可溶性转铁蛋白受体检测对非成年人缺铁性贫血的诊断价值

目的：探讨可溶性转铁蛋白受体（sTfR）对非成年人缺铁性贫血（IDA）的诊断价值及其与慢性病贫血（ACD）的鉴别诊断价值。方法 IDA 组26例,男12例,女14例,年龄1月至15．5岁;ACD 组33例,男17例,女16例,年龄2月至14．0岁;对照组30例,男15例,女15例,年龄1月至15．5岁。sTfR、铁蛋白（SF）检测方法为免疫比浊法,血清铁（SI）为亚铁嗪比色法。结果各组患儿的性别比例、年龄无显著性差异;ACD 组的 SI 均值介于 IDA 组和对照组之间;IDA 组的 SF 显著低于 ACD 组（P ＜0．001）和对照组（P ＜0．001）,而 sTfR 显著高于 ACD 组（P ＜0．001）和对照组（P ＜0．001）。sTfR 鉴别诊断 IDA 和 ACD 的截值为3．56 mg/L,其敏感性、特异性、阴性预测值、阳性预测值、准确性分别为95．12％、93．92％、94．11％、97．53％、95．50％。结论sTfR 对 IDA 具有较高的敏感性及特异性,有助于诊断 IDA 及鉴别诊断 ACD。     

Serum transferrin receptor assay in iron deficiency anaemia and anaemia of chronic disease in the elderly

The most common cause of anaemia in the elderly is anaemia of chronic disease (ACD). However, iron deficiency anaemia (IDA) may coexist, and can be difficult to diagnose. The serum transferrin receptor (sTfR) blood test may be a better indicator of iron status as it is not affected by inflammation nor by advancing age. We evaluated it in four groups (10 males, 10 females each): 'young' controls, 'elderly' controls, IDA and ACD. All patients in the IDA group had elevated sTfR levels (mean +/- SD 65.2 +/- 17.7 nmol/l). All 'young' controls had normal sTfR (22.3 +/- 7.3 nmol/l) and ferritin levels (92.7 +/- 61.1 micrograms/l). Although all subjects in the 'elderly' controls and ACD group had normal, and raised or normal serum ferritin, respectively (88 +/- 62.3 micrograms/l; 631.2 +/- 509.5 micrograms/l), three (15%) 'elderly' controls and four (20%) ACD patients had raised sTfR levels, suggesting depleted iron stores. Bone-marrow aspirates were available in 3/4 ACD patients with raised sTfR. Haemosiderin was absent in two. The sTfR blood test is comparable to serum ferritin in diagnosing IDA in the elderly but also seems capable of differentiating ACD from IDA. Its potential as a non-invasive test of iron status, especially in elderly anaemic patients, deserves further evaluation.     

Soluble transferrin receptor concentration is not superior to log ferritin for evaluating erythropoiesis in adolescents with iron deficiency anemia

BACKGROUND: This study investigated the associations of soluble transferrin receptor (sTfR), log ferritin, the ratio of sTfR to log ferritin (sTfR-F index), and the log of the ratio of sTfR to ferritin [log(sTfR/F)] vs. reticulocyte production during iron deficiency. METHODS: Fluorescent intensity of reticulocytes, immature reticulocyte fraction (IRF), reticulocyte maturity index (RMI), sTfR, and serum ferritin were measured in 149 adolescents. RESULTS: There were no significant differences in reticulocyte parameters between the iron deficiency anemia (IDA) subjects with sTfR> or =4.9 mg/l and those with sTfR<4.9 mg/l. However, IDA subjects with log ferritin <0.73 microg/l exhibited significantly higher mean values for IRF and RMI, compared to those with log ferritin > or =0.73 microg/l (2.75+/-1.36% vs. 1.45+/-1.01%, p<0.05; 2.76+/-1.31% vs. 1.46+/-1.09%, p<0.05). In the non-IDA group, reticulocytes averaged 0.97+/-0.31% in subjects with sTfR> or =2.1 mg/l, which were significantly above the values in those with sTfR<2.1 mg/l (0.72+/-0.16%, p=0.005), but no significant differences were observed in reticulocyte parameters between the subjects with log ferritin > or =1.35 microg/l and those with log ferritin <1.35 microg/l. Correlation coefficients of log ferritin vs. RMI (r=-0.41) were higher than those of sTfR, sTfR-F index, and log(sTfR/F) vs. RMI (r=0.24, r=0.30, and r=0.28, respectively) in IDA subjects. CONCLUSION: Reticulocytopoiesis is more closely associated with log ferritin value than with sTfR concentrations in IDA patients, although sTfR significantly reflects erythropoietic activity in non-IDA subjects.     

