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511.
512.
Controlled reproduction in the wild European eel (Anguilla anguilla): two populations compared 总被引:1,自引:0,他引:1
Oliviero Mordenti Andrea Di Biase Giuseppe Bastone Rubina Sirri Annalisa Zaccaroni Albamaria Parmeggiani 《Aquaculture International》2013,21(5):1045-1063
This study aimed to describe the response variability of female silver eels in terms of gonad development and eggs production to a standardized gonadotropic treatment (Carp pituitary extracts—CPE), and to relate this variability to population characteristics. For this purpose, sexual maturation, ovulation, and fertilization were induced in two eel populations coming from different locations in Adriatic Sea (Comacchio—CM and Marano-Grado—MG lagoons), and after that, their reproductive capacity was valuated. External (Silver index—SI, Eye index—EI, Pectoral fin length index—PFLI, Condition factor—K) and hormonal (17β-estradiol—E2, testosterone—T) parameters were measured, and some subject/group were killed for histological and lipid analysis and age determination. Morphometric parameters showed the CM-Group to have highest values of Body weight (BW), Body length (BL), and K, while MG-Group presented highest PFLI and Gonadosomatic index (GSI) values. Regarding hormonal analysis, the CM-Group showed significantly higher T and E2 levels than the MG-Group, both groups showed considerably rapid increase at T5 (5th injection). A positive trend in gonadal development was found through histological evaluation; a more regular maturation was observed in the MG-Group, whereas the CM-Group presented an exponential oocytes development starting from T10 (10th week), which led to an anticipated spawning. Lipid content showed significant differences in T0 (start study), post-ovulation, and Control (30th week) between CM and MG eels. As to zootechnical performances, while MG eels released spontaneously into the water, the CMs were stripped in order to check ovulation. The MG eels were statistically the most productive with 40.1 ± 6.33 % BW of eggs released. Furthermore, CM females ovulated mainly between the 19th and 22nd week (77.8 % spawned eels) instead in the MG’s ovulation goes from the 24th to the 28th week (100 % spawned eels). As fertilization is of concern, in both groups fertilized eggs were obtained with no difference in larvae production. These results seem to indicate that bigger dimensions, higher K, and larger lipid content (Comacchio eels) could fasten gonadic maturation without positively influencing reproductive performance of animals, both in term of quantity and quality of produced eggs. Smaller females with a highest SI (Marano-Grado eels) presented a more regular gonadic development, leading the animals to spontaneous spawning. 相似文献
513.
Valentina Sepe Raffaella Ummarino Maria Valeria D��Auria Orazio Taglialatela-Scafati Simona De Marino Claudio D��Amore Barbara Renga Maria Giovanna Chini Giuseppe Bifulco Yoichi Nakao Nobuhiro Fusetani Stefano Fiorucci Angela Zampella 《Marine drugs》2012,10(11):2448-2466
Using theonellasterol as a novel FXR antagonist hit, we prepared a series of semi-synthetic derivatives in order to gain insight into the structural requirements for exhibiting antagonistic activity. These derivatives are characterized by modification at the exocyclic carbon-carbon double bond at C-4 and at the hydroxyl group at C-3 and were prepared from theonellasterol using simple reactions. Pharmacological investigation showed that the introduction of a hydroxyl group at C-4 as well as the oxidation at C-3 with or without concomitant modification at the exomethylene functionality preserve the ability of theonellasterol to inhibit FXR transactivation caused by CDCA. Docking analysis showed that the placement of these molecules in the FXR-LBD is well stabilized when on ring A functional groups, able to form hydrogen bonds and π interactions, are present. 相似文献
514.
Germana Esposito Roberta Teta Roberta Miceli Luca S. Ceccarelli Gerardo Della Sala Rosa Camerlingo Elena Irollo Alfonso Mangoni Giuseppe Pirozzi Valeria Costantino 《Marine drugs》2015,13(1):444-459
The study of the secondary metabolites contained in the organic extract of Caribbean sponge Smenospongia aurea led to the isolation of smenothiazole A (3) and B (4), hybrid peptide/polyketide compounds. Assays performed using four solid tumor cell lines showed that smenothiazoles exert a potent cytotoxic activity at nanomolar levels, with selectivity over ovarian cancer cells and a pro-apoptotic mechanism. 相似文献
515.
516.
