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11.
Dr S. is a famous transplant surgeon in the Middle East. He operates "underground" on wealthy patients in different countries, from Israel to Turkey to Russia. The media refer to him as the "Organ Mafia doctor," and patients diagnosed with renal failure speak of him sardonically as "Robin Hood," acknowledging that he takes organs from the poor to give to the rich. But ethical issues of organ trafficking are not limited to marginal private clinics and "Mafia" doctors. All-living related organ transplants in Turkey involve similar ethical dilemmas: many related or nonrelated organ recipients pay their donors, and demand continues to rise. This paper explores practices in state and university hospitals and the ethical dilemmas doctors encounter to understand where and how judicial, cultural, and social categories of "human rights" and "crime" are constructed in our high-tech world.  相似文献   
12.
To further pinpoint the location of the genes for ataxia-telangiectasia on the long arm of chromosome 11, we performed linkage analysis and analysis of recombinants of genetic haplotypes on 14 Turkish families with ataxia-telangiectasia, 12 of which were consanguineous. These studies used more than 25 polymorphic genetic markers spanning a region of the long arm of chromosome 11 that is larger than 50 cM. Seven markers gave significant LOD scores to AT: CJ5, DRD2, CJ208, S144, CD3E, PBGD, and S147, as did haplotypes created with pairs of markers DRD2/CJ5 and S144/CJ208, giving recombination fractions (theta) of 0.00, 0.00, 0.05, 0.08, 0.03, 0.09, 0.07, 0.00, and 0.06, respectively. Monte Carlo analysis of these 14 Turkish families indicated the best location for a single AT gene to be within a 6 cM sex-averaged (3 cM male-specific) interval defined by STMY and CJ77; this was three times more likely than the next most likely location (peak III) at the DRD2 locus. The analysis also revealed a peak (peak II) between S147 and S133, which may represent the complementation group D gene. Recombinant analysis of haplotypes also localized an AT locus to the STMY-CJ77 interval. Taken together, these results suggest that at least two distinct AT loci exist (ATA and ATD) at 11q22-23, with perhaps a third locus, ATC, located very near to the ATA gene. This genetic heterogeneity further complicates plans to isolate the major ATA and ATC genes and to begin identifying AT carriers in the general population.  相似文献   
13.
云南切梢小蠹Tomicus yunnanensis(Kirkendall and Faccoli)是一种蛀害云南松Pinus yunnanensis的本土害虫.为深入了解其寄主选择机制,用顶空动态法和浸提法分别提取了初侵染云南松针叶和松脂的挥发性化合物,并用气相色谱-质谱联用技术(GC-MS)、气相色谱-昆虫触角电位测量系统(GC-EAD)、生测法鉴定和筛选了对云南切梢小蠹具有活性功能的成分.结果表明:云南松针叶和松脂中共有18种化合物,均为萜烯类物质,但两者化学成分的构成有显著差异.针叶中单萜类占99.98%,主要是 α-蒎烯(80.82%)、β-蒎烯(8.78%)、D-柠檬烯(4.77%)、莰烯(2.86%)和β-月桂烯(1.42%),而松脂以单萜类和双萜类为主,前者以α-蒎烯(21.38%)、3-蒈烯(21.42%)和异松油烯(2.78%)为主要成分,后者仅有长叶松酸(51.13%)一种.云南切梢小蠹对α-蒎烯、β-蒎烯、3-蒈烯、γ-萜品烯和4-烯丙基苯甲醚有触角电位反应,其中α-蒎烯、3-蒈烯和γ-萜品烯具引诱作用,4-烯丙基苯甲醚和β-蒎烯则为驱避功能.研究可为开发植物源引诱剂或与性信息素结合进行种群监测和诱杀提供科学依据.  相似文献   
14.
15.
The biological role in vivo of the homologous CD3gamma and delta invariant chains within the human TCR/CD3 complex is a matter of debate, as murine models do not recapitulate human immunodeficiencies. We have characterized, in a Turkish family, two new patients with complete CD3gamma deficiency and SCID symptoms and compared them with three CD3gamma-deficient individuals belonging to two families from Turkey and Spain. All tested patients shared similar immunological features such as a partial TCR/CD3 expression defect, mild alphabeta and gammadelta T lymphocytopenia, poor in vitro proliferative responses to Ags and mitogens at diagnosis, and very low TCR rearrangement excision circles and CD45RA(+) alphabeta T cells. However, intrafamilial and interfamilial clinical variability was observed in patients carrying the same CD3G mutations. Two reached the second or third decade in healthy conditions, whereas the other three showed lethal SCID features with enteropathy early in life. In contrast, all reported human complete CD3delta (or CD3epsilon) deficiencies are in infants with life-threatening SCID and very severe alphabeta and gammadelta T lymphocytopenia. Thus, the peripheral T lymphocyte pool was comparatively well preserved in human CD3gamma deficiencies despite poor thymus output or clinical outcome. We propose a CD3delta > CD3gamma hierarchy for the relative impact of their absence on the signaling for T cell production in humans.  相似文献   
16.
