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1.
The successful use of recombinant activated factor VII (rFVIIa), in treating massive, life-threatening haemoptysis in a 55-year-old male patient with chronic necrotising aspergillosis, is reported. Patient diagnosed with chronic necrotising aspergillosis three months ago was admitted to our department with massive haemoptysis. Patient was treated as outpatient with itraconazole. One day post-admission, two doses of rFVIIa (30 microg x kg(-1)) were administered and the haemoptysis was successfully resolved. Two further doses of rFVIIa (30 microg x kg(-1) were given the following day, and after that there were no more recurrences of pulmonary haemorrhage. No thromboembolic or other adverse events were observed following rFVIIa therapy. Our findings suggest that use of rFVIIa may represent a safe and effective treatment choice for patients with haemoptysis due to aspergillosis.  相似文献   
2.
Genome size, karyotype structure, heterochromatin distribution, position and number of ribosomal genes, as well as the ITS2 sequence of the internal transcribed spacer (ITS) were analysed in silver fir (Abies alba Mill.). The analysis also included characterization of the Arabidopsis-type of telomeric repeats in silver fir and in related species. The results were compared with results from other species of the Pinaceae, to evaluate phylogeny and chromosomal and molecular evolution in the Pinaceae. Integrated chromosomal data provided insights into chromosome and karyotype evolution in the Pinaceae. The evolutionary trend for GC-rich heterochromatic blocks seems to involve loss of blocks that are not associated with rDNA. Similarly, numerous large blocks of interstitial plant telomeric repeats that are typical for all analysed species of the genus Pinus were not observed in the evolutionarily younger genera, such as Abies, Picea and Larix. On the contrary, the majority of telomeric sequences in these three genera appeared confined to the chromosome ends. We confirmed the current position of Abies and Tsuga in subfamily Abietoideae and the position of Pinus in the subfamily Pinoideae based on ITS2 sequences. Pseudotsuga is placed together with Larix into the subfamily Laricoideae. We conclude that the current position of the genus Picea in the subfamily Abietoideae should be reconsidered and, possibly, the genus Picea should be reclassified as a separate subfamily, Piceoideae, as recently proposed.  相似文献   
3.
Papes S  Ladich F 《PloS one》2011,6(10):e26479

Background

Sound production and hearing sensitivity of ectothermic animals are affected by the ambient temperature. This is the first study investigating the influence of temperature on both sound production and on hearing abilities in a fish species, namely the neotropical Striped Raphael catfish Platydoras armatulus.

Methodology/Principal Findings

Doradid catfishes produce stridulation sounds by rubbing the pectoral spines in the shoulder girdle and drumming sounds by an elastic spring mechanism which vibrates the swimbladder. Eight fish were acclimated for at least three weeks to 22°, then to 30° and again to 22°C. Sounds were recorded in distress situations when fish were hand-held. The stridulation sounds became shorter at the higher temperature, whereas pulse number, maximum pulse period and sound pressure level did not change with temperature. The dominant frequency increased when the temperature was raised to 30°C and the minimum pulse period became longer when the temperature decreased again. The fundamental frequency of drumming sounds increased at the higher temperature. Using the auditory evoked potential (AEP) recording technique, the hearing thresholds were tested at six different frequencies from 0.1 to 4 kHz. The temporal resolution was determined by analyzing the minimum resolvable click period (0.3–5 ms). The hearing sensitivity was higher at the higher temperature and differences were more pronounced at higher frequencies. In general, latencies of AEPs in response to single clicks became shorter at the higher temperature, whereas temporal resolution in response to double-clicks did not change.

