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81.
Wholegrain consumption is associated with several health benefits, in contrast to the consumption of refined grains. This can partly be related to the antioxidant compounds in the outer parts of the grain kernel. The bioaccessibility of these antioxidant compounds from the wholegrain matrix during gastrointestinal digestion is crucial for their absorption and bioavailability. In the current study, the bioaccessible compounds from aleurone, bran and flour were obtained from a dynamic in vitro model of the upper gastrointestinal tract. They were collected at 1 h time intervals to assess their antioxidant capacity (TEAC assay) and also their anti-inflammatory effect (TNF-α reduction in U937 macrophages stimulated with LPS). The bioaccessible compounds from aleurone had the highest antioxidant capacity and provided a prolonged anti-inflammatory effect, shown by the TNF-α reduction of a relatively late time-interval (3–4 h after start of digestion). The contribution of ferulic acid to those effects was minor due to its low bioaccessibility. Aleurone seems a promising wheat fraction for cereal products with a healthy added value. 相似文献
82.
Population genetic structure of common bottlenose dolphins (Tursiops truncatus) in the Adriatic Sea and contiguous regions: implications for international conservation 下载免费PDF全文
Stefania Gaspari Draško Holcer Peter Mackelworth Caterina Fortuna Alexandros Frantzis Tilen Genov Morgana Vighi Chiara Natali Nikolina Rako Elisa Banchi Guido Chelazzi Claudio Ciofi 《水产资源保护:海洋与淡水生态系统》2015,25(2):212-222
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83.
Chao‐Xi Luo Meng‐Jun Hu Xin Jin Liang‐Fen Yin Patricia K Bryson Guido Schnabel 《Pest management science》2010,66(12):1308-1315
BACKGROUND: The cytochrome b (Cyt b) gene is a key genetic determinant for quinone outside inhibitor (QoI) fungicide resistance in plant pathogenic fungi. A mutation at amino acid position G143 can cause qualitative resistance unless it is part of the recognition site for a self‐splicing intron. The objective of this study was to clone and sequence the Cyt b gene from Monilinia fructicola (Wint.) Honey, the causal agent of brown rot of stone fruits, and to assess the risk for the development of a mutation at position 143. RESULTS: The Cyt b gene of M. fructicola was 11 927 bp in size and contained seven introns located at cDNA positions (5′–3′) 204, 395, 430, 491, 507, 780 and 812 with sizes of 1592, 1318, 1166, 1252, 1065, 2131 and 2227 bp respectively. Sequence analysis revealed that the above‐mentioned 1166 bp intron, a self‐splicing group I intron, was located just downstream of the G143 codon. The Cyt b gene region covering the G143 location and the adjacent 1166 bp intron was PCR amplified and sequenced from Chinese and US isolates, indicating that the intron may be omnipresent in M. fructicola. CONCLUSION: This is the first complete Cyt b gene sequence published for M. fructicola or any other Monilinia species, forming the basis for molecular analysis of QoI fungicide resistance. Sequence analysis revealed that the G143A mutation responsible for high levels of QoI fungicide resistance in many plant pathogenic fungi may not develop in M. fructicola unless genotypes emerge that lack the 1166 bp intron. Copyright © 2010 Society of Chemical Industry 相似文献
84.
Jan Bronders Ilse Van Keer Kaatje Touchant Guido Vanermen Daniel Wilczek 《Journal of Soils and Sediments》2009,9(1):74-82
Background, aim, and scope
The membrane interphase probe (MIP?) from Geoprobe Systems® has frequently been applied in different countries for the characterization of soil contaminated with volatile organic carbons (VOCs). Experience shows that misinterpretation of the collected data is common. This is mainly due to the lack of understanding and knowledge related to the detectors used, their detection limits, and the sensitivity of the MIP system. It has been noticed that the sensitivity of the system given by the producer and by different users are rather optimistic, e.g., the values given are lower (= better) than those actually experienced in the field. A need for a better understanding of the MIP system sensitivity, combined with a more scientifically based interpretation of the collected data, exists.Materials and method
Both laboratory tests (using solutions) as well as field measurements were carried out using different detector configurations to allow a better interpretation of the detector signals/system sensitivity and to collect qualitative information. These configurations were: (1) detectors stand alone; (2) the use of a 2-ml sample loop, and (3) a purge and trap system. The configurations (2) and (3) are used in combination with a capillary column to carry out on-site qualitative and semiquantitative analyses.Results and discussion
With respect to the configuration of “detectors stand alone,” detection limits for toluene (in aqueous solutions) range between 4 ppm (flame ionization detector—FID) and 10 ppm [photo ionization detector (PID)]. For chlorinated aliphatic hydrocarbons (CAHs), observed limits are 10 ppm (FID), 4–50 ppm (PID), and 3–10 ppm [dry electrolytic conductivity detector (DELCD)]. When using the 2-ml sample loop, relatively high concentrations have to be initially present in the soil. Observed detection limits for mono-aromatic hydrocarbons are 5–100 ppm; for CAHs, 1–50 ppm; for alkanes, 250–400 ppm; and for MTBE, 25 ppm. The application of purge and trap results in a better resolution and the detection of lower concentrations. Consequently, a better identification of the pollution with depth is possible. In this case, the detection limits are a function of the concentrations and the flushing time. In relation to the qualitative analyses, it was found that the configuration of the MIP-system with the built-in capillary column and the 2-ml sample loop or the purge and trap preconcentrator, respectively, are useful to carry out on-site analyses, thus allowing a better identification of the pollution in a vertical profile.Conclusions
The measurements carried out using the MIP with detectors stand-alone or in combination with a loop or trap, or connected to a column, confirm that analysis is indeed very useful to characterize VOC source zones when knowing and understanding its performance. This relates mainly to the detection limits of the MIP system. For a selection of parameters, such limits have been obtained. These values seem to be more realistic than those found in the few references where numbers are given. For the qualitative measurements, it can be concluded that a better resolution is obtained, and pollutants present in lower concentrations will be detected when using the purge and trap. It is advised to determine the optimal flushing time and the detection limit of the expected pollutants in advance.Recommendations and perspectives
This study indicates that there is still a need for further measurements and discussion between users. Finally, additional data should result in a better interpretation of the collected field data. 相似文献85.
