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41.
T Guimarães C Miranda M Pinto E Silva L Damásio AL Costa MJ Correia JC Duarte C Cosinha G Lopes G Thompson A Rocha 《Reproduction in domestic animals》2014,49(6):926-933
A possible role of breeding activities in the composition of the microbial population in stallions' external genitalia (EG) and the relationship between micro‐organisms colonizing the skin of the abdomen and the ones colonizing the EG have not been studied. In experiment 1, EG microbiological samples were collected from 41 stallions used for both natural cover and semen collection (BST) and from 18 non‐breeding stallions (NBST). A higher (p < 0.05) frequency of isolation of potentially pathogenic species was found for BST. Age did not influence number of micro‐organism species isolated both in BST and NBST. In experiment 2, the microbial content of the EG and semen was compared in 23 BST. Most micro‐organisms isolated from the EG were present in semen, albeit with a numerically lower prevalence. In 7 stallions, six microbial species isolated from semen were absent from the EG cultures, suggesting contamination by the operator. In experiment 3, a numerically higher number of micro‐organism species was isolated from the EG of 31 stallions, than from their skin of the ventral abdomen in contact with the penis or from the skin of the thorax. With the sole exception of Escherichia coli, potentially pathogenic bacteria were only isolated from the EG but not from the skin. Results suggest that breeding activity increased the number of species colonizing the EG; most species isolated from the EG were also found in semen even if with a lower frequency, and additional semen contamination seemed to occur during its manipulation. Many micro‐organism species of the skin were also isolated from the penis, but independently of being or not in contact with the penis, skin did not seem to provide an adequate environment for the growth of potentially pathogenic bacteria that were isolated from EG, with the sole exception for E. coli. 相似文献
42.
Adriano B Carregaro Gabrielle C Freitas Carlize Lopes Rafael Lukarsewski Fernanda S Tamiozzo Rogério R Santos 《Veterinary anaesthesia and analgesia》2014,41(2):205-211
ObjectiveTo evaluate the analgesic and physiological effects of epidural morphine administered at the sixth and seventh lumbar or the fifth and sixth thoracic vertebrae in dogs undergoing thoracotomy.Study designProspective, randomized, blinded trial.AnimalsFourteen mixed-breed dogs, weighing 8.6 ± 1.4 kg.MethodsThe animals received acepromazine (0.1 mg kg?1) IM and anesthesia was induced with propofol (4 mg kg?1) IV. The lumbosacral space was punctured and an epidural catheter was inserted up to the region between the sixth and seventh lumbar vertebrae (L, n = 6) or up to the fifth or sixth intercostal space (T, n = 8). The dogs were allowed to recover and after radiographic confirmation of correct catheter position, anesthesia was reinduced with propofol IV and maintained with 1.7% isoflurane. Following stabilization of monitored parameters, animals received morphine (0.1 mg kg?1) diluted in 0.9% NaCl to a final volume of 0.25 mL kg?1 via the epidural catheter, and after 40 minutes, thoracotomy was initiated. Heart rate and rhythm, systolic, mean and diastolic arterial pressures, respiratory rate, arterial hemoglobin oxygen saturation, partial pressure of expired CO2 and body temperature were measured immediately before the epidural administration of morphine (0 minute) and every 10 minutes during the anesthetic period. The Melbourne pain scale and the visual analog scale were used to assess post-operative pain. The evaluation began 3 hours after the epidural administration of morphine and occurred each hour until rescue analgesia.ResultsThere were no important variations in the physiological parameters during the anesthetic period. The post-operative analgesic period differed between the groups, being longer in T (9.9 ± 1.6 hours) compared with L (5.8 ± 0.8 hours).ConclusionsThe use of morphine, at a volume of 0.25 mL kg?1, administered epidurally over the thoracic vertebrae provided longer lasting analgesia than when deposited over the lumbar vertebrae.Clinical relevanceThe deposition of epidural morphine provided longer lasting analgesia when administered near to the innervation of the injured tissue without increasing side effects. 相似文献
43.
