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排序方式: 共有4341条查询结果,搜索用时 15 毫秒
31.
Jonathan T. Sims Venkatesh Krishnan Ching-Yun Chang Sarah M. Engle Giacomo Casalini George H. Rodgers Nicoletta Bivi Brian J. Nickoloff Robert J. Konrad Stephanie de Bono Richard E. Higgs Robert J. Benschop Silvia Ottaviani Anabela Cardoso Ajay Nirula Mario Corbellino Justin Stebbing 《The Journal of allergy and clinical immunology》2021,147(1):107-111
32.
It is well known that cardiac troponin C (cTnC) regulates the association of force-generating myosin cross-bridges. We report here evidence for an additional role for cTnC. This hypothesis states that Car2+ binds more strongly to cTnC when force-generating myosin cross-bridges are attached to actin and that removal of this bound Ca2+ accelerates the dissociation of force-generating myosin cross-bridges. Intact Fura-2-loaded rat papillary muscles and skinned (permeabilized) ventricular preparations were used. The preparations were mounted in the Guth Muscle Research System which is capable of measuring simultaneously fluorescence and force in response to length perturbations. All mechanical perturbations of muscle length (isotonic shortening, quick stretches and releases, and length vibrations) which cause dissociation of force-generating myosin cross-bridges during a twitch resulted in Ca2+ being released from troponin as judged from changes in the Ca2+ transients (Fura-2 (340/380) fluorescence ratio). Thus dissociation of force-generating myosin cross-bridges cause Ca2+ to be released from cTnC. Conversely, it would be expected that removal of strongly bound Ca2+ from cTnC would result in an increase in the rate of dissociation of force-generating myosin cross-bridges. To test this hypothesis actomyosin ATPase (NADH fluorescence change) and isometric force were measured in skinned cardiac preparations. The ratio of the ATPase/Force is proportional to the rate constant (gapp) for the dissociation of force-generating myosin cross-bridges. The data showed that decreasing the amount of Ca2+ bound to cTnC in skinned cardiac fibers caused an increase in the ratio of ATPase/Force, the rate of dissociation (gapp) of force-generating myosin cross-bridges. 相似文献
33.
34.
Stefan Schwarz Nina Rahimi Daria Kifjak Moritz Muckenhuber Martin Watzenböck Alberto Benazzo Peter Jaksch Sylvia Knapp Walter Klepetko Konrad Hoetzenecker the Vienna Lung Transplant Group 《American journal of transplantation》2021,21(6):2132-2144
Objectifying donor lung quality is difficult and currently there is no consensus. Several donor scoring systems have been proposed in recent years. They all lack large-scale external validation and widespread acceptance. A retrospective evaluation of 2201 donor lungs offered to the lung transplant program at the Medical University of Vienna between January 2010 and June 2018 was performed. Five different lung donor scores were calculated for each offer (Oto, ET, MALT, UMN-DLQI, and ODSS). Prediction of organ utilization, 1-year graft survival, and long-term outcome were analyzed for each score. 1049 organs were rejected at the initial offer (group I), 209 lungs declined after procurement (group II), and 841 lungs accepted and transplanted (group III). The Oto score was superior in predicting acceptance of the initial offer (AUC: 0.795; CI: 0.776–0.815) and actual donor utilization (AUC: 0.660; CI: 0.618–0.701). Prediction of 1-year graft survival was best using the MALT score, Oto score, and UMN-DLQI. Stratification of early outcome by MALT was significant for length of mechanical ventilation (LMV), PGD3 rates, ICU stay and hospital stay, and in-hospital-mortality, respectively. To the best of our knowledge, this study is the largest validation analysis comparing currently available donor scores. The Oto score was superior in predicting organ utilization, and MALT score and UMN-DLQI for predicting outcome after lung transplantation. 相似文献
35.
G. Aumüller Paul-Martin Holterhus Lutz Konrad Burkhard von Rahden Olaf Hiort Murielle Esquenet Guido Verhoeven 《Anatomy and embryology》1998,197(3):199-208
As it is suggested that the androgen receptor mechanism is required for prostatic development, we attempted to determine
the appearance, expression and distribution of the androgen receptor in embryonic, infantile and pubertal human prostate.
Using mono- and polyclonal antibodies and a digoxigenin-labeled 713 bp riboprobe, the androgen receptor expression in paraffin
sections of fetal, infantile, and pubertal prostates was studied at the protein and RNA level. Under highly standardized conditions,
application of the polyclonal antibodies resulted in a weak cytoplasmic and nuclear labeling of the epithelium of fetal glands.
