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141.
Stoneham AE Graham J Rozanski EA Rush JE 《Journal of the American Animal Hospital Association》2006,42(6):457-461
A 4-year-old, late-term pregnant Himalayan queen was diagnosed with biventricular congestive heart failure characterized by pleural effusion and pulmonary edema. A cesarean section was performed, resulting in the birth of four live kittens, with one surviving to discharge. Congestive heart failure resolved rapidly following surgery. The queen remained asymptomatic for 9 years postoperatively. Volume expansion secondary to pregnancy was thought to result in cardiovascular volume overload and subsequent congestive heart failure. 相似文献
142.
OBJECTIVE: To document simple and reliable local, infiltrating nerve blocks for the saphenous, tibial and common peroneal nerves in the dog. STUDY DESIGN: Laboratory technique development; in vivo blind, controlled, prospective study. ANIMALS: Twenty canine cadavers and 18 clinically normal, client-owned dogs. METHODS: A peripheral nerve blockade technique of the tibial, common peroneal, and saphenous nerves was perfected through anatomic dissection. Injections were planned in the caudal thigh for the tibial and common peroneal nerves, and in the medial thigh for the saphenous nerve. Cadaver limbs were injected with methylene blue dye and subsequently dissected to confirm successful dye placement. Clinically normal dogs undergoing general anesthesia for unrelated, elective procedures were randomly assigned to treatment (bupivacaine; n = 8) or control (saline; n = 8) nerve blocks of the nerves under study. Upon recovery from general anesthesia, skin sensation in selected dermatomes was evaluated for 24 hours. RESULTS: Cadaver tibial, common peroneal, and saphenous perineural infiltrations were successful in nonchondrodystrophoid dogs (100, 100, and 97%, respectively.) Intraneural injection was rare (1%; 1/105; tibial nerve) in cadaver dogs. In the treatment group of normal dogs, duration of loss of cutaneous sensation in some dermatomes (saphenous, superficial and deep peroneal nerve) was significantly different than control dogs; the range of desensitization occurred for 1-20 hours. No clinical morbidity was detected. CONCLUSIONS: This technique for local blockade of the tibial, common peroneal, and saphenous nerves just proximal to the stifle is easy to perform, requires minimal supplies and results in significant desensitization of the associated dermatomes in clinically normal, nonchondrodystrophoid dogs. CLINICAL RELEVANCE: This technique may be an effective tool for post-operative analgesia to the femoro-tibial joint and distal pelvic limb. Other applications, using sustained-release drugs or methods, may include anesthesia/analgesia in high-risk patients or as a treatment for chronic pelvic limb pain or self-mutilation. 相似文献
143.
144.
Keller LP Bajt S Baratta GA Borg J Bradley JP Brownlee DE Busemann H Brucato JR Burchell M Colangeli L d'Hendecourt L Djouadi Z Ferrini G Flynn G Franchi IA Fries M Grady MM Graham GA Grossemy F Kearsley A Matrajt G Nakamura-Messenger K Mennella V Nittler L Palumbo ME Stadermann FJ Tsou P Rotundi A Sandford SA Snead C Steele A Wooden D Zolensky M 《Science (New York, N.Y.)》2006,314(5806):1728-1731
Infrared spectra of material captured from comet 81P/Wild 2 by the Stardust spacecraft reveal indigenous aliphatic hydrocarbons similar to those in interplanetary dust particles thought to be derived from comets, but with longer chain lengths than those observed in the diffuse interstellar medium. Similarly, the Stardust samples contain abundant amorphous silicates in addition to crystalline silicates such as olivine and pyroxene. The presence of crystalline silicates in Wild 2 is consistent with mixing of solar system and interstellar matter. No hydrous silicates or carbonate minerals were detected, which suggests a lack of aqueous processing of Wild 2 dust. 相似文献
145.
Hörz F Bastien R Borg J Bradley JP Bridges JC Brownlee DE Burchell MJ Chi M Cintala MJ Dai ZR Djouadi Z Dominguez G Economou TE Fairey SA Floss C Franchi IA Graham GA Green SF Heck P Hoppe P Huth J Ishii H Kearsley AT Kissel J Leitner J Leroux H Marhas K Messenger K Schwandt CS See TH Snead C Stadermann FJ Stephan T Stroud R Teslich N Trigo-Rodríguez JM Tuzzolino AJ Troadec D Tsou P Warren J Westphal A Wozniakiewicz P Wright I Zinner E 《Science (New York, N.Y.)》2006,314(5806):1716-1719
Particles emanating from comet 81P/Wild 2 collided with the Stardust spacecraft at 6.1 kilometers per second, producing hypervelocity impact features on the collector surfaces that were returned to Earth. The morphologies of these surprisingly diverse features were created by particles varying from dense mineral grains to loosely bound, polymineralic aggregates ranging from tens of nanometers to hundreds of micrometers in size. The cumulative size distribution of Wild 2 dust is shallower than that of comet Halley, yet steeper than that of comet Grigg-Skjellerup. 相似文献
146.
We determine paleoelevation of the Sierra Nevada, California, by tracking the effect of topography on precipitation, as recorded in hydrogen isotopes of kaolinite exposed in gold-bearing river deposits from the Eocene Yuba River. The data, compared with the modern isotopic composition of precipitation, show that about 40 to 50 million years ago the Sierra Nevada stood tall (>/=2200 meters), a result in conflict with proposed young surface uplift by tectonic and climatic forcing but consistent with the Sierra Nevada representing the edge of a pre-Eocene continental plateau. 相似文献
147.
