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1.
Inborn errors of metabolism (IEM) are a relevant cause of morbidity and death among children, and neonates in particular. However, little is known about the prevalence of these disorders in Brazilian newborns. Our laboratory of IEM (LABEIM) at the Department of Biochemistry, Institute of Chemistry, Federal University of Rio de Janeiro (UFRJ), has been working on the diagnosis of IEM since 1988. Out of 3,300 patients (90% children), screened and evaluated from 1989 to 2,000 because of a high clinical suspicion of having an IEM, 323 (9.8%) were neonates. Patients came from different regions of the state of Rio de Janeiro, in which lives approximately 8.5% of the total Brazilian population. Chemical tests, various chromatographic techniques and enzyme assays were performed in urine, plasma and in some cases, cerebrospinal fluid (CSF). This study describes our laboratory and the experience with the 323 investigated neonates, among which 28 cases (8.7%) of IEM were identified and 18 (5.6%), strongly suspected. All these cases were related mainly to the metabolism of amino acids, organic acids, lysosomal enzymes and carbohydrates. Furthermore, data on population, community and health services are presented.  相似文献   

2.
Aguiar MJ 《Community genetics》2004,7(2-3):117-120
The state of Minas Gerais in Brazil has a surface of 586,528 km(2), and 18 million inhabitants. Infant mortality rate is 20/1,000, and congenital anomalies are its second cause. There are 11 medical schools where basic genetics, but not clinical genetics, is taught. Genetic services in the state include: newborn screening for hypothyroidism, phenylketonuria, sickle cell disease and cystic fibrosis; clinical-genetic diagnostic evaluation and counseling; prenatal diagnosis, fetal medicine and paternity testing. Medical genetic services and research are underdeveloped because of limitations such as lack of health policies in genetics, small number of trained specialists, little knowledge about genetics among health professionals and low reimbursement rates.  相似文献   

3.
The World Health Organization sponsored a Consultation on Community Genetic Services and a Regional Network of Medical Genetics in Latin America in Porto Alegre, Brazil, on June 19, 2003. The main recommendations of the meeting included: (a) the call for government funding of services, research and education in medical genetics; (b) the conduct of epidemiological research on the prevalence and types of birth defects, genetic disorders and genetic predispositions to common diseases; (c) the education of health professionals in genetics; (d) the education of genetic professionals in community health and public health genetics; (e) the fostering of interactions between clinical geneticists, public health personnel, primary health care workers and community organizations, and (f) a better planning of regionalized services to avoid duplication and inefficiency.  相似文献   

4.
Objective: To describe and compare the information obstetricians and geneticists in five European countries report they would give following the prenatal diagnosis of Klinefelter syndrome. Methods: 388 obstetricians and 269 geneticists from Germany, the Netherlands, Portugal, Spain and the UK completed a brief questionnaire assessing two variables: the information they reported providing to parents following the prenatal diagnosis of Klinefelter syndrome (categorized as positive or negative); and their perceptions of the quality of life with the condition. Results: Geneticists were more likely than obstetricians to report providing more positive than negative information about Klinefelter syndrome than equal amounts of positive and negative information or more negative than positive information about the condition (excess positive information). Regardless of specialty, the information that health professionals reported providing was predicted by their perceptions of the quality of life with the condition, and the country from which they came. Those perceiving quality of life as greater were more likely to provide an excess positive information, as were health professionals from Germany and the UK. Conclusions: These results suggest that the information parents across Europe receive after the prenatal diagnosis of Klinefelter syndrome varies according to the specialty and country of the health professionals consulted, and their perceptions of quality of life with the condition. This variation seems to reflect personal, cultural and professional differences between health professionals. Copyright 2002 S. Karger AG, Basel  相似文献   

5.
The emerging possibilities of applying new diagnostic technologies for genetic diagnosis and screening point to the need for a discipline of community genetics. Genetic population screening for haemoglobin disorders (thalassaemias and sickle cell disorders) has been practised on a large scale for over 20 years, and basic concepts and methods of community genetics have been developed within this framework, under the auspices of the WHO. Genetic population screening is a public health activity. It involves many disciplines, and planning depends on reliable and regularly updated information. Basic methods for describing genetic epidemiology in terms of service needs, and for regular service audit have been developed, and IT-based approaches for making simple, accurate and diagnosis-specific information accessible to the public and health professionals are being explored.  相似文献   

