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101.
102.
Ishtiaq F Beadell JS Baker AJ Rahmani AR Jhala YV Fleischer RC 《Proceedings. Biological sciences / The Royal Society》2006,273(1586):587-594
The success of introduced species is frequently explained by their escape from natural enemies in the introduced region. We tested the enemy release hypothesis with respect to two well studied blood parasite genera (Plasmodium and Haemoproteus) in native and six introduced populations of the common myna Acridotheres tristis. Not all comparisons of introduced populations to the native population were consistent with expectations of the enemy release hypothesis. Native populations show greater overall parasite prevalence than introduced populations, but the lower prevalence in introduced populations is driven by low prevalence in two populations on oceanic islands (Fiji and Hawaii). When these are excluded, prevalence does not differ significantly. We found a similar number of parasite lineages in native populations compared to all introduced populations. Although there is some evidence that common mynas may have carried parasite lineages from native to introduced locations, and also that introduced populations may have become infected with novel parasite lineages, it may be difficult to differentiate between parasites that are native and introduced, because malarial parasite lineages often do not show regional or host specificity. 相似文献
103.
The purpose of this study was to investigate the potential of immobilized lead- and cadmium-resistant Pseudomonas putida strain PT to remove heavy metals from aqueous medium under extreme conditions. The tolerance and accumulation of cadmium and lead ions by strain PT were investigated by minimal inhibitory concentration (MIC) determination and polymerase chain reaction (PCR) of cadA gene, respectively. The surface chemical functional groups of P. putida PT involved in the metal biosorption were identified by Fourier transform infrared (FTIR). Pseudomonas putida PT was immobilized in three matrices include carboxy-methyl cellulose (CMC), rice bran, and a new composite made of alginate, polyvinyl alcohol (PVA), and CaCO3 to prepare heavy metal adsorbent. The biosorbents were analyzed by SEM, and their metal removal capability was assayed in two consecutive cycles by atomic absorption spectroscopy. The viability of immobilized bacterial cells was determined by flow cytometry during storage at 4 °C and exposure to the environmental stresses (pH and temperature). The results showed that PT strain was resistant up to 10 mM Pb2+ and 8 mM Cd2+. FTIR analysis revealed that alcohol, sulfur, phosphate, esters, and amide groups played important roles in metal biosorption process and, also change in metabolic reactions like hydration and polyesters accumulation was observed after metal biosorption. The presence of cadA gene, a heavy metal translocating pump-coding gene, indicated the ability of metals bioaccumulation by the PT strain. Immobilized cells in alginate–PVA–CaCO3 and rice bran showed the highest metal removal efficiency for Pb2+ as 75% and Cd2+ as 96.7%, respectively. Metal adsorbents were reusable, and the highest removal efficiency in the second cycle was observed in inoculated alginate–PVA–CaCO3 (79.5% Pb2+ and 45% Cd2+). Flow cytometric analysis represented that the immobilized cell viability was retained (<?97%) after 4 weeks storage at 4 °C. Viability under two environmental stresses in all matrices was as follows: <?96% at 25 °C, <?87% at 45 °C, <?85% at pH 4,?<?96% at pH 7, and?<?89% at pH 11. The results signify that these metal adsorbents are efficient technological tools for bioremediation even in harsh environmental conditions. 相似文献
104.
105.
S Jahan S Singh A Srivastava V Kumar D Kumar A Pandey CS Rajpurohit AR Purohit VK Khanna AB Pant 《Molecular neurobiology》2018,55(4):2828-2839
106.
107.
Possible repurposing of pyrvinium pamoate for the treatment of mesothelioma: A pre‐clinical assessment 下载免费PDF全文
108.
Relationship between body fat and BMI in a US hispanic population‐based cohort study: Results from HCHS/SOL 下载免费PDF全文
William W. Wong Garrett Strizich Moonseong Heo Steven B. Heymsfield John H. Himes Cheryl L. Rock Marc D. Gellman Anna Maria Siega‐Riz Daniela Sotres‐Alvarez Sonia M. Davis Elva M. Arredondo Linda Van Horn Judith Wylie‐Rosett Lisa Sanchez‐Johnsen Robert C. Kaplan Yasmin Mossavar‐Rahmani 《Obesity (Silver Spring, Md.)》2016,24(7):1561-1571
109.
Goldstein DB; Zhivotovsky LA; Nayar K; Linares AR; Cavalli-Sforza LL; Feldman MW 《Molecular biology and evolution》1996,13(9):1213-1218
It has recently been suggested that observed levels of variation at
microsatellite loci can be used to infer patterns of selection in genomes
and to assess demographic history. In order to evaluate the feasibility of
these suggestions it is necessary to know something about how levels of
variation at microsatellite loci are expected to fluctuate due simply to
stochasticity in the processes of mutation and inheritance (genetic
sampling). Here we use recently derived properties of the stepwise mutation
model to place confidence intervals around the variance in repeat score
that is expected at mutation-drift equilibrium and outline a statistical
test for whether an observed value differs significantly from expectation.
We also develop confidence intervals for the time course of the buildup of
variation following a complete elimination of variation, such as might be
caused by a selective sweep or an extreme population bottleneck. We apply
these methods to the variation observed at human Y-specific
microsatellites. Although a number of authors have suggested the
possibility of a very recent sweep, our analyses suggest that a sweep or
extreme bottleneck is unlikely to have occurred anytime during the last
approximately 74,000 years. To generate this result we use a recently
estimated mutation rate for microsatellite loci of 5.6 x 10(-4) along with
the variation observed at autosomal microsatellite loci to estimate the
human effective population size. This estimate is 18,000, implying an
effective number of 4,500 Y chromosomes. One important general conclusion
to emerge from this study is that in order to reject mutation-drift
equilibrium at a set of linked microsatellite loci it is necessary to have
an unreasonably large number of loci unless the observed variance is far
below that expected at mutation-drift equilibrium.
相似文献
110.
W N Kuo M A Rahmani T Blake S Sen J L Dominguez K A Shabazz D J White J Nicholson K Puente P Shells 《Cytobios》1986,47(188):45-52
Basic protein factor I (BPFI was purified to homogeneity from bovine brain by boiling and trichloroacetic acid-precipitation of tissue homogenate, followed by DEAE-cellulose, Sephadex G-150, Affi-Gel-phenothiazine, and Bio-Gel P-6DG chromatographic procedures. The preparation appeared as a single protein band in the SDS-polyacrylamide gel electrophoresis with a minimal Mr of 13,200. The factor was a basic protein as indicated by an estimated isoelectric point of pH 8.3 and a high content of amino acids including arginine, histidine, lysine and others. In the absence of Mn2+, the factor stimulated the phosphoprotein phosphatases (PPase) from rabbit brains. Unlike histones or protamine, the factor was a poor substrate for megamodulin-dependent protein kinase. In addition, the factor did not interact significantly with E. coli megamodulin. 相似文献