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71.
72.
L. Del Senno F. Conconi P.F.R. Little R. Williamson 《Biochemical and biophysical research communications》1979,91(2):548-553
The map of restriction sites including and surrounding the δ- and β-globin genes has been established for three Ferrara β°-thalassaemic subjects. The fragments obtained using nine restriction enzymes do not show any differences from normal DNA. Among others, restriction enzymes giving short fragments at the 5′ and 3′ ends of the β-globin structural gene have been employed. The results obtained for the thalassaemic DNA are identical to those for control DNA, thus excluding the presence of extensive deletions in or adjacent to the coding regions of the β-globin gene in Ferrara β°-thalassaemia. 相似文献
73.
Abstract. This study was designed to define some biological aspects of cell suspensions, obtained by mechanical or enzymatic disaggregations, and to verify whether single cell suspensions are representative of original solid tumours. The study was performed on a series of 25 human solid tumours including breast carcinoma, ovarian carcinoma and malignant melanoma. A higher cell viability and a loss of aneuploid subpopulations, or a lower fraction of aneuploid cells, were observed in enzymatically-released samples than in samples obtained by the mechanical procedure. Moreover, the proliferative activity, which was generally similar for the cell suspensions obtained by the two disaggregation procedures, was always markedly lower in the cell suspensions than in solid samples from the same tumour. In conclusion, the results from this study indicate that many changes, such as selective release of cell populations from the tumour matrix, damage and destruction of aneuploid and proliferating cells can be induced to various extents by different disaggregation procedures. 相似文献
74.
Juan Del Coso Javier Portillo Gloria Muñoz Javier Abián-Vicén Cristina Gonzalez-Millán Jesús Muñoz-Guerra 《Amino acids》2013,44(6):1511-1519
The aim of this study was to determine the effects of a caffeine-containing energy drink on physical performance during a rugby sevens competition. A second purpose was to investigate the post-competition urinary caffeine concentration derived from the energy drink intake. On two non-consecutive days of a friendly tournament, 16 women from the Spanish National rugby sevens Team (mean age and body mass = 23 ± 2 years and 66 ± 7 kg) ingested 3 mg of caffeine per kg of body mass in the form of an energy drink (Fure®, ProEnergetics) or the same drink without caffeine (placebo). After 60 min for caffeine absorption, participants performed a 15-s maximal jump test, a 6 × 30 m sprint test, and then played three rugby sevens games against another national team. Individual running pace and instantaneous speed during the games were assessed using global positioning satellite (GPS) devices. Urine samples were obtained pre and post-competition. In comparison to the placebo, the ingestion of the energy drink increased muscle power output during the jump series (23.5 ± 10.1 vs. 25.6 ± 11.8 kW, P = 0.05), running pace during the games (87.5 ± 8.3 vs. 95.4 ± 12.7 m/min, P < 0.05), and pace at sprint velocity (4.6 ± 3.3 vs. 6.1 ± 3.4 m/min, P < 0.05). However, the energy drink did not affect maximal running speed during the repeated sprint test (25.0 ± 1.5 vs. 25.0 ± 1.7 km/h). The ingestion of the energy drink resulted in a higher post-competition urine caffeine concentration than the placebo (3.3 ± 0.7 vs. 0.2 ± 0.1 μg/mL; P < 0.05). In summary, 3 mg/kg of caffeine in the form of a commercially available energy drink considerably enhanced physical performance during a women’s rugby sevens competition. 相似文献
75.
