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1.
Developing thymocytes are selected for recognition of molecules encoded by the major histocompatibility complex, purged of self-reactive cells and committed to either the CD4 or CD8 lineage. The 1% of thymocytes that complete these tasks emigrate and join the population of peripheral lymphocytes. Whether T cell maturation is complete at the time of thymic exit has been a subject of debate. Using mice transgenic for green fluorescent protein driven by the recombination activating gene 2 promoter to identify recent thymic emigrants, we now show that T cell differentiation continues post-thymically, with progressive maturation of both surface phenotype and immune function. In addition, the relative contribution of CD4 and CD8 recent thymic emigrants was modulated as they entered the peripheral T cell pool. Thus, T cell maturation and subset contribution are both finalized in the lymphoid periphery.  相似文献   
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To overcome the challenge of obtaining accurate data on community food retail, we developed an innovative tool to automatically capture food retail data from Google Earth (GE). The proposed method is relevant to non-commercial use or scholarly purposes. We aimed to test the validity of web sources data for the assessment of community food retail environment by comparison to ground-truth observations (gold standard). A secondary aim was to test whether validity differs by type of food outlet and socioeconomic status (SES). The study area included a sample of 300 census tracts stratified by SES in two of the largest cities in Brazil, Rio de Janeiro and Belo Horizonte. The GE web service was used to develop a tool for automatic acquisition of food retail data through the generation of a regular grid of points. To test its validity, this data was compared with the ground-truth data. Compared to the 856 outlets identified in 285 census tracts by the ground-truth method, the GE interface identified 731 outlets. In both cities, the GE interface scored moderate to excellent compared to the ground-truth data across all of the validity measures: sensitivity, specificity, positive predictive value, negative predictive value and accuracy (ranging from 66.3 to 100%). The validity did not differ by SES strata. Supermarkets, convenience stores and restaurants yielded better results than other store types. To our knowledge, this research is the first to investigate using GE as a tool to capture community food retail data. Our results suggest that the GE interface could be used to measure the community food environment. Validity was satisfactory for different SES areas and types of outlets.  相似文献   
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Objective: To assess the feasibility and safety of a physiotherapy protocol applied to pregnant women with preeclampsia. Methods: Randomized, controlled, single-blind feasibility study, with 24 hospitalized pregnant women with preeclampsia. The intervention group received one session of the physiotherapy. The control group remained under the routine care of the hospital. The primary outcomes were Doppler velocimetry, cardiotocography, and maternal–fetal hemodynamics. Secondary outcomes were pain and anxiety assessed before and after the interventions. A mixed effects linear regression model was used, and the data were compared with the level of significance at 5%. Results: The baseline characteristics of the participants were homogeneous between groups. Resistance index of the Middle Cerebral Artery (MAC) and Umbilical Artery (UA) and cardiotocography did not change significantly. The systolic blood pressure (SBP) increased 4.90 mmHg in the control group and 0.22 mmHg in the intervention group. The diastolic blood pressure (DBP) increased 1.34 mmHg in the control group and decreased 0.40 mmHg in the intervention group. The middle bood pressure (MBP) increased 4.66 mmHg in the control group while there was a decrease of 0.09 mmHg in the intervention group, without statistical difference. Heart rate (HR) decreased 0.94 bpm in the control group; whereas, in the intervention group, there was an increase of 6.30 bpm. The pain reduced clinically 2 points after the intervention. The anxiety reduced clinically in both the groups (?1.26 in the intervention group and ?2.17 in the control group). Conclusion: The protocol applied in the intervention group is feasible and safe for both mother and fetus. Both groups showed clinical reduction in the levels of anxiety; whereas, pain was clinically reduced in the intervention group.  相似文献   
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ObjectivesTo determine the prevalence of pneumococcal serotypes and antimicrobial susceptibility in patients with meningitis, and to evaluate the implications for vaccine coverage.MethodsPneumococcal strains obtained from normally sterile fluids from patients admitted with meningitis were isolated at the Hospital de Clínicas of the Universidade Federal de Uberlândia, Minas Gerais State, and sent to the Instituto Adolfo Lutz, city of São Paulo, São Paulo State, for further identification, serotyping, and antimicrobial susceptibility determination.ResultsFrom April 1999 to April 2009, 338 pneumococcal strains were isolated, and 72 obtained from patients with meningitis, were analyzed. Patients’ ages varied from one month to 82.2 years (mean of 18.4 ± 22.9 years; median of 5.2 years) and 46 (63.9%) patients were male. Strains were isolated from cerebrospinal fluid [66 occasions (91.7%)] and blood [6 occasions (8.3%)]. The most commonly identified serotypes were 14, 19F, 3, 7F, 6A, 6B, 10A, 18C, 23F, 5, and 34. Of the 20 [27.8%] oxacillin-resistant strains, 17 [23.6%] were resistant to penicillin and nine [12.5%] to ceftriaxone, both resistance patterns being more common in children aged two years or less and during the 2005–2009 period.ConclusionsResistance to penicillin and ceftriaxone was detected in 23.6% and 12.5% of the strains, respectively, and predominated in children aged two years or less and during the 2005–2009 period. There were 24 different serotypes of pneumococcus and 79.8% of the serotypes were represented in the 7-valent conjugated vaccine [PVC7].  相似文献   
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ObjectiveThe purpose of this study was to quantify the impact of a single lumbar spinal manipulation (SM) intervention on the leg movement performance of degenerative lumbar spinal stenosis (LSS) patients in a small-scale registered randomized clinical trial.MethodsParticipants with LSS (n = 14) were tested at baseline for pain, lumbar range of motion, and behavioral or kinematic motor performance (using an established Fitts’ Law foot-pointing task), then underwent covariate adaptive randomization to receive SM or no intervention. Postintervention all dependent measures were repeated. Experimenters were blinded to patient group allocation. University ethics board approval was attained.ResultsFor the primary outcome movement time, there was no significant difference between groups. As predicted by Fitts’ Law, all participants had longer movement times as task difficulty increased. Secondary kinematic outcomes yielded no significant between-group differences. Consistent with Fitts’ Law, kinematic measures changed significantly with task difficulty. Pairwise comparisons revealed the kinematic variables were more adversely affected by greater movement amplitudes than target size changes. No exploratory differences in pain or lumbar range of motion were observed.ConclusionChanges in motor performance were not observed in this chronic pain population after a single SM intervention compared with a control group. Given the sample size, the study may have been underpowered to detect meaningful differences. Fitts’ Law was observed for the lower extremity–pointing task for an LSS population and may provide an objective measure of motor performance.  相似文献   
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American cutaneous leishmaniasis is in full geographic expansion in Brazil and it is considered among the infectious and parasitic diseases of utmost importance worldwide, not only by its frequency, but mainly by therapeutic difficulties, deformities and sequelae that may result. In the state of Rio de Janeiro, the first autochthonous case of American cutaneous leishmaniasis was registered by Rabello in 1913. The authors report two cases of the disease in the region around the Cemetery São Francisco Xavier, in the Caju neighborhood, Rio de Janeiro city, and emphasize the need for actions that aim to early diagnosis and treatment of American cutaneous leishmaniasis cases.  相似文献   
9.
Objective: To evaluate the perinatal results from epileptic women using antiepileptic drugs during prenatal care.

