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排序方式: 共有226条查询结果,搜索用时 15 毫秒
191.
Maria Marcano Sonia Morales Maria Theresa Hoyer Brigitte Courtois Ange Marie Risterucci Olivier Fouet Tatiana Pugh Emile Cros Ventura Gonzalez Manuel Dagert Claire Lanaud 《Tree Genetics & Genomes》2009,5(2):329-337
The selection of productive varieties of modern Criollo cocoa, showing fine aromatic qualities in their beans, is of major
interest for some producing countries, such as Venezuela. Cultivated populations of Modern Criollo or Trinitario varieties
may be suitable for admixture mapping analysis, as large blocks of alleles derived from two identified divergent ancestors,
recently admixed, are still preserved, after a few generations of recombination, similar to experimental mapping progenies.
Two hundred and fifty-seven individuals from a cultivated population of Modern Criollo were selected and analysed with 92
microsatellite markers distributed along the genome. This population exhibited a wide range of variability for yield factors
and morphological features. Population structure analysis identified two main subgroups corresponding to the admixture from
the two ancestors Criollo and Forastero. Several significant associations between markers and phenotypic data (yield factors
and morphological traits) were identified by a least squares general linear model (GLM) taking into account the population
structure and the percentage of admixture of each individual. Results were compared with classical QTL analyses previously
reported for other cacao populations. Most markers associated to quantitative traits were very close to QTLs detected formerly
for the same traits. Associations were also identified between markers and several qualitative traits including the red pigmentation
observed in different organs, mainly associated to common markers in linkage group 4. 相似文献
192.
Tascini C Polidori M Flammini S Fondelli S Mencarini J Vetrano U Lambelet P Tagliaferri E Menichetti F 《The new microbiologica》2010,33(3):267-269
We describe a case of acute varicella-zoster virus (VZV) hemorrhagic meningoencephalomyelitis in an HIV-infected patient. On admission the patient's CSF was mild haemorrhagic and xanthochromic after centrifugation and he had thoracic skin blisters. VZV DNA was isolated from both the thoracic blisters and CSF. Treatment consisted of aggressive antiviral, steroid and immunoglobulin therapy, which was able to stop disease progression. The patient survived but was left blind and paretic. In conclusion, a diagnosis of CNS infection caused by VZV, based upon CSF analysis and examination of the skin for typical blisters, requires aggressive empiric antiviral therapy in order to maximise patient survival. 相似文献
193.
Ghislain Emmanuel Sopoh Yves Thierry Barogui Roch Christian Johnson Ange Dodji Dossou Michel Makoutodé Sévérin Y. Anagonou Luc Kestens Fran?oise Portaels 《PLoS neglected tropical diseases》2010,4(7)
Background
Mycobacterium ulcerans disease (Buruli ulcer) is the most widespread mycobacterial disease in the world after leprosy and tuberculosis. How M. ulcerans is introduced into the skin of humans remains unclear, but it appears that individuals living in the same environment may have different susceptibilities.Objectives
This study aims to determine whether frequent contacts with natural water sources, family relationship or the practice of consanguineous marriages are associated with the occurrence of Buruli ulcer (BU).Design
Case control study.Setting
Department of Atlantique, Benin.Subjects
BU-confirmed cases that were diagnosed and followed up at the BU detection and treatment center (CDTUB) of Allada (Department of the Atlantique, Benin) during the period from January 1st, 2006, to June 30th, 2008, with three matched controls (persons who had no signs or symptoms of active or inactive BU) for age, gender and village of residence per case.Main Outcomes Measured
Contact with natural water sources, BU history in the family and the practice of consanguineous marriages.Results
A total of 416 participants were included in this study, including 104 cases and 312 controls. BU history in the family (p<0.001), adjusted by daily contact with a natural water source (p = 0.007), was significantly associated with higher odds of having BU (OR; 95% CI = 5.5; 3.0–10.0). The practice of consanguineous marriage was not associated with the occurrence of BU (p = 0.40). Mendelian disorders could explain this finding, which may influence individual susceptibility by impairing immunity.Conclusion
This study suggests that a combination of genetic factors and behavioral risk factors may increase the susceptibility for developing BU. 相似文献194.
Vendeville S Goossens F Debreu-Fontaine MA Landry V Davioud-Charvet E Grellier P Scharpe S Sergheraert C 《Bioorganic & medicinal chemistry》2002,10(6):1719-1729
Prolyl endopeptidases (PEPs) have been found in numerous species. Inhibitors of human enzyme could correct cognitive deficits in Alzheimer patients while inhibition of Trypanosoma cruzi PEP could prevent invasion phase in Chagas disease. A structure-activity relationship study carried out in a tetrahydroisoquinoline series allowed to obtain potent competitive inhibitors superior to SUAM-1221. Besides, inhibitors expected to act according to an irreversible mechanism revealed to be superior to JPT-4819, for applications linked to human enzyme inhibition. 相似文献
195.
196.