Experiments were designed to test the hypotheses that ovarian follicular response to superstimulatory treatment initiated during Wave 1 is equivalent to that of Wave 2, and recovery rate and quality of ova embryos derived from follicles of Wave 1 are equivalent to those derived from follicles of Wave 2. In a preliminary experiment (Experiment 1), heifers were given Folltropin-V (20 mg NIH-FSH-P1, im, bid for 5 d) beginning the day after emergence of the first (n=10) or second (n=10) follicular wave of the estrous cycle, equivalent to approximately Day 1 and Day 10, respectively (Day 0=ovulation). Luteolysis was induced with cloprostenol (500 mug im, bid) on the fourth day of treatment. Fewer (P<0.05) ovulations per heifer were induced in the Wave 1 group than in the Wave 2 group (4.6+/-1.0 vs 9.1+/-1.3). However, the interval from wave emergence to initiation of treatment was found, in retrospect, to have been longer (P<0.05) in the Wave 1 group, i.e., treatment was initiated relatively later with respect to wave emergence. Experiment 2 was designed to correct this disparity and to initiate the same treatment protocol on the day of wave emergence rather than the day after (n=21 per Wave group). There was no difference between Wave 1 and Wave 2 groups in the interval from wave emergence to initiation of treatment (0.4+/-0.1 d), the number of ovulations detected by ultrasonography (6.6+/-1.0 vs 8.2+/-1.7), the number of CL detected at slaughter (6.5+/-0.9 vs 8.1+/-1.8), the total number of ova embryos recovered (5.2+/-0.7 vs 5.1+/-0.8), or the number of fertilized embryos collected (2.8+/-0.6 vs 3.0+/-0.6). In addition, there was no difference between groups in the proportion of heifers that ovulated in either experiment; collectively, luteolysis and ovulation was induced in 58 of 60 heifers. The results supported the general hypothesis that follicles and oocytes of the first and second follicular waves are equivalent in the response to superstimulatory treatment. Regardless of which follicular wave, initiation of treatment near the time of wave emergence appears critical for maximal superovulatory response. Because of the consistency in the time of emergence of Wave 1 (day of ovulation) and equivalence in superovulatory response, use of Wave 1 rather than subsequent follicular waves may be more convenient and time-sparing in superovulation programs; the day of estrus (day before ovulation) may be used as a consistent point of reference for the start of treatment. 相似文献
76.
Barbara Lazzari Andrea Caprera Alessandro Cestaro Ivan Merelli Marcello Del Corvo Paolo Fontana Luciano Milanesi Riccardo Velasco Alessandra Stella 《BMC plant biology》2009,9(1):82
Background
Two complete genome sequences are available for Vitis vinifera Pinot noir. Based on the sequence and gene predictions produced by the IASMA, we performed an in silico detection of putative microRNA genes and of their targets, and collected the most reliable microRNA predictions in a web database. The application is available at . 相似文献77.
Falchetti A Di Stefano M Marini F Del Monte F Gozzini A Masi L Tanini A Amedei A Carossino A Isaia G Brandi ML 《Arthritis research & therapy》2005,7(6):R1289-R1295
Mutations of the p62/Sequestosome 1 gene (p62/SQSTM1) account for both sporadic and familial forms of Paget's disease of bone (PDB). We originally described a methionine-->valine substitution at codon 404 (M404V) of exon 8, in the ubiquitin protein-binding domain of p62/SQSTM1 gene in an Italian PDB patient. The collection of data from the patient's pedigree provided evidence for a familial form of PDB. Extension of the genetic analysis to other relatives in this family demonstrated segregation of the M404V mutation with the polyostotic PDB phenotype and provided the identification of six asymptomatic gene carriers. DNA for mutational analysis of the exon 8 coding sequence was obtained from 22 subjects, 4 PDB patients and 18 clinically unaffected members. Of the five clinically ascertained affected members of the family, four possessed the M404V mutation and exhibited the polyostotic form of PDB, except one patient with a single X-ray-assessed skeletal localization and one with a polyostotic disease who had died several years before the DNA analysis. By both reconstitution and mutational analysis of the pedigree, six unaffected subjects were shown to bear the M404V mutation, representing potential asymptomatic gene carriers whose circulating levels of alkaline phosphatase were recently assessed as still within the normal range. Taken together, these results support a genotype-phenotype correlation between the M404V mutation in the p62/SQSTM1 gene and a polyostotic form of PDB in this family. The high penetrance of the PDB trait in this family together with the study of the asymptomatic gene carriers will allow us to confirm the proposed genotype-phenotype correlation and to evaluate the potential use of mutational analysis of the p62/SQSTM1 gene in the early detection of relatives at risk for PDB. 相似文献
78.