Increased levels of serum transferrin receptor and serum transferrin receptor/log ferritin ratios in men with prostate cancer and the implications for body-iron stores

The serum transferrin receptor (sTfR) is a sensitive indicator of iron-deficiency erythropoiesis that is not affected by inflammation. Concentrations of this molecule are inversely correlated with body-iron stores, and increased body-iron stores are associated with an increased risk of cancer of the liver and lungs. However, an association between iron status as assessed on the basis of sTfR and prostate cancer has not been previously investigated. We measured sTfR and serum ferritin by means of an enzyme immunoassay in 27 men with newly diagnosed, untreated prostate cancer and in 72 controls. Our study population ranged in age from 38 to 78 years. The mean serum ferritin concentration in men with prostate cancer was 44.8% lower than that in men without this tumor ( P < .05). In contrast, the mean values of sTfR and sTfR/log serum ferritin were 32% and 60% higher, respectively, in men with prostate cancer than in those without this tumor ( P < .05). Differences between groups persisted after we took into account inflammation (alpha 1-acid glycoprotein > 1 g/L, C-reactive protein > 10 mg/L; P < .05). Among the entire study population and among men without inflammation, a higher percentage of subjects (29%-31%) than of controls (14%-22%) had sTfR values greater than 8 mg/L, suggestive of iron-deficiency erythropoiesis ( P < .05). The odds ratios for men with prostate cancer to have sTfR values of less than 2.9 mg/L (suggestive of increased body-iron stores) was 0, compared with 1.745 to 3.65 for the same men to have sTfR values greater than 8 mg/L. sTfR was negatively correlated with log ferritin ( r = -.422, P < .05) but did not correlate with tissue inflammation, tumor stage, or acute-phase proteins. It appears that prostate cancer is not associated with increased body-iron stores.     

Determination of serum cystatin C: biological variation and reference values.

Human cystatin C is a low molecular weight protein which has been proposed as a better marker of glomerular filtration rate than creatinine. To be able to interpret results obtained in different patient populations it is necessary to define cystatin C reference values. We measured serum concentration of cystatin C in 1223 subjects using a particle-enhanced nephelometric assay. Subjects were aged 4 to 79 years and were selected among apparently healthy individuals who came to the Centre for Preventive Medicine in Vandoeuvre-Lès-Nancy, France. We observed a Gaussian distribution of cystatin C concentration in serum. We did not find any effect of age or gender in children, hormonal status in women (puberty, menopause, oral contraceptives or hormone replacement therapy) or alcohol intake. Cystatin C concentration was slightly lower in female than in male adults below the age of 60 years. Cystatin C levels significantly increased above the age of 60 in both males and females, probably due to physiological aging of renal function. No other significant differences were observed between males and females. Using multiple regression analysis, moderate correlations were observed between body mass index and cystatin C, and between smoking and cystatin C, but these were not biologically significant. According to the literature, only methylprednisolone and cyclosporin A increased and decreased cystatin C levels, respectively. The reference values for cystatin C obtained in a carefully selected population were 0.75+/-0.089 mg/l for children aged 4-19 years, 0.74+/-0.100 mg/l for males and 0.65+/-0.085 mg/l for females (aged 20-59 years), and 0.83+/-0.103 mg/l for older individuals (> or =60 years).     

