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41.
Raine Adrian; Andrews Harry; Sheard Charlotte; Walder Cristine; Manders Duncan 《Canadian Metallurgical Quarterly》1989,98(1):35
Although several studies suggest that schizophrenics suffer from an impairment in the interhemispheric transfer (IHT) of information, methodological weaknesses in these studies preclude clear interpretation of their results. This study addresses these criticisms in order to provide a clearer test of the IHT theory. Schizophrenics, depressives, normal controls, and normals with schizoid tendencies were assessed on five measures of IHT (verbal and nonverbal dichotic listening, intermanual transfer, bimanual block design, finger sequence repetition) and two measures of unilateral hemispheric processing (lateral eye movements, auditory thresholds). Results consistently failed to support an IHT deficit interpretation of schizophrenia. Schizoid normals had a significantly greater right-ear advantage on verbal dichotic listening than both psychiatric groups, a result suggesting enhanced left-hemisphere activation in schizoid normals. It is concluded that the IHT theory requires stronger empirical substantiation than has been obtained to date to warrant further consideration as a central theory of schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
42.
Barcelos RC Benvegnú DM Boufleur N Pase C Teixeira AM Reckziegel P Emanuelli T da Rocha JB Bürger ME 《Lipids》2011,46(2):143-149
Fish oil (FO) supplementation could cause an increase in the concentration of plasmatic free fatty acids and, consequently,
could compete with pro-inflammatory arachidonic acid (ARA) derived from brain biomembranes metabolism in the cerebrospinal
fluid. Essential fatty acids (EFA) (n-3) have been reported by their antioxidant and neuroprotective properties, and therefore
the influence of the FO supplementation on the reserpine-induced motor disorders was studied. Wistar rats were orally treated
with FO solution for 5 days, and co-treated with reserpine (R; 1 mg/kg/mL) or its vehicle for 3 days (every other day). Reserpine-induced orofacial dyskinesia and catalepsy (P < 0.05) were prevented by FO (P < 0.05). Biochemical evaluations showed that reserpine treatment increased the lipid peroxidation in the cortex and striatum
(P < 0.05), while the FO supplementation prevented this oxidative effect in both brain regions (P < 0.05). Our results showed the protective role of FO in the brain lipid membranes, reinforcing the beneficial effect of
n-3 fatty acids in the prevention of degenerative and motor disorders. 相似文献
43.
Fuster G Almendro V Fontes-Oliveira CC Toledo M Costelli P Busquets S López-Soriano FJ Argilés JM 《Lipids》2011,46(11):1033-1042
Interleukin-15 (IL-15) is an anabolic factor for skeletal muscle and several reports have described its important role as
a regulator of energy homeostasis. In this study, we analyzed the effects of IL-15 on adipocyte differentiation using the
3T3-L1 preadipose cell line. The data show that IL-15 tends to reduce the rate of adipocyte proliferation, induces apoptosis,
and partially stops differentiation. The signaling molecules behind these actions of the cytokine on adipose cells are: p42/p44
MAPK (which seem to be associated with the reduced rate of proliferation induced by the cytokine), STAT5 (which is related
to the actions of IL-15 on differentiation), and SAPK/JNK (which are related to the increased apoptosis induced by IL-15).
In conclusion, using the 3T3-L1 adipocyte cell line, the results presented here show that IL-15 exerts important effects on
differentiation, proliferation and apoptosis. Altogether, the results presented here reinforce the idea that IL-15 is an important
mediator that regulates adipose size and, therefore, the role of the cytokine in affecting body weight and obesity deserves
additional studies. 相似文献
44.
Polyana Cristine Tizioto Caio Fernando Gromboni Ana Rita de Araujo Nogueira Marcela Maria de Souza Maurício de Alvarenga Mudadu Patricia Tholon Antônio do Nascimento Rosa Rymer Ramiz Tullio Sérgio Raposo Medeiros Renata Tieko Nassu Luciana Correia de Almeida Regitano 《Meat science》2014
Calcium (Ca) and potassium (K) are essential nutrients in animal nutrition. Furthermore, the Ca content can influence meat tenderness because it is needed by the proteolytic system of calpains and calpastatins, major factors in postmortem tenderization of skeletal muscles. K content, which is needed for muscle contraction, can also affect meat tenderness. This study showed that K positively affects the Warner–Bratzler shear force (WBSF), measured at 14 days of meat aging, which means that higher levels of K are related to lower meat tenderness. Additionally, a significant effect (P ≤ 0.015) of a SNP in the calcium-activated neutral protease 1 (CAPN1) gene on Ca content was observed. Metal content in beef can affect not only nutritional values but also meat quality traits. Part of this effect may be related to variation in specific genes. 相似文献
45.
Lilian Vanessa Rossa Lisete Cristine Scienza Ademir Jos Zattera 《Polymer Composites》2013,34(4):450-456
Poly(hydroxybutyrate‐co‐valerate) (PHBV), a biodegradable polymer produced from a renewable microbiological source, was reinforced with varying amounts of curauá fibers (CFs). The composites were produced using a twin‐screw extrusion and injection process. Scanning electron microscopy showed poor adhesion between the matrix and fiber; however, mechanical testing showed that the addition of the fiber improved the mechanical properties. Composites with 20 and 30 wt% CF displayed the best properties; however, because of the difficulties in processing composites with a CF content of 30 wt%, it was concluded that the ideal content of CF was 20 wt%. POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers 相似文献
46.
