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排序方式: 共有412条查询结果,搜索用时 19 毫秒
101.
Hubert B Wicker B Moore DG Monfardini E Duverger H Da Fonséca D Deruelle C 《Journal of autism and developmental disorders》2007,37(7):1386-1392
This study aimed to explore the perception of different components of biological movement in individuals with autism and Asperger syndrome. The ability to recognize a person's actions, subjective states, emotions, and objects conveyed by moving point-light displays was assessed in 19 participants with autism and 19 comparable typical control participants. Results showed that the participants with autism were as able as controls to name point-light displays of non-human objects and human actions. In contrast, they were significantly poorer at labeling emotional displays, suggesting that they are specifically impaired in attending to emotional states. Most studies have highlighted an emotional deficit in facial expression perception; our results extend this hypothesized deficit to the perception and interpretation of whole-body biological movements. 相似文献
102.
103.
Cytogenetic map of common bean (Phaseolus vulgaris L.) 总被引:1,自引:0,他引:1
Artur Fonsêca Joana Ferreira Tiago Ribeiro Barros dos Santos Magdalena Mosiolek Elisa Bellucci James Kami Paul Gepts Valérie Geffroy Dieter Schweizer Karla G. B. dos Santos Andrea Pedrosa-Harand 《Chromosome research》2010,18(4):487-502
A cytogenetic map of common bean was built by in situ hybridization of 35 bacterial artificial chromosomes (BACs) selected with markers mapping to eight linkage groups, plus two plasmids for 5S and 45S ribosomal DNA and one bacteriophage. Together with three previously mapped chromosomes (chromosomes 3, 4, and 7), 43 anchoring points between the genetic map and the cytogenetic map of the species are now available. Furthermore, a subset of four BAC clones was proposed to identify the 11 chromosome pairs of the standard cultivar BAT93. Three of these BACs labelled more than a single chromosome pair, indicating the presence of repetitive DNA in their inserts. A repetitive distribution pattern was observed for most of the BACs; for 38% of them, highly repetitive pericentromeric or subtelomeric signals were observed. These distribution patterns corresponded to pericentromeric and subtelomeric heterochromatin blocks observed with other staining methods. Altogether, the results indicate that around half of the common bean genome is heterochromatic and that genes and repetitive sequences are intermingled in the euchromatin and heterochromatin of the species. 相似文献
104.
105.
P J van Horssen Y V van Oosterhout S Evers H H Backus M G van Oijen R Bongaerts T de Witte F W Preijers 《Leukemia》1999,13(2):241-249
Despite the strong in vitro activity of some immunotoxins (ITs), clinical application did not result in complete cure. The outcome of therapy may be improved by combining ITs with IT-cytotoxicity enhancing agents. We studied the effect of various agents that influence the intracellular routing of ITs on the activity of the anti-B cell IT CD22-recombinant (rec) ricin A. In protein synthesis inhibition assays the carboxylic ionophores monensin and nigericin enhanced the activity of the IT 117- and 382-fold, respectively, against the cell line Daudi, and 81- and 318-fold, respectively, against the cell line Ramos. IT activity to Daudi and Ramos was enhanced to a lesser extent by the lysosomotropic amines chloroquine (14- and 11-fold, respectively) and NH4Cl (nine- and 10-fold, respectively). However, the combination of NH4Cl and chloroquine induced more than an additive effect (145- and 107-fold, respectively). Cytotoxicity was not influenced by brefeldin A, all-trans retinoic acid (ATRA), verapamil and perhexiline maleate. Bacitracin enhanced the IT cytotoxicity in contrast to the other protease inhibitors aprotinin, leupeptin and soybean trypsin inhibitor, albeit enhancement was weak (two-fold). The enhancers exerted only a negligible effect on bone marrow progenitor cells. We recently developed a flow cytometric cytotoxicity assay in which cell elimination can be assessed. In order to detect enhancement in this assay, we used 5 x 10(-11) M IT (approximately the 50% protein synthesis inhibiting dose (ID50)). This concentration killed 41% of the Daudi cells and 42% of the Ramos cells. In the presence of 10 nM monensin the IT killed 74% and 99% and in the presence of 10 nM nigericin 96% and 99% of the Daudi and Ramos cells, respectively. At 10(-8) M, CD22-rec ricin A eliminated malignant cells originating from three patients with B-CLL (0.42 log) and two with B-ALL (0.19 log) patients. Cytotoxicity to malignant cells was enhanced by NH4Cl, chloroquine, monensin and nigericin. The combination of NH4Cl and chloroquine enhanced the activity most effectively (up to 2.06 log). To determine the applicability of the IT in combination with enhancers in vivo we investigated the effect of human serum. Human serum inhibited IT activity which could not be restored by monensin and nigericin because of complete inhibition of these enhancers by serum. In contrast, chloroquine partially restored the activity of CD22-rec ricin A in the presence of human serum. We conclude that monensin, nigericin and the combination of NH4Cl and chloroquine can be used instead of NH4Cl to potentiate CD22-rec ricin A activity in purging autologous bone marrow transplants contaminated with malignant B cells. Chloroquine might be a promising enhancer of CD22-rec ricin A for treating patients in vivo. 相似文献
106.