D'Elios MM Amedei A Benagiano M Azzurri A Del Prete G 《FEMS immunology and medical microbiology》2005,44(2):113-119
Helicobacter pylori infection is the major cause of gastroduodenal pathologies, but only a minority of infected patients develop chronic and life threatening diseases, as peptic ulcer, gastric cancer, B-cell lymphoma, or autoimmune gastritis. The type of host immune response against H. pylori is crucial for the outcome of the infection. A predominant H. pylori-specific Th1 response, characterized by high IFN-gamma, TNF-alpha, and IL-12 production associates with peptic ulcer, whereas combined secretion of both Th1 and Th2 cytokines are present in uncomplicated gastritis. Gastric T cells from MALT lymphoma exhibit abnormal help for autologous B-cell proliferation and reduced perforin- and Fas-Fas ligand-mediated killing of B cells. In H. pylori-infected patients with autoimmune gastritis cytolytic T cells infiltrating the gastric mucosa cross-recognize different epitopes of H. pylori proteins and H+K+ ATPase autoantigen. These data suggest that peptic ulcer can be regarded as a Th1-driven immunopathological response to some H. pylori antigens, whereas deregulated and exhaustive H. pylori-induced T cell-dependent B-cell activation can support the onset of low-grade B-cell lymphoma. Alternatively, H. pylori infection may lead in some individuals to gastric autoimmunity via molecular mimicry. 相似文献
79.
Stomatal response to air humidity and its relation to stomatal density in a wide range of warm climate species 总被引:1,自引:0,他引:1
Mabrouk A. El-Sharkawy James H. Cock Ana Del Pilar Hernandez 《Photosynthesis research》1985,7(2):137-149
The gas exchange of 19 widely different warm climate species was observed at different leaf to air vapour pressure deficits (VPD). In all species stomata tended to close as VPD increased resulting in a decrease in net photosynthesis. The absolute reduction in leaf conductance per unit increase in VPD was greatest in those species which had a large leaf conductance at low VPDs. This would be expected even if stomata of all species were equally sensitive. However the percentage reduction in net photosynthesis (used as a measure of the relative sensitivity of stomata of the different species) was also closely related to the maximal conductance at low VPD. Similarily the relative sensitivity of stomata to changes in VPD was closely related to the weighted stomatal density or crowding index.The hypothesis is presented that stomatal closure at different VPDs is related to peristomatal evaporation coupled with a high resistance between the epidermis and the mesophyll and low resistance between the stomatal apparatus and the epidermal cells. This hypothesis is consistent with the greater relative sensitivity of stomata on leaves with a high crowding index.The results and the hypothesis are discussed in the light of selection, for optimal productivity under differing conditions of relative humidity and soil water availablility, by observation of stomatal density and distribution on the two sides of the leaf.Visiting scientist, plant physiologist and research assitant of the Cassava Program 相似文献
80.
Centrin homologues in higher plants are prominently associated with the developing cell plate 总被引:3,自引:0,他引:3
A. J. Del Vecchio J. D. I. Harper K. C. Vaughn A. T. Baron J. L. Salisbury R. L. Overall 《Protoplasma》1997,196(3-4):224-234
Summary Centrin and calmodulin are members of the EF-hand calcium-binding superfamily of proteins. In this study we compared localisation and immunoblotting of centrin with calmodulin in several monocot (onion and wheat) and dicot (mung bean andArabidopsis) plants. We confirmed that an anti-calmodulin antibody recognised a 17 kDa protein in all species tested and localises to the cytoplasm, mitotic matrix and with microtubules of the preprophase band and phragmoplast. In contrast, immunoblotting using anti-centrin antibodies shows that plant centrins vary from 17 to 20 kDa. Immunofluorescence microscopy with anti-centrin antibodies revealed only weak centrin immunoreactivity in the cytoplasm, nucleus, nuclear envelope, phragmoplast and mitotic matrix in meristematic cells. There was a slightly more intense perinuclear labelling in large differentiating onion cells and between separating anaphase chromosomes. While centrin is known to localise to the mitotic spindle poles in animal and algal cells, there was no appreciable immunoreactivity at the spindle poles in higher plants. In contrast, there was an intense immunofluorescence signal with anti-centrin antibodies in the developing cell plate. Further characterisation of the cell plate labelling by immunogold electron microscopy shows centrin immunoreactivity was closely associated with vesicles in the cell plate. Our observations suggest that centrin may play a role in cell plate formation.Abbreviations BSA
bovine serum albumin
- MTs
microtubules
- MTOCs
microtubule organising centres
- PBS
phosphate buffered saline
- PBST
phosphate buffered saline with Tween-20 相似文献