Chillrud SN Bopp RF Simpson HJ Ross JM Shuster EL Chaky DA Walsh DC Choy CC Tolley LR Yarme A 《Environmental science & technology》1999,33(5):657-662
It is generally assumed that declining atmospheric lead concentrations in urban centers during the 1970s and 1980s were due almost entirely to the progressive introduction of unleaded gasoline. However, most environmental data are from monitoring programs that began only two to three decades ago, which limits their usefulness. Here, trace metal and radionuclide data from sediment cores in Central Park Lake provide a record of atmospheric pollutant deposition in New York City through the 20th century, which suggests that leaded gasoline combustion was not the dominant source of atmospheric lead for NYC. Lead deposition rates, normalized to known Pb-210 atmospheric influxes, were extremely high, reaching maximum values (>70 μg cm(-2) yr(-1)) from the late 1930s to early 1960s, decades before maximum emissions from combustion of leaded gasoline. Temporal trends of lead, zinc, and tin deposition derived from the lake sediments closely resemble the history of solid waste incineration in New York City. Furthermore, widespread use of solid waste incinerators in the United States and Europe over the last century suggests that solid waste incineration may have provided the dominant source of atmospheric lead and several other metals to many urban centers. 相似文献
47.
Larissa Cicianny Luz Ferreira de Araújo Taisa Cristine de Moura Dantas Aruzza Mabel de Morais Araújo Amanda Duarte Gondim Valter José Fernandes Júnior Antonio Souza de Araújo 《Petroleum Science and Technology》2017,35(13):1396-1402
In research for materials that can be applied in processing heavy oil (petroleum), this work proposes to synthesize mesoporous heterogeneous catalysts, type SBA-15, with the addition of cerium metal and aluminum. These catalysts were characterized by X-ray diffraction, scanning electron micrographs coupled to energy dispersive spectrometry, spectroscopy in the infrared region by Fourier transform, N2 adsorption and desorption and thermal analysis-thermogravimetry. Thermal tests were performed to evaluate the thermal and catalytic degradation process with a sample of heavy oil (°API = 14). Through the non-isothermal kinetic model of Ozawa Flynn Wall (OFW) some parameters for determining the apparent activation energy of decomposition were obtained. The petroleum with 12% of Ce5Al50SBA-15 showed a catalytic activity for this material. It has been seen that there was a decrease in the Ea in model free of the order from 89.0 to 104.9 kJ mol?1 in α = 50% ± 10%, and it was repeated from the first percentage until the last showing performance of Ce5Al50SBA-15 as a catalyst. 相似文献
48.
49.
Fabio Caixeta Nunes Kairin Cristine Ribeiro Fabio André Martini Breno Rocha Barrioni João Paulo Ferreira Santos Benjamim Melo Carvalho 《应用聚合物科学杂志》2021,138(45):51342
The use of biodegradable polymers has grown exponentially due to their lower environmental impact when compared to conventional polymers. In this sense, biocomposites are an alternative due to their promising properties, maintaining biodegradability. For this purpose, in the present study, a biodegradable biocomposite of PBAT (poly [butylene adipate co-terephthalate]) and PLA (polylactide) blend containing cellulose nanocrystals (CNC) were obtained, using polyethylene grafted with maleic anhydride (PE-g-MA) as a coupling agent. Seven formulations were produced by extrusion and had their structure, morphology, thermal, and rheological properties analyzed. The results showed a significant improvement of adhesion among the components using PE-g-MA as a coupling agent. Moreover, CNC and PE-g-MA increased the PLA crystallinity degree and reduced the complex viscosity. These results are unprecedented in the literature using these compositions and extrusion processing conditions. Therefore, these new insights provide a vast horizon for the use of biodegradable mixtures using PBAT/PLA and CNC. 相似文献
50.
Gabriel CG Corso AC Caldeira GV Gimeno SG Schmitz Bde A de Vasconcelos Fde A 《Archivos latinoamericanos de nutrición》2010,60(4):332-339
The purpose of this study is to determine the correlation of socioeconomic, dietary, and anthropometric-nutritional variables of parents and their children to overweight (including obesity) in schoolchildren in Santa Catarina State, Brazil. This is a transversal study conducted on 4,964, 6 to 10-year-old schoolchildren registered in 345 Santa Catarina elementary schools. The following data were acquired: the children's current weight and height, birth weight and length, duration of breastfeeding, age at which water, herbal tea and other foods were introduced to their diet; parental income, education level, age, weight and height were also obtained. The prevalence of overweight and obese children were estimated by point and by interval with a 95% confidence; prevalence rates were obtained based on the Poisson model. An hierarchical approach was used, in which variables were adjusted within blocks and included in the model when they presented p < 0.05 at the outcome (overweight including obesity). The results indicate that 47.8% of the subjects were male. The prevalence of overweight and obese students was 15.4% (C195%: 14.4%-16.5%) and 6.1% (C195%: 5.4%-6.7%) respectively and were statistically similar among sexes and age ranges. BMI values were higher in males and among older children (p < 0.05). After adjustment within and among blocks, the variables per capita household income and parents' BMI values remained associated with overweight (including obesity). Overweight (including obesity) in schoolchildren is associated with a higher per capita household income and parental overweight and obesity. 相似文献