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排序方式: 共有340条查询结果,搜索用时 46 毫秒
1.
Mehdi Kordi Jonathan Folland Stuart Goodall Nicos Haralabidis Tom Maden-Wilkinson Tejal Sarika Patel Jonathan Leeder Paul Barratt Glyn Howatson 《Scandinavian journal of medicine & science in sports》2020,30(2):227-237
Mechanical peak power output (PPO) is a determinant of performance in sprint cycling. The purpose of this study was to examine the relationship between PPO and putative physiological determinants of PPO in elite cyclists, and to compare sprint performance between elite sprint and endurance cyclists. Thirty-five elite cyclists (18 endurance; 17 sprint) performed duplicate sprint cycling laboratory tests to establish PPO and its mechanical components. Quadriceps femoris (QVOL) and hamstring muscle volume (HAMVOL) were assessed with MRI, vastus lateralis pennation angle (PθVL) and fascicle length (FLVL) were determined with ultrasound imaging, and neuromuscular activation of three muscles was assessed using EMG at PPO during sprint cycling. For the whole cohort, there was a wide variability in PPO (range 775-2025 W) with very large, positive, bivariate relationships between PPO and QVOL (r = .87), HAMVOL (r = .71), and PθVL (r = .81). Step-wise multiple regression analysis revealed that 87% of the variability in PPO between cyclists was explained by two variables QVOL (76%) and PθVL (11%). The sprint cyclists had greater PPO (+61%; P < .001 vs endurance), larger QVOL (P < .001), and BFVOL (P < .001) as well as more pennate vastus lateralis muscles (P < .001). These findings emphasize the importance of quadriceps muscle morphology for sprint cycling events. 相似文献
2.
Ruhani Nanavati Patrick Jasinski Demetri Adrahtas Antonios Gasparis Nicos Labropoulos 《Journal of vascular surgery》2018,67(2):536-541
Objective
Previous studies of men suggested that patients with varicocele may be leaner than the normal population. No such work exists in women with pelvic congestion syndrome (PCS). This study evaluated the correlation between body mass index (BMI) and PCS.Methods
A case-control study at a single institution was performed of women who had the objective diagnosis of PCS. Data were prospectively collected for 100 consecutive patients with PCS. BMI was calculated for every patient and categorized into normal weight (BMI <25), overweight (BMI 25-29.9), and obese (BMI >30). Diagnosis of PCS was made by ultrasound and venography. Mean BMI was compared with that of the general female population of the United States from 1999 to 2002. Furthermore, analyses included comparison of patients with and without ovarian vein dilation and pelvic varices.Results
There were 100 women with a median age of 44 years (range, 24-73 years). The mean BMI of the study group was 25 ± 5.6 kg/m2. The cohort was categorized into 59 women with normal BMI, 23 overweight women, and 18 obese women. The study cohort's BMI was less than that of the general U.S. female population (P = .02). The majority of the study group were white with lower BMI (P < .0001). Leg varicosities were more prevalent in obese patients (100% obese vs 81% normal BMI; P = .01). Patients with ovarian vein dilation had significantly lower BMI (24.1 ± 5.6 kg/m2 and 26.7 ± 5.4 kg/m2; P = .036). No differences were identified for pelvic varices or reflux.Conclusions
Women with PCS are more likely to have a normal BMI with ovarian vein dilation compared with obese women, who are more frequently affected by leg varicosities. 相似文献3.
Difference in outcomes after antibody‐mediated rejection between abo‐incompatible and positive cross‐match transplantations 下载免费PDF全文
Lionel Couzi Miriam Manook Ranmith Perera Olivia Shaw Zubir Ahmed Nicos Kessaris Anthony Dorling Nizam Mamode 《Transplant international》2015,28(10):1205-1215
Graft survival seems to be worse in positive cross‐match (HLAi) than in ABO‐incompatible (ABOi) transplantation. However, it is not entirely clear why these differences exist. Sixty‐nine ABOi, 27 HLAi and 10 combined ABOi+HLAi patients were included in this retrospective study, to determine whether the frequency, severity and the outcome of active antibody‐mediated rejection (AMR) were different. Five‐year death‐censored graft survival was better in ABOi than in HLAi and ABOi+HLAi patients (99%, 69% and 64%, respectively, P = 0.0002). Features of AMR were found in 38%, 95% and 100% of ABOi, HLAi and ABOi+HLAi patients that had a biopsy, respectively (P = 0.0001 and P = 0.001). After active AMR, a declining eGFR and graft loss were observed more frequently in HLAi and HLAi+ABOi than in ABOi patients. The poorer prognosis after AMR in HLAi and ABOi+HLAi transplantations was not explained by a higher severity of histological lesions or by a less aggressive treatment. In conclusion, ABOi transplantation offers better results than HLAi transplantation, partly because AMR occurs less frequently but also because outcome after AMR is distinctly better. HLAi and combined ABOi+HLAi transplantations appear to have the same outcome, suggesting there is no synergistic effect between anti‐A/B and anti‐HLA antibodies. 相似文献
4.
