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1.
A novel technique was developed to estimate the caudal medial tibial plateau landmark in the face of osteophytosis to improve accuracy in tibial plateau angle measurements. Using this technique, tibial plateau angles were evaluated in 31 normal dogs before and 8 months after right cranial cruciate ligament transection. There was no significant difference in mean tibial plateau angle before or after induction of osteophytosis. Additionally, it was determined that 90% of dogs had a difference of =2 degrees between right and left tibial plateau angles, which was considered symmetrical.  相似文献   
2.
Selected information was compiled from canine urinalyses and urine cultures conducted between January 1969 and December 1995. Eight thousand three hundred fifty-four microbial isolates (bacteria and fungi) included 4,873 isolates from females and 3,481 from males. Ten bacterial genera accounted for 96.3% of the urinary isolates, including Escherichia coli (44.1%), Staphylococcus spp. (11.6%), Proteus spp. (9.3%), Klebsiella spp. (9.1%), Enterococcus spp. (8.0%), and Streptococcus spp. (5.4%) as the 6 most common isolates in both genders of dogs. Among these 6 genera, female dogs were generally predisposed over males, although males had more urinary tract infections (UTIs) caused by Klebsiella spp. Distributions of ages at UTI diagnosis tended to be similar between genders. Infection with a single microbial species was responsible for >72% of UTIs in both genders. Among females, 40 breeds and a mixed-breed group represented 90.2% of all positive urine cultures, 88.4% of the individual dogs with UTIs. and 88.2% of the microbial isolations. Among males, these same 41 breed groups represented 87.9% of all positive urine cultures, 87.6% of the individual dogs, and 88.2% of the microbial isolations.  相似文献   
3.
Laboratory records of bacterial urine cultures from 383 dogs with recurrent or persistent urinary tract infections (UTI) diagnosed at the University of California Veterinary Medical Teaching Hospital (VMTH) between 1969 and 1995 were reviewed retrospectively to characterize the bacteria involved and their association with age, gender, and breed of dogs affected. Sixty-eight breeds and a mixed-breed group were represented. Escherichia coli was the most common isolate, although mixed-bacterial infections were seen in 58% of the female and 55% of the male dogs. Recurrent and persistent UTI were most prevalent in middle-aged to older German shepherd dogs, miniature/toy poodles, and Labrador retrievers, with no apparent sex predilection. Criteria fitting recurrent and persistent UTI were present in 0.3% of all dogs seen at the VMTH during this 26-year period.  相似文献   
4.
This article contains an analysis of data compiled from 813 specimens of canine uroliths submitted to the Urinary Stone Analysis Laboratory at University of California School of Veterinary Medicine.  相似文献   
5.
Traditional forms of farming, herding, and fishing are remarkably adapted to African conditions but these traditional approaches are being overtaken by modern pressures, particularly population growth. According to a report published by the Office of Technology Assessment (OTA), a nonpartisan analytical support agency of the U. S. Congress, one promising way to help African farmers and herders would be for development assistance organizations to focus more attention on the various forms of low-resource agriculture that predominate in Africa. In keeping with OTA's mission and primary audience, “Enhancing Agriculture in Africa: A Role for U. S. Development Assistance” (1988) is a policy-oriented synthesis of available technical information. The report provides Congress with a range of options that, if pursued, could help Africans enhance agriculture, increase their food security, and improve their lives. This paper is drawn from the larger OTA report, and it focuses on the role technology might play in enhancing low-resource agriculture. Readers should see the full assessment (OTA, 1988) for more information on policy considerations; the specific technologies mentioned; or a complete list of advisory panel members, workshops and participants, and commissioned papers. OTA's report comes at a critical time: for a variety of reasons—ranging from changing values to increased budget constraints—U. S. foreign assistance policy is undergoing a fundamental reevaluation. This review of the potential of low-resource agriculture, and options the United States might pursue to enhance this approach, was intended to aid in this reevaluation.  相似文献   
6.
