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51.
Nadine?AME?van der BeekEmail author Juna?M?de Vries Marloes?LC?Hagemans Wim?CJ?Hop Marian?A?Kroos John?HJ?Wokke Marianne?de Visser Baziel?GM?van Engelen Jan?BM?Kuks Anneke?J?van der Kooi Nicolette?C?Notermans Karin?G?Faber Jan?JGM?Verschuuren Arnold?JJ?Reuser Ans?T?van der Ploeg Pieter?A?van Doorn 《Orphanet journal of rare diseases》2012,7(1):88
Background
Due partly to physicians’ unawareness, many adults with Pompe disease are diagnosed with great delay. Besides, it is not well known which factors influence the rate of disease progression, and thus disease outcome. We delineated the specific clinical features of Pompe disease in adults, and mapped out the distribution and severity of muscle weakness, and the sequence of involvement of the individual muscle groups. Furthermore, we defined the natural disease course and identified prognostic factors for disease progression.Methods
We conducted a single-center, prospective, observational study. Muscle strength (manual muscle testing, and hand-held dynamometry), muscle function (quick motor function test), and pulmonary function (forced vital capacity in sitting and supine positions) were assessed every 3–6 months and analyzed using repeated-measures ANOVA.Results
Between October 2004 and August 2009, 94 patients aged between 25 and 75 years were included in the study. Although skeletal muscle weakness was typically distributed in a limb-girdle pattern, many patients had unfamiliar features such as ptosis (23%), bulbar weakness (28%), and scapular winging (33%). During follow-up (average 1.6 years, range 0.5-4.2 years), skeletal muscle strength deteriorated significantly (mean declines of ?1.3% point/year for manual muscle testing and of ?2.6% points/year for hand-held dynamometry; both p<0.001). Longer disease duration (>15 years) and pulmonary involvement (forced vital capacity in sitting position <80%) at study entry predicted faster decline. On average, forced vital capacity in supine position deteriorated by 1.3% points per year (p=0.02). Decline in pulmonary function was consistent across subgroups. Ten percent of patients declined unexpectedly fast.Conclusions
Recognizing patterns of common and less familiar characteristics in adults with Pompe disease facilitates timely diagnosis. Longer disease duration and reduced pulmonary function stand out as predictors of rapid disease progression, and aid in deciding whether to initiate enzyme replacement therapy, or when.52.
Epiphytic Refugium: Are Two Species of Invading Freshwater Bivalves Partitioning Spatial Resources? 总被引:1,自引:0,他引:1
Thomas P. Diggins Michael Weimer Kenton M. Stewart Robert E. Baier Anne E. Meyer Robert F. Forsberg Michael A. Goehle 《Biological invasions》2004,6(1):83-88
Enumeration of benthic (bottom dwelling) and epiphytic (attached to plants) zebra and quagga mussels (Dreissena polymorpha and D. bugensis, respectively) at Lake Erie near-shore sites in fall of 2000 revealed an unexpected prevalence of the zebra mussel on submerged
plants. Even at Buffalo, New York, USA, where benthic dreissenids have been 92–100% quagga mussel since 1996, zebra mussels
constituted 30–61% of epiphytes numerically. This may reflect a partitioning of settling space consistent with interspecific
competition. A seasonal epiphytic refugium might allow the zebra mussel to persist even where the benthos is almost exclusively
quagga mussel.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
53.
54.
B Bauer N Krumb?ck F Fresser F Hochholdinger M Spitaler A Simm F Uberall B Schraven G Baier 《The Journal of biological chemistry》2001,276(34):31627-31634
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Callus cultures from cotyledons of Cassia angustifolia were shown to contain dianthrones. Proof of their structures was obtained by co-chromatography (TLC), oxidative cleavage and UV analysis. The basic components chrysophanol, physcion, rheum emodin, aloe emodin and rhein have been isolated and identified by UV and IR analysis. 相似文献
59.
Background
OMA is a project that aims to identify orthologs within publicly available, complete genomes. With 657 genomes analyzed to date, OMA is one of the largest projects of its kind. 相似文献60.
Rodland David L.; Schone Bernd R.; Baier Sven; Zhang Zengjie; Dreyer Wolfgang; Page Nicholas A. 《Journal of Molluscan Studies》2009,75(1):51-57
Physiologically-driven rhythms in bivalve molluscs are predictedto vary as a function of metabolic rate and temperature, incontrast to genetically predisposed biological clocks. Theserhythms can be evaluated using long-term video monitoring techniquesunder controlled conditions in laboratory aquaria. The bivalvesAnodonta cygnea and Margaritifera falcata were used to evaluatethe effect of temperature on rhythms in gape and the formationof siphons at the mantle edge. Frequency and duration of shellclosure vary with temperature in both species, but with differentresponses. Mean duration of intervals of valve closure decreasesas temperature rises in both species, and is consistent withphysiological limitation by increased biological oxygen demand.For A. cygnea, cumulative gape duration peaks at 25°C, withless time spent closed than at any other temperature, but increasingtemperatures correspond to an increase in gape frequency witha strong increase observed at 31°C. In contrast, frequencyof adduction and valve closure peak at 25°C in M. falcata,and continuous gaping is observed above 29.5°C. This physiologicalstress is consistent with evidence from sclerochronologically-calibratedstable isotope studies of shells, where growth breaks in manymarine taxa coincide with maximum temperatures above 31°Cas derived for 18Ocarbonate. The results of this study suggestthat these growth breaks may be due to physiological limitationsin oxygen uptake and metabolic activity, rather than being adirect consequence of elevated temperature alone. (Received 17 March 2008; accepted 3 October 2008) 相似文献