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1.
A 46-year-old man with pentazocine-induced agranulocytosis is described. In previously reported cases of a complete absence of mature neutrophils in the peripheral blood and bone marrow the patients had undergone marrow-depressing treatment with radiation and antineoplastic drugs. This case is unique in that the patient had complete agranulocytosis without predisposing factors. 相似文献
2.
Chromosome 16-specific repetitive DNA sequences that map to chromosomal regions known to undergo breakage/rearrangement in leukemia cells. 总被引:4,自引:0,他引:4
Human chromosome 16-specific low-abundance repetitive (CH16LAR) DNA sequences have been identified during the course of constructing a physical map of this chromosome. At least three CH16LAR sequences exist and they are interspersed, in small clusters, over four regions that constitute more than 5% of the chromosome. CH16LAR sequences were observed in one unusually large cosmid contig (number 55), where the ordering of clones was difficult because these sequences led to false overlaps between noncontiguous clones. Contig 55 contains 78 clones, or approximately 2% of all the clones contained within the present cosmid contig physical map. Fluorescent in situ hybridization of multiple clones, including cosmid and YAC contig 55 clones, mapped the four CH16LAR-rich regions to bands p13, p12, p11, and q22. These regions are of biological interest since the pericentric inversion and the interhomologue translocation breakpoints commonly found in acute nonlymphocytic leukemia (ANLL) subtype M4 fall within these bands. Sequence analysis of a 2.2-kb HindIII fragment from a cosmid containing a CH16LAR sequence indicated that one of the CH16LAR elements is similar to a minisatellite sequence in that the core repeat is only 40 bp in length. Additional characterization of other repetitive elements is in progress. 相似文献
3.
Variation in the ribosomal internal transcribed spacers (ITS1 and ITS2) among eight taxa of the Mimulus guttatus species complex 总被引:1,自引:0,他引:1
The internal transcribed spacer region (ITS1 and ITS2) of the 18S-25S
nuclear ribosomal DNA sequence and the intervening 5.8S region were
sequenced from three individuals in each of eight taxa of the Mimulus
guttatus species complex. Three discrete variants, or "types," of ITS
sequences were found, among which 30%-40% of sites differed, compared with
1%-2% within types. Dot plots indicate that these types were not related by
conspicuous rearrangements or inversions. More than one ITS type was often
found in the same taxon, and two of three ITS types span species
boundaries, indicating their presence prior to speciation. These ITS
sequences showed essentially no positional homology with the nearest
sequenced relative, tomato. In contrast, the 5.8S region was relatively
unvaried, with 8 of 162 sites varied in the sample among all eight taxa.
The phylogeny inferred by the most common ITS sequence type, rooted by the
two other ITS types, agreed with isozymes in showing the distinctness of M.
nudatus, M. laciniatus, and M. tilingii from the other five taxa.
相似文献
4.
5.
David L. Doggett Mei-Ping Chang Takashi Makinodan Bernard L. Strehler 《Molecular and cellular biochemistry》1981,37(3):137-156
Summary We begin with a brief discussion of the importance and advantages of immune studies to the problem of aging. This is followed
by a short over-view of immune system aging at the systemic level. The major portion of the article is a review of observations,
both at the cellular and molecular level, of changes in aging immune cells, with sections on intercellular communication,
membrane phenomena, cyclic nucleotides, and molecular genetic changes.
Publication number 043 from Wadsworth GRECC. 相似文献
6.
7.
大中型食肉动物肇事事件导致人类与野生动物关系恶化,给生物多样性保护工作带来巨大的挑战。若尔盖湿地是我国三大湿地之一,湿地、草原分布广泛,生物多样性丰富,畜牧业发达,但近年来狼(Canis lupus)捕杀牲畜的肇事事件时有发生。为了解若尔盖野生狼肇事件的空间分布以及牧民对人-狼冲突管理的看法,本研究于2022年对若尔盖县13个乡镇83个行政村进行走访调查。结果表明:(1)多数受访者(66.0%)认为在过去5年内,若尔盖县野生狼数量有所增加;(2)狼肇事事件具有明显的空间分异性,最严重的是包座乡。包座乡临近山区,该区域牧场面积广阔、牧民饲养牲畜数量多等原因导致该镇发生狼肇事事件较多;(3)对于狼肇事,绝大多数牧民(85.0%)更希望采取经济补偿或者驱赶措施,只有少数牧民(9.4%)希望采取捕杀的措施;(4)影响牧民对狼肇事管理措施的偏好因子中,受教育程度、年龄、民族以及被杀牲畜数量有显著影响。建议加强狼种群监测管理,采取措施减少狼捕杀牲畜,优化补偿机制,缓解当地牧民与狼之间的矛盾。本研究为当前若尔盖县野生动物保护和管理决策提供了依据,对其他地区大型食肉动物与当地居民冲突管理具有借鉴意义。 相似文献
8.
9.
Marie Nancy Séraphin Michael Lauzardo Richard T. Doggett Jose Zabala J. Glenn Morris Jr. Jason K. Blackburn 《PloS one》2016,11(4)
BackgroundTuberculosis (TB) is caused by members of the Mycobacterium tuberculosis complex (MTBC). Although the MTBC is highly clonal, between-strain genetic diversity has been observed. In low TB incidence settings, immigration may facilitate the importation of MTBC strains with a potential to complicate TB control efforts.MethodsWe investigated the genetic diversity and spatiotemporal clustering of 2,510 MTBC strains isolated in Florida, United States, between 2009 and 2013 and genotyped using spoligotyping and 24-locus MIRU-VNTR. We mapped the genetic diversity to the centroid of patient residential zip codes using a geographic information system (GIS). We assessed transmission dynamics and the influence of immigration on genotype clustering using space-time permutation models adjusted for foreign-born population density and county-level HIV risk and multinomial models stratified by country of birth and timing of immigration in SaTScan.Conclusions/SignificanceAlmost five percent of TB cases reported in Florida during 2009–2013 were potentially due to recent transmission. Improvements to TB screening practices among the prison population and recent immigrants are likely to impact TB control. Due to the monomorphic nature of available markers, whole genome sequencing is needed to conclusively delineate recent transmission events between U.S. and foreign-born persons. 相似文献
10.
Thickening of the integument as a mechanism of resistance to insecticides is a well recognised phenomenon in the insect world and, in recent times, has been found in insects exhibiting pyrethroid-resistance. Resistance to pyrethroid insecticides in the common bed bug, Cimex lectularius L., is widespread and has been frequently inferred as a reason for the pest’s resurgence. Overexpression of cuticle depositing proteins has been demonstrated in pyrethroid-resistant bed bugs although, to date, no morphological analysis of the cuticle has been undertaken in order to confirm a phenotypic link. This paper describes examination of the cuticle thickness of a highly pyrethroid-resistant field strain collected in Sydney, Australia, in response to time-to-knockdown upon forced exposure to a pyrethroid insecticide. Mean cuticle thickness was positively correlated to time-to-knockdown, with significant differences observed between bugs knocked-down at 2 hours, 4 hours, and those still unaffected at 24 hours. Further analysis also demonstrated that the 24 hours survivors possessed a statistically significantly thicker cuticle when compared to a pyrethroid-susceptible strain of C. lectularius. This study demonstrates that cuticle thickening is present within a pyrethroid-resistant strain of C. lectularius and that, even within a stable resistant strain, cuticle thickness will vary according to time-to-knockdown upon exposure to an insecticide. This response should thus be considered in future studies on the cuticle of insecticide-resistant bed bugs and, potentially, other insects. 相似文献