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91.
A technique for rapidly separating platelets from small quantities of whole blood is described. The isolation method allowed for counting and sizing platelets by electronic means, and counts with this new method were closely correlated with those obtained by phase microscopy. Platelet sizing was possible because of the inert and isotonic nature of the density-gradient medium used in the procedure. The technique was applicable to samples of blood from persons, horses, cattle, sheep, goats, pigs, dogs, mice, rats, guinea pigs, and rabbits. The isolation of platelets from whole blood of various species of animals was necessary for electronic counting because of the great variation in sizes of platelets and erythrocytes and the variable sedimentation properties of animal blood.  相似文献   
92.
Thirteen dogs with fractures requiring surgical repair were evaluated by standard two-view (i.e., lateral and ventrodorsal) radiography, tangential view (ventro 20 degrees cranial-dorsocaudal [inlet] and ventro 20 degrees caudal-dorsocranial [outlet]) radiography, and computed tomography (CT). Radiographic and CT examinations were reviewed independently by the three authors, and specific anatomic sites were graded for the presence or possibility of lesions. The results of radiographic interpretations were compared to CT scan interpretations. Eighty-one percent of skeletal lesions detected by CT scans were diagnosed definitively radiographically. Differences between the interpretation of CT and radiographic examinations included abnormalities associated with soft-tissue structures (P < 0.0001), the sacroiliac joints (P = 0.02), and the acetabula (P = 0.04). Interpretation of the lateral/ventrodorsal and inlet/outlet radiographic series were not statistically different, although inlet views may be complimentary to the standard radiographic examination. Its use deserves further study. Reader variation was less on evaluation of CT examinations than radiographic examinations. CT multiplaner reformations and three-dimensional reconstructions were useful for surgical planning in seven dogs. CT scanning is superior to survey radiography in assessing skeletal and soft-tissue injuries in dogs with pelvic trauma, although all clinically significant surgical lesions were described accurately radiographically. Based on this small series, the routine CT examination of dogs with pelvic trauma may not be justifiable for diagnosis but may be advantageous for surgical planning, especially if acetabular fractures are suspected on radiographs.  相似文献   
93.
Renal ultrasonographic findings in 12 dogs and 3 cats determined to have oxalate nephrosis presumed to be secondary to ethylene glycol intoxication were examined. Ultrasonographic changes varied from mild to marked increases in renal cortical echogenicity. A pattern of greater than normal cortical and medullary echogenicity with persistence of areas of lesser echo intensity at the corticomedullary junction and central medullary regions was observed. This pattern, termed the halo sign, was recognized in 7 dogs and 1 cat concurrent with the development of clinical anuria. Ultrasonographic patterns in these clinical cases were similar to those observed in a previous study of dogs with experimentally induced ethylene glycol nephrosis. Ultrasonographic findings were not considered pathognomonic of ethylene glycol nephrosis. Due to the high death rate reported in the cases surveyed, detection of ultrasonographic changes was considered to warrant a guarded to poor prognosis. Because of the association of the halo sign with anuria, its detection was considered to warrant a grave prognosis.  相似文献   
94.
95.
Yearling heifers were given SC injections of 10(8) (n = 40), 10(9) (n = 44), or 10(10) (n = 44) colony-forming units of Brucella abortus strain 19 (S19). The proportion of heifers with positive serologic test results at 1 month following vaccination increased as the dose of S19 increased. These proportions decreased with time, and all heifers had negative card, rivanol, and complement fixation test results within 4 months. Positive ELISA results persisted beyond 4 months in all three S19 dose groups; however, all heifers were ELISA-negative within 9 months after vaccination. Comparable lymphocyte transformation activity was stimulated by S19 dose of 10(9) or 10(10) and approximately half of the heifers in both groups had a positive stimulation index at 9 months. Immunity of the pregnant heifers was challenged 9 months after vaccination with 10(7) B abortus strain 2308 as follows: diluent controls (n = 69); 10(8) B abortus S19 (n = 40); 10(9) B abortus S19 (n = 39); and 10(10) B abortus S19 (n = 39). Tissue specimens from heifers were obtained at parturition and necropsy for culturing of B abortus. The proportion of heifers that developed brucellosis, ie, had positive culture results, increased as gestation days at challenge exposure increased. The effect of gestational age was controlled in the analysis using logistic regression. The relative risk of brucellosis was reduced to 0.38, 0.15, and 0.06 for B abortus S19 doses of 10(8), 10(9), and 10(10), respectively, compared with diluent controls at 1.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
96.
