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91.
The Personal Development Study (PDS) was administered to four diagnostic groups, which included 89 hospitalized alcoholics, 336 unmarried mothers, 159 college students, and 387 chronic institutionalized schizophrenics. The PDS data from the four groups were factor analyzed separately by Varimax rotation of principal component factors. Cluster analysis methods were used to compare the separate diagnostic group factors with the overall factors previously reported by Pishkin and Thorne (1977). Only a few close fits of the diagnostic group factors showed large differences in item composition, order of emergence of factors and size of loadings between groups. Because many items and factors could be interpreted in terms of several alternative theoretical systems, interpretations were based on the clinical meanings of items and clusters in terms of integration theory (Thorne, 1976). 相似文献
92.
Andrew I. Mikhail Peter L. Nagy Katherine Manta Nicholas Rouse Alexander Manta Sean Y. Ng Michael F. Nagy Paul Smith Jian-Qiang Lu Joshua P. Nederveen Vladimir Ljubicic Mark A. Tarnopolsky 《The Journal of clinical investigation》2022,132(10)
BackgroundMyotonic dystrophy type 1 (DM1) is a complex life-limiting neuromuscular disorder characterized by severe skeletal muscle atrophy, weakness, and cardiorespiratory defects. Exercised DM1 mice exhibit numerous physiological benefits that are underpinned by reduced CUG foci and improved alternative splicing. However, the efficacy of physical activity in patients is unknown.MethodsEleven genetically diagnosed DM1 patients were recruited to examine the extent to which 12 weeks of cycling can recuperate clinical and physiological metrics. Furthermore, we studied the underlying molecular mechanisms through which exercise elicits benefits in skeletal muscle of DM1 patients.RESULTSDM1 was associated with impaired muscle function, fitness, and lung capacity. Cycling evoked several clinical, physical, and metabolic advantages in DM1 patients. We highlight that exercise-induced molecular and cellular alterations in patients do not conform with previously published data in murine models and propose a significant role of mitochondrial function in DM1 pathology. Finally, we discovered a subset of small nucleolar RNAs (snoRNAs) that correlated to indicators of disease severity.ConclusionWith no available cures, our data support the efficacy of exercise as a primary intervention to partially mitigate the clinical progression of DM1. Additionally, we provide evidence for the involvement of snoRNAs and other noncoding RNAs in DM1 pathophysiology.Trial registrationThis trial was approved by the HiREB committee (no. 7901) and registered under ClinicalTrials.gov ().FundingNeil and Leanne Petroff. Canadian Institutes of Health Research Foundation (no. 143325). NCT04187482相似文献
93.
Michael Nazarkovsky Albina Mikhraliieva Carlos A. Achete Luiz Anastacio Alves Joyce Araujo Brulio S. Archanjo Jos Júnior Frana de Barros Liana Monteiro da Fonseca Cardoso Jos Nelson S. S. Couceiro Fernanda Davi Marques Bruno S. Oliveira Rafael Nascimento Dias de Souza Ayla Josma Teixeira Thiago L. Vasconcelos Vladimir Zaitsev 《RSC advances》2022,12(23):14342
Rational synthesis and simple methodology for the purification of large (35–45 nm in lateral size) and flat (1.0–1.5 nm of height) nitrogen-doped graphene oxide quantum dots (GOQDs) are presented. The methodology allows robust metal-free and acid-free preparation of N-GOQDs with a yield of about 100% and includes hydrothermal treatment of graphene oxide with hydrogen peroxide and ammonia. It was demonstrated that macroscopic impurities can be separated from N-GOQD suspension by their coagulation with 0.9% NaCl solution. Redispersible in water and saline solutions, particles of N-GOQDs were characterized using tip-enhanced Raman spectroscopy (TERS), photoluminescent, XPS, and UV-VIS spectroscopies. The size and morphology of N-GOQDs were studied by dynamic light scattering, AFM, SEM, and TEM. The procedure proposed allows nitrogen-doped GOQDs to be obtained, having 60–51% of carbon, 34–45% of oxygen, and up to 7.2% of nitrogen. The N-GOQD particles obtained in two hours of synthesis contain only pyrrolic defects of the graphene core. The fraction of pyridine moieties grows with the time of synthesis, while the fraction of quaternary nitrogen declines. Application of TERS allows demonstration that the N-GOQDs consist of a graphene core with an average crystallite size of 9 nm and an average distance between nearest defects smaller than 3 nm. The cytotoxicity tests reveal high viability of the monkey epithelial kidney cells Vero in the presence of N-GOQDs in a concentration below 60 mg L−1. The N-GOQDs demonstrate green luminescence with an emission maximum at 505 nm and sedimentation stability in the cell culture medium.This paper reveals the methodology for robust preparation of purified nitrogen-doped graphene oxide quantum dots with non-cytotoxic activity against monkey epithelial kidney cells (Vero ATCC® CCL-81™). 相似文献
94.
