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1.
Objective: To evaluate the effect ofpreimplantation genetic diagnosis (PGD) conducted for women who had Down syndrome pregnancy previously. Methods: Trisomy 21 was diagnosed by using fluorescence in site hybridization (FISH) before embryo transfer in two women who had Down syndrome pregnancies. Each received one or two PGD cycles respectively. Results: Case 1: one PGD cycle was conducted, two oocytes were fertilized and biopsied. One embryo is of trisomy 21 and the other of monosomy 21. No embryo was transferred. Case 2: two PGD cycles were conducted, in total, sixteen oocytes were fertilized and biopsied. Four embryos were tested to be normal, six of trisomy 21, and one of monosomy 21. Five had no signal. Four normal embryos were transferred but no pregnancy resulted. Conclusion: For couples who had pregnancies with Down syndrome previously, PGD can be considered, and has been shown to be an effective strategy.  相似文献   

2.
Mobile phones and other wireless devices that produce electromagnetic fields (EMF) and pulsed radiofrequency radiation (RFR) are widely documented to cause potentially harmful health impacts that can be detrimental to young people. New epigenetic studies are profiled in this review to account for some neurodevelopmental and neurobehavioral changes due to exposure to wireless technologies. Symptoms of retarded memory, learning, cognition, attention, and behavioral problems have been reported in numerous studies and are similarly manifested in autism and attention deficit hyperactivity disorders, as a result of EMF and RFR exposures where both epigenetic drivers and genetic (DNA) damage are likely contributors. Technology benefits can be realized by adopting wired devices for education to avoid health risk and promote academic achievement.  相似文献   

3.
Research has shown that the DNA molecule can not only store genetic information but also serve as a polymeric biomolecule for the fabrication of functional materials. The unique precise molecular recognition capability and sequence programmability, combined with its good biocompatibility and biodegradability, impart the DNA molecule considerable potential for use in the construction of multifunctional materials. Depending on the composition, DNA-based materials have been generally categorized into pure DNA materials that are entirely composed of DNA and hybrid DNA materials that are composed of DNA and other functional compositions. Recently, we have developed a series of DNA-based materials that can be applied in diagnosis and therapy, and this review summarizes the relative work. Although challenges still exist regarding the real applications of DNA-based materials such as the high cost of DNA, the difficulty in scale-up, and the low resistance to nuclease, we believe that these drawbacks will be overcome with the development of technology, and new opportunities will emerge in the field of diagnosis and treatment.  相似文献   

4.
The present study investigated the etiological relationship between two disorders: dyslexia or reading disability (RD) and phonological disorder (PD). These disorders manifest at different ages and have typically been studied by researchers in different disciplines. However, a growing body of evidence suggests that the disorders overlap at symptomatic, cognitive, and etiological levels of analysis. In previous studies, each disorder has been found to be heritable, and there is also evidence that RD and PD run together in families, but no studies to date have documented whether there is a shared genetic influence between the two disorders. The present study examined this question in a sample of RD and non-RD twins. Subjects with a history of PD were identified and the etiological relation between the two disorders was examined. Results indicated that in the present sample, RD and PD are each heritable on their own. Further, even when correcting for RD, the two disorders were found to be coheritable, indicating that the finding of cofamiliality of RD and PD is at least partially driven by genetic influences. The implications of these results for the conceptualization, identification, and treatment of these two disorders are discussed.  相似文献   

5.
The cognitive and behavioral symptoms of nonverbal learning disabilities (NLD) have been described by previous investigators. Nevertheless, we know far less about the potential genetic contributions that may predispose a child to have NLD. An endophenotype model was investigated in 5 samples of children ages 9 to 15 years: NLD (n = 32); reading disorders (RD; n = 59); participants with a psychiatric diagnosis but without a learning disability (n = 55); typically developing controls (n = 31); and children with velocardiofacial syndrome (VCFS), a chromosomal deletion syndrome that has been proposed as being an exemplar of NLD (VCFS + NLD; n = 20). Based on a family genetic interview, the authors' data suggest that children with NLD, RD, or a psychiatric diagnosis have a higher prevalence rate of attention-deficit/hyperactivity disorder (ADHD) and substance abuse/dependence. Psychiatric controls and children with NLD--but not children with RD-- showed higher prevalence rates of familial bipolar disorder.  相似文献   

6.
广西拥有丰富的医药遗传资源和民族传统医学知识,具有开拓东盟市场的知识产权基础和政策支持。由于目前民族中药产品和疾病诊疗方法在知识产权保护方面面临许多困境,而且医药遗传资源和民族传统医学知识不属于知识产权保护范围,给广西民族医药开拓东盟市场增加了不少困难。因此,必须加强对广西民族医药产品的知识产权保护,对遗传资源和传统知识实施特别保护,并加强广西与东盟各国在民族医药领域的知识产权合作。  相似文献   

7.
随着实验方法和研究技术的发展,遗传多样性的研究从形态学水平,细胞学水平,生化水平发展到了DNA分子水平。利用这些分析方法,我们可以有效地研究物种的遗传多样性。通过冬虫夏草分子标记技术的遗传多样性研究,可获取冬虫夏草DNA的遗传标记及检测方法,有效的鉴别其品种和产地,以及在分子水平上研究冬虫夏草的遗传多样性。  相似文献   

