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排序方式: 共有630条查询结果,搜索用时 15 毫秒
621.
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Ultrabasic (pH > 11) water issues from some fresh ultramafic bodies. The properties of the ultrabasic solutions are believed to be due to current reactions yielding serpentine from primary olivines and pyroxenes. The low concentrations of divalent airon. divalent magnesium, and dissolved silica from the serpentinization require an increase in rock volume. 相似文献
624.
Barnes JW Brown RH Turtle EP McEwen AS Lorenz RD Janssen M Schaller EL Brown ME Buratti BJ Sotin C Griffith C Clark R Perry J Fussner S Barbara J West R Elachi C Bouchez AH Roe HG Baines KH Bellucci G Bibring JP Capaccioni F Cerroni P Combes M Coradini A Cruikshank DP Drossart P Formisano V Jaumann R Langevin Y Matson DL McCord TB Nicholson PD Sicardy B 《Science (New York, N.Y.)》2005,310(5745):92-95
Observations from the Cassini Visual and Infrared Mapping Spectrometer show an anomalously bright spot on Titan located at 80 degrees W and 20 degrees S. This area is bright in reflected light at all observed wavelengths, but is most noticeable at 5 microns. The spot is associated with a surface albedo feature identified in images taken by the Cassini Imaging Science Subsystem. We discuss various hypotheses about the source of the spot, reaching the conclusion that the spot is probably due to variation in surface composition, perhaps associated with recent geophysical phenomena. 相似文献
625.
626.
627.
Toxicity in three dogs from accidental oral administration of a topical endectocide containing moxidectin and imidacloprid 总被引:1,自引:1,他引:0
Three dogs were presented with a history of oral administration of a topical endectocide containing imidacloprid and moxidectin. They were diagnosed with imidacloprid and moxidectin intoxication, having ingested doses ranging from 7.5 to 1.4 mg/kg of imidacloprid and 1.9 to 2.8 mg/kg of moxidectin. The three dogs were affected to different degrees of severity, but all displayed signs of ataxia, generalised muscle tremors, paresis, hypersalivation and disorientation. Temporary blindness occurred in two cases. The three dogs were tested for the presence of the multi-drug resistance 1 gene deletion, which can cause an increased sensitivity to the toxic effects of moxidectin, and were found to be negative. Treatment included gastrointestinal decontamination, intravenous fluid therapy and benzodiazepines to control muscle tremors. All three dogs made a complete recovery within 48 h of ingestion. 相似文献
628.
Incidence of lymphoma in a captive-bred colony of hamadryas baboons (Papio hamadryas) 总被引:1,自引:1,他引:0
LE Graves A Hennessy NS Sunderland SJ Heffernan SE Thomson 《Australian veterinary journal》2009,87(6):238-243
Objective To assess the incidence of lymphoma and wasting-related deaths in the National Baboon Colony of Australia and relate it to the presence of simian T-cell lymphotrophic virus 1 (STLV-1) infection.
Design and procedure The records of all animals that had died since establishment of the National Baboon Colony in Australia were reviewed retrospectively. The clinical signs and histopathological findings were recorded and assessed to determine the involvement of lymphoma in the deaths. The presence of STLV-1 was recorded if known and correlated with the STLV-1 status of the colony.
Results Of the deaths from disease or illness, 53% were diagnosed as or suspected to be lymphoma, occurring in mature animals with no sex predisposition. The most common presentation was rapidly occurring generalised lymphadenomegaly.
Conclusions This study has described a relatively high prevalence of lymphoma in a colony of captive-bred baboons, and it is evident that STLV-1 may play a role in the disease. Management practices in baboon colonies need to take into account the possible presence of STLV-1 and aim to reduce the transmission of the virus by preventing sexual contact between positive and negative animals. Lymphoma needs to be considered as one of the more common causes of wasting and death. 相似文献
Design and procedure The records of all animals that had died since establishment of the National Baboon Colony in Australia were reviewed retrospectively. The clinical signs and histopathological findings were recorded and assessed to determine the involvement of lymphoma in the deaths. The presence of STLV-1 was recorded if known and correlated with the STLV-1 status of the colony.
Results Of the deaths from disease or illness, 53% were diagnosed as or suspected to be lymphoma, occurring in mature animals with no sex predisposition. The most common presentation was rapidly occurring generalised lymphadenomegaly.
Conclusions This study has described a relatively high prevalence of lymphoma in a colony of captive-bred baboons, and it is evident that STLV-1 may play a role in the disease. Management practices in baboon colonies need to take into account the possible presence of STLV-1 and aim to reduce the transmission of the virus by preventing sexual contact between positive and negative animals. Lymphoma needs to be considered as one of the more common causes of wasting and death. 相似文献
629.
Board-invited review: the biology and regulation of preadipocytes and adipocytes in meat animals 总被引:2,自引:0,他引:2
Hausman GJ Dodson MV Ajuwon K Azain M Barnes KM Guan LL Jiang Z Poulos SP Sainz RD Smith S Spurlock M Novakofski J Fernyhough ME Bergen WG 《Journal of animal science》2009,87(4):1218-1246
The quality and value of the carcass in domestic meat animals are reflected in its protein and fat content. Preadipocytes and adipocytes are important in establishing the overall fatness of a carcass, as well as being the main contributors to the marbling component needed for consumer preference of meat products. Although some fat accumulation is essential, any excess fat that is deposited into adipose depots other than the marbling fraction is energetically unfavorable and reduces efficiency of production. Hence, this review is focused on current knowledge about the biology and regulation of the important cells of adipose tissue: preadipocytes and adipocytes. 相似文献
630.
Barnes LD Giuliano EA Ota J Cohn LA Moore CP 《Veterinary journal (London, England : 1997)》2009,180(1):60-65
Successful treatment of naturally occurring periocular squamous cell carcinoma (SCC) in horses with photodynamic therapy (PDT) has been performed by injecting residual tumor with verteporfin and applying laser irradiation immediately following injection. This study used a murine model to evaluate the influence of time between intralesional injection of verteporfin to laser irradiation on tumor growth inhibition with PDT. Mice were randomized into six groups (n=10/group). Each tumor was injected with either 0.1mg/cm(3) of verteporfin (Tx) or 5% dextrose in water (C). Tx and C groups 1, 2, and 3 were irradiated at 1, 30, and 180min after injection. Wilcoxon-rank sum test (P< or =0.05) was performed to determine the relative change in tumor volume (RCTV) between groups. Statistical significance was demonstrated between treatment groups. Although verteporfin-PDT treated mice in Tx1 and Tx2 demonstrated a lower RCTV compared to C1 and C2 mice, the differences were not statistically significant. 相似文献