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排序方式: 共有1073条查询结果,搜索用时 0 毫秒
81.
The Viral Activation Transfusion Study (VATS): rationale, objectives, and design overview 总被引:1,自引:0,他引:1
82.
Lambert CP Archer RL Carrithers JA Fink WJ Evans WJ Trappe TA 《Archives of physical medicine and rehabilitation》2003,84(8):1206-1210
OBJECTIVE: To evaluate the effectiveness of ingesting creatine monohydrate in elevating intramuscular creatine stores and improving exercise capacity in individuals with multiple sclerosis (MS). DESIGN: Randomized, double-blind, placebo-controlled, pre-posttrial. SETTING: A university-based exercise physiology laboratory. PARTICIPANTS: Sixteen individuals with relapsing-remitting MS (median Expanded Disability Status Scale score, 4.75; range, 1.5-6.0). INTERVENTION: Eight individuals with MS were randomized to the creatine group (20g/d of creatine monohydrate for 5d), and 8 others were randomized to the placebo group. Needle biopsies were performed on the vastus lateralis at rest before and after treatment. Subjects performed 3 bouts of 30 maximal knee extensions and flexions at 180 degrees /s with 1 minute of recovery between bouts before and after treatment. MAIN OUTCOME MEASURES: Intramuscular total creatine, phosphocreatine, free creatine, and total work output. RESULTS: Creatine ingestion did not significantly elevate intramuscular total creatine, phosphocreatine, or free creatine or improve total work production. CONCLUSION: Creatine ingestion had no significant effect on muscle creatine stores or high-intensity exercise capacity in individuals with MS. 相似文献
83.
Granulocyte (PMN) concentrates collected for transfusion to septic, neutropenic patients are stored in the blood bank for various periods of time before they are given. Current methods of blood bank storage of PMN concentrates are associated with impaired in vitro PMN chemotaxis (CTX) and in vivo recovery and circulation kinetics after 24 hours of storage. This suggested the possibility that PMN may become hyperadherent during storage. To test this hypothesis, PMN concentrates were harvested and stored at both 22 and 6 degrees C and their adherence properties to relevant biologic surfaces, endothelial cell (EC) monolayers, and extracellular matrix (ECM) derived from endothelium were measured. Adherence was measured within 4 hours of collection and after 24 and 48 hours of storage. The aggregation properties of fresh and stored PMN were also studied. The adherence of fresh, unstimulated PMN to EC and ECM (31 +/- 5% and 34 +/- 4%, respectively) increased significantly after storage for 24 hours (EC = 41 +/- 8%; ECM = 43 +/- 4%) at 22 degrees C. F-Met-Leu-Phe (FMLP) stimulated the adherence of fresh PMN (EC = 37 +/- 4%; ECM = 42 +/- 4%; p less than 0.05). The adherence of PMN stored at 22 degrees C was further stimulated by FMLP (EC = 46 +/- 6%; ECM = 50 +/- 4%). PMN stored at 6 degrees C had significantly higher adherence than PMN stored at 22 degrees C, and the percentage of increase in adherence induced by FMLP was attenuated in PMN stored at 6 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
84.
Dr. med. Axel Meissner Martin Christ Petra Maagh Rolf Borchard Marc van Bracht Ingo Wickenbrock Hans-Joachim Trappe Gunnar Plehn 《Clinical research in cardiology》2007,96(11):794-802
Objectives
The ablation
of common type atrial flutter
is mainly performed by two approved
techniques, whose efficacy
and outcome in terms of quality of
life have not been evaluated so far
in a long-term follow-up study
over years. A high proportion of
patients suffer from coexistent
atrial fibrillation, which may
worsen the ablation result. The
question arises whether one technique
is more effective than the
other when immediate ablation
results, the occurrence of atrial
fibrillation and the quality of life
are compared. Considering these
facts, it is reasonable to think
about new ablation strategies for
common type atrial flutter in the
era of new concepts in catheter
ablation of atrial fibrillation.
Methods
In a retrospective study
we evaluated a detailed questionnaire
in 132 patients who underwent
ablation of common type
between 1999 and 2004. Radiofrequency
ablation was performed
irrespective of coexistent atrial fibrillation
either with an irrigated
tip or the 8 mm tip electrode.
Acute and long-term ablation outcome,
and the associated quality of
life, pre-, under- and post-ablation
was compared in the two different
ablation groups. Recurrent tachycardia
were re-evaluated by 12 lead
ECG analysis and assessed for
both ablation groups.
Results
88
(67%) of the 132 patients contacted
answered the questionnaire
polling the perceived benefits of
the procedure. Of the other 44
patients (33%); 4 (3%) had died,
7 (5.3%) had moved, 33 patients
(25%) could not be included due
to missing or incoherent answers.
