The Economic Effects of Land Value Taxation—Comment     

DONALD A. COFFIN  MICHAEL A. NELSON 《Growth and change》1983,14(3):44-46

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Competitiveness Policy Options: The Technology-Regions Connection     

MICHAEL STORPER 《Growth and change》1995,26(2):285-308

ABSTRACT Competitiveness can be defined as the ability of an economy to maintain stable or increasing market shares in an economic activity while sustaining stable or increasing living shares for those who participate in it. Government policy in all countries has strong effects on competitiveness. With the turn away from a Cold War economy the Clinton Administration has pursued a technology policy explicitly linked to the quest for heightened national competitiveness. It is based on a rejection of Reagan-Bush era analyses of the competitiveness problem, which centered on cost reduction in industry. There are many different forms of technology policy for competitiveness, however. Some center on labor quality, while others center on technological spillovers between industries. An effective policy should promote technological spillovers in the economy. All such policies, moreover, are only effective if they are organized and governed properly. The Clinton-Gore policy has many different programs and methods of governance. This paper argues that it should reinforce the regional level of organization of technology policy formulation and implementation.  相似文献   

"Hypersexuality" in male cats without brain damage     

MICHAEL RP 《Science (New York, N.Y.)》1961,134(3478):553-554

During 5 years of observation in a cat colony where mating tests are routinely conducted, the spontaneous occurrence of distortions of sexual activity in male cats has been recorded. Many of the behavioral patterns encountered have previously been described only in brain-damaged animals when they have been used as an index of "hypersexuality." Identical behavior occurs in normal males as a simple training effect.  相似文献   

POSITIVE CONTRAST MAGNETIC RESONANCE BURSOGRAPHY FOR ASSESSMENT OF THE NAVICULAR BURSA AND SURROUNDING SOFT TISSUES     

MICHAEL C. MAHER  NATASHA M. WERPY  LAURIE R. GOODRICH  C. WAYNE McIlWRAITH 《Veterinary radiology & ultrasound》2011,52(4):385-393

Magnetic resonance (MR) imaging is often performed to determine the cause of palmar heel pain. We evaluated how distension of the navicular bursa affected the MR appearance of the navicular bursa and associated structures. An MR evaluation was performed on normal cadaver limbs and cadaver limbs from horses with lameness localized to the foot. The normal navicular bursae were injected with 2, 4, or 6 ml of solution. The bursae of the feet from lame horses were injected with 4 or 6 ml, and the MR study was repeated. All bursae were examined grossly to verify the presence or absence of adhesions. Clinical patients that had initial MRI abnormalities suggesting adhesions were also evaluated. Distension of the proximal recess of the normal navicular bursa, proximal to the collateral sesamoidean ligament was achieved with 2 ml. Separation of the collateral sesamoidian ligament from the deep digital flexor tendon (DDFT) was achieved with 4 ml. The separation of the navicular bone from the DDFT and distal sesamoidian impar ligament required 6 ml. Adhesions were more clearly defined in the bursa of the two pathologic cadaver limbs following distension. MR bursography used on clinical patients allowed the determination of the presence or absence of adhesions. In these horses, this determination could not have been definitively made without this technique. MR bursography is useful in horses where the presence of adhesions cannot be clearly defined by MRI.  相似文献   

CLINICAL RELEVANCE OF ABNORMAL SCINTIGRAPHIC FINDINGS OF ADULT EQUINE RIBS     

JESSICA A. DAHLBERG  MICHAEL W. ROSS  BENSON B. MARTIN  ELIZABETH J. DAVIDSON  MIDGE LEITCH 《Veterinary radiology & ultrasound》2011,52(5):573-579

