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1.
Summary Details are given of a study of blood samples from 24 patients with Hb H disease from different Mediterranean countries and from the Far East. Four different types of -thal-1 (--) were observed, namely-() ( 20.5-kb deletion);--MED-I ( 17.5-kb deletion);--MED-II (>26.5-kb deletion); and--SEA ( 18-kb deletion, in Orientals only). The -thal-2 was mainly of the deletion type (16 with the 3.7-kb deletion; 1 with the 4.2-kb deletion), while 4 of the 7 patients with a nondeletional type had the five-nucleotide deletion at the donor splice site of the first intron of the 2 gene. All patients had a mild-to-moderate hemolytic anemia; no significant differences in hematology were observed between the groups. Hb A2 was decreased to about one-third of the normal level. The Hb H formation varied considerably and its quantitation was not always satisfactory. Patients with Hb H disease due to any -thal-1 combined with a nondeletional -thal-2 had the highest Hb H levels and a more marked anemia. The chain production was small and absent in patients with the MED-II type of -thal-1 because this deletion included the and genes. The highest chain levels were present in the four patients with the SEA type of -thal-1. The chain production was increased, particularly in patients with a mutation of C T at position-158 to the G globin gene. This chain was primarily present as Hb Bart's (or 4) and only about 15% was recovered as Hb F or 22. The evaluation of the rate of chains produced in these patients was greatly facilitated by data from one patient who had Hb H disease and a heterozygosity for the A-+. The low levels of Hb A2 and of Hb F (relative to Hb Bart's) can be explained by a decreased affinity of chains for and chains as compared with chains in conditions of severe chain deficiency.  相似文献   
2.
Aluminum is an abundant metal in the earth’s crust that turns out to be toxic in acidic environments. Many plants are affected by the presence of aluminum at the whole plant level, at the organ level, and at the cellular level. Tobacco as a cash crop (Nicotiana tabacum L.) is a widely cultivated plant worldwide and is also a good model organism for research. Although there are many articles on Al-phytotoxicity in the literature, reviews on a single species that are economically and scientifically important are limited. In this article, we not only provide the biology associated with tobacco Al-toxicity, but also some essential information regarding the effects of this metal on other plant species (even animals). This review provides information on aluminum localization and uptake process by different staining techniques, as well as the effects of its toxicity at different compartment levels and the physiological consequences derived from them. In addition, molecular studies in recent years have reported specific responses to Al toxicity, such as overexpression of various protective proteins. Besides, this review discusses data on various organelle-based responses, cell death, and other mechanisms, data on tobacco plants and other kingdoms relevant to these studies.  相似文献   
3.
The oomycete Albugo candida causes white rust of Brassicaceae, including vegetable and oilseed crops, and wild relatives such as Arabidopsis thaliana. Novel White Rust Resistance (WRR) genes from Arabidopsis enable new insights into plant/parasite co-evolution. WRR4A from Arabidopsis accession Columbia (Col-0) provides resistance to many but not all white rust races, and encodes a nucleotide-binding, leucine-rich repeat immune receptor. Col-0 WRR4A resistance is broken by AcEx1, an isolate of A. candida. We identified an allele of WRR4A in Arabidopsis accession Øystese-0 (Oy-0) and other accessions that confers full resistance to AcEx1. WRR4AOy-0 carries a C-terminal extension required for recognition of AcEx1, but reduces recognition of several effectors recognized by the WRR4ACol-0 allele. WRR4AOy-0 confers full resistance to AcEx1 when expressed in the oilseed crop Camelina sativa.  相似文献   
4.
Y2Zr2O7‐doped with Eu3+ and Sm3+ phosphors were prepared for the first time as multifunctional smart materials using a solid‐state reaction method at 1400oC. Thermal behaviour, crystal structure, surface morphology, and elemental analysis were characterized using thermogravimetric (TG) and differential thermal (DTA) analyses, X‐ray diffraction (XRD) and scanning electron microscope equipped with energy‐dispersive X‐ray spectroscopy (SEM‐EDX). Experimental results revealed that both phosphors have a pyrochlore structure with a cubic crystal system. Photoluminescence properties were also measured and red emission was observed from Y1.90Eu0.10Zr2O7 and Y1.90Sm0.10Zr2O7 phosphors. Dielectric constant, loss tangent, piezoelectric charge constant, and Curie temperature of all the samples were determined using an LCR‐meter, d33‐meter, and TG/DTA. Eu doping in Y2Zr2O7 resulted in a high dielectric constant (9.61) and low loss tangent (1.67%) values, whereas high piezoelectric charge constant (0.68 pC/N) and high Curie temperature (820°C) could be obtained using Sm‐doped Y2Zr2O7.  相似文献   
5.
6.
