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101.
102.
Castillo D Paredes C Zañartu C Castillo G Mercado R Muñoz V Schenone H 《Boletín chileno de parasitología》2000,55(3-4):86-91
Most of cases of visceral larva migrans syndrome are caused by Toxocara canis larvae. Man acquires the infection by accidental ingestion of ripe eggs of the helminth. In order to find out the frequency of the presence of Toxocara sp. eggs in dog fecal specimens from public places of Santiago city in 1999 july-september a study was carried out in 84 squares and 12 parks from 32 counties. Three fecal samples were collected in each of these places, making a total of 288. Each sample was processed according to a modified Telemann method and three smears of each were microscopically examined. Toxocara sp. eggs were found in 39 (13.5%) fecal specimens. In 28/84 (33.3%) squares and in 8/12 (66.7%) parks these eggs were detected. These results make necessary the control of dogs and cats populations with the aim of reduce the presence of animals without responsible owners. It should be advisable to prevent dogs and cats defecation in public areas grounds, trying to exclude these animals from recreation areas. 相似文献
103.
Carmelo E Pérez JA Zurita AI Piñero J de Armas F del Castillo A Valladares B 《The Journal of parasitology》2000,86(4):844-846
In this paper, we report a method for isolation of high molecular weight DNA from Leishmania promastigotes. This technique is especially indicated for small-scale purification of DNA suitable for the construction of highly representative genomic libraries. In our protocol, lysis buffer is compatible with RNase treatment, avoiding an additional precipitation step and consequent shearing of DNA. In order to prove the quality of the DNA isolated by this method, a Leishmania braziliensis genomic library was constructed, and an L. braziliensis KMP-11 gene was cloned after screening the library with a heterologous probe. 相似文献
104.
Seven Hox cluster-related genes (Dthox-A to -G) have been isolated from the freshwater triclad Dugesia (G.) tigrina, their
sequence compared to other Hox genes and their expression in intact and regenerating organisms analyzed by whole mount in
situ hybridization. Sequence comparison analyses show high similarities of D. tigrina Hox genes to anterior and medial groups
of coelomate Hox genes. Expression analyses show very early, synchronous, and overlapping expression of Dthox -A, -E, -G and
-F in anterior, posterior and lateral regenerative tissues. At one hour of regeneration all Dthox genes studied showed a neat,
clear expression at the wound boundary. Later, as the blastema grows, the expression area expands to more proximal regions
covering the blastema and the distal postblastema regions. Blastemas formed by intercalary regeneration also show a synchronous
expression of the same Hox genes though the onset of activation is much delayed. The finding that the same set of Hox genes
is synchronously activated in anterior, posterior, intercalary and lateral regeneration is in sharp contrast to its well established
role in specifying antero-posterior pattern during embryonic development. The implications of these results as regards ancestral
versus co-opted roles of Hox genes in development and regeneration are discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
105.
Thirty-two barley cultivars grown in Spain, 18 of the two-row type and 14 of the six-row type, were screened for plant regeneration
from cultured immature embryos. Although there was much variation in regeneration capacity among the cultivars, plants were
obtained from all cultivars except Almunia. No statistical differences were found in the percentage of regeneration between
two- and six-row types. The influence of the auxins 2,4-dichlorophenoxyacetic acid, dicamba, and picloram on the induction
and maintenance of embryogenesis and regeneration capacity after 3–4 months in culture, were evaluated for cultivars Cobra,
Hop and Reinette. Hop had the highest rates of maintenance of embryogenic capacity and plant regeneration. The medium containing
dicamba gave the best embryogenic callus induction, maintenance and regeneration. Five regeneration media, differing in growth
regulators and micronutrient composition, as well as partial desiccation of the calli before regeneration, were tested. The
regeneration medium containing 10 μm copper sulfate gave the best results. Regeneration frequencies after 3–4 months in culture of cultivar Hop were raised from
59.5 to 93.7% in this medium. Silver nitrate and partial desiccation of the calli also enhanced plant regeneration, but the
medium containing 10 μm of silver nitrate reduced root formation.
Received: 30 October 1997 / Revision received: 3 April 1998 / Accepted: 17 April 1998 相似文献
106.
