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排序方式: 共有214条查询结果,搜索用时 218 毫秒
51.
52.
Østensen M Khamashta M Lockshin M Parke A Brucato A Carp H Doria A Rai R Meroni P Cetin I Derksen R Branch W Motta M Gordon C Ruiz-Irastorza G Spinillo A Friedman D Cimaz R Czeizel A Piette JC Cervera R Levy RA Clementi M De Carolis S Petri M Shoenfeld Y Faden D Valesini G Tincani A 《Arthritis research & therapy》2006,8(3):209-19
Rheumatic diseases in women of childbearing years may necessitate drug treatment during a pregnancy, to control maternal disease activity and to ensure a successful pregnancy outcome. This survey is based on a consensus workshop of international experts discussing effects of anti-inflammatory, immunosuppressive and biological drugs during pregnancy and lactation. In addition, effects of these drugs on male and female fertility and possible long-term effects on infants exposed to drugs antenatally are discussed where data were available. Recommendations for drug treatment during pregnancy and lactation are given. 相似文献
53.
Rational analyses of organelle trajectories in tobacco pollen tubes reveal characteristics of the actomyosin cytoskeleton
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To gain insight into the characteristics of organelle movement and the underlying actomyosin motility system in tobacco pollen tubes, we collected data points representing sequential organelle positions in control and cytochalasin-treated cells, and in a sample of extruded cytoplasm. These data were utilized to reconstruct approximately 900 tracks, representing individual organelle movements, and to produce a quantitative analysis of the movement properties, supported by statistical tests. Each reconstructed track appeared to be unique and to show irregularities in velocity and direction of movement. The regularity quotient was near 2 at the tip and above 3 elsewhere in the cell, indicating that movement is more vectorial in the tube area. Similarly, the progressiveness ratio showed that there were relatively more straight trajectories in the tube region than at the tip. Consistent with these data, arithmetical dissection revealed a high degree of randomlike movement in the apex, lanes with tip-directed movement along the flanks, and grain-directed movement in the center of the tube. Intercalated lanes with bidirectional movement had lower organelle velocity, suggesting that steric hindrance plays a role. The results from the movement analysis indicate that the axial arrangement of the actin filaments and performance of the actomyosin system increases from tip to base, and that the opposite polarity of the actin filaments in the peripheral (+-ends of acting filaments toward the tip) versus the central cytoplasm (+-ends of actin filaments toward to the grain) is installed within a few minutes in these tip-growing cells. 相似文献
54.
Systemic and central nervous system correction of lysosomal storage in mucopolysaccharidosis type VII mice
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Mucopolysaccharidosis (MPS) type VII patients lack functional beta-glucuronidase, leading to systemic and central nervous system dysfunction. In this study we tested whether recombinant adenovirus that encodes beta-glucuronidase (Adbetagluc), delivered intravenously and into the brain parenchyma of MPS type VII mice, could provide long-term transgene expression and correction of lysosomal distension. We also tested whether systemic treatment with the immunosuppressive anti-CD40 ligand antibody, MR-1, affected transgene expression. We found substantial plasma beta-glucuronidase activity for over 9 weeks after gene transfer in the MR-1- treated group, with subsequent decline in activity corresponding to a delayed anti-beta-glucuronidase antibody response. At 16 weeks, near wild-type amounts of beta-glucuronidase activity and striking reduction of lysosomal pathology were detected in livers from mice that had received either MR-1 cotreatment or control antibody. In the lung and kidney, beta-glucuronidase activity was markedly higher for the MR-1-treated group. beta-Glucuronidase activity in the brain persisted independently of MR-1 treatment. Activity was intense in the injected hemisphere and was also evident in the noninjected cortex and striatum, with dramatic improvements in storage deposits in areas of both hemispheres. These results indicate that prolonged enzyme expression from transgenes delivered to deficient liver and brain can mediate pervasive correction and illustrate the potential for gene therapy of MPS and other lysosomal storage diseases. 相似文献
55.
56.
van Alphen SP Engelen GJ Kuin Y van der Staak CP Derksen JJ 《Tijdschrift voor gerontologie en geriatrie》2003,34(5):208-214
A Delphi-technique was used as part of the development of a screening instrument to diagnose personality disorders in the elderly. Several statements regarding this subject were tested. Fifty-three Delphi-members, with expertise in the field of mental health services for the elderly and knowledge about the concept 'personality disorder', gave their opinion on the statements. In three successive rounds we aimed to get consensus as well as agreement on the contents of the statements. In the first round the Delphi-panel confirmed the importance of diagnosing personality disorders, with regard to individual therapy in older adults and psycho-educational activities. The DSM-IV Axis II criteria and related assessment-instruments do not take into account the emotional and social context of the elderly people. In the second round the Delphi-panel endorsed the importance of several information sources namely biographical information, informant information, behavioural observations and the reactions of the therapist himself. In the third round, 44 items considering diagnostics on personality were pro-pounded to the panel. There was agreement as well as consensus on 25 out of the 44 items. In conclusion, adjusting the DSM-IV Axis II criteria to the elderly will improve the quality of the diagnostics. Developments of a specific screening instrument for older adults probably will also increase the quality of the diagnostics. 相似文献
57.
