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51.
DK Keefer SD deFrance ME Moseley JB Richardson DR Satterlee A Day-Lewis 《Science (New York, N.Y.)》1998,281(5384):1833-1835
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
52.
Predatory dinosaur remains from madagascar: implications for the cretaceous biogeography of gondwana 总被引:1,自引:0,他引:1
SD Sampson LM Witmer CA Forster DW Krause PM O'Connor P Dodson F Ravoavy 《Science (New York, N.Y.)》1998,280(5366):1048-1051
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
53.
Apparent digestibility of nitrogen and amino acids in protein feedstuffs by growing pigs 总被引:3,自引:0,他引:3
D A Knabe D C LaRue E J Gregg G M Martinez T D Tanksley 《Journal of animal science》1989,67(2):441-458
Eight digestion trials were conducted with pigs fitted with ileal T-cannulas to determine the apparent digestibilities of N and amino acids in common protein feedstuffs. Trial-to-trial variation was minimal as determined by the variation in digestibilities for soybean meal, which was evaluated in each trial. Apparent digestibilities varied widely; ileal N digestibility ranged from 88 to 63%, and ileal lysine digestibility ranged from 93 to 40%. In general, ring-dried blood meal, corn gluten meal, Menhaden fish meal, poultry-by-product meal and extruded whole soybeans were the most digestible, followed by canola meal, sunflower meal, peanut meal and meat and bone meal. Cottonseed meal and feather meal were the least digestible. Mean values for each feedstuff agree well with published data. Variation in digestibilities among samples of the same feedstuff was greater for the meat and bone meals. Regression of ileal essential amino acid digestibilities on ileal and fecal N digestibility indicated that amino acid digestibilities can be predicted more precisely from ileal N digestibility than from fecal N digestibility. However, neither ileal nor fecal N digestibility could be used with a high degree of certainty to predict ileal amino acid digestibilities. 相似文献
54.
Apparent digestibility of amino acids, gross energy and starch in corn, sorghum, wheat, barley, oat groats and wheat middlings for growing pigs 总被引:1,自引:0,他引:1
Apparent nutrient digestibilities of yellow-dent corn, low-tannin sorghum, hard red winter wheat, barley, oat groats and wheat middlings were determined near the end of the small intestine and over the total digestive tract of growing pigs. Gross energy digestibilities for corn, sorghum and oat groats were similar; wheat had a slightly lower (P less than .05) digestibility, followed by barley (P less than .05), with wheat middlings being the least (P less than .05) digestible. About 7% of the gross energy in corn, sorghum, wheat and oat groats was digested in the large intestine, compared with 11% for barley and 17% for wheat middlings. The starch in all products was essentially 100% digestible by the end of the small intestine. Ileal amino acid digestibilities tended to be highest for wheat and oat groats, followed by corn, sorghum, barley and wheat middlings. The range in ileal digestibilities was 73.8 (sorghum) to 84.2% (wheat) for lysine, 69.6 (corn) to 81.4% (wheat) for tryptophan and 63.4 (wheat middlings) to 77.9% (oat groats) for threonine. Amino acid digestibilities determined over the total tract were generally higher than ileal digestibilities; however, values for lysine, methionine and phenylalanine were generally lower, indicating a net synthesis of these amino acids in the large intestine. 相似文献
55.
A 13-year-old Morgan gelding was examined for right forelimb lameness and tenosynovitis of the right common carpal sheath of the digital flexor tendons. The horse had moderate right forelimb lameness at the trot and marked effusion of the right common carpal sheath of the digital flexor tendons. Ultrasonographic examination revealed a soft tissue mass within the proximal pouch of the affected tendon sheath, located adjacent to the distal physis of the radius. Cytology and culture of the fluid revealed a sterile, eosinophilic tenosynovitis. Tenoscopic exploration confirmed the presence of a capsulated soft tissue mass. Thecotomy was required to fully debride the mass, which histology revealed to be a mast cell tumour. At 22 months postoperatively, the horse developed mild right forelimb lameness and eosinophilic tenosynovitis because of recurrence of the mastocytoma. Mastocytosis is a possible differential diagnosis in any horse exhibiting lameness associated with tenosynovitis. Surgical excision combined with rest and postoperative intrasynovial and systemic corticosteroids may be palliative. 相似文献
56.
Charles W. Frevert DVM Angeline E. Warner DVM SD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1992,6(3):154-165
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
57.
58.
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
59.
M‐J Sánchez‐Calabuig C López‐Fernández E Martínez‐Nevado JF Pérez‐Gutiérrez J de la Fuente SD Johnston D Blyde K Harrison J Gosálvez 《Reproduction in domestic animals》2014,49(5):761-768
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 (r = 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 (r = 0.993; p = 0.01) between the data obtained in the laboratory and in the field. 相似文献
60.
Biological investigations have the potential to produce large volumes of data, much of which is condensed or omitted from publications, and which may not be readily accessible to researchers outside that discipline. Bringing together in a single repository information whose common thread is the Solanaceae family gives researchers a valuable, multidisciplinary tool. The SolGenes (Solanaceae) database project, a part of the USDA Plant Genome Research Program, is meant to be such a tool. The database has facilities for handling genetic and physical maps, DNA sequences, pathologies and germplasm stocks, as well as other types of information. It currently contains tomato, potato and pepper genetic maps based on a common set of probes, tomato germplasm data including wild species and stocks, autoradiogram images of distributed probes and much more. Current efforts are focused on loading images of tomato mutants, expanding the germplasm data, and setting up a gopher server. The database software (ACEDB) provides a user-friendly, graphical interface with links between logically related pieces of information, allowing the user to view data from multiple sources with just a few clicks of the mouse. The database and software are freely available to interested parties.Abbreviations ftp
file transfer protocol 相似文献