《汤姆·索亚历险记》的现实主义与浪漫色彩

马克·吐温作品中的现实主义因素是不容质疑的 ,但他还兼容了其它创作手法 ,喜欢采用浪漫主义的笔调 ,以夸张的、荒诞的手法刻画人物性格。在《汤姆·索亚历险记》中 ,吐温一方面讽刺了镀金时代小市民的庸俗、保守、贪婪 ,资产阶级儿童教育的清规戒律以及道德和宗教的虚伪 ;另一方面描写了汤姆及其伙伴追求传奇、冒险、浪漫、幸福的生活。既赋于现实主义的真实写照 ,又寄予浪漫主义的大胆抒情。现实主义同理想浪漫主义水乳交融 ,这在很大程度上构成了这部小说的创作风格。     

青光眼治疗中的种族差异

由美国国家眼科研究所领导的一项研究发现,对两种青光眼手术治疗的反应有显著的种族差异。在一项长达7年有332名黑人及249名白人患者参加的多中心试验中,研究人员发现黑人患者对激光手术的反应较好,而对白人患者采用小梁切除术则效果较佳(Ｏｐｈｔｈａｌｍｏｌｏｇｙ1998;105:11356)。研究所所长ＣａｒｌＫｕｐｆｅｒ博士指出,这项研究首次揭示了对不同手术治疗的反应存在种族差异。结果提示,医生在对药物治疗失败的白人青光眼患者治疗时,宜选用小梁切除术而不是传统的激光手术。这项研究的本意是比较两种不同手术方案对进展性开角型青光眼…     

应用PCR／SSO方法分析湖南籍汉族人HLA－DR，DQ，DP的DNA多态性

采用ＰＣＲ／ＳＳＯ方法分析了６７例湖南籍汉族正常人中ＨＬＡ－ＤＲ，ＤＱ，ＤＰ位点共１０５个等位基因的分布情况。在６７例检出的７２个等位基因中，其部份频率明显不同于美国白人、黑人和巴西混血人种。提示湖南汉族人与美国白人、黑人和巴西混血人种间存在明显的种族差异。     

接受主动脉瓣置换术的黑人和白人老年患者的治疗差异

背景:大多数先前关于心脏治疗的种族差异的研究关注于不同医生和医院治疗方面的潜在差异。然而,不同实践模式医院采用不同方法也可能导致治疗差异。方法和结果:比较1999—2001年在904所美国医院接受主动脉瓣置换术的78154例黑人和白人患者中生物瓣膜(BPV)的应用,所有患者均为年龄≥65岁的医疗保险受益人。采用广义线性混合模型首先说明患者特征的差异,然后说明黑人和白人患者所住医院的差异。经患者特征校正后,BPV在黑人患者中的使用低于白人患者(RR0.93,95%CI0.91～0.95,P<0.001)。然而,黑人患者更易在BPV总使用率最低的医院进行手术…     

活体供肾者健康状况因种族而异

目前已知，糖尿病、高血压及慢性肾病在不同种族人群中的负担存在差异，但供肾者是否也是如此呢？研究人员采用美国某私人保险公司4650名供体的保险资料开展了一项回顾性研究，其中四分之三为白人，13％为黑人，8％为西班牙裔，其余来自其他种族。     

C-反应蛋白的种族和性别差异

目的:本试验旨在确定C-反应蛋白(CRP)水平分布有无种族和性别差异。背景:比较不同种族和性别人群的CRP水平分布的资料很少。最近在临床实践中推荐将CRP测定作为心血管疾病风险评估的因素,并提出了确定高相对风险的统一临界值(>3m g/L)。方法:检测了参与Dallas心脏研究(基于人群、多种族、概率采样的研究)年龄在30～65岁的2749例白人和黑人受试者的CRP,并比较了不同种族及性别组之间CRP水平的差异。结果:黑人受试者血清CRP水平高于白人受试者(中位值:3.0m g/L vs2.3m g/L;P<0.001),女性受试者CRP水平高于男性(中位值:3.3m g/L vs…     