Ferrini AM Mannoni V Carpico G Pellegrini GE 《Journal of agricultural and food chemistry》2008,56(3):784-788
A novel application of a hybrid biosensor is here employed as an analytical method for the detection and presumptive identification of beta-lactam residues in milk. The method is based on measurements of carbon dioxide (CO2), the production of which is related to the microbial growth of the test microorganism Bacillus stearothermophilus var. calidolactis. The presence of beta-lactams in milk inhibits microbial growth and, consequently, the CO2 production rate. The analysis is based on the variation of CO2 between a milk sample spiked with beta-lactams and a twin milk sample containing beta-lactams plus a broad spectrum beta-lactamase, using an electrochemical device of biosensor. A blank milk sample is included as control. The result is obtained starting from the first 120 min. Moreover, the ability to recognize all of the beta-lactams speeds the total time of analysis when chemical identification and quantification are required. The analytical method appears to be adequate for milk control for qualitative screening purposes, complying with the requirements stated in Decision 2002/657/EC. 相似文献
86.
87.
Storage and stability of organic matter and fossil carbon in a Luvisol and Phaeozem with continuous maize cropping: A synthesis 总被引:1,自引:0,他引:1
Heiner Flessa Wulf Amelung Mirjam Helfrich Guido L. B. Wiesenberg Gerd Gleixner Sonja Brodowski Janet Rethemeyer Christiane Kramer Pieter M. Grootes 《植物养料与土壤学杂志》2008,171(1):36-51
Quantitative information about the amount and stability of organic carbon (OC) in different soil organic‐matter (OM) fractions and in specific organic compounds and compound‐classes is needed to improve our understanding of organic‐matter sequestration in soils. In the present paper, we summarize and integrate results performed on two different arable soils with continuous maize cropping (a) Stagnic Luvisol with maize cropping for 24 y, b) Luvic Phaeozem with maize cropping for 39 y) to identify (1) the storage of OC in different soil organic‐matter fractions, (2) the function of these fractions with respect to soil‐OC stabilization, (3) the importance and partitioning of fossil‐C deposits, and (4) the rates of soil‐OC stabilization as assessed by compound‐specific isotope analyses. The fractionation procedures included particle‐size fractionation, density fractionation, aggregate fractionation, acid hydrolysis, different oxidation procedures, isolation of extractable lipids and phospholipid fatty acids, pyrolysis, and the determination of black C. Stability of OC was determined by 13C and 14C analyses. The main inputs of OC were plant litter (both sites) and deposition of fossil C likely from coal combustion and lignite dust (only Phaeozem). 相似文献
88.
Elizabeth R. Carvalho Tatiana Champion Francielli Ambrosini Gabrieli A. da Silva Gabrielle C. Freitas Ricardo G. D’Otaviano de Castro Vilani 《Veterinary anaesthesia and analgesia》2019,46(1):43-54
Objective
To investigate the effects of a low dose of dexmedetomidine (DEX) followed by constant rate infusion (CRI) and reversal with atipamezole on systolic and diastolic functions in isoflurane-anesthetized healthy cats.Study design
Prospective cohort study.Animals
A group of 11 client-owned adult cats.Methods
Baseline transthoracic echocardiography (TTE) was performed, followed by intramuscular (IM) administration of DEX (5 μg kg?1). After 10 minutes, sedation was scored, adverse effects were recorded and another TTE performed. Approximately 40 minutes after DEX administration, anesthesia was induced by isoflurane mask and maintained with 1.2% end-tidal isoflurane and DEX CRI (1 μg kg?1 hour?1) for 80 minutes. Physiological variables were recorded every 10 minutes, and TTE was repeated 10, 30 and 60 minutes after the start of anesthesia. CRI was stopped, atipamezole (30 μg kg?1) was administered IM and a final TTE was performed after 10 minutes. Repeated measures over time were submitted to one-way analysis of variance or Kruskal–Wallis test according to data distribution; significance was assumed at p < 0.05.Results
After DEX premedication, mild sedation and a slight but significant increase in systolic arterial pressure occurred, and vomiting was a common adverse effect. The cardiac output (CO) and heart rate decreased during anesthesia, with no changes after administration of atipamezole. Trivial valvular insufficiencies were commonly seen after DEX premedication and during CRI. Myocardial radial and longitudinal systolic functions were not affected by sedation or by anesthesia. The late phase of diastole on both right and left ventricles was affected by isoflurane–DEX CRI. Global left ventricular myocardial performance was not impaired.Conclusions
and clinical relevance Decreased CO and late diastolic impairment were observed in healthy cats administered a low dose of DEX for premedication followed by anesthesia with isoflurane and DEX CRI. 相似文献89.
