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991.
Prevalence of Babesia antibody in a selected blood donor population   总被引:6,自引:0,他引:6  
Human babesiosis, a parasitic disease transmitted by the tick, Ixodes dammini, was confined previously to limited areas of the northeastern United States. It is a rare but potentially life-threatening complication of transfusion. Red cells and platelets prepared from asymptomatic donors have been implicated in transfusion-transmitted cases. More cases of babesiosis are being reported as the range of the vector expands in the United States. Blood donors from an endemic area were tested for antibody to Babesia microti during the summer. Only 3.7 percent of the 779 donors were seropositive, compared with 4.7 percent (p greater than 0.05) of donors from a nonendemic area. An epidemiologic survey of seropositive and matched seronegative controls demonstrated no significant differences that would assist in screening donors.  相似文献   
992.
目的 探讨利多卡因对脓毒症大鼠肺组织高迁移率族蛋白B1( HMGB1) mRNA表达的影响.方法 雄性Wistar大鼠50只,体重200 ~ 250 g,采用随机数字表法,将其随机分为5组(n=10):假手术组(S组)、脓毒症组(L组)、低、中和高剂量利多卡因组(LL1组、LL2组和LL3组).除S组外,其他4组采用盲肠结扎穿孔术制备大鼠脓毒症诱发急性肺损伤模型.LL1组、LL2组和LL3组分别于术毕、术后1、2h时腹腔注射利多卡因5、10、20 mg/kg,S组和L组给予等容量生理盐水.分别于术后24、48 h时处死5只大鼠,取肺组织,测定HMGB1 mRNA表达、髓过氧化物酶(MPO)活性和NF-κB活性,光镜下观察肺组织病理学结果.结果 与S组比较,其他4组肺组织HMGB1 mRNA表达上调,MPO活性升高(P<0.05);与L组比较,LL1组、LL2组和LL3组肺组织HMGB1 mRNA表达下调,MPO活性降低(P<0.01);LL1组、LL2组和LL3组肺组织HMGB1 mRNA表达依次下调,MPO活性依次降低(P<0.05).LL1组、屿LL2和LL3组肺组织NF-κB活性逐渐降低,肺组织损伤程度逐渐减轻.结论 利多卡因减轻脓毒症大鼠急性肺损伤的机制与下调肺组织HMGB1基因表达有关,其下调HMGB1基因表达的机制与抑制NF-κB活化有关.  相似文献   
993.
Almaguer‐Mederosa LE, Falcón NS, Almira YR, Zaldivar YG, Almarales DC, Góngora EM, Herrera MP, Batallán KE, Armiñán RR, Manresa MV, Cruz GS, Laffita‐Mesa J, Cyuz TM, Chang V, Auburger G, Gispert S, Pérez LV. Estimation of the age at onset in spinocerebellar ataxia type 2 Cuban patients by survival analysis. Previous studies have investigated the close association that exists between CAG repeat number and the age at onset in SCA2 = spinocerebellar ataxia type 2. These studies have focused on affected individuals. To further characterize this association and estimate the risk of a carrier developing SCA2 at a particular age as a function of a specific CAG repeat size, we have analyzed a large group of 924 individuals, including 394 presymptomatic and 530 affected individuals with a CAG repeat length of 32–79 units. Using a Kaplan–Meier survival analysis, we obtained cumulative probability curves for disease manifestation at a particular age for each CAG repeat length in the 34–45 range. These curves were significantly different (p < 0.001) and showed small overlap. All these information may be very valuable in predictive‐testing programs, in the planning of studies for the identification of other genetic and environmental factors as modifiers of age at onset, and in the design of clinical trials for people at enlarged risk for SCA2.  相似文献   
994.
