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91.
Interleukin-1 receptor antagonist (IL-1ra) gene polymorphisms in 83 human immunodeficiency virus (HIV)-seropositive women were evaluated. Fourteen of the subjects (16.9%) were homozygous for IL-1ra allele 2 (IL-1RN*2). These women had a lower median level of HIV RNA than did women homozygous for allele 1 (IL-1RN*1) (P = 0.01) or heterozygous for both alleles (P = 0.04). Among 46 subjects not receiving antiretroviral treatment, HIV levels were also reduced in IL-1RN*2 homozygous individuals (P < 0.05). There was no relation between IL-1ra alleles and CD4 levels.  相似文献   
92.
Genetic polymorphism of acid phosphatases wasinvestigated in 11 populations of the two European Alosaspecies using isoelectric focusing after sampletreatment with neuraminidase. Two distinct loci, ACP1 and ACP2, were detected being ACP2 polymorphic.The observed genetic diversity between the species atthe ACP2 locus supports other studies which indicatethat A. alosa is the less polymorphic species of the two. This locus shows a higher geographicthan interspecific pattern of differentiation and theACP*2 allele is essentially confined to theMediterranean.  相似文献   
93.
Enrichment culture experiments employing soil and water samples obtained from petroleum-contaminated environments succeeded in the isolation of a pure culture possessing the ability to utilize quinoline as a sole nitrogen source but did not utilize quinoline as a carbon source. This culture was identified as Pseudomonas ayucida based on a partial 16S rRNA gene sequence, and the strain was given the designation IGTN9m. Examination of metabolites using thin-layer chromatography and gas chromatography-mass spectrometry suggests that P. ayucida IGTN9m converts quinoline to 2-quinolinone and subsequently to 8-hydroxycoumarin. Resting cells of P. ayucida IGTN9m were shown to be capable of selectively removing about 68% of quinoline from shale oil in a 16-h treatment time. These results suggest that P. ayucida IGTN9m may be useful in petroleum biorefining for the selective removal of organically bound nitrogen from petroleum.  相似文献   
94.
AIMS: Agaricus brasiliensis (previously named Agaricus blazei ss. Heinem), also known as the sun mushroom is native of Southeast Brazil, and is widely consumed, mainly in the form of tea, due to its nutritional and pharmacological properties. In this study, we tested aqueous (AqE) and ethanol (EtOHE) extracts and an isolated polysaccharide (PLS) from the fruiting body of A. brasiliensis, for antiviral activity against poliovirus type 1 in HEp-2 cells. METHODS AND RESULTS: The evaluation of the time of addition by plaque assay showed that when AqE, PLS and EtOHE were added, just after the virus inoculation (time 0 h), there was a concentration-dependent reduction in the number of plaques up to 50%, 67% and 88%, respectively, with a selectivity index (SI) of 5.4, 9.9 and 12.3, respectively. CONCLUSIONS: The test substances showed antiviral activity and were more effective when added during the poliovirus infection. As they had little effect on reducing viral adsorption and did not show any virucidal effect, we suggest that they act at the initial stage of the replication of poliovirus. SIGNIFICANCE AND IMPACT OF THE STUDY: These results corroborate that basidiomycetes can be a rich source of potential antiviral compounds.  相似文献   
95.
During 2004, four experiments were carried out, one each season, in order to determine the species composition and seasonal dynamics of Calliphoridae in a rural area of Córdoba (Argentina). Two pigs (Sus scrofa L.), weighing approximately 8 Kg each, were used in each experiment. They were killed with a blow to the head and immediately placed in a variant of the Schoenly et al. (1991) trap. One pig was exposed in the shade and the other one under direct sunlight. The insect fauna was collected daily during the four first weeks and every two or three days thereafter. A total of 16.609 adults of Calliphoridae were collected, and later on identified as one of the following seven species: Chrysomya albiceps (Wiedemann), Chrysomya megacephala (Fabricius), Phaenicia sericata (Meigen), Phaenicia eximia (Wiedemann), Cochliomyia macellaria (Fabricius), Sarconesia chlorogaster (Wiedemann) and Calliphora vicina Robineau-Desvoidy. C. albiceps was the dominant species in summer, autumn and spring, being replaced in winter by C. vicina, S. chlorogaster and P. sericata. The analysis of the seasonal distribution of the species revealed that the greater incidences are in the months of summer, autumn and spring.  相似文献   
96.
Epigenetics refers to heritable changes in gene expression that are independent of alterations in DNA sequence. It is now accepted that disruption of epigenetic mechanisms plays a key role in the pathogenesis of cancer: culminating in altered gene function and malignant cellular transformation. DNA methylation and histone modifications are the most widely studied changes but non-coding RNAs such as miRNAs are also considered part of the epigenetic machinery. The insulin-like growth factor (IGF) axis is composed of two ligands, IGF-I and –II, their receptors and six high affinity IGF binding proteins (IGFBPs). The IGF axis plays a key role in cancer development and progression. As IGFBP genes have consistently been identified among the most common to be aberrantly altered in tumours, this review will focus on epigenetic regulation of IGFBP-3 in cancer for which the majority of evidence has been obtained.  相似文献   
97.
