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221.
We recently re-examined a case of Visceral Leishmaniasis, in a 36-year-old caucasian immune-competent men with an unusual clinical presentation. Together with symptoms and signs of a severe acute liver involvement, he presented weight loss, huge spleen enlargement, pancytopenia and increased ?-globulin serum level with a high polyclonal peak. He had no fever, but over-abundant night sweats were frequent. The patient was considered to have liver cirrhosis, and the diagnosis of visceral leishmaniosis was made with a year's delay. From this case report we may learn that, despite an unusual clinical presentation, the diagnosis of visceral leishmaniasis should not be excluded when other characteristic signs and symptoms and laboratory abnormalities are present. 相似文献
222.
223.
Background
The frequency of a haplotype comprising one allele at each of two loci can be expressed as a cubic equation (the 'Hill equation'), the solution of which gives that frequency. Most haplotype and linkage disequilibrium analysis programs use iteration-based algorithms which substitute an estimate of haplotype frequency into the equation, producing a new estimate which is repeatedly fed back into the equation until the values converge to a maximum likelihood estimate (expectation-maximisation). 相似文献224.
Purified chloroplast tRNAs were isolated fromPisum sativum leaves and radioactively labeled at their 3′ end using tRNA nucleotidyl transferase and α32P-labeled CTP. Pea ctDNA was fragmented using a number of restriction endonucleases and hybridized with thein vitro labeled chloroplast tRNAs by DNA transfer method. Genes for tRNAs have been found to be dispersed throughout the chloroplast
genome. A closer analysis of the several hybrid regions using recombinant DNA plasmids have shown that tRNA genes are localized
in the chloroplast genome in both single and multiple arrangements. Two dimensional gel electrophoresis of total ct tRNA have
identified 36 spots. All of them have been found to hybridize withPisum sativum ctDNA. Using recombinant clones, 30 of the tRNA spots have been mapped inPisum sativum ctDNA. 相似文献
225.
L. Giorgetti M. R. Vergara M. Evangelista F. Lo Schiavo M. Terzi V. Nuti Ronchi 《Molecular & general genetics : MGG》1995,246(6):657-662
During the establishment of an embryogenic cell line from a carrot hypocotyl explant, processes closely resembling meiotic divisions are seen. A microdensitometric analysis revealed that the amount of cellular DNA diminished in the majority of cells to the haploid level. However, the diploid level was re-established in a matter of a few days. The genetic consequences of this segregation were studied by analyzing restriction fragment length polymorphisms (RFLP) and randomly amplified polymorphic DNAs (RAPD). The results showed that the great majority of embryos regenerated from segregants and that different segregants had different genetic constitutions. 相似文献
226.
Judith C.W. Mak Mara Astolfi Xiao-Ling Zhang Stefano Evangelista Stefano Manzini Peter J. Barnes 《Peptides》1996,17(8):1389-1395
An autoradiographic technique was used to study the distribution of changes in pulmonary NK1 and NK2 receptors in guinea pig lung after repeated antigen challenge. Specific labeling of [3H] CP96345 (NK1 receptors) and [3H] SR48968 (NK2 receptors) was localized over the tracheal and bronchial smooth muscle; the density of binding increased towards smaller airways with a higher density for [3H] CP96345 binding. Bronchial epithelium and pulmonary blood vessels were also labeled densely with [3H] CP96345. No remarkable difference in the pattern of distribution of pulmonary NK1 and NK2 tachykinin receptors was observed between control, vehicle-challenged, and repeatedly antigen-challenged (weekly for three times) guinea pigs. A significant reduction in specific labeling of [3H] CP96345 (p < 0.01) and [3H] SR48968 (p < 0.05) over pulmonary structures was observed in antigen-challenged compared to control or vehicle-challenged animals. This study provides evidence that NK1 and NK2 tachykinin receptors are both localized to smooth muscle of all sizes in guinea pig airways and provides further evidence for a discrete distribution of NK1 and NK2 tachykinin receptors, consistent with their relative functional activities. In a established model of airway inflammation a decrease in the expression of NK1 and NK2 tachykinin receptors was evident on several different cell types within the lung, and this could influence airway and vascular reactivity. 相似文献
227.
