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41.
Many rural hierarchies are becoming increasingly dominated by a few regional growth centers while the retail sector in adjacent smaller communities either stagnates or declines. This study tests the hypothesis that the rate of adjustment of the retail sector to changing consumer spending patterns is uniform across different ordered communities in a rural hierarchy. Neoclassical investment theory is combined with central place theory to develop a conceptual model of the relationship between the retail sector and investment in a community. A three tiered 49 community hierarchy is constructed using data from the Minnesota Department of Revenue and the Report of Condition and Income of the Board of Governors of the Federal Reserve System. A crosssectional time series ordinary least squares regression model is employed to estimate retail coefficients of adjustment for the hypothesis testing. Regional estimates indicate only partial adjustment in the retail sector across the whole hierarchy to shifts in consumer spending patterns. Community estimates, which decompose the regional estimate, indicate retail businesses in the largest and mid-sized communities adjust totally in one period, but that retail businesses in the smallest communities do not. The faster rates of adjustment by retail businesses in the larger communities to changing consumer spending patterns may augment the development of regional growth centers in rural areas. 相似文献
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Marine environment of the eastern and central Aleutian Islands 总被引:2,自引:0,他引:2
43.
GEORGE A. HENRY DVM CLARK S. PATTON DVM MS DALLAS O. GOBLE DVM 《Veterinary radiology & ultrasound》1986,27(5):132-140
Iatrogenic lesions to the accessory ligament (carpal check or inferior check) and to the superficial digital flexor tendon of five ponies were monitored utilizing diagnostic ultrasound for a period of 6–24 weeks post-injury. The opposite limb was used as a non-surgical control. Sonographic differences from control limbs were recorded and correlated with the gross and microscopic post-mortem lesions. Early post-surgical sonographic findings included thickening with discrete hypoechoic areas within the injured tissues which corresponded to regions of hemorrhage, edema, and tissue disruption at necropsy. The linear hyperechoic pattern seen in normal tendons was disorganized in the injured portion of the tendons or ligaments. Disruption of the margins of the incised tissues was observed. The initial hypoechoic areas disappeared or decreased in size and became more echoic as healing progressed. The increasing echoic pattern in these areas corresponded to regions of fibrous tissues invasion and collagen deposition. As post-injury time increased, the size of the tendon or ligament decreased, the margins became more distinct, and the internal structure again became more organized (linear). It was concluded that diagnostic ultrasound can be useful in evaluating injury and healing of the accessory ligament and the superficial digital flexor tendon of horses. 相似文献
44.
GEORGE VOORHOUT DVM HERMAN A. W. HAZEWINKEL DVM PHD 《Veterinary radiology & ultrasound》1987,28(5):158-165
The results of radiographic examination of clinically affected elbow joints in 14 young, large-breed dogs, including standard and oblique projections and linear tomography, were compared with the findings of medial arthrotomy. Radiographs revealed arthrosis (13 dogs), osteochondrosis of the medial humeral condyle (2 dogs), fragmentation of the medial coronoid process (5 dogs), and a combination of osteochondrosis of the medial humeral condyle and fragmentation of the medial coronoid process (2 dogs). In one dog fissures in the medial coronoid process and in another dog a linear radiopacity along the articular surface of the medial coronoid process were found. In three dogs both medial humeral condyle and medial coronoid process appeared normal. The radiographic findings were confirmed during surgery in 11 dogs. Cartilage erosion of the medial humeral condyle in two dogs and of the medial coronoid process in one dog had not resulted in radiographically visible abnormalities. Radiographic examination of the elbow joints in young, large-breed dogs should include standard mediolateral and craniocaudal projections, a mediolateral projection with the joint maximally extended and the leg supinated 15°, and a craniolateral-to-caudomedial projection. 相似文献
45.
SHARON C. KERWIN dvm GISELLE HOSGOOD bvsc ms facvsc dipiomate acvs GEORGE M. STRAIN phd CAROL C. VICE dvm CLAUDE E. WHITE dvm R. KELLY HILL mo facm 《Veterinary surgery : VS》1993,22(1):31-36
A pedicle skin flap based on the caudal superficial epigastric artery was created in 12 cats. The artery was ligated and the vein left intact. Six cats were treated with hyperbaric oxygen at 2 atm absolute for 90 minutes daily for 14 days, starting the day after surgery. Skin flap color was significantly better in the treated cats on days 1, 2, and 3. The amount of exudate was significantly less in the treated cats on day 3. There was no difference in the amount of swelling between treated and nontreated control cats. Although five of six of the treated cats had 100% skin flap survival, there was no significant difference in total flap survival between treated and nontreated control cats. 相似文献
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The Effect of Trans-Stifle External Skeletal Fixation and Hyaluronic Acid Therapy on Articular Cartilage in the Dog 总被引:8,自引:0,他引:8
WILLARD G. KELLER dvm DENNIS N. ARON dvm Dipiomate acvs GEORGE N. ROWLAND DVM PhD STEWART ODEND'HAL dvm PhD JOHN BROWN dvm PhD 《Veterinary surgery : VS》1994,23(2):119-128
Transarticular external skeletal (TES) fixators were applied unilaterally to the stifle joints of 10 young adult dogs. After 4 weeks, the fixators were removed from all dogs. Two dogs were not allowed a remobilization period, whereas 8 dogs were provided with 4 additional weeks of weight-bearing activity in a kennel run. Four dogs were given high-molecular weight hyaluronic acid by intra-articular injection weekly during the remobilization period. Clinical gait evaluations and range of motion were determined during the remobilization period. Articular cartilage samples from both stifle joints of all dogs were evaluated histologically and histochemically. No significant differences in gait scores or range of motion were noted between treated and untreated dogs. Articular cartilage proteoglycan content was reduced after 4 weeks of trans-stifle external skeletal fixation as determined by loss of alcian blue (AB) histochemical staining. Improved homogeneity of histochemical staining was observed after remobilization. However, remobilization was associated with histological damage to the surface and tangential layers of articular cartilage. Remobilization combined with hyaluronic acid (HA) therapy improved histochemical staining and reduced structural damage to articular cartilage when compared with remobilization alone. 相似文献
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