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411.
In the search for a sound model of consciousness, we aim at introducing new concepts: closure, compositionality, biobranes and autobranes. This is important to overcome reductionism and to bring life back into the neuroscience of consciousness. Using these definitions, we conjecture that consciousness co-arises with the non-trivial composition of biological closure in the form of biobranes and autobranes: conscious processes generate closed activity at various levels and are, in turn, themselves, supported by biobranes and autobranes. This approach leads to a non-reductionist biological and simultaneously phenomenological theory of conscious experience, giving new perspectives for a science of consciousness. Future works will implement experimental definitions and computational simulations to characterize these dynamical biobranes interacting. 相似文献
412.
Jaimes MB Cáceres DC de la Hoz F Gutiérrez C Herrera D Pinilla J Porras A Rodríguez F Velandia M 《Biomédica : revista del Instituto Nacional de Salud》2003,23(3):283-292
Severity of acute respiratory infection is higher in developing countries, especially among the socioeconomically underprivileged. Viral pneumonias are more common, especially among children. A prospective hospital-based case control study was undertaken in Bogota between November 2000 and August 2001, aimed to identify factors related to severe low acute respiratory infection (SLARI). Cases were limited to children aged between 2 months and 5 years who filled WHO criteria for SLARI. Controls were children at the same hospital with ARI in a similar age range, but without symptoms of chest drawing. A total of 638 children (277 cases and 361 controls) were included. The most important risk factors included the following: living in borrowed houses (odds ratio (OR) = 2.7; 95% Confidence Interval (CI): 1.06-7.07), sharing the bed (OR = 1.88, CI: 1.0-3.7), living with more than 9 people (OR = 1.82, CI: 1.0-3.51), and living with smokers (OR = 1.4, CI: 1.0-2.05). Of the 114 samples collected (from children at third day after beginning of symptoms), 98 had viruses, sincitial respiratory virus was the most frequently identified virus (41.8%), followed by influenza A virus (3.1%) and influenza B virus (1%). All positive isolates for influenza A and B were sent to the United States Center for Disease Control (CDC) in Atlanta, where they were classified as influenza A/PANAMA/2007/99-like and influenza B/SICHUAN/379/99-like, respectively. 相似文献
413.
414.
Boll MC Alcaraz-Zubeldia M Montes S Murillo-Bonilla L Rios C 《Neurochemical research》2003,28(5):699-703
To determine whether or not the occurrence of sporadic amyotrophic lateral sclerosis (sALS) is associated with both excess nitric oxide (NO) metabolites and decreased protective superoxide dismutase (SOD) activity in the cerebrospinal fluid (CSF), we measured nitrate concentration and SOD activity in the CSF of sALS patients and in age- and gender-matched controls. We found stable NO metabolite levels to be significantly higher and SOD activity lower in the CSF of sALS patients. In addition, SOD showed a negative correlation with motor neuron axonal damage expressed as the amplitude of motor action potentials in upper limbs. Our results provide new evidence in vivo suggesting that NO products and SOD activity play a role in oxidant/antioxidant imbalance in sporadic ALS. 相似文献
415.
Surface-relief gratings and photoinduced birefringence in layer-by-layer films of chitosan and an azopolymer 总被引:1,自引:0,他引:1
Camilo CS dos Santos Júnior DS Rodrigues Júnior JJ Vega ML Campana Filho SP Oliveira Júnior ON Mendonça CR 《Biomacromolecules》2003,4(6):1583-1588
Layer-by-layer (LBL) films of chitosan alternated with an azopolymer, PS119, have been used for optical storage and fabrication of surface-relief gratings. The optical properties stem from the trans-cis-trans isomerization cycles undergone by the azochromophore, with a kinetics for writing the birefringence pattern that is much slower than in the spin-coated or cast films of azopolymers. The long writing times, of the order of 100 s, are due to the electrostatic interactions between adjacent chitosan and PS119 layers. Such interactions are also responsible for other features in the LBL films, namely the increase in the amount of adsorbed material when the pH of the preparation solution is decreased and the large residual birefringence after the writing laser is switched off. Gratings could be inscribed with s-polarized but not with p-polarized light, indicating a mass transport process associated with photodegradation. 相似文献
416.
Mattosinho de Castro Ferraz Mda G Dall' Agnol M di Loreto C Pirani WM Utagawa ML Pereira SM Sakai YI Feres CL Shih LW Yamamoto LS Rodrigues RO Shirata NK Longatta Filho A 《Acta cytologica》2005,49(6):639-643
OBJECTIVE: To verij5 the efficacy of the quality control (QC) program in a cytologic laboratwy with a rapid rescreening (RR) protocol. STUDY DESIGN: RR, according to the Turret RR method, of all samples initially screened as negative at the Laboratory of Cytology, Adolfo Lutz Institute, was performed. The slides were reviewed for 60 seconds. Suspect smears were fully checked by 2 reviewers to determine the final diagnoses. A total of 2954 sequential cytologic results were considered in this study. Of the 2954, 2568 (86.9%) were considered initially negative according to our internal QC, and these cases underwent RR. Also, 10% were randomly selected from these negative cases for full reviewing. The internal QC in our laboratory includes review of cases selected according to clinical and cytomorphologic criteria. RESULTS: Among the 2954 total cases, QC detected 386 (13%) atypias with final diagnoses reported according to The Bethesda System 2001 as follows: 82 (2.18%) low grade squamous intraepithelial lesions (LSILs), 35 (1.18%) high grade squamous intraepithelial lesions (HSILs), 2 (0.06%) squamous cell carcinomas, 105 (3.5%) atypical cells of undetermined significance (ASC-US), 4 (0.12%) atypical endocervical cells (AECs) and 158 (5.3%) unsatisfactory samples. RR of 2568 smears initially considered negative selected 194 (7.5%) slides. Of the 194, 146 (75.3%) were negative, 28 (14.4%) ASC-US, 5 (2.6%) AEC, 1 (0.5%) LSIL and 14 (7.2%) unsatisfactory. Full review of a 10% random fraction of the 2568 cases interpreted as negative did not detect lesions but did detect 5 (1.95%) unsatisfactory samples. CONCLUSION: Internal QC used in our laboratory based on clinical and cytomorphologic criteria to select cases for review proved to be an efficient method of detecting HSIL and cervical cancer. The consensus basis of this program strongly limits the false positive and false negative rates and also provides subjects with continuing education. One hundred percent RR is more efficient than 10% full reviewing in detecting cervical abnormalities. 相似文献
417.
