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991.
Valenzuela-Gutiérrez Rocío Lago-Lestón Asunción Vargas-Albores Francisco Cicala Francesco Martínez-Porchas Marcel 《Fish physiology and biochemistry》2021,47(4):1179-1198
Fish Physiology and Biochemistry - The aquaculture industry’s rapid growth to meet commercial demand can trigger an outbreak of infectious diseases due to high-density farming. Antibiotic... 相似文献
992.
ngel Martín Ortiz‐Estrada Marcel Martínez‐Porchas Luis Rafael Martínez‐Crdova Francisco Vargas‐Albores Armando Burgos‐Hernandz Susana María Scheuren‐Acevedo Teresa Gollas‐Galvn 《Aquaculture Research》2021,52(1):334-344
Biofilm‐based aquaculture systems constitute a promising alternative for intensive shrimp rearing. Microorganisms forming biofilms can recycle the nitrogen compounds the production units improving the water quality while using zero or limited water exchange. This study aimed to compare the taxonomic profiles and the predicted functions related to the transformation of nitrogenous compounds between a heterotrophic‐ (HtB) and a probiotic biofilm (PrB), and the effect of these on the water quality and the productive response of cultured shrimp. Libraries of the 16S‐rRNA gene (V3‐V4 region) were prepared and sequenced to be used as a taxonomic biomarker. Analysis of metagenomic datasets revelated that genera Halomonas, Planctomycetes and Rhodopirellula were the most abundant genera in HtB; meanwhile, Bacillus, Halobacillus and Flavobacterium dominated in PrB. Regarding nitrogen metabolism, the proportion of genes encoding enzymes catalyzing the six pathways shaping the nitrogen metabolism showed differences between biofilms, which could also explain the difference in water quality between treatments. Concerning the productive response of shrimp, no significant differences were detected except for survival, which was higher in PrB. Finally, the results suggest that biofilms harbour functions for nitrogen metabolism, including dissimilatory nitrate reduction, assimilatory nitrate reduction, denitrification, nitrification, nitrogen fixation and anammox; however, the balance of these functional capabilities seems to be relevant to maintain water quality. 相似文献
993.
Vadoud H. Niri James B. Mathers Marcel F. Musteata Stan Lem Janusz Pawliszyn 《Water, air, and soil pollution》2009,204(1-4):205-213
All commercial gasoline fuels build up deposits on the spark plugs, injectors, oxygen sensors, catalytic converter, and inside the combustion chamber, which will lower the engine's performance and increase air pollution. As a result, fuel-based detergents have been developed to prevent and remove unwanted deposits. Unfortunately, many of the detergents use high amounts of aromatic solvents, which result in a greater risk of exposure to aromatic compounds like benzene. In this study, car exhaust was analyzed for benzene, toluene, ethylbenzene, and xylenes (BTEX), as well as formaldehyde and acetaldehyde during engine cleaning service using different chemical cleaners. A special device was designed for sampling from car exhaust using solid phase microextraction. The extracted compounds were analyzed using a gas chromatograph with flame ionization detector. The cleaning products were rated with regard to the amount of pollutants produced during the cleaning service. 相似文献
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996.
Nyman HT Nielsen OL McEvoy FJ Lee MH Martinussen T Hellmén E Kristensen AT 《American journal of veterinary research》2006,67(6):985-991
OBJECTIVE: To compare and correlate B-mode and color Doppler ultrasonographic characteristics with the histologic findings of benign and malignant mammary tumors in dogs. STUDY POPULATION: 49 mammary tumors in 26 dogs. PROCEDURES: Before excision, tumors were evaluated via B-mode and color Doppler ultrasonography to assess size, echogenicity, echopattern, acoustic transmission, invasiveness, and vascularity. Paraffin-embedded microsections of the tumors were stained with H&E and examined for presence of necrosis, cysts, cartilage, bone, mineralization, invasion of surrounding tissue, and tissue heterogeneity. To assess vascularity, the number and distribution of vessels that were stained by the Verhoeff van Gieson technique were recorded. RESULTS: Tumor echogenicity and echopattern on ultrasonographic images correlated with tissue heterogeneity detected histologically. Acoustic enhancement was correlated with the presence of necrotic or cystic areas. Tumor invasion into surrounding tissues as determined ultrasonographically did not correlate with the histologic findings. There was a significant correlation between the number of detected vessels and distribution of flow within the tumors determined via ultrasonographic and histologic examinations. CONCLUSIONS AND CLINICAL RELEVANCE: In canine mammary tumors, ultrasonographic characteristics appear to be correlated with histopathologic changes. Data suggest that ultrasonography may have an important role in the evaluation of mammary tumors in dogs, particularly in the evaluation of tissue composition and tumor vascularity. 相似文献
997.
