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排序方式: 共有9085条查询结果,搜索用时 18 毫秒
51.
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Andra Araujo Brando Weimar Kunz Sebba Barroso Audes Feitosa Eduardo Costa Duarte Barbosa Roberto Dischinger Miranda Priscila Valverde de Oliveira Vitorino Roberto Pozzan Lucio Paulo Ribeiro Abraham Epelman Giovanni Alves Saraiva Fabio Serra Silveira Antnio Almeida Braga Marco Mota Gomes 《Arquivos brasileiros de cardiologia》2022,119(2):353
53.
Karen D. Wright MD MS Mihaela M. Onciu MD Elaine Coustan‐Smith MS Dario Campana MD PhD Susana C. Raimondi PhD Hiroto Inaba MD PhD Raul Ribeiro MD Ching‐Hon Pui MD John T. Sandlund MD 《Pediatric blood & cancer》2013,60(7):E38-E41
Dendritic cell leukemia (DCL) or hematodermic tumor is an uncommon subtype of acute leukemia. In contrast to adult cases, children tend to have a less aggressive course. The diagnosis of DCL should be considered when its characteristic morphologic features are present and leukemic cells co‐express CD4 and CD56. Cases of DCL among pediatric patients have been reported to respond to therapeutic regimens for acute lymphoblastic leukemia, but details regarding the specifics of therapy are lacking. Pediatr Blood Cancer 2013; 60: E38–E41. © 2013 Wiley Periodicals, Inc. 相似文献
54.
Camilla Rodrigues de Almeida Ribeiro Katrini Guidolini Martinelli Vinícius da Motta de Mello Natlia Spitz Oscar Rafael Carmo Araújo Lia Laura Lewis-Ximenez Natalia Motta Araujo Vanessa Salete de Paula 《Viruses》2022,14(7)
Several hepatitis B virus (HBV)-related factors, including the viral load, genotype, and genomic mutations, have been linked to the development of liver diseases. Therefore, in this study we aimed to investigate the influence of HBV genetic variability during acute and chronic infection phases. A real-time nested PCR was used to detect HBV DNA in all samples (acute, n = 22; chronic, n = 49). All samples were sequenced for phylogenetic and mutation analyses. Genotype A, sub-genotype A1, was the most common genotype in the study population. A total of 190 mutations were found in the pre-S/S gene area and the acute profile revealed a greater number of nucleotide mutations (p < 0.05). However, both profiles contained nucleotide mutations linked to immune escape and an increased risk of hepatocellular carcinomas (acute, A7T; chronic, A7Q). Furthermore, 17 amino acid substitutions were identified in the viral polymerase region, including the drug resistance mutations lamivudine and entecavir (rtL180M), with statistically significant differences between the mutant and wild type strains. Owing to the natural occurrence of these mutations, it is important to screen for resistance mutations before beginning therapy. 相似文献
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Lisa Bastian Anumita Samanta Demetrius Ribeiro de Paula Frederik D. Weber Robby Schoenfeld Martin Dresler Lisa Genzel 《Human brain mapping》2022,43(13):3923
After experiences are encoded, post‐encoding reactivations during sleep have been proposed to mediate long‐term memory consolidation. Spindle–slow oscillation coupling during NREM sleep is a candidate mechanism through which a hippocampal‐cortical dialogue may strengthen a newly formed memory engram. Here, we investigated the role of fast spindle‐ and slow spindle–slow oscillation coupling in the consolidation of spatial memory in humans with a virtual watermaze task involving allocentric and egocentric learning strategies. Furthermore, we analyzed how resting‐state functional connectivity evolved across learning, consolidation, and retrieval of this task using a data‐driven approach. Our results show task‐related connectivity changes in the executive control network, the default mode network, and the hippocampal network at post‐task rest. The hippocampal network could further be divided into two subnetworks of which only one showed modulation by sleep. Decreased functional connectivity in this subnetwork was associated with higher spindle–slow oscillation coupling power, which was also related to better memory performance at test. Overall, this study contributes to a more holistic understanding of the functional resting‐state networks and the mechanisms during sleep associated to spatial memory consolidation. 相似文献
57.
