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31.
The unprecedented progress in bio-medical sciences and technology during the last few decades has resulted in great transformations in the concepts of health and disease, health systems and healthcare organisation and practices. Those changes have been accompanied by the emergence of a broad range of ethical dilemmas that confront health professionals more frequently. The classical Hippocratic ethical principles, though still retaining their relevance and validity, have become insufficiently adequate in an increasing range of problems and situations. Healthcare that has been practised for centuries on the basis of a direct doctor-patient relationship has been increasingly transformed into a more complex process integrating the health-team, the patient (healthcare seeker) and the community. Systematic review of the specialised literatures revealed that Healthcare Ethics education has become a basic requirement for any training programme for health professionals, and should cover the different stages of undergraduate, postgraduate and continuing education. Both theoretical foundations and practical skills are required for the appropriate ethical reasoning, ethical attitude and decision-making abilities. There is growing evidence that physicians' professional and moral development is not only determined by the formal curriculum of ethics; rather more, it is determined by the moral environment of the professional practice, the 'hidden curriculum' which deserves serious consideration by medical education.  相似文献   
32.
Cellular neurophysiological actions of nociceptin/orphanin FQ   总被引:2,自引:0,他引:2  
Moran TD  Abdulla FA  Smith PA 《Peptides》2000,21(7):969-976
Cellular actions of nociceptin/orphanin FQ (N/OFQ) resemble those of micro-, delta-, and kappa-opioids, i.e. activation of inwardly rectifying K(+) conductance, inhibition of high-voltage-activated Ca(2+) channel currents, and impediment of neurotransmitter release. Differences in ORL(1) and micro-receptor distribution lead to: 1) more widespread actions of N/OFQ on periaqueductal gray neurons than opioids and 2) differential effects of N/OFQ and opioids in the brainstem. Also, unlike opioids, N/OFQ inhibits T-type Ca(2+) channel current in sensory neurons. Opioids and N/OFQ may modulate glutamate responses in different ways, and certain actions of N/OFQ are potentiated following nerve injury whereas those of micro-opioids are attenuated. Agonists at ORL(1) receptors may therefore be of clinical interest in the management of neuropathic pain.  相似文献   
33.
An area-wide integrated tsetse eradication project was initiated in Zanzibar in 1994 by the International Atomic Energy Agency and the governments of Tanzania and Zanzibar, to eradicate Glossina austeni Newstead from Unguja Island (Zanzibar) using the sterile insect technique. Suppression of the tsetse population on Unguja was initiated in 1988 by applying residual pyrethroids as a pour-on formulation to livestock and by the deployment of insecticide impregnated screens in some of the forested areas. This was followed by sequential releases of gamma-sterilized male flies by light aircraft. The flies, packaged in carton release containers, were dispersed twice a week along specific flight lines separated by a distance of 1-2 km. More than 8.5 million sterile male flies were released by air from August 1994 to December 1997. A sterile to indigenous male ratio of >50:1 was obtained in mid-1995 and it increased to >100:1 by the end of 1995. As a consequence the proportion of sampled young females (1-2 ovulations), with an egg in utero in embryonic arrest or an uterus empty as a result of expulsion of a dead embryo, increased from <25% in the 1st quarter to >70% in the last quarter of 1995. In addition, the age structure of the female population became significantly distorted in favor of old flies (> or = 4 ovulations) by the end of 1995. The apparent density of the indigenous fly population declined rapidly in the last quarter of 1995, followed by a population crash in the beginning of 1996. The last trapped indigenous male and female flies were found in weeks 32 and 36, 1996, respectively. Time for 6 fly generations elapsed between the last catch of an indigenous fly and the end of the sterile male releases in December 1997.  相似文献   
34.