6.
There are many impediments to the progress of clinical and medical genetics in developing countries. Higher priorities concerning basic health care usually take precedence over genetic diseases and birth defects among medical professionals and public health officials. This is so in spite of the fact that the global prevalence of these conditions seems higher than in the developed world and that limited resources enhance the burden on individuals, families and populations. Furthermore, as a consequence of recent advances in medical genetics, demand for genetic services has increased, reinforcing the need for programs for the management and prevention of genetic diseases and birth defects, especially at primary health care level. An overview of these issues in Brazil is presented here, with information on the health system, the evolution of medical and clinical genetics in the country, and the situation of medical and clinical genetic services. We discuss proposals for implementing appropriate, ethically acceptable and equitable clinical genetic services for the Brazilian population.  相似文献   

7.
A shear impact energy model (SIEM) of erosion suitable for both dilute and dense particle flows is proposed based on the shear impact energy of particles in discrete element method (DEM) simulations. A number of DEM simulations are performed to determine the relationship between the shear impact energy predicted by the DEM model and the theoretical erosion energy. Simulation results show that nearly one-quarter of the shear impact energy will be converted to erosion during an impingement. According to the ratio of the shear impact energy to the erosion energy, it is feasible to predict erosion from the shear impact energy, which can be accumulated at each time step for each impingement during the DEM simulation. The total erosion of the target surface can be obtained by summing the volume of material removed from each impingement. The proposed erosion model is validated against experiment and results show that the SIEM combined with DEM accurately predicts abrasive erosions.  相似文献   

8.
李艺  陈义良 《力学学报》2003,35(2):147-152
对最小均方差估计条件在构造混合模型中的应用作了进一步的讨论,证明了最小均方差条件可以代替工方程作为推导混合模型的约束条件,同时得到了混合项的一个严格的展开式。作为一般情况的一个特例,重新得到了NLIME模型,最后利用NLIEM模型计算了两个基本流场,并和IEM模型的计算结果作了比较。进一步表明了NLIEM模型的优越性。  相似文献   

9.
OBJECTIVE: To conduct a survey in seven European cancer genetics centres to compare service provision, organisation and practices for familial breast and colon cancer consultations and testing. Information was obtained on aspects of services both nationally and locally. METHODS: A detailed survey questionnaire was adapted collaboratively to obtain the required information. Initial survey data were collected within each centre and interim results were discussed at two European Workshops. Where differences in practice existed, details were clarified to ensure accuracy and adequacy of information. Participating centres were Haifa (Israel), Hannover (Germany), Leiden (The Netherlands), Leuven (Belgium), Manchester (UK), Marseille (France) and Milan (Italy), representing countries with populations ranging from 6.5 to 80 million. RESULTS: The European countries diverged in regard to the number of cancer genetics centres nationally (from 8 in Belgium to 37 in France), and the average population served by each centre (from 0.59 million in Israel to 3.32 million in Italy). All centres offered free care at the point of access, but referral to specialist care varied according to national health care provision. At a centre level, staff roles varied due to differences in training and health care provision. The annual number of counsellees seen in each participating centre ranged from 200 to over 1,700. Access to breast surveillance or bowel screening varied between countries, again reflecting differences in medical care pathways. These countries converged in regard to the wide availability of professional bodies and published guidelines promoting aspects of service provision. Similarities between centres included provision of a multidisciplinary team, with access to psychological support, albeit with varying degrees of integration. All services were dominated (70-90%) by referrals from families with an increased risk of breast cancer despite wide variation in referral patterns. Collection of pedigree data and risk assessment strategies were broadly similar, and centres used comparable genetic testing protocols. Average consultation times ranged between 45 and 90 min. All centres had access to a laboratory offering DNA testing for breast and bowel cancer-predisposing genes, although testing rates varied, reflecting the stage of service development and the type of population. Israel offered the highest number of genetic tests for breast cancer susceptibility because of the existence of specific founder mutations, in part explaining why the cancer genetics service in Haifa differed most from the other six. CONCLUSION: Despite considerable differences in service organisation, there were broad similarities in the provision of cancer genetic services in the centres surveyed.  相似文献   

10.
随着我国高速列车的发展, 针对其运营维护中的故障预测与健康管理问题日益受到关注. 轴箱轴承是高速列车走行部中的关键旋转部件, 在复杂的轮轨相互作用下极易出现由疲劳、过载等原因导致的失效, 影响列车的行车效率和运行安全. 而现有诊断方法和技术难以满足高速列车动态化、系统化的安全保障需求, 亟待进一步发展轴箱轴承健康监测和诊断技术. 首先, 介绍了工程中维修检测、轨边监测和车载监测系统的主要内容和发展现状. 然后, 从动力学正、反问题两个方面, 分析和总结了在轴箱轴承的理论建模方法和轴箱轴承与列车耦合系统的动态特性分析、基于先进信号处理技术和机器学习技术的诊断方法等方面的研究思路和研究进展. 最后, 对轴箱轴承健康监测与故障诊断技术的发展趋势进行了展望, 评述了在指导列车故障预测与健康管理方面的不足.   相似文献   

