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31.
ROBERT MARSH BRIAN PETRIE CHRISTOPHER R. WEIDMAN ROBERT R. DICKSON JOHN W. LODER CHARLES G. HANNAH KENNETH FRANK & KEN DRINKWATER 《Fisheries Oceanography》1999,8(1):39-49
A mass mortality of `warm-water' tilefish in the Middle Atlantic Bight between April and August of 1882 suggests an episode of extreme cold in the shelf waters off the north-eastern United States. This cooling is hypothesized to be a consequence of enhanced equatorwards transport of cold water in the Labrador Current, coincident with a minimum in the North Atlantic Oscillation (NAO) index during the early 1880s.
Although there is little direct evidence for this historical event, an analogue for the 1880s cooling is found in the 1960s, at the most recent NAO-index minimum. Post-1945 observations in the Middle Atlantic Bight / Gulf of Maine region reveal changes in winter baroclinic circulation between cool and warm decades, with greater equatorward penetration of south-westwards flow along the shelf-edge during the cool 1960s. Over the period 1934–77, the NAO is found to account for 17% of the interannual variance in Labrador Current transport around the Grand Banks.
Proxy evidence for the cold episode of the early 1880s is sought. Records of bottom temperature in the Middle Atlantic Bight region are reconstructed using stable oxygen isotopic analysis on the annual bands of shells of a bivalve mollusc ( Arctica islandica ) and an empirical model of covariability with local air temperature. The result is confirmation of the presence of anomalously cold water during the early 1880s. 相似文献
Although there is little direct evidence for this historical event, an analogue for the 1880s cooling is found in the 1960s, at the most recent NAO-index minimum. Post-1945 observations in the Middle Atlantic Bight / Gulf of Maine region reveal changes in winter baroclinic circulation between cool and warm decades, with greater equatorward penetration of south-westwards flow along the shelf-edge during the cool 1960s. Over the period 1934–77, the NAO is found to account for 17% of the interannual variance in Labrador Current transport around the Grand Banks.
Proxy evidence for the cold episode of the early 1880s is sought. Records of bottom temperature in the Middle Atlantic Bight region are reconstructed using stable oxygen isotopic analysis on the annual bands of shells of a bivalve mollusc ( Arctica islandica ) and an empirical model of covariability with local air temperature. The result is confirmation of the presence of anomalously cold water during the early 1880s. 相似文献
32.
CHIU-LONG CHOU LISA ANN PAON JOHN DANIEL MOFFATT BLAINE ZWICKER 《Fisheries Science》2003,69(2):369-378
ABSTRACT: Bioaccumulation and distribution of Mn and Zn in the total softtissues, digestive glands, residuals and adductor muscles of thehorse mussel Modiolus modiolus from three sites, includingindustrialized and non-industrialized locations in Eastern Canada,were investigated. Extremely high digestive gland metal concentrationswere found in individual mussels, as high as 1819 µg/gMn wet weight and 1964 µg/g Zn wet weight,with mean values from 358 to 404 µg/gMn and from 399 to 614 µg/g Zn for thecollection sites. High Mn to Zn interrelationships were observed inall types of tissues and at all sites. Between different tissues,Zn was interrelated by linear relationships, and Mn was best describedby power curve relationships for all tissue types. In the totalsoft tissue, Mn and Zn interrelations were fitted to power regressioncurves with different slopes between the three study sites. Thisindicated that horse mussel was exposed to different metal levels inthe environments and could be useful for monitoring these metals.The uptake of both metals at extremely high concentrations, thelack of regulation and the occurrence of interactions all suggest thatMn and Zn may play a biological role in horse mussels. Zn and Mninteractions, surprisingly, were not disrupted at the very highconcentrations of either metal, which proves that the mechanism ofmetal interactions does not involve a detoxification role. 相似文献
33.
34.
P. ROBIN PETERSON DVM JOHN R. PASCOE BVSC PhD JOHN D. WHEAT DVM DiplomateACVs 《Veterinary surgery : VS》1987,16(5):367-372
Fractures of Metacarpal and Metatarsal II and IV (the splint bones) were treated in 283 horses over an 11 year period. In 21 cases the proximal portion of the fractured bone was stabilized with metallic implants. One or more cortical bone screws were used in 11 horses, and bone plates were applied in 11 horses. One horse received both treatments. Complications of screw fixation included bone failure, implant failure, radiographic lucency around the screws, and proliferative new bone at the ostectomy site. Only two of the horses treated with screw fixation returned to their intended use. Complications of plate fixation included partial fixation failure (backing out of screws), wound drainage, and proliferative bony response around the plate. Six of the 11 horses treated by plate fixation returned to their intended use. The authors recommend consideration of plate fixation techniques for repair of fractures in the proximal third of the splint bone. 相似文献
35.