In this study, seed germination percentages, effects on phases of mitosis and α-amylase enzyme activity of lentil seeds treated with four different concentrations (0.25, 0.5, 1 and 1.5%) of Fusilade (Fluazifop-p-butyl) were determined. Median EC (effective concentration) values were calculated according to seed germination percentages after treatment for 72 h. Germination percentages of primary lentil roots decreased with increasing Fusilade concentrations. Cytological observations showed that the mitotic frequency in root meristematic cells were decreased parallel to the increase in concentrations and all Fusilade concentrations applied decreased the activity of α-amylase enzyme in lentil seeds. The obtained results indicate that the herbicide Fusilade had the ability to cause reduction in seed germination, mitotic frequency and also α-amylase activity of lentil seeds.  相似文献   
17.
Chromosomal Instability in Callus Culture of Pisum sativum   总被引:2,自引:0,他引:2  
A study on the variation in chromosome number and structure of the cells from 45-days-old embryonal axis explant callus tissue of Pisum sativum L. of four genotypes was undertaken. The chromosome number showed a wide range of variation, however, the majority of cells studied were observed to be diploid (2n= 2x= 14) in nature. Among the numerical aberrations induced, tetraploid cells were the most frequent as compared to aneuploid cells of cells with a higher ploidy level. The frequency of fragments and bridges were highest among other structural changes. The composition and concentration of growth regulators was found to effect chromosomal instability whereas there was no effect of genotype.  相似文献   
18.
An undifferentiated lymphocytic lymphoma of mesenteric lymph nodes occurred in a young boy with ataxia-telangiectasia. Two independent tests, Epstein-Barr virus (EBV)-cRNA/DNA hybridisation and EBV DNA/DNA reassociation kinetic analysis, showed 53 and 68 EBV genome equivalents per cell respectively, which was compatible with an EBV-genome-carrying tumour. Whether this was a polyclonal lymphoproliferation or a monoclonal tumour could not be determined owing to lack of suitable material. The presence of EBV genomes should be sought in lymphomas arising in ataxia-telangiectasia and other immunodeficiencies.  相似文献   
19.
We recently mapped the gene for ataxia-telangiectasia group A (ATA) to chromosome 11q22-23 by linkage analysis, using the genetic markers THY1 and pYNB3.12 (D11S144). The most likely order was cent-AT-S144-THY1. The present paper describes further mapping of the AT locus by means of a panel of 10 markers that span approximately 60 cM in the 11q22-23 region centered around S144 and THY1. Location scores indicate that three contiguous subsegments within the [S144-THY1] segment, as well as three contiguous segments telomeric to THY1, are each unlikely to contain the AT locus, while the more centromeric [STMY-S144] segment is most likely to contain the AT locus. These data, together with recent refinements in the linkage and physical maps of 11q22-23, place the AT locus at 11q23.  相似文献   
20.
New metatherian petrosal bones from the mid to Late Palaeocene of Itaboraí, belonging to three morphotypes (VI, VII, and VII), are formally described and compared to fossil and extant taxa known by their auditory region. An attempt at assigning petrosal types to tooth‐based taxa from Itaboraí was made by combining parsimony and morphometric methods. The first large scale phylogenetic analysis of the Itaboraían metatherians, involving basicranial and dental characters in a larger number of taxa, is provided here and is at the basis of a systematic revision of the metatherians from Itaboraí. The combination of morphometric and cladistic analyses helps in understanding the affinities between the petrosals and the tooth‐based taxa. The metatherians from Itaboraí were taxonomically diverse, belonging to each of the most important radiations in marsupial evolutionary history (Didelphimorphia, Paucituberculata, Eometatheria). The inclusion of Palaeocene taxa in the crown group Marsupialia and above all in the Eometatheria radiation points to an early emergence of these clades in South America and corroborates the main molecular hypotheses. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 159 , 746–784.  相似文献   
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