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41.
Because of improved management of animals in intensive care facilities, veterinarians are often confronted with patients at risk of developing adult respiratory distress syndrome (ARDS). The four objectives of this review are: 1) to describe the clinical conditions which place animals at risk for development of ARDS, 2) to give the reader a comprehensive understanding of the pathophysiology of endotoxin-induced lung injury, 3) to address the interspecies variability in susceptibility to endotoxin-induced lung injury, and 4) to outline areas where veterinarians should be concentrating their diagnostic and therapeutic efforts with regards to this syndrome. Because there is little written in the veterinary literature on ARDS, this review will rely heavily on the human ARDS literature as well as on research in animal models of acute lung injury.  相似文献   
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Artificial insemination (AI) and semen cryopreservation has significantly improved the breeding potential of male animals. However, current freezing techniques commonly result in reduced semen quality. Ten years ago, a unique freezing technology (UFT) was developed for the freezing of foodstuffs and other materials. Previous work from this laboratory has demonstrated the UFT to be a superior method of freezing for a number of cell types. In a preliminary study, the UFT was compared with the conventional freezing methodology of bovine semen. Semen samples were collected from an angus (Bull A) and a gelbivich bull (Bull B), prepared using a conventional bovine cryoprotectant, and frozen in the UFT or in liquid nitrogen (LN) mist. The samples were stored in LN before being thawed and assessed for the semen parameters of motility and forward progression. Preliminary results suggest the UFT is equivalent to current techniques in the cryopreservation and recovery of bovine semen, and with modification, possibly a superior technique for semen freezing. Further studies using larger sample populations, and using a CASA system to evaluate motility, forward progression and linearity are merited.  相似文献   
44.
Over the last two decades, there have been significant advances in the use of assisted reproductive technology for genetic and reproductive management of captive dolphin populations, including evaluation of sperm DNA quality. This study validated a customized sperm chromatin dispersion test (SCDt) for the bottlenose dolphin (Tursiops truncatus) as a means of assessing sperm DNA damage both in the field and in the laboratory. After performing the SCDt, two different sperm morphotypes were identified: (i) sperm with fragmented DNA showed large haloes of dispersed DNA fragments emerging from a compact sperm nucleoid core and (ii) sperm containing non‐fragmented DNA displayed small compact haloes surrounded by a dense core of non‐dispersed DNA and protein complex. Estimates of sperm DNA fragmentation by means of SCDt were directly comparable to results obtained following a two‐tailed comet assay and showed a significant degree of correlation (= 0.961; p < 0.001). This investigation also revealed that the SCDt, with minor modifications to the standard protocol, can be successfully conducted in the field using a LED florescence microscopy obtaining a high correlation (= 0.993; p = 0.01) between the data obtained in the laboratory and in the field.  相似文献   
45.
Analyses of fossil mammal faunas from 2945 localities in the United States demonstrate that the geographic ranges of individual species shifted at different times, in different directions, and at different rates in response to late Quaternary environmental fluctuations. The geographic pattern of faunal provinces was similar for the late Pleistocene and late Holocene, but differing environmental gradients resulted in dissimilar species composition for these biogeographic regions. Modern community patterns emerged only in the last few thousand years, and many late Pleistocene communities do not have modern analogs. Faunal heterogeneity was greater in the late Pleistocene.  相似文献   
46.
Juçara (Euterpe edulis M.) fruits are an interesting source of phenolic compounds, mainly anthocyanins, making them valuable to the food and pharmaceutical industries. Juçara fruits were harvested along the on-tree ripening process between March and June as practiced in Paraná state, Brazil and examined for their total anthocyanin content (TAC), total phenolic content (TPC), total phenolic acid (TPA) and total antioxidant capacity (TAA). Overall, TAC increased (91.52–236.19 mg cyanidin-3-glucoside equivalent/100 g dm) whereas TPC (81.69–49.09 mg GAE/g dm) and TPA (44.27–30.95 mg/100 g dm) decreased during ripening of juçara fruits. Use of tandem mass spectrometry allowed the identification of cyanidin-3,5-diglucoside, peonidin-3-glucoside and peonidin-3-rutinoside for the first time in juçara fruits. The analysis of the phenolic acids by HPLC-MS/MS indicated the presence of gallic, protocatechuic, p-hydroxybenzoic, vanillic, chlorogenic, caffeic, syringic, p-coumaric, sinapinic and ferulic acids. The high antioxidant capacity using DPPH radical scavenging capacity (655.89–745.32 μmol TE/g dm) and ORAC assays (1088.10–2071.55 μmol TE/g dm) showed that juçara fruits have potential as a source of novel natural antioxidants for disease prevention and health promotion, and also as natural food additives for developing new functional food products.  相似文献   
47.