沿海居民痛风及高尿酸血症流行特点的随机、分层、整群抽样调查

背景:近年来研究发现,高尿酸血症和痛风与糖尿病、冠心病、高血压及脑血管疾病的发生和发展关系密切。对其进行深入研究和早期干预,对上述疾病一级和二级预防均有重要意义。目的:明确山东沿海20岁以上居民高尿酸血症与痛风的患病情况及其影响因素。设计:随机、分层、整群抽样调查。单位:青岛大学医学院附属医院内分泌科。对象:调查范围为山东省沿海城市,包括青岛、日照、烟台、威海、东营。抽取年龄20～80岁本地常住(≥5年)居民,以家庭为单位的自然人群为调查对象。方法:采用随机、分层、整群抽样的方法,入户调查青岛、烟台、威海、日照、东营长住居民约5000人高尿酸血症与痛风的患病情况。采用Sysmexchemix-180型全自动生化分析仪测定血尿酸、血脂、血糖、血肌酐,试剂购自日本西斯美康公司,其中血尿酸批内和批间CV分别为1.77%和2.32%。尿酸值高于正常者,在第3天再次抽空腹血进行复查。率的比较采用χ2检验,两组间均数比较用t检验,多组间均数比较用方差分析,因变量与自变量的相关分析用logistic回归分析。主要观察指标:高尿酸血症患病率、血尿酸水平、高尿酸血症患者痛风发生率,以及高尿酸血症影响因素分析结果。结果:计划调查5500人,实调查5003人,应答率为90.96%,其中男性2395人(47.87%);女性2608人(52.13%)。①高尿酸血症的患病率13.19%,按照2000年山东人口标化率为13.27%;其中男性患病率高于女性(18.32%,8.56%,χ2=108.52,P<0.01),男性发病风险为女性2.5倍(OR=2.5)。痛风的患病率为1.14%,标化率为1.10%;其中男性患病率高于女性(1.94%,0.42%,χ2=30.38,P<0.01),男性发病风险为女性5.3倍(OR=5.3)。②正常人群男性血尿酸水平高于女性[(343.40±84.54),(258.90±70.90)μmol/L,t=48.03,P<0.01]。男性高尿酸血症患者血尿酸水平明显高于女性[(469.43±48.08),(399.73±104.91)μmol/L,t=11.70,P<0.01]。男性痛风患者血尿酸水平高于女性[(502.44±106.76),(403.48±52.72)μmol/L,t=2.07,P<0.05]。③高尿酸血症患者痛风的发生率为8.64%。④女性50岁以后高尿酸血症和痛风的患病率随年龄的增加而增高,70岁以上为高发年龄;而男性60岁以前随年龄的增加而增高,50～59岁为高发年龄段,60岁以后又随年龄的增加而增高。且女性高尿酸血症和痛风的平均年龄比男性分别晚7.5和8.5岁。⑤非条件logistic多元逐步回归分析显示饮酒频率、饮酒量、食贝类量及频率、尿素氮、血肌酐、三酰甘油、总胆固醇、体质量指数、腰臀比为男性高尿酸血症独立的危险因子,OR=1.016～30.217,95%CI(1.010～1.023)～(9.955～214.869);而高密度脂蛋白胆固醇和重体力劳动为保护因素,OR=0.492,95%CI0.339～0.713,OR=0.755,95%CI0.575～0.991。年龄、高血压、食贝类量、尿素氮、血肌酐、三酰甘油、腰臀比、轻体力活动为女性高尿酸血症独立的危险因子,OR=1.022～27.34,95%CI(1.006～1.040)～(9.955～214.869);同样高密度脂蛋白胆固醇为保护因素,OR=0.428,95%CI0.223～0.820。结论:①高尿酸血症和痛风患病率存在性别差异。②山东沿海居民高尿酸血症和痛风患病危险因素包括贝类等海产品高摄入、低体力活动、腹型肥胖、肾功能减退、代谢综合征有关,其中男性还与饮酒情况,女性还与年龄有关。③男性在各年龄段均是高尿酸血症和痛风患病的危险阶段,而女性则重点在50岁以后。     

High sensitivity C-reactive protein: biological variations and reference limits.

Serum C-reactive protein (CRP) concentration was determined for 3605 subjects using an immunonephelometric assay improved to provide greater sensitivity. Subjects were from 5 to 75 years old and belonging to 1003 nuclear families recruited from the Stanislas Cohort Study between January 1994 and August 1995. Sample values for CRP ranged from 0.17 mg/l to 100 mg/l. Geometric means (mean - SD; mean +/- SD) were in the 5-14 years old group 0.37 (0.17-1.07) mg/l, in the 15-28 years old group 0.47 (0.17-1.38) mg/l and in the 29-75 years old group 0.98 (0.34-2.85) mg/l. For women, the geometric means were 0.38 (0.17-1.10) mg/l, 0.62 (0.20-1.90) mg/l and 0.98 mg/l (0.31-3.13) mg/l respectively. The interindividual variability ranged from 138% to 759% among different age classes. Biological factors associated with CRP concentration variations were examined and accounted for 25% of the CRP variability in men and 40% in women. The main biological factors statistically associated with CRP concentration variations in men were: drugs, leukocyte count, body mass index, tobacco consumption, age, and in women: drugs, leukocyte count, age, body mass index and hemoglobin concentration. These factors were used to define the exclusion and partition criteria when obtaining the reference samples. Medians for reference values ranged from 0.20 to 0.68 mg/l in males and from 0.20 to 0.78 mg/l in women.     

