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排序方式: 共有277条查询结果,搜索用时 15 毫秒
1.
Two hundred eighteen usable serum samples were collected from hunter-killed collared peccaries (Tayassu tajacu) during March 1986, in three areas of Arizona. Evaluations for antibodies against vesicular stomatitis virus (VSV) New Jersey (NJ) type, VSV Indiana type, pseudorabies virus, brucellosis, and leptospirosis revealed positive test results in 8%, 0%, less than 1%, 0%, and 23% of the sera, respectively. Exposure of peccaries to VSV (NJ) was widespread, but variation in the prevalence of seropositive peccaries was not found between the three areas sampled. The exposure of peccaries to VSV (NJ) probably was related to the recent epizootics in livestock in the vicinity. Exposure to Leptospira interrogans serovars also was widespread, and geographic variation in the prevalence of peccaries with antibodies against L. interrogans was found. 相似文献
2.
The results of surveillance for hog cholera (HC) in wild swine (Sus scrofa) collected from throughout the United States from 1979 to 1987 are presented. Sera collected from 1,218 wild swine and tissues from 637 were evaluated for HC antibodies and virus, respectively. Included within this surveillance were samples from Santa Cruz and Santa Rosa Islands, California, where HC virus had been deliberately introduced into wild swine during the 1950's in attempts to eradicate these animals. All evaluations were considered negative for HC. It appears that the HC virus does not maintain itself in dispersed swine populations and that wild swine have not remained a reservoir of HC since its eradication in domestic swine in the United States. 相似文献
3.
Gender, age and circadian blood pressure variation of apparently healthy rural vs metropolitan Japanese 总被引:1,自引:0,他引:1
K Otsuka H Watanabe G Cornélissen M Shinoda K Uezono T Kawasaki F Halberg 《Chronobiologia》1990,17(4):253-265
Interim chronobiologic cardiovascular reference data have been described; 353 clinically healthy Japanese subjects were monitored every 15 min for 24h on 2 occasions. Special attention was paid to the difference between metropolitan and rural areas. Not only the MESORs of SBP and DBP, but also the circadian amplitudes, were higher in the Tokyo than in a rural area (Komaki, Aichi Prefecture). Age-related alterations in the circadian profile of cardiovascular variables were noted for women but not for men. The average MESOR remained similar for SBP in men, whereas in women the average MESOR increased with advancing age in both urban and rural areas. The average circadian amplitude of SBP also increased with age in women, but not in men. No significant deviations of acrophase with age were found for SBP and DBP in men, whereas in rural women the acrophase tended to occur earlier with increasing age. 相似文献
4.
Age, gender and circadian or circasemidian blood pressure and heart rate variation of children. 总被引:1,自引:0,他引:1
Systolic (S) and diastolic (D) blood pressure (BP) and heart rate (HR) of clinically healthy children (24 boys and 15 girls) 3 to 7 years of age were measured with a standard mercury sphygmomanometer at 3-hour intervals for 24 hours in April 1991. The children slept and/or rested from 2100 to 0700 and napped from 1230 to 1530; they had meals at 0730, 1200 and 1800. A statistically significant circadian and about 12-hour (circasemidian) component of variation is documented for SBP and DBP of boys and girls and for HR of boys. No gender difference was found for the circadian and circasemidian components. A positive correlation with age is found for the MESOR and circadian amplitude of SBP and DBP (p < 0.05); a negative correlation with age is found for the MESOR of HR (p < 0.001). 相似文献
5.
F Cornélis L Hashimoto J Loveridge A MacCarthy V Buckle C Julier J Bell 《Genomics》1992,13(3):820-825
The creation of a comprehensive genetic map in human has been limited by the lack of highly polymorphic markers spaced evenly throughout the human genome. We have utilized yeast artificial chromosomes (YAC) containing large human DNA inserts to help identify highly polymorphic (CA)n repeats at a chosen locus. The DNA of a YAC containing the locus was subcloned in M13 vectors, and the recombinants were screened at high stringency to detect preferentially long (CA)n repeats (n greater than 20). These repeats, which are the most likely to be highly polymorphic, were then studied to confirm both the level of polymorphism and their precise genetic location. This strategy has permitted the identification of a new, highly polymorphic CA repeat (77% heterozygosity) at the T cell receptor alpha chain (TCRA) locus on chromosome 14q. It provides a powerful marker for assessing the role of this locus in the susceptibility to autoimmune and infectious diseases. This approach should permit the development of highly polymorphic markers at any targeted locus and rapidly improve the current human genetic map. 相似文献
6.
Corné M. J. Pieterse Anne-Marie C. E. Derksen Jindra Folders Francine Govers 《Molecular & general genetics : MGG》1994,244(3):269-277
The ipiB and ipiO genes of the potato late blight fungus Phytophthora infestans (Mont.) de Bary were isolated from a genomic library in a screen for genes induced in planta. Expression of these genes was studied during pathogenesis on various host tissues and different host plants, some of which show specific resistance against P. infestans infection. During pathogenesis on leaves and tubers of the fully susceptible potato cultivar (cv.) Ajax and on leaves of the fully susceptible tomato cv. Moneymaker, the P. infestans ipiB and ipiO genes show a transient expression pattern with highest mRNA levels in the early stages of infection. During the interaction with leaves of the partially resistant potato cv. Pimpernel, the expression is also transient but accumulation and disappearance of the mRNAs is delayed. Also in P. infestans inoculated onto a race-specific resistant potato cultivar and onto the nonhost Solanum nigrum, ipiB and ipiO mRNA is detectable during the initial stages of infection. Apparently, the expression of the ipiB and the ipiO genes is activated in compatible, incompatible and nonhost interactions. In encysted zoospores, ipiB and ipiO mRNA accumulation was not detectable, but during cyst germination and appressorium formation on an artificial surface the genes are highly expressed. Expression studies in mycelium grown in vitro revealed that during nutrient starvation the expression of the ipiB and ipiO genes is induced. For ipiO gene expression, carbon deprivation appeared to be sufficient. The ipiO gene promoters contain a sequence motif that functions as a glucose repression element in yeast and this motif might be involved in the regulation of ipiO gene expression. 相似文献
7.
Hüiwan Han Dali Shao Jinyi Wu Germaine Cornélissen Franz Halberg 《Cell biochemistry and biophysics》1991,18(3):217-229
An earlier demonstration of a circadian rhythm in rat atria by others is complemented herein by observations in culture: A single murine myocardial cell and two sets of grouped cells beating in culture for several days reveal several features of an anticipated, presumably built-in spectrum of multifrequency rhythms and trends, the chronome. Circadian and about 12-h (circasemidian) components are modulated by an approximately 84-h (circasemiseptan) component, which cannot be separated from trends in view of the brevity of the series. The circumstance under which the culture is aging and in which fibroblasts proliferate is a further complication that limits the findings to a single cycle reproduced in three separate cultures. Whether it is a rhythm that repeats itself or a response to placement into culture, an approximately 3.5-d component in the beating of myocardial cells in culture is to be aligned with a very prominent similar component found in the incidence of 85,819 human myocardial infarctions. 相似文献
8.
A crocodilian skeleton from the «série du gypse d'Aix (basal Aquitanian) at Venelles (Bouches-du-Rhône) is described and referred to Diplocynodon cf. rateli. The specimen seems to have been mutilated by scavengers before burial. The occurrence of the freshwater crocodilian Diplocynodon in the «série du gypse d'Aix is in agreement with recent reconstructions of the depositional environment, which suggest a basin with a fluctuating, but usually low, salinity. 相似文献
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