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排序方式: 共有1628条查询结果,搜索用时 15 毫秒
1.
Fernando Regla Vargas Jos Carlos Cabral de Almeida Juan Clinton Llerena Dimas Fagundes Reis 《American journal of medical genetics. Part A》1992,44(6):716-719
We report on a boy with severe radial hypoplasia, absent thumbs and patellae, short stature, persistent diarrhea, slender nose and normal intelligence as another example of the RAPADILINO syndrome. © 1992 Wiley-Liss, Inc. 相似文献
2.
3.
M J Evans L J Cabral R J Stephens G Freeman 《Experimental and molecular pathology》1975,22(1):142-150
This research was undertaken to study the fate of Type 2 cells after they have divided. To accomplish this, male rats were exposed to NO2 to increase the number of dividing Type 2 cells. Dividing cells were labeled with 3H-TdR and studied with autoradiographic techniques in the electron microscope for up to 14 days after labeling. The results show that initially most of the 3H-TdR labeled cells were Type 2. However, by 2 days there was a decrease in frequency of labeled Type 2 cells and a large increase in labeled Type 1 cells. The new frequencies of labeled alveolar epithelial cells were stable from 2 through 14 days. This evidence supports the interpretation that Type 2 cells may transform into Type 1 cells. In addition, it was shown that under the conditions of this experiment: (1) the time for transformation was about 2 days, and (2) during this process an intermediate cell type was present. 相似文献
4.
Well-characterised human osteoblastic bone marrow cell cultures are a useful in vitro tool to analyse bone tissue/biomaterials interactions. In this work, human bone marrow was cultured in experimental conditions described to favour osteoblastic differentiation and, serially passaged cells were cultured in two widely used culture media, minimum essential medium Eagle, alpha modification (alpha-MEM) and Dulbecco's modified Eagle's medium (DMEM). Cultures were grown for 35 d and compared concerning morphologic appearance on scanning electron microscopy (SEM), cell viability/proliferation, total protein content, activity of alkaline phosphatase (ALP) and ability to form calcium phosphate deposits. Results showed that cell proliferation was similar in cultures grown in the two media but ALP activity and ability to form mineralised deposits were lower in DMEM cultures. In both experimental situations, osteoblastic parameters were strongly reduced on cell passage, particularly from the first to the second subculture. In the experimental conditions used (presence of ascorbic acid, sodium beta-glycerophosphate and dexamethasone in the primary and secondary cultures), osteoblastic differentiation was observed in the first and second subcultures grown in alpha-MEM and in the first subculture grown in DMEM. These results underline the importance of the definition of the experimental conditions in studies involving bone cell cultures. 相似文献
5.
Gontijo AM Marcondes JP Elias FN de Oliveira ML de Lima RO Salvadori DM de Camargo JL 《Environmental and molecular mutagenesis》2002,40(3):190-199
In order to determine if patients with a history of previous urothelial cell carcinoma (UCC) but with current normal urinary cytology have DNA damage in urothelial cells, the single-cell gel electrophoresis (comet) assay was conducted with cells obtained by urinary bladder washings from 44 patients (28 with a history of previous UCC). Increased DNA damage was observed in cytologically "normal" urothelial cells of patients with a history of UCC when compared with referents with no similar history and after correcting the data for smoking status and age (P < 0.018). Increased DNA damage also correlated with the highest tumor grade, irrespective of time or course of the disease after clinical intervention (Kendall tau correlation, 0.37, P = 0.016). Moreover, aneuploidy, as assessed by DNA content ratio (DCR; 75th/25th percentile of total DNA fluorescence of 50 comets/patient) was unaltered by smoking status, but increased with UCC grade: 1.39 +/- 0.12 (median +/- 95% confidence interval; referents); 1.43 +/- 0.11 (Grade I UCC; P = 0.264, against referents); 1.49 +/- 0.16 (Grade II UCC; P = 0.057); 1.57 +/- 0.16 (Grade III UCC; P = 0.003). Micronucleated urothelial cells (MNC) were also scored on Giemsa-stained routine cytological smears and were found not to correlate with DNA damage or DCR. MNC frequencies were higher for patients with a history of UCC and/or smoking than referents with neither history, but there was no statistical difference between groups. Taken together, these results suggest that the normal-appearing urothelium of patients resected for UCC still harbor genetically unstable cells. 相似文献
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7.
