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排序方式: 共有274条查询结果,搜索用时 20 毫秒
91.
Chatel G Desai SH Mattheyses AL Powers MA Fahrenkrog B 《Journal of structural biology》2012,177(1):81-89
Nuclear pore complexes (NPCs) facilitate selective transport of macromolecules across the nuclear envelope in interphase eukaryotic cells. NPCs are composed of roughly 30 different proteins (nucleoporins) of which about one third are characterized by the presence of phenylalanine-glycine (FG) repeat domains that allow the association of soluble nuclear transport receptors with the NPC. Two types of FG (FG/FxFG and FG/GLFG) domains are found in nucleoporins and Nup98 is the sole vertebrate nucleoporin harboring the GLFG-type repeats. By immuno-electron microscopy using isolated nuclei from Xenopus oocytes we show here the localization of distinct domains of Nup98. We examined the localization of the C- and N-terminal domain of Nup98 by immunogold-labeling using domain-specific antibodies against Nup98 and by expressing epitope tagged versions of Nup98. Our studies revealed that anchorage of Nup98 to NPCs through its C-terminal autoproteolytic domain occurs in the center of the NPC, whereas its N-terminal GLFG domain is more flexible and is detected at multiple locations within the NPC. Additionally, we have confirmed the central localization of Nup98 within the NPC using super resolution structured illumination fluorescence microscopy (SIM) to position Nup98 domains relative to markers of cytoplasmic filaments and the nuclear basket. Our data support the notion that Nup98 is a major determinant of the permeability barrier of NPCs. 相似文献
92.
ME Beutel M Leuzinger-Bohleber B Rüger U Bahrke A Negele A Haselbacher G Fiedler W Keller M Hautzinger 《Trials》2012,13(1):117
ABSTRACT: BACKGROUND: Despite limited effectiveness of short-term psychotherapy for chronic depression, there is a lack of trials of long-term psychotherapy. Our study is the first to determine the effectiveness of controlled long-term psychodynamic and cognitive-behavioral (CBT) treatments and to assess the effects of preferential vs. randomized assessment. Methods / Design: Patients are assigned to treatment according to their preference or randomized (if they have no clear preference). Up to 80 sessions of psychodynamic or psychoanalytically oriented treatments (PAT) or up to 45 sessions of CBT are offered during the first year in the study. After the first year, PAT can be continued according to the "naturalistic", usual way of treating such patients within the system of German health care system (normally 240 up to 300 sessions), CBT therapists may extend their treatment up to 80 sessions, but focus mainly on maintenance and relapse prevention. We plan to recruit a total of 240 patients (60 per arm). A total of 11 assessments are conducted throughout treatment and up to 3 years after initiation of treatment. The primary outcome measures are the QIDS (independent clinician rating) and the BDI after year 1, 2 and 3. DISCUSSION: We combine an RCT and a naturalistic approach in order to investigate, how effectively chronic depression can be treated on an outpatient basis by the two forms of treatment reimbursed in the German health care system and we will determine the effects of treatment preference vs. randomization. 相似文献
93.
Jakse J Telgmann A Jung C Khar A Melgar S Cheung F Town CD Havey MJ 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2006,114(1):31-39
The Poales (includes the grasses) and Asparagales [includes onion (Allium cepa L.) and asparagus (Asparagus officinalis L.)] are the two most economically important monocot orders. The Poales are a member of the commelinoid monocots, a group of orders sister to the Asparagales. Comparative genomic analyses have revealed a high degree of synteny among the grasses; however, it is not known if this synteny extends to other major monocot groups such as the Asparagales. Although we previously reported no evidence for synteny at the recombinational level between onion and rice, microsynteny may exist across shorter genomic regions in the grasses and Asparagales. We sequenced nine asparagus BACs to reveal physically linked genic-like sequences and determined their most similar positions in the onion and rice genomes. Four of the asparagus BACs were selected using molecular markers tightly linked to the sex-determining M locus on chromosome 5 of asparagus. These BACs possessed only two putative coding regions and had long tracts of degenerated retroviral elements and transposons. Five asparagus BACs were selected after hybridization of three onion cDNAs that mapped to three different onion chromosomes. Genic-like sequences that were physically linked on the cDNA-selected BACs or genetically linked on the M-linked BACs showed significant similarities (e < −20) to expressed sequences on different rice chromosomes, revealing no evidence for microsynteny between asparagus and rice across these regions. Genic-like sequences that were linked in asparagus were used to identify highly similar (e < −20) expressed sequence tags (ESTs) of onion. These onion ESTs mapped to different onion chromosomes and no relationship was observed between physical or genetic linkages in asparagus and genetic linkages in onion. These results further indicate that synteny among grass genomes does not extend to a sister order in the monocots and that asparagus may not be an appropriate smaller genome model for plants in the Asparagales with enormous nuclear genomes. 相似文献
94.
