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排序方式: 共有5617条查询结果,搜索用时 15 毫秒
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Fabíola Azanha de Carvalho Amanda Aleixo Moreira André Luiz Martinez de Oliveira Fabio Yamashita 《应用聚合物科学杂志》2021,138(28):50667
Neat poly (lactic acid) (PLA) and PLA/cassava bagasse (CB) composites were used to produce seedling tubes by extrusion and injection molding. The tubes were buried in simulated soil, and their biodegradation was investigated by weight loss, scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). After 180 days, the composites' biodegradation was higher than neat PLA material, and the higher the CB content, the higher the biodegradation, which caused fissures and voids in the material. The biodegradation of PLA/CB composites increased the phosphorus content in the soil after 180 days. Composites of PLA with CB, an abundant agro-industrial residue in Brazil, are promising because they can reduce the environmental impact due to CB's proper destination, and the composites' costs and biodegradation are faster than pure PLA material. Both the faster biodegradation of the tube and the higher P content are advantageous for seedling tubes. 相似文献
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Erika Aparecida Silveira Golnaz Vaseghi Annelisa Silva de Carvalho Santos Nathalie Kliemann Farzad Masoudkabir Matias Noll Noushin Mohammadifard Nizal Sarrafzadegan Cesar de Oliveira 《International journal of molecular sciences》2020,21(23)
The association between obesity, cancer and cardiovascular disease (CVD) has been demonstrated in animal and epidemiological studies. However, the specific role of visceral obesity on cancer and CVD remains unclear. Visceral adipose tissue (VAT) is a complex and metabolically active tissue, that can produce different adipokines and hormones, responsible for endocrine-metabolic comorbidities. This review explores the potential mechanisms related to VAT that may also be involved in cancer and CVD. In addition, we discuss the shared pharmacological treatments which may reduce the risk of both diseases. This review highlights that chronic inflammation, molecular aspects, metabolic syndrome, secretion of hormones and adiponectin associated to VAT may have synergistic effects and should be further studied in relation to cancer and CVD. Reductions in abdominal and visceral adiposity improve insulin sensitivity, lipid profile and cytokines, which consequently reduce the risk of CVD and some cancers. Several medications have shown to reduce visceral and/or subcutaneous fat. Further research is needed to investigate the pathophysiological mechanisms by which visceral obesity may cause both cancer and CVD. The role of visceral fat in cancer and CVD is an important area to advance. Public health policies to increase public awareness about VAT’s role and ways to manage or prevent it are needed. 相似文献
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MA Molina MJ Romero E Abril I Delgado RM Cano F Garrido JM de Pablos ML Garrido 《Canadian Metallurgical Quarterly》1994,39(4):253-256
INTRODUCTION: Heterozygous beta-thalassemia manifests hematologically with microcytosis, reduced red blood cell hemoglobin concentration and high hemoglobin A2 levels. Almost all molecular alterations are due to point mutations. We attempt to determinate the frequency of that mutations in the Oriental Andalusia Area, and its relationship with the hematological phenotype. PATIENTS AND METHODS: We have studied 45 heterozygous patients. DNA samples were amplified by PCR, using the printers CD7 and HI1. A 16 Kb fragment corresponding to beta globin gene was obtained and analyzed by Dot Blot assay and hybridized with allelic specific oligonucleotide (ASO) probes to detect the 6 more frequent mutations found in the South of Spain. RESULTS: Codon 39 nonsense mutation (31.1%) was the most frequent finding followed by IVS-1 NT 110 (26.7%). The relationship between hematological parameters and molecular mutations concluded that IVS-I NT 6 mutation developed a minimal anemia. DISCUSSION: From the practical point of view, this study indicates that we were able to detect more than 90% of heterozygous beta-tal. with 5 out of 6 ASO probes used in this work. Thus, our data also provides a further implication in prenatal diagnosis. 相似文献
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ML Martínez-Frías E Bermejo Sánchez E Rodríguez Pinilla A Villa 《Canadian Metallurgical Quarterly》1997,46(6):593-596
INTRODUCTION: Even though there are few epidemiological studies evaluating the birth weights of different groups of malformed babies with chromosomal abnormalities, it is widely known that infants with trisomy 18, and to a lesser degree those with trisomy 13 and other chromosomal alterations, have low birth weights. PATIENTS AND METHODS: In this study we present the analysis of the birth weights and gestational ages of a large sample of babies (23,155 malformed and a similar number of nonmalformed babies), separating the different groups of chromosomal anomalies and comparing the weight in the clinical groups of malformed infants. RESULTS: Most of the groups with chromosomal abnormalities present lower birth weights in comparison to the other groups. CONCLUSIONS: The results of our study support the conclusion that the relationship between chromosomal alterations and low birth weight is sufficiently important that such a low birth weight in children with minor or major anomalies should be considered as one more indication to perform chromosomal analysis. 相似文献
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C Diamond ML Huang DH Kedes C Speck GW Rankin D Ganem RW Coombs TM Rose JN Krieger L Corey 《Canadian Metallurgical Quarterly》1997,176(3):775-777
The prevalence of human herpesvirus 8 (HHV-8)/Kaposi's sarcoma (KS)-associated herpesvirus was investigated in the semen of 99 human immunodeficiency virus (HIV)-infected men (median CD4 cell count, 357/mm3) by use of a polymerase chain reaction (PCR) assay capable of detecting <10 copies of HHV-8 DNA. Of the subjects, 95 (96%) self-identified as men who have sex with men (MSM), and 3 had a history of clinical KS. Seminal cell specimens were negative for HHV-8 in 98 subjects. None of the 26 without KS (27.1% of 96 tested) who were seropositive for HHV-8 by IFA for latency-associated nuclear antigens had HHV-8 detected in their semen. The only subject with any evidence for seminal HHV-8 DNA was seropositive for HHV-8 and had active KS. HHV-8 was detected in 10 (10.4%) of 96 peripheral blood mononuclear cell specimens. The prevalence of HHV-8 DNA by PCR in semen of HIV-infected MSM without KS is low. 相似文献
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KJ Greenlund WH Giles NL Keenan JB Croft ML Casper D Matson-Koffman 《Canadian Metallurgical Quarterly》1998,7(9):1125-1133
We sought to examine the prevalence of self-reported multiple cardiovascular disease (CVD) risk factors (hypertension, high blood cholesterol, diabetes, overweight, and current smoking) among women in 1992 and 1995 in the United States using data from the Behavioral Risk Factor Surveillance System. In 1992, 37.5%, 34.4%, and 28.1% of women had zero, one, and two or more of the five risk factors, respectively. In 1995, the respective estimates were 35.5%, 34.3%, and 30%. In both years, the prevalence of two or more risk factors increased with age, decreased with educational level, was higher among black women (lowest among Hispanic women and women of other ethnic groups), and higher among women reporting cost as a barrier to healthcare. The percentage of women with two or more risk factors was higher in 1995 than in 1992 for 35 of 48 states, being statistically significant for 7 states. The percentage of women with at least two risk factors was not significantly lower in 1995 than in 1992 for any state. A higher percentage of women reported having multiple CVD risk factors in 1995 compared with 1992. A multifactorial approach to primary prevention and risk factor reduction should be encouraged to help reduce the prevalence and burden of CVD among women. 相似文献