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221.
222.
Magda Beretta Vicky Britto Tania Mascarenhas Tavares Sonilda Maria Teixeira da Silva Adelmo Lowe Pletsch 《Journal of Soils and Sediments》2014,14(7):1278-1286
Purpose
The Todos os Santos Bay is the largest bay in Brazil and receives drainage from various watersheds. For more than 450 years, it was the main destination for the domestic and hospital sewage from the city of Salvador, Bahia. With the growing concern regarding the presence of pharmaceutical and personal care products (PPCPs) in the environment, an investigation was undertaken to determine the presence and levels of some commonly used drugs (i.e., atenolol, caffeine, carbamazepine, diazepam, diclofenac, erythromycin, ibuprofen) and personal care products (i.e., galaxolide, tonalide), using sediments as an indicator of their presence in the water column.Material and methods
Surficial sediment samples from 17 stations located in the intertidal zone of the Todos os Santos Bay and infralittoral zone along the north coast of Salvador were tested for the presence of some PPCPs using LC-MS/MS (for drugs) and GC-MS/MS (for fragrances).Results and discussion
The PPCPs examined were present in all sediment samples at levels of parts per billion of dry sediment. The highest concentrations were found for the fragrances galaxolide (52.5 ng g?1) and tonalide (27.9 ng g?1), followed by caffeine (23.4 ng g?1) and pharmaceuticals ibuprofen (14.3 ng g?1), atenolol (9.84 ng g?1), carbamazepine (4.81 ng g?1), erythromycin (2.29 ng g?1), diclofenac (1.06 ng g?1), and diazepam (0.71 ng g?1).Conclusions
Pharmaceuticals were found to be ubiquitous in the sediments of the study areas. The texture of the sediment was an important factor in PPCPs fixation and deposition. The concentrations of all PPCPs had statistically significant positive correlations with the percentage of clay in the sediments. 相似文献223.
Batista JS Rodrigues CM García HA Bezerra FS Olinda RG Teixeira MM Soto-Blanco B 《Veterinary research》2011,42(1):63
ABSTRACT: Changes in cerebrospinal fluid (CSF) and anatomical and histopathological central nervous system (CNS) lesions were evaluated, and the presence of Trypanosoma vivax in CNS tissues was investigated through PCR. Twelve adult male goats were divided into three groups (G): G1, infected with T. vivax and evaluated during the acute phase; G2, infected goats evaluated during the chronic phase; and G3, consisting of non-infected goats. Each goat from G1 and G2 was infected with 1.25 × 105 trypomastigotes. Cerebrospinal fluid (CSF) analysis and investigation of T. vivax was performed at the 15th day post-infection (dpi) in G1 goats and on the fifth day after the manifestation of nervous system infection signs in G2 goats. All goats were necropsied, and CNS fragments from G1 and G2 goats were evaluated by PCR for the determination of T. vivax. Hyperthermia, anemia and parasitemia were observed from the fifth dpi for G1 and G2, with the highest parasitemia peak between the seventh and 21st dpi. Nervous system infection signs were observed in three G2 goats between the 30th and 35th dpi. CSF analysis revealed the presence of T. vivax for G2. Meningitis and meningoencephalitis were diagnosed in G2. PCR were positive for T. vivax in all the samples tested. In conclusion, T. vivax may reach the nervous tissue resulting in immune response from the host, which is the cause of progressive clinical and pathological manifestations of the CNS in experimentally infected goats. 相似文献
224.
Pimenta EL Teixeira Neto FJ Sá PA Pignaton W Garofalo NA 《Equine veterinary journal》2011,43(3):332-340
Reasons for performing study: Bradycardia may be implicated as a cause of cardiovascular instability during anaesthesia. Hypothesis: Hyoscine would induce positive chronotropism of shorter duration than atropine, without adversely impairing intestinal motility in detomidine sedated horses. Methods: Ten minutes after detomidine (0.02 mg/kg bwt, i.v.), physiological saline (control), atropine (0.02 mg/kg bwt) or hyoscine (0.2 mg/kg bwt) were randomly administered i.v. to 6 horses, allowing one week intervals between treatments. Investigators blinded to the treatments monitored cardiopulmonary data and intestinal auscultation for 90 min and 24 h after detomidine, respectively. Gastrointestinal transit was assessed for 96 h via chromium detection in dry faeces. Results: Detomidine significantly decreased heart rate (HR) and cardiac index (CI) from baseline for 30 and 60 min, respectively (control). Mean ± s.d. HR increased significantly 5 min after atropine (79 ± 5 beats/min) and hyoscine (75 ± 8 beats/min). After this time, HR was significantly higher after atropine in comparison to other treatments, while hyoscine resulted in intermediate values (lower than atropine but higher than controls). Hyoscine and atropine resulted in significantly higher CI than controls for 5 and 20 min, respectively; but this effect coincided with significant hypertension (mean arterial pressures >180 mmHg). Auscultation scores decreased from baseline in all treatments. Time to return to auscultation scores ≥12 (medians) did not differ between hyoscine (4 h) and controls (4 h) but atropine resulted in significantly longer time (10 h). Atropine induced colic in one horse. Gastrointestinal transit times did not differ between treatments. Conclusion: Hyoscine is a shorter acting positive chronotropic agent than atropine, but does not potentiate the impairment in intestinal motility induced by detomidine. Because of severe hypertension, routine use of anticholinergics combined with detomidine is not recommended. Potencial relevance: Hyoscine may represent an alternative to atropine for treating bradycardia. 相似文献
225.