The effect of the whole methanol extracts of five Chrysanthemum species on feeding and performance of Spodoptera littoralis (Boisduval) larvae has been investigated in vitro. The extracts exhibited an anti-feeding and phagostimulating activities against cotton leafworm larvae when applied either on leaf discs or incorporated into an artificial diet. Under chosen conditions, the antifeedant index calculated over 24 h for sixth instar larvae significantly varied from 78.55 for Chrysanthemum segetum L. to −44.18 for Chrysanthemum fuscatum Desf. at the dose of 1000 ppm. Toxicity of the extracts was manifested by a high mortality, reduced growth rates, and low weight gain by larvae fed on diets containing 1000–10,000 ppm of the extract. Anyone of the larvae treated with Chrysanthemum macrotum (D.R.) Ball. leaves crude extract survived to pupation at the two higher concentrations. The time to pupation increased for Chrysanthemum grandiflorum flowers crude extract from 11.40 ± 0.93 to 28.93 ± 10.92 days as the extract concentration in the diet increased from 0 to 10,000 ppm. The ingestion of crude extract by the third instar larvae reduced significantly the consumption, growth and utilisation of the ingested and digested food, and reduced digestibility. 相似文献
90.
Morello E Martano M Squassino C Iussich S Caccamo R Sammartano F Zabarino S Bellino C Pisani G Buracco P 《Veterinary surgery : VS》2008,37(5):420-426
Objective— To evaluate outcome after transanal rectal pull-through amputation of single colorectal adenocarcinoma and in situ carcinoma (T is ) in dogs.
Study Design— Retrospective case series.
Animals— Dogs (n=11) with colorectal cancer.
Methods— Full-thickness colorectal amputation by either simple transanal (7 dogs) or combined abdominal–transanal (4) pull-through technique.
Results— Adenocarcinoma (8) and T is (2) were removed with 3–6 cm of grossly normal tissue, cranial and caudal to the tumor, or in 1 T is with 2 cm grossly normal tissue, cranial and caudal. Two dogs that had a combined abdominal–transanal approach died within 4 days. In the other dogs, postoperative complications included short-term tenesmus (6 dogs), rectal bleeding (11), rectal stricture (3), and long-term fecal incontinence (1). Postoperative recurrence and metastatic rates for adenocarcinoma were 18.2% and 0%, respectively. Median disease-free interval and survival time were not reached. Mean disease-free and overall survival times were 44.3 and 44.6 months (range, 0–75 months), respectively.
Conclusion— En bloc excision of colorectal T is and adenocarcinoma may be followed by a long survival. Complications of the transanal approach are usually moderate and self-limiting, but complications are more common and severe when more extensive resections are performed through a combined abdominal–transanal approach.
Clinical Relevance— Transanal rectal pull-through amputation is suitable for en bloc resection of colorectal neoplasia. A combined abdominal–transanal approach should be reserved for tumors extending from the mid-cranial region of the rectum to the descending colon. 相似文献
Study Design— Retrospective case series.
Animals— Dogs (n=11) with colorectal cancer.
Methods— Full-thickness colorectal amputation by either simple transanal (7 dogs) or combined abdominal–transanal (4) pull-through technique.
Results— Adenocarcinoma (8) and T is (2) were removed with 3–6 cm of grossly normal tissue, cranial and caudal to the tumor, or in 1 T is with 2 cm grossly normal tissue, cranial and caudal. Two dogs that had a combined abdominal–transanal approach died within 4 days. In the other dogs, postoperative complications included short-term tenesmus (6 dogs), rectal bleeding (11), rectal stricture (3), and long-term fecal incontinence (1). Postoperative recurrence and metastatic rates for adenocarcinoma were 18.2% and 0%, respectively. Median disease-free interval and survival time were not reached. Mean disease-free and overall survival times were 44.3 and 44.6 months (range, 0–75 months), respectively.
Conclusion— En bloc excision of colorectal T is and adenocarcinoma may be followed by a long survival. Complications of the transanal approach are usually moderate and self-limiting, but complications are more common and severe when more extensive resections are performed through a combined abdominal–transanal approach.
Clinical Relevance— Transanal rectal pull-through amputation is suitable for en bloc resection of colorectal neoplasia. A combined abdominal–transanal approach should be reserved for tumors extending from the mid-cranial region of the rectum to the descending colon. 相似文献