5.
Nadia J. Kershaw Artem Laktyushin Nicos A. Nicola 《Growth factors (Chur, Switzerland)》2014,32(1):1-10
AbstractSOCS3 (suppressor of cytokine signaling 3) inhibits the intracellular signaling cascade initiated by exposure of cells to cytokines. SOCS3 regulates signaling via two distinct mechanisms: directly inhibiting the catalytic activity of Janus kinases (JAKs) that initiate the intracellular signaling cascade and catalysing the ubiquitination of signaling components by recruiting components of an E3 ubiquitin ligase complex. Here we investigate the latter mode-of-action biochemically by reconstructing a SOCS3-based E3 ubiquitin ligase complex in vitro using fully purified, recombinant components and examining its ability to promote the ubiquitination of molecules involved in the cytokine signaling cascade. We show that SOCS3 is an active substrate recruitment module for a Cullin5-based E3 ligase and have defined the core protein components required for ubiquitination. SOCS3-induced polyubiquitination was rapid and could proceed through a number of different ubiquitin lysines. SOCS3 catalyzed the ubiquitination of both the IL-6 receptor common chain (gp130) and JAK2. 相似文献
6.
7.
Karamitsos TD Bull S Spyrou N Neubauer S Selvanayagam JB 《International journal of cardiology》2008,128(1):e34-e36
Tako-tsubo cardiomyopathy is a poorly understood syndrome. We report a case of a 76-year-old female patient with apical ballooning syndrome and features of left ventricular non-compaction that was followed up by Cardiovascular Magnetic Resonance (CMR) imaging. 相似文献
8.
Andrew J. Hapel Ming-Chiu Fung Nai-Ki Mak Carolyn Morris Donald Metcalf Nicos Nicola 《British journal of haematology》1992,82(3):488-493
Haemopoietic cells from A/J mice do not form colonies (proliferate) in response to interleukin-3 (multi-CSF, IL-3). We have examined different populations of cells from A/J mice and shown that, despite their failure to proliferate in response to IL-3, cells from bone marrow, spleen and the peritoneum all bound 125I-labelled IL-3. A wide variety of cell types bound IL-3 as determined by autoradiography, including promyelocytes, myelocytes, metamyelocytes, polymorphs, promonocytes, monocytes, eosinophils and lymphocytes, but not nucleated erythroid cells, and the proportion of each cell type binding label was similar when cells from A/J mice were compared with those of C57B1/6 and Balb/c mice. Bone marrow cells from A/J mice internalized interleukin-3 with normal kinetics and mRNA extracted from these cells contains the same species of IL-3 receptor and IL-3 receptor-like mRNAs as are found in the other strains. Collectively the data suggest that the failure of haemopoietic cells from A/J mice to proliferate in response to IL-3 is related to a selective defect in signalling to proliferation specific genes. This defect is apparently not related to internalization or processing of the IL-3/IL-3-receptor complex, but may be due to failure to activate appropriate accessory molecules in the cell. 相似文献
9.
Shili Xu Alexey N. Butkevich Roppei Yamada Yu Zhou Bikash Debnath Roger Duncan Ebrahim Zandi Nicos A. Petasis Nouri Neamati 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(40):16348-16353
Protein disulfide isomerase (PDI), an endoplasmic reticulum chaperone protein, catalyzes disulfide bond breakage, formation, and rearrangement. The effect of PDI inhibition on ovarian cancer progression is not yet clear, and there is a need for potent, selective, and safe small-molecule inhibitors of PDI. Here, we report a class of propynoic acid carbamoyl methyl amides (PACMAs) that are active against a panel of human ovarian cancer cell lines. Using fluorescent derivatives, 2D gel electrophoresis, and MS, we established that PACMA 31, one of the most active analogs, acts as an irreversible small-molecule inhibitor of PDI, forming a covalent bond with the active site cysteines of PDI. We also showed that PDI activity is essential for the survival and proliferation of human ovarian cancer cells. In vivo, PACMA 31 showed tumor targeting ability and significantly suppressed ovarian tumor growth without causing toxicity to normal tissues. These irreversible small-molecule PDI inhibitors represent an important approach for the development of targeted anticancer agents for ovarian cancer therapy, and they can also serve as useful probes for investigating the biology of PDI-implicated pathways. 相似文献
10.
Rodriguez HE Leon L Schalch P Labropoulos N Borge M Kalman PG 《Perspectives in vascular surgery and endovascular therapy》2005,17(2):155-166
The creation and maintenance of hemoaccess occupies a significant portion of most vascular and general surgery practices. In this article, the methods used to detect hemoaccess at risk for failure and the endovascular and surgical techniques used to prolong or restore their patency are reviewed. Also, the management of hemoaccess infection, aneurysmal degeneration, false aneurysm formation, and symptomatic arterial steal syndrome are described. 相似文献