A 2-year-old Thoroughbred gelding was evaluated for a grade 3 out of 5 unilateral hind limb lameness. Flexion of the right hock and stifle joints (spavin test) exacerbated the lameness. Response to intra-articular and perineural anaesthesia isolated the source of lameness to the tarsocrural area, despite an absence of tarsocrural joint effusion. Routine radiographic examination of the hock did not reveal any significant abnormalities. Skeletal nuclear scintigraphic evaluation revealed a focal region of increased bone activity in the proximal medial trochlear ridge of the talus. Flexed lateromedial radiographic views identified three discrete semicircular lytic lesions at the proximal articular margin of the medial trochlear ridge of the talus. Conservative management of the lesions was associated with a successful return to racing. The location and appearance of the osteochondral lesions of this report have not been previously reported and may be a manifestation of developmental orthopaedic disease and abnormal endochondral ossification. Nuclear scintigraphy and flexed lateromedial radiographic views facilitated identification of the lesions. This radiographic view is recommended when lameness is isolated to the tarsocrural joint and standard radio-graphic projections fail to identify a cause.  相似文献   
97.
Nine cats, from 11 to 17 years of age (mean 13.6 years of age), were diagnosed with a cranial mediastinal cyst. Thoracic radiographs in all cats were characterized by an increased soft tissue opacity in the cranial mediastinum confirmed to be a cyst by ultrasonography or necropsy. Ultrasonographically cysts appeared as an anechoic mass. A low-cellularity clear fluid was obtained on aspiration. The majority of the cats (n = 8) presented for unrelated conditions with no signs of respiratory distress. No treatment for the cyst was pursued except for drainage during ultrasonographic-guided aspiration in several cats. On follow-up of eight cats, none were symptomatic for the cyst from 3-45 months after diagnosis. Mediastinal cyst should be considered when a cranial mediastinal mass is evident radiographically in an older cat. The majority of feline cranial mediastinal cysts are benign with no need for treatment.  相似文献   
98.
OBJECTIVE: To determine the clinical characteristics and outcome of foals with septic osteitis of the distal phalanx. DESIGN: Retrospective case series. ANIMALS: 22 foals. PROCEDURES: Information obtained from medical records included signalment; clinical, laboratory, and radiographic findings; treatment method; and outcome. Foals included in the study had lameness referable to the foot, radiographic evidence of localized lysis or focal loss of bone density of the distal phalanx, and suppurative discharge or necrosis of the affected bone evident at surgery. Foals with a history or evidence of penetrating wounds or subsolar abscessation were excluded. RESULTS: Mean age of foals at initial evaluation was 40.8 days (range, 3 to 122 days). Twenty-one (95%) foals had lameness as the primary complaint. Lesions consistent with septic osteitis of the distal phalanx localized to specific areas of the bone on the basis of radiographic and surgical findings were located on the solar margin or toe (14/22 [64%]), extensor process (5/22 [23%]), and palmar or plantar process (3/22 [13%]). Hind limbs (18/26 [69%] affected limbs) were more frequently affected. Two foals had > 1 affected limb, 2 had additional sites of osteomyelitis, and 4 had concurrent septic arthritis. Surgical debridement and regional antimicrobial perfusion were performed during general anesthesia. Extensor process lesions were not debrided. Nineteen of 22 (86%) foals survived to be discharged from hospital, and 16 horses reached racing age. Eleven of 16 had race starts, of which 8 had official race starts and 3 had unofficial race starts. CONCLUSIONS AND CLINICAL RELEVANCE: Septic osteitis of the distal phalanx should be considered as a source of lameness in foals with signs referable to the foot and does not necessarily preclude a career in racing. Although infection may occur secondary to bacterial penetration of the hoof or sole, the distal phalanx should also be considered as a potential site for hematogenous septic arthritis or osteomyelitis in foals.  相似文献   
99.
Summary A knowledge of the biological and functional relationships among traits would be of benefit to plant breeders in the choice of traits to use for increasing efficiency of selection in a breeding program. Principal factor analysis was used to identify biological and functional relationships among dry bean (Phaseolus vulgaris L.) traits in segregating populations of a phenotypic recurrent selection program designed to introduce upright architecture into medium-sized dry bean.Two biological interpretations were assigned to factors extracted in the analysis of four seed/pod traits. The first was a size factor, loaded with seed weight and pod width, and the second a number factor, which was loaded with number of seeds per pod and pod length. Similarly, three factors were extracted from the analysis of fifteen architectural traits. The first factor was interpreted as an elongation factor, and was loaded with internode length measurements, while the second factor was interpreted as a structural factor, and was further divided into two subclasses namely, sturdiness factor and profile factor. The sturdiness factor comprised hypocotyl diameter and hypocotyl length, while the profile factor comprised branch angle and number of basal branches. The third factor which was called a reproductive factor was loaded with pod distribution traits and the number and location of nodes on which pods were borne.  相似文献   
100.
The ion-pair partition properties of mefenamic acid with the methyl, ethyl, n-propyl, and n-butyl homologs of tetraalkylammonium cation were studied in relation to a model of an assay procedure for acidic drugs. Variables studied included identity and concentration of pairing ion and composition of extracting solvents. Resulting data were used to develop a partition chromatographic assay procedure. Standard recoveries averaged 99.01 +/- 0.82%. Assays of commercial capsules were reproducible.  相似文献   
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