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1.
Mitochondrial DNA evolution in the genus Equus 总被引:7,自引:0,他引:7
Employing mitochondrial DNA (mtDNA) restriction-endonuclease maps as the
basis of comparison, we have investigated the evolutionary affinities of
the seven species generally recognized as the genus Equus. Individual
species' cleavage maps contained an average of 60 cleavage sites for 16
enzymes, of which 29 were invariant for all species. Based on an average
divergence rate of 2%/Myr, the variation between species supports a
divergence of extant lineages from a common ancestor approximately 3.9 Myr
before the present. Comparisons of cleavage maps between Equus przewalskii
(Mongolian wild horse) and E. caballus (domestic horse) yielded estimates
of nucleotide sequence divergence ranging from 0.27% to 0.41%. This range
was due to intraspecific variation, which was noted only for E. caballus.
For pairwise comparisons within this family, estimates of sequence
divergence ranged from 0% (E. hemionus onager vs. E. h. kulan) to 7.8% (E.
przewalskii vs. E. h. onager). Trees constructed according to the parsimony
principle, on the basis of 31 phylogenetically informative restriction
sites, indicate that the three extant zebra species represent a
monophyletic group with E. grevyi and E. burchelli antiquorum diverging
most recently. The phylogenetic relationships of E. africanus and E.
hemionus remain enigmatic on the basis of the mtDNA analysis, although a
recent divergence is unsupported.
相似文献
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A virus isolated from turnip in Aligarh, India, which caused mild mosaic, mottling and curling of leaves followed by overall stunting of plants, was characterized as potato virus X (PVX) on the basis of its host range, biological and physical properties, particle morphology, ultrastructural studies, and serological relationship. 相似文献
4.
Masoodifar Mahsa Hajihashemi Saeed Pazhoohan Saeed Nazemi Samad Mojadadi Mohammad-Shafi 《Purinergic signalling》2021,17(1):143-150
Purinergic Signalling - Recent studies have shown that mesenchymal stem cells (MSCs) and their conditioned medium (CM) have potential therapeutic effects in animal models of neuropathic pain (NP).... 相似文献
5.
Haider Karar Muhammad Amjad Bashir Reem Atalla Alajmi Dina M. Metwally Muneeba Haider Najeeba Haider Samad Raza Ali Bakhsh Rania Haddadi 《Saudi Journal of Biological Sciences》2021,28(7):3936-3942
In 2004–05, during the December to February about 141 mango farmers were interviewed during peak activity of mango mealy bug in southern Punjab, Pakistan. The objective was to know the farmers’ knowledge, perceptions and practices in the management of mango mealy bug. Most of the farmers (94.33%) reported that Chaunsa variety (king of all mango varieties) was susceptible to mango and irrigation water was the major source of flare up of this pest. Basudin and Supracide were the most commonly used insecticides as 72.92 and 51.77 percent farmers gave positive response and grease bands were applied for the control of mango mealy bug by the majority of the respondents. Hundred percent yield losses was told by 22.7 percent respondents whereas 75 percent, 50 percent and 25 percent losses were reported by 39.7, 31.9 and 14.2 insecticidal spray did not show satisfaction to the respondents for the control of fertilized females of mango mealy bug coming down from the trees. Lack of knowledge about the pest, lack of money, adulterated and shortage of pesticides, lack of unity amongst farmers Further the growers’ views were tested in the field for confirmation and small land holdings were the main constraints for the control of mango mealy bug. 相似文献
6.
Rapeephan R. Maude Md Amir Hossain Mahtab Uddin Hassan Sophie Osbourne Katherine Langan Abu Sayeed Mohammed Rezaul Karim Rasheda Samad Shyamanga Borooah Bal Dhillon Nicholas P. J. Day Arjen M. Dondorp Richard J. Maude 《PloS one》2013,8(12)
Introduction
Measurement of optic nerve sheath diameter (ONSD) by ultrasound is increasingly used as a marker to detect raised intracranial pressure (ICP). ONSD varies with age and there is no clear consensus between studies for an upper limit of normal. Knowledge of normal ONSD in a healthy population is essential to interpret this measurement.Methods
In a prospective observational study, ONSD was measured using a 15 MHz ultrasound probe in healthy volunteers in Chittagong, Bangladesh. The aims were to determine the normal range of ONSD in healthy Bangladeshi adults and children, compare measurements in males and females, horizontal and vertical beam orientations and left and right eyes in the same individual and to determine whether ONSD varies with head circumference independent of age.Results
136 subjects were enrolled, 12.5% of whom were age 16 or under. Median ONSD was 4.41 mm with 95% of subjects in the range 4.25–4.75 mm. ONSD was bimodally distributed. There was no relationship between ONSD and age (≥4 years), gender, head circumference, and no difference in left vs right eye or horizontal vs vertical beam.Conclusions
Ultrasonographic ONSD in Bangladeshi healthy volunteers has a narrow bimodal distribution independent of age (≥4 years), gender and head circumference. ONSD >4.75 mm in this population should be considered abnormal. 相似文献7.
