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Sensory evaluation indicated that aspartylphenylalanine methyl ester is about 160 times sweeter than sucrose in aqueous solution. Blends of this dipeptide with (i) sodium saccharin, (ii) sodium saccharin and sucrose, and (iii) sodium saccharin, sucrose, and calcium cyclamate did not differ significantly from 4 or 12 percent sucrose in bitterness, off-flavors, or aftertaste.  相似文献   
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Soft tissue calcification in guinea pigs has been attributed to a mineral imbalance, especially a relative or absolute magnesium deficiency. An associated chronic tubular nephritis has been reported and was substantiated in the present study.

The location of the parathyroid glands of guinea pigs was established, and their size estimated by microscopic methods. The size and morphologic characteristics of parathyroids of guinea pigs affected with metastatic calcification were indistinguishable from parathyroids of healthy guinea pigs.

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OBJECTIVE: To determine proportions of cats in which feline infectious peritonitis (FIP) was diagnosed on an annual, monthly, and regional basis and identify unique characteristics of cats with FIP. DESIGN: Case-control study. SAMPLE POPULATION: Records of all feline accessions to veterinary medical teaching hospitals (VMTH) recorded in the Veterinary Medical Data Base between January 1986 and December 1995 and of all feline accessions for necropsy or histologic examination at 4 veterinary diagnostic laboratories. PROCEDURE: Proportions of total and new feline accessions for which a diagnosis of FIP was recorded were calculated. To identify characteristics of cats with FIP, cats with FIP were compared with the next cat examined at the same institution (control cats). RESULTS: Approximately 1 of every 200 new feline and 1 of every 300 total feline accessions at VMTH in North America and approximately 1 of every 100 accessions at the diagnostic laboratories represented cats with FIP. Cats with FIP were significantly more likely to be young, purebred, and sexually intact males and significantly less likely to be spayed females and discharged alive than were control cats. The proportion of new accessions for which a diagnosis of FIP was recorded did not vary significantly among years, months, or regions of the country. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that FIP continues to be a clinically important disease in North America and that sexually intact male cats may be at increased risk, and spayed females at reduced risk, for FIP. The high prevalence of FIP and lack of effective treatment emphasizes the importance of preventive programs, especially in catteries.  相似文献   
105.
A multiplex Polymerase Chain Reaction (PCR) assay was developed to detect and quantify four fungal foliar pathogens in wheat. For Septoria tritici (leaf blotch) and Stagonospora nodorum (leaf and glume blotch), the -tubulin gene was used as the target region. Diagnostic targets for Puccinia striiformis (stripe or yellow rust) and P. recondita (brown rust) were obtained from PCR products amplified with -tubulin primer sequences. Final primer sets were designed and selected after being tested against several fungi, and against DNA of infected and healthy wheat leaves. For detection of the four pathogens, PCR products of different sizes were amplified simultaneously, whereas no products were generated from wheat DNA or other non-target fungi tested. The presence of each of the diseases was wheat tissue- and cultivar specific. Using real-time PCR measurements with the fluorescent dye SYBR Green I, PCR-amplified products could be quantified individually, by reference to a standard curve generated by adding known amounts of target DNA. Infection levels for each of the diseases were measured in the flag leaf of 19 cultivars at Growth Stage (GS) 60–64 in both 1998 and 1999. The infection levels for the cultivars were ranked, and showed, with a few exceptions, a good correlation with the NIAB Recommended List for winter wheat, which is based on visual assessment of symptoms. With PCR, the presence of the different pathogens was accurately diagnosed and quantification of pre-symptomatic infection levels was possible. Although sampling and DNA detection methods need further optimisation, the results show that multiplex PCR and quantitative real-time PCR assays can be used in resistance screening to measure the interaction between different pathogens and their hosts at different growth stages, and in specific tissues. This should enable an earlier identification of specific resistance mechanisms in both early-stage breeding material and field trials.  相似文献   
106.
A retrospective review of case records of ultrasonography and necropsy outcomes of 62 koalas was used to investigate the accuracy of ultrasonography in assessing koala urogenital tract structural disease at the Port Macquarie Koala Hospital. The results showed high concordance, supporting ultrasonography as an effective tool for evaluating structural disease of the koala urogenital tract, most commonly seen with chlamydiosis. The study also illustrates the advances benefiting animal welfare that can be made by wildlife carer groups through using a scientific, evidence‐based approach.  相似文献   
107.
The impact of Ranger VIII gives us the first chance to test the crater-forming process on the moon and to ascertain the existence of gravity scaling.  相似文献   
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