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71.
72.
KI SOON RHEE ROBERT N. TERRELL MARIA QUINTANLL LA CARL VANDERZANT 《Journal of food science》1983,48(1):302-303
Two experiments were conducted to determine rancidity development in raw-refrigerated ground pork treated with different types and levels of chloride salts. In the first experiment, raw ground pork was inoculated with either a Moraxella or a Lactobacillus species. In the second experiment, samples were not inoculated. In both experiments, samples were treated with either NaCl, KCl, or MgCl2 at ionic strength of either 0.73 or 0.37 and stored at 5°C. Regardless of inoculation, in both experiments addition of any chloride salt increased (P < 0.05) TBA values over those values for controls (no added salt). Addition of NaCl resulted in the highest (P < 0.05) TBA values among inoculated samples, but these differences were not apparent for noninoculated samples. 相似文献
73.
CARMINDA DA CRUZ-LANDIM FÁBIO CAMARGO ABDALLA MARIA ALICE DA CRUZ-HÖFLING 《Biocell》2003,27(3):319-328
The spermatogenesis of Piaractus mesopotamicus was investigated under light and transmission electron microscopy. The specimens were captured from their natural environment (Rio Miranda and Rio Aquidauana, Pantanal Matogrossense, Brazil) during April and September. The results were compared with the spermatogenic data of specimens under captivity condition. In both conditions, P. mesopotamicus presented the typical spermatogenesis pattern of the teleost fishes, showing no significative differences. The spermatozoon was classified as type I, which has a globular head without acrosome, a short middle piece and a long tail constituted only by the flagellum. This type of spermatozoon is considered the basic type in fishes. 相似文献
74.
ELEONIDAS MOURA LIMA MARIANA FERREIRA LEAL MARÍLIA DE ARRUDA CARDOSO SMITH ROMMEL RODRÍGUEZ BURBANO PAULO PIMENTEL DE ASSUMPÇÃO MARIA JOSE BELLO JUAN ANTONIO REY FRANCINALDO FERREIRA DE LIMA CACILDA CASARTELLI 《Biocell》2008,32(3):237-243
Gastric cancer is one of the most common malignancies. DNA methylation is implicated in DNA mismatch repair genes deficiency. In the present study, we evaluated the methylation status of MLH1, MSH2, MSH6 and PMS2 in 20 diffuse- and 26 intestinal-type gastric cancer samples and 20 normal gastric mucosal of gastric cancer patients from Northern Brazil. We found that none of the nonneoplastic samples showed methylation of any gene promoter and 50% of gastric cancer samples showed at least one methylated gene promoter. Methylation frequencies of MLH1, MSH2, MSH6 and PMS2 promoter were 21.74%, 17.39%, 0% and 28.26% respectively in gastric cancer samples. MLH1 and PMS2 methylation were associated with neoplastic samples compared to nonneoplastic ones. PMS2 methylation was associated with diffuse- and intestinal-type cancer compared with normal controls. Intestinal-type cancer showed significant association with MLH1 methylation. Diffuse-type cancer was significantly associated with MSH2 methylation. Our findings show differential gene methylation in tumoral tissue, which allows us to conclude that methylation is associated with gastric carcinogenesis. Methylation of mismatch repair genes was associated with gastric carcinogenesis and may be a helpful tool for diagnosis, prognosis and therapies. However, MSH6 does not seem to be regulated by methylation in our samples. 相似文献
75.
