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排序方式: 共有1933条查询结果,搜索用时 15 毫秒
61.
Qualls Lydia R. Hartmann Kathrin Paulson James F. Wells Nicole Kreiser 《Journal of autism and developmental disorders》2022,52(4):1678-1692
Journal of Autism and Developmental Disorders - Individuals with Autism Spectrum Disorder (ASD) and the Broad Autism Phenotype (BAP) are more likely than individuals with typical development (TD)... 相似文献
62.
The hemagglutinins of influenza viruses isolated from humans typically prefer binding to sialic acid in an alpha2,6 linkage. Presumably, the virus uses the presence of these receptors on the respiratory tract to gain entrance into the host cell. The ST6Gal I sialyltransferase knock-out mouse lacks the main enzyme necessary for the attachment of alpha2,6 sialic acid to N-linked glycoproteins on the cell surface. Yet even in the absence of detectable alpha2,6 sialic acid in the mouse respiratory tract, human influenza viruses can still infect these mice and grow to similar titers in the lung and trachea as compared to wild-type animals. This work demonstrates that the presence of a major alpha2,6 sialic acid on N-linked glycoproteins is not essential for human influenza virus infection in mice. 相似文献
63.
Plasma levels of plasminogen activator inhibitor type-1 (PAI-1), beta- thromboglobulin (beta TG), and fibrinopeptide A (FPA) were followed over 24 hours in 30 patients treated with alteplase for acute myocardial infarction. Samples were taken at baseline (T Oh), after 90 minutes (under alteplase, no heparin, T 1.5h), after 120 minutes (under alteplase and heparin, T 2h), 30 minutes after thrombolytic therapy (T 3.5h), as well as 12 hours (T 12h) and 24 hours (T 24h) after baseline. PAI-1 antigen levels (55 +/- 9 ng/mL at T Oh, mean +/- SEM) decreased to 35 +/- 5 (T 1.5h) and 40 +/- 6 (T 2h) ng/mL under alteplase, before increasing to 84 +/- 22 (T 3.5h), 130 +/- 30 (T 12h), and 64 +/- 7 (T 24h) ng/mL after therapy, P less than .001. A high baseline PAI-1 activity (18 +/- 3 ng/mL) decreased to 2.0 +/- 0.4 (T 1.5h) and 1.7 +/- 0.2 (T 2h) under alteplase and increased to 32 +/- 5 (T 12h) and 19 +/- 3 (T 24h) ng/mL after therapy (P less than .0001). beta TG levels (339 +/- 105 ng/mL at T Oh) decreased to 203 +/- 48 (T 2h), 154 +/- 51 (T 3.5h), 187 +/- 40 (T 12h), and 142 +/- 32 (T 24h) ng/mL under heparin (P less than .01). FPA levels (34 +/- 9 ng/mL at T Oh) increased to 85 +/- 15 ng/mL under alteplase alone (T 1.5h) and normalized under heparin (11 +/- 4, 6 +/- 2, 4 +/- 2, and 3 +/- 1 ng/mL at T 2h, T 3.5h, T 12h, and T 24h, respectively). A high level of FPA at T 3.5h correlated with reocclusion (33 +/- 12 ng/mL, n = 4 v 2.9 +/- 0.5 ng/mL, n = 21, P less than .005). We conclude that plasma levels of PAI- 1 antigen as well as activity markedly increase after alteplase therapy of acute myocardial infarction. The high activity of PAI-1 and decreasing beta TG levels suggest that platelets do not contribute significantly to this phenomenon. The marked increase of FPA levels under recombinant tissue-type plasminogen activator alone and its normalization under heparin emphasize the important role of concomitant anticoagulation in controlling further intravasal fibrin generation under alteplase. 相似文献
64.
Oncogenic mutation in the Kit receptor tyrosine kinase alters
substrate specificity and induces degradation of the protein
tyrosine phosphatase SHP-1 下载免费PDF全文
Xianhua Piao Robert Paulson Peter vanderGeer Tony Pawson Alan Bernstein 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(25):14665-14669
Activating mutations in the Kit receptor tyrosine kinase have been identified in both rodent and human mast cell leukemia. One activating Kit mutation substitutes a valine for aspartic acid at codon 816 (D816V) and is frequently observed in human mastocytosis. Mutation at the equivalent position in the murine c-kit gene, involving a substitution of tyrosine for aspartic acid (D814Y), has been described in the mouse mastocytoma cell line P815. We have investigated the mechanism of oncogenic activation by this mutation. Expression of this mutant Kit receptor tyrosine kinase in a mast cell line led to the selective tyrosine phosphorylation of a 130-kDa protein and the degradation, through the ubiquitin-dependent proteolytic pathway, of a 65-kDa phosphoprotein. The 65-kDa protein was identified as the src homology domain 2 (SH2)-containing protein tyrosine phosphatase SHP-1, a negative regulator of signaling by Kit and other hematopoietic receptors, and the protein product of the murine motheaten locus. This mutation also altered the sites of receptor autophosphorylation and peptide substrate selectivity. Thus, this mutation activates the oncogenic potential of Kit by a novel mechanism involving an alteration in Kit substrate recognition and the degradation of SHP-1, an attenuator of the Kit signaling pathway. 相似文献
65.