8.
在众多的晶体生长的方法中,水热合成包括溶剂热合成由于它的简便经济,成为最有前途的实验方法之一。已经报道水热和溶剂热合成方法合成出来了Sb不同形貌的纳米晶,比如Sb纳米管,Sb纳米线,Sb纳米带束。产物的最终形貌能通过改变反应的参数,比如溶剂、反应温度和时间、表面活性剂和试剂的初始浓度来加以控制。  相似文献   

9.
Biotechnology has opened unprecedented avenues for exploring biological systems. One of the key techniques in genetic engineering is gene transfer, which involves transfer of recombinant DNA into plant cells to generate transgenic plants. Genes and genomes from a wide range of organisms are being manipulated for the benefit of mankind. Application of genetic engineering in agriculture has produced significant achievements such as yield improvement of major food crops.  相似文献   

10.
11.
The role of alcohol or drug use has been underestimated in the etiology and diagnosis of the physical, academic and psychological problems of the college student; so has the fact of being the child of a parent with substance use disorder (SUD). SUD can masquerade behind a multitude of problems seen by college counselors such as depression, anxiety, eating disorders, social and academic difficulties. The price of unrecognized SUD for the student is continued dysfunction. The price for the counselor, floundering therapy. Even when SUD and other or other problem(s) co-exist (dual diagnosis), treatment may still fail (or remain incomplete) if SUD is not identified and treated. The current principles of SUD diagnosis are outlined here with the purpose of raising the consciousness of counselors, deans, doctors, or other health or administrative personnel to the concern of college student SUD so that casualty among students may be minimized. Brief reference is also made to the problems of being the child of an alcoholic or other substance abusing parent.  相似文献   

12.
We studied the allelic frequency distributions and statistical forensic parameters of 21 new short tandem repeat (STR) loci and the amelogenin locus, which are not included in the combined DNA index system (CODIS), in a Russian ethnic minority group from the Inner Mongolia Autonomous Region, China. A total of 114 bloodstain samples from unrelated individuals were extracted and co-amplified with four fluorescence-labeled primers in a multiplex polymerase chain reaction (PCR) system. Using capillary electrophoresis, the PCR products of the 21 STR loci were separated and genotyped. A total of 161 alleles were observed in the Russian ethnic minority group, and corresponding allelic frequencies ranged from 0.0044 to 0.5965. The 21 non-CODIS STR loci of the Russian ethnic minority group were characterized by high genetic diversity and therefore may be useful for elucidating the population’s genetic background, for individual identification, and for paternity testing in forensic practice.  相似文献   

13.
ResearchonGeneticAlgorithmBasedKnowledgeAuto-AcquisitionforFaultDiagnosisZhangXuejiang(张雪江)ZhuXiangyang(朱向阳)ZhongBinglin(钟秉林...  相似文献   

14.
成环恒温扩增法是一种新型的核酸扩增方法,它是在具有解链活性的DNA聚合酶的作用下,以新形成的产物为模板进行自身循环扩增的恒温核酸扩增方法。该方法是Notom i等2000年发明的,由于它与其它的核酸扩增方法相比较,具有更快捷,更敏感,更廉价和能即时判断结果等优点,已经应用到了多种病原核酸的检测上。作者结合研制尤氏泰勒虫核酸检测实践对该方法的原理,用途和应用中的优缺点进行了综述。  相似文献   

15.
In the search for a rapid and reliable method for identification of bacteria in blood and cerebrospinal fluid , we developed a unified set of primers and used them under polymerase chain reaction(PCR) to amplify the spacer regions between the 16s and 23s genes in the prokaryotic rRNA genetic loci . Spacer regions within these loci showed a significant level of length and sequence polymorphism across most of the species lines. A generic pair of priming sequences was selected from highly conserved sequences in the 16s and 23s genes occurring adjacent to these polymorphic regions. This single set of primers and reaction conditions were used for the amplification of the 16s-23s spacer regions for 61 strains of standard bacteria and corresponding clinical isolates belonging to 20 genera and 27 species, including Listeria, Staphylococcus and Salmonella species, et al. When the spacer amplification products were resolved by electrophoresis, the resulting patterns could be used to distinguish most of the bacteria species within the test group, and the amplification products of the clinical isolates clustered at the standard species level. Some species presenting similar pattern were further analyzed by HinfI or AluI digestion or DNA clone and sequences analysis in order to establish the specific 16s-23s rRNA gene spacer regions map. Analysis of 42 blood specimens from septicemic neonates and 6 CSF specimens from suspected purulent meningitis patients by bacterial culture and PCR-RFLP(Restriction Fregament Length Polymorphism) showed that 15 specimens of blood culture were positive(35.7%) in the 42 septicemic neonates; 27 specimens were positive(64.2%) by PCR, and that the positive rate by PCR was significantly higher than that by blood culture(P<0.01). Among the 6 CSF specimens, one specimen found positive by blood culture was also positive by PCR, two found negative by blood culture showed positive by PCR; all three were S.epidermidis according to the DNA map. One C.neoformans found positive by blood culture showed negative by PCR. The remaining two specimens were both negative by PCR and blood culture. These results indicated that the method of detecting bacterial 16s-23s rRNA spacer regions using PCR and RFLP techniques was rapid, sensitive and specific in the detection of bacterial infections; and so, has very important application in the clinical diagnosis of sepsis in neonates.  相似文献   

