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81.
A quantitative ultrastructural study of collagen fibril formation in the healing extensor digitorum longus tendon of the rat 总被引:1,自引:0,他引:1
Cara Matthew M. J. Moore Lorna Campbell 《The Journal of hand surgery, European volume》1987,12(3):313-320
A study was made of collagen fibril populations in healing tendon using a window lesion in rat extensor tendon. Two environments were thus created. One (the lesion area) where stress levels were reduced; the other (the non-lesion area) where stress levels were increased. In both areas a population of small diameter (less than 50nm) collagen fibrils were synthesized. Lesion area fibrils increased their diameter only slowly. Non-lesion area fibrils added to a population which increased its diameter distribution comparatively rapidly. It is suggested that in the lesion area fibrils were synthesized in response to tissue damage and low levels of stress. These may be of type III collagen. In the non-lesion area fibrils were synthesized in response to raised levels of stress. These may be of type I collagen. Implications of these events, especially as they might relate to gap formation in flexor tendon surgery are discussed. 相似文献
82.
Craig P. Dobson Maria Teresa La Rovere Cara Olsen Marino Berardinangeli Marco Veniani Paolo Midi Luigi Tavazzi Mark Haigney 《Journal of electrocardiology》2009,42(6):500-504
Background
Previous studies have shown that increased temporal variability of repolarization, as reflected by QT interval variability measured for 10 minutes, predicted spontaneous ventricular arrhythmias in implantable cardioverter defribrillator patients, but it is unclear how these measures perform in 24-hour recordings.Methods
Twenty-four-hour digital Holter recordings from 372 subjects with chronic heart failure enrolled in Gruppo Italiano per lo Studio della Sopravvivenza nell'Insufficienza Cardiaca, (GISSI) Heart Failure study were analyzed using a template-matching, semiautomatic algorithm to measure QT and heart rate time series in sequential 5-minute epochs for 24 hours. QT variability was expressed as normalized QT variance (QTVN) or as the log ratio of the QTVN over normalized heart rate variance (QT variability index, or QTVI).Results
A pronounced diurnal variation was seen in both QTVI and QTVN. Both were lowest in the midnight to 6 am time frame and increased throughout the day, peaking at noon to 6 pm, then decreasing 6 pm to midnight. For QTVI, all 4 time points were significantly different (P < .0001). QT variability index correlated with heart rate (r = 0.38, P < .0001) and was significantly higher for those in higher New York Heart Association (NYHA) classes (r = 0.22, P = .0003). Normalized QT variance did not correlate with heart rate or NYHA but correlated negatively with serum potassium (r = −0.22, P = .0002) and manifested the greatest increase during midmorning hours.Conclusions
Repolarization lability as reflected in QT variability has a pronounced diurnal variation and increases significantly after 6 am, the time of greatest arrhythmic risk. QT variability for 24 hours might improve risk prediction in chronic heart failure patients and should be tested in appropriate trials. 相似文献83.
Mary M. Sweeney Olga Rass Cara DiClemente Rebecca L. Schacht Hoa T. Vo Marc J. Fishman 《Journal of child & adolescent substance abuse》2018,27(4):211-226
Adolescent cannabis use is associated with working memory impairment. The present randomized controlled trial assigned adolescents ages 14 to 21 enrolled in cannabis use treatment to receive either working memory training (experimental group) or a control training (control group) as an adjunctive treatment. Cognitive function, drug use, and other outcomes were assessed before and after training. We observed few differences in cognitive, functional, or self-reported drug use outcomes as a function of training group, although tetrahydrocannabinol (THC) urinalysis results favored the experimental group. These findings are similar to previous studies in substance users, which have shown limited transfer effects for working memory training. 相似文献
84.
85.
Menor C Fueyo J Escribano O Piña MJ Redondo P Cara C Román ID Fernández-Moreno MD Guijarro LG 《Multiple sclerosis (Houndmills, Basingstoke, England)》2002,8(3):243-248
The present study was performed in order to obtain the thiopurine methyltransferase (TPMT) activity frequency distribution histogram in a Spanish population. A total of 3640 Spanish clinical laboratory samples were evaluated, which included 1249 patients with Crohn's disease, 589 with ulcerative colitis, 348 with multiple sclerosis (MS), 487 with several autoimmune diseases different from the above-mentioned diseases and 967 a donor group. We have measured the TPMT activity in red blood cells (RBCs) by a radiochemical method, using S-adenosyl-L-[methyl-3H]methionine as methyl donor. The different groups present in their entirety a normal distribution histogram and a wide range of TPMT activity from 0 to 41 U/ml RBCs. The differences found between the Spanish population TPMT activity frequency distribution histogram and the pattern previously described in a North American population were not due to azathioprine treatment or gender. The effect of autoimmune diseases on TPMT activity was evaluated: the enzymatic activity was similar in the donor group (19.9 +/- 6.3 U/ml RBCs) and in the patients with Crohn's disease (20.0 +/- 5.8 U/ml RBCs) and ulcerative colitis (19.7 +/- 6.1 U/ml RBCs); however, it decreased significantly (p<0.0001) in MS patients (17.1 +/- 6.1 U/ml RBCs) with respect to the donor group. In conclusion, our results show that the Spanish population TPMT distribution is closer to that of the Jewish population of Israel than to North American populations, and that in MS the enzymatic activity of TPMT decreases significantly. This observation may take into account the usage of azathioprine as therapeutic agent in Spanish MS patients. 相似文献
86.
