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321.
Field experiments were conducted to determine the non-target impact of foliar-applied diquat on selected plant species. Diquat was applied to emerged bracken fern, chain fern, slash pine, soybean, sunflower, cotton, corn, and onion at rates varying from 0.02–4.5 kg ai ha−1 of diquat cation, which allowed for the determination of the no-effect rate and the rate that caused 25, 50, and 100% injury, as measured by visual injury ratings, plant heights, and dry weights. Bracken fern, chain fern, and slash pine were more tolerant to diquat and exhibited regrowth potential at the higher rates. The other six species were not only more susceptible to diquat, but they did not exhibit regrowth potential at high rates. However, these species were able to recover from slight injury caused by the lower rates of diquat.  相似文献   
322.
The medical records of 11 cats with full‐thickness intestinal biopsies and histopathologic confirmation of segmental mucosal fibrosis were reviewed. All cats received an abdominal ultrasonographic evaluation. The sonographic feature of a small intestinal mucosal hyperechoic band paralleling the submucosa was present in all cats. Other intestinal sonographic findings included wall thickening, and altered wall layering (increased mucosal echogenicity, thickened submucosa, and/or muscularis layer). None of the cats had complete loss of wall stratification. All cats had clinical signs related to the gastrointestinal (GI) tract at the time of presentation. Three of the 11 cats had palpably thickened small intestinal loops, 3/11 abdominal pain, and 2/11 abdominal fluid. Histopathologically, mucosal fibrosis was associated with inflammatory cell infiltrates in all cats. In those cats with histopathologic evidence of mural fibrosis, all cats had a visible hyperechoic band through several intestinal segments. We speculate that the hyperechoic mucosal band represents the zone of mucosal fibrosis. Independently and prospectively, we reviewed the clinical presentation of 35 cats having this visible hyperechoic mucosal band on ultrasound. Twenty‐four of these 35 cats had clinical signs related to the digestive system at the time of record. Our study suggests that the hyperechoic mucosal band represents fibrosis, and in presence of concurrent GI signs, further diagnostic tests may be warranted.  相似文献   
323.
Objective— To adapt the multiple osteochondral autograft technique for treatment of a subchondral cystic lesion (SCL) of the proximal medial trochlear ridge (MTR) of the equine talus and assess long term outcome.
Study Design— Case report.
Animals— Quarter horse stallion with SCL of the proximal MTR of the talus.
Methods— Osteochondral autograft techniques used in dogs and humans were adapted and optimized in equine cadavers. A horse with a SCL of the MTR of the talus was treated by osteochondral autografting. Three osteochondral autografts were harvested from the distal lateral trochlear ridge of the talus in the affected tarsus. No curettage or debridement of the osteochondral lesion was performed. Three recipient beds were predrilled and osteochondral autografts were press-fit into the proximal MTR of the talus. Outcome was assessed by radiography, telephone interview of the owner, and direct observation during training.
Results— Postoperative radiographs indicated excellent filling of the osteochondral defect and graft-articular surface congruency. No complications were encountered after surgery. At 10 months after surgery, the horse successfully re-entered reining training, and continued to be sound and performing athletically 2 years after surgery.
Conclusion— Osteochondral autografting deserves consideration and further evaluation as a primary treatment option for SCL of the proximal MTR of the talus in horses.
Clinical Relevance— Based on the outcome of this case, osteochondral autografting appears to be a safe, valuable and realistic option for treating SCL of the proximal MTR of the talus in equine athletes.  相似文献   
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EXPERIMENTAL STUDIES OF THE MORTALITY AND PLASTICITY OF A WEED   总被引:1,自引:0,他引:1  
Summary. An attempt is made to show the ways in which a population of annual plants may react to increasing density so that the population becomes self-regulatory. The reactions of Agrostemma githago to increasing density lake the form of increasing mortality and plastic response in the size and reproductive capacity of individuals. Experiments are described in which both of these reactions occur and it is shown that interference between Agrostemma and other species may influence either or both reactions. The significance of these observations for understanding the mechanism of natural selection is stressed.
Etude expérimentale de la mortalité et de la plasticité d'une mauvaise herbe  相似文献   
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A five-year-old female English Springer Spaniel was evaluated for chronic episodic anaemia, pigmenturia and icterus. There was increased erythrocyte pyruvate kinase activity, increased in vitro erythrocyte alkaline fragility, decreased erythrocyte 2,3-diphosphoglycerate activity and severely decreased erythrocyte phosphofructokinase activity. The clinical features and haematological values were identical with erythrocyte phosphofructokinase deficiency and resulting nonspherocytic haemolytic anaemia recently described in this breed.  相似文献   
328.
Positive cultures were obtained from 60 equine orthopedic cases during a 12 year period (1974-1985). These cases consisted of 34 long or cuboidal bone fractures, 13 arthrotomy/arthroscopy procedures for removal or internal fixation of a fracture, 7 proximal splint bone fractures, and 6 facial or mandibular fractures. Excluding the 13 arthrotomies, only 10 (21%) of the 47 were open fractures. Multiple organisms were isolated from 36 cases (20 long or cuboidal bone fractures, 7 splint bone fractures, 5 mandibular fractures, and 4 intra-articular fractures). Of the 142 isolates, 35 (24%) were members of the family Enterobacteriaceae, 33 (23%) Streptococcus spp., and 25 (18%) Staphylococcus spp. with the majority being coagulase positive (65%). Other organisms isolated were Pseudomonas spp. (16, 11%), obligate anaerobes (11, 7%), and Actinobacillus spp. (7, 5%). the remaining 10% consisted of Pasteurella spp., Bacillus spp., Corynebacterium spp., Micrococcus spp., and Actinomyces spp. When comparing results between two time periods (1974-1979 and 1980-1985) there was an increase in the percentage of coagulase positive staphylococci isolates resistant to all antimicrobics tested except oxacillin and amikacin, and Escherichia coli isolates were resistant to all but amikacin. For Pseudomonas spp., resistance to gentamicin increased in the second time period (1980-1986). During the initial time period (1974-1979) culture tests for obligate anerobes were not conducted until 1975. No anerobes were cultured during those initial 5 years; however, one third of those isolated after 1980 were resistant to penicillin and ampicillin.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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330.
Objective- The purpose of this study was to determine the results of a new technique for management of prostatic retention cysts in dogs.
Study Design- A retrospective clinical study.
Animals- Eighteen client-owned dogs.
Methods- Dogs with prostatic retention cysts were treated by celiotomy and drainage of the cysts. The majority of the cyst wall was resected and residual cyst cavities were packed with omentum. All dogs were castrated.
Results- Long-term resolution of clinical signs was achieved in all dogs, with follow-up periods ranging from 6 to 42 months. Five dogs developed urinary incontinence postoperatively. This persisted in two dogs, but was well controlled with phenylpropanolamine. In the remaining dogs, the incontinence was transient and resolved within 2 months of surgery.
Conclusions- Partial cyst resection combined with omentalization and castration was a simple and effective means of managing prostatic retention cysts. The incidence of serious complications, including postoperative urinary incontinence, was low.  相似文献   
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