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991.
Zorrilla I Moriñigo MA Castro D Balebona MC Borrego JJ 《Journal of applied microbiology》2003,95(5):1106-1116
AIMS: Intraspecific differentiation and characterization of Vibrio alginolyticus strains isolated from cultured fish in Spain. MATERIALS AND RESULTS: Thirty-four Vibrio alginolyticus strains isolated from cultured fish were intraspecifically characterized on the basis of biochemical and exoenzymatic patterns, outer membrane protein (OMP) profiles, ribotyping and plasmid analyses. The typing methods used did not allow to group V. alginolyticus isolates on the basis of their sources of collection. A higher homogeneity was observed in OMP profiles. A high percentage of isolates were plasmidless. Ribotyping was the highest discriminatory typing method, as all the isolates tested presented 23 profiles using the HindIII restriction enzyme. On the basis of the ribotyping pattern, a similarity matrix and a dendrogram were constructed. CONCLUSIONS: The results obtained indicate that V. alginolyticus strains isolated from southwestern Spain belong to different clonal lineages. SIGNIFICANCE AND IMPACT OF THE STUDY: This study has shown differences with other similar studies carried out in other areas of Europe with strains of V. alginolyticus with respect to the clonal lineages of the strains isolated in southwestern Spain. 相似文献
992.
The Instituto Nacional de Investigaciones Nucleares (ININ, The National Nuclear Research Institute) received during 1997-1998 strong support of the International Atomic Energy Agency (IAEA), to establish the first and only one tissue bank (BTR ININ tissue bank) in Mexico that uses ionising radiation as sterilising agent. In that time, the BTR staff was trained in different tissue banks in several countries. Basic equipment for tissue processing donated by the IAEA was received in 1998. In July, 1999 the Mexican Health Secretariat gave the Sanitary License No. 1062000001 to the BTR to operate as an official organ and tissue bank. In August, 2001 the ININ and the Hospital Materno Infantil (HMI-ISSEMYM) signed an agreement to collaborate in amnion processing. The hospital is responsible for donor selection, serology tests, tissue procurement and washing, since this hospital is the BTR amnion supplier. The tissues are collected by ININ weekly with complete documentation. The BTR is responsible for processing: cleaning, air drying, packaging, labelling, microbiological control and sterilisation by gamma irradiation. The sterilised tissue is kept under quarantine for 6 months to obtain the results of the donor second serology test. From March to June, 2002 the BTR has processed 347.86 units (50 cm(2) each), is say, 17,393 cm(2). In addition, the pig skin xenograft process has been implemented and a protocol for clinical applications of it is running at the Hospital Central Sur de Alta Especialidad (PEMEX). Also the ININ tissue bank present status and perspectives are described. 相似文献
993.
Alvarez I Del Carmen Saldías M Wodowoz O Pérez Campos H Machin D Silva W Sueta P Pérez N Acosta Md Mdel C 《Cell and tissue banking》2003,4(2-4):173-178
The transplant law of 1971 based on informed consent, allows people to register their willingness to be a donor upon death. Since 1978 the governmental Institution, the National Bank of Organs and Tissues (BNOT), have been regulated the organ and tissue donation. Important progress was implemented in the BNOT and specially in the National Multi-tissue Bank (NMTB). Since 2001 with the participation in the IAEA Tissue Banking Programme, Quality System Management has been implemented in the NMTB. New bio-production for radiosterilized tissues for the first time and improved procedures were carried out. As a result an increased production of high-quality tissues was obtained and distributed for clinical use. 相似文献
994.
995.
Jaumot J Aviña A Eritja R Tauler R Gargallo R 《Journal of biomolecular structure & dynamics》2003,21(2):267-278
A procedure is described for the complete resolution of concentration profiles of oligonucleotide triplexes as a function of pH and temperature. The pH and temperature ranges at which triplexes are present and the relative concentrations of all the species involved in acid-base and conformational equilibria are successfully estimated from Multivariate Curve Resolution analysis of UV absorbance spectra recorded along acid-base titrations and melting experiments of single stranded, hairpin and their mixtures. The dependence of formation constants upon pH was successfully estimated. The hairpin h26 (5'-GAAGGAGGAGA-TTTT-TCTCCTCCTTC-3'), and the single stranded oligonucleotides s11CT (5'-CTTCCTCCTCT-3'), s11AG (5'-AGAGGAGGAAG-3') and s11TG (5'-TGTGGTGGTTG-3') were synthesized and their protonation and conformational equilibria were studied in detail. The procedure was shown to be especially useful for the study of triplexes with a low hypochromism upon formation. 相似文献
996.
The role of mitochondrial oxidative stress in aging 总被引:8,自引:0,他引:8
997.
Algorithm of hair restoration surgery in children 总被引:1,自引:0,他引:1
Hair is an inseparable element of external appearance of every human being. Although various fashion trends come and go, the lack of hair is for many a major aesthetic and psychological problem. Even if men's balding can be accepted as a natural phenomenon, hair loss in children is considered to be a condition demanding correction. During an 18-year period, 8440 hair restoration operations were performed at the Hair Clinic Poznan, in Poznan, Poland. Most patients were men treated for androgenic alopecia. Among the patients were 57 children in whom hair loss resulted from hereditary factors, perinatal traumas, radiotherapy, and mechanical, thermal, and chemical damage. Methods of restoration were adjusted to type of hair loss, patient age, and ability to cooperate with the surgeon. In cases of single massive scars, skin flap correction was usually used. The flaps were prepared with the use of expanders. In cases of numerous scattered defects or considerable thinning of the scalp, the method of choice was hair transplantation. The "four-hand stick-and-place" technique developed by the authors enabled the surgeon to quickly and precisely carry out the procedure. Application of varied surgery techniques in scalp reconstruction procedures in children gave very good aesthetic results with a minimal complication rate. 相似文献
998.