16.
In recent years, there has been a growing interest in white matter anatomy of the human brain. With advances in brain imaging techniques, the significance of white matter integrity for brain function has been demonstrated in various neurological and psychiatric disorders. As the demand for interpretation of clinical and imaging data on white matter increases, the needs for white matter anatomy education are changing. Because cross‐sectional images and formalin‐fixed brain specimens are often insufficient in visualizing the complexity of three‐dimensional (3D) white matter anatomy, obtaining a comprehensible conception of fiber tract morphology can be difficult. Fiber dissection is a technique that allows isolation of whole fiber pathways, revealing 3D structural and functional relationships of white matter in the human brain. In this study, we describe the use of fiber dissection in combination with plastination to obtain durable and easy to use 3D white matter specimens that do not require special care or conditions. The specimens can be used as a tool in teaching white matter anatomy and structural connectivity. We included four human brains and show a series of white matter specimens of both cerebrum and cerebellum focusing on the cerebellar nuclei and associated white matter tracts, as these are especially difficult to visualize in two‐dimensional specimens and demonstrate preservation of detailed human anatomy. Finally, we describe how the integration of white matter specimens with radiological information of new brain imaging techniques such as diffusion tensor imaging tractography can be used in teaching modern neuroanatomy with emphasis on structural connectivity. Anat Sci Educ. 7: 47–55. © 2013 American Association of Anatomists.  相似文献   

17.
Children may present with reading and/or attentional and/or affective (depressive) disorders in childhood. Although reading problems are more readily identifiable, childhood attentional and affective disorders can be difficult to recognize and diagnose. Here are discussed a number of complex and potentially confusing ways in which reading, attentional and affective disorders may be related: a primary problem in one area may result in problems in another; one disorder may look like another; and/or a child may simultaneously present two or all three primary disorders. Current clinical practice and recent and ongoing research is presented to clarify the changing definitions and potential relationships of these three childhood disorders to aid the process of differential diagnosis.  相似文献   

18.
双生子分析法是人类遗传学研究的经典方法,采用此法进行体质与运动能力的遗传学研究,首先要解决如遗传度公式的选择、双生子卵型的鉴别等基础问题。人类体质与运动能力的遗传学研究已有较长的历史,其领域从经典遗传流行病学发展到分子生物学,研究方法不断更新,人类对体质与运动能力遗传本质有了更深入的了解。  相似文献   

19.
Spinal muscular atrophy (SMA) is a disorder characterized by degeneration of lower motor neurons and occasionally bulbar motor neurons leading to progressive limb and trunk paralysis as well as muscular atrophy. Three types of SMA are rec-ognized depending on the age of onset, the maximum muscular activity achieved, and survivorship: SMA1, SMA2, and SMA3. The survival of motor neuron (SMN) gene has been identified as an SMA determining gene, whereas the neuronal apoptosis inhibitory protein (NAIP) gene is considered to be a modifying factor of the severity of SMA. The main objective of this study was to analyze the deletion of SMN1 and NAIP genes in southern Chinese children with SMA. Here, polymerase chain reaction (PCR) combined with restriction fragment length polymorphism (RFLP) was performed to detect the deletion of both exon 7 and exon 8 of SMNI and exon 5 of NAIP in 62 southern Chinese children with strongly suspected clinical symptoms of SMA. All the 32 SMAI patients and 76% (13/17) of SMA2 patients showed homozygous deletions for exon 7 and exon 8, and all the 13 SMA3 patients showed single deletion of SMN1 exon 7 along with 24% (4/17) of SMA2 patients. Eleven out of 32 (34%) SMA1 patients showed NAIP deletion, and none of SMA2 and SMA3 patients was found to have NAIP deletion. The findings of homozygous deletions of exon 7 and/or exon 8 of SMN1 gene confirmed the diagnosis of SMA, and suggested that the deletion of SMN1 exon 7 is a major cause of SMA in southern Chinese children, and that the NA1P gene may be a modifying factor for disease severity of SMA 1. The molecular diagnosis system based on PCR-RFLP analysis can conveniently be applied in the clinical testing, genetic counseling, prenatal diagnosis and preimplantation genetic diagnosis of SMA.  相似文献   

20.
基因芯片又称DNA微矩阵,是一种分析大量复杂生物样品的有效工具。它可以通过光引导聚合技术、电压打印或人工直接点样制备。光蚀刻技术可以使探针密度达到10^6/cm^2。它们可以被广泛地应用于DNA序列测定、新基因的检测和突变基因的分析。在医学上,基因芯片可以被用于癌症的诊断,传染病疾病如AIDS和肝炎等的早期检测。它在新药开发上也有巨大的市场。  相似文献   

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