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191.
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193.
Background
The purpose of this study was to determine the effects of the pre-workout supplement Assault? (MusclePharm, Denver, CO, USA) on upper and lower body muscular endurance, aerobic and anaerobic capacity, and choice reaction time in recreationally-trained males. Subjective feelings of energy, fatigue, alertness, and focus were measured to examine associations between psychological factors and human performance.Methods
Twelve recreationally-trained males participated in a 3-week investigation (mean +/- SD, age: 28 +/- 5 y, height: 178 +/- 9 cm, weight: 79.2 +/- 15.7 kg, VO2max: 45.7 +/- 7.6 ml/kg/min). Subjects reported to the human performance laboratory on three separate occasions. All participants completed a baseline/familiarization day of testing that included a maximal graded exercise test for the determination of aerobic capacity (VO2max), one-rep maximum (1-RM) for bench and leg press to determine 75% of 1-RM, choice reaction tests, and intermittent critical velocity familiarization. Choice reaction tests included the following: single-step audio and visual, one-tower stationary protocol, two-tower lateral protocol, three-tower multi-directional protocol, and three-tower multi-directional protocol with martial arts sticks. Subjects were randomly assigned to ingest either the supplement (SUP) or the placebo (PL) during Visit 2. Subjects were provided with the cross-over treatment on the last testing visit. Testing occurred 20 min following ingestion of both treatments.Results
Significant (p < 0.05) main effects for the SUP were observed for leg press (SUP: 13 ± 6 reps, PL: 11 ± 3 reps), perceived energy (SUP: 3.4 ± 0.9, PL: 3.1 ± 0.8), alertness (SUP: 4.0 ± 0.7, PL: 3.5 ± 0.8), focus (SUP: 4.1 ± 0.6, PL: 3.5 ± 0.8), choice reaction audio single-step (SUP: 0.92 ± 0.10 s, PL: 0.97 ± 0.11 s), choice reaction multi-direction 15 s (SUP: 1.07 ± 0.12 s, PL: 1.13 ± 0.14 s), and multi-direction for 30 s (SUP: 1.10 ± 0.11 s, PL: 1.14 ± 0.13 s).Conclusions
Ingesting the SUP before exercise significantly improved agility choice reaction performance and lower body muscular endurance, while increasing perceived energy and reducing subjective fatigue. These findings suggest that the SUP may delay fatigue during strenuous exercise. 相似文献194.
Studies on levamisole--induced agranulocytosis 总被引:1,自引:0,他引:1
Thompson JS; Herbick JM; Klassen LW; Severson CD; Overlin VL; Blaschke JW; Silverman MA; Vogel CL 《Blood》1980,56(3):388-396
Widespread clinical trials of leavo-tetramisole (levamisole) as an immunopotentiating agent in rheumatoid arthritis, metastatic carcinoma, and immunodeficiency states have been complicated by agranulocytosis (AGC) in 2.5%-13% of patients. Other than a relationship with prolonged high dosage, very little is known regarding the pathogenesis of levamisole-induced AGC. Whereas leukoagglutination was negative, fluorochromatic microgranulocytotoxicity (GCY) tests were positive with serum from 10 of 10 acutely neutropenic patients. The antibody was IgM, reacted with 100% of unrelated granulocytes, but not with T or B lymphocytes. Some sera also reacted with monocytes and the myeloid cell line, K-562. Tests for antigen-antibody complexes or cold autoantibodies were negative. Although clinical evidence strongly suggests a haptene (drug) mechanism, in vitro mixing experiments were also negative. An alternative choice parallels the model of aldomet- induced Coombs'-positive hemolytic anemia. Finally, GCY first became positive 2-3 mo prior to the onset of AGC on two patients, suggesting the possibility of identifying those at risk well before the onset of neutropenia. 相似文献
195.
Cutaneous T cell lymphoma: characterization by monoclonal antibodies 总被引:10,自引:0,他引:10
Monoclonal antibodies to human T cells permit the characterization of the surface phenotype of cutaneous T cell lymphoma (CTCL). The majority of CTCL cells are reactive with OKT1 and OKT3 monoclonals, which identify peripheral T cells and mature thymocytes. The neoplastic cells also react with OKT4, which recognizes the inducer T cell subset; they are, however, unreactive with OKT5 monoclonal, which identifies cytotoxic/suppressor T cell subsets. These data are in agreement with previous functional studies demonstrating that CTCL is a neoplasm of inducer (helper) T cells. 相似文献
196.
Stem cell factor enhances the survival but not the self-renewal of murine hematopoietic long-term repopulating cells 总被引:4,自引:7,他引:4
The effects of stem cell factor (SCF) have been tested on a murine bone marrow subpopulation (RH123lo, Lin-, Ly6A/E+) that is highly enriched for long-term hematopoietic repopulating cells. SCF maintained cells from this population with long-term repopulating ability for up to 10 days in vitro. However, compared with freshly isolated cells, the level of engraftment in vivo by the cultured cells declined during the in vitro culture period, suggesting that SCF alone was unable to stimulate the self-renewal of long-term repopulating cells. By direct visualization of cultures, only small numbers of cells survived and rarely underwent cell division. However, SCF did directly stimulate proliferation of a population (Rh123med/hi,Lin-,Ly6A/E+) enriched for short-term repopulating cells. These data suggest that stem cell differentiation is associated with the development of mitogenic activity by SCF at least in some progenitor cell populations. 相似文献
197.
