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611.
BACKGROUND: Horseshoe kidney is a renal congenital anomaly. It is the result of the fusion of either upper or lower poles of both kidneys, appearing as a horseshoe-shaped structure. This anomaly is very frequent: it can be found in about 1 of every 50-1,000 autopsies). CASE: Computed tomography performed routinely after pancreatitis in a 37-year-old female showed a retroperitoneal mass of uncertain origin. Fine needle aspiration cytology (FNAC) smears evidenced normal renal tissue. Urography confirmed the diagnosis of horseshoe kidney. CONCLUSION: This is the first reported case of horseshoe kidney diagnosed by FNAC. It demonstrates the utility of FNAC for diagnosis of retroperitoneal masses, especially if they are asymptomatic. 相似文献
612.
613.
Variation in Resistance of Natural Isolates of Escherichia coli O157 to High Hydrostatic Pressure, Mild Heat, and Other Stresses 总被引:4,自引:0,他引:4
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Amparo Benito Georgia Ventoura Maria Casadei Tobin Robinson Bernard Mackey 《Applied microbiology》1999,65(4):1564-1569
Strains of Escherichia coli O157 isolated from patients with clinical cases of food-borne illness and other sources exhibited wide differences in resistance to high hydrostatic pressure. The most pressure-resistant strains were also more resistant to mild heat than other strains. Strain C9490, a representative pressure-resistant strain, was also more resistant to acid, oxidative, and osmotic stresses than the pressure-sensitive strain NCTC 12079. Most of these differences in resistance were observed only in stationary-phase cells, the only exception being acid resistance, where differences were also apparent in the exponential phase. Membrane damage in pressure-treated cells was revealed by increased uptake of the fluorescent dyes ethidium bromide and propidium iodide. When strains were exposed to the same pressure for different lengths of time, the pressure-sensitive strains took up stain sooner than the more resistant strain, which suggested that the differences in resistance may be related to susceptibility to membrane damage. Our results emphasize the importance of including stress-resistant strains of E. coli O157 when the efficacy of a novel or mild food preservation treatment is tested. 相似文献
614.
Association of Isozymes with a Reciprocal Translocation in Cultivated Rye (SECALE CEREALE L.) 总被引:1,自引:0,他引:1
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In rye (Secale cereale L. cv. "Ailés") the progeny of a cross between a structural heterozygote for a reciprocal translocation (involving the 1R chromosome) and a homozygote for the standard chromosome arrangement were analyzed for the electrophoretic patterns of eight different leaf isozymes and also for their meiotic configuration at metaphase I.——The Got-3 and Mdh-2b loci are linked to each other and also to the reciprocal translocation. The Mdh-2b locus is located in the interstitial segment of the 3Rq chromosome arm, with an estimated distance of 8 cM to the breakpoint. Therefore, the reciprocal translocation involves the 1R and 3R chromosomes.——Also, the Mdh-1 and 6-Pgd-2 loci are linked (16 ± 3 cM) and have been located on the 2Rq arm. Finally, the Per-3 and Per-4 loci are located on the 2Rp chromosome arm at an estimated distance of 26 ± 4 cM. 相似文献
615.
5'-nucleotidase activity of murine T-cell subpopulations separated according to their Lyt2 and L3T4 phenotypes 总被引:1,自引:0,他引:1
Murine T lymphocytes were separated by "panning" into four subpopulations, according to their Lyt2 and L3T4 phenotypes: Lyt2+L3T4+, Lyt2-L3T4-, Lyt2+L3T4-, and Lyt2-L3T4+. The activity of ecto-5'-nucleotidase in each subpopulation was measured. 5'-Nucleotidase activity was undetectable in Lyt2+L3T4+ cortical cells but was expressed in medullary Lyt2-L3T4+ and Lyt2+L3T4- T lymphocytes. The small cortical subpopulation of thymocyte precursors with the Lyt2-L3T4- phenotype expressed levels of 5'-nucleotidase comparable to the levels of medullary, mature lymphocytes. These results suggest that the use of ecto-5'-nucleotidase as a marker of the degree of T-cell maturation is questionable. 相似文献
616.