Ljiljana Vlaški Dragan Dankuc Nada Vučković Vladimir Kljajić Danijela Dragičević Slobodanka Lemajić-Komazec 《Central European Journal of Medicine》2012,7(3):344-348
Aim
The aim of this paper is to present two case reports of patients with hemangiomas of the external auditory canal, and to overview all cases published in English language literature so far. 相似文献95.
Jan-Peter van Wieringen Jan Booij Vladimir Shalgunov Philip Elsinga Martin C. Michel 《Naunyn-Schmiedeberg's archives of pharmacology》2013,386(2):135-154
Dopamine D2 receptors, similar to other G-protein-coupled receptors, exist in a high- and low-affinity state for agonists. Based upon a review of the methods for detecting D2 receptor agonist high-affinity states, we discuss alterations of such states in animal models of disease and the implications of such alterations for their labelling with positron emission tomography (PET) and single-photon emission computed tomography (SPECT) tracers. The classic approach of detecting agonist high-affinity states compares agonist competition for antagonist radioligands, in most cases using [3H]-spiperone as the radioligand; alternative approaches and radioligands have been proposed, but their claimed advantages have not been substantiated by other investigators. In view of the advantages and disadvantages of various techniques, we critically have reviewed reported findings on the detection of D2 receptor agonist high-affinity states in a variety of animal models. These data are compared to the less numerous findings from human in vivo studies based on PET and SPECT tracers; they are interpreted in light of the finding that D2 receptor agonist high-affinity states under control conditions may differ between rodent and human brain. The potential advantages of agonist ligands in studies of pathophysiology and as diagnostics are being discussed. 相似文献
96.
We propose an adaptive procedure for dose-finding in clinical trials when the primary efficacy endpoint is continuous. We model the mean of the efficacy endpoint, given the dose, as a four-parameter logistic function. The efficacy endpoint at each dose is distributed according to either a normal or a gamma distribution. We consider the cases of fixed variance and fixed coefficient of variation assuming them to be both known and unknown. The analytic formulae for the Fisher information matrix are obtained, which are used to build the locally and adaptive D -optimal designs. 相似文献
97.
98.
Vladimir Petoukhov Stefan Rahmstorf Stefan Petri Hans Joachim Schellnhuber 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(14):5336-5341
In recent years, the Northern Hemisphere has suffered several devastating regional summer weather extremes, such as the European heat wave in 2003, the Russian heat wave and the Indus river flood in Pakistan in 2010, and the heat wave in the United States in 2011. Here, we propose a common mechanism for the generation of persistent longitudinal planetary-scale high-amplitude patterns of the atmospheric circulation in the Northern Hemisphere midlatitudes. Those patterns—with zonal wave numbers m = 6, 7, or 8—are characteristic of the above extremes. We show that these patterns might result from trapping within midlatitude waveguides of free synoptic waves with zonal wave numbers k ≈ m. Usually, the quasistationary dynamical response with the above wave numbers m to climatological mean thermal and orographic forcing is weak. Such midlatitude waveguides, however, may favor a strong magnification of that response through quasiresonance. 相似文献
99.
100.