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1.
PGRP-S (Tag7) is an innate immunity protein involved in the antimicrobial defense systems, both in insects and in mammals. We have previously shown that Tag7 specifically interacts with several proteins, including Hsp70 and the calcium binding protein S100A4 (Mts1), providing a number of novel cellular functions. Here we show that Tag7–Mts1 complex causes chemotactic migration of lymphocytes, with NK cells being a preferred target. Cells of either innate immunity (neutrophils and monocytes) or acquired immunity (CD4+ and CD8+ lymphocytes) can produce this complex, which confirms the close connection between components of the 2 branches of immune response.  相似文献   
2.
34Fusarium graminearum Schw isolates produced 4-deoxynivalenol to form significant amounts of 4, 7 — dideoxynivalenol and lesser amounts of 4 — deoxynivalenol monoacetates on grain substratesin vitro. This is the first report on the capability a large group of naturally occurring isolates to produce 4,7-dideoxynivalenol. The average levels of 4,7-dideoxynivalenol on rice, corn, barley, and wheat as a substrate were respectively 26.8, 14.0, 12.8, and 10.5% of the level of 4-deoxynivalenol. 4, 7 — dideoxynivalenol was present in all examined naturally contaminated wheat kernel samples at levels of 1.7 to 7.9% of the level of 4-deoxynivalenol. These findings suggest that more attention should be given to the occurrence of 4,7-dideoxynivalenol in cereals.  相似文献   
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Lukina  A. P.  Avakyan  M. R.  Danilova  E. V.  Karnachuk  O. V. 《Microbiology》2020,89(6):789-792
Microbiology - Deep biosphere is an prolific source of novel prokaryotes. A phylogenetically distant lineage of Firmicutes was reported in 2019 as a new genus Thermoanaerosсeptrum. Ecology of...  相似文献   
5.
Objectives Somatoform disorders are common in international primary care settings, but have been little studied in the developing world. The objective of this study was to determine the prevalence of severe undifferentiated somatoform disorder, and its relationship to depression and anxiety, among patients attending walk-in clinics in Trinidad.Methods The study participants, who were all aged 18 years or older and attending walk-in clinics at 16 randomly selected health centres, were surveyed between May and August 2007 using the PRIME-MD questionnaire.Results There were 594 participants (the response rate was 92%), of whom 72.7% were female. Their ages ranged from 18 to 93 years, and 54.5% were over 50 years of age. In total, 37.2% were married and 25.9% were single. Indo-Trinidadians represented 43.1% and Afro-Trinidadians represented 36% of the study sample; 56.5% of the participants reported that their income was less than US$ 400 per month, and 65.7% were unemployed. At walk-in clinics in Trinidad, the estimated prevalence of severe undifferentiated somatoform disorder was 10.3% (95% CI: 7.86–12.74), that of hypochondriasis was 28.5% (95% CI: 24.9–32.1), and that of body dysmorphic disorder was 15.8% (95% CI: 11.9–18.7). Severe undifferentiated somatoform disorder was statistically significantly associated with gender and ethnicity but not with age, level of education, employment status or income. Chi-square testing found significant associations between the presence of severe undifferentiated somatoform disorder and both depression and anxiety (P < 0.05), between hypochondriasis and both anxiety and depression (P < 0.05), and between body dysmorphic disorder and depression (P < 0.05) but not anxiety. Regression analysis suggested that the demographic features that predicted severe undifferentiated somatoform disorder were being female or Indo-Trinidadian.Conclusions Walk-in clinics in Trinidad that serve older patients on a lower income have a high proportion of patients with somatoform disorders as measured by the PRIME-MD scale. These patients exhibit many features of anxiety and depression. These findings have implications for medical training and service delivery.  相似文献   
6.
Lukina NI  Soĭdla TR 《Tsitologiia》2002,44(6):585-591
Using our own original computer program, we analysed more than 10 millions b.p. of the complete nucleotide sequence in the human chromosome 21. A graphic catalogue of largest stereospecific anomalies of this sequence is presented. Clusters of different stereospecific anomalies, showing presumably areas of cooperative binding of different regulatory and structural proteins to DNA have been revealed. Most of the large stereospecific anomalies are situated in introns, being often accompanied by regions devoid of some specific dinucleotides.  相似文献   
7.

Background  

Phylogenetic hypotheses of higher-level relationships in the order Charadriiformes based on morphological data, partly disagree with those based on DNA-DNA hybridisation data. So far, these relationships have not been tested by analysis of DNA sequence data. Herein we utilize 1692 bp of aligned, nuclear DNA sequences obtained from 23 charadriiform species, representing 15 families. We also test earlier suggestions that bustards and sandgrouses may be nested with the charadriiforms. The data is analysed with methods based on the parsimony and maximum-likelihood criteria.  相似文献   
8.
In late summer 2004 stem discs were collected from about 40 juniper trees (Juniperus Siberica Burgsd) growing at the remote central part of Kola Peninsula behind the polar circle at the northern timberline. Up to now these juniper trees are oldest ones found at Kola Peninsula. Data processing was difficult due to extremely small tree rings as well as the occurrence of missing and false rings. However, finally it was possible to build up a 676-year long chronology and retrieve information on the past climatic variations at Kola Peninsula that could partly be linked to extraterrestrial factors such as changes in solar activity and galactic cosmic ray activity. It was obtained that:
(1) There is a rather good agreement between long-term climatic variation in Europe and at Kola Peninsula.

(2) The minima of solar activity Sporer (1416–1534 AD), Maunder (1645–1715 AD) and Dalton (1801–1816 AD) were accompanied by temperature decreases. Cooling during the end of the Wolf minimum (until 1350) is reflected in the juniper tree-ring series from Kola Peninsula whereas it is not reflected in the European temperature reconstructions.

(3) Some recent decreases in solar activity around 1900 and 1960 are linked to phases of reduced growth in juniper.

(4) The juniper chronologies from Kola Peninsula do not indicate a temperature rise at the end of the XX century.

(5) MTM spectral and wavelet analysis of juniper tree-ring records showed:

(a) more pronounced 22- and 80–100-year periodicities;

(b) the main cycle of solar activity, the 11-year Schwabe cycle, was not present;

(c) 20–22-year periodicity was not significant throughout the entire ca.700-year period, but during certain time intervals: 1328–1550, 1710–1800, 1985 to present.

Keywords: Juniperus Siberica Burgsd; 676-year chronology; Kola Peninsula; Solar cycles  相似文献   

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Natural and anthropogenically induced seasonal variations in the abundance and biomass of various groups of microorganisms in the Al–Fe–humus podzols of boreal spruce forests were analyzed. The fungal biomass in these soils was found to be considerably higher than the bacterial biomass. The microbial population was mainly concentrated in a thin surface layer (10–15 cm in thickness), which included the forest litter and the upper mineral root-inhabited soil horizon and greatly differed from other soil horizons in morphology and other properties. This layer was found to be optimal with respect to hydrothermal and nutritional conditions and is characterized by profound seasonal variations in the abundance and biomass of microbiota. The high acidity, typical of the Al–Fe–humus podzols, resulted from the metabolism of their microbial communities. In the polluted podzols, the population of prokaryotes increased and that of eukaryotes decreased.  相似文献   
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