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51.
Riassunto Viene descritto un metodo che consente di isolare una buona quantità di linfociti, completamente privi di eritrociti e di piastrine. Il metodo é basato sull'azione emolitica del NH4Cl e sulla ritensione dei granulociti e delle piastrine ad opera del cotone. Questo metodo è risultato molto soddisfacente anche per isolare le cellule di tipo mielocitario dai granulociti dal sangue di pasienti con leucemia mieloide cronica. 相似文献
52.
用脸谱图对太子河本溪市区段河流沉积物中重金属污染进行评价的研究 总被引:9,自引:0,他引:9
本文将沉积学原理及国际上新发展的两种重金属污染评价方法与多变量的图表示法——脸谱图相结合,对太子河本溪市区段河道沉积物中重金属的污染状况及潜在生态危害进行了综合性的评价研究。从脸谱图上可以直观地看出各采样点重金属的污染情况和潜在生态危害程度。从研究结果可以看出,太子河本溪市区段河道沉积物中重金属的污染是很严重的。 相似文献
53.
Nocentini S Reginensi D Garcia S Carulla P Moreno-Flores MT Wandosell F Trepat X Bribian A del Río JA 《Cellular and molecular life sciences : CMLS》2012,69(10):1689-1703
Newly generated olfactory receptor axons grow from the peripheral to the central nervous system aided by olfactory ensheathing
cells (OECs). Thus, OEC transplantation has emerged as a promising therapy for spinal cord injuries and for other neural diseases.
However, these cells do not present a uniform population, but instead a functionally heterogeneous population that exhibits
a variety of responses including adhesion, repulsion, and crossover during cell–cell and cell–matrix interactions. Some studies
report that the migratory properties of OECs are compromised by inhibitory molecules and potentiated by chemical gradients.
Here, we demonstrated that rodent OECs express all the components of the Nogo receptor complex and that their migration is
blocked by myelin. Next, we used cell tracking and traction force microscopy to analyze OEC migration and its mechanical properties
over myelin. Our data relate the decrease of traction force of OEC with lower migratory capacity over myelin, which correlates
with changes in the F-actin cytoskeleton and focal adhesion distribution. Lastly, OEC traction force and migratory capacity
is enhanced after cell incubation with the Nogo receptor inhibitor NEP1-40. 相似文献
54.
Fourteen freshwater ostracod species collected from 24 springs in Nevada, Idaho, and Oregon between 1991 and 1994 were classified. Their ecology, based on major water parameters (i.e., temperature, dissolved oxygen, pH, conductivity), and biogeographical distribution in North America were studied. Among these 14 species, 9 ( Ilyocypris bradyi , I. gibba , Darwinula stevensoni , Candona candida , Heterocypris incongruens , Herpetocypris reptans , H. chevreuxi , Prionocypris canadensis , P. longiforma ) are new records for Nevadas ostracod fauna, while 3 ( H. reptans , P. canadensis , and Cypria turneri ) are new species for Oregon. H. reptans , P. canadensis , and Heterocypris salina are also recorded as new for the ostracod literature of Idaho. Scottia pseudobrowniana , collected from Nevada, is a new ostracod species for the United States. The occurrence of 5 Holarctic species in the northern Great Basin area may suggest a possible historical relationship with the European ostracod fauna. 相似文献
55.
Bass AJ Lawrence MS Brace LE Ramos AH Drier Y Cibulskis K Sougnez C Voet D Saksena G Sivachenko A Jing R Parkin M Pugh T Verhaak RG Stransky N Boutin AT Barretina J Solit DB Vakiani E Shao W Mishina Y Warmuth M Jimenez J Chiang DY Signoretti S Kaelin WG Spardy N Hahn WC Hoshida Y Ogino S Depinho RA Chin L Garraway LA Fuchs CS Baselga J Tabernero J Gabriel S Lander ES Getz G Meyerson M 《Nature genetics》2011,43(10):964-968
Prior studies have identified recurrent oncogenic mutations in colorectal adenocarcinoma and have surveyed exons of protein-coding genes for mutations in 11 affected individuals. Here we report whole-genome sequencing from nine individuals with colorectal cancer, including primary colorectal tumors and matched adjacent non-tumor tissues, at an average of 30.7× and 31.9× coverage, respectively. We identify an average of 75 somatic rearrangements per tumor, including complex networks of translocations between pairs of chromosomes. Eleven rearrangements encode predicted in-frame fusion proteins, including a fusion of VTI1A and TCF7L2 found in 3 out of 97 colorectal cancers. Although TCF7L2 encodes TCF4, which cooperates with β-catenin in colorectal carcinogenesis, the fusion lacks the TCF4 β-catenin-binding domain. We found a colorectal carcinoma cell line harboring the fusion gene to be dependent on VTI1A-TCF7L2 for anchorage-independent growth using RNA interference-mediated knockdown. This study shows previously unidentified levels of genomic rearrangements in colorectal carcinoma that can lead to essential gene fusions and other oncogenic events. 相似文献
56.
