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排序方式: 共有782条查询结果,搜索用时 15 毫秒
1.
ngela P. de Mattos Tereza C.M. Ribeiro Patrícia S.A. Mendes Sandra S. Valois Carlos M.C. Mendes Hugo C. Ribeiro Jr 《Nutrition Research》2009,29(7):462-469
Although previous studies have shown successful treatment of persistent diarrhea (PD) with the use of yogurt-based diets, some recent ones speculate the need of special formulas for the nutritional management of PD complicated cases. In the present study, we tested the hypothesis that the consumption of 3 lactose-free diets, with different degrees of complexity, is associated with lower stool output and shorter duration of diarrhea when compared with the use of a yogurt-based one on the nutritional management of PD. A total of 154 male infants, aged between 1 and 30 months, with PD and with or without dehydration, were randomly assigned to 1 of 4 treatment groups. Throughout the study, the patients were placed in a metabolic unit; their body weights and intakes of oral rehydration solution, water, and formula diets, in addition to outputs of stool, urine, and vomit, were measured and recorded at 24-hour intervals. Four different diets were used in this study: diet 1, yogurt-based formula; diet 2, soy-based formula; diet 3, hydrolyzed protein-based formula; and diet 4, amino acid–based formula. Throughout the study, only these formula diets were fed to the children. The data showed that children fed the yogurt-based diet (diet 1) or the amino acid–based diet (diet 4) had a significant reduction in stool output and in the duration of diarrhea. The use of an inexpensive and worldwide-available yogurt-based diet is recommended as the first choice for the nutritional management of mild to moderate PD. For the few complicated PD cases, when available, a more complex amino acid–based diet should be reserved for the nutritional management of these unresponsive and severe presentations. Soy-based or casein-based diets do not offer any specific advantage or benefits and do not seem to have a place in the management of PD. 相似文献
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Breast cancer micrometastases: Different interactions of carcinoma cells with normal and cancer patients' bone marrow stromata 总被引:6,自引:1,他引:6
Nicola MH Bizon R Machado JJ Sollero T Rodarte RS Nobre JS Magalhães MM Takiya CM Borojevic R 《Clinical & experimental metastasis》2003,20(5):471-479
The apparently dormant breast cancer micrometastases in haemopoietic marrow are correlated with distant metastatic carcinoma
dissemination. We studied in vitro interactions of carcinoma cells with adjacent stromata, using connective tissue cell cultures from breast and bone marrow
samples of normal donors, comparing them to the pericancerous breast tissue and bone marrows of 12 selected patients with
invasive breast carcinomas. Cancer cells were detected by immunocytochemistry and RT-PCR in all the bone marrows and in most
blood samples of the studied patients. We monitored the growth and interaction of carcinoma MCF-7 cells with the stromata.
The normal breast stroma sustained typical massive cancer growth. The pericancerous breast stroma induced the invasive mesenchymal
pattern of growth. Normal bone marrow stroma induced the same conversion and was highly adhesive, retaining the cells in the
stroma, but carcinoma patients' bone marrow stromata underwent low adhesive interactions with cancer cells, releasing them
potentially into the circulation. The semi-quantitative RT-PCR indicated an enhanced expression of the hepatocyte growth factor
and its receptor c-met in breast and bone marrow stromata of cancer patients. The input of cancer cells into the normal bone marrow may induce modifications
of the local microenvironment, favourable for growth and release of carcinoma cells into the systemic circulation, which correlate
with the poor prognosis of patients with bone marrow micrometastases.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Two paralogous mitochondrial malate dehydrogenase 2 (Mdh2) genes of Xenopus laevis have been cloned and sequenced, revealing 95% identity. Fluorescence in-situ hybridization (FISH) combined with tyramide amplification discriminates both genes; Mdh2a was localized into chromosome q3
and Mdh2b into chromosome q8. One kb cDNA probes detect both genes with 85% accuracy. The remaining signals were on the paralogous
counterpart. Introns interrupt coding sequences at the same nucleotide as defined for mouse. Restriction polymorphism has
been detected in the first intron of Mdh2a, while the individual variability in intron 6 of Mdh2b gene is represented by an
insertion of incomplete retrotransposon L1Xl. Rates of nucleotide substitutions indicate that both genes are under similar
