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51.
This article examines a clinicalsample of 66 Dominican and Puerto Ricansubjects who reported ataques de nerviosand also psychiatric disorder, and disentanglesthe phenomenological experiences of ataquede nervios, panic attacks, and panic disorder. In-depth cultural interviews assessed thesymptomatic phenomenology of ataqueepisodes from the local perspective as well asin terms of key panic features, such asrecurrence, rapid peaking of symptoms, and lackof provocation. Independent diagnosticassessments of panic attacks and disorder werealso used to establish the phenomenologicaloverlap between ataque and panic. Ourfindings indicate that 36 percent ofataques de nervios fulfill criteria for panicattacks and between 17 percent and 33 percentfor panic disorder, depending on the overlapmethod used. The main features distinguishingataques that fulfill panic criteria fromataques that do not include whether theepisodes were provoked by an upsetting event inthe person's life and the rapidity of crescendoof the actual attack. A key finding is thatataques often share individualphenomenological features with panic episodes,but that these features usually do not ``runtogether' during the ataque experience.This confirms previous findings thatataque is a more inclusive construct thanpanic disorder. The importance of thesefindings for the clinical diagnosis andtreatment of persons with ataques isdiscussed.  相似文献   
52.
Marine biodiversity and ecosystem services: an elusive link   总被引:13,自引:0,他引:13  
Efforts to test the hypothesised positive link between ecosystem services and functions and biodiversity are increasing in order to forecast the consequences of the present erosion of biodiversity on ecosystem functions and to provide an additional basis for the conservation of biodiversity. These efforts have been, however, modest in marine ecosystems. An examination of seagrass communities, which are simple assemblages with a limited membership of about 50 species worldwide and <12 species in any one community, provides, however, strong evidence for the existence of such positive link between species richness and ecosystem functions. Ecosystem functions are, however, dependent on the particular membership of the community, rather that its number, for the functions are species-specific properties. Yet evidence, is provided, that an increasing species richness should be, on average, linked to an increase in the functional repertoire present in the community, will lead to a more efficient use of resources and a greater capacity to ensure the sustainability of ecosystem functions under disturbance or ecosystem change. Closer examination indicates that the functional variability of mixed-species seagrass assemblages is correlated to the variability in species size, whereas species of similar size tend to show similar functional capacities and, therefore, a greater degree of functional redundancy. In addition, the demonstration of positive interactions in seagrass communities, which are also dependent on the presence of engineering species in the community that facilitate the growth of other species, provides increasing grounds to expect an enhanced functional performance of mixed communities over that expected from a simple additive contribution of the community members. Multispecific communities also hold, within the functional repertoire they contain, many unrealised functional potentials that may prove instrumental to ensure the sustainability of ecosystem functions in the presence of disturbance or a changing environment. The arguments offered, illustrated for the comparatively simple seagrass communities, provide strong reasons to expect a strong — if difficult to test experimentally — positive relationship between species diversity and the functions of marine ecosystems and, thereby, the services they yield to humanity.  相似文献   
53.
doi:10.1111/j.1741‐2358.2009.00320.x
Oral health and access to dental care: a qualitative investigation among older people in the community Objective: The aim of this study was to explore older persons’ beliefs and attitudes towards oral health and access to and use of dental care services. Background: As the proportion of dentate older people increases, the need and demand for dental services will rise (J Public Health Dent, 60, 2000, 276). Design: Focus groups and semi‐structured interviews were used for data collection. Setting and subjects: The study participants included 63 older people in Perth, WA. Results: Five major themes emerged from the interviews – the need for information and knowledge; accessibility of services; cost and affordability of oral care; fear and anxiety regarding dental visits and relationships with dentists. Attitudes and behaviours were slow to change in this group. Conclusion: This investigation provided important perspectives regarding oral health and dental access for older people residing in the community and demonstrated the importance of understanding this group when considering provision and use of services.  相似文献   
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55.
Aim In the current healthcare system primary care physicians (PCPs) have, in effect, become the primary psychiatric care physicians (PPCPs) for many of their patients. Being the PPCP in an already busy and stressful medical industry presents additional time management and treatment challenges to successfully manage patients' medical and psychiatric needs. The aim of the study was to ascertain PCPs' psychiatric assessment and treatment practices and to determine the extent to which PCPs have a need for using a structured psychiatric assessment tool.Method We sent 300 PCPs a survey to examine their psychiatric assessment and treatment practices. A one-page questionnaire was used to inquire about PCPs' psychiatric care practice habits including types of conditions treated, psychiatric medications prescribed, assessment methods used, interest in using a structured assessment tool and referral sources used. Sixty-eight usable surveys (23%) were returned.Results PCPs identify approximately one-third of their patients as mental health patients. They are treating a wide range of psychiatric conditions and prescribing a variety of psychiatric medications. The vast majority are using traditional clinical interviewing as their primary method of psychiatric assessment. However, the majority were willing to use a structured psychiatric assessment tool.Conclusion PCPs are serving a useful role in providing psychiatric treatment to many of their patients. Using a more structured psychiatric assessment method in practice could ultimately strengthen the assessment and treatment of psychiatric conditions in primary care settings.  相似文献   
56.