11.
A panel of individuals from diverse ethnocultural backgrounds and representing a variety of genetic disorders presented their consumer perspectives on genetic programs, testing and services. Their remarks emphasized how misunderstanding and miscommunication between health care professionals and many of the populations for whom they provide services can lead to unfilled genetic service needs. Panelists recommended that health care professionals become more aware and knowledgeable about the diversity of customs, beliefs and cultures of those receiving their services. Only by building a foundation of trust and mutual respect will genetic testing, research and services become more accessible to individuals from diverse populations, their families and their communities.  相似文献   

12.
Some epidemiologists and geneticists claim that integrating genetics into public health policies and programs is necessary and unavoidable. OBJECTIVE: To examine the extent to which further integration of public health and genetics is warranted. METHODS: Synthesis of the literature in four areas: research, genetic services, regulation, and education. The analysis is limited to human genetics. RESULTS: Public support for basic genetic research has and will continue to lead to new applications and to further understanding of human origins and dispersions. Some applied research, particularly for genetic risk factors for common complex diseases, has low yield and is better supported by private funds. The only genetic service for which a public health role is paramount is newborn screening. With the patenting of genes, and the proliferation of commercial interests in genetic tests and directly advertising them to the public, regulation by public health agencies is increasingly important. As most genetic testing and other services will be provided in the personal health care system, education about genetics is best left to the educational and medical systems. Public health practitioners should be aware of the limitations of genetic tests. CONCLUSIONS: There is little need for further integration of genetic services and education into public health especially in countries in which public and private health services are dichotomized. Newborn screening and follow-up, however, are most safely and effectively provided under public health auspices. The most important area for strengthening the public health role is in the regulation of genetic tests and other genetic services provided primarily by the private sector. Continued support for basic genetic research is needed.  相似文献   

13.
In this paper, the detailed two-dimensional infinite element method (IEM) formulation with infinite element (IE)–finite element (FE) coupling scheme for investigating mode I stress intensity factor in elastic problems with imbedded geometric singularities (e.g. cracks) is presented. The IE–FE coupling algorithm is also successfully extended to solve multiple crack problems. In this method, the domain of the primary problem is subdivided into two sub-domains modeled separately using the IEM for the multiple crack sub-domain, and the FEM for the uncracked sub-domain. In the IE sub-domain, the similarity partition concept together with the IEM formulation are employed to automatically generate a large number of infinitesimal elements, layer by layer, around the tip of each crack. All degrees of freedom related to the IE sub-domain, except for those associated with the coupling interface, are condensed and transformed to form a finite master IE for each crack with master nodes on sub-domain boundary only. All of the stiffness matrices constructed in the IE sub-domains are assembled into the system stiffness matrix for the FE sub-domain. The resultant FE solution with a symmetrical stiffness matrix, having the singularity effect of imbedded cracks in IEs, is required only for solving multiple crack problems.Using these efficient numerical techniques a very fine mesh pattern can be established around each crack tip without increasing the degree of freedom of the global FEM solution. One is easily allowed to conduct parametric analyses for various crack sizes without changing the FE mesh. Numerical examples are presented to show the performance of the proposed method and compared with the corresponding known results where available.  相似文献   

14.
The surge of information generated by the Human Genome Project has left many health professionals and their patients struggling to understand the role of genetics in health and disease. To aid the lay public and health professionals, the US National Library of Medicine developed an online resource called 'Genetics Home Reference' (GHR), located at http://ghr.nlm.nih.gov/. Launched in April 2003, GHR's goal is to help the public interpret the health implications of the Human Genome Project. It bridges the clinical questions of consumers and the rich technical data emerging from the sequenced human genome. The GHR web site is designed for easy navigation among summaries for genetic conditions and the related gene(s) and chromosome(s). This design strategy enhances the user's appreciation of how genes, chromosomes, and conditions are interrelated.  相似文献   

