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排序方式: 共有725条查询结果,搜索用时 15 毫秒
41.
KH Neppelenbroek RS Seó VM Urban S Silva LN Dovigo JH Jorge NH Campanha 《Oral diseases》2014,20(4):329-344
In healthy individuals, Candida species are considered commensal yeasts of the oral cavity. However, these microorganisms can also act as opportunist pathogens, particularly the so‐called non‐albicans Candida species that are increasingly recognized as important agents of human infection. Several surveys have documented increased rates of C. glabrata, C. tropicalis, C. guilliermondii, C. dubliniensis, C. parapsilosis, and C. krusei in local and systemic fungal infections. Some of these species are resistant to antifungal agents. Consequently, rapid and correct identification of species can play an important role in the management of candidiasis. Conventional methods for identification of Candida species are based on morphological and physiological attributes. However, accurate identification of all isolates from clinical samples is often complex and time‐consuming. Hence, several manual and automated rapid commercial systems for identifying these organisms have been developed, some of which may have significant sensitivity issues. To overcome these limitations, newer molecular typing techniques have been developed that allow accurate and rapid identification of Candida species. This study reviewed the current state of identification methods for yeasts, particularly Candida species. 相似文献
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Ananda da Silva Antonio Davi Santos Oliveira Gustavo Ramalho Cardoso dos Santos Henrique Marcelo Gualberto Pereira Larissa Silveira Moreira Wiedemann Valdir Florêncio da Veiga-Junior 《RSC advances》2021,11(40):25096
Untargeted metabolomics is a powerful tool in chemical fingerprinting. It can be applied in phytochemistry to aid species identification, systematic studies and quality control of bioproducts. This approach aims to produce as much chemical information as possible, without focusing on any specific chemical class, thus, requiring extensive chemometric effort. This study aimed to evaluate the feasibly of an untargeted metabolomics method in phytochemistry by a study case of the Copaifera genus (Fabaceae). This genus contains significant medicinal species used worldwidely. Copaifera exploitation issues include a lack of chemical data, ambiguous species identification methods and absence of quality control for its bioproducts. Different organs of five Copaifera species were analysed by UHPLC-HRMS/MS, GNPS platform and chemometric tools. Untargeted metabolomics enabled the identification of 19 chemical markers and 29 metabolites, distinguishing each sample by species, plant organs, and biome type. Chemical markers were classified as flavonoids, terpenoids and condensed tannins. The applied method provided reliable information about species chemodiversity using fast workflow with little sampling size. The untargeted approach by UHPLC-HRMS/MS proved to be a promising tool for species identification, pharmacological prospecting and in the future for the quality control of extracts used in the manufacture of bioproducts.UHPLC-HRMS/MS untargeted metabolomics enabled distinction of Copaifera extracts by species, vegetative parts, and biome of origin based on 19 chemical markers. 相似文献
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Suelem Pereira da Cruz Sabrina Cruz Silvia Pereira Carlos Saboya Juliana Castelar Lack Veiga Andra Ramalho 《Nutrients》2022,14(3)
Evaluating the influence of vitamin D concentrations together with preoperative metabolic phenotypes on remission of chronic noncommunicable diseases (CNCDs) after 6 months of Roux-en-Y gastric bypass (RYGB). Cross-sectional analytical study comprising 30 adult individuals who were assessed preoperatively (T0) and 6 months (T1) after undergoing RYGB. Participants were distributed preoperatively into metabolically healthy obese (MHO) and metabolically unhealthy obese (MUHO) individuals according to HOMA-IR classification and to the adequacy and inadequacy of vitamin D concentrations in the form of 25(OH)D. All participants were assessed for anthropometric characteristics, biochemical variables, and presence of CNCDs. The statistical program used was the SPSS version 21. In face of vitamin D adequacy and regardless of the metabolic phenotype classification in the preoperative period, the means found for HOMA-IR allowed us to define them as metabolically healthy 6 months after RYGB. Only those with vitamin D inadequacy with the MUHO phenotype showed better results regarding the reduction of glucose that accompanied the shift in serum 25(OH)D concentrations from deficient to insufficient. It is possible that preoperative vitamin D adequacy, even in the presence of an unhealthy phenotype, may contribute to the reduction of dyslipidemia and improvement in cholesterol. It is suggested that preoperative vitamin D adequacy in both phenotypes may have a protective effect on metabolic health. 相似文献