Sophie Borgella Nadine Fievet Bich-Tram Huynh Samad Ibitokou Gbetognon Hounguevou Jacqueline Affedjou Jean-Claude Sagbo Parfait Houngbegnon Blaise Guezo-Mévo Achille Massougbodji Adrian J. F. Luty Michel Cot Philippe Deloron 《PloS one》2013,8(11)
Background
Infants of mothers with placental Plasmodium falciparum infections at delivery are themselves more susceptible to malaria attacks or to infection in early life.Methodology/ Principal Findings
To assess the impact of either the timing or the number of pregnancy-associated malaria (PAM) infections on the incidence of parasitemia or malaria attacks in infancy, we followed 218 mothers through pregnancy (monthly visits) up to delivery and their infants from birth to 12 months of age (fortnightly visits), collecting detailed clinical and parasitological data. After adjustment on location, mother’s age, birth season, bed net use, and placental malaria, infants born to a mother with PAM during the third trimester of pregnancy had a significantly increased risk of infection (OR [95% CI]: 4.2 [1.6; 10.5], p = 0.003) or of malaria attack (4.6 [1.7; 12.5], p = 0.003). PAM during the first and second trimesters had no such impact. Similarly significant results were found for the effect of the overall number of PAM episodes on the time to first parasitemia and first malaria attack (HR [95% CI]: 2.95 [1.58; 5.50], p = 0.001 and 3.19 [1.59; 6.38], p = 0.001) respectively.Conclusions/ Significance
This study highlights the importance of protecting newborns by preventing repeated episodes of PAM in their mothers. 相似文献8.
The consequence of harvesting young leaves of cassava as vegetable on the vulnerability of the crop to cassava mosaic disease (CMD) and on storage root yield was investigated using 30 cassava genotypes planted in IITA fields located in the humid forest (Port Harcourt?:?Onne), forest-savannah transition (Ibadan), southern guinea savannah (Mokwa) and northern guinea savannah (Zaria) agroecologies in Nigeria. Tender apical leaves and shoots of the cassava genotypes were removed from forty plants per cassava genotype with the same number of plants considered as control. Whitefly infestation, disease incidence (DI) and symptom severity (ISS) of the disease were assessed at monthly interval for six months and also at the ninth month after planting (MAP). Yield reduction due to this treatment was calculated as percentage harvest index (HI). Whitefly population fluctuated throughout the period of observation at all locations with higher population obtained generally for treated plants compared to control plants. Sprouting leaves of some treated genotypes were observed with severe mosaic symptoms, while corresponding control showed no mosaic symptoms. Contrarily, no remarkable difference was observed in Zaria between the mean ISS of treated and control cassava genotypes. There was a highly significant difference (P?<?0.01) in DI and ISS among cassava genotypes across all locations. Also, there was a highly significant interaction (P?<?0.01) in symptom severity between location (loc) and genotype, genotype and treatment (trt), loc and trt. Interaction between loc, genotypes and trt with regard to DI was highly significant at 2, 3 and 4 MAP, while with ISS, the interaction was highly significant all through the counting period. There was a positive relationship between DI and ISS on plants of genotypes 96/1039 and ISU. The percentage HI (27.4) of treated plants of genotype 95/0166 in Ibadan was remarkably lower than the value obtained for corresponding control (41.9) plants. Also, sharp distinction in% HI of treated (39.5) and control (43.8) ISU was observed in Onne with their respective ISS values as 3.7 and 3.2. Therefore, harvesting tender apical leaves and shoots of cassava as vegetables should be discouraged as it increases the severity of CMD infection in the regenerating shoots of cassava with attendant storage root yield reduction. 相似文献
9.
Cline MS Smoot M Cerami E Kuchinsky A Landys N Workman C Christmas R Avila-Campilo I Creech M Gross B Hanspers K Isserlin R Kelley R Killcoyne S Lotia S Maere S Morris J Ono K Pavlovic V Pico AR Vailaya A Wang PL Adler A Conklin BR Hood L Kuiper M Sander C Schmulevich I Schwikowski B Warner GJ Ideker T Bader GD 《Nature protocols》2007,2(10):2366-2382
Cytoscape is a free software package for visualizing, modeling and analyzing molecular and genetic interaction networks. This protocol explains how to use Cytoscape to analyze the results of mRNA expression profiling, and other functional genomics and proteomics experiments, in the context of an interaction network obtained for genes of interest. Five major steps are described: (i) obtaining a gene or protein network, (ii) displaying the network using layout algorithms, (iii) integrating with gene expression and other functional attributes, (iv) identifying putative complexes and functional modules and (v) identifying enriched Gene Ontology annotations in the network. These steps provide a broad sample of the types of analyses performed by Cytoscape. 相似文献
10.