de Faria DE Borges LV Peters VM Reis JE Ribeiro LC de Cássia da Silveira E Sá R Guerra Mde O 《Phytotherapy research : PTR》2008,22(2):185-189
The Gingko biloba extract is contraindicated during pregnancy and lactation due to the lack of information about its effects on these reproductive phases. Previous studies have shown that G. biloba extract contains components with estrogenic and antiestrogenic activities, thus nursing dams treated with the extract of this plant could show reduction in milk production, resulting in malnutrition and poor development of pups. This work analyzes the postnatal development of pups, whose mothers were treated with G. biloba extract during the lactation period. Nursing Wistar rats received 3.5 mg/kg/day of G. biloba aqueous extract, corresponding to the highest human dose. Clinical signs of maternal toxicity were evaluated. The growth rate, viability, survival during treatment and lactation indices of the pups were calculated. The physical, motor and sensorial development of the pups was also evaluated. No maternal signs of toxicity were observed. As there were no biological differences between control and G. biloba treated pups, it is possible to assume that, in this experimental design, the administration of G. biloba aqueous extract to nursing rats during the lactation period seems to be devoid of toxic effect to mothers and to the physical, motor and sensory development of the pups. 相似文献
58.
Martinho O Gonçalves A Moreira MA Ribeiro LF Queiroz GS Schmitt FC Reis RM Longatto-Filho A 《Gynecologic oncology》2008,111(2):350-355
ObjectivesUterine adenosquamous carcinoma (ASC) is an uncommon, yet, one of the most aggressive cervical cancer subtype. The successful treatment of some tumors, such as gastrointestinal stromal tumors (GISTs), by anti-KIT inhibitors fosters the study of this receptor tyrosine kinase in other malignancies. In the present study, we intended to molecularly characterize KIT in ASC.MethodsIn a series of 30 cases, we studied KIT (CD117), KIT phosphorylated / activated form, as well as KIT ligand, stem cell factor (SCF), by immunohistochemistry. We further screened for KIT hotspot mutations (exon 9, 11, 13 and 17) by PCR-SSCP and for KIT gene amplification by Quantitative real-time PCR in CD117 positive cases.ResultsWe observed CD117 expression in ~ 13% of cases, with ~ 7% co-expressing SCF, which resulted in KIT phosphorylation/activation. No KIT activating mutations or gene amplification were found, despite the presence of 4q aneuploidy in one case.ConclusionsThis is the first study assessing KIT activation and molecular alterations in a large series of rare ASC. Our findings showed the absence of KIT molecular alterations and suggested the presence of KIT activation in a small proportion of cases through KIT/SCF co-expression. 相似文献
59.
The levonorgestrel containing intrauterine system is an effective and safe form of long-term yet reversible birth control. Intrauterine contraception use in the United States fell dramatically after early studies reported an association between intrauterine contraception use and later tubal infertility. Subsequent evaluation suggests that these early studies were biased. Users often experience menstrual disturbances. Informing patients of these common side effects is important to improve compliance. In addition to its contraceptive effect, the levonorgestrel intrauterine system offers potential therapeutic benefits in other clinical contexts, including menorrhagia, symptomatic fibroids, endometriosis, and endometrial suppression. 相似文献
60.
dos Santos E dos Santos JE Ribeiro RP Rosa E Silva AC Moreira AC Silva de Sá MF 《Journal of pediatric and adolescent gynecology》2007,20(1):13-18
STUDY OBJECTIVE: To compare the cortisol levels and 24 hour salivary cortisol rhythm in patients with anorexia nervosa (AN) and normal controls. DESIGN: Prospective transversal controlled study. SETTING: Tertiary-referral University Hospital. PARTICIPANTS: Twenty-five patients aged 15 to 35 years, 13 of them with regular ovulatory cycles, and 12 with diagnosis of AN. INTERVENTIONS: Salivary and blood collection for cortisol 24-hour rhythm determination. MAIN OUTCOME: Salivary cortisol was determined at 9 am, 5 pm, and 11 pm. Seric follicle-stimulating hormone, luteinizing hormone (LH), prolactin, estradiol (E2), progesterone, dehydroepiandrosterone-S (DHEA-S), and cortisol were sampled together with the 9 am salivary sample. RESULTS: LH, E2, and DHEA-S levels were reduced in patients with AN. A correlation between salivary and serum cortisol levels was observed in the 9 am sample only in controls (r = 0.67, P = 0.01; AN: r = 0.48, P = 0.12). Cortisol rhythm was present in all control subjects, whereas it was absent in one third of AN patients. The area under the curve for the AN group with preserved rhythm was significantly higher than for the control group (Me = 6811 ng/dl/24h vs 3708 ng/dl/24 h; P = 0.034). CONCLUSION: Patients with AN have higher salivary cortisol levels when compared to normal women and some of them do not present circadian rhythm. 相似文献