No immunoreaction was obtained with monoclonal antibodies. Applying the polyclonal antibody to pubertal and adult specimens,
immunoreactivity of the androgen receptor was positive in nuclei of adluminal and basal epithelial cells, in interstitial
and vascular smooth muscle cells and vascular endothelium, whereas ganglionic cells and enteroendocrine cells were negative.
In situ hybridization with the digoxigenin-labeled riboprobe gave clear positive results already in epithelium of very young
fetal specimens. A semiquantitative visual evaluation of in situ hybridizations showed that intermediate intensity of expression
was increased in pubertal and adult specimens, whereas strong expression was reduced in prostatic epithelium. Conclusions:
The essential findings are: (1) an early expression of androgen receptor mRNA in the fetal prostate; (2) no immunoreaction
of monoclonal antibodies against the androgen receptor in the same specimens, (3) a decrease of androgen receptor mRNA expression,
but increase in immunoreactivity of the androgen receptor protein with the onset of glandular maturation during puberty.
Accepted: 29 September 1997 相似文献
36.
The effects of in vitro hemodilution with gelatin, hydroxyethyl starch, and lactated Ringer's solution on markers of coagulation: an analysis using SONOCLOT 总被引:12,自引:0,他引:12
Blood-saving strategies have recently been established to avoid allogeneic transfusion during surgery or after trauma. This includes an expanding use of crystalloids and colloids. These solutions interfere with coagulation systems, but quantitative measurements are still lacking. The SONOCLOT (Sienco Company, Morrison, CO) analysis (SCT), a viscoelastic test, measures clot formation and includes information on the cellular, as well as the plasmatic coagulation, system. To quantify hemodilutional effects on in vitro coagulation, we studied gelatin (G), hydroxyethyl starch 6% (HES; molecular weight 450,000), and lactated Ringer's solution (RL) in 33% and 66% dilutions measuring routines laboratory and SCT variables. Hemodilution with RL tended to increase in vitro coagulability. Among the tested colloids, G had the least impact on markers of coagulation. G33% did not differ significantly from the undiluted control group. HES had the largest impact on markers of coagulation compared with G and RL. In conclusion, SCT provides a fast and easy to perform bedside test to quantify in vitro hemodilution. IMPLICATIONS: The effects of progressive hemodilution on coagulation are difficult to measure. SONOCLOT analyses provide an easy to perform test with fast information on cellular and plasmatic coagulation properties. Among colloids, hydroxyethyl starch has the largest impact on markers of coagulation compared with gelatin or lactated Ringer's solution. 相似文献
37.
Connections between transsexualism and delinquency have been considered in only a few publications to date. The authors report on a forensic psychiatric case with a transsexual development after committing an offence based on sexual deviations. Transsexualism in this context seems to represent an attempt for the symbolic solution of a conflict of identity. This should be interpreted in the context of psychotherapy and not be misunderstood as a symptom proving the diagnosis of manifest transsexualism by orientation on pure phenomenological criteria. 相似文献
38.
39.
Thomas Dierks Stefan Barta Lothar Demisch Klaus Schmeck Ekkehart Englert Andrea Kewitz Konrad Maurer Fritz Poustka 《Psychopharmacology》1999,146(1):101-107
Rationale: The intensity dependence of the auditory evoked potentials (AEP) has been suggested to be a specific biological marker of
central serotonergic activity. Objective: While previous studies used circumstantial evidence to support this hypothesis, we manipulated (decreased) cerebral levels
of serotonin directly by using tryptophan depletion. Methods: Twelve healthy young subjects were investigated using placebo and two different amino acid mixtures in a double blind cross
over design on three different occasions. AEPs recorded during tryptophan depletion were analyzed by dipole analysis and regional
sources using methods published in the literature. Results: For none of the mixtures a significant effect of tryptophan depletion was found. There was a trend towards reduced intensity
dependency after tryptophan depletion, especially in the right hemisphere. This reduction correlated with the amount of reduced
tryptophan in plasma. Conclusions: The results indicate, in contrast to earlier indirect studies, that the intensity dependence of AEPs is not a specific marker
of central serotonergic activity.
Received: 8 March 1999 / Final version: 25 May 1999 相似文献
40.
The incudostapedial joint was studied in tomograms of 370 normal and 80 diseased middle ears. The Guillen view was found to be superior to the anteroposterior view in demonstrating this joint in normal middle ears (85% and 62% visualization, respectively). In the presence of disease, visualization was markedly reduced to 19%; this lack of visualization is a nonspecific finding since early cholesteatomas, chronic otitis media, and retraction pockets could not be differentiated radiologically. Nonvisualization of the incudostapedial joint in the Guillen view is a more objective indicator of middle ear disease than such terms as "indistinct of hazy" middle ear cavities. 相似文献