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51.
The fungal revolution taking place in otorhinology inspired us to study the frequency of occurrence of fungi in the nasal mucus of chronic rhinosinusitis (CRS) patients (with or without polyposis) in order to evaluate the incidence of eosinophilic fungal sinusitis in CRS patients. Ninety-six samples were examined from patients with CRS. In 74 cases mucus was collected non-invasively, and in 22 cases during operation. The Gram-stained direct smears of all samples were also evaluated. Bacteria and fungi colonizing in the mucus were detected by culturing method. The control group consisted of 50 healthy volunteers. Typical aerobic pathogenic bacteria could be isolated from 34 patients. Fifty-seven aerobic bacteria were isolated, i.e. 1.6 bacteria/positive patient with a maximum of 3 different bacteria/sample. The most frequently isolated bacteria were Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Streptococcus pneumoniae, and Haemophilus influenzae. Yeasts and moulds could be detected from 79 patients (83%): Candida albicans, Candida spp., Aspergillus spp., Cladosporium spp, and Penicillium spp. were isolated most frequently. Altogether 237 yeasts and moulds were isolated, i.e. 3.0 different fungi/positive patient, with a maximum of 5 different fungi/sample. In the control group aerobic pathogens were not isolated, only apathogenic species. Fungi were isolated from 22 healthy patients (44%). These data indicate that fungi are frequently involved in the aetiology of CRS. IgE-medicated hypersensitivity to fungal allergens could not be proven in our patients.  相似文献   
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Hemangiomas of infancy are very common tumors, but they are heterogeneous in their behavior. A small, but significant, subset causes medical complications or permanent disfigurement, but due to their heterogeneity, there is no appropriate "one size fits all" approach to management. In addition, the rapid evolution of this tumor over the first weeks-to-months of infancy renders even more difficult the task of predicting which infants will have medical complications or permanent disfigurement. This article outlines the clinical characteristics that help to stratify hemangiomas into those which are high risk, and likely to require either active treatment or closer scrutiny, and those which are low risk, and likely to behave in an innocuous manner. Five major factors are emphasized: the age of the child, the location of the hemangioma(s), the total number of hemangiomas present, the hemangioma subtype, and the presence and nature of dermal involvement.  相似文献   
56.
Three phosphatidylinositol 4-kinase isoforms, PI4K 230, 92 and 55 have been cloned and sequenced allowing a much wider characterization than the previously employed enzymological typing into type II and III enzymes. PI4K 230 and 92 contain a highly conserved catalytic core, PI4K55 one with a much lower degree of similarity. Candidate kinase motifs, deduced from the protein kinase super family, are absolutely conserved in all isoforms. Kinase activities are described based on their sensitivity and reactivity towards wortmannin, phenylarsine oxide (PAO) and 5'-p-fluorosulfonylbenzoyladenosine (FSBA). Localization of all isoforms in the cell is reported. All enzymes contain nuclear localization and export sequence motifs (NLS and NES) leading to the expectation that they can be transferred to the nucleus. PI4K230 has been found in the nucleolus, PI4K92 in the nucleus, additionally further broadening the function of these enzymes. In the cytoplasm of neuronal cells, PI4K230 is distributed evenly on membranes that are ultra structurally cisterns of the rough endoplasmatic reticulum, outer membranes of mitochondria, multivesicular bodies, and are in close vicinity of synaptic contacts. PI4K92 is functionally characterized as a key enzyme regulating Golgi disintegration/reorganization during mitosis probably via phosphorylation by cyclin-dependent kinases on well-defined sites. PI4K55 is involved in the production of second messengers, diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (InsP3) at the plasma membrane, moreover, in the endocytotic pathway in the cytoplasm.  相似文献   
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Parameters of [3H]uridine binding to synaptic membranes isolated from rat brain cortex (K(D)=71+/-4 nM, B(max)=1.37+/-0.13 pmol/mg protein) were obtained. Pyrimidine and purine analogues displayed different rank order of potency in displacement of specifically bound [3H]uridine (uridine>5-F-uridine>5-Br-uridine approximately adenosine>5-ethyl-uridine approximately suramin>theophylline) and in the inhibition of [14C]uridine uptake (adenosine>uridine>5-Br-uridine approximately 5-F-uridine approximately 5-ethyl-uridine) into purified cerebrocortical synaptosomes. Furthermore, the effective ligand concentration for the inhibition of [14C]uridine uptake was about two order of magnitude higher than that for the displacement of specifically bound [3H]uridine. Adenosine evoked the transmembrane Na(+) ion influx, whereas uridine the transmembrane Ca(2+) ion influx much more effectively. Also, uridine was shown to increase free intracellular Ca(2+) ion levels in hippocampal slices by measuring Calcium-Green fluorescence. Uridine analogues were found to be ineffective in displacing radioligands that were bound to various glutamate and adenosine-recognition and modulatory-binding sites, however, increased [35S]GTPgammaS binding to membranes isolated from the rat cerebral cortex. These findings provide evidence for a rather specific, G-protein-coupled site of excitatory action for uridine in the brain.  相似文献   
58.