Analogs of neurokinin A(4-10) afford protection against gastroduodenal ulcers in rats 总被引:4,自引:0,他引:4
We have developed a novel series of peptides, related to the NKA(4-10) sequence, in which substitution of selected amino acids determined variations in the affinity for the TK receptor subtypes. Subcutaneous pretreatment of rats with some peptides of this series reduced gastric ulcers induced by ethanol, indomethacin or acetylsalicylic acid (ASA) as well as duodenal ulcers induced by dulcerozine. In particular [Ala5]NKA(4-10) and [Ala5,beta Ala8]NKA(4-10) possess a broad spectrum of antiulcer activity which is long lasting and stronger than the precursor NKA(4-10). The observation that the prevention of ethanol-induced gastric lesions could be reversed by pretreatment with indomethacin favors the possible involvement of prostaglandins in the observed gastroprotection by TK analogs. 相似文献
228.
Background
In recent years, several new hypotheses on phylogenetic relations among arthropods have been proposed on the basis of DNA sequences. One of the challenged hypotheses is the monophyly of hexapods. This discussion originated from analyses based on mitochondrial DNA datasets that, due to an unusual positioning of Collembola, suggested that the hexapod body plan evolved at least twice. Here, we re-evaluate the position of Collembola using ribosomal protein gene sequences. 相似文献229.
Paul H. Evangelista Sunil Kumar Thomas J. Stohlgren Catherine S. Jarnevich Alycia W. Crall John B. Norman III David T. Barnett 《Diversity & distributions》2008,14(5):808-817
Predicting suitable habitat and the potential distribution of invasive species is a high priority for resource managers and systems ecologists. Most models are designed to identify habitat characteristics that define the ecological niche of a species with little consideration to individual species' traits. We tested five commonly used modelling methods on two invasive plant species, the habitat generalist Bromus tectorum and habitat specialist Tamarix chinensis , to compare model performances, evaluate predictability, and relate results to distribution traits associated with each species. Most of the tested models performed similarly for each species; however, the generalist species proved to be more difficult to predict than the specialist species. The highest area under the receiver-operating characteristic curve values with independent validation data sets of B. tectorum and T. chinensis was 0.503 and 0.885, respectively. Similarly, a confusion matrix for B. tectorum had the highest overall accuracy of 55%, while the overall accuracy for T. chinensis was 85%. Models for the generalist species had varying performances, poor evaluations, and inconsistent results. This may be a result of a generalist's capability to persist in a wide range of environmental conditions that are not easily defined by the data, independent variables or model design. Models for the specialist species had consistently strong performances, high evaluations, and similar results among different model applications. This is likely a consequence of the specialist's requirement for explicit environmental resources and ecological barriers that are easily defined by predictive models. Although defining new invaders as generalist or specialist species can be challenging, model performances and evaluations may provide valuable information on a species' potential invasiveness. 相似文献
230.
De Moliner KL Evangelista de Duffard AM Soto E Duffard R Adamo AM 《Neurochemical research》2002,27(11):1439-1446
2,4-Dichlorophenoxyacetic acid (2,4-D) and derivatives are herbicides widely used in Argentina and other parts of the world. Exposure to 2,4-D, its ester and salt formulations, have been associated with a range of adverse health effects in humans and different animal species, from embryotoxicity and teratogenicity to neurotoxicity. In this work, we demonstrate that after 24 hs of treatment with 1 and 2 mM 2,4-D there is an induction of apoptosis in cerebellar granule cells (CGC) in culture. However, with 2 mM 2,4-D one population of CGC developed features of apoptosis while another appeared to die by necrosis. This process is associated with an increase in caspase-3 activity after 12 hs of treatment with the herbicide, which is preceded by cytochrome c release from the mitochondria. Treatment of CGC with 2,4-D appears to induce apoptosis by a direct effect on mitochondria producing cytochrome c release and consequently activation of caspase-3, being mitochondrial damage sufficient for triggering the events that may cause apoptosis. 相似文献