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排序方式: 共有1871条查询结果,搜索用时 9 毫秒
31.
Garijo P Santamaría P López R Sanz S Olarte C Gutiérrez AR 《International journal of food microbiology》2008,125(2):141-145
This research studies the presence of microorganisms of enological interest (yeasts, bacteria and molds) and their evolution in the air of a wine cellar. The samples were taken throughout the winemaking campaign (September-December) in a winery of the D.O.Ca. Rioja, Spain. They were collected using an airIDEAL atmosphere sampler from Biomerieux. For the isolation, specific selective media were used for each group of microorganisms. The results obtained indicate that the presence in the winery air of the various different microorganisms studied is directly related to the winemaking processes that are taking place in the winery. Thus, the number of molds present decreases once grapes have ceased to be brought into the winery. The maximum number of yeasts in the air is found when all the vats in the cellar are fermenting, while the lactic bacteria are not detected until the first malolactic fermentation begins. The species of yeasts and molds identified are also related to the winemaking processes. The coincidence of strains of Saccharomyces cerevisiae among those present in the vats during alcoholic fermentation and those isolated from the air, confirms the role of the latter as a transmitter of microorganisms. 相似文献
32.
González-Martín I González-Pérez C Hernández-Méndez J Alvarez-García N 《Meat science》2003,65(2):713-719
A near infrared spectrometer equipped with a standard 1210/210 bundle remote reflectance fibre-optic probe, with a 5×5 cm quartz window, was used for the determination of fatty acids in the subcutaneous fat of Iberian pigs. A comparative study was made of the determination of fatty acids (C14:0, C16:0, C18:0, C18:1, C18:2, C18:3, C20: 1, Σpolyunsaturated, Σmonounsaturated and Σsaturated) in samples of subcutaneous fat from Iberian pigs by direct application of the fibre-optic probe on samples of whole subcutaneous fat and with cam-lock cups, assessing extracts of total lipids with diethyl ether. The regression method employed was modified partial least squares (MPLS). Calibration of 157 samples, using the fibre optic probe, allowed determination of fatty acids in the following ranges: C14:0 (0.78-1.77), C16:0 (15.87-29.74), C18:0 (4.61-15.90), C18:1 (43.50-61.27), C18:2 (2.03-13.94), C18:3 (0.13-1.14), C20:1 (0.45-2.32), Σpolyunsaturated (2.31-14.82), Σmonounsaturated (47.37-65.62), Σsaturated (22.09-47.31), with corrected standard errors of prediction SEP(C) of 0.093, 0.56, 0.67, 0.94, 0.42, 0.10, 0.20, 0.46, 0.94, 0.83, respectively. The robustness of the method using the fibre-optic probe was tested in a slaughterhouse using 23 samples for external validation, giving multiple correlation coefficients (RSQ) for C14:0, C16:0, C18:0, C18:1, C18:2, C18:3 C20:1, Σpolyunsaturated, Σmonounsaturated, Σsaturated acids of 0.72, 0.94, 0.72, 0.79, 0.88, 0.55, 0.17, 0.88, 0.74, and 0.90, respectively, and a corrected standard error of prediction [SEP(C)] for these acids (%) of 0.11, 0.60, 0.84, 1.20, 0.77, 0.11, 0.30, 0.76, 1.21, and 1.18, respectively. 相似文献
33.
Blanco-Rodríguez J Martínez-García C Porras A 《Reproduction (Cambridge, England)》2003,126(5):661-668
In the seminiferous epithelium, both DNA synthesis and apoptosis occur at equivalent stages in various species, with apoptosis taking place mainly at the same stages as DNA replication in the second, third and fourth spermatogonial generations. As preservation of the cellular associations found at these stages may have some functional significance, it is important to determine whether there is a correlation between these cellular events. In this study, pairs of immunoperoxidase-stained adjacent testis sections from rats, mice, rabbits and cats in which either bromodeoxyuridine incorporated into the newly synthesized DNA strand (BrdU labelling) or DNA 3' end labelling of the apoptotic DNA fragments (TUNEL assay) were detected were compared. In addition, both events were analysed in double-labelled sections. These two methods revealed a clear correlation between the occurrence of DNA replication in the second to fourth generations of spermatogonia and most physiological apoptosis taking place in both spermatogonia and spermatocytes in the three different mammalian orders (Rodentia, Lagomorpha and Carnivora). This correlation may result from the synchronization of mitotic spermatogonial and meiotic spermatocyte cell cycle checkpoints operating at these stages. 相似文献
34.
n-Alkane content of intramuscular lipids (Biceps femoris muscle) of the Iberian pig have been determined. Thirty-four pigs, divided into four groups, based in the feeding system (Montanera, fed on acorns and pasture; and Pienso, fed on a concentrate feed) and in the genotype (Iberian pure pigs; and Iberian crossbred with Duroc 50%) were studied. n-Alkane content of intramuscular lipids has not been affected by neither crossbreeding nor feeding, although the analysis of feeds administered to the pigs showed greater n-alkane values in pasture (consumed by animals in montanera), than in acorns and concentrate feed. 相似文献
35.
36.
The Mig1p repressor from the food yeast Candida utilis has been isolated using a homologous PCR hybridization probe. This probe was amplified with two sets of degenerate primers designed on the basis of highly conserved motifs in the DNA-binding region (zinc-finger domain) from yeast Mig1p and fungi CreA repressors. The cloned gene was sequenced and found to encode a polypeptide of 345 amino acids which shows significant identity with other yeast and fungus repressors in the DNA-binding domain and also with the yeast Mig1 proteins in the C-terminal region (effector domain). The MIG1 repressor gene from C. utilis was able to complement functionally the mig1 mutation of S. cerevisiae. The sequence presented here has been deposited in the EMBL data library under Accession No. AJ277830. 相似文献
37.
