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111.
BackgroundThe prevalence of Wuchereria bancrofti, which causes lymphatic filariasis (LF) in The Gambia was among the highest in Africa in the 1950s. However, surveys conducted in 1975 and 1976 revealed a dramatic decline in LF endemicity in the absence of mass drug administration (MDA). The decline in prevalence was partly attributed to a significant reduction in mosquito density through the widespread use of insecticidal nets. Based on findings elsewhere that vector control alone can interrupt LF, we asked the question in 2013 whether the rapid scale up in the use of insecticidal nets in The Gambia had interrupted LF transmission.ConclusionsWe conclude that LF transmission may have been interrupted in The Gambia through the extensive use of insecticidal nets for malaria control for decades. The growing evidence for the impact of malaria vector control activities on parasite transmission has been endorsed by WHO through a position statement in 2011 on integrated vector management to control malaria and LF.  相似文献   
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Broadly speaking proteomic studies are one of the various techniques of utmost importance for understanding complex biological processes that occur under inductive conditions and revealing the multidimensional aspects of Crocus sativus in biological systems. In order to get an insight into the molecular changes and to characterize the variations in protein expression of C. sativus, a detailed proteomic analysis on one-dimensional gel electrophoresis is one of the basic steps to accomplish. We have compared total protein profiles of C. sativus extracted by three different recipes and analyzed on 10% sodium dodecyl sulfate polyacrylamide gels. Gels were subjected to densitometric analysis for further characterization. Among three different protocols NP-40 extraction buffer recipe resulted in the extraction of proteins most efficiently with minimum background and streaking. There was maximum solubilization of proteins with high efficiency. Such a profile can be used for high precision analysis of differential protein expression. This work is an attempt to assist researchers in effective extraction of proteins from C. sativus. As a researcher faces a perplexing array of choices as where to start we describe a method based on our collective analysis of the different protein protocols. This paper presents a method that could be applied at the outset of any proteomic study.  相似文献   
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We studied the population structure and reproductive biology of the mudskipper Periophthalmus waltoni Koumans, 1941, living on the mudflats of bay of Hormozgan province, Persian Gulf. The specimens were haphazardly and monthly collected from August 2008 to July 2009. A total of 2060 fishes was sampled, sexed 690 of which 221 (32%) were males, and 469 (68%) females. The total length (TL) and weight relationship demonstrated growth in both sexes was isometric with the function W = 0.0078TL3.06. The asymptotic length (L∞) and growth coefficient (K) were estimated as 16.5 cm and 0.75 yr–1, respectively. Age of the fish at zero length (to) was calculated–0.35 and the longevity was attained 3.65 year. The estimated Von Bertalanffy function was TL(t) = 16.5[1–exp(–0.75(t + 0.35))]. Natural mortality (M) was estimated 1.74 yr–1. Four cohorts were distinguished annuallywith mean of TL = 7.35, 10.17, 12.74 and 13.92 cm. The maximum recruitment rate was in January at 17.5%. The overall sex ratio (F: M) (1: 0.49) was significantly different than 1: 1. The peak of the gonadosomatic index (GSI) occurred in February. The size at onset of sexual maturity (LM50)wasestimated at TL = 12 cm. The mean of absolute and relative fecundity were estimated as 3558 ± 2203 and 257 ± 101 eggs, respectively.  相似文献   
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A 04-year-old boy was referred to our institution with severe, progressive heart failure of 4-months duration associated with a persistent wide QRS tachycardia with left bundle branch block and severe left ventricular dysfunction. Because of incessant wide QRS tachycardia refractory to antiarrhythmic drugs, he was referred for electrophysiological study. The ECG was suggestive of VT arising from the right ventricle near the His area. Electrophysiological study revealed that origin of tachycardia was septum of the right ventricle, near His bundle, however the procedure was not successful and an inadvertent complete atrioventricular conduction block occurred. The same ventricular tachycardia recurred. A second procedure was performed with a retrograd aortic approach to map the left side of the interventricular septum. The earliest endocardial site for ablation was localized in the anterobasal region of left ventricle near His bundle. In this location, one radiofrequency pulse interrupted VT and rendered it not inducible. The echocardiographic evaluation showed partial reversal of left ventricular function in the first 3 months. The diagnosis was idiopathic parahisian left ventricular tachycardia leading to a tachycardia mediated cardiomyopathy, an extremely rare clinical picture in children.  相似文献   
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新疆哈纳斯自然保护区大型地衣初报   总被引:3,自引:1,他引:2  
报道新疆哈纳斯自然保护区大型地衣61种,2亚种,6变型;隶属于28属,14科,其中1属为半知地衣,5种为中国新记录,23种为新疆新分布。  相似文献   
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In vertebrate retina, rod outer segment is the site of visual transduction. The inward cationic current in the dark-adapted outer segment is regulated by cyclic GMP. A light flash on the outer segment activates a cyclic GMP phosphodiesterase resulting in rapid hydrolysis of the cyclic nucleotide which in turn causes a decrease in the dark current. Restoration of the dark current requires inactivation of the phosphodiesterase and synthesis of cyclic GMP. The latter is accomplished by the enzyme guanylate cyclase which catalyzes the formation of cyclic GMP from GTP. Therefore, factors regulating the cyclase activity play a critcal role in visual transduction. But regulation of the cyclase by some of these factors — phosphodiesterase, ATP, the soluble proteins and metal cofactors (Mg and Mn) — is controversial. The availability of different types of cyclase preparations, dark-adapted rod outer segments with fully inhibited phosphodiesterase activity, partially purified cyclase without PDE contamination, cloned rod outer segment cyclase free of other rod outer segment proteins, permitted us to address these controversial issues. The results show that ATP inhibits the basal cyclase activity but enhances the stimulation of the enzyme by soluble activator, that cyclase can be activated in the dark at low calcium concentrations under conditions where phosphodiesterase activity is fully suppressed, and that greater activity is observed with manganese as cofactor than magnesium. These results provide a better understanding of the controls on cyclase activity in rod outer segments and suggest how regulation of this cyclase by ATP differs from that of other known membrane guanylate cyclases.This work was supported by the grants from the National Institutes of Health (EY07158, EY 05230, EY 10828, NS 23744) and the equipment grant from Pennsylvania Lions Eye Research Foundation.  相似文献   
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