João H Perotta Paulo A Canola Maristela CS Lopes Patrícia M Évora Paulo EB Martinez André Escobar Carlos AA Valadão 《Veterinary anaesthesia and analgesia》2014,41(4):357-364
ObjectiveTo evaluate the effects of intravenous (IV) or intramuscular (IM) hyoscine premedication on physiologic variables following IV administration of medetomidine in horses.Study designRandomized, crossover experimental study.AnimalsEight healthy crossbred horses weighing 330 ± 39 kg and aged 7 ± 4 years.MethodsBaseline measurements of heart rate (HR), cardiac index (CI), respiratory rate, systemic vascular resistance (SVR), percentage of patients with second degree atrioventricular (2oAV) block, mean arterial pressure (MAP), pH, and arterial partial pressures of carbon dioxide (PaCO2) and oxygen (PaO2) were obtained 5 minutes before administration of IV hyoscine (0.14 mg kg?1; group HIV), IM hyoscine (0.3 mg kg?1; group HIM), or an equal volume of physiologic saline IV (group C). Five minutes later, medetomidine (7.5 μg kg?1) was administered IV and measurements were recorded at various time points for 130 minutes.ResultsMedetomidine induced bradycardia, 2oAV blocks and increased SVR immediately after administration, without significant changes in CI or MAP in C. Hyoscine administration induced tachycardia and hypertension, and decreased the percentage of 2oAV blocks induced by medetomidine. Peak HR and MAP were higher in HIV than HIM at 88 ± 18 beats minute?1 and 241 ± 37 mmHg versus 65 ± 16 beats minute?1 and 192 ± 38 mmHg, respectively. CI was increased significantly in HIV (p ≤ 0.05). Respiratory rate decreased significantly in all groups during the recording period. pH, PaCO2 and PaO2 were not significantly changed by administration of medetomidine with or without hyoscine.Conclusion and clinical relevanceHyoscine administered IV or IM before medetomidine in horses resulted in tachycardia and hypertension under the conditions of this study. The significance of these changes, and responses to other dose rates, requires further investigation. 相似文献
44.
Graciliana Lopes Georgios Daletos Peter Proksch Paula B. Andrade Patrícia Valent?o 《Marine drugs》2014,12(3):1406-1418
A monoacylglycerol (1) and a 1:1 mixture of two monogalactosyl diacylglycerols (MGDGs) (2 and 3) were isolated from the brown seaweed Fucus spiralis Linnaeus. The structures were elucidated by spectroscopic means (NMR and MS) and by comparison with the literature. Compound 1 was composed of a glycerol moiety linked to oleic acid (C18:1 Ω9). Compounds 2 and 3 contained a glycerol moiety linked to a galactose unit and eicosapentaenoic acid (C20:5 Ω3) combined with octadecatetraenoic acid (C18:4 Ω3) or linolenic acid (C18:3 Ω3), respectively. The isolated compounds were tested for their cytotoxic and anti-inflammatory activity in RAW 264.7 macrophage cells. All of them inhibited NO production at non-cytotoxic concentrations. The fraction consisting of compounds 2 and 3, in a ratio of 1:1, was slightly more effective than compound 1 (IC50 of 60.06 and 65.70 µg/mL, respectively). To our knowledge, this is the first report of these compounds from F. spiralis and on their anti-inflammatory capacity. 相似文献
45.
Laura de Andrade Moura Ana Carolina Marqui de Almeida Thaisa Francielle Souza Domingos Fredy Ortiz-Ramirez Diana Negr?o Cavalcanti Valéria Laneuville Teixeira André Lopes Fuly 《Marine drugs》2014,12(5):2471-2484
Cardiovascular diseases represent a major cause of disability and death worldwide. Therapeutics are available, but they often have unsatisfactory results and may produce side effects. Alternative treatments based on the use of natural products have been extensively investigated, because of their low toxicity and side effects. Marine organisms are prime candidates for such products, as they are sources of numerous and complex substances with ecological and pharmacological effects. In this work, we investigated, through in vitro experiments, the effects of three diterpenes (pachydictyol A, isopachydictyol A and dichotomanol) from the Brazilian marine alga, Dictyota menstrualis, on platelet aggregation and plasma coagulation. Results showed that dichotomanol inhibited ADP- or collagen-induced aggregation of platelet-rich plasma (PRP), but failed to inhibit washed platelets (WP). In contrast, pachydictyol A and isopachydictyol A failed to inhibit the aggregation of PRP, but inhibited WP aggregation induced by collagen or thrombin. These diterpenes also inhibited coagulation analyzed by the prothrombin time and activated partial thromboplastin time and on commercial fibrinogen. Moreover, diterpenes inhibited the catalytic activity of thrombin. Theoretical studies using the Osiris Property Explorer software showed that diterpenes have low theoretical toxicity profiles and a drug-score similar to commercial anticoagulant drugs. In conclusion, these diterpenes are promising candidates for use in anticoagulant therapy, and this study also highlights the biotechnological potential of oceans and the importance of bioprospecting to develop medicines. 相似文献
46.
Luciana Rossini Pinto Maria Lucia Carneiro Vieira Cláudio Lopes de Souza Jr Anete Pereira de Souza 《Euphytica》2003,134(3):277-286
BR-105 and BR-106 are important tropical maize populations, which were submitted to a high-intensity reciprocal recurrent
selection, generating the IG-3 and IG-4synthetics. Using 30-microsatellite loci,we measured and compared the genetic diversity
of these populations and their synthetics. The populations did not differ significantly regarding the amount of genetic diversity.