Lisa R. Miller‐Matero Anne Eshelman Daniel Paulson Rachel Armstrong Kimberly A. Brown Dilip Moonka Marwan Abouljoud 《Clinical transplantation》2014,28(6):691-698
To help decrease mortality on the liver transplant waitlist, transplant centers are using living donors (LD) and high‐risk donors (HRD) in addition to standard‐risk donors (SRD). HRD is defined as having a donor risk index score higher than 1.6, which suggests a great risk of graft failure. Recent studies have examined survival rates between HRD and SRD recipients; however, little is known about outcomes other than survival, specifically psychosocial outcomes. The purpose of this preliminary, prospective study was to compare post‐transplant psychosocial and recovery outcomes between SRD and LD and HRD liver recipients. These outcomes include cognitive functioning, psychological distress, quality of life, and self‐reported and objective measures of recovery. Eighty‐four patients provided baseline and six‐month post‐transplant data. There were generally no statistically significant differences at baseline or the six‐month follow‐up, suggesting that patients receiving HRD livers have similar outcomes to those who receive SRD livers. However, some effect sizes suggest potential advantages for LD recipients compared to SRD recipients. Transplant centers may be more willing to encourage patients to accept HRD or LD livers knowing that they may have comparable outcomes to SRD recipients, which also has implications for the transplant waitlist. 相似文献
66.
Victoria L. Goosey-Tolfrey Thomas A. W. Paulson Keith Tolfrey Roger G. Eston 《European journal of applied physiology》2014,114(6):1251-1258
Purpose
To assess the validity of predicting peak oxygen uptake ( $ {\dot{\text{V}}}{\text{O}}_{{\text{2peak}}}$ ) from differentiated ratings of perceived exertion (RPE) obtained during submaximal wheelchair propulsion.Methods
Three subgroups of elite male wheelchair athletes [nine tetraplegics (TETRA), nine paraplegics (PARA), eight athletes without spinal cord injury (NON-SCI)] performed an incremental speed exercise test followed by graded exercise to exhaustion ( $ {\dot{\text{V}}}{\text{O}}_{{\text{2peak}}}$ test). Oxygen uptake ( $ {\dot{\text{V}}}{\text{O}}_2$ ), heart rate (HR) and differentiated RPE (Central RPEC, Peripheral RPEP and Overall RPEO) were obtained for each stage. The regression lines for the perceptual ranges 9–15 on the Borg 6–20 scale ratings were performed to predict $ {\dot{\text{V}}}{\text{O}}_{{\text{2peak}}}$ .Results
There were no significant within-group mean differences between measured $ {\dot{\text{V}}}{\text{O}}_{{\text{2peak}}}$ (mean 1.50 ± 0.39, 2.74 ± 0.48, 3.75 ± 0.33 L min?1 for TETRA, PARA and NON-SCI, respectively) and predicted $ {\dot{\text{V}}}{\text{O}}_{{\text{2peak}}}$ determined using HR or differentiated RPEs for any group (P > 0.05). However, the coefficients of variation (CV %) between measured and predicted $ {\dot{\text{V}}}{\text{O}}_{{\text{2peak}}}$ using HR showed high variability for all groups (14.3, 15.9 and 9.7 %, respectively). The typical error ranged from 0.14 to 0.68 L min?1 and the CV % between measured and predicted $ {\dot{\text{V}}}{\text{O}}_{{\text{2peak}}}$ using differentiated RPE was ≤11.1 % for TETRA, ≤7.5 % for PARA and ≤20.2 % for NON-SCI.Conclusions
Results suggest that differentiated RPE may be used cautiously for TETRA and PARA athletes when predicting $ {\dot{\text{V}}}{\text{O}}_{{\text{2peak}}}$ across the perceptual range of 9–15. However, predicting $ {\dot{\text{V}}}{\text{O}}_{{\text{2peak}}}$ is not recommended for the NON-SCI athletes due to the large CV %s (16.8, 20.2 and 18.0 %; RPEC, RPEP and RPEO, respectively). 相似文献67.
