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61.
This paper aims to assess to what degree and in what way the brood chamber affects the pollen content of the honey. Twenty-nine pieces of comb containing only honey were cut from different frames of hives. The percentage of cells in each frame occupied by the brood chamber and the distance between these cells and the cut piece were recorded. A honey sample was extracted from each comb piece, avoiding any contamination with pollen, its sediment examined under the microscope and its botanical constituents identified and counted. The results show that the pollen content of honey was higher in samples from frames containing brood or pollen cells; in these samples the pollen content was positively correlated with the amount of these cells in the frame and the proximity of the honey to them. The proportion of pollen grains from principally nectariferous plants was lower in honeys with a high pollen content. 相似文献
62.
Diane Macquart de Terline Gilles Hejblum Christine Fernandez Ariel Cohen Marie Antignac 《PloS one》2016,11(1)
Background
Oral anticoagulation therapy is increasingly used for the prevention and treatment of thromboembolic complications in various clinical situations. Nowadays, education programs for patients treated with anticoagulants constitute an integrated component of their management. However, such programs are usually based on the healthcare providers’ perceptions of what patients should know, rather than on patients’ preferences.Objective
To investigate patients’ viewpoints on educational needs and preferred modalities of information delivery.Methods
We conducted an observational study based on a self-administered questionnaire. To explore several profiles of patients, the study was designed for enrolling patients in two settings: during outpatient consultations in a cardiology department (Saint Antoine Hospital, Paris, France) and in community pharmacies throughout France.Results
Of the 371 patients who completed the questionnaire, 187 (50.4%) were recruited during an outpatient consultation and 184 (49.6%) were recruited in community pharmacies. 84.1% of patients were receiving a vitamin K antagonist and 15.6% a direct oral anticoagulant. Patients ranked 16 of 21 (76.2%) questionnaire items on information about their treatment as important or essential; information on adverse effects of treatment was the highest ranked domain (mean score 2.38, 95% CI 2.30–2.46). Pharmacists (1.69, 1.58–1.80), nurses (1.05, 0.95–1.16), and patient associations (0.36, 0.29–0.44), along with group sessions (0.85, 0.75–0.95), the internet (0.77, 0.67–0.88), and delivery of material at the patient’s home (1.26, 1.14–1.38), were ranked poorly in terms of delivering educational material.Conclusion
This study revealed substantial discrepancies between patient preferences and current educational programs. These findings should be useful for tailoring future educational programs that are better adapted to patients, with a potential associated enhancement of their effectiveness. 相似文献63.
Mu-calpain is functionally required for alpha-processing of Alzheimer's beta-amyloid precursor protein 总被引:2,自引:0,他引:2
Alzheimer's beta-amyloid precursor protein (APP) is normally processed by an unidentified alpha-secretase. A unique feature of this protease is its high sensitivity to phorbol esters, yet the mechanism involved is unclear. We have previously reported that phorbol 12,13-dibutyrate (PDBu) activates calpain, a Ca2+-dependent protease, and PDBu-induced release of APPs (secreted APP) is sensitive to calpain inhibitors, suggesting that calpain is involved in APP alpha-processing. In the present study, we found that PDBu markedly promoted the expression of both mu- and m-calpains in cultured fibroblasts. Dose-response and time course studies revealed that mu-calpain was more sensitive to PDBu than m-calpain and the temporal course of the mu-calpain change coincides better with that of APPs release. Moreover, the stimulatory effect of PDBu on mu-calpain was selectively blocked by mu-calpain-specific siRNA (small interference RNA) and the blockage was accompanied by a concomitant decrease in APPs release. In contrast, m-calpain siRNA did not affect APPs release significantly. Measurement of amyloid beta protein (Abeta) release in the mu-calpain siRNA-treated cells indicated that Abeta40 and Abeta42 levels inversely changed in relation to APPs, and the changes in Abeta42 were more prominent than in Abeta40. Together, these data suggest that calpain, particularly mu-calpain, is a potential candidate for alpha-secretase in the regulated APP alpha-processing, and that changes in this protease can affect the outcome of the overall APP processing. 相似文献
64.
65.