Serum ferritin and iron status in 'healthy' elderly individuals

Iron status, including S-ferritin, S-iron, S-transferrin, transferrin saturation and haemoglobin, was assessed in 267 selected elderly subjects (128 male, 139 female) with a median age of 79 years (range 60-93 years) not suffering from diseases connected with inappropriately high S-ferritin. In both sexes, S-ferritin levels were practically constant over the examined age range. Males had a geometric mean ferritin of 75 micrograms/l and females a value of 60 micrograms/l (p less than 0.001). Levels of S-ferritin less than 15 micrograms/l (i.e. depleted iron stores) were found in 7.8% of males and in 10.1% of females. An S-ferritin level less than 15 micrograms/l and transferrin saturation less than 15% (i.e. latent iron deficiency) was observed in 2.3% of males and in 2.2% of females. None had iron deficiency anaemia. In subjects (n = 232) without iron deficiency [i.e. S-ferritin greater than or equal to 15 micrograms/l, mean red cell volume greater than or equal to 79 fl and haemoglobin greater than or equal to 121 g/l (7.5 mmol/l)], the arithmetic mean of S-iron was 18 mumol/l. S-transferrin 28 mumol/l and transferrin saturation 33%. The levels of S-iron, S-transferrin and transferrin saturation were not significantly different in males and females.     

The soluble transferrin receptor (sTfR)-ferritin index is a potential predictor of celiac disease in children with refractory iron deficiency anemia.

The soluble transferrin receptor (sTfR) distinguishes iron deficiency anemia from other types of anemia. Refractory iron deficiency anemia is often the onset symptom in malabsorption-induced celiac disease. We evaluated whether sTfR levels distinguish celiac disease-associated iron deficiency anemia from iron deficiency anemia of other origin. To this aim we measured sTfR and ferritin levels and their ratio (the sTfR/ferritin index) and other hematological parameters in 42 anemic children (20 with and 22 without celiac disease) vs. 22 non-anemic children with celiac disease and 31 healthy controls (age range 4-12 years). Hemoglobin parameters, mean cell volume, and serum iron and ferritin levels were decreased to a similar extent in the anemic patients (celiac and non-celiac). The sTfR level in non-anemic celiac patients was similar to that of normal controls (1.7+/-0.35 mg/L), whereas it was significantly increased in non-celiac and celiac anemic patients (2.2+/-0.5 mg/L, p<0.05 and 2.7+/-1.2 mg/L, p<0.001, respectively). The sTfR/ferritin index was also increased more in the anemic celiac patients (mean 4.4, range 1.5-12.0) than in anemic non-celiac children (mean 2.6, range 1.4-4.0) compared with non-anemic children (mean 1.2, range 0.7-2.0). Differences were more pronounced when ferritin was <5 ng/mL. Thus, the sTfR/ferritin index may be a predictive measure in discriminating anemic patients with celiac disease from those without celiac disease.     

外周血平均红细胞体积与年龄之间的关系探讨

目的探讨外周血红细胞体积与年龄变化的关系。方法采用SysmexXE．2100全自动血液分析仪对3,600名健康体检者进行平均红细胞体积（MCV）分析。将被检者分成4个年龄段：20岁以下、20～39岁、40-60岁、60岁以上,将不同年龄段的MCV进行μ检验处理。结果20岁以下的MCV〈20-39岁的MCV〈40-60岁的MCV〈60岁以上的MCV（P〈0．01）。结论MCV可能随着年龄的增加而增大。     