El-Hamdaoui A. Redondo-Nieto M. Torralba B. Rivilla R. Bonilla I. Bolaños L. 《Plant and Soil》2003,251(1):93-103
The effects of different levels of B (from 9.3 to 93 M B) and Ca (from 0.68 to 5.44 mM Ca) on plant development, nitrogen fixation, and mineral composition of pea (Pisum sativum L. cv. Argona) grown in symbiosis with Rhizobium leguminosarum bv. viciae 3841 and under salt stress, were analysed. The addition of extra B and extra Ca to the nutrient solution prevented the reduction caused by 75 mM NaCl of plant growth and the inhibition of nodulation and nitrogen fixation. The number of nodules recovered by the increase of Ca concentration at any B level, but only nodules developed at high B and high Ca concentrations could fix nitrogen. Addition of extra B and Ca during plant growth restored nodule organogenesis and structure, which was absolutely damaged by high salt. The increase in salt tolerance of symbiotic plants mediated by B and Ca can be co-related with the recovery of the contents of some nutrients. Salinity produced a decrease of B and Ca contents both in shoots and in nodulated roots, being increased by the supplement of both elements in the nutrient solution. Salinity also reduced the content in plants of other nutrients important for plant development and particularly for symbiotic nitrogen fixation, as K and Fe. A balanced nutrition of B and Ca (55.8 M B, 2.72 mM Ca) was able to counter-act the deficiency of these nutrients in salt-stressed plants, leading to a huge increase in salinity tolerance of symbiotic pea plants. The necessity of nutritional studies to successfully cultivate legumes in saline soils is discussed and proposed. 相似文献
999.
Baroja-Fernández E Muñoz FJ Saikusa T Rodríguez-López M Akazawa T Pozueta-Romero J 《Plant & cell physiology》2003,44(5):500-509
By using barley seeds, developmental changes of ADPglucose (ADPG)-producing sucrose synthase (SS) and ADPG pyrophosphorylase (AGPase) have been compared with those of UDPglucose (UDPG), ADPG, sucrose (Suc) and starch contents. Both ADPG-synthesizing SS and AGPase activity patterns were found to correlate well with those of ADPG and starch contents. Remarkably, however, maximal activities of ADPG-synthesizing SS were found to be several fold higher than those of AGPase throughout seed development, the highest rate of starch accumulation being well accounted for by SS. Kinetic analyses of SS from barley endosperms and potato tubers in the Suc cleavage direction showed similar K(m) values for ADP and UDP, whereas apparent affinity for Suc was shown to be higher in the presence of UDP than with ADP. Moreover, measurements of transglucosylation activities in starch granules incubated with purified SS, ADP and [U-(14)C]Suc revealed a low inhibitory effect of UDP. The ADPG and UDPG contents in the transgenic S-112 SS and starch deficient potato mutant [Zrenner et al. (1995) Plant J. 7: 97] were found to be 35% and 30% of those measured in wild-type plants, whereas both glucose-1-phosphate and glucose-6-phosphate contents were found to be normal as compared with those of wild-type plants. The overall results thus strongly support a novel gluconeogenic mechanism reported previously [Pozueta-Romero et al. (1999) CRIT: Rev. Plant Sci. 18: 489] wherein SS catalyses directly the de novo production of ADPG linked to starch biosynthesis in heterotrophic tissues of plants. 相似文献
1000.
Following a toxic flood from a mine spill that affected over 45 km2 in Southern Spain, experiments were conducted in 1999 to test the feasibility of using crops for phytoremediation of the area, after the mechanical removal of the mud. Two cereals, barley and triticale, and two Brassicaspp., rapeseed and ethiopian mustard, were planted in three contaminated plots, 50 × 100 m each, and in a control plot outside the affected area. Soil and plant contents of As, Cd, Cu, Pb, Tl and Zn were measured and bioaccumulation coefficients (BC) were calculated at maturity. The four crops tested accumulated Cd and Zn in the above-ground biomass only in the plot on acid soil. Both species of Brassica accumulated Tl (average BC of 3.6 and 1.4 for rapeseed and mustard, respectively, in contaminated plots). None of the four crop plants accumulated As, Cu and Pb under the experimental conditions. Maximum plant uptake values from soil were 5.4 mg m–2 of As, 0.54 mg m–2 of Cd, 9.7 mg m–2 of Cu, 7.0 mg m–2 of Pb, 3.4 mg m–2 of Tl, and 260 mg m–2 of Zn. Total crop uptake gave estimates for successful phytoremediation of at least five decades, casting doubts on the feasibility of using these crops for decontamination of the area. Nevertheless, cereal grains had mineral contents below toxicity levels for livestock, therefore it might be possible to use these crops for livestock feed while reducing deep percolation and gradually removing metals from polluted soils. 相似文献