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51.
Chylopericardial tamponade occurs very rarely after heart surgery. It may be the result of lymphatic duct interruption during mammary artery harvest, division of a large thymic remnant, or thrombosis of the subclavian or internal jugular vein by an indwelling central line. Although relatively straightforward when the pericardial aspirate has the usual milky appearance, the correct diagnosis can easily be overlooked particularly early after surgery when the patient is still fasting. We present a case report that illustrates the importance of sending all aspirates for chemical analysis irrespective of their color to arrive at the correct diagnosis and institute the appropriate medical management of this rare condition.  相似文献   
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Three young gibbons, who had minimal previous social contact with each other, were released together in a semi-natural environment. The individual and social behavior of the gibbons paralleled that of gibbons in the wild: of the total daytime, 71% was spent in foraging activities, 20% in social interaction, and 9% in inactivity.The tendency toward group formation proved strong in these gibbons; they were together an average of 68% of the time following their release. Group maintenance seemed based on a sharing of the dominance role for various activities, either equally among the three or in the form of a pair (the male and one of the females) being co-dominant. The male and small female became gradually isolated from the large female. Reciprocal initiation of sexual exploration and play were related to this pairing.The results of discrete activity observations by the simple method of simultaneously recording geographical location and activity of each gibbon, plus the continuous observation of social behavior, were remarkably consistent with gibbon observational data in an artificial setting and those obtained in long-term field investigations. In addition, the methodology permitted an analysis of some of the finer aspects of social behavior.  相似文献   
54.
Addition of methylmagnesium iodide to methyl 2,3,6-trideoxy-3-trifluoro-acetamido-α-l-threo-hexopyranosid-4-ulose (3) gave methyl 2,3,6-trideoxy-4-C-methyl-3-trifluoroacetamido-α-l-lyxo-hexopyranoside (4) and its l-arabino analogue, depending upon the reaction temperature and the solvent. The corresponding 4-O-methyl derivatives were obtained by treatment of 4 and 5 with diazomethane in the presence of boron trifluoride etherate. Treatment of 4 with thionyl chloride, followed by an alkaline work-up, gave methyl, 2,3,4,6-tetradeoxy-4-C-methylene-3-trifluoro-acetamido-α-l-threo-hexopyranoside (8), which was stereoselectively reduced to methyl 2,3,4,6-tetradeoxy-4-C-methyl-3-trifluoroacetamido-α-l-arabino-hexopyranoside. Epoxidation of 8 with 3-chloroperoxybenzoic acid gave the corresponding 4,41-anhydro-4-C-hydroxymethyl-l-lyxo derivative (10), which was also prepared by treatment of 3 with diazomethane. Azidolysis of 10, followed by catalytic hydrogenation and N-trifluoroacetylation, gave methyl 2,3,6-trideoxy-3-trifuloroacetamido-4-C-trifluoroacetamidomethyl-α-l-lyxo-hexopyranoside.  相似文献   
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Hypothesizing that UCP2 may influence insulin secretion by modifying the ATP/ADP ratio within pancreatic islets, we have investigated the expression of intraislet UCP2 gene in rats showing insulin oversecretion (non-diabetic Zucker fa/fa obese rats, glucose-infused Wistar rats) or insulin undersecretion (fasting and mildly diabetic rats). We found that in Zucker fa/fa obese rats, hyperinsulinemia (1222 ± 98 pmol/1 vs. 128 ± 22 pmol/1 in lean Zucker rats) was accompanied by a significant increase in UCP2 mRNA levels. In rat submitted to a 5 day infusion with glucose, hyperinsulinemia (1126 ± 101 pmol/l vs. 215 ± 25 pmol/1 in Wistar control rats), coincided with an enhanced intraislet UCP2 gene expression, whereas a 8h or a 2 day-infusion did not induce significant changes in UCP2 mRNA expression. In rats made hypoinsulinemic and mildly diabetic by the injection of a low dose of streptozotocin, and in 4-day-fasting rats (plasma insulin 28 ± 5 pmol/1) UCP2 gene expression was sharply decreased. A 3-day-fast was ineffective. The data show the existence of a time-dependent correlation between islet mRNA UCP2 and insulin that may be interpreted as an adaptative response to prolonged insulin excess.  相似文献   
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Background

We undertook ethnobotanical and ecological studies on fodder plants grazed by cattle across Benin national area. The study aims to ascertain the top priority fodder plants in order to catalogue the indigenous knowledge regarding their use.