Simple scaling of photosynthesis from leaves to canopies without the errors of big-leaf models 总被引:24,自引:0,他引:24
In big-leaf models of canopy photosynthesis, the Rubisco activity per unit ground area is taken as the sum of activities per unit leaf area within the canopy, and electron transport capacity is similarly summed. Such models overestimate rates of photosynthesis and require empirical curvature factors in the response to irradiance. We show that, with any distribution of leaf nitrogen within the canopy (including optimal), the required curvature factors are not constant but vary with canopy leaf area index and leaf nitrogen content. We further show that the underlying reason is the difference between the time-averaged and instantaneous distributions of absorbed irradiance, caused by penetration of sunflecks and the range of leaf angles in canopies. These errors are avoided in models that treat the canopy in terms of a number of layers – the multi-layer models. We present an alternative to the multi-layer model: by separately integrating the sunlit and shaded leaf fractions of the canopy, a single layered sun/shade model is obtained, which is as accurate and simpler. The model is a scaled version of a leaf model as distinct from an integrative approach. 相似文献
66.
CECILE POMPORT-CASTILLON BERNARD ROMESTAND JOHAN F. DE JONCKHEERE 《The Journal of eukaryotic microbiology》1997,44(6):540-544
ABSTRACT. The SSUrDNA and the ITS of different microsporidia from eight fishes, four insects and a shrimp were amplified and digested with restriction enzymes. The generated riboprints suggest a close evolutionary relationship between Glugea americanus and Spraguea lophii suggesting that Glugea americanus should be renamed Spraguea americanus and that the tissue infected and host origin should be considered of greater taxonomic importance for defining a genus than previously considered. Phylogenetic analysis of the riboprints demonstrates an unidentified microsporidium from a bumper fish ( Chloroscombrus chrysurus ) is related although not identical to Microgemma oviodea , a parasite from red band fish. We were also able to distinguish between Glugea anomala and Glugea atherinae and Glugea stephani but were not able to differenciate among the latter two. Insects isolates, Nosema costelytrae, N. bombycis, N. trichoplusiae, Nosema sp. and a shrimp isolate, Agmasoma penaei , are not related to the fish isolates. 相似文献
67.
N. Messal N. Fernandez S. Dayot V. Gratio P. Nicole C. Prochasson I. Chantret G. LeGuilloux A. Jarry A. Couvelard X. Tréton T. Voisin E. Ogier-Denis A. Couvineau 《生物化学与生物物理学报:疾病的分子基础》2018,1864(11):3618-3628
Orexins (orexin-A and orexin-B) are hypothalamic peptides that are produced by the same precursor and are involved in sleep/wake control, which is mediated by two G protein-coupled receptor subtypes, OX1R and OX2R. Ulcerative colitis (UC) is an inflammatory bowel disease, (IBD) which is characterized by long-lasting inflammation and ulcers that affect the colon and rectum mucosa and is known to be a significant risk factor for colon cancer development. Based on our recent studies showing that OX1R is aberrantly expressed in colon cancer, we wondered whether orexin-A could play a role in UC. Immunohistochemistry studies revealed that OX1R is highly expressed in the affected colonic epithelium of most UC patients, but not in the non-affected colonic mucosa. Injection of exogenous orexin-A specifically improved the inflammatory symptoms in the two colitis murine models. Conversely, injection of inactive orexin-A analog, OxB7–28 or OX1R specific antagonist SB-408124 did not have anti-inflammatory effect. Moreover, treatment with orexin-A in DSS-colitis induced OX1R?/? knockout mice did not have any protective effect. The orexin-A anti-inflammatory effect was due to the decreased expression of pro-inflammatory cytokines in immune cells and specifically in T-cells isolated from colonic mucosa. Moreover, orexin-A inhibited canonical NFκB activation in an immune cell line and in intestinal epithelial cell line. These results suggest that orexin-A might represent a promising alternative to current UC therapies. 相似文献
68.
Monika Oláhová Wan Hee Yoon Kyle Thompson Sharayu Jangam Liliana Fernandez Jean M. Davidson Jennifer E. Kyle Megan E. Grove Dianna G. Fisk Jennefer N. Kohler Matthew Holmes Annika M. Dries Yong Huang Chunli Zhao Kévin Contrepois Zachary Zappala Laure Frésard Daryl Waggott Matthew T. Wheeler 《American journal of human genetics》2018,102(3):494-504
69.
Maternal Metabolic Health Parameters During Pregnancy in Relation to Early Childhood BMI Trajectories 下载免费PDF全文
70.