Giuseppe Firrao Emanuela Torelli Emanuela Gobbi Steluta Raranciuc Gianluca Bianchi Romano Locci 《Journal of Cereal Science》2010
Mycotoxin contamination is a major concern to the maize industry worldwide. Despite the several strategies that have been exploited in an attempt to reduce the severity of this problem, during conducive years, severely contaminated lots are still introduced in the maize processing chain affecting the general quality and safety of the product. As chemical analysis is laborious, time consuming and equipment dependent, more convenient methods are needed for the early identification of contaminated lots. Here a novel approach based on image analysis that provides fast response with minimal equipment and effort is presented. Maize samples were grounded and imaged under 10 different LED lights with emission centered at wavelengths ranging from 720 to 940 nm. The digital images were converted into matrices of data to compute comparative indexes. A three layers feed-forward neural network was trained to predict mycotoxin content from the calculated indexes. The results showed a significant correlation between predictions from image analysis and the concentration of the mycotoxin fumonisin as determined by chemical analysis. The technique developed produces reliable contamination estimates within few minutes and can be readily used to assist lot selection in various steps of the maize processing chain. 相似文献
517.
Giuseppe Piccione Stefania Casella Claudia Giannetto Elisabetta Giudice 《Journal of veterinary science (Suw?n-si, Korea)》2010,11(2):121-124
The present study was to assess the effect of storage conditions on prothrombin time (PT), activated partial thromboplastin time (aPTT) and fibrinogen concentration in blood samples of healthy dogs. Thirty-five dogs of various breeds were included in the study. Citrated blood samples were obtained and plasma was divided into four aliquots to assess selected clotting parameters by means of a coagulometer. The first aliquot was analysed within 1 h after collection, while the remaining 3 were stored at 8℃ for 4, 8 and 24 h, respectively. One-way repeated measures analysis of variance documented a significant decreasing effect on PT at 24 h compared to 8 h and on fibrinogen concentration after 8 and 24 h compared to sampling time and at 4 and 24 h compared to 8 h post sampling. In conclusion, the results of this study indicate that only fibrinogen appears prone to significant decrease. In fact, aPTT is not substantially affected by refrigeration for at least 24 h post sampling and PT showed a statistical difference that does not necessary indicate biological significance as the results obtained were within reference intervals for the dog. 相似文献
518.
Massimo MORGANTE Matteo GIANESELLA Elisabetta VERSACE Laura CONTALBRIGO Stefania CASELLA Chiara CANNIZZO Giuseppe PICCIONE Calogero STELLETTA 《Animal Science Journal》2010,81(6):722-730
To evaluate the metabolic profile of pregnant and non‐pregnant ewes with high or low degree of behavioral lateralization, we used 57 clinically healthy Sardinian ewes. They were divided into three groups: Group A (nonpregnant ewes), Group B (pregnant ewes with one fetus) and Group C (pregnant ewes with twin fetuses). Using behavioral tests, in all groups lateralization was established and ewes were distinguished into ewes with high and low level of lateralization. Every 30 days for 4 months (at 35, 76, 103 and 145 days of gestation), blood samples were collected and total cholesterol, triglycerides, nonesterified fatty acids (NEFA), glucose, insulin, creatinine, urea, uric acid, total protein, total bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), γ‐glutamine transferase (γ‐GT), β‐hydroxybutyrate (β‐OHB), chloride (Cl), potassium (K), sodium (Na) and calcium (Ca) were assessed. The repeated measures multifactor analysis of variance (MANOVA) showed statistical differences of time, pregnancy and degree of lateralization on some studied parameters. These results confirm that pregnancy represents a very important metabolic moment and show the effect of the degree of behavioral lateralization on the assessment of metabolic parameters in non‐pregnant and pregnant ewes. Further studies are necessary to value the influence of these factors on other parameters such as hematological parameters and hormones. 相似文献
519.
Donald A. Croll Heidi Dewar Nicholas K. Dulvy Daniel Fernando Malcolm P. Francis Felipe Galván‐Magaña Martin Hall Shawn Heinrichs Andrea Marshall Douglas Mccauley Kelly M. Newton Giuseppe Notarbartolo‐Di‐Sciara Mary O'Malley John O'Sullivan Marloes Poortvliet Marlon Roman Guy Stevens Bernie R. Tershy William T. White 《水产资源保护:海洋与淡水生态系统》2016,26(3):562-575
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520.
Quintavalla C Bossolini E Rubini G Tursi M 《Journal of the American Animal Hospital Association》2010,46(6):444-448
A 2-year-old, neutered male, domestic shorthair cat was presented for investigation of dyspnea and episodic weakness. Clinical and ultrasonographic features were consistent with right ventricular cardiomyopathy. Pathological findings documented Uhl's anomaly. Although rare, Uhl's anomaly should be a differential diagnosis for cats with right-sided congestive heart failure. In particular, Uhl's anomaly could be misdiagnosed as arrhythmogenic right ventricular cardiomyopathy due to the similarity of clinical and echocardiographic findings. 相似文献