Elstrodt F Hollestelle A Nagel JH Gorin M Wasielewski M van den Ouweland A Merajver SD Ethier SP Schutte M 《Cancer research》2006,66(1):41-45
Germ line mutations of the BRCA1 gene confer a high risk of breast cancer and ovarian cancer to female mutation carriers. The BRCA1 protein is involved in the regulation of DNA repair. How specific tumor-associated mutations affect the molecular function of BRCA1, however, awaits further elucidation. Cell lines that harbor BRCA1 gene mutations are invaluable tools for such functional studies. Up to now, the HCC1937 cell line was the only human breast cancer cell line with an identified BRCA1 mutation. In this study, we identified three other BRCA1 mutants from among 41 human breast cancer cell lines by sequencing of the complete coding sequence of BRCA1. Cell line MDA-MB-436 had the 5396 + 1G>A mutation in the splice donor site of exon 20. Cell line SUM149PT carried the 2288delT mutation and SUM1315MO2 carried the 185delAG mutation. All three mutations were accompanied by loss of the other BRCA1 allele. The 185delAG and 5396 + 1G>A mutations are both classified as pathogenic mutations. In contrast with wild-type cell lines, none of the BRCA1 mutants expressed nuclear BRCA1 proteins as detected with Ab-1 and Ab-2 anti-BRCA1 monoclonal antibodies. These three new human BRCA1 mutant cell lines thus seem to be representative breast cancer models that could aid in further unraveling of the function of BRCA1. 相似文献
107.
Oesophageal endoscopic ultrasound with fine needle aspiration improves and simplifies the staging of lung cancer 下载免费PDF全文
Kramer H van Putten JW Post WJ van Dullemen HM Bongaerts AH Pruim J Suurmeijer AJ Klinkenberg TJ Groen H Groen HJ 《Thorax》2004,59(7):596-601
BACKGROUND: Positron emission tomography (PET) is accurate for mediastinal staging of lung cancer but has a moderate positive predictive value, necessitating pathological verification. Endoscopic ultrasonography with fine needle aspiration (EUS-FNA) is a technique for tissue verification of mediastinal and upper retroperitoneal abnormalities. The use of EUS-FNA may decrease the number of surgical procedures and thereby staging costs. METHODS: EUS-FNA was used prospectively for the cytological assessment of mediastinal and/or upper retroperitoneal PET hot spots in patients with suspected lung cancer. Only if EUS-FNA was positive for malignancy was subsequent mediastinoscopy or exploratory thoracotomy cancelled. The cost effectiveness of EUS-FNA was determined. RESULTS: Of 488 consecutive patients with suspected lung cancer, 81 were enrolled with mediastinal and/or upper retroperitoneal PET hot spots. EUS-FNA was positive in 50 (62%) patients, negative in six, and inconclusive in 25. Of the 31 negative or inconclusive patients, 26 underwent surgical staging (resulting in 14 patients with and 12 without mediastinal malignancy), while five patients had mediastinal metastases during follow up. No EUS-FNA related morbidity or mortality was encountered. The accuracy of the decision to proceed to surgery (or not) on the basis of EUS-FNA was 77% (95% CI 68 to 86). EUS-FNA detected more mediastinal abnormalities than PET except for the upper mediastinal region. Addition of EUS-FNA to conventional lung cancer staging reduced staging costs by 40% per patient, mainly due to a decrease in surgical staging procedures. CONCLUSION: EUS-FNA can replace more than half of the surgical staging procedures in lung cancer patients with mediastinal and/or upper retroperitoneal PET hot spots, thereby saving 40% of staging costs. 相似文献
108.