Methods: This was a retrospective longitudinal study assessing the perinatal results of women exposed to antiepileptic drugs during pregnancy, and we compared these results with those of pregnant women who were not exposed. The development of pregnancy, gestational age at delivery, Apgar scores, biometric data, morbidity, stillbirths and neonatal mortality were analyzed. The chi-square test and Fisher’s exact test were used for the categorical variables, while Student’s t-test was used for independent numerical variables.

Results: Over a 10-year period, 12?790 singleton gestations were analyzed, among which 104 (0.8%) consisted of epileptic pregnant women. From this total, 82 evolved to childbirth and their neonatal data were compared with those of 316 newborns from non-epileptic women. The most-used antiepileptic drug was phenobarbital in 70% of the cases. There was greater neonatal mortality (p?=?0.006), occurrence of neonatal hemorrhagic disorders (p?=?0.005), and occurrence of minor congenital anomalies (p?=?0.03) among the children of women exposed to antiepileptic drugs.

Conclusion: The antenatal exposure to antiepileptic drugs is associated mainly with occurrences of hemorrhagic complications during the neonatal period; furthermore, great prevalence of newborns presenting minor congenital anomalies and elevated risk of neonatal mortality.  相似文献   

10.
Objective: To describe a new technique for assessing fetal growth using three-dimensional ultrasonography (3DUS) using the extended imaging virtual organ computer-aided analysis (XI VOCAL) software and its respective reference curves.

Methods: We conducted a cross-sectional study on 303 normal singleton pregnancies between their 20th and 34th weeks. To assess fetal heart growth, we used the XI VOCAL software with 10 planes in which the reference lines (beginning and end) were placed at the cardiac apex, the output level of the vessels and the base above the diaphragm, respectively. To assess the correlation between distance and interval, polynomial regressions were performed with adjustments using the coefficient of determination (R2). To assess the inter-observer reproducibility, we used the intraclass correlation coefficient (ICC).

Results: The mean distance between the apex and the base of the fetal heart ranged from 14.41?±?1.24?mm to 26.24?±?2.62?mm between the 20th and 34th weeks, respectively. The mean interval between the apex and the base of the fetal heart ranged from 1.56?±?0.13?mm and 2.94?±?0.30?mm between the 20th and 34th weeks, respectively. We observed good correlation of distance and interval with the gestational age, with R2?=?0.73 and 0.74, respectively. We observed a good inter-observer to the interval and distance with ICC?=?0.983 and 0.996, respectively.

Conclusion: We described a new technique for assessing fetal heart growth using 3DUS and determined reference curves for the distance and interval between the 20th and 34th weeks of pregnancy.  相似文献   
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