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排序方式: 共有508条查询结果,搜索用时 15 毫秒
31.
Patrícia Castro Monteiro Maria Inês Braga de Oliveira Franmir Rodrigues Brando Caio Francisco Santana Farias Cludia Majolo Francisco Clio Maia Chaves Humberto Ribeiro Bizzo Fernanda Loureiro de Almeida OSullivan Maurício Latera Martins Edsandra Campos Chagas 《Aquaculture Research》2022,53(1):265-275
This study evaluated the effect of short-term baths with the essential oils (EOs) of Lippia sidoides, Ocimum gratissimum and Zingiber officinale on the survival, haematological, biochemical and histopathological parameters of native fish tambaqui (Colossoma macropomum), challenged with Aeromonas hydrophila. After challenge, the fish infected with A. hydrophila received therapeutic baths of 60 min, for five consecutive days. Treatments were as follows: challenged and not treated; challenged and treated with 10 mg L?1 of gentamicin; challenged and treated with EO of L. sidoides (2.5 and 5.0 mg L?1); challenged and treated with EO of O. gratissimum (5.0 and 10.0 mg L?1); challenged and treated with Z. officinale EO (5.0 and 10.0 mg L?1). The highest survival rates were 89.5% (fish treated with 5.0 mg L?1 of O. gratissimum EO) and 75.0% (fish treated with 5.0 mg L?1 of L. sidoides EO). Reductions in the haematocrit percentage, haemoglobin and erythrocyte number were observed in fish treated with L. sidoides and Z. officinale EOs compared with control fish. Mild to moderate damage to the liver tissue of fish after challenge and EO treatments were observed. It is suggested that baths containing O. gratissimum and L. sidoides EOs consist in a viable treatment to increase survival rates of C. macropomum infected with A. hydrophila. 相似文献
32.
Stephen Joslyn Suzanna Richards Susanne Boroffka Mark Mitchell Gawain Hammond Martin Sullivan 《Veterinary radiology & ultrasound》2014,55(1):63-67
Enhancement of extra‐ocular muscles has been reported in cases of orbital pathology in both veterinary and medical magnetic resonance imaging. We have also observed this finding in the absence of orbital disease. The purpose of this retrospective study was to describe extra‐ocular muscle contrast enhancement characteristics in a group of dogs with no known orbital disease. Magnetic resonance images (MRI) from dogs with no clinical evidence of orbital disease and a reportedly normal MRI study were retrieved and reviewed. Contrast enhancement percentages of the medial, lateral, ventral, and dorsal rectus muscles were calculated based on signal‐to‐noise ratios that were in turn determined from hand‐traced regions of interest in precontrast, immediate postcontrast and 10‐min postcontrast scans. Comparison measurements were made in the pterygoid muscle. Contrast enhancement of the extra‐ocular muscles was observed in all patients (median contrast enhancement percentage 45.0%) and was greater than that of pterygoid muscle (median contrast enhancement percentage 22.7%). Enhancement of the extra‐ocular muscles persisted 10 min after contrast administration (median contrast enhancement percentage 43.4%). Findings indicated that MRI contrast enhancement of extra‐ocular muscles is likely normal in dogs. 相似文献
33.
N. Hiramatsu A. Hara T. Matsubara K. Hiramatsu C.V. Sullivan 《Fish physiology and biochemistry》2003,28(1-4):301-303
A full-length cDNA encoding a vitellogenin (Vg) receptor (VgR) was isolated and sequenced from a white perch, Morone americana, ovarian cDNA library. The perch expresses a single VgR that is structurally classified as an LR8 type (without an 0-linked sugar domain) and appears to be the only species observed to possess no splice variant of the receptor. We proposed a hypothetical model for ovarian lipid transfer in Morone species, one in which the `single VgR' transports Vg and other lipoproteins via a selective endocytotic pathway based on ligand affinity, in conjunction with a lipase-mediated pathway of fatty acid transport. 相似文献
34.
Susan P. Crowley Fergal O’Gara Orla O’Sullivan Paul D. Cotter Alan D. W. Dobson 《Marine drugs》2014,12(12):5916-5929
Antibiotic resistance among pathogenic microorganisms is becoming ever more common. Unfortunately, the development of new antibiotics which may combat resistance has decreased. Recently, however the oceans and the marine animals that reside there have received increased attention as a potential source for natural product discovery. Many marine eukaryotes interact and form close associations with microorganisms that inhabit their surfaces, many of which can inhibit the attachment, growth or survival of competitor species. It is the bioactive compounds responsible for the inhibition that is of interest to researchers on the hunt for novel bioactives. The genus Pseudovibrio has been repeatedly identified from the bacterial communities isolated from marine surfaces. In addition, antimicrobial activity assays have demonstrated significant antimicrobial producing capabilities throughout the genus. This review will describe the potency, spectrum and possible novelty of the compounds produced by these bacteria, while highlighting the capacity for this genus to produce natural antimicrobial compounds which could be employed to control undesirable bacteria in the healthcare and food production sectors. 相似文献
35.
36.