Horses with cranial rib abnormalities may exhibit severe acute lameness and may have unusual gait deficits characterized by forelimb abduction during protraction at the walk. Horses with caudal rib abnormalities may resent being saddled and ridden. In a retrospective evaluation of 20 horses with a documented rib lesion, 25 sites of increased radiopharmaceutical uptake were found in one or more ribs. Thirteen (52%) scintigraphic lesions involved the first rib; four were located immediately dorsal to the sternal articulation, eight were near the costochondral junction and one was at the costovertebral junction. Six (24%) scintigraphic rib lesions involved ribs 2–8; one was located immediately dorsal to the sternal articulation, three were at the costovertebral junction and two were near the costochondral junction. Six (24%) scintigraphic rib lesions involved the mid‐portion (five) or costovertebral junction (one) of ribs 9–18. The 20 horses were divided into three groups based on the clinical relevance of the scintigraphic findings. Group 1 (n=3) horses had clinical signs attributed to a rib abnormality; Group 2 (n=6) horses had a rib abnormality that was a plausible explanation for clinical signs; Group 3 (n=11) horses had clinical signs that could not be attributed to a rib abnormality. For horses with cranial rib abnormalities, a modified lateral scintigraphic image with the ipsilateral limb pulled caudally and a left (right) 45° caudal–right (left) radiograph facilitated the diagnosis.  相似文献   

DETERMINATION OF T1 RELAXATION TIME OF NORMAL EQUINE TENDONS USING MAGIC ANGLE MAGNETIC RESONANCE IMAGING     

MATHIEU SPRIET  ERIK R. WISNER  LUCY A. ANTHENILL  MICHAEL H. BUONOCORE 《Veterinary radiology & ultrasound》2011,52(2):149-153

Seven isolated equine front limbs were used to establish the normal T1 relaxation time of equine superficial digital flexor tendon (SDFT), deep digital flexor tendon (DDFT), and suspensory ligament (SL) using magic angle magnetic resonance (MR) imaging. MR imaging of the metacarpi was performed with the limbs positioned at 55° (the magic angle) relative to the main magnetic field. Transverse spin‐echo proton density and inversion recovery images were acquired. T1 relaxation time was calculated based on ratios of signal intensity determined from the different pulse sequences. T1 relaxation times for SDFT, DDFT, and SL were 288 (±17), 244 (±14), and 349 (±16) ms, respectively. The difference in T1 values between SDFT, DDFT, and SL was statistically significant. T1 values of equine tendons can be determined with magic angle imaging on a clinical MR system using <10 min total scan time. The knowledge of the normal range of T1 values may be useful to identify horses with chronic tendinopathy, where based on the human literature, an increased T1 value may be expected.  相似文献   

COMPUTED TOMOGRAPHIC EVALUATION OF ANATOMIC AND PATHOLOGIC VARIATIONS IN THE FELINE NASAL SEPTUM AND PARANASAL SINUSES     

JENNIFER A. REETZ  WILFRIED MAÏ  KATE B. MURAVNICK  MICHAEL H. GOLDSCHMIDT  TOBIAS SCHWARZ 《Veterinary radiology & ultrasound》2006,47(4):321-327

The purpose of this study was to compare the prevalence of nasal septal deviation and variations of the paranasal sinuses in normal and diseased cats. Prevalence of nasal septal deviation was 86.7%, 68.4%, and 71.4% in cats with rhinitis, neoplasia, and normal cats, respectively, with no statistically significant difference (P = 0.244). There was a statistically significant difference (P = 0.01) in the magnitude of nasal septal deviation between cats with and cats without nasal disease, using a cutoff value of 1 mm for maximum distance of deviation from midline. There was a statistically significant difference (P = 0.019) between cats with rhinitis and neoplasia when comparing the presence of a mass (7.7% and 53.8%, respectively), but not when comparing for lysis of the septum. Deviation of the frontal sinus septum occurred in 27.7% of all cats, while the sphenoid septum was oblique and eccentric in 96.6% of all cats. The mean length of the frontal sinus was longer in male cats than female cats. The presence of nasal septal deviation alone cannot be used as a criterion to diagnose nasal disease, but cats with rhinitis or neoplasia have more marked deviation than normal cats. The presence of a mass and lysis of the septum were only seen in cats with nasal disease and a mass is more likely to be seen with neoplasia than rhinitis. Male cats have a longer frontal sinus than female cats. Almost all cats have an oblique, eccentric sphenoid septum.  相似文献   

