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81.
Nasal swab samples from clinically healthy California sea lions pups (Zalophus californianus) from six different reproductive rookeries in the Gulf of California were collected to determine the type and frequency of the representative aerobic bacterial microflora of their nasal mucosa. A total of 114 samples were examined and 100 bacterial isolates were identified and typified by microbiological and biochemical standard tests. Fifty four isolates corresponded to Gram positive bacteria (54%) and 46 isolates to Gram negative bacteria (46%). Fifteen bacterial genera were identified, including Micrococcus, Arcanobacterium, Corynebacterium, Moraxella, Neisseria, Escherichia, Kurthia, Acinetobacter, Staphylococcus, Brevibacillus, Bacillus, Klebsiella, Stenotrophomonas, Pseudomonas and Aeromonas. The most frequently isolated genera were Moraxella (24%), Micrococcus (18%), and Corynebacterium (15%). These results show the presence in the nasal cavity of sea lions of several microorganisms. Although considered part of the normal microflora, they may also be opportunistic pathogens for their hosts and may act as a potential natural sentinel of environmental changes.  相似文献   
82.
Placenta is formed by a parenchyma rich in extracellular matrix (ECM), and this structure guarantees the proper development of the embryo and placental functioning. Recently, studies have focused on the characterization of ECM in the placenta and foetal membranes of different species. This work aimed to analyse the composition of the ECM and to quantify the types of collagens in its composition. For this, 33 chorioallantoic membranes were used at different gestational ages, which were grouped into five groups. Subsequently, haematoxylin–eosin staining, Masson trichrome and picrosirius were performed for histological analysis. Through the technique of polarized light, it was possible to quantify the total collagen present in the membranes and finally the immunohistochemical technique was performed to verify the presence of collagens and glycoproteins. It was possible to verify that the chorioallantoic membranes have, in all the gestational periods of the initial third of gestation, the same histological structures, being the most significant difference the membrane thickening that occurs gradually during the gestation. However, we notice the appearance of binucleate cells only from group II. In addition, it was verified that a gradual increase of collagen occurs until the group IV, yet from the group V begins to occur a decrease of this protein. In addition, collagen I, collagen III, fibronectin and laminin were present in all membranes. With this, we concluded that the buffalo chorioallantoic membrane presents ECM in constant remodelling at the beginning of gestation and can be used as biomaterial in works on regenerative biology.  相似文献   
83.
The purpose of this work was to compare two different protocols of oestrous induction, using either a dopamine agonist (cabergoline) or a GnRH agonist (buserelin) in anoestrus bitches. The clinical trial involved 22 Beagle bitches, randomly allotted to two treatment groups: group A (n = 12) was orally administered cabergoline (Galastop®; Centralvet‐Vetem, Milan, Italy; 5 μg/kg SID), until the onset of cytological oestrus or for a maximum of 30 days and group B (n = 10) was treated with buserelin acetate, (Suprefact®; Aventis Pharma, Milan, Italy), administered subcutaneously t.i.d., at 1.5 μg/kg for 11 days and 0.75 μg/kg for the following 3 days. Blood samples were collected twice a week to measure progesterone and prolactin concentration. Both cabergoline and buserelin produced a significant early decline in prolactin concentration (p < 0.01), but the effect of cabergoline lasted longer. Progesterone concentration was significantly affected by buserelin administration, showing a significant increase (p < 0.01) from day 3 to day 6 of treatment. Cabergoline confirmed its effectiveness in inducing oestrus as 10 of 12 bitches responded to the treatment, were mated and whelped. On the contrary, oestrus was observed in only three of 10 buserelin‐treated bitches and in two of them 7 and 13 days after the end of treatment. These same two bitches accepted mating and conceived. The results suggest that in a clinical setting, dopaminergic treatment is the treatment of choice as it yields more consistent results and involves a much easier administration protocol.  相似文献   
84.
Tomatoes are consumed and cultivated all over the world for not only their pleasant taste but also their curative properties. Therefore, the challenge for growers is to obtain high-quality crop productions by developing new varieties of tomatoes or new ecofriendly fertilizers. This study was to test a bone glue-based foliar fertilizer on the tomato crop. The experiment was organized in a vegetation house under an original treatment scheme. Four types of foliar fertilizers were tested: macroelements, microelements and glue; macroelements and glue; microeleements and glue; and macroelements and microelements without glue. The fertilizers were applied as diluted solutions (0.5% and 1%) across three treatments applied on nine variants. The treatments with bone glue-based foliar fertilizer led to a high-quality production of healthy tomatoes, a good absorption of nutrients together with a reduced nitrites level in tomatoes and an increase of agricultural productivity. The applied foliar fertilizers tested on the hybrid tomatoes used in the experiment had a significant positive influence on vegetative growth. The nitrate concentration in the fruit did not exceed the maximum accepted level. The agronomic analysis of the mineral composition of the fruit revealed that foliar fertilizers with glue significantly influenced nutrient assimilation during the treatments. The level of nitrogen (N), phosphorus (P), and potassium (K) recovery following the application of bone glue foliar fertilizers was higher as compared to the control and the variant without bone glue. Biometric measurements had shown significant differences favorable to tomatoes treated with this bone glue foliar fertilizer.  相似文献   
85.
86.
