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排序方式: 共有174条查询结果,搜索用时 15 毫秒
51.
Lopandic K Gangl H Wallner E Tscheik G Leitner G Querol A Borth N Breitenbach M Prillinger H Tiefenbrunner W 《FEMS yeast research》2007,7(6):953-965
To evaluate the influence of the genomic properties of yeasts on the formation of wine flavour, genotypic diversity among natural Saccharomyces cerevisiae strains originating from grapes collected in four localities of three Austrian vine-growing areas (Thermenregion: locations Perchtoldsdorf and Pfaffst?tten, Neusiedlersee-Hügelland: location Eisenstadt, Neusiedlersee: location Halbturn) was investigated and the aroma compounds produced during fermentation of the grape must of 'Grüner Veltliner' were identified. Amplified fragment length polymorphism analysis (AFLP) showed that the yeast strains cluster in four groups corresponding to their geographical origin. The genotypic analysis and sequencing of the D1/D2 domain of 26S rRNA encoding gene and ITS1/ITS2 regions indicated that the Perchtoldsdorf strains were putative interspecies hybrids between S. cerevisiae and Saccharomyces kudriavzevii. Analysis of the aroma compounds by GS/MS indicated a region-specific influence of the yeasts on the chemical composition of the wines. The aroma compound profiles generated by the Perchtoldsdorf strains were more related to those produced by the Pfaffst?tten strains than by the Eisenstadt and Halbturn strains. Similar to the Pfaffst?tten yeasts, the putative hybrid strains were good ester producers, suggesting that they may influence the wine quality favourably. 相似文献
52.
Kristek J Dmitrović B Kurbel S Sakić K Krajinović Z Blazicević V Has B Marjanović K 《Collegium antropologicum》2007,31(4):1043-1047
The aim of this paper is to determine similarities and differences between tumor cell subclones in cases of ductal invasive breast carcinoma, and which occupy primary tumor and local axillary lymph metastases. The tumor growth fraction evaluated by Ki-67 was analyzed along with the expression level of estrogen and progesterone receptors, protein p53, proto-oncogene protein bcl-2 and cathepsin D in 60 patients. Metastatic lymph node in axilla has a higher growth fraction of the tumor cells than the primary tumor (p = 0.045), as well as the higher level of bcl-2 overexpression (p = 0.014). No statistically significant difference was found in the presence of immunohistochemically identified estrogen receptors (p = 0.161) and progesterone receptors (p = 0.081) between the primary tumor and the metastatic lymph node in axilla. Likewise, no difference was found between the immunohistochemical evaluation of p53 (p = 0.356) and cathepsin D activity (p = 0.928). A higher growth fraction of the tumor cells and the higher level of bcl-2 overexpression in metastatic tumor cells indicate the more aggressive cell subclones. This study does not support the routine testing of both primary tumor and locoregional metastasis to evaluate the breast cancer hormone receptor status. 相似文献
53.
Helianthus maximiliani is one of the wild Helianthus species with the genes for resistance to many pathogens including Sclerotinia sclerotiorum. Unfortunately, a transfer of disease resistance genes from this species into the cultivated sunflower is limited by its poor crossability with the cultivated sunflower and sterility of interspecific hybrids. To overcome this problem, mesophyll protoplasts of Sclerotinia sclerotiorum-resistant clone of H. maximiliani were electrically fused with etiolated hypocotyl protoplasts of the cultivated sunflower inbred line PH-BC1-91A. Fusion products were embedded in agarose droplets and subjected to different regeneration protocols. Developed microcalluses were released from the agarose and transferred into solid media. Shoot regeneration was achieved by culture of calluses on regeneration medium containing 2.2 mg l−1 BAP and 0.01 mg l−1 NAA after the treatment with a high concentration of 2,4 D for a limited period of time. A morphological and RAPD analysis confirmed a hybrid nature of the regenerated plants. 相似文献
54.
Characteristics and transferability of new apple EST-derived SSRs to other Rosaceae species 总被引:1,自引:0,他引:1
Ksenija Gasic Yuepeng Han Sunee Kertbundit Vladimir Shulaev Amy F. Iezzoni Ed W. Stover Richard L. Bell Michael E. Wisniewski Schuyler S. Korban 《Molecular breeding : new strategies in plant improvement》2009,23(3):397-411
Genic microsatellites or simple sequence repeat markers derived from expressed sequence tags (ESTs), referred to as EST–SSRs,
are inexpensive to develop, represent transcribed genes, and often have assigned putative function. The large apple (Malus × domestica) EST database (over 300,000 sequences) provides a valuable resource for developing well-characterized DNA molecular markers.