95.
Berger R Zhu C Hansen AR Harper B Chen Z Holt TG Hubert J Lee SJ Pan J Qian S Reitman ML Strack AM Weingarth DT Wolff M Macneil DJ Weber AE Edmondson SD 《Bioorganic & medicinal chemistry letters》2008,18(17):4833-4837
The discovery and structure–activity relationship of 1,2-diarylimidazole piperazine carboxamides bearing polar side chains as potent and selective cholecystokinin 1 receptor (CCK1R) agonists are described. Optimization of this series resulted in the discovery of isopropyl carboxamide 40, a CCK1R agonist with sub-nanomolar functional and binding activity as well as excellent potency in a mouse overnight food intake reduction assay. 相似文献
96.
Zhu C Hansen AR Bateman T Chen Z Holt TG Hubert JA Karanam BV Lee SJ Pan J Qian S Reddy VB Reitman ML Strack AM Tong V Weingarth DT Wolff MS MacNeil DJ Weber AE Duffy JL Edmondson SD 《Bioorganic & medicinal chemistry letters》2008,18(15):4393-4396
High-throughput screening revealed diaryl pyrazole 3 as a selective albeit modest cholecystokinin 1 receptor (CCK1R) agonist. SAR studies led to the discovery and optimization of a novel class of 1,2-diaryl imidazole carboxamides. Compound 44, which was profiled extensively, showed good in vivo mouse gallbladder emptying (mGBE) and lean mouse overnight food intake (ONFI) reduction activities. 相似文献
97.
Bogojeska J Alexa A Altmann A Lengauer T Rahnenführer J 《Bioinformatics (Oxford, England)》2008,24(20):2391-2392
In genetics, many evolutionary pathways can be modeled by the ordered accumulation of permanent changes. Mixture models of mutagenetic trees have been used to describe disease progression in cancer and in HIV. In cancer, progression is modeled by the accumulation of chromosomal gains and losses in tumor cells; in HIV, the accumulation of drug resistance-associated mutations in the viral genome is known to be associated with disease progression. From such evolutionary models, genetic progression scores can be derived that assign measures for the disease state to single patients. Rtreemix is an R package for estimating mixture models of evolutionary pathways from observed cross-sectional data and for estimating associated genetic progression scores. The package also provides extended functionality for estimating confidence intervals for estimated model parameters and for evaluating the stability of the estimated evolutionary mixture models. 相似文献
98.
Saoussen Trabelsi Imen Chabchoub Iadh Ksira Nadhir Karmeni Nadia Mama Samia Kanoun Anna Burford Alexa Jury Alan Mackay Sergey Popov Noureddine Bouaouina Slim Ben Ahmed Moncef Mokni Kalthoum Tlili Hedi Krifa Mohamed Tahar Yacoubi Chris Jones Ali Saad Dorra H’mida Ben Brahim 《Molecular neurobiology》2017,54(4):2381-2394
It has become increasingly evident that morphologically similar gliomas may have distinct clinical phenotypes arising from diverse genetic signatures. To date, glial tumours from the Tunisian population have not been investigated. To address this, we correlated the clinico-pathology with molecular data of 110 gliomas by a combination of HM450K array, MLPA and TMA-IHC. PTEN loss and EGFR amplification were distributed in different glioma histological groups. However, 1p19q co-deletion and KIAA1549:BRAF fusion were, respectively, restricted to Oligodendroglioma and Pilocytic Astrocytoma. CDKN2A loss and EGFR overexpression were more common within high-grade gliomas. Furthermore, survival statistical correlations led us to identify Glioblastoma (GB) prognosis subtypes. In fact, significant lower overall survival (OS) was detected within GB that overexpressed EGFR and Cox2. In addition, IDH1R132H mutation seemed to provide a markedly survival advantage. Interestingly, the association of IDHR132H mutation and EGFR normal status, as well as the association of differentiation markers, defined GB subtypes with good prognosis. By contrast, poor survival GB subtypes were defined by the combination of PTEN loss with PDGFRa expression and/or EGFR amplification. Additionally, GB presenting p53-negative staining associated with CDKN2A loss or p21 positivity represented a subtype with short survival. Thus, distinct molecular subtypes with individualised prognosis were identified. Interestingly, we found a unique histone mutation in a poor survival young adult GB case. This tumour exceptionally associated the H3F3A G34R mutation and MYCN amplification as well as 1p36 loss and 10q loss. Furthermore, by exhibiting a remarkable methylation profile, it emphasised the oncogenic power of G34R mutation connecting gliomagenesis and chromatin regulation. 相似文献
99.
