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51.
The trends of Road Traffic Accidents (RTA) in PNG illustrate a rapidly growing problem for developing countries. In this paper data of a time series for twenty years are analyzed to ascertain the trends in main indicators and injury rates. The relationship of injuries to road users and type of vehicle highlights the problems of passengers of utility vehicles and buses. An emerging problem of RTA due to use of light coaches for passenger transport is highlighted. The need for behavioral interventions and tighter regulations is argued.  相似文献   
52.
53.
The nucleotide sequence of the M2 gene segment of the mammalian reovirus prototype strain, type 3 Dearing, was determined from a cloned full-length cDNA copy of the viral double-stranded RNA segment. The gene comprises 2203 nucleotides and has a single long open reading frame that spans bases 30 through 2154 and encodes the 708 amino acid outer capsid protein mu 1. Aminoterminal sequence analysis of mu 1C, the proteolytically cleaved form of mu 1 that is found in purified reovirions, has identified the site of mu 1 to mu 1C cleavage between residues 42 and 43 in the mu 1 sequence. Aminoterminal sequence analysis of delta, the proteolytically cleaved product of mu 1C that is found in chymotrypsin-generated intermediate subviral particles, has indicated that the mu 1C to delta cleavage occurs near the carboxyterminus of mu 1C. Lastly, stoichiometric determinations using new sequence information have suggested that approximately equimolar amounts of mu 1C and the other major outer capsid component sigma 3 are present in virions. The data presented in this study should be useful for understanding the molecular basis of the functions of the mu 1 protein in reovirus entry into cells and in pathogenesis in the host animal.  相似文献   
54.
For many decades there was little consensus on the nature and type of pharmaceutical policies best suited for developing countries. In the aftermath of the Nairobi Conference on the Rational Use of Drugs and the formulation of criteria by expert groups convened by the World Health Organization a consensus has emerged on many aspects. Infrastructure development and the deployment of trained manpower are now perceived as two of the essential requisites for the implementation of national pharmaceutical policies. The article reviews selected problem areas in the pharmaceuticals sector and proposes strategies to overcome them.  相似文献   
55.
The piezoelectric coefficient (d(31)) and Young's modulus (E) were investigated as a function of degree of hydration for bovine cornea. The piezoelectric and mechanical responses observed were anisotropic, and d(31) decreased, whereas E increased with decreasing the degree of hydration. The anisotropic mechanical and electromechanical properties observed seem to be caused by oriented crystalline collagen fibrils. In addition, the loss of water molecules appears to decrease crystallinity (of the collagen) in the cornea. With dehydration of the cornea, a reduction in crystallinity and changes in hydrogen bonding were observed by wide-angle X-ray diffraction and Fourier transform infrared measurements. The decrease of piezoelectricity in cornea during dehydration is most likely caused by the increase in modulus and the loss of order to a nonpiezoelectric phase in the collagen.  相似文献   
56.
Women in low- and middle-income countries are known to make changes to their diets during pregnancy. We set out to explore the subject of traditional pregnancy diets with a view to finding out if migrant women follow these practices, and if such information might help explain differences in birth outcomes between migrant women and destination-country-born women. This review found that traditional pregnancy diets vary from region to region, that migrant women may follow some of these practices, and that there is a dearth of studies looking into the impact of pregnancy diets on birth outcomes.  相似文献   
57.
In neuroimage analysis, the automatic identification of symmetry plane has various applications. Despite the considerable amount of research, this remains an open problem. Most of the existing work based on image intensity is either sensitive to strong noise or not applicable to different imaging modalities. This paper presents a novel approach for identifying symmetry plane in three-dimensional brain magnetic resonance (MR) images based on the concepts of fractal dimension and lacunarity analysis which characterizes the complexity and homogeneity of an object. Experimental results, evaluation, and comparison with two other state-of-the-art techniques show the accuracy and the robustness of our method.  相似文献   
58.
Neurons of the deep cerebellar nuclei (DCN) play a critical role in defining the output of cerebellum in the course of encoding Purkinje cell inhibitory inputs. The earliest work performed with in vitro preparations established that DCN cells have the capacity to translate membrane hyperpolarizations into a rebound increase in firing frequency. The primary means of distinguishing between DCN neurons has been according to cell size and transmitter phenotype, but in some cases, differences in the firing properties of DCN cells maintained in vitro have been reported. In particular, it was shown that large diameter cells in the rat DCN exhibit two phenotypes of rebound discharge in vitro that may eventually help define their functional roles in cerebellar output. A transient burst and weak burst phenotype can be distinguished based on the frequency and pattern of rebound discharge immediately following a hyperpolarizing stimulus. Work to date indicates that the difference in excitability arises from at least the degree of activation of T-type Ca2+ current during the immediate phase of rebound firing and Ca2+-dependent K+ channels that underlie afterhyperpolarizations. Both phenotypes can be detected following stimulation of Purkinje cell inhibitory inputs under conditions that preserve resting membrane potential and natural ionic gradients. In this paper, we review the evidence supporting the existence of different rebound phenotypes in DCN cells and the ion channel expression patterns that underlie their generation.  相似文献   
59.
Ongoing care for chronic conditions is best provided by interprofessional teams. There are challenges in achieving this where teams cross organisational boundaries. This article explores the influence of organisational factors on collaboration between private and public sector primary and community health services involved in diabetes care. It involved a case study using qualitative methods. Forty-five participants from 20 organisations were purposively recruited. Data were collected through semi-structured interviews and from content analysis of documents. Thematic analysis was used employing a two-level coding system and cross case comparisons. The patterns of collaborative patient care were influenced by a combination of factors relating to the benefits and costs of collaboration and the influence of support mechanisms. Benefits lay in achieving common or complementary health or organisational goals. Costs were incurred in bridging differences in organisational size, structure, complexity and culture. Collaboration was easier between private sector organisations than between private and public sectors. Financial incentives were not sufficient to overcome organisational barriers. To achieve more coordinated primary and community health care structural changes are also needed to better align funding mechanisms, priorities and accountabilities of the different organisations.  相似文献   
60.
Thiazomycin is a novel thiazolyl peptide closely related to nocathiacin I. It was isolated from Amycolatopsis fastidiosa by chemical and biological screening. Thiazomycin showed highly potent bactericidal activity against Gram-positive pathogens (MIC range 0.002 approximately 0.064 microg/ml) and did not show cross-resistance to clinically relevant antibiotic classes such as beta-lactams, vancomycin, oxazolidinone and quinolones. It was highly efficacious against Staphylococcus aureus infection in mice exhibiting an ED(99) value of 0.15 mg/kg by subcutaneous administration. It inhibited bacterial growth by selective inhibition of protein synthesis and it was thought to interact with L11 protein and 23S rRNA of the 50S ribosome. Structurally, it possesses an oxazolidine ring in the amino-sugar residue that provides further opportunities for selective chemical modifications that are not feasible with other thiazolyl peptides. More importantly such a modification can potentially lead to semi-synthetic compounds that overcome problems that have hampered clinical development of this class of compounds. Despite its positive attributes, emergence of an unacceptable frequency of resistance poses significant challenges for further development of thiazomycin and this class of molecules for therapeutic use.  相似文献   
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