Anderson JV Delseny M Fregene MA Jorge V Mba C Lopez C Restrepo S Soto M Piegu B Verdier V Cooke R Tohme J Horvath DP 《Plant molecular biology》2004,56(4):527-539
Cassava (Manihot esculenta) is a major food staple for nearly 600 million people in Africa, Asia, and Latin America. Major losses in yield result from biotic and abiotic stresses that include diseases such as Cassava Mosaic Disease (CMD) and Cassava Bacterial Blight (CBB), drought, and acid soils. Additional losses also occur from deterioration during the post-harvest storage of roots. To help cassava breeders overcome these obstacles, the scientific community has turned to modern genomics approaches to identify key genetic characteristics associated with resistance to these yield-limiting factors. One approach for developing a genomics program requires the development of ESTs (expressed sequence tags). To date, nearly 23000 ESTs have been developed from various cassava tissues, and genotypes. Preliminary analysis indicates existing EST resources contain at least 6000–7000 unigenes. Data presented in this report indicate that the cassava ESTs will be a valuable resource for the study of genetic diversity, stress resistance, and growth and development, not only in cassava, but also other members of the Euphorbiaceae family. 相似文献
418.
Cristian Camilo Martínez‐González William González‐Daza José Iván Mojica 《Zeitschrift fur angewandte Ichthyologie》2018,34(5):1216-1219
This study estimated the a and b parameters of the length–weight relationships of 15 fishes from the Mira and Caunapí rivers, San Andrés de Tumaco, Nariño, Colombia. The specimens were captured during four samplings periods between 2015 and 2016 using a different a combination of fishing gillnets and electrofishing. The a values ranged from 0.0002 to 0.04 and b values ranged from 2.86 to 3.6. The data presented here are tentative estimates because the fish have been weighted and measured after fixation in formalin and ethanol, however, these data are references for weight‐length relationship for 15 species, the maximum weight for the same 15, and new maximum lengths for 3 species. 相似文献
419.
Aluminium foil as an alternative substrate for the spectroscopic interrogation of endometrial cancer 下载免费PDF全文
Maria Paraskevaidi Camilo L.M. Morais Olivia Raglan Kássio M.G. Lima Evangelos Paraskevaidis Pierre L. Martin‐Hirsch Maria Kyrgiou Francis L. Martin 《Journal of biophotonics》2018,11(7)
Biospectroscopy has the potential to investigate and characterize biological samples and could, therefore, be utilized to diagnose various diseases in a clinical environment. An important consideration in spectrochemical studies is the cost‐effectiveness of the substrate used to support the sample, as high expense would limit their translation into clinic. In this paper, the performance of low‐cost aluminium (Al) foil substrates was compared with the commonly used low‐emissivity (low‐E) slides. Attenuated total reflection‐Fourier transform infrared spectroscopy was used to analyse blood plasma and serum samples from women with endometrial cancer and healthy controls. The 2 populations were differentiated using principal component analysis with support vector machines with 100% sensitivity in plasma samples (endometrial cancer = 70; healthy controls = 15) using both Al foil and low‐E slides as substrates. The same sensitivity results (100%) were achieved for serum samples (endometrial cancer = 60; healthy controls = 15). Specificity was found higher using Al foil (90%) in comparison to low‐E slides (85%) and lower using Al foil (70%) in comparison to low‐E slides in serum samples. The establishment of Al foil as low‐cost and highly performing substrate would pave the way for large‐scale, multicentre studies and potentially for routine clinical use.
420.
Alexander Turra Aldo Cróquer Alvar Carranza Andrés Mansilla Arsenio J. Areces Camilo Werlinger Carlos Martínez‐Bayón Cristina Aparecida Gomes Nassar Estela Plastino Evangelina Schwindt Fabrizio Scarabino Fungyi Chow Felix Lopes Figueroa Flávio Berchez Jason M. Hall‐Spencer Luis A. Soto Marcos Silveira Buckeridge Margareth S. Copertino Maria Tereza Menezes de Széchy Natalia Pirani Ghilardi‐Lopes Paulo Horta Ricardo Coutinho Simonetta Fraschetti Zelinda Margarida de Andrade Nery Leão 《Global Change Biology》2013,19(7):1965-1969
As the effects of the Global Climate Changes on the costal regions of Central and South Americas advance, there is proportionally little research being made to understand such impacts. This commentary puts forward a series of propositions of strategies to improve performance of Central and South American science and policy making in order to cope with the future impacts of the Global Climate Changes in their coastal habitats. 相似文献