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991.
A 68-year-old man presented with hemiparesis, lymphocytosis, and cerebral lesions on MRI. Flow cytometry of blood, bone marrow and cerebrospinal fluid showed B-CLL lymphocytes with bright CD20 expression, slg, and absence of CD23 antigen. Fluorescencein situ hybridisation showed trisomy 12 in 50% of analysed peripheral mononuclear cells. The patient died 6 months after the diagnosis. Rapidly progressive and fatal course of the disease was consistent with known bad prognostic significance of CD20 bright expression and trisomy 12.  相似文献   
992.
Sugar cane bagasse was water- or alkali-treated at three liquid/solid (L/S) ratios and its digestibility was measured as microbial protein production of Chaetomium cellulolyticum grown on solid-state fermentation columns. The treatments significantly enhanced fungus growth compared to non-treated bagasse, which was used as a control, although the composition of bagasse did not change greatly. Alkali-treated bagasse reached an average protein content of about 7.6% and the lower the L/S ratio, the higher the protein content. L/S ratio did not have an effect in water-treated bagasse. Protein content of water-treated bagasse was also high, approximately 80% of that one of alkali-treated bagasse. Both treatments look promising to enhance sugar cane bagasse potential as an animal feed.Currently at Universidad Francisco de Miranda. Coro, Venezuela.Currently at Ciclo Básico, Facultad de Ingeniería, Universidad del Zulia. Maracaibo, Venezuela.  相似文献   
993.
The dynamic microtubule cytoskeleton plays fundamental roles in the growth and development of plants including regulation of their responses to environmental stress. Plants exposed to hyper-osmotic stress commonly acclimate, acquiring tolerance to variable stress levels. The underlying cellular mechanisms are largely unknown. Here, we show, for the first time, by in vivo imaging approach that linear patterns of phospholipase Dδ match the localization of microtubules in various biological systems, validating previously predicted connection between phospholipase Dδ and microtubules. Both the microtubule and linear phospholipase Dδ structures were disintegrated in a few minutes after treatment with oryzalin or salt. Moreover, by using immunofluorescence confocal microscopy of the cells in the root elongation zone of Arabidopsis, we have shown that the cortical microtubules rapidly depolymerized within 30 min of treatment with 150 or 200 mM NaCl. Within 5 h of treatment, the density of microtubule arrays was partially restored. A T-DNA insertional mutant lacking phospholipase Dδ showed poor recovery of microtubule arrays following salt exposition. The restoration of microtubules was significantly retarded as well as the rate of root growth, but roots of overexpressor GFP-PLDδ prepared in our lab, have grown slightly better compared to wild-type plants. Our results indicate that phospholipase Dδ is involved in salt stress tolerance, possibly by direct anchoring and stabilization of de novo emerging microtubules to the plasma membrane, providing novel insight into common molecular mechanism during various stress events.  相似文献   
994.
995.
We investigated the biological activity of a series of substituted chromeno[3,2-c]pyridines, including compounds previously synthesized by our group and novel compounds whose syntheses are reported here. Tandem transformation of their tetrahydropyridine ring under the action of activated alkynes yielding 2-vinylsubstituted chromones was used to prepare nitrogen-containing derivatives of a biologically active chromone system. The inhibitory activity of these chromone derivatives against acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and carboxylesterase (CaE) was investigated using the methods of enzyme kinetics and molecular docking. Antioxidant (antiradical) activity of the compounds was assessed in the ABTS assay. The results demonstrated that a subset of the studied chromone derivatives selectively inhibit BChE but do not exhibit antiradical activity. In addition, the results of molecular docking effectively explained the observed features in the efficacy, selectivity, and mechanism of BChE inhibition by the chromone derivatives.  相似文献   
996.

Objective

The aim of this study is to identify the risks factors for mortality and functional recovery in elderly patients admitted to hospital with a hip fracture.

Materials and methods

Longitudinal prospective study in patients 80 years old or more and patients between 75 and 79 in residential home care with a hip fracture and with a past medical history of dementia or followed-up by the Geriatric Unit. A total of 359 patients were included, and the demographic data, previous functional status, comorbidity, type of fracture, and dementia were recorded. The data collected during admission included time to surgery, delirium, functional recovery, length of stay, placement at discharge, and mortality. Patients were followed-up for one year and details were collected on placement at the end of follow-up, functional recovery, medical complications, and mortality.