The aim of this study was to investigate the in vitro beta-lactam-induced response of clinical Gram-negative bacteria with the potential for inducible beta-lactamase production, in order to be able to discriminate diagnostically between inducible and constitutive beta-lactamase production. A total of 242 clinical Gram-negative isolates of species with inducible chromosomal beta-lactamase were subjected to a disc diffusion test involving agar dilution of the inducers. Cefoxitin (FOX) and imipenem (IPM) were used as inducers and the antibiotics ceftazidime, cefuroxim, cefazolin, amoxycillin and piperacillin as indicators. beta-lactamase induction was observed at concentrations as low as 0.06 mg/l FOX or 0.008 mg/l IPM. In our test, 2 types of antibiotic phenomenon often interfered with inductive effects. Firstly a minor antibiotic effect was seen as an increase in inhibition zones at increasing inducer concentration and, secondly, absence of growth was caused by too high antibiotic activity of the inducer. The induced decrease in zone diameters varied strongly (up to 22 mm). Expressions of resistance were combined in inducibility profiles. Compilation of these profiles allowed an explanation to be proposed for the multi(-beta-lactam)-resistance, i.e. that most isolates combine inducible beta-lactamase synthesis with one or more resistance-potentiating factors. Only a few isolates demonstrated non-inducible resistance, which was probably due to mutation-mediated de-repression of beta-lactamase synthesis. The test presented here may be well-suited to studying inducibility of beta-lactamase production in the diagnostic laboratory. 相似文献
109.
Judith Potashkin Daemyung Kim Mark Fons Tim Humphrey David Frendewey 《Current genetics》1998,34(3):153-163
We have isolated six new pre-mRNA splicing mutants (prp) from a collection of temperature-sensitive (ts–) Schizosaccharomyces pombe strains. The prp mutants are defective in the splicing of both messenger RNA and U6 small nuclear RNA precursors. A single recessive mutation
is responsible for both the ts
–
growth and the splicing phenotypes in each of the prp mutants. The six prp mutations are unlinked and fall into separate complementation groups. Two are allelic with the previously described prp3 and prp4 mutations; the remaining four define the new alleles prp5-1, prp6-1, prp7-1, and prp9-1. The six mutants exhibit three splicing phenotypes: accumulation of unspliced precursor at the restrictive but not at the
permissive temperature; accumulation of unspliced precursor at both the permissive and restrictive temperatures; and accumulation
of unspliced precursor, the intron-exon lariat intermediate, and the intron lariat final product. In addition to their aberrant
splicing phenotypes, the prp5-1 and prp6-1 mutants express classical cell-division-cycle defects, while prp7-1 exhibits an unusual hyphal morphology. These results suggest a connection between pre-mRNA splicing and the control of cell
division in fission yeast.
Received: 1 June / 10 July 1998 相似文献
110.
Albrecht T Deng CZ Abdel-Rahman SZ Fons M Cinciripini P El-Zein RA 《Environmental and molecular mutagenesis》2004,43(3):169-178
We used the mutagen sensitivity assay to test the hypothesis that human cytomegalovirus (HCMV) infection modifies the sensitivity of cells to genetic damage from genotoxic agents. Chromosome aberration (CA) frequency in peripheral blood lymphocytes (PBLs) from 20 smokers who were matched with 20 nonsmokers by age (+/- 5 years), sex, and ethnicity was evaluated following in vitro exposure to bleomycin and/or HCMV infection. Bleomycin induced significant (P < 0.05) concentration-dependent increases in the frequency of aberrant cells, chromatid-type damage (breaks), and chromosome-type aberrations (deletions, rearrangements) in PBLs. The baseline (background) CA frequency was similar in both smokers and nonsmokers. Significantly higher frequencies of aberrant cells (P < 0.05) were observed in PBLs from smokers compared to nonsmokers at all bleomycin concentrations tested (10, 30 and 100 microg/ml). Infection of PBLs with HCMV induced a significant (P < 0.05) twofold increase in the frequency of CA (primarily chromatid breaks) in PBLs, regardless of the smoking status. PBLs from smokers and nonsmokers infected with HCMV prior to challenge with bleomycin demonstrated significant (P < 0.05) concentration-dependent increases in the levels of aberrant cells, chromatid-type damage (breaks), and chromosome-type aberrations (deletions, rearrangements) compared to noninfected cells challenged with bleomycin. The frequency of induced CA was consistently higher for PBLs derived from smokers relative to nonsmokers (P = 0.06 and 0.002). These data indicate that, individually, both smoking and HCMV infection significantly enhance the sensitivity of PBLs to bleomycin-induced genetic damage. More importantly, the data also suggest that smoking and HCMV infection interact synergistically to enhance the sensitivity of PBLs to such damage. 相似文献