, Teramana, Majorera, and Malagueña, showed that it was segregating in all 4 breeds at variable frequencies. In addition, a mixed animal model was used to evaluate the association of C5493T genotypes with milk traits. Results from this study show that the C5493T mutation was suggestively associated with fat yield, lactose content, and somatic cell count. 相似文献
15.
RA Mangiafico LS Malatino M Santonocito RS Spada G Polizzi G Tamburino 《Canadian Metallurgical Quarterly》1996,15(3):240-244
This study investigated the Psychosocial adjustment in 40 patients who received orthotopic liver transplantation (OLT) for several endstage liver diseases. Twenty patients were grafted because they suffered from liver Cancer as well as cirrhosis. Particular attention was paid to evaluating whether cancer could affect recipients' coping with transplant. Each patient underwent a semi-structured interview to obtain information on their psychosocial life, relationship with the donor, organ acceptance and life expectancy. Interview was performed I year after transplantation. A psychodiagnostic evaluation was also performed using a Minnesota Multiphasic Personality Inventory (MMPI) and a Human Figure Test. Psychosocial adaptation in everyday life following liver transplantation seemed good in most of the patients, whatever the indication for transplantation might be. It can he seen that by replacing the diseased organ a high percentage of oncological patients overcame their fear of cancer. 相似文献
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M Lusuardi A Capelli S Carli EL Spada A Spinazzi CF Donner 《Canadian Metallurgical Quarterly》1993,103(6):1783-1791
Bacterial extracts can act as immune stimulants and in some instances have been used, rather empirically, to prevent recurrent infections in the nonimmunocompromised host. Some agents are administered via oral route with the goal to increase airways immune defenses. In animal models and in normal humans, gut-associated lymphoid tissue (GALT) stimulation is able to induce a generalized response by the whole mucosal-associated lymphoid tissue (MALT). The aim of this placebo-controlled, double-blind, parallel-group study was to evaluate whether the stimulation of the GALT through oral administration of a polyvalent bacterial extract (BE) could lead to significant immune modifications either systemically or locally in the respiratory tract in patients suffering from chronic bronchitis. We selected 20 subjects (5 nonsmokers, 6 smokers, and 9 ex-smokers) for at least 3 years. According to a balanced-block randomization method, ten patients received active treatment and ten received placebo. Either drug or placebo was to be taken as one capsule daily the first 10 days of 3 consecutive months. Each capsule of the active product contained 7 mg of a BE obtained from eight different bacterial strains. On entry (T0) and 90 days after beginning of treatment (T90), all patients underwent bronchoalveolar lavage (BAL) and peripheral blood withdrawal to assay BAL fluids and serum samples for immune parameters. The BAL recoveries, cellularity, cell differentials, and lymphocyte subsets (CD19, CD3, CD4, CD8) did not show significant differences. IgG/albumin and IgA/albumin values were not significantly different, but IgA/albumin was significantly increased in the treatment (T0 = 0.14, 0.01 to 0.27, median and range, T90 = 0.15, 0.08 to 0.45, p = 0.028) vs the placebo group when data from current smokers were excluded. Functional tests on alveolar macrophages (AM) (leading front stimulated motility and superoxide anion-O2(-)-release) showed a significant increase of random migration (T0 = 10.6, 7.0 to 23.6, T90 = 13.4, 8.1 to 28.8 microns, p = 0.02) and of stimulated motility after FMLP 10(-7) M (T0 = 13.2, 8.3 to 46.4, T90 = 18.3, 8.4 to 49.6 microns, p = 0.04), a significant increase of O2- release in basal conditions (T0 = 6.0, 1.7 to 30.5 nM/10(6) AM/10', T90 = 11.1, 5.5 to 24.5, p = 0.05) and after stimulation with opsonized zymosan (T0 = 17.7, 4.7 to 35.2, T90 = 22.1, 13.8 to 53.3, p = 0.009) in the treatment group only. Data were not significantly different in the placebo group between T0 and T90. No modifications in systemic immunity were ever observed.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
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