Hyperlipidemia in a general population: epidemiology

Serum total cholesterol levels were measured in a general population aged 40 years or older in Hisayama, Japan, and were compared among three cohorts, including 1,621 residents in 1961(1st cohort), 2,053 in 1974(2nd cohort) and 2,649 in 1988(3rd cohort). Dietary habits were determined by a direct interview in the randomly chosen study subjects in 1965, 1985 and 1994. Serum cholesterol levels greatly increased by approximately 30 mg/dl or more in males and females of all age groups from 1st to 2nd cohort, and further but less greatly increased by 20 mg/dl or less from 2nd to 3rd cohort. Prevalence of hypercholesterolemia (> or = 220 mg/dl) was more markedly increased nine-fold from 3% in 1961 to 28% in 1988 for males, and six-fold from 7% to 42% for females. During the follow-up period, lifestyle including dietary habits in Hisayama had been changed or westernized, namely more intake of animal fats and proteins and less intake of carbohydrate or rice without changes in total energy intake. Consequently, the frequency of hypercholesterolemia increased in recent years with more obesity and diabetes. Modifications of lifestyle are highly recommended for prevention of cardiovascular diseases.     

Effect of hemochromatosis genotype and lifestyle factors on iron and red cell indices in a community population

BACKGROUND: Heterozygotes for the C282Y mutation of the HFE gene may have altered hematology indices and higher iron stores than wild-type subjects. METHODS: We performed a cross-sectional analysis of 1488 females and 1522 males 20-79 years of age drawn from the Busselton (Australia) population study to assess the effects of HFE genotype, age, gender, and lifestyle on serum iron and hematology indices. RESULTS: Male C282Y heterozygotes had increased transferrin saturation compared with the wild-type genotype. Neither male nor female heterozygotes had significantly increased ferritin values compared with the wild-type genotype. Younger (20-29 years) wild-type males, but not heterozygous males, had significantly lower ferritin values than wild-type males in the older age groups. Compound heterozygous subjects had increased means for serum iron, transferrin saturation, corpuscular volume, and corpuscular hemoglobin compared with the wild-type genotype, and the males also had increased ferritin values (medians 323 vs 177 microg/L; P = 0.003). In both male and female wild-type subjects, an increased body mass index was associated with decreased serum iron and transferrin saturation and increased ferritin values. There was a significant increase in ferritin concentrations in both genders with increasing frequency of red meat consumption above a baseline of 1-2 times per week and alcohol intakes >10 g/day. CONCLUSIONS: Male C282Y heterozygotes had significantly increased transferrin saturation values. Compound heterozygous (C282Y/H63D) subjects formed a separate category of C282Y heterozygotes in whom both iron and red cell indices were significantly increased compared with the wild-type genotype.     

Absence of age and gender effects on the pharmacokinetics of a single 500-milligram oral dose of levofloxacin in healthy subjects.

The influence of age and gender on the pharmacokinetics of levofloxacin in healthy subjects receiving a single oral 500-mg dose of levofloxacin was investigated in this parallel design study. Six young males (aged 18 to 40 years), six elderly males (aged > or = 65 years), six young females (aged 18 to 40 years), and six elderly females (aged > or = 65 years) were enrolled and completed the study. The study reveals that the bioavailability (rate and extent) of levofloxacin was not affected by either age or gender. In both age (young and elderly) and gender (male and female) groups of subjects, peak concentrations in plasma were reached at approximately 1.5 h after dosing; renal clearance of levofloxacin accounted for approximately 77% of total body clearance, and approximately 76% of the administered dose was recovered unchanged in urine over the 36 h of collection. The apparent differences in the calculated pharmacokinetic parameters for levofloxacin between the age groups (young versus elderly) and between the gender groups (males versus females) could be explained by differences in renal function among the subjects. A single dose of 500 mg of levofloxacin administered orally to both young and old, male and female healthy subjects was found to be safe and well tolerated. As the differences in levofloxacin kinetics between the young and the elderly or the males and the females are limited and are mainly related to the renal function of the subjects, dose adjustment based on age or gender alone is not necessary.     

Reference intervals for thyroid hormones on the architect analyser.