Results

The baseline characteristics of the patients with a strong association with mortality after a hip fracture were old age (> 92 years), medical complications delaying surgery (HR 2.17; 95% CI; 1.27-3.73), diagnosis of dementia (HR 1.78; 95% CI; 1.15-2.75), or heart failure (HR 1.75; 95% CI; 1.12-2.75). The fitted multivariable regression models showed that functional impairment before the hip fracture or lack of functional recovery are associated with higher mortality, and patients with increased age, delirium, dementia, and previous functional impairment showed worse functional recovery.

Conclusion

In the elderly patients with a hip fracture, increased age, comorbidity and previous functional status is associated with mortality. Functional recovery prognosis will depend on age, previous functional status, past medical history of dementia, and the presence of delirium during admission.  相似文献   
997.
To examine the effect of soil type on carrot weevil, Listronotus oregonensis, (Coleoptera: Curculionidae), movement behavior we conducted a series of laboratory arena experiments with the use of three soil types: mineral soil, organic soil and pure sand. We found that soil type influences carrot weevil burrowing activity and movement and showed that carrot weevil is more inclined to burrow into mineral and organic soils than pure sand and displays avoidance of the latter. While barriers constructed out of pure sand induced burrowing activity only in 3% of tested weevils, mineral and organic soil barriers initiated burrowing in 67% and 38% of tested weevils respectively. All weevils crossed pure sand barriers, whereas 18% (mineral soil) and 6% (organic soil) were arrested and engaged in burrowing activities. In addition, carrot weevil movement behavior at the border of two substrates, revealed high edge permeability of mineral and organic soils and reduced permeability of pure sand edges. Over 70% of weevils released on organic soil ended up not crossing the border with another substrate. All tested weevils released on pure sand crossed the border within less than 1 min. Replication of the experiments with autoclaved soil suggested that the observed differences in carrot weevil movement behavior were largely due to soil texture and not strongly influenced by micro-organisms or odor.  相似文献   
998.
Two new photoactive compounds (1 and 2) derived from the 9-amidoacridine chromophore have been synthesized and fully characterized. Their abilities to produce singlet oxygen upon irradiation have been compared. The synthesized compounds show very different self-aggregating properties since only 1 present a strong tendency to aggregate in water. Biological assays were conducted with two cell types: hepatoma cells (Hep3B) and human umbilical vein endothelial cells (HUVEC). Photodynamic therapy (PDT) studies carried out with Hep3B cells showed that non-aggregating compound 2 showed photoxicity, ascribed to the production of singlet oxygen, being aggregating compound 1 photochemically inactive. On the other hand suspensions of 1, characterized as nano-sized aggregates, have notable antiproliferative activity towards this cell line in the dark.  相似文献   
999.
The novel isosteric ribavirin analogues were synthesized by two different ways. Some of them showed significant antiviral action against hepatitis C virus (HCV), herpes simplex (HCV-1) and influenza A virus comparable to that of ribavirin itself. The data obtained confirm the proposed theory of the ribavirin possible antiviral activity mechanism related with bioisosterism.  相似文献   
1000.

Purpose

This article aims to analyze the role that third-party product sustainability certifications play in supply chain sustainability governance and hence the impact that they may have on facilitating corporate life cycle management (LCM). Particular emphasis is given to exploring the extent to which such schemes allow firms to outsource the work of communication, motivation, enablement, and control of sustainability-related information and performance upstream in the supply chain.

Methods

The research design is based on a comparative case study methodology. The corporate practices of sourcing the sustainability certified products in the food retailing and textile sectors are compared, to explain when third-party product sustainability certification reduces the corporate need to engage in collaborative relationships with suppliers, thereby reducing efforts associated with implementation of corporate life cycle management.

Results and discussion

In our study, we found evidence that affirms the role of third-party product sustainability certification in reducing corporate necessity to actively engage with coordination of sustainability issues upstream in the supply chain. However, we also identified a range of factors—the intention of the buying company, the supply chain context, and the design of the certification scheme—that influence the extent, to which third-party product sustainability certification replaces the corporate need for additional work to facilitate supplier compliance. Some of these factors, e.g., the design of the certification scheme, are new and have been underexplored in the supply chain management and value chain governance literature yet.

Conclusions

Our findings suggest that corporate LCM practitioners should consider third-party sustainability certification as an instrument for the transfer of significant life cycle information along the supply chain and as a tool to facilitate corporate life cycle management. The extent to which third-party product sustainability certification would be able to facilitate corporate life cycle management depends not only on whether certification requirements are based on the LCA studies but also on the market scope of the certification schemes, the scope of the certification requirements, and the architecture of the certification management services. If these parameters are aligned with corporate ambitions and allow buyers to fully outsource the work associated with communication, motivation, enablement, and control of sustainability-related information and supplier performance, the life cycle management can be exercised by companies by simply choosing to procure sustainability certified products.
  相似文献   
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