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1.
Marvin J. Allison Guillermo Focacci Calogero Santoro 《American journal of physical anthropology》1982,59(3):299-304
Burials and mummies of dogs from the Arica, Chile, area are described. It is concluded that these dogs were brought to this area 2500 years ago by shepherds from the highlands and are still present, relatively unchanged. 相似文献
2.
Biochemical and phenotypical correction of an envelope mutant of Salmonella typhimurium 总被引:1,自引:0,他引:1
R A Pizarro G O Boselli L V Orce 《Archives internationales de physiologie et de biochimie》1984,92(5):333-337
Salmonella typhimurium DA 361 bears an env D1 mutation with the following abnormal phenotypical and biochemical characteristics: a) it autolyses at stationary phase in nutrient broth; b) it grows in chains of short rods; c) it is a poor maltose fermenter and d) it has a diphosphatidylglycerol (DPG) content twice as high than its isogenic non-lytic pair DA 362 (env D+) and LT2, of which both are derivatives. Growth of DA 361 in the presence of 400 mM ethanol leads on a 50% decrease of DPG level, thereby equalling its PG/DPG ratio with those of the control strain. Consequently, a correction on the other phenotypical and biochemical anomalies are induced since the DA 361 strain decreases its autolytic activity, ferments normally maltose and appear as rods undifferentiated from DA 362. 相似文献
3.
We have compared the species richness of medicinal plants and the differential patterns of use amongst settlements in the
Andean communities of Northwest Argentina which have differing levels of isolation. About 259 ethnoespecies, belonging to
74 plant families, were included, representing between 70 and 80% of the total estimate. The results indicate that Coronopus didymus is the most relevant and important species. The method of use of medicinal plants and the ailments treated by rural doctors compared to those of the layperson is different. Native and exotic plants are used differently according to the body system
treated. There are some relationships between internal and external use and body systems and recipes. The greater medicinal
species richness found in the less isolated locations is due to external enriching cultural influences. 相似文献
4.
5.
Javier J Gonzalez-Rosa Manuel Vazquez-Marrufo Encarnacion Vaquero Pablo Duque Monica Borges Carlos M Gomez-Gonzalez Guillermo Izquierdo 《BMC neurology》2011,11(1):64-19
Background
Event-related potentials (ERPs) may be used as a highly sensitive way of detecting subtle degrees of cognitive dysfunction. On the other hand, impairment of cognitive skills is increasingly recognised as a hallmark of patients suffering from multiple sclerosis (MS). We sought to determine the psychophysiological pattern of information processing among MS patients with the relapsing-remitting form of the disease and low physical disability considered as two subtypes: 'typical relapsing-remitting' (RRMS) and 'benign MS' (BMS). Furthermore, we subjected our data to a cluster analysis to determine whether MS patients and healthy controls could be differentiated in terms of their psychophysiological profile. 相似文献6.
Salomé C. Vilchez Larrea Mariana Schlesinger María L. Kevorkian Mirtha M. Flawiá Guillermo D. Alonso Silvia H. Fernández Villamil 《PloS one》2013,8(6)
Trypanosoma cruzi, etiological agent of Chagas’ disease, has a complex life cycle which involves the invasion of mammalian host cells, differentiation and intracellular replication. Here we report the first insights into the biological role of a poly(ADP-ribose) glycohydrolase in a trypanosomatid (TcPARG). In silico analysis of the TcPARG gene pointed out the conservation of key residues involved in the catalytic process and, by Western blot, we demonstrated that it is expressed in a life stage-dependant manner. Indirect immunofluorescence assays and electron microscopy using an anti-TcPARG antibody showed that this enzyme is localized in the nucleus independently of the presence of DNA damage or cell cycle stage. The addition of poly(ADP-ribose) glycohydrolase inhibitors ADP-HPD (adenosine diphosphate (hydroxymethyl) pyrrolidinediol) or DEA (6,9-diamino-2-ethoxyacridine lactate monohydrate) to the culture media, both at a 1 µM concentration, reduced in vitro epimastigote growth by 35% and 37% respectively, when compared to control cultures. We also showed that ADP-HPD 1 µM can lead to an alteration in the progression of the cell cycle in hydroxyurea synchronized cultures of T. cruzi epimastigotes. Outstandingly, here we demonstrate that the lack of poly(ADP-ribose) glycohydrolase activity in Vero and A549 host cells, achieved by chemical inhibition or iRNA, produces the reduction of the percentage of infected cells as well as the number of amastigotes per cell and trypomastigotes released, leading to a nearly complete abrogation of the infection process. We conclude that both, T. cruzi and the host, poly(ADP-ribose) glycohydrolase activities are important players in the life cycle of Trypanosoma cruzi, emerging as a promising therapeutic target for the treatment of Chagas’ disease. 相似文献
7.
8.
A rapid extraction method for screening aflatoxin producing potential ofAspergillus flavus group isolates is described. The method is performed using a moist wheat medium with ca. five infected grains extracted with 2 mL of chloroform, and using thin layer chromatography. This method was proved with 95A. flavus isolates from animal feeds. 相似文献
9.
Guillermo Ortega Diego A. Golombek Dino Otero Lilia Romanelli Daniel P. Cardinali 《Chronobiology international》1992,9(2):137-147
The two-oscillator model of human circadian rhythmicity was analyzed when a zeitgeber relative intensity of 1, 0.5, or 0.1 was introduced into the equations. Fourier analysis was compared with dynamic analysis such as attractor reconstruction or Liapunov exponent calculation. After a 50 or 90% reduction in zeitgeber intensity, the dynamics of the system became equivalent and differed significantly from those of a system with maximal zeitgeber intensity. When 10% aleatory noise was added to the data, the analysis was still applicable, and the results obtained were essentially the same as in the absence of noise. Dynamic analysis could thus provide a distinct classification for periodic data, based on the type of analysis. 相似文献
10.
The total and relative energies, bond order matrices and localized MOs for the eight possible tautomers of hypoxanthine (HYP) have been calculated, with full geometry optimization, using both AM1 and MNDO methods. The AM1 relative energies show that HYP(9,1), HYP(7,1) and HYP (9,10) are the predominant species at room temperature, the two former being in larger concentration that the latter. The calculated IR spectra for these species agree well with the reported spectrum in an isolated matrix, which has been interpreted in terms of the presence of these three tautomeric forms. The MNDO method does not predict the right order, and the more stable tautomer would be HYP(9,10). The calculated structure for the HYP(9,1) species shows that the molecule is essentially planar. The bond distances compare well with those of hypoxanthine hydrochloride and guanine and also correlate well with the calculated bond orders. The proton affinities for the three more stable tautomers have also been calculated. For HYP(9,1) the prefered site of protonation is N7, whereas for HYP(7,1) the protonation occurs rather at N9. These results agree well with15N and13C NMR studies in DMSO. 相似文献