试验以民猪为试验材料,长白猪为对照组,分别在1、2.5、4、6、8月龄时进行卵巢、输卵管和子宫取样,对促乳素受体(PRLR)基因表达的发育性变化规律进行研究。结果表明,生殖器官中PRLR的表达量与生殖器官的解剖指标存在正相关。PRLR在1、2.5、4、6和8月龄的民猪和长白猪的卵巢、输卵管和子宫中均有表达。民猪和长白猪卵巢PRLR mRNA表达水平从1月龄至8月龄呈现逐渐上升趋势,在8月龄达到最高水平,民猪卵巢PRLRmRNA表达水平显著高于长白猪(P〈0.05)。民猪和长白猪输卵管PRLR mRNA表达量随月龄增加呈上升趋势,在8月龄达到最高水平,品种间差异不显著。民猪子宫PRLR mRNA表达量随月龄增加而升高,在6月龄达到最高水平,8月龄显著下降(P〈0.05),长白猪子宫PRLR mRNA表达量随月龄增加而升高,在8月龄达到最高水平,品种间在6月龄差异显著(P〈0.05)。 相似文献
226.
马铃薯花药培养影响因素的研究 总被引:6,自引:2,他引:6
采用克新13号、克9723-20和讷16等8份马铃薯品种(系)为试验材料,采用L3(2 81×48)正交设计,对影响马铃薯花药褐化、愈伤组织诱导率和胚状体发生率等因素进行了系统研究。结果表明,马铃薯花药培养对基因型有很大的依赖性,讷16、克9723-20、俄8和波C等4份材料具有较强的花药培养再生能力;花药接种密度对褐化率影响较大,40个.瓶-1的花药接种密度比较合适;硝酸银浓度30 mg.L-1、活性炭浓度200 mg.L-1能有效地减轻花药的褐化程度。植物生长调节剂对愈伤组织诱导影响最大,NAA 0.5 mg.L-1、2,4-D 1.0 mg.L-1、KT 0.5 mg.L-1的配比适合多数材料愈伤组织的形成和胚状体的发生,以麦芽糖代替蔗糖可以提高愈伤组织的诱导率;培养基中加入马铃薯提取液能够促进胚状体的发生。 相似文献
227.
228.
Marcelo Grandi Teixeira José Guilherme Marinho Guerra Dejair Lopes de Almeida Adelson Paulo Araújo Avilio Antonio Franco 《Journal of plant nutrition》2013,36(10):1599-1611
Abstract An experiment was conducted in the greenhouse to evaluate the effects of seed phosphorus (P) concentration on growth, nodulation, and nitrogen (N) and P accumulation of three common bean (Phaseolus vulgaris L.) cultivars. Seeds were produced under low or high soil P levels, and soaked, or not, in 200 mM KH2PO4 solution. The experiment had a 3×3×2×2 factorial block design: three cultivars (ICA Col 10103, Carioca and Honduras 35), three levels of applied P (15, 30 and 45 mg P kg?1 soil), two native seed P concentrations, and two seed soaking treatments. Plants were harvested at flowering. Soaked seeds increased the number, dry mass and P content of nodules, but did not affect plant growth. Plants originated from seeds with high native P concentration presented higher shoot dry mass and nodule number and mass at every soil P level, and were less responsive to increased soil P supply, than plants from low seed P. In plants from seeds with high P, soil P levels did not alter significantly root dry mass, while in plants from seeds with low P bean cultivars expressed wider differences in root dry mass. The genotypic variability of nodulation was influenced by soil P levels and seed P concentration. Both higher soil or seed P supply enhanced N and P accumulation in shoots. These results indicate that a high seed P concentration produces plants less dependent on soil P supply, and can enhance nodulation and N2 fixation of common bean. Seed P supply affected the cultivar performance, and should be considered in evaluation of bean genotypes. 相似文献
229.
为保障芦蒿作为茎叶菜食用的安全性,通过温室盆栽试验,研究了4种芦蒿对cd积累与转运的基因型差异。结果表明,同-Cd处理水平下4种芦蒿品种干物重变化差异显著(P〈0.05),且随着cd处理水平的增加4种芦蒿品种干物重均呈现先上升后下降的趋势,在100mg·kg-1时达到最大。随着土壤Cd处理浓度的增大,4种芦蒿叶片抗氧化酶活性呈现先上升后下降的趋势,且伏秋芦蒿和白芦蒿抗氧化酶活性下降幅度大于大叶青芦蒿和青白芦蒿。4种芦蒿基因型可食部分(茎)Cd含量、富集系数(BFs)和转运系数(TFs)存在显著的品种差异(P〈0.05),且富集系数均大于1.0。当土壤Cd浓度超过0.5mg·kg。时,芦蒿茎中Cd含量均超过无公害蔬菜安全要求,说明该土壤已不适宜种植芦蒿,当土壤Cd含量略高于自然背景值时,则可以选择伏秋芦蒿。 相似文献
230.
茉莉花茶品质形成机理研究进展 总被引:1,自引:0,他引:1
“茶引花香以益茶味”。茉莉花茶是我国生产历史较为悠久的特种茶之一,以清新的花香和醇爽的滋味深受广大消费者的青睐。 相似文献