Darío Acuña-Castroviejo Germaine Escames Carmen Venegas María E. Díaz-Casado Elena Lima-Cabello Luis C. López Sergio Rosales-Corral Dun-Xian Tan Russel J. Reiter 《Cellular and molecular life sciences : CMLS》2014,71(16):2997-3025
Endogenous melatonin is synthesized from tryptophan via 5-hydroxytryptamine. It is considered an indoleamine from a biochemical point of view because the melatonin molecule contains a substituted indolic ring with an amino group. The circadian production of melatonin by the pineal gland explains its chronobiotic influence on organismal activity, including the endocrine and non-endocrine rhythms. Other functions of melatonin, including its antioxidant and anti-inflammatory properties, its genomic effects, and its capacity to modulate mitochondrial homeostasis, are linked to the redox status of cells and tissues. With the aid of specific melatonin antibodies, the presence of melatonin has been detected in multiple extrapineal tissues including the brain, retina, lens, cochlea, Harderian gland, airway epithelium, skin, gastrointestinal tract, liver, kidney, thyroid, pancreas, thymus, spleen, immune system cells, carotid body, reproductive tract, and endothelial cells. In most of these tissues, the melatonin-synthesizing enzymes have been identified. Melatonin is present in essentially all biological fluids including cerebrospinal fluid, saliva, bile, synovial fluid, amniotic fluid, and breast milk. In several of these fluids, melatonin concentrations exceed those in the blood. The importance of the continual availability of melatonin at the cellular level is important for its physiological regulation of cell homeostasis, and may be relevant to its therapeutic applications. Because of this, it is essential to compile information related to its peripheral production and regulation of this ubiquitously acting indoleamine. Thus, this review emphasizes the presence of melatonin in extrapineal organs, tissues, and fluids of mammals including humans. 相似文献
57.
Gerardo?Carranza Raquel?Casta?o Mónica?L.?Fanarraga Juan?Carlos?Villegas Jo?o?Gon?alves Jesus?Avila Marco?Marenchino Ramón?Campos-Olivas Guillermo?Montoya Juan?Carlos?ZabalaEmail author 《Cellular and molecular life sciences : CMLS》2013,70(2):357-371
Tubulin cofactors (TBCs) participate in the folding, dimerization, and dissociation pathways of the tubulin dimer. Among them, TBCB and TBCE are two CAP-Gly domain-containing proteins that together efficiently interact with and dissociate the tubulin dimer. In the study reported here we showed that TBCB localizes at spindle and midzone microtubules during mitosis. Furthermore, the motif DEI/M-COO? present in TBCB, which is similar to the EEY/F-COO? element characteristic of EB proteins, CLIP-170, and α-tubulin, is required for TBCE–TBCB heterodimer formation and thus for tubulin dimer dissociation. This motif is responsible for TBCB autoinhibition, and our analysis suggests that TBCB is a monomer in solution. Mutants of TBCB lacking this motif are derepressed and induce microtubule depolymerization through an interaction with EB1 associated with microtubule tips. TBCB is also able to bind to the chaperonin complex CCT containing α-tubulin, suggesting that it could escort tubulin to facilitate its folding and dimerization, recycling or degradation. 相似文献
58.
就太原市现行集贸市场活禽屠宰方式的弊端进行了分析,提出了实施禽类屠宰工厂化,实行定点屠宰,集中检疫,统一管理,防止病害禽类产品流入市场,杜绝私屠滥宰对城市环境造成污染的具体对策措施。 相似文献
59.
本文研究了测定天然水中痕量铅的微分电位溶出法。该法检测下限为0.1ug·L~(-1)pb,在0~10ug·L~(-1)浓度段有良好的线性关系,测浓度为3~4ug·L~(-1)pb的试样的相对标准偏差为5%,一般水样回收率为93~107%。用于自来水、井水、河水、湖水中痕量铅的直接快速测定,结果令人满意。 相似文献
60.
First insights into the biodiversity and biogeography of the Southern Ocean deep sea 总被引:1,自引:0,他引:1
Brandt A Gooday AJ Brandão SN Brix S Brökeland W Cedhagen T Choudhury M Cornelius N Danis B De Mesel I Diaz RJ Gillan DC Ebbe B Howe JA Janussen D Kaiser S Linse K Malyutina M Pawlowski J Raupach M Vanreusel A 《Nature》2007,447(7142):307-311
Shallow marine benthic communities around Antarctica show high levels of endemism, gigantism, slow growth, longevity and late maturity, as well as adaptive radiations that have generated considerable biodiversity in some taxa. The deeper parts of the Southern Ocean exhibit some unique environmental features, including a very deep continental shelf and a weakly stratified water column, and are the source for much of the deep water in the world ocean. These features suggest that deep-sea faunas around the Antarctic may be related both to adjacent shelf communities and to those in other oceans. Unlike shallow-water Antarctic benthic communities, however, little is known about life in this vast deep-sea region. Here, we report new data from recent sampling expeditions in the deep Weddell Sea and adjacent areas (748-6,348 m water depth) that reveal high levels of new biodiversity; for example, 674 isopods species, of which 585 were new to science. Bathymetric and biogeographic trends varied between taxa. In groups such as the isopods and polychaetes, slope assemblages included species that have invaded from the shelf. In other taxa, the shelf and slope assemblages were more distinct. Abyssal faunas tended to have stronger links to other oceans, particularly the Atlantic, but mainly in taxa with good dispersal capabilities, such as the Foraminifera. The isopods, ostracods and nematodes, which are poor dispersers, include many species currently known only from the Southern Ocean. Our findings challenge suggestions that deep-sea diversity is depressed in the Southern Ocean and provide a basis for exploring the evolutionary significance of the varied biogeographic patterns observed in this remote environment. 相似文献