Crissey S Ange K Slifka K Bowen P Stacewicz-Sapuntzakis M Langman C Sadler W Ward A 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2001,128(1):155-165
Nutritional status for six captive canid species (n=34) and four captive ursid species (n=18) were analyzed. The species analyzed included: African wild dog (Lycaon pictus), arctic fox (Alopex lagopus), gray wolf (Canis lupus), maned wolf (Chrysocyon brachyurus), Mexican wolf (Canis lupus baleiyi), red wolf (Canis rufus), brown bear (Ursus arctos), polar bear (Ursus maritimus), spectacled bear (Tremarctos ornatus), and sun bear (Ursus malayanus). Diet information was collected for these animals from each participating zoo (Brookfield Zoo, Fort Worth Zoo, Lincoln Park Zoological Gardens, and North Carolina Zoological Park). The nutritional composition of the diet for each species at each institution met probable dietary requirements. Blood samples were collected from each animal and analyzed for vitamin D metabolites 25(OH)D and 1,25(OH)(2)D, vitamin A (retinol, retinyl stearate, retinyl palmitate), vitamin E (alpha-tocopherol and gamma-tocopherol) and selected carotenoids. Family differences were found for 25(OH)D, retinol, retinyl stearate, retinyl palmitate and gamma-tocopherol. Species differences were found for all detectable measurements. Carotenoids were not detected in any species. The large number of animals contributing to these data, provides a substantial base for comparing the nutritional status of healthy animals and the differences among them. 相似文献
197.
The effect of alkaline earth cations and of ionic strength on the dissociation of earthworm hemoglobin at alkaline pH 总被引:1,自引:0,他引:1
G Polidori M G Mainwaring S N Vinogradov 《Comparative biochemistry and physiology. A, Comparative physiology》1988,89(4):541-545
1. The effect of alkaline earth cations on the dissociation of the extracellular hemoglobin of Lumbricus terrestris and the effect of ionic strength on the dissociation of the hemoglobins of L. terrestris and Tubifex tubifex at concentrations of ca 2.5 mg/ml, over the pH range 9.0-10.5 was investigated using ultracentrifugation to separate the dissociated from the undissociated molecules. 2. Mg(II), Ca(II) and Sr(II) at concentrations of up to 0.2 M, decreased the dissociation of Lumbricus oxyhemoglobin from 70% at pH 9.0 and 100% at pH 9.5 and higher, to 20-30% at 0.05 M. The three cations were equally effective in decreasing the extent of dissociation of L. terrestris oxyhemoglobin over the pH range 9.0-10.5, with a K1/2 of ca 10 mM. 3. The dissociation of L. terrestris oxyhemoglobin over the pH range 9.0-10.5 was decreased only to 50-60% in the presence of up to 0.5 M NaCl or KCl; there was no further decrease in dissociation at concentrations of the two salts up to 1.5 M. 4. The dissociation of T. tubifex oxyhemoglobin over the pH range 9.0-10.0 was decreased from 100% to ca 40-50% in the presence of 0.5 M NaCl or KCl with little or no change at higher concentrations. At pH 10.5 and 11.0 the decrease in dissociation was more gradual, reaching ca 50% at 1.5 M NaCl. 相似文献
198.
Modification of leukocytic function has been reported in only a few human parasitic diseases. In this study we evaluated the effects of the sera from patients infected with Trichinella on chemotactic and phagocytic responses in leukocytes. Leukocyte chemotaxis was tested by the agarose method and phagocytosis by the technique of Yamamura, modified for Saccharomyces cerevisiae. Sera were acquired from patients during a trichinellosis outbreak that occurred in northern Italy in 1986. The parasite was isolated from 1 patient and isoenzymatically typed as Trichinella sp. 3, a new taxon, previously considered Trichinella nelsoni. The results indicated that sera from Trichinella-infected humans inhibited both chemotaxis and phagocytic responses in leukocytes. These findings suggest the existence of serum factor(s) in trichinellosis patients that modify host leukocytic functions. The source and nature of active serum components and the mechanism by which they modulate leukocyte function remain to be clarified. 相似文献
199.
D Agostini E Polidori F Palma P Ceccaroli R Saltarelli D Tonelli V Stocchi 《Fungal genetics and biology : FG & B》2001,33(1):15-23
Recent biochemical investigations of Tuber borchii Vittad. mycelium have demonstrated the presence of three distinct forms of hexokinase (HK(M1), HK(M2), and HKM3). In the investigation described here, a gene coding for hexokinase (hxk-1) from T. borchii was isolated and characterized. The hxk-1 gene is characterized by an ORF of 1494 nucleotides and codes for a polypeptide of 497 aa. The gene was overexpressed in Escherichia coli, and the recombinant protein was kinetically characterized. The K(cat) value for fructose is in agreement with the data reported for the hexokinase of Yarrowia lipolytica, the Km for ATP is not dependent on the sugar used, and the enzyme is not inhibited by trehalose 6-phosphate or glucose 6-phosphate. The biochemical characteristics confirm that this enzyme is a hexokinase, as suggested by the Pileup results, and it corresponds to the HKM1 isoform. This work represents the first characterization of the key enzyme of the glycolytic pathway and the related gene in a Tuber species. 相似文献
200.
Sabrina Zeppa Michele Guescini Lucia Potenza Deborah Agostini Emanuela Polidori Vilberto Stocchi 《Biotechnology letters》2000,22(4):307-312
The mRNA differential display technique was used to compare mRNA populations from fruit body and mycelium of a white truffle species in the attempt to identify and clone differentially expressed genes. The differential expression of five out of 30 amplicons was confirmed. One fragment (Tbm 56) corresponded to a part of the ribosomal genes. Three cDNA fragments (Tbf 12, Tbf 20, Tbf 21) were expressed only in the fructification phase, while the other cDNA (Tbf 55) was expressed strongly in fruit body and also detectable in the mycelium. These clones correspond to part of the single-copy genes in the Tuber borchii Vittad. genome. 相似文献