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1.
Mussels close their shell as a protective strategy and the quantification of this behavioral marker may represent an alarm signal when they are exposed to environmental stressors. In the present study, we investigated the ability of the Mediterranean mussel Mytilus galloprovincialis to recover and then the resilience or inertia of valve activity after a pulsing exposition to diverse levels of salinity (5, 10, 20, and 35 PSU as reference value). The trial simulated an event of drastic and sudden reduction of seawater salinity thus mimicking an event of flash flood from intense rain. Valve gaping and movements were measured in continuous cycle for 10 days using a customized magneto-electric device which uses Hall sensors. Results showed that under normal conditions of salinity (35 PSU), the general pattern of valve movements was a continuously open state with sporadic spikes indicating a closing motion. At salinity of 5, PSU mussels reacted by closing their valves, leading to a 77% mortality on the 4th day. At salinity of 10, PSU animals were observed with closed valves for the entire duration of the exposure and no mortality occurred, they showed a significant reduction in the valve activity once the reference value of salinity was re-established. In contrast, salinity of 20 PSU did not trigger a significant behavioral response. Interestingly, there no define rhythms of valve movements were recorded during salinity challenges.  相似文献   
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OBJECTIVE: To compare cardiovascular and systemic effects and analgesia during the postoperative period of epidural anesthesia performed with bupivacaine alone or with fentanyl or sufentanil in bitches maintained at a light plane of anesthesia with continuous infusion of propofol. STUDY DESIGN: Prospective randomized masked clinical trial. ANIMALS: 30 female dogs of various breeds. PROCEDURES: Dogs were allocated into 3 groups of 10 each. One group received fentanyl (2 microg/kg [0.91 microg/lb]) and bupivacaine (1 mg/kg [0.45 mg/lb]), 1 group received sufentanil (1 microg/kg) and bupivacaine (1 mg/kg), and 1 group received bupivacaine (1 mg/kg). All dogs received acepromazine (0.1 mg/kg [0.045 mg/lb]) and continuous infusion of propofol for sedation. The agents were administered into the lumbosacral space and diluted in saline (0.9% NaCl) solution to a total volume of 0.36 mL/kg (0.164 mL/lb). Cardiac and respiratory rates, arterial blood pressures, pH, and blood gases were evaluated. Analgesia, sedation level, serum cortisol concentrations, and plasma catecholamine concentrations were measured regularly for 6 hours. RESULTS: No important changes in cardiovascular, respiratory, or sedation variables were observed. Degree of analgesia in the postoperative period was higher in the sufentanil group, although use of fentanyl and bupivacaine also resulted in a sufficient level of analgesia. CONCLUSIONS AND CLINICAL RELEVANCE: Use of the 3 anesthetic techniques permitted ovariohysterectomy with sufficient analgesia and acceptable neuroendocrine modulation of pain with minimal adverse effects.  相似文献   
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Negative refraction in metamaterials has generated great excitement in the scientific community. Although negative refraction has been realized in microwave and infrared by using metamaterials and by using two-dimensional waveguide structures, creation of a bulk metamaterial showing negative refraction at visible frequency has not been successful, mainly because of the significant resonance losses and fabrication difficulties. We report bulk metamaterials made of nanowires that show such negative refraction for all incident angles in the visible region. Moreover, the negative refraction occurs far from any resonance, resulting in a low-loss and a broad-band propagation at visible frequencies. These remarkable properties can substantially affect applications such as imaging, three-dimensional light manipulation, and optical communication.  相似文献   
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Flow cytometry is an essential tool for dissecting the functional complexity of hematopoiesis. We used single-cell "mass cytometry" to examine healthy human bone marrow, measuring 34 parameters simultaneously in single cells (binding of 31 antibodies, viability, DNA content, and relative cell size). The signaling behavior of cell subsets spanning a defined hematopoietic hierarchy was monitored with 18 simultaneous markers of functional signaling states perturbed by a set of ex vivo stimuli and inhibitors. The data set allowed for an algorithmically driven assembly of related cell types defined by surface antigen expression, providing a superimposable map of cell signaling responses in combination with drug inhibition. Visualized in this manner, the analysis revealed previously unappreciated instances of both precise signaling responses that were bounded within conventionally defined cell subsets and more continuous phosphorylation responses that crossed cell population boundaries in unexpected manners yet tracked closely with cellular phenotype. Collectively, such single-cell analyses provide system-wide views of immune signaling in healthy human hematopoiesis, against which drug action and disease can be compared for mechanistic studies and pharmacologic intervention.  相似文献   
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Target region amplification polymorphism (TRAP) is a relatively new PCR-based technique that detects large numbers of loci in a single reaction without extensive pre-PCR processing of samples. The aim of this study was to integrate TRAP markers in an EST-derived SSR linkage map of a RIL mapping population from the cross of the durum wheat cultivars Ciccio and Svevo, for a more general purpose of establishing a high-throughput system for genetic map saturation. Primer combinations producing PCR products with at least 4–5 polymorphic bands were selected and analyzed across the mapping population. The PCR reactions produced a total of 2,881 fragments with an average of 52 peaks per reaction. A total of 142 new TRAP markers were mapped and found to be randomly distributed in the genome. The total length of the map was 2,043.0 cM, with an average chromosome length of 145.9 cM. Homoeologous group one had the highest number of TRAP markers (38 loci) and the longest map length (407.9 cM) for a total of 87 markers, while the homoeologous group five had the lowest TRAP marker number (5 loci) and the shortest map length (232.5 cM). The distribution of markers among the seven homoeologous groups was random. The results indicate that TRAP is highly efficient in genetic mapping, generating a large number of markers scattered across the genome. This closes many existing gaps in marker coverage and may join otherwise separate linkage groups.  相似文献   
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Journal of Crop Science and Biotechnology - Superoxide dismutases (SODs) are a group of enzymes that play essential roles in catalyzing the dismutation of superoxide radicals to protect cells from...  相似文献   
9.
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   
10.
Approaches for the capillary gas chromatographic (GC) based analysis of intact plant stanyl esters in enriched foods were developed. Reference compounds were synthesized by enzyme-catalyzed transesterifications. Their identities were confirmed by means of mass spectrometry. Using a medium polar trifluoropropylmethyl polysiloxane stationary phase, long-chain plant stanyl esters could be separated according to their stanol moieties and their fatty acid chains. Thermal degradation during GC analysis was compensated by determining response factors; calibrations were performed for ten individual plant stanyl esters. For the analysis of low-fat products (skimmed milk drinking yogurts), the GC separation was combined with a "fast extraction" under acidic conditions. For fat-based foods (margarines), online coupled LC-GC offered an elegant and efficient way to avoid time-consuming sample preparation steps. The robust and rapid methods allow conclusions on both, the stanol profiles and the fatty acid moieties, and thus provide a basis for the authentication of this type of functional food ingredients.  相似文献   
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