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171.
Summary

The disposition and urinary excretion of ciprofloxacin (CIP) following intravenous (IV) or intramuscular (IM) administration of 7.5 mg/kg body weight in sheep (n = 5) was studied. The intravenous plasma concentration curve was best described pharmacokinetically by a two‐compartment open model, while the intramuscular administration data fitted better to a one‐compartment open model. Mean elimination half‐lives after IV and IM administration were 72 and 184 minutes, respectively. The absorption of intramuscularly administered CIP in sheep was fast: maximal plasma concentration (Cmax) was reached quickly (tmax 31.93 min) and attained values of 0.69 ± 0.27 mg/l. The bioavailability was 49%. The urinary data showed a significant decrease in the elimination rate constant of CIP when CIP was administered intramuscularly. The other parameters calculated did not display differences between the two routes of administration. The results obtained suggest that when CIP was administered by the IM route in the assayed dose, it was able to maintain serum concentrations above the MIC of most common pathogens over an 8‐hour period.  相似文献   
172.
173.
The morphology of the ovaries and oogenesis of Pimelodella vittata were studied using anatomical and histological techniques to provide information of its reproductive biology. Eighty adult females were captured trimonthly during the period November 2005 to October 2006. The ovaries are paired, saculiform organs, which are coated with tunica albuginea and contain ovigerous lamellae, where the oocytes develop before being released into the ovarian lumen and following the ovarian duct until reaching the genital papilla. Oogenesis was divided into stages based on the alterations to the nucleus, ooplasm and surrounding follicular layers. Oogonia form groups from the germinal epithelium have asynchronous development and differentiate into initial perinucleolar oocytes. The formation of the zona pellucida is initiated in the advanced perinucleolar oocytes reaching a thickness of 1.46 ± 0.58 μm in the vitellogenic oocytes. The follicular cells are squamous in perinucleolar oocytes, become cubical in the pre‐vitellogenic oocytes and prismatic in the vitellogenic oocytes with a height of 11.20 ± 4.74 μm. The histochemical reactions indicate that zona pellucida, cortical alveoli and yolk globules contain neutral glycoproteins and the follicular cells contain neutral glycoproteins in association with carboxylated and sulphated glycoconjugates. Statistical analyses showed significant differences in the diameter of the oocytes and follicular cells height as oocytes matured. This study represents the first data about the ovarian structure and oogenesis of this species.  相似文献   
174.
The aim of this research was to characterize the preantral ovarian follicular population in collared peccaries (Tayassu tajacu) using light and electron microscopy. Ovaries from six mature females were collected and further fixed for histological and ultrastructural analysis. A total of 33273.45 ± 5789.99 preantral follicles (PFs) were estimated for the population in each ovary. Most preantral follicles were primordial (91.56%), followed by primary (6.29%) and secondary (2.15%) ones. Most PFs were morphologically normal (94.4%), and only a few were atretic (5.6%). At histology assessment, amounts of lipid droplets were observed into the oocyte cytoplasm, which was confirmed through ultrastructural analysis. This work characterizes for the first time the ovarian population of preantral follicles, total and per category, in collared peccaries (Tayassu tajacu). The general follicles featured at primordial, primary and secondary categories are very similar to those described for other species.  相似文献   
175.
The aim of this study was to measure the levels of inflammatory mediators in serum from horses naturally infected with Trypanosoma vivax. Banked serum samples collected during a previously reported T. vivax natural infection were used to analyze proinflammatory cytokines such as interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), interleukin 1 (IL-1), interleukin 6 (IL-6), and nitrite/nitrate (NOx) levels. We evaluated 12 serum samples from horses from a farm in southern Brazil, four of which had parasitological and molecular diagnoses for T. vivax and presented with clinical signs of disease. Cytokines were assessed by quantitative sandwich enzyme-linked immunosorbent assay, and NOx was measured using the modified Griess method. Levels of IFN-γ, TNF-α, IL-1, IL-6, and NOx were increased in serum of infected animals compared to that in noninfected animals. Therefore, infection with T. vivax caused an increase in proinflammatory cytokines and nitric oxide content.  相似文献   
176.