The objective of this study was to determine the effect of laparoscopic sleeve gastrectomy (LSG) on blood pressure in private practice settings. This study involved a retrospective review of 870 consecutive adult patients >18 y of age who underwent LSG over a period of 12 mo in a private bariatric surgery center. Data were collected from the preoperative and postoperative follow-up visits at 1, 3, 6, and 12 mo. The study population consists of 694 hypertensive and 176 normotensive patients. From the baseline to 12 mo after LSG, (1) mean body weight/body mass index decreased from 123 kg/44 kg/m2 to 94 kg/34 kg/m2 (P < .001); (2) mean systolic/diastolic blood pressure in hypertensive patients decreased from 131.9/79.9 to 127.6/77.1 mm Hg (P < .001); 3) only mean systolic blood pressure decreased in normotensive patients from 117.5 to 114.0 mm Hg (P < .001). One month after LSG, mean systolic blood pressure had decreased from 131.9 to 126.2 mm Hg (P < 0. 001) and the average number of antihypertensive medications per patient declined from 1.5 at the baseline to 0.6 (P < .001). Over the following 11 mo, blood pressure remained stable despite reduced antihypertensive therapy. Patients requiring more than two antihypertensive agents fell from 49% at the baseline to 22% at 12 mo. Hypertension resolved in 34% of patients. Linear regression analysis showed no association between change in body weight and change in systolic blood pressure. Within 1 mo of LSG, hypertensive patients experienced a significant decline in systolic blood pressure and antihypertensive therapy that remains unchanged at 12 mo in the face of major reductions in antihypertensive medications. Weight loss and blood pressure reduction may not be directly related.  相似文献   
995.
996.
甘草饮片标准汤剂的研究   总被引:1,自引:0,他引:1  
制备了15批不同产地的甘草饮片标准汤剂,对甘草苷和甘草酸进行含量测定,计算转移率与出膏率,并建立了HPLC指纹图谱分析方法。通过对15批甘草饮片标准汤剂进行测定,甘草苷和甘草酸转移率范围分别为59.4%~87.4%和49.8%~78.9%,出膏率范围为29.9%~38.9%,并用中药色谱指纹图谱相似度评价系统(2012A)软件进行指纹图谱分析,确定了10个共有峰,对15批甘草饮片标准汤剂分别进行了相似度评价,其相似度均大于0.9。该研究中甘草饮片标准汤剂制备方法规范,15批样品质量稳定,指纹图谱相似度高,其方法精密度、稳定性和重复性良好,可为甘草配方颗粒的质量控制提供参考。  相似文献   
997.
998.
We have studied five pigs undergoing bilateral clamping of therenal pedicles, seven pigs undergoing orthotopic liver transplantationand three control animals without surgery in order to examinethe roles of the kidney and liver in the plasma clearance ofpipecuronium. An i.v. infusion of pipecuronium was controlledto maintain a constant 90–95 % twitch depression throughoutthe investigation. The right sciatic nerve was stimulated continuouslywith supra-maximal stimuli at 0.1 Hz and the force of the correspondingevoked isometric muscle contraction was recorded continuously.Control pigs needed an infusion rate of pipecuronium 8–10.7µg kg–1 min–1. In the renal group, it wasnecessary to reduce the infusion rate of pipecuronium by about25% after clamping both renal vascular pedicles (P < 0.05compared with controls); in pigs undergoing liver transplantation,it was necessary to reduce the rate by approximately 80% afterclamping hepatic vessels (P < 0.05 compared with controlsand from the period after clamping of renal vessels). Afterhepatic recirculation, the infusion rate of pipecuronium wasincreased progressively to a rate which corresponded to 50%of baseline values (P < 0.05 compared with the anhepaticphase and from controls). Plasma concentrations of pipecuroniumwere comparable in the three animal groups and did not changesignificantly during the study. These data suggest that theliver plays a more important role than the kidney in the plasmaclearance of pipecuronium in pigs.  相似文献   
999.
An autologous fibrinogen-based adhesive for use in otologic surgery   总被引:1,自引:0,他引:1  
Successful middle ear surgery requires the availability of a safe, effective bonding material. Side effects caused by synthetic materials have led to the use of biologic adhesives; however, they carry the risk of transmission of infectious disease if they are prepared from pooled human blood. A procedure for the production of an autologous fibrinogen-based adhesive using polyethylene glycol to precipitate the fibrinogen-factor XIII component from plasma is described. This procedure requires 40 ml of whole blood and approximately 3 hours' preparation time, and it can be performed in any blood bank with the facilities for sterile techniques. This adhesive has been used successfully for otologic surgery in 12 patients, and further study of the use of this biologic adhesive for other microsurgical techniques should be undertaken.  相似文献   
1000.
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