As a consequence of selection, genetic variability losses, in terms of mean number of alleles per locus,proportion of polymorphic
loci, and gene diversity did occur and were greater in the synthetic IG-3 than IG-4. In the synthetics, the number of loci
in adherence to Hardy-Weinberg proportions was superior to that observed in the populations. The Wright's mean fixation index
was higher than the mean value expected for outcrossing species (5%) indicating as light excess of homozygotic individuals
in both populations. The genetic distances confirmed the favourable effects of one cycle of recurrent selection, as the synthetics
became more isolated in comparison to the original populations.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
47.
The monomeric composition of suberin extracts obtained by gradual alkaline methanolysis of Quercus suber cork was determined by gas chromatography-mass spectrometry (GC-MS). Results show that 1-alkanols and alkanoic and alpha,omega-alkanedioic acids are preferentially removed upon mild alkaline conditions, whereas mid-chain-modified omega-hydroxyalkanoic acids are preferentially removed under stronger alkaline conditions. Saturated omega-hydroxyalkanoic acids are found to be abundant in all suberin extracts. These results are consistent with two distinct suberin fractions with different locations in cork cell walls and/or esterification degrees. It is proposed that these fractions correlate with the two main suberin peaks in the solid state (13)C NMR spectra of cork and suberin extracts. Quantitative GC-MS analysis showed that suberin monomers comprise approximately 30% (w/w) of the suberin extracts, the remaining comprising nonvolatile structures with high M(n) values, as measured by vapor pressure osmometry. The presence of a large fraction of high molecular weight aliphatic structures in suberin extracts is supported by the corresponding NMR spectra. 相似文献
48.
Celso Lopes de Albuquerque Frederico Denardi Adriana Cibele de Mesquita Dantas Rubens Onofre Nodari 《Euphytica》2011,181(2):277-284
Apple plants are self-incompatible because a genetic mechanism allows the female reproductive organ to recognize and reject
self-pollen or pollen from genetic related individuals and allows non-self pollen to effect fertilization. Thus, there are
implications to both breeding strategies and orchard management for fruit production. The purpose of this study was to identify
and to characterize the S-RNase alleles of the gametophytic incompatibility among apple cultivars developed in Brazil, seeking
to give support for choosing right combinations of parent in the apple breeding programs. It also sought to identify correct
combinations of scion/pollinator cultivars of commercial apple orchards. A total of 16 specific S-RNase alleles primers were
tested against DNA extracted from 12 Brazilian cultivars and their parents. The molecular analysis confronted to the reference
cultivars, showed that the cultivars Daiane, Imperatriz and Princesa have the same incompatibility S3 and S5 alleles, while
‘Lisgala’ showed the alleles S2 and S5; ‘Suprema’, S1 and S9; ‘Catarina’, S1 and S19; ‘Joaquina’ and ‘Fred Hough’, S5 and
S19; ‘Baronesa’, S3 and S9; ‘Duquesa’, S2 and S3. For ‘Primícia’ and ‘Condessa’ it was only possible to identify one of the
S-alleles, namely S24 and S2, respectively, with the second allele remaining to be identified. Progeny test indicated the
Mendelian inheritance for RNase alleles. Results of this study will be helpful to judiciously choose parents in apple breeding
programs to improve compatibility. 相似文献
49.
Comparative Earth History and Late Permian Mass Extinction 总被引:6,自引:0,他引:6
The repeated association during the late Neoproterozoic Era of large carbon-isotopic excursions, continental glaciation, and stratigraphically anomalous carbonate precipitation provides a framework for interpreting the reprise of these conditions on the Late Permian Earth. A paleoceanographic model that was developed to explain these stratigraphically linked phenomena suggests that the overturn of anoxic deep oceans during the Late Permian introduced high concentrations of carbon dioxide into surficial environments. The predicted physiological and climatic consequences for marine and terrestrial organisms are in good accord with the observed timing and selectivity of Late Permian mass extinction. 相似文献
50.
Spencer JR Stern SA Cheng AF Weaver HA Reuter DC Retherford K Lunsford A Moore JM Abramov O Lopes RM Perry JE Kamp L Showalter M Jessup KL Marchis F Schenk PM Dumas C 《Science (New York, N.Y.)》2007,318(5848):240-243
Jupiter's moon Io is known to host active volcanoes. In February and March 2007, the New Horizons spacecraft obtained a global snapshot of Io's volcanism. A 350-kilometer-high volcanic plume was seen to emanate from the Tvashtar volcano (62 degrees N, 122 degrees W), and its motion was observed. The plume's morphology and dynamics support nonballistic models of large Io plumes and also suggest that most visible plume particles condensed within the plume rather than being ejected from the source. In images taken in Jupiter eclipse, nonthermal visible-wavelength emission was seen from individual volcanoes near Io's sub-Jupiter and anti-Jupiter points. Near-infrared emission from the brightest volcanoes indicates minimum magma temperatures in the 1150- to 1335-kelvin range, consistent with basaltic composition. 相似文献