Incidence of post-anaesthetic arrhythmias in the dog

A total of 50 dogs, judged to be free of cardiovascular disease on the basis of physical and electrocardiographic (ECG) examination, underwent ECG monitoring during recovery from general anaesthesia. Fifteen of these dogs (30 per cent) developed some form of cardiac arrhythmia during the recovery period. The arrhythmias most frequently observed were premature ventricular contractions and atrioventricular conduction defects of varying degrees of severity. The observed arrhythmias had ceased by the end of the observation period and did not require specific therapy. There was no apparent correlation between the duration of anaesthesia, the type of medical or surgical procedure and the development of arrhythmias. However, the dogs developing arrhythmias were older than those that did not. The relatively high frequency of occurrence of cardiac arrhythmias must be considered in the evaluation of ECG data from dogs being monitored during recovery from anaesthesia.     

Are Business Services Immune to the Business Cycle?

Should an economic development strategy target the business services industry to insulate the local economy from the business cycle? The relationship between business services employment (SIC 73) and measures of the business cycle is analyzed at national and metropolitan-area levels. At the national level, certain components of business services are not immune to the business cycle while others are. At the metropolitan level, certain characteristics of the metropolitan area and its industrial structure are identified which would result in business services employment being procyclical or not immune to the business cycle.     

The View from Washington

The case against a gross state product series is presented by the Associate Director for Regional Economic Analysis of the Commerce Department's Office of Business Economics (which recently changed its name to the Bureau of Economic Analysis). Dr. Graham, the newest member of this journal's editorial board, also provides some glimpses into the kitchen where his office is preparing new data morsels for regional economists.     

Tenoscopic Anatomy of the Equine Carpal Flexor Synovial Sheath

Objective —To describe the tenoscopic anatomy of the carpal sheath of the flexor tendons (carpal sheath) viewed from a lateral approach.
Study Design —Tenoscopic observation of structures within the carpal sheath subsequently confirmed by dissection.
Animals or Sample Population—12 equine cadaveric forelimbs.
Methods —The limbs were positioned lateral side up with the carpus slightly flexed. After distention of the carpal sheath, a portal for the arthroscope was made approximately 3 cm proximal to the distal radial physis and 2.5 cm caudal to the radius between the tendons of the ulnaris lateralis and lateral digital extensor muscles.
Results —A lateral tenoscopic approach was adequate to identify all structures within the carpal sheath. From proximal to distal, structures identified using this approach were the radial head of the deep digital flexor muscle, accessory ligament of the tendon of the superficial digital flexor muscle, distal radial physis, tendons of the superficial and deep digital flexor muscles, accessory carpal bone, antebrachiocarpal and middle carpal joints, and vincula of the tendon of the deep digital flexor muscle.
Conclusions —A lateral tenoscopic approach offered an easy, repeatable entry into the carpal sheath and allowed good observation of all structures within the sheath except for the medial borders of the tendons of the deep and superficial digital flexor muscles.
Clinical Relevance —Applications of a lateral tenoscopic approach to the carpal sheath include diagnostic procedures, lavage and synovial resection for septic tenosynovitis, desmotomy of the accessory ligament of the tendon of the superficial digital flexor muscle for flexural deformity or tendinitis, and removal of osteochondromas from the distal radial metaphysis.     

FLUORIDE ADSORPTION BY ILLINOIS SOILS

Fourteen surface and 6 subsurface horizons of Illinois soils adsorbed significant amounts of F^? with release of OH^?. At low concentrations, adsorption was described by both Langmuir and Freundlich isotherms. The calculated Langmuir adsorption capacities were related to pH, clay, organic carbon, and amorphous aluminum contents. Two soils with different gross chemical properties behaved in essentially the same manner, with adsorption maxima occuring between pH 5.5 and 6.5. The similarity between adsorption at different pH values for the soils and those for bauxite, allophane and synthesized ‘soil chlorite’, and the lack of adsorption maxima between pH 5.5 and 6.5 for pure kaolinite and montmorillonite, suggest that F^? adsorption in the soils is due primarily to the presence of amorphous aluminum oxyhydroxides which are common weathering products in these soils.     

Reduced herbicide doses in field crops: A review

Farmers are becoming increasingly interested in more comprehensive weed management programs that reduce weed populations over time and in the use of reduced herbicide doses that lower their production costs. Research indicates that there is good potential to reduce the number of herbicide applications and utilize lower herbicide doses within competitive cropping systems. Diverse crop rotations, competitive cultivars, higher crop seed rates, reduced row spacing, specific fertilizer placement, and cover crops have been identified as integral components of competitive cropping systems. This review paper explores the potential for successful use of reduced herbicide doses within competitive cropping systems that have a multiyear approach to weed management. The utilization of decision support systems or new methods of assessing active weed growth are discussed in light of further enhancing the successful use of reduced herbicide doses and advising farmers on when (and when not) they might be a viable option.