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81.
One hundred and twenty-two samples of cheeses made from goat and sheep milk and a mixture of the two types, produced in Southern Italy by industrial establishments or artisans, were analysed for the detection of fungal contamination and the presence of potentially toxigenic moulds. Only organoleptically acceptable cheeses without evident fungal contamination were studied. Among these, 40 were unripened, 30 medium and 52 long ripened cheeses. Moulds were found in 54 of the 122 analysed samples (44.3%). The most contaminated cheeses were the medium and long ripened ones (46.3% and 35.2%), and the industrial cheeses (59.1%). The artisan cheeses were the least contaminated (26.8%). Among the cheeses that tested positive, Penicillium species were the most frequently isolated (72.9%), followed by Geotrichum spp. (7.3%), Aspergillus spp. (4.2%) and Mucor spp. (4.2%). The potentially toxigenic species within the genera Penicillium, Aspergillus and Fusarium were mainly detected in sheep cheeses.  相似文献   
82.
The mitochondrial paralog of the Hsp90 chaperone family TRAP1 is often induced in tumors, but the mechanisms controlling its expression, as well as its physiological functions remain poorly understood. Here, we find that TRAP1 is highly expressed in the early stages of Zebrafish development, and its ablation delays embryogenesis while increasing mitochondrial respiration of fish larvae. TRAP1 expression is enhanced by hypoxic conditions both in developing embryos and in cancer models of Zebrafish and mammals. The TRAP1 promoter contains evolutionary conserved hypoxic responsive elements, and HIF1α stabilization increases TRAP1 levels. TRAP1 inhibition by selective compounds or by genetic knock-out maintains a high level of respiration in Zebrafish embryos after exposure to hypoxia. Our data identify TRAP1 as a primary regulator of mitochondrial bioenergetics in highly proliferating cells following reduction in oxygen tension and HIF1α stabilization.Subject terms: Cancer metabolism, Cell signalling  相似文献   
83.
Virus removal filtration is a critical step in the manufacture of monoclonal antibody products, providing a robust size-based removal of both enveloped and non-enveloped viruses. Many monoclonal antibodies show very large reductions in filtrate flux during virus filtration, with the mechanisms governing this behavior and its dependence on the properties of the virus filter and antibody remaining largely unknown. Experiments were performed using the highly asymmetric Viresolve® Pro and the relatively homogeneous Pegasus™ SV4 virus filters using a highly purified monoclonal antibody. The filtrate flux for a 4 g/L antibody solution through the Viresolve® Pro decreased by about 10-fold when the filter was oriented with the skin side down but by more than 1000-fold when the asymmetric filter orientation was reversed and used with the skin side up. The very large flux decline observed with the skin side up could be eliminated by placing a large pore size prefilter directly on top of the virus filter; this improvement in filtrate flux was not seen when the prefilter was used inline or as a batch prefiltration step. The increase in flux due to the prefilter was not related to the removal of large protein aggregates or to an alteration in the extent of concentration polarization. Instead, the prefilter appears to transiently disrupt reversible associations of the antibodies caused by strong intermolecular attractions. These results provide important insights into the role of membrane morphology and antibody properties on the filtrate flux during virus filtration.  相似文献   
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Two hundred and sixteen consecutive patients seen for the first time with symptomatic haemorrhoids entered trials of conservative and minor surgical treatment. They were divided into two groups according to their pretreatment maximal anal pressure. Patients with pressures of 100 cm H2O (73.7 mm Hg) or more (108 patients) were treated by anal dilatation (37), sphincterotomy (34), or high-fibre diet (37). Four and 12 months later anal dilatation had produced significantly better results than sphincterotomy or diet. Furthermore, anal dilatation was the only treatment associated with a significant reduction in anal pressure at four and 12 months. Patients with pressures under 100 cm H2O (108 patients) were treated by rubber-band ligation (35), cryosurgery (36), or diet (37). Four and 12 months later significantly more patients were improved by rubber-band ligation than by cryosurgery or diet. These results suggest that haemorrhoids in patients with excessive activity of the internal anal sphincter are best treated by anal dilatation and that in all other patients rubber-band ligation is the treatment of choice.  相似文献   
86.

Background  

Receptor protein tyrosine phosphatase rho (RPTPρ, gene symbol PTPRT) is a member of the type IIB RPTP family. These transmembrane molecules have been linked to signal transduction, cell adhesion and neurite extension. The extracellular segment contains MAM, Ig-like and fibronectin type III domains, and the intracellular segment contains two phosphatase domains. The human RPTPρ gene is located on chromosome 20q12-13.1, and the mouse gene is located on a syntenic region of chromosome 2. RPTPρ expression is restricted to the central nervous system.  相似文献   
87.
The relationship between the toxicities of crude extracts and purified toxins of Fusarium spp. belonging to the section Sporotrichiella has been assessed. Toxicity was determined on the basis of death of Artemia salina larvae and of viability and blastogenic response of bovine and human lymphocytes. Trichothecene-producing strains of Fusarium sporotrichioides and Fusarium poae were toxic to A. salina and to lymphocyte blastogenesis. A strain of Fusarium tricinctum, producing visoltricin and chlamydosporol, induced differentiated activity in different bioassays (toxicity to A. salina but only minor activity against lymphocyte blastogenesis). Other, non-toxin-producing strains of Fusarium chlamydosporum, F. poae, and F. tricinctum were not active in the tested biosystems.  相似文献   
88.
Since publication of the first record of Eichhornia crassipes in Cameroon in 1997, the weed has become highly invasive in the Wouri River Basin. Between June and September 2014, a socio-economic survey using participatory and qualitative methods was undertaken in the riparian villages of the Wouri River Basin to assess the perception of respondents to the presence of water hyacinth. The survey revealed that water hyacinth was a significant threat to activities along the river, which included fishing, sand extraction and river transportation. The presence of water hyacinth mats reduced catch rates of several common fish species, river transportation by 75%, and significantly reduced the income for sand extraction. Cameroon employs manual clearing of water hyacinth; however, respondents indicated they would consider other control methods, provided they do not have any negative impacts.  相似文献   
89.
In previous researches spontaneous nocturnal sleep in chronic chorea showed short total sleep time, prolonged sleep latency, several awakenings, reduction of REM sleep time, decrease in slow waves sleep, strong increase in sleep spindles. Some of these alterations improved after therapy with lithium, haloperidol and lithium, pimozide. Since the concentration of GABA has been found to be reduced in patients with Huntington's chorea, we studied the effect of sodium valproate, a drug that enhances GABA inhibition in cerebral cortex, on nocturnal sleep of six patients with chronic chorea, aged 35 to 60 years (mean 47,3). Nocturnal polygraphic records (EEG, EOG, EMG of chin muscles) were carried out after two consecutive adjustative nights, both before therapy and after sixty days of treatment with sodium valproate (800-2000 mg four times a day, orally). Moreover, chorea, finger dexterity and gait were each rated once a week by three members of the research team and by one independent observer, using a five points rating scale from 0 (normal) to 4 (very severely abnormal). Before therapy the sleep parameters were in accordance with our previous results in chronic choreic patients. After two months therapy we observed a statistically significant (P less than 0.05) reduction of awakenings and of wake time. Sodium valproate produced no objective change in any of the parameters of motor function studied. If singularly examined, however, a reduction of chorea was obtained only in a patient, whose favourable response to therapy was also demonstrated by the normalization of other sleep parameters. These data stress the importance of sleep study in extrapyramidal disorders and suggest a different involvement of GABA-mediated transmission in various patients with chronic chorea.  相似文献   
90.
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