Independent of the ablation technique
there was a high acute and
long-term ablation success rate at
about 95%. After a mean of 3 years
of follow-up this benefit persists in
spite of a high proportion of recurrent
tachycardia, mainly atrial
fibrillation (55/88 patients, 59.1%).
Despite the occurrence of secondary
tachycardia, there was a high
significant long-term symptomatic
benefit in the state of healthy and
daily practice work, evaluated with
a p-value of < 0.0005. The frequency
of episodes and the symptom
"tachycardia" were significantly
reduced after effective ablation
of common type atrial flutter,
p-values of 0.003 and 0.002,
respectively.
Therefore the need for hospitalization
was significant reduced
(p = 0.001). Comparison of both
approaches revealed that there
was no significant difference related
to the incidence and occurrence
of atrial fibrillation.
Conclusions
The two mainly accepted
and applied techniques for the
ablation of common type atrial
flutter show an excellent outcome
under the aspect of ablation efficacy
and quality of life in longterm
follow-up. Three years after
the ablation procedure the majority
of patients consider the intervention
beneficial. Despite the
relatively high appearance of atrial
fibrillation in the long-term
follow-up this effect is still traceable. 相似文献
85.
We studied clinical features potentially related to dysphagia and three
indices from a timed test of swallowing--average volume per swallow (ml),
average time (s) per swallow and swallowing capacity (ml/s)--in 181
screened healthy adults and 30 patients with motor neurone disease (MND).
In healthy adults, age, sex and height accounted for 44.3% and 55.6% of the
variance of log average volume per swallow and log swallowing capacity,
respectively. Symptoms and signs were more prevalent in the MND group and
were associated with reduced swallowing capacity and reduced average volume
per swallow; repeatability studies on these two indices in both groups
showed that the median difference between the mean of two recordings on
successive days and the mean of all recordings (6-15 over 3 days) was <
5% (maximum third quartile 12.8%, indices expressed as percent predicted
according to age and sex). Using this simple bedside test, swallowing
function can be quantified on a ratio scale and expressed as percent of
that predicted by age and sex; such information may improve the predictive
value of clinical assessment and provides a practical way of monitoring
change in patients with dysphagia.
相似文献
86.
KAZUYOSHI SUENARI M.D. YU‐FENG HU M.D. HSUAN‐MING TSAO M.D. CHING‐TAI TAI M.D. CHERN‐EN CHIANG M.D. YENN‐JIANG LIN M.D. SHIH‐LIN CHANG M.D. LI‐WEI LO M.D. TUAN TA‐CHUAN M.D. PI‐CHANG LEE M.D. NGUYEN HUU TUNG M.D. SHIH‐YU HUANG M.D. TSU‐JUEY WU M.D. SHIH‐ANN CHEN M.D. 《Journal of cardiovascular electrophysiology》2010,21(10):1114-1119
Gender Differences in Patients With AVNRT. Introduction: The detailed electrophysiological characteristics of the gender differences associated with atrioventricular nodal reentrant tachycardia (AVNRT) have not been clarified. This study investigated the gender‐related electrophysiological differences in a large series of patients undergoing radiofrequency catheter ablation. Methods and Results: A total of 2,088 consecutive AVNRT patients (men/women 869/1,219) who underwent catheter ablation were enrolled in this study. We evaluated the gender differences in their electrophysiological characteristics. Women had a significantly younger age of onset, higher incidence of multiple jumps, shorter AH interval, atrial effective refractory period (ERP), anterograde fast pathway ERP, anterograde slow pathway ERP, and retrograde slow pathway ERP, and longer ventricular ERP than men. The incidence of baseline ventriculoatrial dissociation was lower in women than in men. Women needed less isoproterenol/atropine to induce AVNRT. No gender differences in the radiation exposure time, procedure time, complication rate, acute success rate, or second procedure rate were noted. Both typical and atypical AVNRT were more predominant in women. In the patients with atypical AVNRT, there was no significant gender difference in incidence of baseline ventriculoatrial dissociation; however, the retrograde slow pathway ERP was significantly shorter in women than in men. Women of premenopausal age (≤50 years old) had a significantly higher incidence of anterograde multiple jumps and a retrograde jump phenomenon, and a shorter anterograde slow pathway ERP and retrograde slow pathway ERP than those of women over 50 years old. Conclusion: Gender differences in the anterograde and retrograde AV nodal electrophysiology were noted in the patients with AVNRT. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1114‐1119) 相似文献
87.
