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101.
We screened 44 heterologous microsatellites isolated in species of the families Threskiornithidae, Ciconiidae and Ardeidae for their use in a migratory waterbird, the white-faced ibis Plegadis chihi (Vieillot, 1817) (Threskiornithidae). Of the screened loci, 57% amplified successfully and 24% were polymorphic. In two breeding colonies from southern Brazil (N = 131) we detected 32 alleles (2-10 alleles/locus). Average He over all loci and colonies was 0.55, and the combined probability of excluding false parents, 98%. There was no departure from HWE in any loci or population. Eru6 and Eru4 loci were in non-random association in the Alvorada colony, and NnNF5 and Eru5 in both populations. AMOVA analysis indicated that most of the genetic diversity was contained within populations. Structure analysis suggested a single population, and F(ST) value showed weak genetic structuring (F(ST) = 0.009, p = 0.05). The two populations are apparently connected through gene-flow. The panel of six microsatellites optimized here was sufficiently informative for characterizing the genetic diversity and structure in these natural populations of the white-faced ibis. The information generated could be useful in future studies of genetic diversity, relatedness and the mating system in Plegadis chihi and related species.  相似文献   
102.
Seasonal migration and the dispersal of juvenile and adult Wood Storks (Mycteria americana) after breeding have been documented in the United States, but little is known about the post‐breeding movements of Wood Storks in South America. Our objective was to identify the locations of post‐breeding areas used by Wood Storks banded as nestlings in breeding colonies in Brazil by analyzing banding data. During the period from 1984 to 2007, 2543 nestlings were banded at breeding colonies in three regions of Brazil, with most (94%) banded in the Pantanal wetland in west‐central Brazil. Seventeen bands were subsequently recovered, with most (14) recovered in southern Brazil and northern Argentina. The mean distance between banding and recovery sites was 1265 km. Our results suggest that Wood Stork movements from breeding areas in Brazil are, as also reported in the United States, in response to changing water levels. The rainy season begins at the end of the breeding season and, in apparent response to rising water levels, Wood Storks in our study moved to drier areas further south with shallower water where they can forage more efficiently. Because only a small percentage of the area where Wood Stork bands were recovered in our study is currently protected, measures are needed to prevent habitat destruction and preserve wetland habitats used by Wood Storks during the post‐breeding period in southern Brazil and Argentina.  相似文献   
103.
A rather large body of literature now exists on the use of telemental health services in the diagnosis and management of various psychiatric conditions. This review aims to provide an up‐to‐date assessment of telemental health, focusing on four main areas: computerized CBT (cCBT), Internet‐based CBT (iCBT), virtual reality exposure therapy (VRET), and mobile therapy (mTherapy). Four scientific databases were searched and, where possible, larger, better‐designed meta‐analyses and controlled trials were highlighted. Taken together, published studies support an expanded role for telepsychiatry tools, with advantages that include increased care access, enhanced efficiency, reduced stigma associated with visiting mental health clinics, and the ability to bypass diagnosis‐specific obstacles to treatment, such as when social anxiety prevents a patient from leaving the house. Of technology‐mediated therapies, cCBT and iCBT possess the most efficacy evidence, with VRET and mTherapy representing promising but less researched options that have grown in parallel with virtual reality and mobile technology advances. Nonetheless, telepsychiatry remains challenging because of the need for specific computer skills, the difficulty in providing patients with a deep understanding or support, concerns about the “therapeutic alliance”, privacy fears, and the well documented problem of patient attrition. Future studies should further test the efficacy, advantages and limitations of technology‐enabled CBT, as well as explore the online delivery of other psychotherapeutic and psychopharmacological modalities.  相似文献   
104.
Summary A rapid procedure for plating the thermo-acidophilic archaebacterium Sulfolobus solfataricus using Gerlite as a gelling agent is reported. The technique uses a clear, single layer in which the colonies are grown.  相似文献   
105.
Abstract Five non-motile Gram-positive cocci were isolated from saline located in geothermal regions of the Antarctic continent. The organisms were extremely halotolerant growing between 0 and 4.2 M NaCl. On the basis of the results of phenotypic characterizations, lipid and quinone analyses, and the amino acid composition of the cell the isolates have been assigned to the genus Micrococcus .  相似文献   
106.
We isolated 11 polymorphic microsatellite loci for wood stork (Mycteria americana). Polymerase chain reaction (PCR) primers and conditions are described for the amplification of five dinucleotide, one trinucleotide and five tetranucleotide microsatellite loci. The PCR primers were tested on two wood stork populations, Fazenda Ipiranga, Mato Grosso, Brazil (n = 11) and Tamiami West, Everglades, Florida, USA (n = 20). The primers yielded two to four alleles per locus, an observed heterozygosity of 0.0–0.727 and a polymorphic information content of 0.048–0.604. The low level of polymorphism for these markers is consistent with previous studies of this species.  相似文献   
107.
A range of recombinant strains of Escherichia coli were developed to produce 1,3-propanediol (1,3-PDO), an important C3 diol, from glucose. Two modules, the glycerol-producing pathway converting dihydroxyacetone phosphate to glycerol and the 1,3-PDO-producing pathway converting glycerol to 1,3-PDO, were introduced into E. coli. In addition, to avoid oxidative assimilation of the produced glycerol, glycerol oxidative pathway was deleted. Furthermore, to enhance the carbon flow to the Embden- Meyerhof-Parnas pathway, the Entner-Doudoroff pathway was disrupted by deleting 6-phosphogluconate dehydratase and 2-keto-3-deoxy-6-phosphogluconate aldolase. Finally, the acetate production pathway was removed to minimize the production of acetate, a major and toxic by-product. Flask experiments were carried out to examine the performance of the developed recombinant E. coli. The best strain could produce 1,3-PDO with a yield of 0.47 mol/mol glucose. Along with 1,3-PDO, glycerol was produced with a yield of 0.33 mol/mol glucose.  相似文献   
108.
We report three families with dominant unilateral renal adysplasia without vesico-ureteral reflux. No dysmorphia or anomalies were evident in the reproductive system. Ophthalmological examination excluded the presence of optic nerve coloboma or other ocular anomalies. No mutations were detected in the EMX(2) and in PAX(2) genes of affected members. Other homeobox genes could be responsible for this anomaly in these three families.  相似文献   
109.
110.
CD4 down-modulation is essential for the production of human immunodeficiency virus (HIV) infectious particles. Disease progression correlates with enhanced viral induced CD4 down-modulation, and a subset of long-term nonprogressors carry viruses defective in this function. Despite multiple pieces of evidence highlighting the importance of this function in viral pathogenesis in vivo, to date, HIV-induced CD4 down-modulation has not been used as a target for intervention. We describe here HIV-based vectors that deliver truncated CD4 molecules resistant to down-modulation by the viral products Nef and Vpu. Infection of cells previously transduced with these vectors proceeded normally, and viral particles were released in normal amounts. However, the infectivity of the released virions was reduced 1,000-fold. Lentiviral vectors expressing truncated CD4 molecules were efficient at blocking HIV-1 infectivity and replication in several cell lines and in CD4-positive primary lymphocytes. The findings presented here provide proof-of-principle that approaches targeting the virus-induced CD4 down-modulation may constitute the basis for novel anti-HIV therapies.  相似文献   
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