This paper presents the work conducted on the chemical constituents of some common and widely distributed halophyte taxa from Cyprus with the aim that these studies will help in the evaluation of halophytes for different economical purposes. The plant species of Crithmum maritimum L., Limbarda crithmoides (L.) Dumort, Atriplex portulacoides L., Salsola kali L., Atriplex halimus L., Limonium oleifolium Mill., L. meyeri (Boiss.) Kuntze; and Tetraena alba (L.f.) Beier & Thulin were collected in the middle of July. The shoot tissue and leaf samples were collected from the natural habitats and left for drying under air circulation followed by placing them in oven at 60 °C for 96 hours. The material was crushed using mortar and pestle and subjected to an analysis of macro- and micro-nutrients and biochemical compounds. K+/Na+ in the leaf tissues of the dicot species showed relatively high values depicting their behavior as Na+ includes but very low Cl- levels were recorded. Out of the species investigated here in 4 TFAA content was rather high. Values ranging from 0.5% to 1% dry weight were exhibited in one species. However, only 3 species showed very low TFAA values. Later may be due to low nitrogen availability in their environment. The phenetic analyses of eight halophyte species performed on the data matrix using Ntsys-pc program version 2.1 revealed that, cluster analysis of the overall results obtained here leads to 2 clusters. This discrimination appears to be as a result of their different abilities to accumulate either proline or glycine betaine.  相似文献   
7.
For the last 10 years our laboratory has been studying the proliferation, migration and differentiation of neuronal progenitor cells located in the anterior part of the postnatal forebrain subventricular zone (SVZa). SVZa-derived cells possess a number of proliferative characteristics that distinguish them from the other progenitor cells in the central nervous system. This review summarizes our recent findings, in which we compared the pattern of cell cycle inhibitory proteins expressed by the neonatal SVZa to that of telencephalic ventricular zone cells.  相似文献   
8.
The effects of streptozotocin-induced diabetes on brucellosis of rats   总被引:2,自引:0,他引:2  
It is believed that an infection is more common and runs a more protracted course in people with diabetes. In clinical practice, it is important to be aware of these associations, as the prognosis is often dependent upon prompt recognition and appropriate treatment. To show the course of brucellosis in the diabetic state, a model of Brucella melitensis infection was used in the setting of streptozotocin-induced diabetes in rat. B. melitensis infection proceeded more severely in diabetic rats and the severity of diabetes affected the prognosis. However, no association was found between B. melitensis and insulin using in vitro and in vivo experiments. Our study illustrates that B. melitensis infection in diabetes should be taken seriously.  相似文献   
9.
BackgroundWe are witnessing the growth of urban populations, particularly in the developing world. São Paulo, the largest city in South America, continues to grow, and this growth is dramatically effecting the environment and human health. The aim of this study was to estimate the point prevalence of chronic pain in São Paulo city dwellers and to explore the influence of aspects related to urbanicity.MethodsA two-stage cluster randomized sample included 1100 individuals of the city of Sao Paulo, representing the population proportionally in terms of gender, age and social classes in 2007. For this observational cross-sectional study, the household sample was interviewed using validated questionnaires for sociodemographic aspects, the Beck inventories for anxiety and depression, the WHOQoL-REF for quality of life, the Chalder Fatigue Scale. Musculoskeletal pain was defined as diffuse pain or pain located in the back, joints or limbs. Data regarding sleep complaints and polysomnography were obtained from the Epidemiologic Sleep Study conducted in São Paulo city in 2007.ResultsThe prevalence estimate of chronic musculoskeletal pain was approximately 27%, with a female/male ratio of approximately 2.6/1. The predictors were being in the age-range of 30–39 years, low socioeconomic and schooling levels, obesity, sedentarism, fatigue, non-restorative sleep, daytime sleepiness, poor sleep quality, poor life quality, anxiety and depression symptoms. Psychological wellbeing was the main discriminator between responders with chronic musculoskeletal pain and the controls, followed by depression for the participants with poor psychological wellbeing, and fatigue, for the remaining ones. Insomnia syndrome was the third-level discriminator for those with fatigue, whereas sleep quality for those without fatigue.ConclusionsMusculoskeletal pain was frequently reported by São Paulo city dwellers and its correlates with psychological and sleep aspects are suggestive of a response to urbanicity.

Trial Registration

ClinicalTrials.gov NCT00596713  相似文献   
10.
Most nonsyndromic hearing losses are caused by mutations in the GJB2 gene, and studies have revealed that the forms and frequencies of these mutations are largely dependent on ethnic origin. In the present study, we aimed to characterize the mutation profiles of 151 patients with hearing loss in Turkey. The entire coding region of the GJB2 was directly sequenced in all patients. We found 35 (23.2%) individuals carrying GJB2 mutations. Seven different mutations were identified, five of which were previously known (35delG, delE120, R184P, M163V, L90P), the remaining two being novel variants (M34V, L205V). The most common mutation was 35delG followed by delE120. The 35delG mutation was homozygous in 22 cases (14.5%) and heterozygous in 4 cases (2.6%). Compound heterozygosity for 35delG was also observed. The delE120 mutation was found in three patients in homozygous form. A homozygous L90P and heterozygous mutations M163V and M34V were found in single cases.  相似文献   
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