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111.
Development of biological control for plant diseases is accepted as a durable and environmentally friendly alternative for agrochemicals. Arbuscular mycorrhizal fungi (AMF), which form symbiotic associations with root systems of most agricultural, horticultural and hardwood crop species, have been suggested as widespread potential bioprotective agents. In the present study the ability of two AMF (Glomus mosseae and Glomus intraradices) to induce local or systemic resistance to Phytophthora parasitica in tomato roots have been compared using a split root experimental system. Glomus mosseae was effective in reducing disease symptoms produced by P. parasitica infection, and evidence points to a combination of local and systemic mechanisms being responsible for this bioprotector effect. The biochemical analysis of different plant defence-related enzymes showed a local induction of mycorrhiza-related new isoforms of the hydrolytic enzymes chitinase, chitosanase and beta-1,3-glucanase, as well as superoxide dismutase, an enzyme which is involved in cell protection against oxidative stress. Systemic alterations of the activity of some of the constitutive isoforms were also observed in non-mycorrhizal roots of mycorrhizal plants. Studies on the lytic activity against Phytophthora cell wall of root protein extracts also corroborated a systemic effect of mycorrhizal symbiosis on tomato resistance to Phytophthora.  相似文献   
112.
We characterized CD8(+) T cells constitutively expressing CD25 in mice lacking the expression of MHC class II molecules. We showed that these cells are present not only in the periphery but also in the thymus. Like CD4(+)CD25(+) T cells, CD8(+)CD25(+) T cells appear late in the periphery during ontogeny. Peripheral CD8(+)CD25(+) T cells from MHC class II-deficient mice also share phenotypic and functional features with regulatory CD4(+)CD25(+) T cells: in particular, they strongly express glucocorticoid-induced TNFR family-related gene, CTLA-4 and Foxp3, produce IL-10, and inhibit CD25(-) T cell responses to anti-CD3 stimulation through cell contacts with similar efficiency to CD4(+)CD25(+) T cells. However, unlike CD4(+)CD25(+) T cells CD8(+)CD25(+) T cells from MHC class II-deficient mice strongly proliferate and produce IFN-gamma in vitro in response to stimulation in the absence of exogenous IL-2.  相似文献   
113.
Neonatal screening of Duchenne Muscular Dystrophy using serum CK level measurement has been performed for 10 years in a part of the Rh?ne-Alpes area (40,000 newborns per year). This test avoids consecutive cases in an affected family by mean of an early genetic counselling. So, 10 potential DMD boys have been avoided (i.e. one out of five of the D.M.D., as a whole which would be born during this same ten year study). Details on familial structures and efficiency of genetic counselling are given, and this efficiency will be increased by the DNA study of the concerned families.  相似文献   
114.
Pregnancy terminated for a severe oligoamnios and renal dysplasia. Chromosomal, gonadal, internal genitalia sexes are female. There is a cloacal dysgenesis, with caudal appendice and hypoplastic external genitalia of male type. Single umbilical artery and congenital cardiac malformation (complete atrio ventricular communication) are associated. Embryopathologic explanation for this female pseudo-hermaphroditism is proposed.  相似文献   
115.

Introduction

Improving occupational performance is a key service of occupational therapists and client-centred approach to care is central to clinical practice. As such it is important to comprehensively evaluate the quality of psychometric properties reported across measures of occupational performance; in order to guide assessment and treatment planning.

Objective

To systematically review the literature on the psychometric properties of child-report measures of occupational performance for children ages 2–18 years.

Methods

A systematic search of the following six electronic databases was conducted: CINAHL; PsycINFO; EMBASE; PubMed; the Health and Psychosocial Instruments (HAPI) database; and Google Scholar. The quality of the studies was evaluated against the COSMIN taxonomy of measurement properties and the overall quality of psychometric properties was evaluated using pre-set psychometric criteria.

Results

Fifteen articles and one manual were reviewed to assess the psychometric properties of the six measures–the PEGS, MMD, CAPE, PAC, COSA, and OSA- which met the inclusion criteria. Most of the measures had conducted good quality studies to evaluate the psychometric properties of measures (PEGS, CAPE, PAC, OSA); however, the quality of the studies for two of these measures was relatively weak (MMD, COSA). When integrating the quality of the psychometric properties of the measures with the quality of the studies, the PAC stood out as having superior psychometric qualities.