The aim of this systematic review was to identify, assess, and critically evaluate the quality of evidence of nonsteroidal anti‐inflammatory drug (NSAID)‐induced adverse effects in dogs. Original prospective studies published in peer‐reviewed journals in English (1990–2012) that reported data on the safety of NSAIDs administration in dogs were searched. For each study, design type (I, II, III, or IV) and assessment of quality (+, Ø, ?) were rated. For each drug, quantity and consistency rating (***, **, *) and strength of evidence (high, moderate, low, or extremely low) were identified and evaluated. The strength of evidence was defined in terms of how applicable and relevant the conclusions were to the target population. Sixty‐four studies met the inclusion criteria. Thirty‐five (55%) research studies and 29 (45%) clinical trials were identified. A high strength of evidence existed for carprofen, firocoxib, and meloxicam; moderate for deracoxib, ketoprofen, and robenacoxib; and low for etodolac. Quality and consistency rating were as follows: carprofen (***/***), deracoxib (**/***), etodolac (*/unable to rate), firocoxib (***/**), ketoprofen (**/***), meloxicam (***/***), and robenacoxib (**/**), respectively. Adverse effects were detected in 35 studies (55%) and commonly included vomiting, diarrhea, and anorexia. Three studies (5%) reported a power analysis related to adverse effects of ≥80%. In randomized, placebo‐controlled, blinded studies (n = 25, 39%), the incidence of adverse effects was not statistically different between treated and control dogs. Finally, most studies were not appropriately designed to determine the safety of NSAIDs, and involved a healthy nongeriatric population of research dogs.  相似文献   
177.
Due to decades of loss of grassland diversity across Europe, there is a need to identify factors affecting species composition and diversity in managed meadows. The aim of the current study was to assess how ecological, landscape and management factors may affect plant species composition, biodiversity and forage value in Alpine hay meadows. Species composition, Shannon index and forage value were obtained from phytosociological relevés. Twenty explanatory variables were selected from a set of ecological, landscape and management factors. Their effects on plant species composition, Shannon index and forage value were analysed by applying the variation partitioning approach. Plant species composition was related to sixteen factors, explaining 35·6% of the variability. Shannon index and forage value were related to eleven factors, explaining 47·8 and 40·8% of their total variation respectively. Ecological factors were the main set explaining species composition and diversity, whereas none of the three individual groups of factors (ecological, landscape, management) significantly explained variability within forage value. Overall, the effects of the three groups of factors accounted for 70% of the total variability in plant species composition, but less than half that of Shannon index and of forage value.  相似文献   
178.
A vital ingredient for engineering bone tissue, in the culture dish, is the use of recombinant matrix and growth proteins to help accelerate the growth of cultivated tissues into clinically acceptable quantities. The skeletal organic matrices of calcifying marine invertebrates are an untouched potential source of such growth inducing proteins. They have the advantage of being ready-made and retain the native state of the original protein. Striking evidence shows that skeleton building bone morphogenic protein-2/4 (BMP) and transforming growth factor beta (TGF-β) exist within various marine invertebrates such as, corals. Best practice mariculture and the latest innovations in long-term marine invertebrate cell cultivation can be implemented to ensure that these proteins are produced sustainably and supplied continuously. This also guarantees that coral reef habitats are not damaged during the collection of specimens. Potential proteins for bone repair, either extracted from the skeleton or derived from cultivated tissues, can be identified, evaluated and retrieved using chromatography, cell assays and proteomic methods. Due to the current evidence for bone matrix protein analogues in marine invertebrates, together with the methods established for their production and retrieval there is a genuine prospect that they can be used to regenerate living bone for potential clinical use.  相似文献   
179.
In this work, we investigated the spasmolytic effect of caulerpine, a bisindole alkaloid isolated from marine algae of the Caulerpa genus, on guinea pig ileum. Our findings indicated that caulerpine inhibited phasic contractions induced by carbachol (IC50 = 7.0 ± 1.9 × 10−5 M), histamine (IC50 = 1.3 ± 0.3 × 10−4 M) and serotonin (IC50 = 8.0 ± 1.4 × 10−5 M) in a non-selective manner. Furthermore, caulerpine concentration-dependently inhibited serotonin-induced cumulative contractions (pD′2 = 4.48 ± 0.08), shifting the curves to the right with Emax reduction and slope of 2.44 ± 0.21, suggesting a noncompetitive antagonism pseudo-irreversible. The alkaloid also relaxed the ileum pre-contracted by KCl (EC50 = 9.0 ± 0.9 × 10−5 M) and carbachol (EC50 = 4.6 ± 0.7 × 10−5 M) in a concentration-dependent manner. This effect was probably due to inhibition of Ca2+ influx through voltage-gated calcium channels (CaV), since caulerpine slightly inhibited the CaCl2-induced contractions in depolarizing medium without Ca2+, shifting the curves to the right and with Emax reduction. According to these results, the spasmolytic effect of caulerpine on guinea pig ileum seems to involve inhibition of Ca2+ influx through CaV. However, other mechanisms are not discarded.  相似文献   
180.
This report describes the use of a pressure-sensitive walkway to evaluate an uncommon case of a cat with dorsal luxation of the left scapula and an amputated right forelimb. The findings suggest that limb amputation induced load redistribution mostly to the contralateral forelimb despite the scapular luxation.  相似文献   
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