The objective of this study was to establish reference intervals for thyroid stimulating hormone (TSH), free thyroxine (FT4), free triiodothyronine (FT3), total thyronine (TT4) and total triiodothyronine (TT3) on the Architect i2000 analyser (Abbott). Serum samples were obtained from apparently healthy adults (n=217, age 18-90 years) excluding individuals taking oral contraceptives or under hormone replacement therapy. The second group were ambulatory euthyroid patients (n=323) excluding those with a history of thyroid disorders. We also investigated thyroid hormones in sera from euthyroid hospitalised patients (n=490) excluding those with severe non-thyroidal illness. The reference intervals for the healthy adults were for TSH 0.17-4.23 mIU/l, for FT4 11.24-26.86 pmol/l, for FT3 2.56-6.36 pmol/l, for TT4 55.8-155.1 nmol/l and for TT3 0.90-2.54 nmol/l. TSH and TT3 concentrations were similar in males and females. However, FT4, FT3 and TT4 levels exhibited significant differences between females and males. No significant differences were observed between the concentrations of TSH, FT3, TT3, FT4 and TT4 in healthy subjects and in euthyroid ambulatory patients aged 18-90 years. TSH levels in healthy subjects were the same in younger and older individuals. In contrast, in outpatients and in hospitalised patients TSH concentrations were significantly lower (20%) in subjects older than 50 years compared to those younger than 50 years. For FT3 and TT3 we consistently observed in all three study groups 6-7% and 8-12% higher concentrations in the younger (< 50 years) compared to the older (> 50 years) subjects. For FT4 and TT4 no consistent pattern of correlation with age was detectable when the three study groups were analysed independently. The reference intervals for thyroid hormones determined in this study differ considerably from values found in other European and non-European countries. This underlines the need for population-specific reference ranges.     

三甲医院医务人员甲状腺超声特征分析

目的 了解医护人员健康体检时甲状腺结节和甲状腺弥漫性病变的检出率情况.方法 分析2020年9至11月在西部战区总医院体检中心进行健康体检的2634名医务人员的甲状腺超声检查结果,剔除既往有甲状腺手术史者23名,共2611名纳入研究,其中男性1109例,女性1502例,年龄为15～99岁,平均(39.6±17.0)岁.根...     

Soluble transferrin receptor in hemochromatosis patients during phlebotomy therapy

BACKGROUND: The monitoring of phlebotomies in hemochromatosis patients depends on iron status measured by ferritin and transferrin saturation (TS). However, in the presence of inflammation or liver injury, soluble transferrin receptor (sTfR) determination was proposed to replace ferritin for diagnosing iron deficiency (ID). The present study evaluated performances of sTfR for the prediction of iron deficiency in a large number of hemochromatosis patients under phlebotomy therapy. METHODS: We studied 52 patients undergoing therapeutic phlebotomies and obtained 2 samples from 37 patients. Biological parameters were determined before each phlebotomy began. Performances of sTfR and TS in the diagnosis of iron deficiency were compared, according to ferritin levels under 12 microg/l. RESULTS: Ferritin and TS were correlated with removed iron (r=0.473, p<0.005 and r=0.345, p<0.05, respectively) and sTfR was correlated with the decrease in hemoglobin levels induced by phlebotomies (r=-0.678, p<0.0001). Areas under Receiver Operating Characteristics (ROC) curves for sTfR and TS were not statistically different for prediction of iron deficiency and sensitivity/specificity of sTfR at 1.64 mg/l were 67/86%. CONCLUSIONS: sTfR determination could be used to predict iron depletion induced by phlebotomies when ferritin is of limited interest, to avoid the appearance of anemia.     

轻型珠蛋白生成障碍性贫血患者铁沉积状态的研究

目的了解轻型珠蛋白生成障碍性贫血(简称地贫)患者铁负荷的状态,为临床干预提供依据。方法选取经基因检测确诊的轻型地贫患者458例,分为α-地贫组及β-地贫组;以血常规正常的120例体检者为对照组。比较3组间血清铁、铁蛋白水平差异,分析铁蛋白与患者年龄、基因型别及血红蛋白的相关性。结果血清铁含量在3组间差异无统计学意义(P0.05),而血清铁蛋白在3组间差异有统计学意义(P0.05),且β-地贫组高于α-地贫组(P0.05);各年龄段之间铁蛋白水平存在明显差异(P0.05),且在小于或等于20岁及老年患者中水平较高;在大于20岁的患者中,铁蛋白水平与年龄存在一定程度的正相关;α-地贫组各基因型间血清铁蛋白水平比较,差异有统计学意义(P=0.006);β-地贫组血清铁蛋白与血红蛋白存在较弱的负相关(r=-0.252,P=0.001)。结论血清铁蛋白是评价地贫铁负荷的较敏感指标;血清铁蛋白在大于或等于20岁的患者中与年龄呈正相关;α-地贫与β-地贫患者铁负荷呈现不同的特征。     

Age and gender effects on ondansetron pharmacokinetics: evaluation of healthy aged volunteers.