Robert J. Full Alexa Tullis 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1990,160(5):573-581
Summary The capacity for sustained, terrestrial locomotion in the cockroach. Blaberus discoidalis, was determined in relation to running speed, metabolic cost, aerobic capacity, and ambient temperature (T
a=15, 23, and 34°C; acclimation temperature=24°C). Steady-state thoracic temperature (T
tss) increased linearly with speed at each T
a.The difference between T
tss and T
awas similar at each experimental temperature with a maximum increase of 7°C. Steady-state oxygen consumption (VO2ss) increased linearly with speed at each T
aand had a low thermal dependence (Q10=1.0-1.4). The minimum cost of locomotion (the slope of the VO2ss versus speed function) was independent of T
a.Cockroaches attained a maximal oxygen consumption (VO2max). increased with T
afrom 2.1 ml O2·g-1·h-1 at 15°C to 4.9 ml O2·g-1·h-1 at 23°C, but showed no further increase at 34°C, VO2max increased 23-fold over resting VO2 at 23°C, 10-fold at 34°C, and 15-fold at 15°C. Endurance correlated with the speed at which VO2max was attained (MAS, maximal aerobic speed). Temperature affected the kinematics of locomotion. compared to cockroaches running at the same speed, but higher temperatures (23–34°C), low temperature (15°C) increased protraction time, reduced stride frequency, and reduced stability by increasing body pitching. The thermal independence of the minimum cost of locomotion (Cmin), the low thermal dependence of VO2ss (i.e., y-intercept of the VO2ss versus speed function), and a typical Q10 of 2.0 for VO2max combined to increase MAS and endurance in B. discoidalis when T
awas increased from 15 to 23°C. Exerciserelated endothermy enabled running cockroaches to attain a greater VO2max, metabolic scope, and endurance capacity at 23°C than would be possible if T
tss remained equal to T
a. The MAS of B. discoidalis was similar to that of other arthropods that use trachea, but was 2-fold greater than ectotherms, such as salamanders, frogs, and crabs of a comparable body mass.Abbreviations
T
a
ambient temperature
-
T
t
thoracic temperature
-
T
tss
steady state thoracic temperature during exercise
-
T
trest
thoracic temperature during rest
- VO2
oxygen consumption
- VO2rest
oxygen consumption during rest
- VO2ss
steady-state oxygen consumption during exercise
- VO2max
maximal oxygen consumption; MAS maximum aerobic speed
-
C
min
minimum cost of locomotion
-
t
end
endurance time 相似文献
100.
Hancock K Zajac AM Pung OJ Elvinger F Rosypal AC Lindsay DS 《The Journal of parasitology》2005,91(2):470-472
Raccoons (Procyon lotor) are reservoir hosts for Trypanosoma cruzi. A 3-yr-long serological survey was conducted to determine the prevalence of antibodies to this zoonotic parasite in raccoons collected from Fairfax County, Virginia, a suburban/urban area outside Washington, D.C. Serum samples from 464 raccoons were examined for T. cruzi antibodies at a 1:40 dilution with an indirect fluorescent antibody test (IFAT) and Brazil strain T. cruzi amastigotes and trypomastigotes as antigen. A positive IFAT test was found in 154 (33%) of the 464 samples. The yearly prevalence was 49 of 132 (37%) in 2000; 19 of 120 (16%) in 2001; and 86 of 212 (41%) in 2002. Our study indicates that raccoons in this area of Virginia are frequently exposed to T. cruzi. 相似文献