Schirmer TN Dorflinger JM Marlow-O'Connor M Pendergrass JC Hartzell A All SD Charles D 《Progress in neuro-psychopharmacology & biological psychiatry》2009,33(1):25-32
The present study sought to identify abnormalities in activation in several brain regions in response to an auditory attention task in patients with schizophrenia. Ten patients and twenty healthy control participants were examined using Functional Magnetic Resonance Imaging (FMRI) measures acquired during an auditory attention task. Region of interest analyses of activation of targeted regions implicated in attention included: anterior cingulate cortex (ACC), dorsolateral prefrontal cortex (DLPFC), hippocampus, parahippocampal gyrus (PHG), and superior temporal gyrus (STG). The results indicated over-activation in patients with schizophrenia. While the control group showed notable coherence in activation within and across hemispheres the schizophrenia group showed relatively less coherence overall that was only present in the right hemisphere. These findings suggest that patients with schizophrenia show both an over-engagement of brain regions during attention task as well as a lack of communication among neural regions involved. 相似文献
87.
A specifically designed nanoconstruct associates,internalizes, traffics in cardiovascular cells,and accumulates in failing myocardium: a new strategy for heart failure diagnostics and therapeutics 下载免费PDF全文
Guillermo U. Ruiz‐Esparza Victor Segura‐Ibarra Andrea M. Cordero‐Reyes Keith A. Youker Rita E. Serda Ana S. Cruz‐Solbes Javier Amione‐Guerra Kenji Yokoi Dickson K. Kirui Francisca E. Cara Jesus Paez‐Mayorga Jose H. Flores‐Arredondo Carlos E. Guerrero‐Beltrán Gerardo Garcia‐Rivas Mauro Ferrari Guillermo Torre‐Amione 《European journal of heart failure》2016,18(2):169-178
88.
Broadly targeted human cytomegalovirus-specific CD4+ and CD8+ T cells dominate the memory compartments of exposed subjects 总被引:11,自引:0,他引:11 下载免费PDF全文
Sylwester AW Mitchell BL Edgar JB Taormina C Pelte C Ruchti F Sleath PR Grabstein KH Hosken NA Kern F Nelson JA Picker LJ 《The Journal of experimental medicine》2005,202(5):673-685
Human cytomegalovirus (HCMV) infections of immunocompetent hosts are characterized by a dynamic, life-long interaction in which host immune responses, particularly of T cells, restrain viral replication and prevent disease but do not eliminate the virus or preclude transmission. Because HCMV is among the largest and most complex of known viruses, the T cell resources committed to maintaining this balance have never been characterized completely. Here, using cytokine flow cytometry and 13,687 overlapping 15mer peptides comprising 213 HCMV open reading frames (ORFs), we found that 151 HCMV ORFs were immunogenic for CD4(+) and/or CD8(+) T cells, and that ORF immunogenicity was influenced only modestly by ORF expression kinetics and function. We further documented that total HCMV-specific T cell responses in seropositive subjects were enormous, comprising on average approximately 10% of both the CD4(+) and CD8(+) memory compartments in blood, whereas cross-reactive recognition of HCMV proteins in seronegative individuals was limited to CD8(+) T cells and was rare. These data provide the first glimpse of the total human T cell response to a complex infectious agent and will provide insight into the rules governing immunodominance and cross-reactivity in complex viral infections of humans. 相似文献
89.
Comorbid depressive symptoms and self‐esteem improve after either cognitive‐behavioural therapy or family‐based treatment for adolescent bulimia nervosa 下载免费PDF全文
Fabiola Valenzuela James Lock Daniel Le Grange Cara Bohon 《European eating disorders review》2018,26(3):253-258
This study examined the effect of family‐based treatment for bulimia nervosa (FBT‐BN) and cognitive behavioral therapy for adolescents (CBT‐A) on depressive symptoms and self‐esteem in adolescents with BN. Data were collected from 110 adolescents, ages 12–18, who met Diagnostic and Statistical Manual of Mental Disorders‐Fourth Edition, text revision criteria for BN or partial BN. Participants were randomly assigned to FBT‐BN or CBT‐A and completed measures of depressive symptoms and self‐esteem before and after treatment and at 6‐ and 12‐month follow‐up assessments. Depressive symptoms and self‐esteem significantly improved in both treatments, and neither treatment appeared superior on these clinical outcomes. Parents often worry whether FBT‐BN addresses comorbid depressive symptoms and low self‐esteem. Our findings address this concern, as they demonstrate that FBT‐BN does not differ from CBT‐A in improving depressive symptoms and self‐esteem, and both treatments result in symptom improvement. These findings can help clinicians guide families to choose a treatment that addresses BN and depressive symptoms and low self‐esteem. 相似文献
90.
In this study, soy waste biomass (SW) resulting from oil extraction was treated with alkaline solution, and the obtained material (Na-SW) was used as biosorbent for the removal of Pb(II), Cd(II), and Zn(II) ions from aqueous media. The performance of this biosorbent was examined in batch systems, at different initial metal ion concentrations and contact times (pH 3.4; 5 g of biosorbent/L). Isotherm and kinetic modeling was used to calculate the equilibrium and kinetics of the biosorption processes. The maximum biosorption capacity, calculated from the Langmuir isotherm model, followed the order Zn(II) (0.49 mmol/g) > Cd(II) (0.41 mmol/g) ≈ Pb(II) (0.40 mmol/g), while the kinetics of biosorption processes fit the pseudo-second-order model. Three cycles of biosorption/desorption were performed to estimate the reusability of Na-SW biosorbent, and the regeneration efficiency was higher than 97% in all cases. The practical applicability of Na-SW biosorbent in treating of wastewater contaminated with Pb(II), Cd(II), and Zn(II) ions was examined using simulated wastewater samples, and the main quality characteristics of the effluents obtained after treatment were evaluated. All these aspects highlight the potential applicability of Na-SW for large-scale wastewater treatment. 相似文献