首次接受治疗的不同种族HCV感染患者对相同剂量干扰素的应答率不同

背景:尽管丙型肝炎的治疗方法已经有了很大发展,但是人们尚未对不同种族和民族的患者群体对于各种治疗方法的不同反应进行深入研究。方法:330例从未接受过治疗的HCV感染患者,接受了干扰素诱导治疗,继之以1次/2d的干扰素治疗。超过30%的患者不是白人,因此可以比较不同种族或民族,不同基因型患者对治疗的反应。结果:24%白人患者,12%西班牙人患者和4%黑人患者产生了持续病毒学应答(SVR),这一比例在白人患者和非白人患者之间存在显著差异(P=0.003)。15%基因型1型的白人和13%基因型1型的西班牙人患者产生了SVR,2%基因型1型的黑人患者产生了S…     

充血性心力衰竭预后及治疗效果的种族差异

背景:种族是否影响充血性心力衰竭(CH F)的死亡率以及治疗效果目前尚不明确。方法:对来自DIG研究(评估地高辛对CH F患者发病率及死亡率的影响)的资料进行事后分析。结果:研究者对897例黑人患者及6660例白人患者进行了平均为期37个月的随访观察。与白人相比,黑人更为年轻(60±13     

高危非ST段抬高急性冠状动脉综合征黑人与白人患者治疗和预后的种族差异:源自CRUSADE(早期实施ACC/AHA指南和对不稳定型心绞痛患者进行快速风险分层能减少不良结局?)

背景:急性心肌梗死黑人患者接受冠状动脉介入治疗的可能性小于白人患者。尚不清楚非ST段抬高急性冠状动脉综合征(N STE-A CS)的其他治疗方法是否存在种族差异以及不同治疗方案如何影响预后。方法与结果:采用参与CRU SA DE(早期实施ACC/AH A指南和对不稳定型心绞痛患者进行快速风险分层能减少不良结局?)国家质量改进启动项目的400所美国医院的资料,确认高危NSTE-A CS犤心脏标记物阳性和(或)缺血性ST段改变犦的黑人和白人患者。经校正人口统计学资料和内科共病后,对比了不同种族中美国心脏病学会/美国心脏协会指南推荐用于N STE…     

黑人前列腺特异性抗原浓度高

目前公布的前列腺特异抗原(PSA)正常值范围是根据白人群体调查结果确定的,但黑人前列腺癌的发生率比白人高50％,且所有黑人在诊断前列腺癌时的PSA值均高于白人。因此需要明确黑人PSA的正常值范围是否高于白人。 Robert等收集了在美国巴尔的摩军事医学中心就诊的2888例黑人、3035例白人PSA检验     

Left ventricular hypertrophy in black and white hypertensives. Standard electrocardiographic criteria overestimate racial differences in prevalence.

OBJECTIVE--To assess racial differences in the accuracy of standard electrocardiographic (ECG) criteria in the diagnosis of left ventricular hypertrophy (LVH). DESIGN--The sensitivity and specificity of standard ECG criteria were compared in blacks and whites using echocardiographic LVH as the reference standard. SETTING--Eight worksite-based hypertension clinics in New York, NY. PATIENTS--A sample of 122 black and 148 white hypertensive patients. RESULTS--The prevalence of ECG-LVH was two to six times higher in blacks than in whites, depending on the criteria used (range, 6% to 24% in blacks vs 1% to 7% in whites; P = .0005 to .19 for black-white comparisons). The difference in prevalence of echocardiographic LVH [corrected], however, was less striking and did not attain statistical significance (26% in blacks and 20% in whites; P greater than .2). The sensitivity of the ECG was low (range, 3% to 17%) and did not differ significantly between the two races for any of the conventional criteria; specificity, however, was lower in blacks for all criteria (range, 73% to 94% vs 95% to 100% for whites; P = .0001 to .09). The predictive value of a positive ECG was consistently, although not significantly, lower in the black subjects. Black race was the strongest independent predictor of decreased ECG specificity in multiple logistic regression analysis that also considered age, gender, body mass index, left ventricular mass index, and smoking. CONCLUSIONS--Commonly used ECG criteria for the detection of LVH have a poor sensitivity in both black and white hypertensives and a lower specificity in blacks than in whites; this may lead to a greater number of false-positive diagnoses in black patients, as well as to an overestimation of black-white difference in LVH prevalence.     

The state of federal health statistics on racial and ethnic groups.

