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1.
OBJECTIVE: To assess the quantity and nature of the proteins that adsorb to hydrocephalus shunt catheters after implantation, and to determine whether sufficient could accumulate to obstruct the catheter. DESIGN: Elution of proteins from 102 explanted shunt catheters, with protein assay and electrophoresis of the eluate, and scanning electron microscopy (SEM) of the catheters. RESULTS: The amount of protein elutable was extremely low, and significant protein, apart from a thin film, was not found on SEM. Qualitative analysis disclosed that most of the adsorbed protein was albumin. CONCLUSIONS: Protein deposition on hydrocephalus catheters does not occur in sufficient quantities to cause catheter obstruction.  相似文献   
2.
When working on the synthesis of substituted cyclodextrins (CDs), the main challenge remains the analysis of the reaction media content. Our objective in this study was to fully characterise a complex isomers mixture of Lipidyl-βCDs (LipβCD) obtained with a degree of substitution 1 (DS = 1) from a one-step synthesis pathway. The benefit of tandem mass spectrometry (MS/MS) and ion mobility separation hyphenated with mass spectrometry (IM-MS) was investigated. The MS/MS fragment ion‘s relative intensities were analysed by principal component analysis (PCA) to discriminate isomers. The arrival time distribution (ATD) of each isomer was recorded using a travelling wave ion mobility (TWIM) cell allowing the determination of their respective experimental collision cross section (CCSexp). The comparison with the predicted theoretical CCS (CCSth) obtained from theoretical calculations propose a regioisomer assignment according to the βCD hydroxyl position (2, 3, or 6) involved in the reaction. These results were validated by extensive NMR structural analyses of pure isomers combined with molecular dynamics simulations. This innovative approach seems to be a promising tool to elucidate complex isomer mixtures such as substituted cyclodextrin derivatives.  相似文献   
3.
White‐light‐emitting electrochemical cells (WLECs) still represent a significant milestone, since only a few examples with moderate performances have been reported. Particularly, multiemissive white emitters are highly desired, as a paradigm to circumvent phase separation and voltage‐dependent emission color issues that are encountered following host:guest and multilayered approaches. Herein, the origin of the exclusive white ternary electroluminescent behavior of BN‐doped nanographenes with a B3N3 doping pattern (hexa‐perihexabenzoborazinocoronene) is rationalized, leading to one of the most efficient (≈3 cd A?1) and stable‐over‐days single‐component and single‐layered WLECs. To date, BN‐doped nanographenes have featured blue thermally activated delayed fluorescence (TADF). This doping pattern provides, however, white electroluminescence spanning the whole visible range (x/y CIE coordinates of 0.29–31/0.31–38 and average color rendering index (CRI) of 87) through a ternary emission involving fluorescence and thermally activated dual phosphorescence. This temperature‐dependent multiemissive mechanism is operative for both photo‐ and electroluminescence processes and holds over the device lifespan, regardless of the device architecture, active layer composition, and operating conditions. As such, this work represents a new stepping‐stone toward designing a new family of multiemissive white emitters based on BN‐doped nanographenes that realizes one of the best‐performing single‐component white‐emitting devices compared to the prior‐art.  相似文献   
4.
The possibility of applying an electromagnetic technique to locate a horizontal magnetic dipole buried in the upper layer of a 2-layer earth is studied. Results for a highly conducting substratum for various source depths and frequencies are presented.  相似文献   
5.
ABSTRACT

This paper investigates the relationship between the innovative activity of the top corporate R&D investors worldwide and their market valuation. The analysis exploits a sample of more than 1,250 publicly listed Multinational Corporations (MNCs) and their intellectual property rights (IPR) – patents and trademarks – filed between 2005 and 2012. The study contributes to the literature on the IPR-market value link by examining the premium resulting from the interactive use of different IPR. Moreover, the empirical setting allows differentiating the effects of an increase in market value derived from additional IPR (within-effects) with respect to the premium received for holding more IPR than the competitors (between-effects). The findings suggest that investors value the simultaneous use of the two IPRs and form their expectations by benchmarking firms. Finally, significant industrial specificities are observed in the individual effects of patents, trademarks and their interactions on the market value of firms.  相似文献   
6.
SETTING: Respiratory medicine wards of the University Teaching Hospital, Abidjan, C?te d'Ivoire. OBJECTIVES: To describe the spectrum of opportunistic infection among human immunodeficiency virus (HIV) infected adults hospitalised in the respiratory medicine unit in Abidjan, and the level of immunosuppression at which these diseases occur. DESIGN: Cross-sectional study. RESULTS: Overall, 75% of patients were HIV-positive: among these patients, the most frequent diagnosis was tuberculosis, in 61%, followed by bacterial pneumonia (15%), Gram-negative septicaemia (particularly non-typhoid Salmonella) (9%) and empyema (5%). Atypical pneumonias appeared to be rare. Most HIV-positive patients had CD4 counts indicative of advanced immunosuppression: 36% had CD4 counts below 100 x 10(6)/l, 19% between 100 and 199 x 10(6)/l, 29% between 200 and 499 x 10(6)/l, and 16% above 500 x 10(6)/l. Overall in-hospital mortality was 27% for HIV-positive patients and 22% for HIV-negative patients (P = 0.5). In a multivariate analysis, the strongest independent risk factors for death were cachexia (odds ratio [OR] 7.4, 95% confidence interval [CI] 2.1-26.3), male sex (OR 4.5, 95% CI 1.2-17.4) and age over 40 (OR 4.1, 95% CI 1.0-17.2). CONCLUSIONS: Tuberculosis and bacterial infections are the major causes of respiratory morbidity in immunosuppressed HIV-infected adults in this population. Efforts to improve the management of HIV-related disease need to focus on prevention and treatment of these infections.  相似文献   
7.