DOMENICO MARIA CARRETTA MARINA DI DOMENICO ROBERTO LOVERO ROBERTO ARRIGONI ANGELIKA ELZBIETA WEGIERSKA MARIAROSARIA BOCCELLINO REA BALLINI IOANNIS ALEXANDROS CHARITOS LUIGI SANTACROCE 《Biocell》2022,46(8):1779-1788
The existence of an inflammatory process in the heart muscle, related to a progressive worsening of myocardial
function, different etiopathogenetic mechanisms concur and often overlap, thus making the diagnosis and the therapeutic
approach complex. As the COVID-19 pandemic progresses, the effects of the disease on the organ systems and in
particular on the cardiovascular system are becoming more and more profound. Cardiac involvement is a well-known
event with a high percentage of findings in the heart’s magnetic field, even in asymptomatic areas. There are
numerous uncertainties regarding their evolution, in the long and short term, due not only to a difficult to determine
the varied clinical expression and the rarely performed intramyocardial biopsy which additionally presents diagnostic
problems but also in part to different clinical prognosis. Today, the new SARS-CoV-2 virus that uses the angiotensin
converting enzyme 2 (ACE2) which is present at high levels in myocardial cells as its entrance it can create even
severe heart injury. The pathophysiology in all of these cases can involve multiple immune and non-immune
mechanisms within organs and vessels and can be occur in the clinical phases. Possible mechanisms of direct and
indirect myocardial infarction in patients with COVID-19 include additional lesion and oxygen-rich and generalized
inflammation response with myocardial immune hyperactivity (myocarditis). Therefore, these can occur through the
excessive release of cytokines, the presence of thrombocytopenia, endocrine damage, heart failure, arrhythmias and
more. Patients can show average signs of myocardial damage, and some develop spontaneous cardiac complications,
such as heart failure, arrhythmias and, rarely, rare cardiogenic disorders. Pathophysiology in all of these may involve
multiple mechanisms within the cytokine cephalic membrane, endocrine damage and thrombogenicity. The diagnosis
of this myocardial injuri is mainly based on the myocardial enzyme troponin. This viewpoint paper explains today’s
knowledge on viral myocarditis, in particular that from SARS-CoV-2 infection, if there is a connection with other
possible biomolecular pathogenetic factors that can influence its natural course. In fact, it is for this reason that the
pathogenetic mechanisms are analyzed and described. At the same time, its possible interaction with other parameters
that are documented risk factors for cardiovascular disease was examined. Although these biomolecular findings were
mainly related to necrotic parts of the myocardium, it is important to recognize that myocardial damage early for a
better approach and prognosis. 相似文献
76.
77.
78.
ELEMENTARY SCHOOL DIFFICULTIES OF LOW‐INCOME LATINO AND AFRICAN AMERICAN YOUTH: THE ROLE OF GEOGRAPHIC CONTEXT 下载免费PDF全文
Do the geographic contexts in which disadvantaged children are raised influence whether they have difficulties in elementary school? We address this question by estimating Cox proportional hazard models with instrumental variable measures of context, using data for 410 low‐income Latino and African American children who lived in Denver public housing before age six. The Denver Housing Authority's procedure for allocating families to dwellings mimics random assignment, thus offering an unusual natural experiment for measuring context effects isolated from geographic selection bias. We find that several socioeconomic and demographic contextual indicators are statistically and substantively important predictors of low‐income Latino and African American children's difficulties in elementary school, though sometimes in nonlinear and interactive ways. Generally, the hazard of being assigned to special education classes, suspended, or forced to repeat a grade is greater in neighborhoods with higher occupational prestige and percentages of immigrants and lower in those with higher percentages of African American residents. 相似文献
79.
IMEN SOUID ZEMNI HASSENE EVA SÁNCHEZ PALOMO MARIA SOLIDAD PÉREZ-COELLO ABDELWAHED GHORBEL 《Journal of food quality》2007,30(5):718-730
ABSTRACT
The aroma composition of the grape juice of Khamri, a native variety of Vitis vinifera grown in Tunisia, was investigated for the first time. A total of 27 free and 20 glycosidically bound compounds were identified by gas chromatography‐mass spectrometry. According to the obtained results, the aroma compounds were C6 alcohols, benzene compounds, terpenes, acids and norisoprenoids. On the basis of gas chromatography‐olfactometry, these compounds were grouped, according to volatiles exhibiting the identical odor quality, into 10 groups of the same character (aromatic series) as a way of establishing an aroma profile for the studied variety. The high glycosidically bound norisoprenoid concentrations and the absence of the bound form of the acids were a positive factor for the Khamri variety potential aroma.PRACTICAL APPLICATIONS
This article aimed on the identification of the unknown Tunisian grapevine varieties that are very well adapted to the arid conditions and that could have a good quality. The discovery of unknown autochthonous grapevine varieties with good aroma and pomological characteristics could be of great importance for the agriculture sector all over the world especially the arid regions.80.
Chemical Destruction of Aspergillus niger Conidiospores 总被引:1,自引:0,他引:1
SUMMARY: Destruction of A. niger conidiospores at 20°C (68°F) by 20 ppm NaClO and 20 ppm iodine as iodophor yielded D values of 0.61 min and 0.86, respectively at pH 3.0 and 1.31 and 2.04 min, respectively at pH 7.0. On the basis of mojar concentrations, iodine was slightly more effective than chlorine. A D value of 0.026 min was obtained with 4% NaOH at 60°C (140°F) indicating 4% NaOH at 60°C to be far more germicidal than 20 ppm of either halogen compound at 20°C. One per cent NaOH at 30°C resulted in an immediate and rapid release of amino acids presumably from the spore wall during the first 2 min of contact and a slower rate of release of RNA, with DNA released at the slowest rate. 相似文献