In this study, we have investigated the level of transferability of 68 apple EST–SSRs in 50 individual members of the Rosaceae
family, representing three genera and 14 species. These representatives included pear (Pyrus communis), apricot (Prunus armeniaca), European plum (P. domestica), Japanese plum (P. salicina), almond (P. dulcis), peach (P. persica), sour cherry (P. cerasus), sweet cherry (P. avium), strawberry (Fragaria vesca, F. moschata, F. virginiana, F. nipponica, and F. pentaphylla), and rose (Rosa hybrida). All 68 primer pairs gave an amplification product when tested on eight apple cultivars, and for most, the genomic DNA-derived
amplification product matched the expected size based on EST (in silico) data. When tested across members of the Rosaceae, 75% of these primer pairs produced amplification products. Transferability
of apple EST–SSRs across the Rosaceae ranged from 25% in apricot to 59% in the closely related pear. Besides pear, the highest
transferability of these apple EST–SSRs, at the genus level, was observed for strawberry and peach/almond, 49 and 38%, respectively.
Three markers amplified in at least one genotype within all tested species, while eight additional markers amplified in all
species, except for cherry. These 11 markers are deemed good candidates for a widely transferable Rosaceae marker set provided
their level of polymorphism is adequate. Overall, these findings suggest that transferability of apple EST–SSRs across Rosaceae
is varied, yet valuable, thereby providing additional markers for comparative mapping and for carrying out evolutionary studies. 相似文献
55.
Lee JS Jeftinija K Jeftinija S Stromer MH Scanes CG Anderson LL 《Histochemistry and cell biology》2004,122(6):571-577
The objective of this immunohistochemical study was to identify the spatial distribution patterns of growth hormone (GH) secreting cells (somatotrophs) in the newborn and prepubertal porcine pituitary. No differences were observed among the total somatotrophs per unit area across the three ages. There were, however, changes in spatial distribution of somatotrophs in porcine pituitary with developmental age. Distinctive characteristics of the pattern included a high population of somatotrophs (44±1.2; mean ± standard error of the mean per 30,495 m2) in regions 1 and 5 and a low population (22±1.4) in regions 2 and 4 at each level (P<0.05). Somatotrophs increased 55% in region 3 from proximal to distal levels at all ages. With increasing age, however, somatotrophs in region 3 at the proximal level decreased 33%. From these results, we suggest that there may be regional specificity of cellular differentiation and transformation to facilitate GH secretion to meet the need for endocrine regulation as the animal ages. 相似文献
56.
Karaman K Culić S Erceg I Culić V Siniilć A Salamunić I Znaor L 《Collegium antropologicum》2005,29(Z1):123-126
Intracameral tissue plasminogen activator (t-PA) application in a child with previously unrecognized sickle cell anemia, post-traumatic hyphema, thrombosis in trabecular mashwork and consecutive acute glaucoma showed positive results. Thirteen year-old boy, son of African father and Caucasian mother, was admitted to hospital, with symptoms of acute glaucoma and partial hyphema after right eye trauma. Visual acuity of affected eye was 0.5 and intraocular pressure (IOP) 46 mm Hg. Despite a common therapy three days later clinical condition of patient's right eye was getting worst. Visual acuity was only hand motion (HM) and IOP 53 mmHg. At this point rose suspicion of sickle cell disease (SCD) and decision about injecting t-PA (20 microg) into anterior chamber was made. Cytological examination of aqueous humor revealed 10% sickled erythrocytes. Hemoglobin electrophoresis discovered hemoglobin S so that diagnosis of SCD was confirmed. Intraocular application of t-PA showed excellent results in post-traumatic hyphema with trabecular mashwork thrombosis in the patient with sickle cell anemia. Two-years follow up confirmed permanent normalisation of IOP and visual acuity. Successful outcome with anterior chamber paracentesis and intracameral injection of t-PA is promising novel approach, which we recommend in treatment of post-traumatic hyphema in SCD. 相似文献
57.