DAVID L. PANCIERA IAN D. DUNCAN ALBEE MESSING JOHN E. RUSH PATRICK A. TURSKI† 《The Journal of small animal practice》1987,28(7):587-596
Accurate localization of the lesions in two dogs with progressive neurological disease was demonstrated with magnetic resonance imaging (MRI). The first dog had unilateral cerebellar signs with associated paradoxical vestibular symptoms. The CSF tap and clinical localization suggested a right-sided cerebellar tumour and this was confirmed with MRI scanning. The second dog had predominantly asymmetrical fore-brain signs with circling, personality changes, seizures and contralateral proprioceptive deficits. CSF analysis suggested an inflammatory or neoplastic condition. MRI showed a diffuse oedematous lesion of the left cerebral hemisphere which corresponded exactly with the lesions seen at necropsy. The advantages of MRI over CT scans are discussed. 相似文献
36.
37.
CLIFFORD M. HONNAS DVM Dipiomate ACVS ROBERT D. WELCH DVM PhD Dipiomate ACVS TROY S. FORD DVM Dipiomate ACVS JOHN R. VACEK DVM JEFFREY P. WATKINS DVM MS Dipiomate ACVS 《Veterinary surgery : VS》1992,21(4):261-268
The medical records of 12 horses with septic arthritis of a distal interphalangeal joint were reviewed to determine clinical features and response to treatment. Sepsis was caused by trauma or an injection that resulted in an open or contaminated distal interphalangeal joint. All horses were severely lame. Treatment included broad-spectrum parenterally administered antimicrobial drugs (ten horses), percutaneous through-and-through joint lavage (eight horses), indwelling drains (three horses), immobilization of the limb in a cast (three horses), intraarticular injection of sodium hyaluronate (one horse), intraarticular injection of antimicrobial drugs (five horses), curettage of the distal phalanx (one horse), and cancellous bone grafting to promote fusion (one horse). Five horses were euthanatized. Ankylosis of the affected joint developed in five horses, four of which are pasture sound. Two horses treated medically are sound although one underwent subsequent palmar digital neurectomy for treatment of navicular syndrome. 相似文献
38.
PAUL W. MORGAN DVM DVSc ALLEN G. BINNINGTON DVM MSc Diplomate ACVS CRAIG W. MILLER DVM MVSc Diplomate ACVS DALE A. SMITH DVM DVSc ANNE VALLIANT BSc JOHN F. PRESCOTT MA Vet MB PhD 《Veterinary surgery : VS》1994,23(6):494-502
This project compared the effects of hydrocolloid (HC) and hydrogel (HG) occlusive dressings and a polyethylene (PE) semi-occlusive dressing on the healing of acute full-thickness skin wounds on the forelimbs of 10 dogs. All treatments resulted in a similar degree of healing at postoperative days 4 and 7. No significant differences existed in the number of wounds that were more than 90% healed at postoperative day 28 between the group treated with the HG dressing and the group treated with the PE dressing. There were significantly fewer wounds more than 90% healed at postoperative day 28 in the group treated with the HC dressing. Wounds under the HG dressing had the largest mean percentage of contraction at postoperative days 21 and 28. Wounds under the HG dressing also had the largest contraction/re-epithelialization ratio (postoperative days 21 and 28) compared with wounds under the PE and HC dressings. Wounds under the PE dressing had a significantly higher mean percentage of re-epithelialization than wounds under both occlusive dressings on postoperative days 14, 21, and 28. Wounds under the two occlusive dressings had exuberant granulation tissue present more often than wounds under the PE dressing. The two occlusive dressings had significantly higher bacterial counts on wounds compared with wounds under the PE dressing; analysis of variance (ANOVA), P = .0008. Wounds under the HC dressing showed the poorest healing in all parameters. 相似文献
39.
CHARLES M. WALLS DVM CLARE R. GREGORY DVM Diplomate ACVS L. STEVEN BECK DVM JOHN P. COOKE MD PhD STEPHEN M. GRIFFEY DVM PHIL H. KASS DVM PhD 《Veterinary surgery : VS》1995,24(6):484-491
This study determined the effect of the polypeptide growth factors transforming growth factor-beta (TGF-β), insulin-like growth factor-I (IGF-I), and growth hormone (GH) alone and in combination with dietary L-Arginine HCL (ARG) on skin flap survival in rats. Caudally based dorsal skin flaps were created in 110 Sprague-Dawley rats. The rats were randomly assigned into three treatment groups, based on drinking water supplementation. Group 1 (n = 50) received ARG in their drinking water, group 2 (n = 50) received tap water alone, and group 3 (n = 10) received N-omega-nitro-L-arginine (L-NA) and hydralazine. Groups 1 and 2 were divided into subgroups of 10 rats each based on treatment with either: TGF-β, IGF-I, GH, or IGF-I + GH. All subgroups that received GH had significantly greater ( P <.0001) median body weight gains when compared with subgroups not receiving GH. L-arginine HCL when added to IGF-I negated the positive effects of IGF-I on both flap survival and weight gain. Although the rats in all subgroups from groups 1 and 2 had an increase in mean percent skin flap survival when compared with the water alone subgroup, only rats receiving IGF-I, or the combination of ARG with either TGF-β or GH, had statistically significant enhanced skin flap survival. Rats in group 3 did not show an increase in skin flap survival when compared with the control subgroup. 相似文献
40.