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This clinical study is a first attempt to use autofluorescence for recurrence diagnosis of skin cancer in postoperative scars. The proposed diagnostic parameter is based on a reduction in scar autofluorescence, evaluated in the green spectral channel. The validity of the method has been tested on 110 postoperative scars from 56 patients suspected of non‐melanoma skin cancer, with eight patients (13 scars) available for the repeated examination. The recurrence diagnosis within a scar has been made after two subsequent autofluorescence check‐ups, representing the temporal difference between the scar autofluorescence amplitudes as a vector. The recognition of recurrence has been discussed to represent the significant deviations from the value of vector angle θ. This new autofluorescence‐based method can be easily integrated into the postoperative monitoring of surgical scars and can help diagnose the recurrence of skin cancer from the early stage of scar development.  相似文献   
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Abstract Probes containing the nod and hsn regions of Rhizobium meliloti and the fixABC genes of Rhizobium japonicum were used to perform hybridization experiments with endonuclease-restricted DNA from Azospirillum brasilense strains and 2 Azospirillum lipoferum strains. Homology to nod, hsn and fixA was found in the 4 Azospirillum strains.  相似文献   
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  1. At a so-called natural anaerobiosis during the first 48 hours of germination the concentration of ethanol in pea tissues increases (according to the cultivation conditions) up to 40 μmol per gram fresh weight.
  2. In a nitrogen atmosphere the content of ethanol in pea seedlings increases as well, and after a 90 hour incubation in N2 it can reach even 100 μmol ethanol per gram fresh weight. In older plants the content increases the most markedly in cotyledons, but considerable amounts were revealed also in stems and roots. Its increase in vegetative organs of plants cultivated both in light and darkness is more or less identical. Ethylalcohol can be formed by the vegetative organs themselves, as proved by the increase of this metabolite in plants deprived of reserve organs; in addition, however, it is evidently transported into them from reserve parts. Ethanol formed under anaerobiosis is catabolyzed after transferring plants to the air.
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D J Kihm  G J Leyer  G H An    E A Johnson 《Applied microbiology》1994,60(10):3854-3861
Listeria monocytogenes was highly resistant to hen egg white lysozyme in whole milk but was sensitive in media and in phosphate buffer. Methods to sensitize the pathogen to lysozyme in milk were investigated. Treatment of whole milk by cation exchange to remove minerals, particularly Ca2+ and Mg2+, slightly promoted inactivation of L. monocytogenes by lysozyme at 4 degrees C over a period of 6 days. Heat treatment (62.5 degrees C for 15 s) strongly sensitized L. monocytogenes to lysozyme in demineralized milk and in MES [2-(N-morpholino)ethanesulfonic acid] buffer. Addition of Ca2+ or Mg2+ to the demineralized milk restored resistance to lysozyme. Cells were more rapidly heat inactivated at 55 degrees C in demineralized milk containing lysozyme, and addition of Ca2+ to the demineralized milk restored the resistance to heat. The results indicate that minerals or mineral-associated components protect L. monocytogenes from inactivation by lysozyme and heat in milk, probably by increasing cell surface stability. The heat treatment of foods containing added lysozyme can probably play a significant role in producing microbiologically safe foods.  相似文献   
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The study has been performed on 3 acrylic resins used to fabricate removable dentures. Aim of the study was to detect possible differences in Candida albicans' adhesion within particular materials. Polished and non-polished samples were made, than these samples were sunk in precipitates containing Candida albicans material. Adhesion of Candida albicans to the surface of the materials occured within a concentration of 10. After 24 hours of incubation differences were found concerning the number of the plate cultures. Most of all plate cultures were observed on Lucitone 199, fewer on Zhermacryl, the poorest one was found on Palaxpress resin. Considerable number of plate cultures occured on non-polished samples relating to polished ones. After 48 hours of incubation further development of Candida albicans took place, with differences concerning various materials.  相似文献   
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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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