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51.
Gm allotypes in blacks with systemic lupus erythematosus 总被引:3,自引:0,他引:3
J A Fedrick J P Pandey Z Chen H H Fudenberg S K Ainsworth R L Dobson 《Human immunology》1983,8(2):177-181
Serum samples were collected from 328 healthy American Blacks and from 61 American Blacks with systemic lupus erythematosus (SLE). Sera were typed for the Gm1,2,3,5,6,13,17, and 21 allotypes as well as for the Km(1) allotype. The frequency of Gm phenotype 1,17;5,6,13 was significantly increased in the SLE patients (p = 0.0001, RR = 3.19, EF = 0.29). Our data suggest the existence of at least two immunoglobulin allotype associated genes that somehow interact to increase susceptibility to SLE in Blacks. To our knowledge, this is the first report of an association of Gm and SLE in Blacks. 相似文献
52.
Nadine Clause Eduardo Ludwig Fernando Narro Jorge P. Ribeiro 《European journal of applied physiology》1993,67(3):222-225
Summary During incremental exercise, the left ventricular ejection fraction increases up to the intensity of the anaerobic threshold and tends to level off at higher exercise intensities. Since there is a correlation between the response of peak filling rate and ejection fraction to exercise, this study was conducted to determine whether the response of left ventricular diastolic function is similar to the response of systolic function relative to lactate threshold. Twelve healthy men performed two exercise tests on a cycle ergometer. In the first test, lactate threshold and maximal power output were determined. In the second exercise test, gated radionuclide ventriculography was performed at rest, at the lactate threshold intensity, and at peak exercise to measure ejection fraction and peak filling rate. Ejection fraction increased significantly from rest [mean (SD): 62 (5)%] to lactate threshold [76 (7) %] and did not change significantly from lactate threshold to peak exercise [77 (7)%]. Likewise, peak filling rate (normalized for stroke counts) increased from resting [6.1 (0.9)V
s · s–1] to lactate threshold [9.4 (1.8)V
s · s–1] and did not change significantly from lactate threshold to peak exercise [9.6 (2.9)V
s · s–1]. There was no correlation between the change in peak filling rate and the change in ejection fraction from rest to lactate threshold. Thus, during incremental exercise, left ventricular diastolic function responds qualitatively similar to systolic function. 相似文献
53.
To investigate airway physiology by use of inhaled aerosols, it is frequently necessary to measure the actual amount of material deposited on the airway wall as well as the site of particle deposition. To satisfy these needs, radiolabeled aerosols and gamma camera techniques have been used to measure regional deposition of inhaled particles. To make quantitative measurements of the amount deposited, previous investigators have used a "phantom" technique to indirectly calibrate the gamma camera for the attenuation of gamma rays through the lungs and chest wall. For this calibration, the phantom is a simulated lung containing a known amount of radioactivity. Radioactive counts emitted from the phantom are assumed to be attenuated in the same manner as the intact human lung. The present article describes a technique to determine directly the amount of inhaled aerosol deposited in the lung and simultaneously to calibrate the gamma camera for each individual subject. We used right angle light scattering and a gamma camera to measure individual values of the deposition fraction (DF) of inhaled aerosol deposited in the lung and the coefficient of attenuation (AC) of gamma rays in normal and obstructed lungs of human subjects. Radiolabeled monodisperse aerosols 1 and 2 microns in diameter were used. Knowledge of the activity of the inhaled aerosol (microcurie per liter), the volume inhaled, and the measured DF determined each subject's AC (counts per minute per microcurie). DF varied by an order of magnitude in normal (0.04 to 0.48) and obstructed (0.16 to 0.75) of subjects.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
54.
目的 比较改良的尖头梅花针与带锁髓内针治疗胫腓骨干骨折的临床综合疗效 ,正确选取内固定物。方法 分别用改良的尖头梅花针与带锁髓内钉内固定治疗胫腓骨干骨折 74例 ,比较两组的综合疗效。结果 改良梅花针组 48例 ,轻度外旋畸形 2例 ,无骨不愈合 ,平均骨折愈合时间 3.5个月 ,平均手术时间 40 mim ,住院费用 30 0 0元 (人民币 ) ,优良率93.75 % ;带锁髓内钉组 2 1例 ,发生骨延期愈合 2例 ,平均骨折愈合时间 5个月 ,平均手术时间 6 0 mim ,住院费用 5 5 0 0元(人民币 ) ,优良率 95 .2 4%。除胫骨远端下 1/ 3或严重的粉碎性骨折外 ,两组疗效无明显差异 (P >0 .0 5 )。结论 改良尖梅花针内固定操作简单、价格低廉、疗效确切 ,仍有较高的临床使用价值 ;带锁髓内钉能满足胫骨各种类型的骨折 ,扩大了髓内固定的适应症 ,随着成本的降低 ,已逐渐成为治疗胫腓骨骨折髓内固定的方向。 相似文献
55.