In cultures of rat tongue epithelial cells, cell proliferation following incubation with different doses of the potent tumor promoter TPA has been studied by using a stathmokinetic method counting colchicine arrested metaphases. It was demonstrated that 24 h incubation with concentrations higher than 5 ng TPA/mL medium caused inhibition, whereas below 5 ng TPA/mL medium caused stimulation of the mitotic activity reaching a maximum around 30 h from the start of the incubation period. Based on the evidence of the anticarcinogenic effect of selenium in several animal models, experiments have been performed elucidating the influence of an atoxic dose (1/1.000.000M) of selenite on the observed TPA-induced cell proliferation. Our results indicate that addition to the culture medium of an atoxic dose of selenite, not affecting the mitotic activity of control cultures, inhibits the TPA-induced stimulation of cell proliferation.  相似文献   
35.
根据对新疆博格达山岩面生地衣群落20个样点(20m×20m)调查的数据,以各地衣种的盖度为指标结合双向指示种分析方法(TWINSPAN)和除趋势对应分析法(DCA)对博格达山岩面生地衣群落进行数量分类并分析了群落结构特征及其多样性和相似性。采用典范对应分析法(CCA)对各群落的物种分布格局与环境因子的关系进行研究。结果表明,TWINSPAN分析和DCA排序将分布在博格达山的37种岩面生地衣分为以下5个群丛。群丛1:斑纹网衣(Lecidea tessellate Florke)+粉芽盾衣(Peltula euploca(Ach.)Poelt)+杜瑞氏黄梅(Xanthoparmelia durietzii Hale)群丛,有25个种,总覆盖度为30.145%,多样性为4.025;群丛2:袋衣(Hypogymnia physodes(L.)Nyl.)+白边平茶渍(Aspicilia sublaqueata(H.Magn.)J.C.Wei)+砖孢胶衣(Collema subconveniens Nyl.)群丛,有17个种,地衣总盖度为15.885%,多样性为3.196;群丛3:聚茶渍(Lecanora accumulate H.Magn.)+丽石黄衣(Xanthoria elegans(Link)Th.Fr.)+亚洲平茶渍(Aspicilia asiatica(H.Magn.)Yoshim.)群丛,有30个种,地衣总盖度为37.87%,多样性为4.357;群丛4:中华石果衣(Endocarpon sinense H.Magn.)+伴藓大孢蜈蚣衣(Physconia muscigena(Ach.)Poelt.)+垫脐鳞衣(Rhizoplaca melanophthalma(DC.)LeuckertPoelt)群丛,有24个种,地衣总盖度为30.458%,多样性为3.912;群丛5:石胶衣(Collema flaccidum(Ach.)Ach.)+短绒皮果衣(Dermatocarpon vellereum Zschacke)+绿黑地图衣(Rhizocarpon viridiatrum(Wulfen)Korber.)群丛,有18个种,地衣总盖度为19.331%,多样性为3.515。CCA排序结果反映,该地区岩面生地衣的分布与海拔高度、光照强度、岩石pH和人为干扰有关,其中影响最大的因素是海拔高度,其次为光照强度和干扰。坡向和岩石大小对地衣种类分布的影响不显著。  相似文献   
36.
Aquaculture practices from sub-Saharan Africa are characterised by low production, owing to improper technology. Production can be increased through integrating fish farming with other existing on-farm activities, particularly livestock husbandry. We assessed the role of fish-poultry integration on all male Nile tilapia, Oreochromis niloticus growth performance, yields and economic benefits among smallholder farmers in sub-Saharan Africa, Tanzania. The study also compared phytoplankton species composition, abundance and biomass between the fish-poultry integration and non-integrated system. After 180 days of the experiment, all male O. niloticus cultured under fish-poultry integration exhibited significantly higher growth rates than those in the non-integrated system (p < 0.05). Gross fish yield (GFY), net fish yield (NFY) and net annual yields (NAY) obtained from fish-poultry integration were significantly higher than those from non-integrated system (p < 0.05). Partial enterprise budget analysis revealed that fish-poultry integration was more profitable than the non-integrated system. Moreover, fish-poultry integrated system produced significantly higher phytoplankton abundance and biomass than those from the non-integrated system. Results demonstrate that rural smallholder farmers can achieve higher growth rate, farm net yields and income by integrating all male O. niloticus with other on-farm activities than practising a stand-alone fish culture system.  相似文献   
37.
