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951.
Ten years after its introduction the Special Admissions to Psychiatric Hospitals Act (Bopz) still awaits full implementation in the field of psychogeriatric nursing home care. Ethnographic research into moral problems related to care giving in dementia patients in Dutch nursing homes yielded several reasons for this discrepancy between law and care practice. Firstly, practical effectuation of this law rests predominantly on the shoulders of nurses and nurse assistants who are mainly inspired by moral motives such as carefulness and providing safety and who are ill informed about the law and its prerequisites. Secondly, there is the problem of the loss of a common shared world of meaning, which in relational terms is typical for the process of dementia. As a result of this, crucial concepts of the Bopz loose their applicability as the disease progresses. Finally, there is an immanent tension between the anthropology of care and care giving and the anthropological presuppositions of the law, health law included, which on a fundamental level contributes to the resistance of the care practice to the legal procedures of the Bopz. These factors must be accounted for in new legislation or revision of the current law. In the mean time we urge the necessity to develop a moral code concerning how to deal with resistive behaviour and opposition to care of demented nursing home patients. 相似文献
952.
Jan Víteček Vojtěch Adam Jiří Petřek Jan Vacek René Kizek Ladislav Havel 《Plant Cell, Tissue and Organ Culture》2004,79(2):195-201
Growth is one of the basic properties of biological systems. The methods which are commonly used for the determination of growth are usually difficult and not very accurate. In the present work we decided to use esterase activity as a growth marker in tobacco suspension culture (BY-2 line) and in early somatic embryos of Norway spruce (clone 2/32) grown on a semi-solid medium. Esterase activity correlates well with the classical growth characteristics of BY-2 and spruce early somatic embryos. Determination of esterase activity is based on spectrophotometric and spectrofluorimetric detection of reaction products, which arise from the enzymatic hydrolysis of two substrates (p -nitrophenyl acetate and fluorescein diacetate) by esterase. The spectrophotometric method enabled us to detect approximately 104 BY-2 cells and 25 spruce embryos whereas the more sensitive spectrofluorimetric method allowed us to detect approximately 800 BY-2 cells and 5 early somatic embryos of Norway spruce. 相似文献
953.
954.
955.
Recognition of protein-DNA binding sites in genomic sequences is a crucial step for discovering biological functions of genomic sequences. Explosive growth in availability of sequence information has resulted in a demand for binding site detection methods with high specificity. The motivation of the work presented here is to address this demand by a systematic approach based on Maximum Likelihood Estimation. A general framework is developed in which a large class of binding site detection methods can be described in a uniform and consistent way. Protein-DNA binding is determined by binding energy, which is an approximately linear function within the space of sequence words. All matrix based binding word detectors can be regarded as different linear classifiers which attempt to estimate the linear separation implied by the binding energy function. The standard approaches of consensus sequences and profile matrices are described using this framework. A maximum likelihood approach for determining this linear separation leads to a novel matrix type, called the binding matrix. The binding matrix is the most specific matrix based classifier which is consistent with the input set of known binding words. It achieves significant improvements in specificity compared to other matrices. This is demonstrated using 95 sets of experimentally determined binding words provided by the TRANSFAC database. 相似文献
956.
957.
Raska I Koberna K Malínský J Fidlerová H Masata M 《Biology of the cell / under the auspices of the European Cell Biology Organization》2004,96(8):579-594
Ribosome biogenesis is a highly dynamic, steady-state nucleolar process that involves synthesis and maturation of rRNA, its transient interactions with non-ribosomal proteins and RNPs and assembly with ribosomal proteins. In the few years of the 21st century, an exciting progress in the molecular understanding of rRNA and ribosome biogenesis has taken place. In this review, we discuss the recent results on the regulation of rRNA synthesis in relation to the functional organization of the nucleolus, and put an emphasis on the situation encountered in mammalian somatic cells. 相似文献
958.
Schuurmans C Armant O Nieto M Stenman JM Britz O Klenin N Brown C Langevin LM Seibt J Tang H Cunningham JM Dyck R Walsh C Campbell K Polleux F Guillemot F 《The EMBO journal》2004,23(14):2892-2902
Neocortical projection neurons, which segregate into six cortical layers according to their birthdate, have diverse morphologies, axonal projections and molecular profiles, yet they share a common cortical regional identity and glutamatergic neurotransmission phenotype. Here we demonstrate that distinct genetic programs operate at different stages of corticogenesis to specify the properties shared by all neocortical neurons. Ngn1 and Ngn2 are required to specify the cortical (regional), glutamatergic (neurotransmitter) and laminar (temporal) characters of early-born (lower-layer) neurons, while simultaneously repressing an alternative subcortical, GABAergic neuronal phenotype. Subsequently, later-born (upper-layer) cortical neurons are specified in an Ngn-independent manner, requiring instead the synergistic activities of Pax6 and Tlx, which also control a binary choice between cortical/glutamatergic and subcortical/GABAergic fates. Our study thus reveals an unanticipated heterogeneity in the genetic mechanisms specifying the identity of neocortical projection neurons. 相似文献
959.
Hangeland JJ Doweyko AM Dejneka T Friends TJ Devasthale P Mellström K Sandberg J Grynfarb M Sack JS Einspahr H Färnegårdh M Husman B Ljunggren J Koehler K Sheppard C Malm J Ryono DE 《Bioorganic & medicinal chemistry letters》2004,14(13):3549-3553
A set of thyromimetics having improved selectivity for TR-beta1 were prepared by replacing the 3'-isopropyl group of 2 and 3 with substituents having increased steric bulk. From this limited SAR study, the most potent and selective compounds identified were derived from 2 and contained a 3'-phenyl moiety bearing small hydrophobic groups meta to the biphenyl link. X-ray crystal data of 15c complexed with TR-beta1 LBD shows methionine 442 to be displaced by the bulky R3' phenyl ethyl amide side chain. Movement of this amino acid side chain provides an expanded pocket for the bulky side chain while the ligand-receptor complex retains full agonist activity. 相似文献
960.
Much attention has focused on dendritic translational regulation of neuronal signaling and plasticity. For example, long-term memory in adult Drosophila requires Pumilio (Pum), an RNA binding protein that interacts with the RNA binding protein Nanos (Nos) to form a localized translation repression complex essential for anterior-posterior body patterning in early embryogenesis. Whether dendrite morphogenesis requires similar translational regulation is unknown. Here we report that nos and pum control the elaboration of high-order dendritic branches of class III and IV, but not class I and II, dendritic arborization (da) neurons. Analogous to their function in body patterning, nos and pum require each other to control dendrite morphogenesis, a process likely to involve translational regulation of nos itself. The control of dendrite morphogenesis by Nos/Pum, however, does not require hunchback, which is essential for body patterning. Interestingly, Nos protein is localized to RNA granules in the dendrites of da neurons, raising the possibility that the Nos/Pum translation repression complex operates in dendrites. This work serves as an entry point for future studies of dendritic translational control of dendrite morphogenesis. 相似文献