The repopulation potential of fetal liver hematopoietic stem cells in mice exceeds that of their liver adult bone marrow counterparts 总被引:2,自引:7,他引:2
Varying, limiting numbers of unseparated or purified cells (Ly-5.1), either from 14.5-day-old fetal liver (FL) or from adult bone marrow (BM) were coinjected with 10(5) unseparated BM cells (Ly-5.2) into lethally irradiated adult C57B1/6 recipients (Ly-5.2). The kinetics of donor cell repopulation of the lymphoid and myeloid compartments by Ly- 5.1+ donor hematopoietic stem cells (ie, competitive repopulation units [CRU]) were monitored at various time points after the transplantation by Ly-5 analysis of the peripheral white blood cells (WBC). Recipients that had received on average less than 2 adult BM or FL CRU did not show a significant difference in the level of donor-reconstitution when analyzed 4 weeks after the transplantation, However, at 8 and 16 weeks, the FL recipients showed a significantly higher percentage of donor- derived nucleated peripheral blood cells than did the recipients of adult BM cells. Analysis of individual mice showed that approximately 80% of the recipients of FL CRU showed an increase in mature WBC output between 4 and 8 weeks after transplantation, whereas this occurred in less than 40% in the recipients of adult BM cells. In addition to this effect on mature cell output, the cellularity of the reconstituted BM was significantly higher in recipients of FL CRU than in recipients of adult BM CRU, even at 7 to 9 months after transplantation, which is consistent with an increased clonal expansion of FL CRU. When marrow cells from primary recipients of FL CRU were injected into secondary recipients, a significantly higher percentage of these mice showed donor-reconstitution of their lymphoid and myeloid compartments (P < .01) and to a greater extent (P < .008) as compared with mice that had received marrow cells from primary recipients of similar numbers of adult BM CRU. Taken together, these results show that individual FL CRU exhibit a greater proliferative activity in vivo than similar cells from adult BM that is accompanied by a greater production of daughter CRU. 相似文献
198.
Murine hematopoietic stem and progenitor cells: I. Enrichment and biologic characterization 总被引:2,自引:5,他引:2
Murine bone marrow cells were fractionated by fluorescence-activated cell sorting into Rh123lo Lin- c-kit+ Ly6A+, Rh123hi Lin-c-kit+ Ly6A+, and Lin- c-kit+ Ly6A- populations within which most, if not all, of the hematopoietic activities of the marrow resided. The Rh123lo Lin- c- kit+Ly6A+ cells, which consist exclusively of small- or medium-sized lymphocyte-like cells, are highly enriched for long-term hematopoietic in vivo repopulating cells. The enrichment factor for these cells from the marrow was estimated as 2,000-fold. The Rh123hi Lin- c-kit+ Ly6A+ cells, although also highly enriched for day-12 spleen colony-forming units, were relatively depleted of long-term in vivo repopulation capacity. Most, if not all Lin- c-kit+ Ly6A- cells were Rb123hi. In contrast to both Rh123lo and Rh123hi Lin- c-kit+ Ly6A+ stem cell populations, the Lin- c-kit+ Ly6A- cells can be stimulated to proliferate in vitro in the presence of single cytokines, which is a characteristic of committed progenitor cells. No marked synergistic interactions between individual cytokines were observed with this cell population. Both Rh123hi Lin- c-kit+ Ly6A+ mature stem cell and Lin- c- kit+ Ly6A- progenitor cell populations displayed in vivo repopulation kinetics resembling those of the putative short-term hematopoietic repopulating cells. 相似文献
199.
200.
Peters A Ehlers M Blank B Exler D Falk C Kohlmann T Fruehwald-Schultes B Wellhoener P Kerner W Fehm HL 《Archives of internal medicine》2000,160(13):1993-1999
BACKGROUND: Abnormalities in cardiac function, eg, arrhythmias and congestive heart failure, often accompany thyrotoxicosis. A relationship between thyroid hormone excess and the cardiac complications of angina pectoris and myocardial infarction (MI) remains largely speculative. METHODS: The results of thyroid function studies on blood samples drawn from a total of 1049 patients (aged 40 years or older) immediately on emergency medical admission were related to frequencies of angina pectoris and myocardial infarction as determined according to current diagnostic algorithms. After 3 years, those patients who had initially presented with angina pectoris or acute MI were observed for subsequent coronary events; of these (n=185), 98% of the subjects (n=181) could be reevaluated. RESULTS: On hospital admission, the relative rate of angina pectoris and MI was markedly high (odds ratio, 2.6; 95% confidence interval, 1.3-5.2; P=.007) in patients with elevated serum free and total triiodothyronine (T(3)) levels. An initially elevated free T(3) level was a risk factor for subsequent coronary events during the 3-year follow-up (adjusted odds ratio, 4.8; 95% confidence interval, 1.3-17.4; P=.02). CONCLUSIONS: An elevation of serum free T(3) levels at hospital admission is associated with a 2.6-fold greater likelihood of the presence of a coronary event. Moreover, an initially elevated T(3) level is associated with a 3-fold higher risk of developing a subsequent coronary event during the next 3 years. Excess T(3) seemed to be a factor associated with the development and progression of acute myocardial ischemia. 相似文献