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1.
Eleven morphometric and one meristic character in 15 parthenogeneticArtemia populations have been studied by using discriminant andcluster analysis as well as scanning electron microscopy.Discriminant analysis revealed five main groups of morphologicalpatterns: (i) the coastal Chinese populations together with apopulation from Kazakhstan, (ii) the inland Chinese salt lakepopulations, (iii) the Greek populations, (iv) one African populationfrom Namibia and (v) a Chinese population from Xuyu (Jiangsuprovince). Cluster analysis was not always in agreement withdiscriminant analysis and these results are discussed.  相似文献   
2.
Detection of antibodies to DNA: a technical assessment.   总被引:6,自引:0,他引:6  
Antibodies to DNA can be found in the circulation of the majority of patients with Systemic Lupus Erythematosus (SLE). They are quite specific for this disease, which makes their detection an important diagnostic aid to the clinician. Fluctuations in the level of anti-dsDNA in an individual patient generally parallel the clinical state of that patient. Furthermore, the presence of anti-dsDNA may precede the diagnosis of SLE by more than a year. Four methods relevant for the measurement of anti-dsDNA antibodies are discussed in this paper: the ELISA, the indirect immunofluorescence test on Crithidia luciliae, the PEG assay, and the Farr assay. Each of these methods detects a part of the spectrum of anti-dsDNA antibodies present in the circulation of an individual patient. The ELISA is the most sensitive method, whereas the Farr assay is the most specific for SLE. However, with the latter method only antibodies of a relative high avidity for DNA are detected. Mild forms of SLE, where patients only have anti-dsDNA of a low avidity in their circulation, may easily be missed by this technique. Clinically, high avidity anti-dsDNA is related with the more frequent occurrence of nephritis, whereas low avidity anti-dsDNA antibodies are more often found in patients with central nervous system involvement.  相似文献   
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To examine the potential use of synthesis gas as a carbon and energy source in fermentation processes, Rhodospirillum rubrum was cultured on synthesis gas generated from discarded seed corn. The growth rates, growth and poly-beta-hydroxyalkanoates (PHA) yields, and CO oxidation/H(2) evolution rates were evaluated in comparison to the rates observed with an artificial synthesis gas mixture. Depending on the gas conditioning system used, synthesis gas either stimulated or inhibited CO-oxidation rates compared to the observations with the artificial synthesis gas mixture. Inhibitory and stimulatory compounds in synthesis gas could be removed by the addition of activated charcoal, char-tar, or char-ash filters (char, tar, and ash are gasification residues). In batch fermentations, approximately 1.4 mol CO was oxidized per day per g cell protein with the production of 0.75 mol H(2) and 340 mg PHA per day per g cell protein. The PHA produced from R. rubrum grown on synthesis gas was composed of 86% beta-hydroxybutyrate and 14% beta-hydroxyvalerate. Mass transfer of CO into the liquid phase was determined as the rate-limiting step in the fermentation.  相似文献   
5.
Objective: To investigate whether for patients with incurable cancer comprehensive home care programmes are more effective than standard care in maintaining the patients’ quality of life and reducing their “readmission time” (percentage of days spent in hospital from start of care till death). Design: Systematic review. Methods: A computer aided search was conducted using the databases of Medline, Embase, CancerLit, and PsychLit. The search for studies and the assessment of the methodological quality of the relevant studies were performed by two investigators, blinded from each other. Prospective, controlled studies investigating the effects of a home care intervention programme on patients’ quality of life or on readmission time were included in the analyses. Results: Only 9 prospective controlled studies were found; eight were performed in the United States and 1 in the United Kingdom. Their methodological quality was judged to be moderate (median rating 62 on a 100 point scale). None of the studies showed a negative influence of home care interventions on quality of life. A significantly positive influence on the outcome measures was seen in 2 out of the 5 studies measuring patients’ satisfaction with care, in 3/7 studies measuring physical dimensions of quality of life, in 1/6 studies measuring psychosocial dimensions, and in 2/5 studies measuring readmission time. The incorporation of team members’ visits to patients at home or regular multidisciplinary team meetings into the intervention programme seemed to be related to positive results. Conclusions: The effectiveness of comprehensive home care programmes remains unclear. Given the enormity of the problems faced by society in caring for patients with terminal cancer, further research is urgently needed.

Key messages

  • Only nine controlled prospective studies have compared the effects of home care intervention programmes for patients with terminal cancer with those of standard care, in relation to patients’ quality of life and time spent in hospital between start of care and death
  • The methodological quality of these studies seemed to be moderate
  • Home care programmes did not have a negative influence on quality of life or time spent in hospital; some studies observed positive effects on these outcome measures
  • Enabling team members to visit patients at home and holding regular multidisciplinary team meetings seem important elements for obtaining favourable results
  • The general belief that home care programmes are effective for patients with terminal cancer is not supported scientifically
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7.