58.
Studies of the role of the propeptides of the Arabidopsis thaliana 2S albumin. 总被引:2,自引:2,他引:0
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K D'Hondt J Van Damme C Van Den Bossche S Leejeerajumnean R De Rycke J Derksen J Vandekerckhove E Krebbers 《Plant physiology》1993,102(2):425-433
To investigate the possible roles of the Arabidopsis thaliana 2S albumin propeptides with respect to sorting, processing, and stability of the protein in plant cells, five gene constructions deleting or modifying the propeptides were made based on one of the genes encoding the Arabidopsis 2S albumin. These constructions were introduced into tobacco (Nicotiana tabacum) plants. Using subcellular fractionation and immunocytochemistry on ripe seeds, it was demonstrated that none of the propeptides was necessary for the sorting of the protein. Detailed protein-chemical analysis of the mature gene products indicated that, for all of the modified 2S albumin precursors made, the proteins were stably folded and correctly processed. However, the latter is less efficient when the internal fragment between the small and the large subunit is missing or when this internal fragment is changed. In an attempt to establish a rapid assay system for modified 2S albumin precursors, yeast cells were transformed with the same gene constructs. It was demonstrated that the processing machinery in yeast cells differs from that in plants, and, in a perhaps related observation, differences in stability of a particular modified protein were observed. 相似文献
59.
Trinette Stolle-Smits Jan Gerard Beekhuizen Matthieu T.C. Kok Mary Pijnenburg Kees Recourt Jan Derksen Alphons G.J. Voragen 《Plant physiology》1999,121(2):363-372
The changes in cell wall polysaccharides and selected cell wall-modifying enzymes were studied during the development of green bean (Phaseolus vulgaris L.) pods. An overall increase of cell wall material on a dry-weight basis was observed during pod development. Major changes were detected in the pectic polymers. Young, exponentially growing cell walls contained large amounts of neutral, sugar-rich pectic polymers (rhamnogalacturonan), which were water insoluble and relatively tightly connected to the cell wall. During elongation, more galactose-rich pectic polymers were deposited into the cell wall. In addition, the level of branched rhamnogalacturonan remained constant, while the level of linear homogalacturonan steadily increased. During maturation of the pods, galactose-rich pectic polymers were degraded, while the accumulation of soluble homogalacturonan continued. During senescence there was an increase in the amount of ionically complexed pectins, mainly at the expense of freely soluble pectins. The most abundant of the enzymes tested for was pectin methylesterase. Peroxidase, beta-galactosidase, and alpha-arabinosidase were also detected in appreciable amounts. Polygalacturonase was detected only in very small amounts throughout development. The relationship between endogenous enzyme levels and the properties of cell wall polymers is discussed with respect to cell wall synthesis and degradation. 相似文献
60.
Summary The wall ofPinus sylvestris pollen and pollen tubes was studied by electron microscopy after both rapid-freeze fixation and freeze-substitution (RF-FS) and chemical fixation. Fluorescent probes and antibodies (JIM7 and JIM5) were used to study the distribution of esterified pectin, acidic pectin and callose. The wall texture was studied on shadow-casted whole mounts of pollen tubes after extraction of the wall matrix. The results were compared to current data of angiosperms. TheP. sylvestris pollen wall consists of a sculptured and a nonsculptured exine. The intine consists of a striated outer layer, that stretches partly over the pollen tube wall at the germination side, and a striated inner layer, which is continuous with the pollen tube wall and is likely to be partly deposited after germination. Variable amounts of callose are present in the entire intine. No esterified pectin is detected in the intine and acidic pectin is present in the outer intine layer only. The wall of the antheridial cell contains callose, but no pectin is detectable. The wall between antheridial and tube cell contains numerous plasmodesmata and is bordered by coated pits, indicating intensive communication with the tube cell. Callose and esterified pectin are present in the tip and the younger parts of the pollen tubes, but both ultimately disappear from the tube. Sometimes traces in the form of bands remain present. No acidic pectin is detected in either tip or tube. The wall of the pollen tube tip has a homogenous appearance, but gradually attains a fibrillar character at aging, perhaps because of the disappearance of callose and pectin. No secondary wall formation or callose lining can be seen wilh the electron microscope. The densily of the cellulose microfibrils (CMF) is much lower in the tip than in the tube. Both show CMF in all but axial and nontransverse orientations. In conclusion,P. sylvestris and angiosperm pollen tubes share the presence of esterified pectin in the tip, the oblique orientations of the CMF, and the gradual differentiation of the pollen tube wall, indicating a possible relation to tip growth. The presence of acidic pectin and the deposition of a secondary-wall or callose layer in angiosperms but not inP. sylvestris indicales that these characteristics are not related to tip growth, but probably represent adaptations to the fast and intrastylar growth of angiosperms.Abbreviations CMF
cellulose microfibrils
- II
inner intine
- NE
nonsculptured exine
- OI
outer intine
- RF-FS
rapid-freeze fixation freeze-substitution
- SE
sculptured exine
- SER
smooth endoplasmic reliculum
- SV
secretory vesicles 相似文献