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排序方式: 共有710条查询结果,搜索用时 15 毫秒
1.
Sonoelasticity imaging of prostate cancer: in vitro results 总被引:2,自引:0,他引:2
2.
Screening for early ovarian cancer 总被引:5,自引:0,他引:5
3.
X-ray structure of a cyclophilin B/cyclosporin complex: comparison with cyclophilin A and delineation of its calcineurin-binding domain. 总被引:6,自引:0,他引:6
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V Mikol J Kallen M D Walkinshaw 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(11):5183-5186
The crystal structure of a complex between recombinant human cyclophilin B (CypB) and a cyclosporin A (CsA) analog has been determined and refined at 1.85-A resolution to a crystallographic R factor of 16.0%. The overall structures of CypB and of cyclophilin A (CypA) are similar; however, significant differences occur in two loops and at the N and C termini. The CsA-binding pocket in CypB has the same structure as in CypA and cyclosporin shows a similar bound conformation and network of interactions in both CypB and CypA complexes. The network of the water-mediated contacts is also essentially conserved. The higher potency of the CypB/CsA complex versus CypA/CsA in inhibiting the Ca(2+)- and calmodulin-dependent protein phosphatase calcineurin is discussed in terms of the structural differences between the two complexes. The three residues Arg90, Lys113, and Ala128 and the loop containing Arg158 on the surface of CypB are likely to modulate the differences in calcineurin inhibition between CypA and CypB. 相似文献
4.
The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses. 相似文献
5.
Detection of reactive oxygen species (ROS) and apoptosis in human fragmented embryos 总被引:8,自引:2,他引:8
Yang HW; Hwang KJ; Kwon HC; Kim HS; Choi KW; Oh KS 《Human reproduction (Oxford, England)》1998,13(4):998-1002
In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture
environment differs from in-vivo conditions in that the oxygen
concentration is higher, and in such conditions the mouse embryos show a
higher concentration of reactive oxygen species (ROS) in simple culture
media. ROS are believed to cause damage to cell membranes and DNA
fragmentation in somatic cells. This study was conducted to ascertain the
level of H2O2 concentration within embryos and the morphological features
of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31
fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was
obtained from the IVF-embryo transfer programme. The relative intensity of
H2O2 concentrations within embryos was measured using
2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence
imaging and DNA fragmentation was observed with transmission electron
microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations
were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/-
SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and
unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed
only in fragmented embryos, and was absent in non-fragmented embryos.
Electron microscopic findings confirmed apoptotic bodies and cytoplasmic
condensation in the fragmented blastomeres. We conclude that there is a
direct relationship between increased H2O2 concentration and apoptosis, and
that further studies should be undertaken to confirm these findings.
相似文献
6.
Kallen Michael A. Brown Heather E. Hatton Joeffrey R. Doyle William A. Murphy Ryan Elliott Ryan Gutierrez Mark A. Catherwood Emma L. Pitman Heather P. Liu Vincent X. Gershon Richard C. 《Quality of life research》2022,31(7):2201-2212
Quality of Life Research - To develop two item content-matched, precise, score-level targeted inpatient physical function (PF) short form (SF) measures: one clinician-reported, one... 相似文献
7.
8.
Pathways to care for alcohol use disorders 总被引:1,自引:0,他引:1
9.
Nick Wlazlo Marleen M.J. van Greevenbroek Isabel Ferreira Eugene J.H.M. Jansen Edith J.M. Feskens Carla J.H. van der Kallen Casper G. Schalkwijk Bert Bravenboer Coen D.A. Stehouwer 《Metabolism: clinical and experimental》2012,61(12):1787-1796
ObjectiveTo investigate the role of low-grade inflammation and insulin resistance (HOMA2-IR) in adiposity-related increases in serum complement factor 3 (C3). Although C3 has been linked to type 2 diabetes and cardiovascular diseases, and C3 levels are closely related to body fat, the underlying mechanisms explaining this association are still unknown.MethodsAdiposity measures (including BMI, waist circumference (WC), sagittal diameter and several skinfolds), HOMA2-IR and markers of inflammation (hs-CRP, IL-6, SAA, haptoglobin, ceruloplasmin, sICAM-1) were determined in 532 individuals (62% men, mean age 59 ± 6.9 yrs) from the Cohort on Diabetes and Atherosclerosis Maastricht study. Markers of inflammation were standardized and compiled into an averaged inflammation score. Cross-sectional associations between adiposity measures and C3 and the mediating role of low-grade inflammation and/or HOMA2-IR herein were analysed with multiple linear regression models.ResultsAdiposity measurements were significantly associated with C3 levels, with the strongest (adjusted) associations found for WC (β = 0.383; 95%CI 0.302–0.464) and sagittal diameter (β = 0.412; 95%CI 0.333-0.490). Further adjustment for inflammation and HOMA2-IR attenuated these associations to β = 0.115 (95%CI 0.030-0.200) and β = 0.163 (95%CI 0.082-0.244) respectively. Multiple mediation analyses showed that inflammation [β = 0.090 (95%CI 0.060–0.126)] and HOMA2-IR [β = 0.179 (95%CI 0.128–0.236)] each explained, independently of one another, a significant portion of the association between WC and C3 (23% and 47%, respectively). Similar mediation by inflammation (19-27%) and HOMA2-IR (37-56%) was found for other adiposity measures.ConclusionSystemic low-grade inflammation and insulin resistance may represent two independent pathways by which body fat leads to elevated C3 levels. 相似文献
10.