Conclusions

The overall quality of the psychometric properties of most measures was limited. There is a need for continuing research into the psychometric properties of child-report measures of occupational performance, and to revise and improve the psychometric properties of existing measures.  相似文献   
116.
Abstract: PEA-15 (phosphoprotein enriched in astrocytes, Mr = 15,000) is an acidic serine-phosphorylated protein highly expressed in the CNS, where it can play a protective role against cytokine-induced apoptosis. PEA-15 is a major substrate for protein kinase C. Endothelins, which are known to exert pleiotropic effects on astrocytes, were used to analyze further the processes involved in PEA-15 phosphorylation. Endothelin-1 or endothelin-3 (0.1 µ M ) induced a robust phosphorylation of PEA-15 that was abolished by the removal of extracellular calcium, but only diminished by inhibitors of protein kinase C. Microsequencing of phosphopeptides generated by digestion of PEA-15 following endothelin-1 treatment identified two phosphorylated residues: Ser104, previously recognized as the protein kinase C site, and a novel phosphoserine, Ser116, located in a consensus motif for either protein kinase casein kinase II or calcium/calmodulin-dependent protein kinase II (CaMKII). Partly purified PEA-15 was a substrate in vitro for CaMKII, but not for casein kinase II. Two-dimensional phosphopeptide mapping demonstrated that the site phosphorylated in vitro by CaMKII was also phosphorylated in intact astrocytes in response to endothelin. CaMKII phosphorylated selectively Ser116 and had no effect on Ser104, but in vitro phosphorylation by CaMKII appeared to facilitate further phosphorylation by protein kinase C. Treatment of intact astrocytes with okadaic acid enhanced the phosphorylation of the CaMKII site. These results demonstrate that PEA-15 is phosphorylated in astrocytes by CaMKII (or a related kinase) and by protein kinase C in response to endothelin.  相似文献   
117.
Summary Internal motions play an important role in the biological function of proteins and NMR relaxation studies may characterize them over a wide range of frequencies. An experimental pulse scheme is proposed for the measurement of the 13CO-13C cross-relaxation rate. For sensitivity reasons, this measurement is performed in an indirect manner through several coherence transfer steps, which should thus be calibrated independently. Contributions of other relaxation pathways can be eliminated by the determination of the initial slope of the buildup curve. The cross-relaxation rates have been determined on a 15N-/13C-labelled 116-residue protein and the significant variations along the sequence have been interpreted as evidence of an increased amount of fast local motion.  相似文献   
118.
Distributional shifts in species ranges provide critical evidence of ecological responses to climate change. Assessments of climate-driven changes typically focus on broad-scale range shifts (e.g. poleward or upward), with ecological consequences at regional and local scales commonly overlooked. While these changes are informative for species presenting continuous geographic ranges, many species have discontinuous distributions—both natural (e.g. mountain or coastal species) or human-induced (e.g. species inhabiting fragmented landscapes)—where within-range changes can be significant. Here, we use an ecosystem engineer species (Sabellaria alveolata) with a naturally fragmented distribution as a case study to assess climate-driven changes in within-range occupancy across its entire global distribution. To this end, we applied landscape ecology metrics to outputs from species distribution modelling (SDM) in a novel unified framework. SDM predicted a 27.5% overall increase in the area of potentially suitable habitat under RCP 4.5 by 2050, which taken in isolation would have led to the classification of the species as a climate change winner. SDM further revealed that the latitudinal range is predicted to shrink because of decreased habitat suitability in the equatorward part of the range, not compensated by a poleward expansion. The use of landscape ecology metrics provided additional insights by identifying regions that are predicted to become increasingly fragmented in the future, potentially increasing extirpation risk by jeopardising metapopulation dynamics. This increased range fragmentation could have dramatic consequences for ecosystem structure and functioning. Importantly, the proposed framework—which brings together SDM and landscape metrics—can be widely used to study currently overlooked climate-driven changes in species internal range structure, without requiring detailed empirical knowledge of the modelled species. This approach represents an important advancement beyond predictive envelope approaches and could reveal itself as paramount for managers whose spatial scale of action usually ranges from local to regional.  相似文献   
119.
Relationship between ciliary rootlets and smooth endoplasmic reticulum   总被引:1,自引:0,他引:1  
Summary In ciliated cells of thymic cysts in Nude mice, ciliary rootlets are constantly and closely related to smooth endoplasmic reticulum and clear vesicles. This special association suggests that this structure does not play only an anchoring role but must be involved in the general metabolism of the cilium.This work was supported by Grant 10,013 from the Fonds de la Recherche Fondamentale Collective, Bruxelles, Belgium.Chargé de recherche au Fonds de la Recherche Scientifique.  相似文献   
120.
The first method for the qualitative and quantitative evaluation of extracellular and intracellular protease activities responsible for degradation of newly synthesized collagen is described. In a double incubation method, underhydroxylated collagen chains (protocollagen) serve as substrate for protease extract and then for the indicator enzyme, 4 prolyl hydroxylase. It was possible to characterize at least four types of protocollagen sites sensible to these proteases. The microsomal fraction of chick embryo liver contained a protease active on protocollagen and whose activity was similar to that of purified human synovial collagenase.  相似文献   
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