evolutionary constraints. X. laevis Mdh2 genes can be used as markers for physical mapping and linkage analysis. 相似文献
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Anna Veverkov Dalibor Preisler Mariia Zimina Tereza Koutov Petr Harcuba Milo Jane
ek Josef Strský 《Materials》2021,14(2)
Low-alloyed zirconium alloys are widely used in nuclear applications due to their low neutron absorption cross-section. These alloys, however, suffer from limited strength. Well-established guidelines for the development of Ti alloys were applied to design new two-phase ternary Zr alloys with improved mechanical properties. Zr-4Sn-4Nb and Zr-8Sn-4Nb alloys have been manufactured by vacuum arc melting, thermo-mechanically processed by annealing, forging, and aging to various microstructural conditions and thoroughly characterized. Detailed Scanning electron microscopy (SEM) analysis showed that the microstructural response of the alloys is rather similar to alpha + beta Ti alloys. Duplex microstructure containing primary alpha phase particles surrounded by lamellar alpha + beta microstructure can be achieved by thermal processing. Mechanical properties strongly depend on the previous treatment. Ultimate tensile strength exceeding 700 MPa was achieved exceeding the strength of commercial Zr alloys for nuclear applications by more than 50%. Such an improvement in strength more than compensates for the increased neutron absorption cross-section. This study aims to exploit the potential of alpha + beta Zr alloys for nuclear applications. 相似文献
9.
Tereza Cristina Cardoso Camila Silva-Frade Cilene Vidovix Táparo Lucas Hidenori Okamura Eduardo Furtado Flores 《Molecular and cellular probes》2013,27(5-6):237-242
The objective of this study was to optimize an internal control to improve SYBR-Green-based qPCR to amplify/detect the BoHV-5 US9 gene in bovine embryos produced in vitro and experimentally exposed to the virus. We designed an SYBR-Green-based binding assay that is quick to perform, reliable, easily optimized and compares well with the published assay. Herein we demonstrated its general applicability to detect BoHV-5 US9 gene in bovine embryos produced in vitro experimentally exposed to BoHV-5. In order to validate the assay, three different reference genes were tested; and the histone 2a gene was shown to be the most adequate for normalizing the qPCR reaction, by considering melting and standard curves (p < 0.05). On the other hand, no differences were found in the development of bovine embryos in vitro whether they were exposed to BoHV-5 reference and field strains comparing to unexposed embryos. The developed qPCR assay may have important field applications as it provides an accurate BoHV-5 US9 gene detection using a proven reference gene and is considerably less expensive than the TaqMan qPCR currently employed in sanitary programs. 相似文献
10.
Clarissa Campolina De Sá Mattosinho Anna Tereza M.S. Moura Gabriela Oigman Sima E. Ferman Nathália Grigorovski 《Pediatric hematology and oncology》2019,36(2):55-72
Retinoblastoma (RB) is the most common intraocular tumor of childhood. In low income countries, Time to diagnosis (TTD: interval between first symptom and diagnosis) has been associated with extraocular disease, metastasis and mortality. However, the relationship between TTD and prognosis is complex and not simply a linear correlation, particularly if TTD is <6?months. This systematic review aims to identify studies reporting TTD of retinoblastoma in Latin America, highlighting factors affecting TTD, alongside proposals and initiatives to obtain shorter intervals. The review also aims to discuss the methodology linked to cancer pathways studies. The study respected PRISMA recommendations, was registered on Prospero, an international database for systematic review registries under number CRD42017076777. MEDLINE/PUBMED, LILACS and SCIELO databases were searched. Studies from Latin America and the Caribbean, published between 1997 and 2017, reporting TTD and age at diagnosis of patients with retinoblastoma were selected. Nine studies were selected, concerning 1560 patients from Argentina, Brazil, Chile, Honduras, Mexico and Peru. The median TTD ranged from 3 to 5?months and the median age at diagnosis ranged from 16.5 to 22.2?months. A prolonged TTD was observed and was associated to damaging results on retinoblastoma outcomes, particularly increasing extraocular disease, and mortality rates. Methodological heterogeneity was observed and reiterates the importance of standardization of TTD studies, allowing more reliable comparisons and greater knowledge about retinoblastoma pathways before diagnosis. Reports on successful initiatives against delayed diagnosis were scarce, emphasizing a need for further studies. 相似文献