Ross A Guénette SA Hélie P Vachon P 《The Canadian veterinary journal. La revue veterinaire canadienne》2006,47(11):1115-1117
Case of cutaneous necrosis in African Clawed frogs Xenopus laevis after the topical application of eugenol. African Clawed frogs showed necrotic cutaneous lesions after a topical application of high concentrations of eugenol, an analgesic and anesthetic agent. Microscopically, ulceration of the epidermis, a loss of mucous and serous glands as well as an infiltration of inflammatory cells were observed. 相似文献
998.
Ouellet M Dunn ME Lussier B Chailleux N Hélie P 《Journal of the American Animal Hospital Association》2006,42(6):467-471
An 11-year-old, castrated male Pomeranian was presented for intractable cough and dyspnea secondary to severe tracheal collapse. An endoluminal nitinol tracheal stent was placed with good results. Five months following placement of the prosthesis, clinical signs acutely recurred and failure of the implant was noted. A second stent was superimposed over the fractured stent and resulted in resolution of all clinical signs. The dog died several months later from progression of the tracheal collapse to the carina and mainstem bronchi. 相似文献
999.
Warren EH Vigneron NJ Gavin MA Coulie PG Stroobant V Dalet A Tykodi SS Xuereb SM Mito JK Riddell SR Van den Eynde BJ 《Science (New York, N.Y.)》2006,313(5792):1444-1447
CD8-positive T lymphocytes recognize peptides that are usually derived from the degradation of cellular proteins and are presented by class I molecules of the major histocompatibility complex. Here we describe a human minor histocompatibility antigen created by a polymorphism in the SP110 nuclear phosphoprotein gene. The antigenic peptide comprises two noncontiguous SP110 peptide segments spliced together in reverse order to that in which they occur in the predicted SP110 protein. The antigenic peptide could be produced in vitro by incubation of precursor peptides with highly purified 20S proteasomes. Cutting and splicing probably occur within the proteasome by transpeptidation. 相似文献
1000.
OBJECTIVE: To assess a laparoscopic technique for equine intestinal biopsy. STUDY DESIGN: Experimental study. ANIMALS: Seven adult horses. METHODS: Food but not water was withheld for 36 hours before laparoscopy. In 3 horses (group A) standing, right laparoscopic access to different small intestinal segments was compared with ventral median celiotomy access. Inaccessible segments were identified at necropsy. In 4 horses (group B), the feasibility of obtaining full-thickness duodenal and cecal biopsies and any associated morbidity were evaluated. Biopsy specimens were collected during standing right laparoscopy using a 2-step procedure and intracorporeal suturing technique, and abdominal lavage was performed. Horses were monitored clinically and by abdominal fluid cytology and microbial culture, and repeat laparoscopy was performed on day 6. RESULTS: Standing right flank laparoscopy provided good observation of small intestinal segments and enabled manipulation of all but 15-20 cm of the duodenum and approximately 40 cm more ileum compared with ventral median celiotomy. Group B horses had no complications, no adhesions, and no bacterial growth from peritoneal fluid samples. None of the horses had signs of abdominal pain. CONCLUSION: A 2-stage intestinal biopsy technique performed during standing, right flank laparoscopy may be a safe alternative to exploratory celiotomy and biopsy in normal horses. CLINICAL RELEVANCE: Right flank laparoscopy allows biopsy of intestinal segments including duodenum and 50% more of the ileum than is accessible by ventral median celiotomy. This technique should be evaluated in clinical patients. 相似文献