Methods

Data were collected through semi-structured interviews and covered 690 breeders and 40 days of pasture walk. These were analysed using similarity index of Jaccard (IS), relative frequency citation (RFC) and fodder value during pasture walk (FVPW).

Results

We documented a total of 257 fodder plant species, of which 116 recorded during ethnobotanical investigations and 195 during pasture walk. These species belong to 181 genera and 54 families. Both methods shared 52 species. Leaves (58%) and leafy stem (28%) were the most grazed parts of plant. The most common species used as fodder included Andropogon gayanus, Panicum maximum, Pterocarpus erinaceus and Flueggea virosa. The top species with a highest FVPW were Panicum maximum and Pterocarpus erinaceus. A total of 16 species were considered as top fodder plants in Benin.

Conclusions

The wide diversity of plants reported indicates that there is a number of promising fodder species in the flora of Benin. The insight gained in this study relating to bovine feeds could guide in the selection and introduction of feed innovations that could improve livestock production.
  相似文献   
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Background

There is growing debate on the use of drugs that promote cognitive enhancement. Amphetamine-like drugs have been employed as cognitive enhancers, but they show important side effects and induce addiction. In this study, we investigated the use of modafinil which appears to have less side effects compared to other amphetamine-like drugs. We analyzed effects on cognitive performances and brain resting state network activity of 26 healthy young subjects.

Methodology

A single dose (100 mg) of modafinil was administered in a double-blind and placebo-controlled study. Both groups were tested for neuropsychological performances with the Raven’s Advanced Progressive Matrices II set (APM) before and three hours after administration of drug or placebo. Resting state functional magnetic resonance (rs-FMRI) was also used, before and after three hours, to investigate changes in the activity of resting state brain networks. Diffusion Tensor Imaging (DTI) was employed to evaluate differences in structural connectivity between the two groups. Protocol ID: Modrest_2011; NCT01684306; http://clinicaltrials.gov/ct2/show/NCT01684306.

Principal Findings

Results indicate that a single dose of modafinil improves cognitive performance as assessed by APM. Rs-fMRI showed that the drug produces a statistically significant increased activation of Frontal Parietal Control (FPC; p<0.04) and Dorsal Attention (DAN; p<0.04) networks. No modifications in structural connectivity were observed.

Conclusions and Significance

Overall, our findings support the notion that modafinil has cognitive enhancing properties and provide functional connectivity data to support these effects.

Trial Registration

ClinicalTrials.gov NCT01684306 http://clinicaltrials.gov/ct2/show/NCT01684306.  相似文献   
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Urban metabolism (UM) is a way of characterizing the flows of materials and energy through and within cities. It is based on a comparison of cities to living organisms, which, like cities, require energy and matter flows to function and which generate waste during the mobilization of matter. Over the last 40 years, this approach has been applied in numerous case studies. Because of the data‐intensive nature of a UM study, however, this methodology still faces some challenges. One such challenge is that most UM studies only present macroscopic results on either energy, water, or material flows at a particular point in time. This snapshot of a particular flow does not allow the tracing back of the flow's evolution caused by a city's temporal dynamics. To better understand the temporal dynamics of a UM, this article first presents the UM for Brussels Capital Region for 2010, including energy, water, material, and pollution flows. A temporal evaluation of these metabolic flows, as well as some urban characteristics starting from the seminal study of Duvigneaud and Denayer‐De Smet in the early 1970s to 2010, is then carried out. This evolution shows that Brussels electricity, natural gas, and water use increased by 160%, 400%, and 15%, respectively, over a period of 40 years, whereas population only increased by 1%. The effect of some urban characteristics on the UM is then briefly explored. Finally, this article succinctly compares the evolution of Brussels’ UM with those of Paris, Vienna, Barcelona, and Hong Kong and concludes by describing further research pathways that enable a better understanding of the complex functioniong of UM over time.  相似文献   
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