Tomato industries yield a high amount of by-products mainly tomato peel and seeds. Since tomato peel is rich in lycopene, the direct addition of peel to food products could be a way to use this by-product to obtain a new products enriched in lycopene. This work describes experiments performed to develop dry fermented sausages (salchichón) containing this carotene. 0%, 0.6%, 0.9% and 1.2% (w/w) of dry tomato peel was added to the meat mixture used in sausage manufacture. A slight losts of lycopene was detected after 21 days ripening, however, levels remained between 0.26 and 0.58 mg of lycopene/100 g of sausage. The sensory and textural properties and overall acceptability of all sausages were good, indicating that tomato peel could be added to dry fermented sausages to produce a meat product enriched in lycopene. 相似文献
38.
Miguel M Dávalos A Manso MA de la Peña G Lasunción MA López-Fandiño R 《Molecular nutrition & food research》2008,52(12):1507-1513
This paper examines the in vitro transepithelial transport of antihypertensive peptides derived from egg proteins using Caco-2 cell monolayers. Ovokinin (FRADHPFL) was absorbed intact through the Caco-2 cell epithelium, although it was also susceptible to the action of brush-border aminopeptidases that yielded shorter fragments prior to their transport. The tripeptide YPI was resistant to cellular peptidases and transported through the monolayer, what suggests that the reduction in systemic blood pressure caused by this peptide may be mediated by effects at tissue level. Its pathway for transepithelial absorption was examined using inhibitors of the different mechanisms for oligopeptide transport in the intestinal tract. The main route involved in the transepithelial flux of YPI is probably the peptide H(+)-coupled transporter PepT1. These results highlight the potential of antihypertensive peptides to be used in the formulation of functional foods. 相似文献
39.
van Drooge BL Grimalt JO Camarero L Catalan J Stuchlík E Torres García CJ 《Environmental science & technology》2004,38(13):3525-3532
Atmospheric samples from two European high-mountain areas showed similar composition of semivolatile organochlorine compounds (SOC), such as polychlorobiphenyls (PCBs), DDTs, endosulfans, hexachlorobenzene (HCB), and hexachlorocyclohexanes (HCHs). Nearly all compounds were predominantly found in the gas phase and only the less volatile such as some PCBs (e.g., 149, 118, 153, 138, and 180) were found in higher abundance in the particulate phase. HCB, 49-85 pg m(-3), is the dominant SOC. This compound is only found in the gas phase exhibiting uniform concentrations irrespective of season and air mass origin. SOC of present use, like HCHs and endosulfans, were found in higher concentrations in the warm periods, 32-46 and 4-10 pg m(-3) in the gas + particulate phases, respectively, reflecting their seasonal pattern of use in many European countries. PCB and 4,4'-DDE, 39-42 and 4-6 pg m(-3) in the gas + particulate phases, respectively, also showed a seasonal trend despite neither the former nor the precursor of the latter (4,4'-DDT) being manufactured with their use drastically restricted since the 1980s. The seasonal differences are mainly due to a higher occurrence of air masses with strong continental inputs in the warm than in the cold periods. In this respect, samples whose air masses traveled at the high troposphere (backward air mass trajectories >6000 m) have been observed to carry considerably smaller PCB and 4,4'-DDE loads (9.3 +/- 2.8 and 0.4 +/- 0.05 pg m(-3), respectively) than overall average. 相似文献
40.
Cellular localization and changes in expression of prolactin receptor isoforms in sheep ovary throughout the estrous cycle 总被引:3,自引:0,他引:3
Picazo RA García Ruiz JP Santiago Moreno J González de Bulnes A Muñoz J Silván G Lorenzo PL Illera JC 《Reproduction (Cambridge, England)》2004,128(5):545-553
The actions of prolactin (PRL) on target cells depend on the type of prolactin receptor (PRLr) predominantly expressed, particularly whether the long PRLr isoform is expressed. The aims of this study were to determine the cellular localization and the changes in expression of long and short PRLr isoforms in sheep ovary throughout the estrous cycle. Long and short PRLrs were localized mostly in the same ovarian cells. Maximum signal intensity, particularly for long PRLrs, was found in stromal cells surrounding primordial and primary follicles, and, for both PRLrs, in granulosa cells of preantral follicles and in luteal cells. Moderate signal intensity for PRLrs was found in theca cells of preantral to ovulatory follicles, and in granulosa cells of antral follicles up to the gonadotropin-dependent stage. Decreasing immunoreactivity to PRLrs was found in granulosa cells of gonadotropin-dependent to ovulatory follicles. For long PRLrs in particular, no signal was found in mural granulosa cells of gonadotropin-dependent follicles; for both isoforms, no signal was found in most granulosa cells of ovulatory follicles. In primordial to gonadotropin-dependent follicles, cellular localization of PRLr was similar on days 0, 10 and 15 of the cycle. Oocytes consistently showed positive immunostaining for PRLrs. Comparative RT-PCR analysis of long and short PRLr expression showed that the short isoform is evenly expressed throughout the estrous cycle, whereas the expression of the long form increases at the time of estrus and decreases at mid-luteal phase and at the onset of the follicular phase. Expression of long PRLrs was greater than that of short PRLrs on day 0 of cycle; expression of both isoforms was similar on day 10 and on day 15, long PRLrs expression was lower than that of short PRLrs. Our results indicate that in sheep ovary, the maximum responsiveness to PRL might occur during the preovulatory phase of the estrous cycle. 相似文献