Modest differences in the clearance of the 5HT3 antagonist, ondansetron, among different age groups were detected in two groups of healthy elderly volunteers, one group aged 61 to 74 years ("elderly") and the other 75 to 82 ("aged") years, in addition to young healthy subjects. Both a single 0.15 mg/kg intravenous dose and a single 8 mg oral dose were administered according to a randomized crossover design with a minimum 3-day washout period between treatments. Mean plasma clearance decreased (young, 0.349 L/hr/kg; elderly, 0.279 L/hr/kg; aged, 0.214 L/hr/kg; p less than 0.05) with increasing age. Volume of distribution at steady state was unaffected by age (young, 1.81 L/kg; elderly, 1.94 L/kg; aged, 1.71 L/kg), resulting in increases in mean plasma half-life (young, 3.4 hours; elderly, 4.5 hours; aged, 5.4 hours) and mean absolute bioavailability (young, 57%; elderly, 61%; aged, 69%) with increasing age. Female subjects cleared ondansetron more slowly than males (p less than 0.05), resulting in higher absolute bioavailability. Ondansetron was well tolerated by all age groups with no increase in the number of adverse events observed in older volunteers.     

Serum lipid concentrations and prevalence of dyslipidemia in a large professional population in Beijing

BACKGROUND: Lipid abnormalities are major risk factors for premature coronary artery diseases. We investigated serum lipids and the prevalence of dyslipidemia in a professional population in Beijing and compared these data with those obtained in a similar population during 1984-1986. METHODS: We studied 14 963 individuals 20-90 years of age. Health status was determined by questionnaires and physical check-ups. Total cholesterol (TC), LDL-cholesterol (LDL-C), HDL-cholesterol (HDL-C), and total triglycerides (TGs) were measured. TC >5.7 mmol/L, LDL-C >3.6 mmol/L, TGs >1.7 mmol/L, and HDL-C <0.9 mmol/L were defined as abnormal. RESULTS: Mean serum TC, LDL-C, and TG concentrations were increased compared with the values obtained in 1984-1986, with 52.7% of males and 42.9% of females having at least one abnormal lipid concentration. Hypercholesterolemia occurred in 6% of males and 2.8% of females in the younger group (20-39 years) and in 20.2% of males and 38.7% of females in the older group (>60 years). HDL-C was abnormally low in approximately 7% of males and in 1.6% of females. The prevalences of hypercholesterolemia, hypertriglyceridemia, and abnormally low HDL-C, especially the presence of slight hypertriglyceridemia, were higher than in 1984-1986 in all age groups. The increase was most prominent in the middle age group (40-59 years). CONCLUSIONS: Hypercholesterolemia, hypertriglyceridemia, and abnormally low HDL-C have increased considerably over the past 20 years in professional populations in Beijing. Dietary changes and less physical activity resulting from rapid improvements in living conditions may be the causes for the increases. Enhanced preventive measures should be undertaken to modify these situations.     

Serum alkaline DNase activity in normal or nonhospitalised individuals

According to previous observations, the variations in serum alkaline DNase activity (SADA) appeared to be useful in monitoring malignant disease. In this study, SADA was measured in 625 individuals to explore nontumor-related factors which may influence SADA levels. The overall range in SADA was 0.2-82.3 kU/l. Women aged 50-79 years had higher (p less than 0.001) levels of SADA than younger females. A similar but less consistent effect of age was noticed in men (0.01 less than p less than 0.05). Older men had lower (0.01 less than p less than 0.05) SADA levels than the older women. Old women substituted with estrogens had lower (0.01 less than p less than 0.05) levels of SADA than those not treated with estrogens. SADA levels in pregnancy as well as postparturition were lower (p less than 0.001) than SADA values in nonpregnant females of similar age. In fertile women, no SADA variation was observed during the menstrual cycle and there was no significant effect of contraceptive pills. In males, SADA seemed unrelated to testosterone or cortisol levels but varied during the day. Smoking, alcohol consumption and drug therapy appeared to be without effect on SADA.