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51.
Seasonal variation in the capacity of bank voles, Clethrionomys glareolus (Schreber), to infect larval Ixodes ricinus (L.) ticks with Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt & Brenner was examined from May through October 1991 at Bogesund, near Stockholm in south-central Sweden. Although larval infestations of bank voles were greatest in June and July, nearly 70% of all larval ticks infected with spirochetes by bank voles at this site became infected during August and September. Seasonality of infectivity was related to the degree of earlier nymphal infestation on voles as well as to the age composition of the vole population. These factors may influence the infectivity of other rodent reservoirs of B. burgdorferi, both in Europe and North America. Moreover, in determining the reservoir potential of tick hosts, a host population's spirochetal infectivity should be determined for the entire period of larval infestation rather than just during the period of peak larval infestation. 相似文献
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We recently reported the existence of a new class of aspiny interneurons characterized by their immunoreactivity for the calcium-binding protein calretinin (CR) in human striatum. This group is composed of numerous medium-sized (10-20 microm) neurons with poorly branched dendrites and a smaller number of large-sized (24-42 microm) neurons with highly ramified dendrites. We further demonstrated the selective sparing of the medium-sized, but not all the large-sized, CR+ striatal neurons in Huntington's disease. In the present study, we applied a double-antigen localization method to postmortem striatal tissue obtained from normal individuals to further characterize the chemical phenotype of these two subsets of CR+ neurons. Our results reveal that in the medium-sized neurons, CR is not colocalized with any of the following current markers of striatal neurons: calbindin, parvalbumin, beta-nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d), or choline acetyltransferase (ChAT). Furthermore, quantitative estimates show that the medium-sized CR+ neurons are by far the most abundant type of interneurons in the human striatum. In contrast, CR is colocalized with ChAT in about 80% of the large-sized CR+ neurons. Thus, the medium-sized CR+ neurons appear to form a distinct class of striatal interneurons, whereas most of the large-sized CR+ neurons belong to the population of giant cholinergic neurons. This study has provided the first exhaustive characterization of the chemical phenotype of the CR + neurons in the human striatum. 相似文献
54.
Immunoprecipitation of unactivated avian progesterone receptor results in the copurification of hsp90, hsp70, and three additional proteins, p54, p50, and p23. p23 is also present in immunoaffinity-purified hsp90 complexes along with hsp70 and another protein, p60. Antibody and cDNA probes for p23 were prepared in an effort to elucidate the significance and function of this protein. Antibodies to p23 detect similar levels of p23 in all tissues tested and cross-react with a protein of the same size in mice, rabbits, guinea pigs, humans, and Saccharomyces cerevisiae, indicating that p23 is a conserved protein of broad tissue distribution. These antibodies were used to screen a chicken brain cDNA library, resulting in the isolation of a 468-bp partial cDNA clone encoding a sequence containing four sequences corresponding to peptide fragments isolated from chicken p23. This partial clone was subsequently used to isolate a full-length human cDNA clone. The human cDNA encodes a protein of 160 amino acids that does not show homology to previously identified proteins. The chicken and human cDNAs are 88% identical at the DNA level and 96.3% identical at the protein level. p23 is a highly acidic phosphoprotein with an aspartic acid-rich carboxy-terminal domain. Bacterially overexpressed human p23 was used to raise several monoclonal antibodies to p23. These antibodies specifically immunoprecipitate p23 in complex with hsp90 in all tissues tested and can be used to immunoaffinity isolate progesterone receptor complexes from chicken oviduct cytosol. 相似文献
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AB Santos JC Ballenger JJ Bevilacqua JJ Zealberg TG Hiers S McLeod-Bryant PA Deci LJ Rames 《Canadian Metallurgical Quarterly》1994,151(8):1181-1187
OBJECTIVE: The authors discuss obstacles and incentives associated with successful community-based public-academic liaison activities and illustrate their conclusions by describing their public-academic liaison program, which received the American College of Psychiatrists' first annual Award for Creativity in Psychiatric Education. METHOD: The first 8 years of a state/university collaboration are described in which the parties involved first developed a variety of innovative services designed to fill specific gaps in the public service delivery system and subsequently integrated academic research and training components. RESULTS: The carefully planned and monitored process resulted in the exponential growth of interest in public sector work, the realization of the university's primary goals of developing high quality training and research sites, a substantial increase in the number of graduates accepting positions in the public sector, several projects funded by the National Institute of Mental Health, and two national awards. CONCLUSIONS: These collaborations illustrate the highly complementary relationship of public-academic liaison activities and their potential capacity to improve access to services, substantially improve the quality of these services, generate extramural support for services research, and increase the number of well-trained professionals in the public sector. 相似文献
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The study investigated the effects of the direct and exploration methods of teaching on the overhand throwing performance of kindergarten children. Variable throwing practice was provided in the exploration method by allowing children to throw 5 different types of balls at a variety of targets. Children given the direct method threw only one type of ball and received specific instruction and demonstrations. Throwing for distance and throwing accuracy were measured on pre- and posttests. A novel throwing task was administered on the posttest to measure skill transfer. The experimental groups received instruction three times per week for 4 wk. in throwing while a control group received no instruction. Significant sex differences in throws were found for distance and accuracy. Analysis of data from the novel task gave no significant effects. The two methods of teaching did not produce different levels of throwing skill. 相似文献
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ML Pantelides JV Moore E Forbes TG Truscott NJ Blacklock 《Canadian Metallurgical Quarterly》1993,57(5):838-841
The relative distribution of sensitizer drugs in the prostate and its contiguous organs is of importance in the treatment of localized prostatic cancer with photodynamic therapy. Using the primate model, whose prostate is both morphologically and physiologically homologous with its human counterpart, the distribution of hematoporphyrin derivative (HpD) amongst organs of urological interest was determined. Hematoporphyrin derivative levels were comparatively low in both caudal and cranial prostatic lobes (0.93-1.77 micrograms/g) and were similar to those in rectum, urethra and the skin. The reticuloendothelial organs, liver, spleen and also the kidney accumulated the highest quantities of porphyrin (4.76-9.8 micrograms/g, liver > spleen > kidney). Despite a high avidity of prostatic tissue for zinc, a zinc-metalloporphyrin (Zn-HpD) did not concentrate selectively in the prostate. The results are of clinical value in view of the homology between the primate and the human. 相似文献
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TG Wadsworth 《Canadian Metallurgical Quarterly》1976,(119):197-201
For 10 years prior to the availability of the Olecranon Screw described in this article, oblique fixation using a regular Sherman bone screw was employed for displaced fractures (with a suitable fragment) by engaging the anterior ulnar cortex. Internal fixation was supplemented by a split for 3 weeks. The reason for a special olecranon screw is to eliminate the necessity for additional fixation and permit early motion. No instance of non-union or important restriction of motion or serious complication has been encountered. 相似文献