The formation of a disulfide bond between adjacent cysteine residues is accompanied by the formation of a tight turn of the protein backbone. In nearly 90% of the structures analyzed a type VIII turn was found. The peptide bond between the two cysteines is in a distorted trans conformation, the omega torsion angle ranges from 159 to -133 degrees, with an average value of 171 degrees. The constrained nature of the vicinal disulfide turn and the pronounced difference observed between the oxidized and reduced states, suggests that vicinal disulfides may be employed as a 'redox-activated' conformational switch.  相似文献   
59.
Two novel monoclonal antibodies were raised and used to study the expression of laminin (Ln) alpha1-chain in developing and adult human tissues. In both fetal and adult kidney, a distinct immunoreactivity was seen in basement membranes (BM) of most proximal tubules but not in the distal tubular or glomerular BM or in the basal laminae of blood vessels. Immunoprecipitation of metabolically labeled cultured human renal proximal tubular cells showed an abundant production and deposition of Ln alpha1-chain to the extracellular matrix, suggestive of an epithelial origin of kidney Ln-1. Quantitative cell adhesion experiments with JAR choriocarcinoma cells showed that purified human Ln-1 is a good substrate for cell adhesion that it is differently recognized by integrin receptors when compared to mouse Ln-1. In fetal and adult testes immunoreactivity was solely confined to BM of the seminiferous epithelium. In the airways BM-confined reaction was only seen in fetal budding bronchial tubules (16-19 weeks) at the pseudoglandular stage of development. In the skin a distinct immunoreactivity was confined to BM of developing hair buds but not in epithelial BMs of adult epidermis or of epidermal appendages. In other adult tissues, immunoreactivity was found in BMs of thyroid, salivary, and mammary glands as well as in BMs of endometrium and endocervix, but not of ectocervix or vagina. No immunoreactivity was found in BMs of most of the digestive tract, including the liver and pancreas, except for BMs of esophageal submucosal glands and duodenal Brunner's glands. In fetal specimens, BMs of the bottoms of the intestinal and gastric glands were positive. Basal laminae of blood vessels were generally negative for Ln alpha1 chain with the exception of specimens of both fetal and adult central nervous system in which immunoreactivity for Ln alpha1 chain was prominently confined to capillary walls. The results suggest that outside the central nervous system, Ln alpha1 chain shows a restricted and developmentally regulated expression in BMs of distinct epithelial tissues.  相似文献   
60.
Random aliphatic-aromatic copolyesters synthesized from 1,4-butanediol, adipic acid, and terephthalic acid (BTA) have excellent thermal and mechanical properties and are biodegradable by mixed cultures (e.g., in compost). Over 20 BTA-degrading strains were isolated by using compost as a microbial source. Among these microorganisms, thermophilic actinomycetes obviously play an outstanding role and appear to dominate the initial degradation step. Two actinomycete strains exhibited about 20-fold higher BTA degradation rates than usually observed in a common compost test. These isolates were identified as Thermomonospora fusca strains. They appeared to be particularly suitable for establishment of rapid degradation tests and were used in comparative studies on the biodegradation of various polyesters.  相似文献   
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