The archaeological site of Quebrada Tacahuay, Peru, dates to 12,700 to 12,500 calibrated years before the present (10,770 to 10,530 carbon-14 years before the present). It contains some of the oldest evidence of maritime-based economic activity in the New World. Recovered materials include a hearth, lithic cutting tools and flakes, and abundant processed marine fauna, primarily seabirds and fish. Sediments below and above the occupation layer were probably generated by El Nino events, indicating that El Nino was active during the Pleistocene as well as during the early and middle Holocene.  相似文献   
48.
Recent discoveries of fossil vertebrates from the Late Cretaceous of Madagascar include several specimens of a large theropod dinosaur. One specimen includes a nearly complete and exquisitely preserved skull with thickened pneumatic nasals, a median frontal horn, and a dorsal projection on the parietals. The new materials are assigned to the enigmatic theropod group Abelisauridae on the basis of a number of unique features. Fossil remains attributable to abelisaurids are restricted to three Gondwanan landmasses: South America, Madagascar, and the Indian subcontinent. This distribution is consistent with a revised paleogeographic reconstruction that posits prolonged links between these landmasses (via Antarctica), perhaps until late in the Late Cretaceous.  相似文献   
49.
This research assessed four levels of crude protein—200, 250, 300 and 350 g/kg—associated with two crude lipid concentrations—110 and 140 g/kg—in diets for juveniles of tambatinga (♀Colossoma macropomum × ♂Piaractus brachypomus) over 63 days. The fish (15.2 ± 0.2 g) were distributed in 24–160 L tanks (11 fish/tank) in a 4 × 2 completely randomized factorial design (n = 3). Increasing the lipid content in the diets reduced (p < 0.05) the protein requirements for weight gain from 326 g/kg (diets with 110 g/kg LIP) to 255 g/kg (diets with 140 g/kg). Protein retention in the fish increased (p < 0.05) when they were fed up to 293 g/kg CP and 140 g/kg LIP; in the diets with 110 g/kg LIP, protein retention decreased linearly (p < 0.05) as the protein content in the diets increased. Feed efficiency increased (p < 0.05) when the fish received up to 308 g/kg CP regardless of lipid concentration (p > 0.05). In conclusion, tambatinga juveniles at 15–120 g have a minimum requirement of 255 g/kg CP and 140 g/kg CL and a protein:energy ratio of 17.4 g CP kJ/digestible energy (DE).  相似文献   
50.
Information on nutritional requirement of some Brazilian farmed fish species, especially essential amino acids (EAA) requirements, is scarce. The estimation of amino acids requirements based on amino acid composition of fish is a fast and reliable alternative. Matrinxa, Brycon amazonicus, and curimbata, Prochilodus lineatus, are two important Brazilian fish with potential for aquaculture. The objective of the present study was to estimate amino acid requirements of these species and analyze similarities among amino acid composition of different fish species by cluster analysis. To estimate amino acid requirement, the following formula was used: amino acid requirement = [(amount of an individual amino acid in fish muscle tissue) × (average totalEAA requirement among channel catfish, Ictalurus punctatus, Nile tilapia, Oreochromis niloticus, and common carp, Cyprinus carpio)]/(average fish muscle totalEAA). Most values found lie within the range of requirements determined for other omnivorous fish species, in exception of leucine requirement estimated for both species, and arginine requirement estimated for matrinxa alone. Rather than writing off the need for regular dose–response assays under the ideal protein concept to determine EAA requirements of curimbata and matrinxa, results set solid base for the study of tropical species dietary amino acids requirements.  相似文献   
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