Franklin Behlau Blanca I. Canteros Jeffrey B. Jones James H. Graham 《European journal of plant pathology / European Foundation for Plant Pathology》2012,133(4):949-963
Genetic exchange is considered to be an important process in the selective adaptation of microorganisms to shifting and challenging environmental conditions. As a consequence of the copious use of copper bactericides, many species of plant pathogenic bacteria, including Xanthomonas citri subsp. citri (Xcc), have developed resistance to copper. This study assesses whether copper resistant (CuR) strains of other Xanthomonas species and citrus epiphytic bacteria pose a risk for the development of copper resistance in Xcc. CuR epiphytic bacteria were isolated on MGY agar from citrus leaves collected in two citrus groves treated with copper bactericides in Florida. Horizontal gene transfer of copper resistance genes was investigated within different Xanthomonas species and from citrus epiphytic bacteria to Xanthomonas. CuR epiphytic bacteria from citrus were screened for the presence of copper resistance genes homologous to copL, copA and copB genes from Xcc and characterized regarding tolerance to copper. Copper resistance determinants from a citrus epiphytic strain of Stenotrophomonas maltophilia (Stm) were cloned and expressed in Xcc and other Xanthomonas strains. Copper resistance genes in Xcc were determined to be present on a large (~300?kb) conjugative plasmid. Cu resistance was transferred via conjugation from two copper resistant citrus strains, Xcc and X. alfalfae subsp. citrumelonis (Xac), and two tomato pathogens, X. euvesicatoria (Xe) and X. perforans (Xp), to Xcc. PCR analysis revealed that two CuR strains from citrus, an epiphytic Xanthomonas ssp. and a strain of Stm, harboured homologs of the copper resistance genes found in CuR Xcc. The introduction of copLAB gene cluster from Stm into different xanthomonads conferred copper resistance to sensitive strains of Xcc, Xac, Xe and Xp. Based on these results there is a low, but significant, likelihood of horizontal gene transfer of copper resistance genes from other xanthomonads or epiphytic bacteria to Xcc in nature. 相似文献
148.
Lopez N Graham DJ McGuire R Alliger GE Shao-Horn Y Cummins CC Nocera DG 《Science (New York, N.Y.)》2012,335(6067):450-453
Generation of soluble sources of peroxide dianion (O(2)(2-)) is a challenge in dioxygen chemistry. The oxidizing nature of this anion renders its stabilization in organic media difficult. This Report describes the chemically reversible reduction of oxygen (O(2)) to cryptand-encapsulated O(2)(2-). The dianion is stabilized by strong hydrogen bonds to N-H groups from the hexacarboxamide cryptand. Analogous stabilization of peroxide by hydrogen bonding has been invoked recently in crystalline saccharide and protein systems. The present peroxide adducts are stable at room temperature in dimethyl sulfoxide (DMSO) and N,N'-dimethylformamide (DMF). These adducts can be obtained in gram quantities from the cryptand-driven disproportionation reaction of potassium superoxide (KO(2)) at room temperature. 相似文献
149.
Soon FF Ng LM Zhou XE West GM Kovach A Tan MH Suino-Powell KM He Y Xu Y Chalmers MJ Brunzelle JS Zhang H Yang H Jiang H Li J Yong EL Cutler S Zhu JK Griffin PR Melcher K Xu HE 《Science (New York, N.Y.)》2012,335(6064):85-88
Abscisic acid (ABA) is an essential hormone for plants to survive environmental stresses. At the center of the ABA signaling network is a subfamily of type 2C protein phosphatases (PP2Cs), which form exclusive interactions with ABA receptors and subfamily 2 Snfl-related kinase (SnRK2s). Here, we report a SnRK2-PP2C complex structure, which reveals marked similarity in PP2C recognition by SnRK2 and ABA receptors. In the complex, the kinase activation loop docks into the active site of PP2C, while the conserved ABA-sensing tryptophan of PP2C inserts into the kinase catalytic cleft, thus mimicking receptor-PP2C interactions. These structural results provide a simple mechanism that directly couples ABA binding to SnRK2 kinase activation and highlight a new paradigm of kinase-phosphatase regulation through mutual packing of their catalytic sites. 相似文献
150.
IW Tenaya K Heel PA Stumbles GE Wilcox 《Veterinary immunology and immunopathology》2012,149(3-4):167-176
Jembrana disease virus (JDV) is an unusual bovine lentivirus that causes an acute and sometimes fatal disease after a short incubation period in Bali cattle (Bos javanicus). The pathological changes occur primarily in lymphoid tissues, which feature proliferating lymphoblastoid-like cells predominantly throughout parafollicular (T-cell) areas, and atrophy of follicles (B-cell) areas. Five Bali cattle were experimentally infected with JDV and all developed typical clinical signs of Jembrana disease characterised by a transient febrile response, enlargement of superficial lymph nodes and a significant leukopenia. Flow cytometric analysis of PBMC during the acute (febrile) disease phase showed that the reduced number of lymphocytes was due to a significant decrease in both the proportion and absolute numbers of CD4(+) T cells, but not CD8(+) T-cells or CD21(+) B-cells. At the end of the febrile phase, total numbers of both CD8(+) T-cells and CD21(+) B-cells increased significantly, while CD4(+) T-cell numbers remained below normal values, resulting in a significantly reduced CD4(+):CD8(+) ratio. We speculate that the persistent depletion of CD4(+) T cells following JDV infection, through lack of CD4(+) T cell help to B cells, may explain the lack of production of JDV-specific antibodies for several weeks after recovery despite an increase in CD21(+) B cell numbers. Further, our previous data showing that IgG(+) plasma cells are targets for JDV infection, correlated with our current data demonstrating an increase in CD8(+) T cell numbers, supports the suggestion that anti-viral cytotoxic T cell or other cell-mediated immune responses may be critical in the recovery process, although this remains to be formally demonstrated for JDV. 相似文献