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Serum markers of hepatitis B virus replication, liver histology and intrahepatic expression of hepatitis B core antigen 总被引:3,自引:0,他引:3
F Ramalho M R Brunetto G Rocca G G Piccari A Batista E Chiaberge C Lavarini R P Dal Monte M Carneiro de Moura F Bonino 《Journal of hepatology》1988,7(1):14-20
The presence and distribution of hepatitis B core antigen (HBcAg) was studied in the liver of 227 chronic carriers of hepatitis B surface antigen (HBsAg) to investigate its relationship with serum HBV-DNA, the status of hepatitis B 'e' antigen/antibody (HBeAg/anti-HBe) and the underlying liver disease. HBcAg was detected in 144 of the 227 (63%) liver specimens and HBV-DNA in 132 (58%) of the corresponding sera. Serum HBV-DNA showed a constant link with intrahepatic HBcAg. Out of 96 HBeAg-positive patients, 91 (95%) had HBcAg in the liver and 85 (89%) had HBV-DNA in serum. Overall there was a significant link between HBeAg and HBV-DNA in serum, but there was no correlation in 58 out of 227 (26%) cases. In HBeAg/HBV-DNA-positive carriers, HBcAg expression was predominantly nuclear. It was nuclear and cytoplasmic in patients with the highest levels of viremia. Eleven out of 13 (85%) HBV-DNA-positive patients who had only cytoplasmic HBcAg were HBcAg-negative and had low levels of HBV-DNA. Nine of 13 (69%) patients with exclusively cytoplasmic HBcAg had severe chronic liver disease. Neither the presence of HBV-DNA and HBeAg in serum nor the nuclear localization of HBcAg were associated with the severity of liver damage. In the group of HBV-DNA-positive patients (132), the presence of liver disease was significantly connected with the absence of HBeAg in serum (P less than 0.05; C.L. 3-35).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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This study aimed to assess factors associated with overweight and obesity in adults from Rio Branco, Acre, in the western Brazilian Amazon. This is a cross-sectional, population-based study conducted in Rio Branco, which used data on individuals aged 18 years or older collected by the 2019 National Health Survey. Software R version 4.0.5 was used to estimate the prevalence of overweight and obesity, prevalence ratios, and 95% confidence intervals. Multiple analysis was performed by Poisson’s regression with robust variance and hierarchical selection of variables. This study included 1217 adults. The prevalence of overweight was 58.2% (95%CI: 54.7–61.6) and of obesity, 20.1% (95%CI: 17.2–23.4). The factors associated with overweight were arterial hypertension (AdjPR: 1.45; 95%CI: 1.31–1.61), physical inactivity (AdjPR: 1.19; 95%CI: 1.04–1.36), age group (25–39 years, AdjPR: 1.49; 95%CI: 1.10–2.00; 40–59 years, AdjPR: 1.69; 95%CI: 1.28–2.23; 60 years or older, AdjPR: 1.37; 95%CI: 1.01–1.87); and smoking (AdjPR: 0.62; 95%CI: 0.41–0.93). The factors associated with obesity were arterial hypertension (AdjPR: 1.80; 95%CI: 1.41–2.30) and diabetes mellitus (AdjPR: 1.52; 95%CI: 1.08–2.13). Smoking and female sex remained in the hierarchical model for obesity, even without statistical significance. Despite intervention guidelines for these chronic diseases, there is a need for the public recognition of overweight and obesity and their possible associated factors in the Amazon and other regions with similar socioeconomic and demographic characteristics. 相似文献
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Compri MB Saad ST Ramalho AS 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》2000,16(2):335-342
This paper reports on a study of the G-6-PD deficiency in Bragan?a Paulista, S?o Paulo State, Brazil. A total of 4,621 male blood donors were investigated over a 36-month period. Of these, 80 had the G-6-PD deficiency. Molecular analysis was performed on 70 unrelated G-6-PD deficients through DNA amplification followed by digestion with restriction enzymes and single strand conformation polymorphism analysis (SSCP). In 98.6%, the G-6-PD A- (202 G<--A) mutation was observed through digestion of exon 4 with Nla III. The presence of an uncommon mutation in exon 9 was also observed through SSCP. No case of the Mediterranean variant was observed. These results indicate that the A- (202G<--A) variant, almost exclusive, was introduced into the community not only by individuals of African origin, but also by European immigrants, mainly Italian, Spanish, and Portuguese. The Italian contribution in terms of the G-6-PD Mediterranean variant was smaller than its contribution to beta thalassemia, probably due to the Northern Italian origin of these immigrants. 相似文献