A significant portion of organic phosphorus comprises of phytates which are not available to wheat for uptake. Hence for enabling wheat to utilize organic phosphorus in form of phytate, transgenic wheat expressing phytase from Aspergillus japonicus under barley root-specific promoter was developed. Transgenic events were initially screened via selection media containing BASTA, followed by PCR and BASTA leaf paint assay after hardening. Out of 138 successfully regenerated To events, only 12 had complete constructs and thus further analyzed. Positive T1 transgenic plants, grown in sand, exhibited 0.08–1.77, 0.02–0.67 and 0.44–2.14 fold increase in phytase activity in root extracts, intact roots and external root solution, respectively, after 4 weeks of phosphorus stress. Based on these results, T2 generation of four best transgenic events was further analyzed which showed up to 1.32, 56.89, and 15.40 fold increase in phytase activity in root extracts, intact roots and external root solution, respectively, while in case of real-time PCR, maximum fold increase of 19.8 in gene expression was observed. Transgenic lines showed 0.01–1.18 fold increase in phosphorus efficiency along with higher phosphorus content when supplied phytate or inorganic phosphorus than control plants. Thus, this transgenic wheat may aid in reducing fertilizer utilization and enhancing wheat yield.  相似文献   
38.
39.
ObjectiveMaize is an important crop for fodder, food and feed industry. The present study explores the plant-microbe interactions as alternative eco-friendly sustainable strategies to enhance the crop yield.MethodologyBacterial diversity was studied in the rhizosphere of maize by culture-dependent and culture-independent techniques by soil sampling, extraction of DNA, amplification of gene of interest, cloning of desired fragment and library construction.ResultsCulturable bacteria were identified as Achromobacter, Agrobacterium, Azospirillum, Bacillus, Brevibacillus, Bosea, Enterobacter, Microbacterium, Pseudomonas, Rhodococcus, Stenotrophomonas and Xanthomonas genera. For culture-independent approach, clone library of 16S ribosomal RNA gene was assembled and 100 randomly selected clones were sequenced. Majority of the sequences were related to Firmicutes (17%), Acidobacteria (16%), Actinobacteria (17%), Alpha-Proteobacteria (7%), Delta-proteobacteria (4.2%) and Gemmatimonadetes (4.2%) However, some of the sequences (30%) were novel that showed no homologies to phyla of cultured bacteria in the database. Diversity of diazotrophic bacteria in the rhizosphere investigated by analysis of PCR-amplified nifH gene sequence that revealed abundance of sequences belonging to genera Azoarcus (25%), Aeromonas (10%), Pseudomonas (10%). The diazotrophic genera Azotobacter, Agrobacterium and Zoogloea related nifH sequences were also detected but no sequence related to Azospirillum was found showing biasness of the growth medium rather than relative abundance of diazotrophs in the rhizosphere.ConclusionThe study provides a foundation for future research on focussed isolation of the Azoarcus and other diazotrophs found in higher abundance in the rhizosphere.  相似文献   
40.
IntroductionSmall fiber neuropathy might be a part of typical mixed small and large fiber neuropathy, or a distinct entity, affecting exclusively small nerve fibers.ObjectivesExplore the utility of small nerve fiber testing in patients with clinical presentation suggesting small fiber neuropathy, with and without evidence for concomitant large fiber neuropathy.MethodsPatients attending the neuromuscular clinic from 2012 to 2015 with a clinical presentation suggesting small nerve fiber impairment, who had Laser Doppler flare imaging (LDIFlare) and quantitative thermal testing (QTT) were evaluated for this study. Patients with clinical or electrophysiological evidence for concomitant large fiber neuropathy were not excluded.ResultsThe sensitivities of LDIFlare, cooling and heat threshold testing were 64%, 36%, and 0% respectively for clinically highly suggestive small fiber neuropathy, 64%, 56%, and 19% respectively for mixed fiber neuropathy, and 86%, 79%, and 29% respectively for diabetic mixed fiber neuropathy.DiscussionLDIFlare and cooling thresholds testing are non-invasive small nerve fiber testing modalities, with moderate performance in patients with small and mixed fiber neuropathy, and excellent performance in diabetic mixed fiber neuropathy.  相似文献   
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