Complications of Celiotomy Incisions in Horses     

DAVID A. WILSON DVM  MS  Diplomate ACVS    GORDON J. BAKER BVSc  PhD  MRCVS  Diplomate ACVS  MICHAEL J. BOERO DVM  MS  Diplomate ACVS 《Veterinary surgery : VS》1995,24(6):506-514

Complications of celiotomy incisions were evaluated retrospectively in 274 horses that survived at least 1 month after surgery, or died or were euthanatized within 1 month of surgery, as a direct result of these complications. Horses were divided into four groups; group A, a ventral median celiotomy for intestinal disease; group B, ventral median celiotomy for nonintestinal disease; group C, repair of an umbilical hernia; and group D, celiotomy in a region other than the midline. Specific incisional complications were peri-incisional edema, drainage, incisional abscess, suture sinus, and dehiscence. Incision-related complications occurred in 30% of the horses (group A, 40%; group B 18%; group C, 7%; and group D, 88%). Complications occurred more frequently in group D than group A ( P =.009), which were higher than in groups B and C ( P <.00001). Incisional hernia occurred in 28 of 256 (11%) horses that survived at least 4 months and were available for follow-up. Hernia formation was more common ( P <.00001) in horses that had other incisional complications (23 horses) than those without (5 horses). Serous or purulent incisional drainage, were more likely to be associated with hernia formation than was serosanguineous drainage or other incisional complications.  相似文献   

The Effects of Fixation of the Ulna to the Radius in Young Foals   总被引：1，自引：0，他引：1  

MICHAEL F. CLEM DVM  MS    RICHARD M. DeBOWES DVM  MS  Diplomateacvs    JAMES P. DOUGLASS DVM  MS  Diplomateacvr    HORST W. LEIPOLD DrMedVet  PhD  JAMES A. CHALMAN DVM 《Veterinary surgery : VS》1988,17(6):338-345

The effects of radioulnar fixation were studied in 21 Quarter horse foals by applying a bone plate to the caudal aspect of the proximal part of the ulna, with screws engaging both the radius and the ulna. The plates were applied at 1 month of age in six foals (group I), 5 months of age in six foals (group II), and 7 months of age in three foals (group III). Six foals underwent sham operations at 1 month of age to serve as controls (group IV). Ulnar dysplasia and elbow subluxation developed in all treated foals. The magnitude of ulnar dysplasia was inversely related to the patient's age at fixation and was accompanied by degenerative joint disease and lameness in foals undergoing fixation at 1 and 5 months of age. Removal of the fixation appliances 16 weeks after implantation in three foals from each of groups I and II failed to reverse the degree of ulnar dysplasia. Although foals undergoing fixation at 7 months of age (group III) were not lame, radiographic evidence of subluxation and subtle degenerative changes in the articular cartilage of the treated elbow did develop. Recommendations for avoidance of radioulnar fixation were developed from these observations.  相似文献   

Long-Term Follow-up of Partial Limb Amputation in 13 Horses   总被引：1，自引：0，他引：1  

GREGORY R. CRAWLEY DVM  MS    BARRIE D. GRANT DVM  MS  DiplomateACVs    MELINDA K. KRPAN DVM  MS  MICHAEL D. MAJOR DVM 《Veterinary surgery : VS》1989,18(1):52-55

Thirteen cases of partial limb amputation in horses were reviewed. Nine horses (69%) survived 18 to 111 months (mean, 41 months). Four unsuccessfully treated horses were euthanatized within 21 days of surgery. The horses' ages at amputation were 4 to 13 years (mean, 7.3 years). There was no predilection for the left or right limb nor for fore or hind limb involvement. Osteomyelitis in six horses (46%) was the most common cause for amputation. Severe, open, comminuted fractures of the third metacarpal bone that were impossible to stabilize by any currently available technique in four horses (31%) were the second most common cause for amputation. One gelding was salvaged because of his sentimental value, two horses were used as breeding stallions, and six were broodmares. One stallion lived 30 months, completed two breeding seasons, and started a third. The other stallion began breeding, but became sterile. Three of the mares have produced five foals. One mare died while in foal. One mare aborted near-term twin fetuses and died of uterine hemorrhage. One mare aborted twice before the femoral head ligament on the contralateral limb ruptured, and she was euthanatized.  相似文献