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Rogrio O. Souza Marco A. Del Lama Marcelo Cervini Norma Mortari Thomas Eltz Yvonne Zimmermann Carola Bach Berry J. Brosi Sevan Suni J. Javier G. Quezada‐Eun Robert J. Paxton 《Evolution; international journal of organic evolution》2010,64(11):3318-3326
Allozyme analyses have suggested that Neotropical orchid bee (Euglossini) pollinators are vulnerable because of putative high frequencies of diploid males, a result of loss of sex allele diversity in small hymenopteran populations with single locus complementary sex determination. Our analysis of 1010 males from 27 species of euglossine bees sampled across the Neotropics at 2–11 polymorphic microsatellite loci revealed only five diploid males at an overall frequency of 0.005 (95% CIs 0.002–0.010); errors through genetic nondetection of diploid males were likely small. In contrast to allozyme‐based studies, we detected very weak or insignificant population genetic structure, even for a pair of populations >500 km apart, possibly accounting for low diploid male frequencies. Technical flaws in previous allozyme‐based analyses have probably led to considerable overestimation of diploid male production in orchid bees. Other factors may have a more immediate impact on population persistence than the genetic load imposed by diploid males on these important Neotropical pollinators. 相似文献
233.
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
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The poliovirus nonstructural protein-encoding genes have been cloned and expressed in Escherichia coli using the inducible system described by Studier and Moffat [J. Mol. Biol. 189 (1986) 113-130] and Studier [J. Mol. Biol. 219 (1991) 37-44]. The two genes encoding the poliovirus proteases, 2Apro and 3Cpro, were cloned together with their flanking regions in order to test the ability of the polyprotein precursors synthesized to cause proteolytic cleavage and generate mature forms. Both proteases were synthesized and showed activity upon induction in this system. Previously, it had not been possible to produce the three poliovirus nonstructural proteins, 2B, 2C and 3A, and some of their precursors, 2C3AB, 2C3A and 3AB, at high levels in E. coli cells. We report the cloning of their genes using PCR techniques and their efficient expression from pET vectors upon induction with IPTG (isopropyl-beta-D-thiogalactopyranoside). Moreover, some of these proteins, e.g., 3AB, 3A and 2B, are quite toxic for E. coli cells and lysed them upon production. Our results demonstrate the usefulness of this inducible system using the pET vectors to express these toxic poliovirus proteins. 相似文献
236.
Valeria Calandrelli Agata Gambacorta Ida Romano Vito Carratore Licia Lama 《World journal of microbiology & biotechnology》2008,24(10):2269-2275
A novel thermo-alkali-stable catalase–peroxidase from Oceanobacillus oncorhynchi subsp. incaldaniensis subsp. nov., strain 20AG, was purified and characterized. The protein purified from the cells resulted in 110-fold purification
with a specific activity of 35,000 U/mg. The enzyme consisted of four identical subunits of 72 kDa as determined by SDS-PAGE
and the total molecular mass measured by gel filtration was 280 kDa. The heme content was determined to be 1 heme per homodimer.
The enzyme showed a Soret peak at 406 nm in the oxidized form and was easily reduced by dithionite. The enzyme showed an appreciable
peroxidase activity in addition to high catalase activity. The behaviour of this heme-enzyme was typical of the class of prokaryotic
catalase–peroxidases, which are sensitive to cyanide and insensitive to the eukaryotic catalase inhibitor 3-amino-1,2,4-triazole.
The enzyme was active over a temperature range from 30 to 60°C and a pH range from 5 to 10, with an optimum pH about 9.0 and
an optimum temperature of 40°C. The enzyme was stable in the pH range of 5.0 to 10.0 after 1 h of treatment at 40°C. The enzyme
was stable for 24 h at 40°C with a half-life of 4 h 60°C. The enzyme had a K
m of 24 mM for hydrogen peroxide. The amino terminal amino acid sequence of the catalase–peroxidase from strain 20AG was SEKRKMTTAFGA
and it showed no homology with other catalases. 相似文献
237.
The magnetic behaviour of erythrocytes from patients suffering from beta thalassemia major was investigated. All samples exhibited diamagnetic behaviour. Measurements were made before and after blood transfusion treatment. We suggest that the amount of blood given to the patient should be controlled in a way that the diamagnetic susceptibility after blood transfusion should be equal to that for the normal erythrocytes. In this way a specific range of haemoglobin level (Hgb) should be maintained when the patient is subjected to long-term hypertransfusional treatment. 相似文献
238.
Genaro C. Miranda-de la Lama Wilmer S. Sepúlveda Morris Villarroel Gustavo A. María 《Journal of applied animal welfare science : JAAWS》2013,16(2):109-123
Livestock vehicle accidents are rare but involve significant economic, human, and nonhuman farm animal losses. This study obtained information on the characteristics of accidents, the animals involved, and injuries to humans from newspaper reports about livestock vehicle accidents in Spain from January 2000 to December 2008. Most accidents involved pig transport (57%), followed by bovine (30%), poultry (8%), and sheep (5%). Driver mortality was not high (6%), and most accidents (76%) involved only the livestock vehicle, which often was overturned (64%) on a straight road transect (51%). Multivariate analysis of the data suggests 2 types of accidents, depending on the species transported. In the first cluster, 95.3% of the cases involved pig transport with articulated vehicles (60.5%). In the second cluster, 94.4% of the accidents involved small vehicles used for cattle transport (44.4%). The results of this study indicate that the characteristics of livestock vehicle accidents vary according to species. One of the main causes of accidents appears to be driver fatigue, which may be due to several factors such as intense workdays, poorly designed route plans, or high levels of pressure from companies. 相似文献
239.