Goraib JA Cabral JA Nogueira AR Barbosa CN Bordallo F Carvalho M Lopes JM 《Jornal de pediatria》1995,71(1):41-44
Epignathus is a congenital teratoide tumor in the oral cavity. It is extremely rare and usually lethal. The authors present a case treated successfully. Important aspects of the diagnosis, clinical management and surgical procedures are discussed. Extensive review of the literature is presented. 相似文献
8.
Oliveira EA Diniz JS Cabral AC Leite HV Colosimo EA Oliveira RB Vilasboas AS 《Pediatric nephrology (Berlin, Germany)》1999,13(9):859-864
With the increasing use of obstetric echography fetal hydronephrosis has been reported more frequently. The purpose of this
study was to identify prognostic factors associated with adverse outcome, such as renal failure and death, in fetal hydronephrosis.
One hundred and forty-eight children with fetal hydronephrosis were admitted, submitted to a systematic protocol, and prospectively
followed. Prognostic factors associated with fetal echography and clinical and laboratory findings on admission were studied.
The median follow-up was 39 months. The analysis was conducted in two steps. In a univariate analysis, variables associated
with adverse outcome were identified by the Kaplan-Meier method. The variables that were significantly associated with adverse
outcome were then included in a multivariate analysis. This analysis, using the multivariate Cox’s model, was performed to
identify variables that were independently associated with a worse prognosis. Only variables that remained independently associated
with adverse outcome were included in the final model. After final adjustment by Cox’s multivariate model, three variables
were identified as independent predictors of adverse outcome: oligohydramnios, prematurity, and glomerular filtration rate
lower than 20 ml/min. Thus, in the presence of oligohydramnios, prematurity, and abnormal renal function, the medical team
must plan appropriate follow-up for infants at health centers prepared to investigate and treat uropathies in newborns.
Received: 24 August 1998 / Revised: 7 December 1998 / Accepted: 11 December 1998 相似文献
9.
Pedro Cabral 《European journal of paediatric neurology》2006,10(2):66-77
Attention deficit disorder (AAD) and attention deficit/hyperactivity disorder (ADHD) are very frequent and protean developmental disorders without a definite biologic marker. This review proposes a framework to understand the enlarged spectrum of its manifestations based on current knowledge of the mechanisms underlying arousal and attention variations during sleep/wake cycle. The neuro-modulation's pivotal role in this process as well as in the fine tuning of synaptic architecture during development must be taken into account when trying to understand the marked fuzziness of the symptoms and the very high prevalence of reported co-morbidities. The series of related interactions includes a cyclic deactivation of the dorso-lateral portion of the prefrontal cortex (DLPFC) during sleep, suspending executive functions, co-occurring with rhythmic periods of decreased noradrenergic tonus. A protracted unbalance in modulation, with catecholaminergic relative deficiency, could explain less-than-optimum waking DLPFC activation and the most important manifestations of ADD. Beside the well documented dopaminergic effects of stimulant medication used in ADD and ADHD, a more important role must be assigned to noradrenaline (NA). At this light hyperactivity and impulsivity are less important dimensions. Rather, an attention deficit spectrum disorder should probably be regarded as a complication of a core defect in prefrontal cortex dependent inhibitory control, underlying inattention. 相似文献
10.
Bernardo L. Teixeira Joo Cabral Andr Marques-Pinto Fernando Vila Joaquim Lindoro Avelino Fraga 《Canadian Urological Association journal》2022,16(5):E267
IntroductionWe aimed to compare the rate of postoperative infection and drug-resistant organism (DRO) before and during the COVID-19 pandemic in urology departments.MethodsA retrospective cohort study was carried out. Data from all elective surgical procedures carried out in two urology departments between April and June 2018 and the homologous period in 2020 were collected. Main outcomes were the number of postoperative infections during the pandemic and the number of DROs. Sample size was calculated based on a 50% relative reduction of infections during the pandemic. Variables were compared by Chi-squared test, and multivariable logistic regression was used to estimate predictors.ResultsA total of 698 patients undergoing elective surgery were included. The postoperative infection rate during the pre-pandemic period was of 14.1% compared to 12.1% during the pandemic (p=0.494). DROs were lower during the pandemic (92.3% vs. 52.4%, p=0.002). The pandemic period was the main predictor for reduced multidrug-resistant isolates, with an odds ratio of 0.10 (p=0.010, 95% confidence interval 0.016–0.57).ConclusionsPostoperative infection rates were not significantly reduced during the COVID-19 pandemic, despite the adoption of enhanced infection preventive measures. There was, however, a decrease in the rate of DROs during this period, suggesting a secondary benefit to enhanced infection prevention practices adopted during the COVID-19 era. 相似文献