Potato leaves infected with Phytophthora infestans produced a serine protease inhibitor (PLPKI) with specificity for microbial proteases. Sequencing of the first twenty residues at the NH2‐terminus of the mature PLPKI polypeptide demonstrated that PLPKI is a novel member of the potato protease inhibitor I family. PLPKI inhibited the activity of extracellular proteases produced by two pathogens of potato, P. infestans and Rhizoctonia solani, but was inactive against proteases secreted into the culture media by the binucleate Rhizoctonia N2, a non‐pathogenic fungus for potato. Western blot analysis showed a positive correlation between the levels of PLPKI and the degree of horizontal resistance, showing its highest accumulation in clone OKA 5632.11, which has been described as highly resistant. This correlation, together with the ability of PLPKI to completely abolish the secreted serine protease activity of P. infestans, suggests that PLPKI may have an active role in protecting potato plants from this pathogenic oomycete and that it could be used as a suitable biochemical marker to help breeders in the selection of cultivars with high degree of horizontal resistance.  相似文献   
87.
A cryopreservation process usingencapsulation/dehydration technique was setup for apical meristem-tips of invitro plantlets of `paradise tree' (Melia azedarach L. var. gigantea,clone `El dorado'). Apical meristem-tipswere cultured for one day on MS basalmedium with 2 M BA and 0.5 M IBAand encapsulated with 3% sodium alginate.The highest shoot proliferation rate aftercryopreservation was obtained whenencapsulated apical meristem-tips werepregrown for 3 days in liquid medium with0.5, 0.75 and 1 M of sucrose for 24 hoursprogressively, desiccated for 5 hours withsilicagel followed by rapid or slowcooling. Survival after freezing in liquidnitrogen ranged between 67–83% andshoot proliferation ranged between 43–60%. This cryopreservation treatmentpreserved genetic stability, when it wasevaluated using the electrophoreticpatterns of nine isozyme systems and RAPDprofiles.  相似文献   
88.
In some areas of the tropics forests are recovering on abandoned cattle pastures. These secondary forests may be important habitats for conserving biodiversity, but we know little about their species composition over the long term. We studied herpetofaunal community changes in a 40 years chronosequence of forest succession on abandoned pastures in Puerto Rico. Twelve submontane sites (100-250 masl) represented four forest recovery stages: pasture, young (1-5 years after abandonment), intermediate (10-20 years), and advanced (40 years). Among these stages we analyzed the relationship of forest structure, microclimate, and herpetofaunal community structure. During succession total forest height increased, new strata of vegetation appeared in the understory, and the forest gained heterogeneity and complexity. Microclimate changed with changes in the physiognomy and structure of the vegetation. Microclimatic shifts were more dramatic in forest <20 years since abandonment. During 1 year we observed 7991 individuals of thirteen reptilian species (60% of observations) and six anuran species. Herpetofaunal richness was similar among stages, but the total abundance increased through succession. Relative abundance of anurans and reptiles was similar between stages, but species dominance changed with succession. Forest >20 years old resembles mature forest in some structural characteristics important to herpetofauna and can provide habitat for forest herpetofauna in disturbed areas.  相似文献   
89.
Evaluation of the parameters affecting the compostability of dewatered raw sludge from a wastewater treatment plant has been carried out by means of a full factorial composite experimental design. The factors and their correspondent levels considered in the experimental design were: bulking agent:sludge ratio (from 1:1 to 4:1 by volume), bulking agent particle size (from 0-5 mm to 10-20 mm) and composting volume (in the range of typical laboratory-scale, from 1.5 to 25 L). Experimental design has permitted obtaining a polynomial second-order function that quantitatively describes the influence of the considered factors on the compostability of this waste in laboratory reactors. The function has been numerically optimized to find the optimal values for composting raw sludge resulting in a values of: 0-5 mm for bulking agent size, 1:1 for ratio bulking agent:sludge and a composting volume around 10 L. The use of this technique can be generalized and applied to the composting of other organic wastes and will permit comparison of composting performance of different wastes.  相似文献   
90.
Butyrate is a byproduct of microbial carbohydrate fermentation that occurs primarily in the large intestine. When added to feed, butyrate quickly disappears in the upper digestive tract. Because butyrate is important for epithelial cell development, mucosal integrity, and animal growth, an encapsulation technique has been developed that allows for the slow release of butyrate into the small and large intestines. The purpose of this study was to describe the in vitro release of calcium [1-(14)C]butyrate, formulated into a slow-release (protected) bead, into water and simulated intestinal fluids and to compare the in vivo absorption and disposition of unprotected versus protected calcium [1-(14)C]butyrate in broiler chicks. Formulation of calcium [1-(14)C]butyrate into protected beads allowed release of 5.8 ± 0.2 and 3.4 ± 0.2% of the formulated radiocarbon into water and gastric fluid, respectively, after 2 h of incubation. Beads incubated in gastric fluid for 2 h and subsequently incubated in simulated intestinal fluid released a total of 17.4 ± 0.8% of the formulated radioactivity. Release of respiratory [(14)C]CO(2) after oral dosing of aqueous calcium [1-(14)C]butyrate in broiler chicks peaked at 15.2 ± 5.2% per hour 1.5 h after dosing; in contrast, maximal rates of release in chicks dosed with protected calcium [1-(14)C]butyrate occurred 4 h after dosing at 9.0 ± 3.1% per hour. The data suggested an improved efficacy of protected butyrate delivery to intestinal tissues over nonprotected butyrate. This study confirmed that encapsulation strategies designed to enhance delivery of ingredients to improve intestinal health are effective at prolonging intestinal exposure to butyrate. Encapsulation of such ingredients might benefit the food and feed industries.  相似文献   
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