The tify family previously known as ZIM   总被引:6,自引:0,他引:6  
The ZIM domain was originally identified in the ZIM protein (BAA97679; Zinc-finger protein expressed in Inflorescence Meristem). Since then it has been found in other proteins and the corresponding genes have been grouped into a plant-specific family. However, the family lacks consistency in its classification among different databases. Here, we try to clarify this incongruity by presenting an overview of the Arabidopsis proteins having this domain. The presented genome-wide survey can be seen as a start point to reveal the unknown function of these proteins. Furthermore, because of the confusing ZIM nomenclature being used at present, we propose to rename the domain and family as tify, after the most conserved amino acid motif characterizing the members of this family.  相似文献   
8.
Although osteoporosis and its related fractures are common in patients with COPD, patients at high risk of fracture are poorly identified, and consequently, undertreated. Since there are no fracture prevention guidelines available that focus on COPD patients, we developed a clinical approach to improve the identification and treatment of COPD patients at high risk of fracture. We organised a round-table discussion with 8 clinical experts in the field of COPD and fracture prevention in the Netherlands in December 2013. The clinical experts presented a review of the literature on COPD, osteoporosis and fracture prevention. Based on the Dutch fracture prevention guideline, they developed a 5-step clinical approach for fracture prevention in COPD. Thereby, they took into account both classical risk factors for fracture (low body mass index, older age, personal and family history of fracture, immobility, smoking, alcohol intake, use of glucocorticoids and increased fall risk) and COPD-specific risk factors for fracture (severe airflow obstruction, pulmonary exacerbations and oxygen therapy). Severe COPD (defined as postbronchodilator FEV1 < 50% predicted) was added as COPD-specific risk factor to the list of classical risk factors for fracture. The 5-step clinical approach starts with case finding using clinical risk factors, followed by risk evaluation (dual energy X-ray absorptiometry and imaging of the spine), differential diagnosis, treatment and follow-up. This systematic clinical approach, which is evidence-based and easy-to-use in daily practice by pulmonologists, should contribute to optimise fracture prevention in COPD patients at high risk of fracture.  相似文献   
9.
To enhance the efficacy of fenretinide (4HPR)-induced reactive oxygen species (ROS) in neuroblastoma, 4HPR was combined with buthionine sulfoximine (BSO), an inhibitor of glutathione (GSH) synthesis, in neuroblastoma cell lines and spheroids, the latter being a three-dimensional tumor model. 4HPR exposure (2.5-10 μM, 24 h) resulted in ROS induction (114-633%) and increased GSH levels (68-120%). A GSH depletion of 80% of basal levels was observed in the presence of BSO (25-100 μM, 24 h). The 4HPR-BSO combination resulted in slightly increased ROS levels (1.1- to 1.3-fold) accompanied by an increase in cytotoxicity (110-150%) compared to 4HPR treatment alone. A correlation was observed between the ROS-inducing capacity of each cell line and the increase in cytotoxicity induced by 4HPR-BSO compared to 4HPR. No significant correlation between baseline antioxidant levels and sensitivity to 4HPR or BSO was observed. In spheroids, 4HPR-BSO induced a strong synergistic growth retardation and induction of apoptosis. Our data show that BSO increased the cytotoxic effects of 4HPR in neuroblastoma monolayers and spheroids in ROS-producing cell lines. This indicates that the 4HPR-BSO combination might be a promising new strategy in the treatment of neuroblastoma.  相似文献   
10.
Epidermally derived tendon cells attach the exoskeleton (cuticle) of the Branchiopod crustacean, Artemia franciscana, to underlying muscle in the hindgut, while the structurally similar transalar tendon (epithelial) cells, which also arise from the epidermis and are polarized, connect dorsal and ventral exopodite surfaces. To establish these latter attachments the transalar tendon cells interact with cuticles on opposite sides of the exopodite by way of their apical surfaces and with one another via basal regions, or the cuticle attachments may be mediated through linkages with phagocytic storage cells found in the hemolymph. In some cases, phyllopod tendon cells attach directly to muscle cells. Tendon cells in the hindgut of Artemia possess microtubule bundles, as do the transalar cells, and they extend from the basal myotendinal junction to the apical domain located near the cuticle. The bundled microtubules intermingle with thin filaments reminiscent of microfilaments, but intermediate filament-like structures are absent. Microtubule bundles converging at apical cell surfaces contact structures termed apical invaginations, composed of cytoplasmic membrane infoldings associated with electron-dense material. Intracuticular rods protrude from apical invaginations, either into the cuticle during intermolt or the molting fluid in premolt. Confocal microscopy of immunofluorescently stained samples revealed tyrosinated, detyrosinated, and acetylated tubulins, the first time posttranslationally modified isoforms of this protein have been demonstrated in crustacean tendon cells. Microfilaments, as shown by staining with phalloidin, coincided spatially with microtubule bundles. Artemia tendon cells clearly represent an interesting system for study of cytoskeleton organization within the context of cytoplasmic polarity and the results in this article indicate functional cooperation of microtubules and microfilaments. These cytoskeletal elements, either acting independently or in concert, may transmit tension from muscle to cuticle in the hindgut and resist compression when connecting exopodite cuticular surfaces.  相似文献   
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