Nora S Matthews DVM Dip ACVA Tex S Taylor DVM Dip ACVS & Jennifer A Sullivan DVM 《Veterinary anaesthesia and analgesia》2002,29(1):36-42
Objective To compare three combinations of injectable anesthetics in miniature donkeys for quality of induction, recovery, muscle relaxation, cardiopulmonary changes during anesthesia and duration of recumbency. Design Prospective, randomized experimental study. Animals Six miniature donkeys (< 90 cm in height at the withers) weighing 92–127 kg were used. Materials and methods The drug combinations were: xylazine?butorphanol?ketamine (XBK), xylazine?butorphanol?tiletamine?zolazepam (XBT) and xylazine?propofol (XP). Each miniature donkey was anesthetized with each combination at 1‐week intervals in random order. Heart and respiratory rates, indirect blood pressure and temperature were measured before and at 5‐minute intervals during recumbency. Arterial blood samples were drawn for blood‐gas analysis before and at 5, 15 and 30 minutes of anesthesia when samples could be collected. Recumbency time to sternal and time to standing were recorded and a subjective evaluation of induction, muscle relaxation and recovery were made. Results Mean recumbency time ± SD was 14.7 ± 9.4, 33.8 ± 6.3 and 14.6 ± 1.9 minutes with XBK, XBT and XP, respectively. Mean time to standing ± SD was 28.4 ± 11.3, 43.7 ± 7.2 and 26.3 ± 2.9 minutes with XBK, XBT and XP, respectively. Heart and respiratory rates and blood pressures varied from baseline but were always within normal ranges. Hemoglobin saturation, pH and PaO2 tended to be lower with these doses of XBT and XP. Conclusions and clinical relevance Overall quality of anesthesia was poor with XBK. At the doses used this combination did not provide sufficient anesthesia compared with the combinations of XBT and XP, which appeared to provide acceptable anesthesia of short duration in miniature donkeys. 相似文献
37.
38.
T. J. Sullivan B. J. Cosby A. T. Herlihy C. T. Driscoll I. J. Fernandez T. C. McDonnell C. W. Boylen S. A. Nierzwicki-Bauer K. U. Snyder 《Water, air, and soil pollution》2007,185(1-4):279-291
Many lakes in the Adirondack Mountains, New York, have acidified over the past century due to acidic atmospheric deposition. More recently, most monitored lakes have shown signs of chemical recovery (increase in acid neutralizing capacity) as sulfur deposition levels have declined in response to the Clean Air Act and other emissions control legislation. We used measured and modeled trends in past lakewater acidification and projections of future recovery from acidification to extrapolate results from judgment samples of intensively studied lakes to the population of acid-sensitive Adirondack lakes. Simulations were developed for 70 watersheds using the Model of Acidification of Groundwater in Catchments (MAGIC) to classify lakes according to their sensitivity to change in atmospheric S and N deposition. MAGIC simulations suggested that the modeled Adirondack Long-Term Monitoring Project (ALTM) and Adirondack Effects Assessment Project (AEAP) lakes were largely among the lakes in the population that had acidified most between 1850 and 1990. Most of the modeled ALTM/AEAP lakes were within the top 36% of acid sensitivity, based on model projections of past acidification and future chemical recovery, compared with the 1,829 Adirondack lakes in EPA’s Environmental Monitoring and Assessment Program (EMAP) statistical frame. Results of this research will allow fuller utilization of data from on-going chemical and biological monitoring and process-level studies by providing a basis for regionalization of findings and developing/refining relationships among watershed characteristics, chemical change, and biological responses to changing levels of acidic deposition. 相似文献
39.
T. J. Sullivan J. R. Webb K. U. Snyder A. T. Herlihy B. J. Cosby 《Water, air, and soil pollution》2007,182(1-4):57-71
A geologic classification scheme was combined with elevation to test hypotheses regarding watershed sensitivity to acidic deposition using available regional spatial data and to delimit a high-interest area for streamwater acidification sensitivity within the Southern Appalachian Mountains region. It covered only 28% of the region, and yet included almost all known streams that have low acid neutralizing capacity (ANC ≤20 μeq l?1) or that are acidic (ANC ≤0). The five-class geologic classification scheme was developed based on recent lithologic maps and streamwater chemistry data for 909 sites. The vast majority of the sampled streams that had ANC ≤20 μeq l?1 and that were totally underlainby a single geologic sensitivity class occurred in the siliceous class, which is represented by such lithologies as sandstone and quartzite. Streamwater acid-base chemistry throughout the region was also found to be associated with a number of watershed features that were mapped for the entire region, in addition to lithology and elevation, including ecoregion, physiographic province, soils type, forest type and watershed area. Logistic regression was used to model the presence/absence of acid-sensitive streams throughout the region. 相似文献
40.
Heparin affinity: purification of a tumor-derived capillary endothelial cell growth factor 总被引:73,自引:0,他引:73
Y Shing J Folkman R Sullivan C Butterfield J Murray M Klagsbrun 《Science (New York, N.Y.)》1984,223(4642):1296-1299
A tumor-derived growth factor that stimulates the proliferation of capillary endothelial cells has a very strong affinity for heparin. This heparin affinity makes it possible to purify the growth factor to a single-band preparation in a rapid two-step procedure. The purified growth factor is a cationic polypeptide, has a molecular weight of about 18,000, and stimulates capillary endothelial cell proliferation at a concentration of about 1 nanogram per milliliter. 相似文献