中华眼镜蛇毒F组分对沙鼠脑缺血再灌注损伤的保护作用 总被引:1,自引:1,他引:0
目的:研究中华眼镜它毒F组分脑缺血再灌注损伤的保护作用,方法:结扎沙鼠双侧颈总动脉1h,造成前脑缺血模型,用比色法测定脑匀浆过氧化脂质的最终产物丙二醛(MDA)的含量及超氧化物歧化酶(SOD)的活性,结果:F组分0.9,0.3,0.1mg/kg可显著抑制脑内脂质过氧化,降低MDA的含量,并提高超化物歧化酶的活,性且呈一定的量效关系,同缺血再灌组比较P<0.05,同阳性对照药尼莫通比较,P>0.05,结论:中华眼镜蛇毒F组分对脑缺血再灌注损伤有保护作用,可能与抑制自由基的生成和促进自由基的清除有关。 相似文献
56.
以Maxwell-Bonnel图拟合式、对比态Antoine方程及Pitzer-Riedel关联式分别求算饱和蒸汽压P^0,并用RoultK值(K=P^0/P),计算窄留分K值。根据实测的中原、孤岛和克拉玛依石油馏分低压K值,考察上述三式,结果表明:对比态Antoine式预测精度是最好的,其温度预测绝对平均偏差为7.0℃,K值预测平均相对偏差为15.6%,其他两模型偏差均较大。 相似文献
57.
58.
Heart failure (HF) and coronary insufficiency are common amongst surgical and critical care patients. Both are chronic conditions interrupted by acute episodes. HF activates neurohormonal mechanisms that worsen renal and cardiac function. Acute heart failure (AHF) commonly presents with dyspnoea as a consequence of systolic and/or diastolic dysfunction. Goals of treatment are symptom relief to maintain tissue perfusion and optimize cardiac function. Diuretics and vasodilators are used early; positive inotropic drugs are reserved for when other treatment has failed. Chronic heart failure (CHF) is treated using changes in lifestyle and drugs to manage symptoms. ACE inhibitors and beta-blockers are effective in systolic heart failure and are associated with improved mortality. HF with preserved ejection fraction (HFPEF) is less responsive to drug therapy, though outcomes are better than for systolic HF. Coronary insufficiency occurs because of an imbalance of myocardial oxygen balance, leading to symptoms of ischaemic heart disease (IHD). Treatment goals are maintaining coronary blood flow and reducing myocardial oxygen demand. Beta-blockers and anti-platelet drugs improve outcomes; modern anti-platelets are more effective but are associated with risks of haemorrhage. Statins are effective for primary and secondary prevention of myocardial infarction; they have additional anti-inflammatory properties. 相似文献
59.
60.
目的了解2011年与2017年南京25岁及以上人群归因于豆类摄入不足的缺血性心脏病(IHD)疾病负担和期望寿命损失情况,为IHD的饮食防控策略提供数据支撑。方法本研究资料来源于2011年和2017年南京市慢性病及其危险因素监测、南京市死因监测和2017全球疾病负担(GBD)资料,采用GBD团队提供的Excel插件程序计算人群归因分值(PAF),估算豆类摄入不足导致的IHD死亡和寿命损失。使用SPSS 20.0软件进行t检验。结果2017年,南京市因豆类摄入不足导致IHD的死亡例数占IHD总死亡例数的13.73%,较2011年(12.44%)增长了10.37%。2017年南京市归因于豆类摄入不足的IHD死亡例数和过早死亡损失寿命年(YLL)分别为645例、8116人年,较2011年(449例、6610人年)分别上升43.65%、22.78%;而标化归因死亡率和标化YLL率分别由2011年的11.05/10万、155.72/10万下降至2017年的8.86/10万、118.66/10万,下降率分别为19.82%、23.80%。2017年,豆类摄入不足导致的IHD死亡使期望寿命损失0.17岁,男性、女性分别损失0.13、0.21岁;与2011年相比,2017年男性、女性及总人群归因于豆类摄入不足的期望寿命损失均上升。结论豆类摄入不足已成为影响南京市居民死亡和期望寿命的饮食危险因素之一,应积极倡导合理膳食,增加居民豆类摄入水平,从而减少心血管疾病负担。 相似文献