Conclusions/Significance

These data indicate that sound characteristics as well as hearing abilities are affected by temperatures in fishes. Constraints imposed on hearing sensitivity at different temperatures cannot be compensated even by longer acclimation periods. These changes in sound production and detection suggest that acoustic orientation and communication are affected by temperature changes in the neotropical catfish P. armatulus.  相似文献   
4.
The vomeronasal organ (VNO) of the mouse has two neuronal compartments expressing distinct families of pheromone receptors, the V1Rs and the V2Rs. We report here that two families of major histocompatibility complex (MHC) class Ib molecules, the M10 and the M1 families, show restricted expression in V2R-expressing neurons. Our data suggest that neurons expressing a given V2R specifically co-express one or a few members of the M10 family. Biochemical and immunocytochemical analysis demonstrates that in VNO sensory dendrites M10s belong to large multi-molecular complexes that include pheromone receptors and beta2-microglobulin (beta2m). In cultured cells, M10s appear to function as escort molecules in transport of V2Rs to the cell surface. Accordingly, beta2m-deficient mice exhibit mislocalization of V2Rs in the VNO and a specific defect in male-male aggressive behavior. The functional characterization of M10 highlights an unexpected role for MHC molecules in pheromone detection by mammalian VNO neurons.  相似文献   
5.
The frequency of micronuclei (MN) induced by pentachlorophenol (PCP) in haemocytes of zebra mussel, Dreissena polymorpha Pall. and great ramshorn snail, Planorbarius corneus L. was determined over a 14 days of exposure (sampling after 4, 7 and 14 days) under laboratory conditions. PCP doses for zebra mussel ranged from 10 to 150 microg/l, and for ramshorn snail from 10 to 450 microg/l. Micronuclei were detected after bisbenzimide fluorescent staining. Positive responses were observed in both species. The mean MN frequencies in treated mussels ranged between 0.69 and 7.50 per thousand, and between 2.07 and 13.80 per thousand in treated snails. The spontaneous MN levels in mussels averaged from 0.5 to 2.75 per thousand, and in snails from 1.56 to 2.00 per thousand. Our results suggest that haemolymph of both species represent an appropriate test tissue in environmental genotoxicity assessment.  相似文献   
6.
7.
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   
8.
Very similar genome sizes, similar karyotypes and heterochromatin organisation, and identical number/position of ribosomal loci characterise the common oak (Q. robur) and the cork oak (Q. suber), two distantly related oak species. Representational Difference Analysis (RDA) was used to subtract the genome of Q. suber from the genome of Q. robur in order to search for genome differentiation. A library of 400 clones (bearing RDA fragments) representing genome differences between the two species was obtained. Seven Q. robur-specific DNA sequences were analysed with respect to their molecular and chromosome organisation. All belong to the dispersed repetitive component of the genome, as revealed by Southern hybridisation and in situ hybridisation. They are present in the Q. robur genome in between 100 and 700 copies, and are distributed along the length of almost all chromosomes. A search for homologies between RDA fragments and sequences in Genbank revealed similarities of all RDA fragments with known retrotransposons. The RDA fragments were also tested for their presence/absence in the genomes of six additional oak species belonging to different phylogenetic groups, in order to examine the evolutionary dynamics of these DNA sequences.  相似文献   
9.
A three-dimensional finite element program is described which attempts to simulate the nonlinear mechanical behavior of an aging human face with specific reference to progressive gravimetric soft tissue descent. A cross section of the facial structure is considered to consist of a multilayered composite of tissues with differing mechanical behavior. Relatively short time (elastic-viscoplastic) behavior is governed by equations previously developed which are consistent with mechanical tests. The long time response is controlled by the aging elastic components of the tissues. An aging function is introduced which, in a simplified manner, models the observed loss of stiffness of these aging elastic components due to the history of straining as well as other physiological and environmental influences. Calculations have been performed for 30 years of exposure to gravitational forces. The deformations and stress distributions in the layers of the soft tissues are described. Overall, the feasibility of using constitutive relations which reflect the highly nonlinear elastic-viscoplastic behavior of facial soft tissues in finite element based three-dimensional mechanical analyses of the human face is demonstrated. Further developments of the program are discussed in relation to possible clinical applications. Although the proposed aging function produces physically reasonable long-term response, experimental data are not yet available for more quantitative validation.  相似文献   
10.
Comparative studies of the effect of benzyladenine (BA) on the yeast Saccharomyces cerevisiae, the bacterium Salmonella typhimurium, the shallot Allium ascalonicum and Chinese hamster fibroblast cells were performed. The tested substance had no mutagenic activity on yeast, bacteria and cultured fibroblast cells. Changes in mitotic activity and cell division abnormalities were observed after BA treatment in shallot root-tip cells.  相似文献   
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