15.
16.
Screw conveyors are extensively used in modern industry such as metallurgy, architecture and pharmaceutical due to their high-efficiency in the transportation of granular materials. And substantial efforts have been devoted to the study of the screw conveyors. Numerical method is an effective way to study screw conveyor. However, previous studies have mainly focused in the regime of spherical particles while the in-depth investigations for non-spherical particles that should be the most encountered in practical applications are still limited. In view of the above situations, discrete element method (DEM), which has been widely accepted in simulating the discrete systems, is utilized to investigate the conveying process of non-spherical particles in a horizontal screw conveyor, with particles being modeled by super-ellipsoids. In addition, a wear model called SIEM (Shear Impact Energy Model) is incorporated into DEM to predict the wear of screw conveyor. The DEM simulation results demonstrate that the particle shape is influential for the flow behaviors of particles and the wear of conveyor. The conveying performance evaluated quantitatively of both mass flow rate and power consumption is subsequently obtained to investigate the effect of sphericity of particle with different operation parameters. Moreover, particle collision frequency and collision energy consumption are acquired to investigate the possible particle breakage between particles and screw blade. The comparisons between particle–particle collision and particle–wall collision reveal that particles with large shape index have more possibility to be damaged in particle–wall impingement.  相似文献   

17.
OBJECTIVES: This review describes the methods and results of the Hungarian periconceptional service consisting of counselling, examinations and medical interventions. (The term periconceptional is used instead of preconceptional because the early postconceptional period is also involved to this service.) METHODS: The service was based on three steps: check-up examination of reproductive health (i.e., preconceptional screenings), a 3-month preparation for conception, dispensed and/or supervised by qualified nurses, and a better protection in early pregnancy for the most sensitive early development of the embryo for voluntary and eligible couples. RESULTS: Experiences from the coordinating centre of the Hungarian periconceptional service are summarized between February 1, 1984, and January 31, 1999, thus 15 years. Participants with positive family histories, case histories and subjects with genito-urinary infections had a more effective flow towards secondary care. Infertile couples were diagnosed and treated sooner. The periconceptional service is effective for the introduction of periconceptional folic acid-containing multivitamin supplementation and for the reduction of smoking and alcohol consumption in females in the preconceptional period. The rate of major congenital abnormalities (20.6 per 1,000) was significantly lower than expected. CONCLUSIONS: The periconceptional service is feasible and has many benefits. Thus, proper preparation for conception is the earliest and probably the most important effort to prevent genetic diseases.  相似文献   

18.
Microdeformation patterns of lamellar TiAl specimens with various grain sizes under uniaxial tension are mapped using the micro/nano experimental mechanics technique called SIEM (Speckle Interferometry w ith Electron Microscopy). The stress–strain relationships were obtained from deformations within decreasing areas ranging from mm2 to μm2. We found that the stress–strain relationship of the material depends on the size of strain measuring area in relation to the grain size. The stiffness at a grain boundary can be as large as 7–10 times more than that of the grain itself. From the data obtained so far, it seems that the traditional way of using PST (polysynthetically twinned) single crystal to predict polycrystalline behavior may not be appropriate.  相似文献   

19.
分区界面元-有限元-无限元混合模型   总被引:6,自引:1,他引:5  
利用界面元良好的相容性,引入过渡界面元的概念.实现了界面元与有限元二种数值计算方法的结合,并提出了一种界面元-有限元-无限元混合模型。这种混合模型既可以发挥界面元计算精度高、适用于不连续变形等优点.又能够充分利用有限元的计算效率和无限元方便处理无限域介质的特点,较为和谐地解决了计算精度和计算效率的矛盾。数值算例表明,本文所建立的混合模型的有效性,揭示此类混合模型具有广阔的工程应用前景。  相似文献   

20.
For an emerging field such as Public Health Genetics, the partnerships that will be developed with stakeholders are of strategic importance, since they may affect long-term impact on policy-making. A concrete example in the field of health technology assessment in genetics was chosen to illustrate how the context in which scientific advisory bodies operate and the nature of partnerships developed over time influence the impact on decision-making at different levels, from the micro (professional) level through the meso (institutional) level to the macro (policy) level. As pointed out in the knowledge transfer literature, impact is not only reflected by instrumental use of knowledge, but also by problem-framing and strategic use of knowledge. Solid partnerships at the micro level, with researchers and health care professionals, are essential to build credibility and trust, and they lay the groundwork for contextualized and relevant advice and potential impact at the policy level. Even though maintaining the necessary critical distance with respect to all stakeholders is easier for institutions that are at arm's length from government, achieving the right balance between an institution's independence and service relationship is a real challenge.  相似文献   

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