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101.
The atmosphere of Málaga was sampled from 1992 to 1995 for the pollen of Olea europaea L., one of the most common airborne allergens in the Mediterranean area. A Burkard seven-day-recording trap showed that the pollen of this species is principally detected during spring with the highest concentrations occurring in May. During the main pollination period, the 24 hour intradiurnal variation pattern showed a high degree of homogeneity with no noteworthy peaks. The correlations between the pollen concentrations recorded and the different meteorological parameters show that temperature, sunshine hours and wind direction are those most closely correlated with variations in the daily pollen count. 相似文献
102.
S. Docampo M. M. Trigo M. Recio M. Melgar J. García-Sánchez M. C. Calderón-Ezquerro B. Cabezudo 《Aerobiologia》2010,26(2):89-98
The cave of Nerja, which is visited annually by more than half a million people, is a karstic cavity situated in the east
part of the province of Malaga (southern Spain), with internal conditions of humidity and temperature that make it a space
highly conducive to the development of fungus. Fungal spores are of great interest in aerobiology and allergy due to their
high incidence in both outdoor and indoor environments and their widely recognized ability to cause respiratory diseases and
other pathologies. In this work, we focus on the seasonal and intradiurnal study of the Aspergillus/Penicillium spore type (conidia), which is especially abundant in the atmosphere inside the cave of Nerja. This study was carried out
over an uninterrupted period of 4 years (2002–2005) with the aid of a Hirst-type volumetric pollen trap (Lanzoni VPPS 2000)
situated in one of the halls of the cave. The results show that the spores of Aspergillus/Penicillium type represent 48.6% of the annual spore index, June, July and August being the months with the highest rates of these spores,
with an average incidence for the 4 years of 11, 63 and 15% of the annual total, respectively. However, the most interesting
observation was the sudden increase in the concentration of these spores that occurred during 1 day of the year, when levels
might reach nearly 300,000 spores/m3 of air as daily mean. Finally, it was concluded that these peaks were due to human activities carried out inside the cave,
coinciding with celebration of the annual festival of dance and music. On the other hand, the intradiurnal study showed that
the highest concentrations are reached between 1200 and 1400 hours. Although there are no standard indices related to the
risk of exposure to spore concentrations, we think that the values obtained were high enough to be considered as a potential
risk factor capable of producing harmful effects on human health. We therefore recommend taking the necessary measures to
prevent such high increases in the spore levels inside the cave. 相似文献
103.
Alfonso De la Mora Francisco Suárez-Güemes Francisco Trigo Patricia Gorocica Carlos Solórzano Marie-Christine Slomianny Concepción Agundis M. Ali Pereyra Edgar Zenteno 《Biochimica et Biophysica Acta (BBA)/General Subjects》2007
The GlcNAc-specific adhesin from Mannheimia haemolytica (MhA) has been shown to participate in pathogenicity of mannheimiosis due to its capacity to adhere to tracheal epithelial cells and activate the oxidative burst of bovine neutrophils. In this work, we purified the MhA receptor from bovine neutrophils (MhAr) by affinity chromatography on MhA-Sepharose. The MhAr, which corresponded to approximately 2% of the protein from cell lysate, is a glycoprotein mainly composed of Glu, Ala, Ser, Gly, and Asp, without cysteine. The glycan portion, which corresponds to 20% by weight, is composed of GalNAc, GlcNAc, Man, Gal, and NeuAc. The receptor is a 165-kDa glycoprotein, as determined by molecular sieve chromatography under native conditions; SDS-PAGE analysis shows a heterodimer of 83 and 80 kDa subunits. This work suggests that the GlcNAc-containing receptor plays a relevant role by activating bovine neutrophils through non-opsonic mechanisms. 相似文献
104.