Here, we aimed to discriminate between the spectral profiles of spent culture media after oocyte in vitro maturation (IVM) and culture (IVC) from goats of different ages subjected to repeated hormonal treatments. The profiles were discriminated using near infrared (NIR) spectroscopy combined with multivariate methods. A total of 19 goats (young = 10; old = 9) were subjected to serial hormonal stimulation (HS) with gonadotropins. Cumulus oophorus complexes (COCs) were collected using laparoscopic ovum pick-up (LOPU) and subjected to IVM and parthenogenetic activation. The initial embryos were subjected to IVC. Spent culture media were collected after oocyte IVM and on day 2 of IVC and analyzed using NIR spectroscopy. NIR spectral data were interpreted through chemometric methods, such as principle component analysis (PCA) and partial least square discriminant analysis (PLS-DA). The results of PCA analysis clearly showed a separation in the spectral profiles between the experimental groups (HS sessions; young and old animals) both after IVM and IVC. Overall, the main absorption bands were attributed to the C-H group second overtone, first overtone of O-H and N-H, and C-H combinations and may serve as molecular markers. On the other hand, the spectral data obtained using PLS-DA models provided a better classification of the groups. The results showed the possibility of discriminating young and old groups as well as the three HS sessions with high specificity, sensitivity, and accuracy using NIR spectra. Thus, the culture medium analysis using NIR spectroscopy combined with multivariate methods indicated the dissimilarities between the groups and provided an insight into the in vitro development of goat oocytes. This technique serves as an efficient, objective, rapid, and non-invasive method to discriminate spectral profiles.  相似文献   
98.
Actinomycetes were isolated from an acidic Brazilian soil under cerrado (savanna) vegetation, previously amended with chitin. The efficiency of two isolation techniques, the conventional dilution plate and the dispersion and differential centrifugation (DDC) procedures, were compared and a mathematical computer analysis of the results was made. The DDC technique gave counts about nine times greater than the conventional one. Analysis of the derivative curves suggested the presence of two distinct groups of actinomycetes on the isolation plates, one able to induce chitinolytic enzymes during amendment and the other whose initial activity was delayed. Major differences in results with different isolation procedures suggest a more subtle ecological role for these microbes in terms of their location in the soil environment.  相似文献   
99.
This study examined the effect of glycerin supply strategies in different short-term protocols on follicular dynamics and ovulatory rate in Morada Nova sheep. Eighteen Morada Nova ewes with body condition > 2.9 had their estrus and follicular waves synchronized using three injections of prostaglandin analogue at seven-day intervals. All animals received the same diet during 21 days, which consisted of a total mixed ration (TMR) based on chopped elephant grass and concentrate twice daily. In the control group (n=9), ewes were fed the TMR diet. In the other four groups, ewes received 150 mL of glycerol daily, supplied as an oral drench or mixed in the TMR during three or seven days prior to the application of the third PGF2 alfa analogue. These groups were named as follows: Drench3d (n=10), Drench7d (n=8), TMR3d (n=9) and TMR7d (n=9). Follicle dynamics were monitored by ultrasonography, and plasma glucose and glutathione peroxidase levels were measured at the third prostaglandin administration. Six days after the final PGF2 alfa analogue dose, ovulatory rate was measured by laparoscopy. Glucose was higher (P< 0.001) in the glycerin-treated groups than in control group (83.7 ± 1.7 vs. 68.4 ± 4.5 mg. dL-1; P < 0.001). Ewes in the TMR3d, Drench7d and TMR7d groups had a greater (P < 0.001) number of large follicles (≥ 3 < 5 mm), and the presence of follicles larger than 5 mm was observed. In the same groups, at the third PGF2 alfa analogue dose, a greater (P < 0.001) number of growing follicles (> 3 mm) and a larger size of the largest follicle (P < 0.001) were also recorded. Ovulation rate was 30% higher in the groups that received glycerin for seven days (1.6 ± 0.1 53 vs. 1.1 ± 0.1; P < 0.05), and they also exhibited a 38% reduction in glutathione peroxidase. Thus, the use of glycerin in Morada Nova sheep as a source of energy in short-term supplementation for increase ovulation rate is an efficient strategy when provided for seven days, either orally or in the feed.  相似文献   
100.
Neurochemical Research - Mitochondrial respiratory chain complexes enzymatic (MRCCE) activities were successfully evaluated in frozen brain samples. Epilepsy surgery offers an ethical opportunity...  相似文献   
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