Application of ITS sequence analysis, RAPD and AFLP fingerprinting in characterising the yeast genus Fellomyces 总被引:1,自引:0,他引:1
Three molecular techniques, ITS sequence analysis, random amplified polymorphic DNA (RAPD) and amplified fragment length polymorphism (AFLP) were used to study phylogenetic and genotypic relationships among strains of the genus Fellomyces. In the analyses were included strains isolated predominantly from epiphytic lichens collected in Indonesia, China and Mexico. The polyphasic approach indicated that the Fellomyces isolates are genotypically heterogeneous and that lichens represent a specific environment for selection of large number of the sterigmatoconidia producing species. The phylogenetic and genotypic analysis confirmed the existence of 11 currently accepted Fellomyces species and indicated that several species may be the new representatives of the genus. The RAPD and AFLP analyses demonstrated a higher potential in distinguishing the Fellomyces strains than the ITS regions. Since the sequence analysis showed low or no divergence among several strains, both RAPD and AFLP fingerprinting indicated that the strains may be discriminated at the species level. 相似文献
58.
Caroline Brosy Ksenija Zaninovic Andreas Matzarakis 《International journal of biometeorology》2014,58(6):1369-1381
Tourism is one of the most important economic sectors in Croatia. The Adriatic coast is a popular travel destination for tourists, especially during the summer months. During their activities, tourists are affected by atmospheric conditions and therefore by weather and climate. Therefore, it is important to have reliable information about thermal conditions as well as their impacts on human beings. Here, the climate tourism potential of Croatia is presented and quantified on the basis of three selected stations in different climatic regions. The physiologically equivalent temperature is used for analysis as well as other climatic parameters relevant for tourism and recreation. The results already point to hot conditions for outdoor activities in summer during afternoons, especially along the coast but also for continental regions, resulting in a reduction of the climate tourism potential. In the future, this trend looks set to increase, possibly leading to a changing tourism sector in Croatia requiring adaptation and new strategies. 相似文献
59.
K Radotić C Roduit J Simonović P Hornitschek C Fankhauser D Mutavdžić G Steinbach G Dietler S Kasas 《Biophysical journal》2012,103(3):386-394
Cell-wall mechanical properties play a key role in the growth and the protection of plants. However, little is known about genuine wall mechanical properties and their growth-related dynamics at subcellular resolution and in living cells. Here, we used atomic force microscopy (AFM) stiffness tomography to explore stiffness distribution in the cell wall of suspension-cultured Arabidopsis thaliana as a model of primary, growing cell wall. For the first time that we know of, this new imaging technique was performed on living single cells of a higher plant, permitting monitoring of the stiffness distribution in cell-wall layers as a function of the depth and its evolution during the different growth phases. The mechanical measurements were correlated with changes in the composition of the cell wall, which were revealed by Fourier-transform infrared (FTIR) spectroscopy. In the beginning and end of cell growth, the average stiffness of the cell wall was low and the wall was mechanically homogenous, whereas in the exponential growth phase, the average wall stiffness increased, with increasing heterogeneity. In this phase, the difference between the superficial and deep wall stiffness was highest. FTIR spectra revealed a relative increase in the polysaccharide/lignin content. 相似文献
60.
Raimundo N Ahtinen J Fumić K Barić I Remes AM Renkonen R Lapatto R Suomalainen A 《Biochimica et biophysica acta》2008,1782(5):287-294
Defects of the oxidative ATP production pathway lead to an amazing variety of disease phenotypes, ranging from childhood encephalomyopathies to hereditary tumor formation. A key enzyme of tricarboxylic cycle, fumarate hydratase (FH), is involved in encephalopathies, but also in leiomyoma formation, and occasionally also in various types of cancer. MELAS (mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes) and NARP (neuropathy ataxia retinitis pigmentosa) are progressive neurological disorders, caused by mitochondrial DNA mutations and respiratory chain (RC) deficiency. These diseases lead to disability and premature death, but not to tumorigenesis. We studied the cellular consequences of FH and RC deficiencies, aiming to identify general responses to energy metabolism defect and those specific for FH-deficiency, suggestively connected to tumorigenesis. Unlike in RC deficiency, the FH-deficient diploid human fibroblasts showed no signs of oxidative stress, but had a reduced redox state with high glutathione levels. The cytoplasmic FH isoform, previously described, but with an unknown function, was completely lacking in all FH-deficient lines. Fumarate was increased in two of our FH-lines, but accumulation of HIF-1alpha was not detected. Glycolysis was induced in both MELAS and in FH-deficiency. Accumulation of fumarate in primary fibroblasts did not activate a hypoxia response, suggesting that hypoxia activation due to fumarate accumulation may be a tissue-specific response. The lack of cytoplasmic form of FH and the reduced redox environment were typical for all FH-mutant lines, and their role in FH-related tumorigenesis requires further attention. 相似文献