Almudena Sánchez‐Villegas Adriano M. Pimenta Juan J. Beunza Francisco Guillen‐Grima Estefanía Toledo Miguel A. Martinez‐Gonzalez 《Obesity (Silver Spring, Md.)》2010,18(7):1443-1448
This study included 11,825 participants of a Spanish dynamic prospective cohort based on former students from University of Navarra, registered professionals from some Spanish provinces, and university graduates from other associations, followed‐up for 6.1 years. We aimed to assess the association between childhood or young adult overweight/obesity and the risk of depression. Participants were asked to select which of nine figures most closely represented their body shape at ages 5 and 20 years. Childhood and young adult overweight/obesity was defined as those cases in which participants reported body shape corresponding to the figures 6–9 (more obese categories) at age 5 or 20, respectively. A subject was classified as incident case of depression if he/she was initially free of depression and reported physician‐made diagnosis of depression and/or the use of antidepressant medication in at least one of biannual follow‐up questionnaires. The association between childhood and young adult overweight/obesity and incidence of depression was estimated by multiple‐adjusted hazard ratio (HR) and its 95% confidence interval (95% CI). Overweight/obesity at age 5 years predicted an increased risk for adult depression (HR = 1.50, 95% CI = 1.06–2.12), and a stronger association was observed at age 20 years ((HR = 2.22, 95% CI = 1.22–4.08), (subjects younger than 30 years at recruitment were excluded from this last analysis)). Childhood or young adult overweight/obesity was associated with elevated risk of adult depression. These results, if causal and confirmed in other prospective studies, support treating childhood and young adult overweight/obesity as part of comprehensive adult depression prevention efforts. 相似文献
105.
Nikolay Vassilev Maria Vassileva Rosario Azcon Almudena Medina 《Biotechnology letters》2001,23(2):149-151
Four times higher nodule number was observed when Glomus deserticola (an arbuscular mycorrhizal fungus) was introduced into a soil-plant system as compared to the control inoculated only with Rhizobium trifoli. This symbiotic parameter was further enhanced by Yarowia lipolytica together with an increase in root mycorrhizal infection of about 14%. Soil inoculation with co-encapsulated R. trifoli and Y. lipolytica provoked a 10-fold increase in root nodulation and led to 55% mycorrhization of the test plant. 相似文献
106.
Therapeutic concentrations of varenicline in the presence of nicotine increase action potential firing in human adrenal chromaffin cells 下载免费PDF全文
107.
Lysine has long been recognized as an essential amino acid for humans and the lack or low supply of this compound in the diet may lead to mental and physical handicaps. Since lysine is severely restricted in cereals, the most important staple food in the world, the understanding of its biological roles must be a major concern. Here we show that lysine is an important precursor for de novo synthesis of glutamate, the most significant excitatory neurotransmitter in the mammalian central nervous system. We also show that the synthesis of glutamate from lysine, which is carried out by the saccharopine pathway, is likely to take place in neurons. 相似文献
108.
109.
New records are reported for a Hemipteran (Largus rufipennis) and a Coleopteran (Chauliognathus fallax) feeding on Senecio brasiliensis (Asteraceae) and sequestering pyrrolizidine alkaloids (PAs). Both insects are warningly colored and rejected by predators. 相似文献
110.
We purified an adhesin from Pasteurella. haemolytica by affinity chromatography using glutaraldehyde treated rabbit erythrocytes stroma. The adhesin is a protein of 68 kDa, as determined by SDS-PAGE, and the most abundant amino acids constituting this protein were Gly, Ser, Glx, and Ala, and low concentrations of Cys, Met, and Tyr residues were also found. The N-terminal sequence of the adhesin is ANEVNVYIYKQPYLI. No carbohydrate residues were detected. The adhesin agglutinated rabbit erythrocytes but when the latter were desialylated or pronase treated the agglutinating activity was abolished. The agglutinating activity of the adhesin was inhibited with N-acetyl-D-glucosamine (GlcNAc), and in a lesser degree with N-acetyl-neuraminic acid (NeuAc). GalNAc, N-glycolyl-neuraminic acid, N-deacetylated GlcNAc, or neutral sugars do not modify the activity of the adhesin. The equatorial -OH on C4 and the NH-acetylated group on C2 from GlcNAc, as well as the 4-OH and NH-acetylated group on C5 from NeuAc seem to be responsible for the interaction with the adhesin. The protein is divalent cation-dependent and thermolabile. As for the agglutinating activity, the adhesion of P.haemolytica to tracheal cell-cultures was inhibited by GlcNAc, NeuAc or the purified adhesin, strongly suggesting that the P.haemolytica adhesin plays an important role in infection. 相似文献