Akihiro Takamiya Annemiek Dols Louise Emsell Christopher Abbott Antoine Yrondi Carles Soriano Mas Martin Balslev Jorgensen Pia Nordanskog Didi Rhebergen Eric van Exel Mardien L Oudega Filip Bouckaert Mathieu Vandenbulcke Pascal Sienaert Patrice Pran Marta Cano Narcis Cardoner Anders Jorgensen Olaf B Paulson Paul Hamilton Robin Kampe Willem Bruin Hauke Bartsch Olga Therese Ousdal Ute Kessler Guido van Wingen Leif Oltedal Taishiro Kishimoto 《Schizophrenia bulletin》2022,48(2):514
Psychotic major depression (PMD) is hypothesized to be a distinct clinical entity from nonpsychotic major depression (NPMD). However, neurobiological evidence supporting this notion is scarce. The aim of this study is to identify gray matter volume (GMV) differences between PMD and NPMD and their longitudinal change following electroconvulsive therapy (ECT). Structural magnetic resonance imaging (MRI) data from 8 independent sites in the Global ECT-MRI Research Collaboration (GEMRIC) database (n = 108; 56 PMD and 52 NPMD; mean age 71.7 in PMD and 70.2 in NPMD) were analyzed. All participants underwent MRI before and after ECT. First, cross-sectional whole-brain voxel-wise GMV comparisons between PMD and NPMD were conducted at both time points. Second, in a flexible factorial model, a main effect of time and a group-by-time interaction were examined to identify longitudinal effects of ECT on GMV and longitudinal differential effects of ECT between PMD and NPMD, respectively. Compared with NPMD, PMD showed lower GMV in the prefrontal, temporal and parietal cortex before ECT; PMD showed lower GMV in the medial prefrontal cortex (MPFC) after ECT. Although there was a significant main effect of time on GMV in several brain regions in both PMD and NPMD, there was no significant group-by-time interaction. Lower GMV in the MPFC was consistently identified in PMD, suggesting this may be a trait-like neural substrate of PMD. Longitudinal effect of ECT on GMV may not explain superior ECT response in PMD, and further investigation is needed. 相似文献
68.
Imaging-guided percutaneous biopsy of focal splenic lesions: update on safety and effectiveness 总被引:5,自引:0,他引:5
Keogan MT Freed KS Paulson EK Nelson RC Dodd LG 《AJR. American journal of roentgenology》1999,172(4):933-937
OBJECTIVE: The purpose of this study is to determine the safety and effectiveness of percutaneous imaging-guided biopsy in the diagnosis of focal splenic lesions. MATERIALS AND METHODS: From May 1995 to November 1997, 20 imaging-guided biopsies of focal splenic lesions were performed in 18 patients, including seven patients with a prior diagnosis of extrasplenic malignancy (breast cancer, n = 3; lymphoma, n = 2; ovarian cancer, n = 1; and osteogenic sarcoma, n = 1), three immunosuppressed patients (cause of immunosuppression: AIDS, n = 1; liver transplantation, n = 1; and bone marrow transplantation, n = 1), two patients with anemia, one patient with a recent history of IV drug abuse, and five patients with incidentally discovered splenic lesions. Biopsies were performed with an 18-gauge (n = 1), a 20-gauge (n = 8), or a 22-gauge (n = 14) self-aspirating needle or an 18-gauge cutting needle (n = 1). Biopsies were considered successful if a specific diagnosis of benign or malignant disease was made. RESULTS: A specific diagnosis was made in 16 (88.9%) of 18 patients, and no complications occurred. Malignancy was diagnosed in six patients including three patients with lymphoma. Benign conditions were diagnosed in 10 patients: a cyst in two patients; hamartoma in one; lipogranuloma in one; infarct in one; and infection in four, including one case each of Candida albicans, Pneumocystis carinii, Mycobacterium tuberculosis, and mixed flora. The tenth benign diagnosis was a pseudotumor of the spleen related to a bulbous tail of the pancreas that was inseparable from the splenic hilum. Biopsy did not establish a diagnosis in one patient with lymphoma and in one patient with presumed splenic candidiasis. A mean of 1.5 needle passes was made per biopsy. CONCLUSION: Imaging-guided splenic biopsy is a safe technique that provides a specific diagnosis in most patients with focal splenic lesions. 相似文献
69.
The purpose of the present study was to examine the outcome profiles of a large number of patients with locally advanced
adenocarcinoma of the prostate following radical perineal prostatectomy (RPP) for clinically organ-confined disease. Of 1662
men who underwent RPP performed by a single surgeon between January 1972 and January 1999, 692 patients (41.6%) aged a median
of 66.1 years were found to have extracapsular disease on pathological evaluation. The extent of disease was categorized as
either specimen-confined (n=355) or margin-positive (n=337). The histological grade of the cancer was characterized using the Gleason score. Time to biochemical failure, defined
as a prostate-specific antigen (PSA) level of ≥0.5 ng/ml, and cancer-associated survival were the end points of our outcome
analysis using the Kaplan-Meier product-limit method. The median time to cancer-associated death for patients with specimen-
confined and margin-positive disease was 18.5 and 13.1 years, respectively. After 5 years, 37% and 54% of the patients with
specimen-confined and margin-positive disease, respectively, had PSA failure. Prostate cancer patients with a Gleason score
of 5–6, 7, and 8–10 experienced a median time to cancer-associated death of 19.9, 19.2, and 10.5 years, respectively. A subset
of patients undergoing adjunctive radiation therapy (XRT) relapsed biochemically after a median period of approximately 18 months.
RPP provides a substantial disease-control benefit in patients with specimen-confined cancer. The time to biochemical failure
and the time to cancer-associated death are significantly influenced by the biology of the underlying disease, necessitating
long-term follow-up in the outcome analysis of any modality of treatment for prostate cancer. A benefit of early adjunctive
XRT for local failure remains to be determined. 相似文献
70.