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61.
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
62.
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
63.
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
64.
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
65.
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
66.
67.
目的:探讨链脲佐菌素(STZ)建立妊娠期糖尿病(GDM)大鼠模型中不同给药剂量对模型稳定性的影响,研究GDM对母体及胎儿的影响率、转阴率和死亡率.方法:将46只SD孕鼠随机分为STZ低、中、高不同剂量组,分别一次性腹腔注射STZ35,45,60mg/kg;对照组腹腔注射等量的柠檬酸缓冲液.于妊娠第3,9,14,19d时测空腹血糖,并观察成模孕鼠在妊娠中体质量、饮水量、摄食量和尿量变化,比较孕鼠成模情况.结果:STZ45mg/kg组孕鼠在用药后出现明显的“三多一少”症状,其成模率83.3%为最高,转阴率最低.空腹血糖值STZ45mg/kg组(21.8±3.0)mmol/L与对照组(5.9±1.2)mmol/L相比较,其高血糖状态持续时间长,最稳定,且体质量也明显降低,差异具有统计学意义(P〈0.05).结论:STZ45mg/kg腹腔注射给药是建立GDM大鼠模型的最佳剂量,具有较好的稳定性. 相似文献
68.
Janice V. Bowie Hee-Soon Juon Lisa C. Dubay Lydie A. Lebrun Barbara A. Curbow Roland J. Thorpe Thomas A. LaVeist 《Journal of urban health》2009,86(6):861-871
Low-income urban whites in the United States have largely gone unexamined in health disparities research. In this study, we
explored cancer prevention behaviors in this population. We compared data on whites with low socioeconomic status (SES) from
the 2003 Exploring Health Disparities in Integrated Communities Study in Southwest Baltimore, Maryland (EHDIC-SWB) with nationally
representative data for low SES white respondents from the 2003 National Health Interview Survey (NHIS). Rates for health
behaviors and health indicators for whites from the EHDIC-SWB study as compared to NHIS prevalence estimates were as follows:
current cigarette smoking, 59% (31% nationally); current regular drinking, 5% (5% nationally); overweight, 26% (32% nationally);
obesity, 30% (22% nationally); mammography in the past 2 years, 50% (57% nationally); Pap smear in the past 2 years, 64% (68%
nationally); screening for colon cancer in the past 2 years, 41% (30% nationally); and fair or poor self-reported health,
37% (22% nationally). Several cancer prevention behaviors and health indicators for white EHDIC-SWB respondents were far from
the Healthy People 2010 objectives. This study provides rare estimates of cancer-related health and health care measures in
an understudied population in the United States. Findings illustrate the need for further examination of health behaviors
in low SES white urban populations who may share health risks with their poor minority urban counterparts. 相似文献
69.
70.
Geoffrey C. Nguyen MD PhD Melissa Munsell MD Steven R. Brant MD Thomas A. LaVeist PhD 《JPEN. Journal of parenteral and enteral nutrition》2009,33(5):563-568
Background: Racial disparities have been described in the use of a diverse spectrum of surgical procedures. The objectives of this study are to determine whether disparities also exist for the use of parenteral nutrition (PN) in inflammatory bowel disease (IBD). Methods: The U.S. Nationwide Inpatient Sample between 1998 and 2003 is analyzed to determine PN use among IBD inpatients diagnosed with protein‐calorie malnutrition and assess whether use patterns differ by race and geographical region. Results: The proportion of African American IBD admissions with protein‐calorie malnutrition who receive PN is significantly lower than that in whites (19.9% vs 28.1%, P = .001), whereas there is no difference between Hispanics and non‐Hispanic whites. After adjustment for gender, comorbidity, health insurance status, geographic region, and median neighborhood income, African Americans remain less likely than whites to receive PN (odds ratio [OR] 0.67; 95% confidence interval [CI], 0.50–0.89), whereas the difference between Hispanics and non‐Hispanic whites is marginally significant (OR 0.65; 95% CI, 0.41–1.04). PN use varies geographically, with highest rates in the Northeast (44.3%) and lowest in the Midwest (17.3%). Uninsured patients are less than half as likely to receive PN as those with insurance (OR 0.46; 95% CI, 0.31–0.69). Compared with whites, Hispanics experience a longer time interval between admission and initiation of PN (3.5 vs 4.8 days, P = .02) and have higher rates of catheter‐related complications (5.1% vs 12.2%, P = .04). Conclusions: Among IBD inpatients with clinically diagnosable malnutrition, PN use is lower among African Americans compared with whites. The underlying mechanisms of these racial variations merit further investigation. 相似文献