Directed chemical synthesis can produce a vast range of molecular structures, but the intended product must be known at the outset. In contrast, evolution in nature can lead to efficient receptors and catalysts whose structures defy prediction. To access such unpredictable structures, we prepared dynamic combinatorial libraries in which reversibly binding building blocks assemble around a receptor target. We selected for an acetylcholine receptor by adding the neurotransmitter to solutions of dipeptide hydrazones [proline-phenylalanine or proline-(cyclohexyl)alanine], which reversibly combine through hydrazone linkages. At thermodynamic equilibrium, the dominant receptor structure was an elaborate [2]-catenane consisting of two interlocked macrocyclic trimers. This complex receptor with a 100 nM affinity for acetylcholine could be isolated on a preparative scale in 67% yield.  相似文献   
7.
The most abundant water soluble natural food colors are betacyanins and anthocyanins. Similarly, lycopene, bixin, beta-carotene, and chlorophyll are water insoluble colors. Pure betanin, bixin, lycopene, chlorophyll, beta-carotene, and cyanidin-3-O-glucoside were isolated from Beta vulgaris, Bixa orellana,Lycopersicum esculentum, Spinacia oleracea, Daucus carrota, and Prunus cerasus, respectively. These natural pigments, alone and in combination, were evaluated for their relative potencies against cyclooxygenase enzymes and tumor cell growth inhibition by using MCF-7 (breast), HCT-116 (colon), AGS (stomach), CNS (central nervous system), and NCI-H460 (lung) tumor cell lines. Among the colors tested, betanin, cyanidin-3-O-glucoside, lycopene, and beta-carotene inhibited lipid peroxidation. However, all pigments tested gave COX-1 and COX-2 inhibition and showed a dose-dependent growth inhibition against breast, colon, stomach, central nervous system, and lung tumor cells, respectively. The mixtures of these pigments were also evaluated for their synergistic effects and chemical interactions at various concentrations. The mixture of anthocyanin and betanin negated their efficacy in the cell growth inhibitory assay and did not enhance the COX enzyme inhibitory activity. This is the first report of a comparative evaluation and the impact on biological activities of these pigments alone and in combination.  相似文献   
8.
In vitro susceptibility testing correctly predicted the outcome of ampicillin therapy in all 56 urinary tract infections (UTI) caused by coagulase-positive staphylococci (Staphylococcus aureus and S intermedius), in all 26 UTI caused by Proteus mirabilis, in 38 of 44 UTI caused by Escherichia coli, in 29 of 31 UTI caused by Streptococcus spp, in 8 of 10 UTI caused by Klebsiella pneumoniae, and in 16 of 20 UTI caused by other bacterial species. Thus, 173 of 187 (92.5%) isolates responded to ampicillin therapy in a manner predicted by in vitro susceptibility test results. In vitro susceptibility testing correctly predicted the outcome of therapy with trimethoprim-sulfa in 119 of 138 UTI caused by Escherichia coli, in 33 of 45 UTI caused by Klebsiella pneumoniae, in 38 of 43 UTI caused by Proteus mirabilis, in 21 of 25 UTI caused by Streptococcus spp, in 9 of 11 UTI caused by coagulase-positive staphylococci, and in 19 of 21 UTI caused by other bacterial species. Thus, 239 of 283 (84%) isolates responded to trimethoprim-sulfa therapy in a manner predicted by in vitro susceptibility test results.  相似文献   
9.
Fluoroscopically assisted percutaneous nephropyelocentesis and/or antegrade ureterography was performed on six dogs. These technics were useful for obtaining renal pelvic urine specimens for culture. Percutaneous nephropyelocentesis confirmed diagnoses of pyelonephritis. Injection of a radiopaque contrast medium into the ureter or renal pelvis was useful in evaluating the ureter in those dogs in which excretory urography provided insufficient detail. No complication was associated with the technics.  相似文献   
10.
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