基于遥感与GIS技术,运用中国陆地生态系统服务价值当量表,结合当地粮食产量与粮食平均收购价格,分析了1960—2008年阿克苏河流域生态系统服务价值的变化,探讨了干旱区跨境河流流域生态系统服务变化对土地利用/覆被变化(LUCC)的响应.结果表明:研究期间,阿克苏河流域生态系统服务价值整体变化较小,总价值先减后增,沼泽、林地、草地面积的减少是总服务价值减少的主要原因,耕地和水域面积的增加补偿了总价值的部分损失,但损失略大于收益;各项生态功能的服务价值对总生态系统服务价值贡献大小的等级基本稳定,其中,土壤形成与保护和废物处理功能的贡献率最大;研究区生态系统服务价值大小及变化的空间差异较大,以流域下游的变化最频繁.敏感性分析表明,研究区内生态系统服务价值对服务价值指数缺乏弹性,研究结果具有稳健性.  相似文献   
57.
氮磷添加对红壤区城郊湿地松林凋落叶分解的影响   总被引:4,自引:0,他引:4  
城市化易导致城市森林氮(N)沉降和磷(P)富集,进而对凋落物分解过程产生影响。以位于南昌市郊的湿地松(Pinuse lliottii Engelm.)林为研究对象,采用尼龙网袋分解法,模拟N沉降(10g N·m-2·a-1,[N])、P积累(2.5g P·m-2·a-1,[P])和N沉降+P积累(10N·m-2·a-1+2.5g P·m-2·a-1,[N+P])对凋落叶分解速率与C、N、P含量及其化学计量比动态变化的影响。结果表明:与对照(CK)相比,[N]、[P]和[N+P]均促进凋落叶的前期(0~180d)分解速率,抑制中期(180~360d)、后期(360~540d)的分解速率;至540d时分解速率表现为[N]、[P]和CK无差异,但均高于[N+P](P0.05)。[N]提高分解过程中凋落叶N浓度,N含量表现为分解前期积累、后期释放;[P]提高分解过程中凋落叶P浓度,P含量持续积累;[N+P]提高N和P浓度,分解前期N、P含量积累,后期释放;而不同处理的C含量均表现为释放。凋落物基质C/N/P比与分解速率的相关性随分解阶段而表现各异。综合来看,城市化导致的N沉降和P富集叠加效应具有抑制城市森林凋落物分解过程的潜在性。  相似文献   
58.
城市湿地概念和功能及中国城市湿地保护   总被引:38,自引:0,他引:38  
随着城市化进程加快,城市湿地保护问题日益突出。城市湿地是存在于城市区域之内的湿地,其生态服务功能与乡野湿地有着明显不同。受人为活动干扰强烈,中国城市湿地存在面积缩小、功能退化、污染严重,特别是富营养化现象突出。而由于长期对城市湿地研究薄弱,对湿地功能与价值认识存在偏差,以及城市湿地保护较高的机会成本,使得中国城市湿地保护面临诸多困难。本文在分析中国城市湿地存在的问题基础上,提出中国城市湿地保护对策,并就当前中国城市湿地研究与保护问题进行探讨。  相似文献   
59.
The limited international resources for economic aid and conservation can only mitigate poverty and losses of biodiversity. Hence, developing nations must establish the capacity to resolve their problems. Additionally, policy-makers and donors need to obtain scientific input on issues such as global change and ecosystem services. We propose that for nations rich in biodiversity, ecosystem services derived from bioprospecting, or drug discovery, could contribute to economic development. In the case where unstudied samples are shipped abroad for research, the chances of obtaining royalties are infinitesimally small. Therefore developing nations will only realize benefits from bioprospecting through in-country research on their own biodiversity. Policy-makers and donors have failed to appreciate the value of this approach. In order to provide an example of the inherent links between conservation and sustainable economic development, we initiated a drug discovery effort in Panama that emphasizes local benefit. As much of the drug discovery process as possible is conducted in Panamanian laboratories, providing jobs dependent on intact biodiversity and enhancing local research and training. In short, research, plus the spin-offs from research, provide immediate and long-lasting benefits to Panama. The connection between conservation and development has been highlighted in publicity about the project in Panama’s urban media. This provides a constructive alternative to the perception the among the urban populace that economic development inevitably competes with conservation. In summary, our program uses biodiversity to promote human health as well as to support research capacity, economic development and conservation within Panama. The program provides an example of the widely recognized but little developed concept of bioprospecting research as an ecosystem service.  相似文献   
60.
A number of fundamental technical developments like the evolvement of oligonucleotide microarrays, new sequencing technologies and gene synthesis have considerably changed the character of genomic biological resource centres in recent years. While genomic biological resource centres traditionally served mainly as providers of sparsely characterized cDNA clones and clone sets, there is nowadays a clear tendency towards well-characterized, high-quality clones. In addition, major new service units like microarray services have developed, which are completely independent of clone collections, reflecting the co-evolution of data generation and technology development. The new technologies require an increasingly higher degree of specialization, data integration and quality standards. Altogether, these developments result in spin-offs of highly specialized biotech companies, some of which will take a prominent position in translational medicine.  相似文献   
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