Petit H Nègre-Sadargues G Castillo R Valin S Trilles JP 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》1998,119(2):523-527
Penaeus japonicus postlarvae, reared under laboratory conditions, were fed an astaxanthin enriched diet to the investigate carotenoid metabolic capabilities during the postlarval development. Animals fed astaxanthin were found to absorb this carotenoid. The decrease of pigment concentration in the carotenoid starved group is related to the duration of the experimental feeding conditions; the carotenoid depletion depends upon the postlarval status at the starting point. As has been shown for adult prawns, the carotenoid pattern of postlarval stages, regardless of the diet, consists mainly of free and esterified astaxanthin; the relative amounts of these fractions undergo slight variations depending on the diet. 相似文献
107.
José C. Aponte Abraham J. Vaisberg Denis Castillo German Gonzalez Yannick Estevez Jorge Arevalo Miguel Quiliano Mirko Zimic Manuela Verástegui Edith Málaga Robert H. Gilman Juan M. Bustamante Rick L. Tarleton Yuehong Wang Scott G. Franzblau Guido F. Pauli Michel Sauvain Gerald B. Hammond 《Bioorganic & medicinal chemistry》2010,18(8):2880-2886
The synthesis of 2-(5,6,7,8-tetrahydro[1]benzothieno[2,3-d]pyrimidin-4-yl)hydrazone-derivatives (BTPs) and their in vitro evaluation against Trypanosoma cruzi trypomastigotes, Mycobacterium tuberculosis, Leishmania amazonensis axenic amastigotes, and six human cancer cell lines is described. The in vivo activity of the most active and least toxic compounds against T. cruzi and L. amazonensis was also studied. BTPs constitute a new family of drug leads with potential activity against infectious diseases. Due to their drug-like properties, this series of compounds can potentially serve as templates for future drug-optimization and drug-development efforts for use as therapeutic agents in developing countries. 相似文献
108.
Kristina Cockle Gabriel Capuzzi Alejandro Bodrati Rob Clay Hugo del Castillo Myriam Velázquez Juan I. Areta Nestor Fariña Rodrigo Fariña 《Journal of Field Ornithology》2007,78(1):21-39
ABSTRACT. Vinaceous Amazons ( Amazona vinacea ) are endemic to the Atlantic forest of southeastern Brazil, eastern Paraguay, and the province of Misiones in Argentina. We searched for Vinaceous Amazons throughout the western part of its range in Argentina and Paraguay during 1639 days of fieldwork from 1997 to 2006. These parrots have disappeared from most areas where they were historically recorded in these countries, and are now limited to a few sites in northeastern Paraguay and central Misiones (Argentina). We estimate the minimum remaining populations at 220 individuals in Paraguay and 203 individuals in Argentina. Important sites for the species are (1) the farming area from San Pedro to Tobuna (Misiones, Argentina) and (2) the Itaipú reserves complex and Reserva Natural Privada Itabó (Paraguay). In our surveys, Vinaceous Amazons were absent from the largest tracts of forest in Misiones, and were most often observed feeding, roosting, and nesting in small forest remnants and in agricultural areas that included forest fragments and isolated trees. Threats to amazons in these areas include nest poaching, forest clearing, and being shot as a crop pest. We confirmed 40 Vinaceous Amazons kept as pets in 35 homes between San Pedro and Tobuna. Environmental education and law enforcement are urgently needed to reduce threats in populated areas, and subsistence farmers need technical and logistical support to slow or stop the conversion of forest into cropland. Finally, additional study is needed to determine this amazon's habitat preferences, nest site requirements, and demography in different habitats. 相似文献
109.
Sara Garcia‐Serrano Carolina Gutiérrez‐Repiso Montserrat Gonzalo Juan Garcia‐Arnes Sergio Valdes Federico Soriguer Vidal Perez‐Valero Miguel A. Alaminos‐Castillo Juan Francisco Cobos‐Bravo Francisco J. Moreno‐Ruiz Alberto Rodriguez‐Cañete Francisca Rodríguez‐Pacheco Eva Garcia‐Escobar Eduardo García‐Fuentes 《Obesity (Silver Spring, Md.)》2015,23(8):1607-1615
110.