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71.
Adolescent cannabis use is associated with working memory impairment. The present randomized controlled trial assigned adolescents ages 14 to 21 enrolled in cannabis use treatment to receive either working memory training (experimental group) or a control training (control group) as an adjunctive treatment. Cognitive function, drug use, and other outcomes were assessed before and after training. We observed few differences in cognitive, functional, or self-reported drug use outcomes as a function of training group, although tetrahydrocannabinol (THC) urinalysis results favored the experimental group. These findings are similar to previous studies in substance users, which have shown limited transfer effects for working memory training.  相似文献   
72.
A new scaling approach has been demonstrated for particle size reduction of an active pharmaceutical ingredient (API) in toothed rotor-stator wet mills for a wide range of wet milling conditions and scales. Compound A was crystallized by a cooling crystallization protocol in ethanol and wet milled with 2 types of lab scale mills and 1 pilot plant mill. The particle size was analyzed by FBRM (focused beam reflectance measurement), static light scattering and optical microscopy. The correlation between particle size and the energy input calculations, tailored for the toothed rotor-stator wet mill, had R2 = 0.90 on a logarithmic plot. The new scaling approach forms the basis to correlate API particle size to energy input in toothed rotor-stator wet mills by accounting for wet mill tooth configuration and geometry, rotor tip speed and the probabilistic effects of collision such as shear frequency and slurry residence time.  相似文献   
73.
Individuals subjected to acceleration forces in motor vehicle accidents often exhibit the postconcussive syndrome and, upon examination, neuropsychological impairment. Brain injury and particular variables relating to nonimpact intracranial brain movement are reviewed. Brain injury in man can occur through exposure to acceleration forces without direct impact to the head or loss of consciousness. Hence, there are clear grounds for the neuropsychological study of victims of acceleration forces. Moreover, as with mild head injury, adequate regard for the variables of age, previous head injury, premorbid adaptive ability, socioeconomic status, motivation, and test sensitivity may assist in clarifying the specific problems in adaptation encountered by this clinical population. Clinical experience suggests that acceleration forces adversely affect attention (especially at older age levels), learning, and conceptual flexibility.  相似文献   
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75.
This study analyzes mothers’ preference of a future primary caregiver by using within-family analysis approach in the context of Sundanese population in rural West Java, Indonesia. This is a cross-sectional study involving healthy mothers (60–69 years old) with a perfect score of Instrumental Activity of Daily Living (IADL), and who had at least two living children. The within-family analysis of a selection of future caregivers was conducted based on the report from 177 mothers of their 904 children using multilevel modeling with binomial outcome. Being a daughter, older, emotionally the closest to the mother, having supported the mother in the past, being perceived as future bequest receiver, and being geographically closer to mother increased the chance of being selected as preferred future primary caregivers. There were also cross-level effects of socioeconomic status (SES) on the selection of future primary caregivers by mothers, where poor mothers tend to pick poor children as their future primary caregivers. The results were contrasted to the findings from a similar study conducted in the United States. In addition, the importance of knowledge about future care preference and its implications for intervention is discussed.  相似文献   
76.

Aims/hypothesis  

Adiponectin and leptin are negatively and positively correlated with human obesity respectively, and have both been shown to regulate energy metabolism in skeletal muscle. However, little is known about their signalling and functional crosstalk. Here we investigated the effects of leptin on metabolic actions of (1) globular adiponectin (gAd) and (2) full-length adiponectin (fAd) in L6 cells.  相似文献   
77.
It was previously reported that treatment with the sulfated polysaccharide fucoidan or the structurally similar dextran sulfate increased circulating mature white blood cells and hematopoietic progenitor/stem cells (HPCs) in mice and nonhuman primates; however, the mechanism mediating these effects was unclear. It is reported here that plasma concentrations of the highly potent chemoattractant stromal-derived factor 1 (SDF-1) increase rapidly and dramatically after treatment with fucoidan in monkeys and in mice, coinciding with decreased levels in bone marrow. In vitro and in vivo data suggest that the SDF-1 increase is due to its competitive displacement from heparan sulfate proteoglycans that sequester the chemokine on endothelial cell surfaces or extracellular matrix in bone marrow and other tissues. Although moderately increased levels of interleukin-8, MCP1, or MMP9 were also present after fucoidan treatment, studies in gene-ablated mice (GCSFR(-/-), MCP1(-/-), or MMP9(-/-)) and the use of metalloprotease inhibitors do not support their involvement in the concurrent mobilization. Instead, SDF-1 increases, uniquely associated with sulfated glycan-mobilizing treatments and not with several other mobilizing agents tested, are likely responsible. To the authors' knowledge, this is the first published report of disrupting the SDF-1 gradient between bone marrow and peripheral blood through a physiologically relevant mechanism, resulting in mobilization with kinetics similar to other mobilizing CXC chemokines. The study further underscores the importance of the biological roles of carbohydrates.  相似文献   
78.
79.
Tracheal instillation of pentamidine in a surfactant vehicle may be an effective direct method of antibiotic delivery to the lungs. In 10 healthy hamsters, we compared the pulmonary distribution of 99mTc sulfur colloid (TcSC) mixed with pentamidine, using as a vehicle either surfactant (n = 5) or saline (n = 5). Each animal was instilled with 0.25 ml/kg of suspension containing 0.0018 mCi TcSC and pentamidine mixed with either surfactant or saline. After 4 h of spontaneous respiration, the lungs were excised, inflated to TLC, dried, and sliced into 3-mm cross sections from apex to base. Autoradiographs were examined to evaluate 99mTc distribution. The surfactant group had detectable radioactivity in 93% of all slices compared with 72% in the saline group (p = 0.02). Six slices per animal (43% of total) and their corresponding autoradiographs were analyzed for distribution of radioactivity. Lung slice area was determined by planimetry, and autoradiograph area was determined by video densitometry. We calculated the fraction of each lung slice with detectable radioactivity. The surfactant group had 41% of the lung slice areas exposed compared with 21% in the saline group (p = 0.02). The coefficient of variation of radioactive intensities within each slice was used as an index of spatial uniformity. There was a trend towards more uniform distribution in the surfactant group, with a narrower range of variation of intensities (1.51 to 2.56) than the saline group (1.95 to 6.47). We conclude that a surfactant vehicle significantly increases airspace deposition of TcSC and pentamidine instilled intratracheally in normal hamster lungs, and may improve uniformity of spread.  相似文献   
80.
There is conflicting evidence as to whether dimethyl sulfoxide (DMSO) can reversibly open the blood-brain barrier and augment brain uptake of water-soluble compounds, including anticancer agents. To investigate this, 125I-human serum albumin, horseradish peroxidase, or the anticancer drug melphalan was administered iv to rats or mice, either alone or in combination with DMSO. Some animals received an additional ip priming dose of DMSO. The regional brain concentrations of each substance were measured after the animals were killed. DMSO administration did not significantly increase the brain uptake of any of the compounds as compared to control uptakes. These results do not support prior reports that DMSO increases the permeability of water-soluble agents across the blood-brain barrier.  相似文献   
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