LI‐WEI LO M.D. SATOSHI HIGA M.D. Ph.D. YENN‐JIANG LIN M.D. SHIH‐LIN CHANG M.D. TA‐CHUAN TUAN M.D. YU‐FENG HU M.D. WEN‐CHIN TSAI M.D. HSUAN‐MING TSAO M.D. CHING‐TAI TAI M.D. SUGAKO ISHIGAKI M.D. ASUKA OYAKAWA M.D. MINETAKA MAEDA M.D. KAZUYOSHI SUENARI M.D. SHIH‐ANN CHEN M.D. 《Journal of cardiovascular electrophysiology》2010,21(6):640-648
Unipolar Characteristics of CFAEs. Background: The noncontact mapping (NCM) system possesses the merit of global endocardial recording for unipolar and activation mapping. Objective: We aimed to evaluate the unipolar electrogram characteristics and activation pattern over the bipolar complex fractionated atrial electrogram (CFAE) sites during atrial fibrillation (AF). Methods: Twenty patients (age 55 ± 11 years old, 15 males) who underwent NCM and ablation of AF (paroxysmal/persistent = 13/7) were included. Both contact bipolar (32–300 Hz) and NCM virtual unipolar electrograms (0.5–300 Hz) were simultaneously recorded along with the activation pattern (total 223 sites, 11 ± 4 sites/patient). A CFAE was defined as a mean bipolar cycle length of ≤ 120 ms with an intervening isoelectric interval of more than 50 ms (Group 1A, n = 63, rapid repetitive CFAEs) or continuous fractionated activity (Group 1B, n = 59, continuous fractionated CFAEs), measured over a 7.2‐second duration. Group 2 consisted of those with a bipolar cycle length of more than 120 ms (n = 101). Results: The Group 1A CFAE sites exhibited a shorter unipolar electrogram cycle length (129 ± 11 vs 164 ± 20 ms, P < 0.001), and higher percentage of an S‐wave predominant pattern (QS or rS wave, 63 ± 13% vs 35 ± 13%, P < 0.001) than the Group 2 non‐CFAE sites. There was a linear correlation between the bipolar and unipolar cycle lengths (P < 0.001, R = 0.87). Most of the Group 1A CFAEs were located over arrhythmogenic pulmonary vein ostia or nonpulmonary vein ectopy with repetitive activations from those ectopies (62%) or the pivot points of the turning wavefronts (21%), whereas the Group 1B CFAEs exhibited a passive activation (44%) or slow conduction (31%). Conclusions: The bipolar repetitive and continuous fractionated CFAEs represented different activation patterns. The former was associated with an S wave predominant unipolar morphology which may represent an important focus for maintaining AF. (J Cardiovasc Electrophysiol, Vol. 21, pp. 640‐648, June 2010) 相似文献
88.
目的:研究野茼蒿的挥发性成分。方法:用固相微萃取(solid-phase microextrations,SPME)和气相色谱-质谱(gas chromatography-mass spectrometry,GC-MS)联用仪对野茼蒿的挥发性成分进行测定。结果:从中共鉴定出37种化学成分。含量最多的3种成分是月桂烯(61.609%)、牛儿烯D(6.481%)、α-葎草烯(6.293%)。结论:茼蒿主要挥发性成分为烯烃。 相似文献
89.
90.
Concurrent exercise and muscle protein synthesis: implications for exercise countermeasures in space
Carrithers JA Carroll CC Coker RH Sullivan DH Trappe TA 《Aviation, space, and environmental medicine》2007,78(5):457-462
INTRODUCTION: Exercise countermeasures for long duration space crews incorporate aerobic and resistance exercise (i.e., concurrent training). Microgravity simulation studies show that resistance exercise alone can be completely effective at preventing muscle loss, yet crews return from missions with reduced muscle mass and function. Some Earth-based studies show human skeletal muscle size and strength increases typically noted with resistance training are blunted when aerobic and resistance training are performed concurrently. The purpose of this study was to determine if the addition of aerobic exercise prior to performing resistance exercise blunts the acute anabolic response to resistance exercise. METHODS: Myofibrillar protein synthesis rates were determined in 12 individuals (6 men, 6 women, 26 +/- 2 yr) by measuring the incorporation of [2H5]phenylalanine into vastus lateralis muscle protein following resistance exercise (4 sets of 10 repetitions of both leg press and leg extension) and following resistance exercise that had been preceded by 90 min of strenuous aerobic cycling exercise. RESULTS: Myofibrillar protein synthesis following resistance exercise (0.092 +/- 0.006% x h(-1)) was not suppressed (p > 0.05) compared with following concurrent exercise (0.100 +/- 0.007% x h(-1)). DISCUSSION: It appears the anabolic response to resistance exercise cannot explain the attenuated muscle mass and strength gains imposed by chronic concurrent aerobic and resistance training, nor the response of space crews to in-flight concurrent countermeasures. These findings have important implications for future optimization of the concurrent aerobic and resistance exercise countermeasures for long duration space crews. 相似文献