The effect of the frequency of the mixing of coffee cherries put out for sun drying on the kinetics of the drying, fungal growth and kinetics of ochratoxin A production was evaluated. The results showed that the more coffee cherries were mixed, the quicker they dried. This rapidity of drying led to a reduction of fungal development. Indeed, coffee cherries mixed eight and ten times a day, dried quickly and were free inside of fungi. However, infection by fungi gives little indication of ochratoxin A production in coffee cherries. Indeed, although coffee cherries mixed twice a day were more contaminated by fungi, the analysis of ochratoxin A content showed they were free of this mycotoxin. The coffee cherries that were more contaminated by ochratoxin A were those mixed four times a day (containing 0.35-5.46 µg kg-1 ochratoxin A). Ochratoxin A contamination was essentially due to the presence of Aspergillus species capable of producing ochratoxin A inside the coffee cherries.  相似文献   
8.
Coronary balloon angioplasty was performed on 33 lesions during 28 procedures in 23 octogenarians (median age 83, range 80 to 87 years) between January 1989 and December 1991. 96% of the patients had grade III-IV angina pectoris. The median left ventricular ejection fraction was 64% (range: 38-85%). Single vessel coronary artery disease was present in 43% and multivessel coronary artery disease in 57%. Angioplasty was performed on 1 vessel in 85% of the procedures and on 2 vessels in 15%. Primary angiographic success was 97% for 33 attempted lesions with one failure to recanalize an old occlusion. One patient underwent emergency intracoronary stent implantation after failed angioplasty. None underwent emergency coronary bypass surgery. One patient (4%) had a myocardial infarction and 2 patients (7%) died during hospitalization, the first because of abrupt vessel closure during angioplasty, the second due to acute retroperitoneal bleeding on the 8th day post-angioplasty while fully anticoagulated for an intracoronary stent. Follow-up (median 17, range 8 to 39 months) was obtained for all patients. Out of the 21 patients with primary angioplastic success, 3 (14%) had died (1 cardiac and 2 non-cardiac). At 1 year actuarial survival was 86%, and survival free from myocardial infarction or coronary bypass surgery was 81%. Further angioplasty for either restenosis or another lesion was performed in 5 patients (24%). These results confirm that coronary angioplasty is an effective means of controlling anginal symptoms in a selected group of severely symptomatic octogenarians. However, when complications do occur they are linked to a significant mortality rate.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
9.
Commercial edible vegetable oils in which part of their triglycerides are substituted with 1,3-diglycerides are healthier for human consumption than the original oils. This is because the human metabolism of 1,3-diglycerides is believed to occur through a distinct pathway with less probability of being deposited as fat in the body tissues. To obtain these enriched oils, conversion of triglycerides into diglycerides is carried out by glycerolysis using commercial crude glycerol containing dissolved alkali cations that homogeneously catalyze the reaction. The addition of a food production-compatible MgO as a supplementary solid basic catalyst, shortens the reaction time by half due to a combination of homogeneous and heterogeneous catalysis processes. In either homogeneously or homogeneous-heterogeneously catalyzed glycerolysis, the increase of the reaction temperature in the range of 453–493 K increases the final 1,3-diglyceride content. Furthermore, in both glycerolysis processes the triglyceride content can be decreased in more than 60% with the consequent increase of total diglycerides to 50%, 70% of which are the 1,3-isomers. The glycerolysis reaction proceeds without altering the fatty acid distribution of the original oils.  相似文献   
10.
The level of antibiotic multiresistance of Campylobacter strains from chicken was evaluated and responses to the bactericidal effects of organic acids were analyzed. Strains (76) isolated from chicken were analyzed for resistance to antibiotics and acid shock. A high strain resistance to fluoroquinolones (ciprofloxacin and nalidixic acid) was observed, with cross resistance to both drugs in 41% of strains. A low resistance was observed for amoxicillin, erythromycin, and gentamicin. Campylobacter jejuni was the most resistant species. Antibacterial activities against multiresistant Campylobacter strains were observed using acetic, citric, and ascorbic acids at minimum bactericidal concentrations (MBC) ranging from 0.3 to 3 mg/mL. Acetic acid was the most efficient acid with the lowest MBC value. However, a contact time of 4 h was required for an efficient effect against Campylobacter contaminated chicken skin. Using organic acids in the poultry production chain can reduce propagation of antibiotic multiresistant strains of Campylobacter.  相似文献   
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