OBJECTIVE--To examine assumptions underlying federal health statistics on racial and ethnic groups in the United States. DATA SOURCES--Studies conducted by federal agencies and other investigators, and technical appendices of published vital statistics and census reports. DATA SYNTHESIS--Several assumptions underlying federal health statistics on racial and ethnic groups are not well supported. Conceptual (as opposed to operational) definitions of race and ethnicity are not available, and scientific grounds for definition are not considered. Procedures for the ascertainment of race and ethnicity vary within and among data-collection agencies. Miscounting and misclassification may vary by an order of magnitude between whites and other races. The responses of individuals to questions of racial and ethnic identity differ for different indicators, in different surveys, and at different times. As a result, counts, rates, and rate ratios may not be meaningful or accurate. Particularly for Hispanics and for races other than whites or blacks, there are inconsistencies in statistical information that may hinder health research and program development. CONCLUSIONS--Improvement of federal health statistics for racial and ethnic groups requires (1) clarification of goals for classification, (2) adoption of scientific principles for the validation and definition of the categories "race" and "ethnicity," (3) assessment of perceived social identity in the population, and (4) periodic evaluation.     

Inconsistencies in coding of race and ethnicity between birth and death in US infants. A new look at infant mortality, 1983 through 1985.

OBJECTIVE--To ascertain the consistency of the racial and ethnic classification of US infants between birth and death and its impact on infant mortality rates. SUBJECTS--All US infants born from 1983 through 1985 who died within a year. DESIGN--We used the national linked birth/infant-death computer tape, augmented with information on infants' race and ethnicity at death, to compare the coding of race and Hispanic ethnicity at birth and at death. We also assessed infant mortality rates by race and ethnicity as defined (1) by the standard algorithm and (2) by the rule that, beginning in published tabulations for 1989, assigns newborns the race of their mothers. Finally, we estimated infant mortality rates based on consistent coding of race and ethnicity at birth and death. RESULTS--Inconsistency in the coding of race is low for whites (1.2%), greater for blacks (4.3%), and greatest for races other than white or black (43.2%). Most infants reclassified at death (87.3%) are classified as white at death. Inconsistency in coding is lower for non-Hispanic whites (3.5%) and non-Hispanic blacks (3.3%) than for Hispanic populations (30.3%). Compared with the standard algorithm for calculation of infant mortality, consistent definition at birth and death produces rates 2.1% lower for whites, and higher for all other groups--3.2% for blacks, 46.9% for American Indians, 33.3% for Chinese, 48.8% for Japanese, 78.7% for Filipinos, and 8.9% for Hispanics. CONCLUSIONS--The coding of race and ethnicity of infants at birth and death is remarkably inconsistent, with substantial impact on the estimation of infant mortality rates. A need exists to reconsider the nature and definition of race and ethnicity in public health.     

SIDS: race as a factor

In Wisconsin, the rate of postneonatal deaths attributed to sudden infant death syndrome (SIDS) for the period 1978-1987 was 6.7 per 1,000 live births for Native Americans, 3.6 for blacks, and 1.4 for whites. To investigate racial differences in case ascertainment and risk for SIDS mortality, this study used matched birth-death certificate data for the 1,111 reported SIDS deaths during the 10-year period. At least 90% of all SIDS deaths occurred before 6 months of age; seasonal variation in time of death and autopsy rates were similar by race. The reported higher risk of SIDS for male infants and those with low birth weights did not occur among Native Americans. Low birth weight was a stronger risk for SIDS among whites than blacks. Our findings suggest that diagnostic practices may not account for racial differences in SIDS mortality. Patterns of risk, however, appear to vary by race.     

Black-white differences in stroke incidence in a national sample. The contribution of hypertension and diabetes mellitus

Although national data have consistently shown an increased risk of death from stroke among blacks, few studies have addressed the reasons for this excess mortality. We compared the incidence of stroke among 1298 blacks and 7814 whites, aged 35 to 74 years, in the 10-year follow-up of the respondents from the First National Health and Nutrition Survey. Blacks had a higher estimated incidence of stroke than whites even after adjustment for age, hypertension, and diabetes mellitus; the relative risk was 1.4 (95% confidence interval, 1.0 to 2.0) for black women and 1.1 (95% confidence interval, 0.8 to 1.6) for black men. The relative risks for stroke associated with hypertension and diabetes mellitus were unrelated to race. Although efforts to treat hypertension and diabetes are among the most important public health measures for reducing stroke, a more complete understanding of the determinants of stroke may be required to account for the excess stroke risk experienced by blacks.     