A. M. Figueiras M. T. González-Jaén C. Benito 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1986,72(6):826-832
Summary The alcohol dehydrogenase (ADH), phosphoglucose mutase (PGM), glucosephosphate isomerase (GPI), glutamic oxaloacetic transaminase (GOT), malate dehydrogenase (MDH), leaf esterases (ESTL), leaf acid (ACPH) and endosperm alkaline (PHE) phosphatases, leaf peroxidases (PERL) zymogram phenotypes of Triticum aestivum, Agropyron intermedium, Triticum aestivum — Agropyron intermedium octoploids and six Agropyron intermedium chromosome additions to Triticum aestivum and two ditelocentric addition lines were determined. It was found that the six disomic chromosome addition lines and one ditelocentric chromosome addition line could be distinguished from one another and from the other possible lines on the basis of the zymogram phenotypes of these isozymes. The structural gene Acph-X1 was located on Agropyron chromosome L1, the genes Got-X3 and Mdh-X2 on chromosome L2, the gene Gpi-X1 on chromosome L3, the genes Adh-X1, Pgm-X1 and Phe-3 on chromosome L4, gene Perl-1 on chromosome L5 and the gene Estl-2 on chromosome L7 and chromosome arm L7d2. These gene locations provide evidence of homoeology between Agropyron chromosomes L1, L2, L3, L4, L5 and L7 and the Triticum aestivum chromosomes of homoeologous groups 7, 3, 1, 4, 2 and 6, respectively. 相似文献
617.
A. M. Figueiras M. T. González-Jaén C. Benito 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1987,73(5):683-689
Summary Genetic analyses were conducted on alkaline phosphatases of the endosperm of dry kernels and leaf acid phosphatases in four open pollinated and one inbred line of cultivated rye (Secale cereale L.). A total of seven alkaline phosphatase isozymes were observed occurring at variable frequencies in the different cultivars analyzed. We propose that at least five loci control the alkaline phosphatases of rye endosperm — Alph-1, Alph-2, Alph-3, Alph-4 and Alph-5 — all of which have monomeric behaviour. The leaf acid phosphatases are controlled by one locus and have a dimeric quaternary structure. All loci coding for alkaline phosphatase isozymes showed one active, dominant allele and one null, recessive allele, except for the locus Alph-3 which showed two active, dominant alleles and one null, recessive one. The linkage analyses suggest the existence of two linkage groups for alkaline phosphatases: one of them would contain Alph-2, Alph-4, Alph-5 and the locus/loci coding isozymes 6 and 7. This linkage group is located in the 7RS chromosome arm. The other group would include Alph-1 and Alph-3 loci, being located in the 1RL chromosome arm. Leaf acid phosphatases have been previously located in the 7RL chromosome arm. Our data also support an independent relationship between loci controlling the endosperm alkaline phosphatases and leaf acid phosphatases. 相似文献
618.
Summary Endogenous and exogenous volatile substances were analyzed during 30 days' incubation of four cultivars of thePrunus avium species grown in vitro on a proliferation medium. Cultivars Bigarreau Moreau and Bigarreau Burlat show photosynthetic capability
at 35 μmol·m−2·s−1; oxygen concentration slightly increased (22 to 24%), carbon dioxide was lowered to less than 300 μ·liter−1, and low ethylene (0.8 to 1.2·liter−1) accumulation was recorded. Quite different headspace evolution was observed during growth of cultivars Victoria and Casavecchia:
a large oxygen concentration decrease was accompanied by a sharp carbon dioxide increase (19%) and ethylene boost (4 to 5
μl·liter−1). The evolution of these gaseous metabolites has been correlated to photosynthetic incapability and respiratory stress responsible
for leaf yellowing and tissue softening observed when acetaldehyde and ethanol started to form in cultivars Victoria and Casavecchia.
Dry and fresh weight were measured, and no substantial difference was recorded among cultures with low and high photosynthetic
capability. Evidence is reported that different genotypes within the same species may follow different metabolic pathways. 相似文献
619.
Benito Righetti David M. Reid Trevor A. Thorpe 《In vitro cellular & developmental biology. Plant》1996,32(4):290-294
Summary The rate of metabolism and biosynthetic processes makein vitro cultures very sensitive to environmental changes, and therefore subject to physiological and morphological alterations leading
to senescence in the short term. The effect of three different calibrated atmospheric compositions were studied duringin vitro culture ofPrunus avium shoots. At 0.034% CO2-21% O2 (vol/vol), which stimulate the natural atmosphere, the highest growth rate and chlorophyll content were recorded. When grown
at 0.09% CO2-8% O2 (vol/vol), a favorable condition for photosynthesis and growth, cultures showed a higher percentage of dry matter and elevated
ethylene production, but total chlorophyll was lower. These shoots were also highly lignified and fibrous with red pigmentation
along the leaves and stems. At 0% CO2-21% O2 (vol/vol), in contrast, growth and ethylene formation were inhibited; chlorophyll content was lowest in comparison with the
other two environmental conditions, but regreening of tissues was observed after the first half of the culture period. Senescence
symptoms, as indicated by decreased chlorophyll, appeared after about 18 d of culture for tissues grown in CO2-containing atmospheres. These experiments provided evidence that in CO2-enriched cultures biomass production steadily increased even when chlorophyll decreased. A possible role of CO2 in promoting tissue-senescence through activation of photooxidative events and ethylene synthesis is discussed. 相似文献
620.