Cocaine use and HIV infection in intravenous drug users in San Francisco

We assessed risk factors for human immunodeficiency virus (HIV) infection in 633 heterosexual intravenous drug users. The HIV seroprevalence was 26% in blacks, 10% in Hispanics, and 6% in whites. Intravenous cocaine use significantly increased the risk of HIV infection, with a seroprevalence of 35% in daily cocaine users (odds ratio, 6.4; 95% confidence interval, 3.0 to 13.3). Black subjects were more likely to use cocaine regularly. Drug use in shooting galleries and sharing of drug injection equipment were also associated with HIV infection and were more common in cocaine users. By multivariate analysis, black race, daily cocaine injection by blacks and Hispanics, all other cocaine injection, heavy use prior to entry into methadone treatment by blacks, and use of drugs in shooting galleries were independent predictors of HIV infection. Methadone therapy was associated with substantial reductions in heroin use and some reduction in cocaine use, but 24% of cocaine users receiving methadone began or increased cocaine injection after entry into treatment.     

The excess incidence of diabetic end-stage renal disease among blacks. A population-based study of potential explanatory factors.

OBJECTIVE--To investigate whether the excess incidence of diabetic end-stage renal disease (ESRD) among African Americans could be explained by racial differences in putative ESRD risk factors. DESIGN--Population-based, ecologic study using the 1981 and 1982 Maryland Statewide Household Hypertension Survey for data on risk factor prevalence. PARTICIPANTS--A total of 2.1 million adults residing within the boundaries of the Maryland Regional ESRD Registry, grouped by race and ZIP code into 26 subpopulations. MAIN OUTCOME MEASURE--Incidence rates of treatment for diabetic ESRD between 1980 and 1985 from the Maryland Regional ESRD Registry by subpopulation. RESULTS--Between 1980 and 1985, 442 persons entered treatment for diabetic ESRD. At the level of the subpopulation, diabetic ESRD incidence was positively associated with black race (relative risk [RR], 3.42; 95% confidence interval [CI], 2.84 to 4.13), prevalence of diabetes (RR, 2.35; 95% CI, 1.92 to 2.87), prevalence of poorly controlled hypertension (RR, 1.80; 95% CI, 1.45 to 1.86), lack of a regular source of health care (RR, 1.82; 95% CI, 1.62 to 2.05), and lower socioeconomic status as indicated by lack of college education (RR, 1.41; 95% CI, 1.32 to 1.52) (all, P < .0001). After adjusting for these risk factors, black race remained strongly associated with the overall incidence of diabetic ESRD (RR, 2.70; 95% CI, 1.89 to 3.86; P < .0001). Further analyses suggested that this excess risk among blacks was confined to ESRD related to non-insulin-dependent diabetes (RR, 4.80; 95% CI, 3.09 to 7.46; P < .0001); blacks were at no higher risk than were whites for ESRD related to insulin-dependent diabetes (RR, 0.90; 95% CI, 0.52 to 1.55; P = .70). CONCLUSIONS--These data suggest that the excess incidence of diabetic ESRD among blacks is not fully explained by a higher prevalence of diabetes or hypertension in blacks or by racial differences in age, socioeconomic status, or access to health care. Instead, they suggest an increased susceptibility to ESRD resulting from non-insulin-dependent diabetes among blacks as compared with whites.     

Age, sex, ethnic origin and hospital admission for heart attack and stroke

The frequency of admission for heart attack and stroke in blacks, whites and Asians to Dudley Road Hospital, Birmingham, was studied. The study population (denominator) was 17 739 consecutive admissions to this hospital for the years 1975 to 1979, in 35- to 64-year-old men and women. Admission for heart attack was half as common in blacks compared with whites and, in some age groups, there was a slightly increased rate in Asians. By contrast, in both sexes and in all age groups, stroke admission was commoner in blacks. These differences cannot be explained by differing levels of blood pressure or cigarette smoking in the 3 ethnic groups.     

Racial differences in serum total bilirubin levels in health and in disease (pernicious anemia)

Common usage prescribes a single normal range for serum bilirubin levels. However, we have not only confirmed that men have higher levels than women but have discovered significant racial differences as well. Among 1,538 healthy Americans, blacks had lower mean bilirubin levels than whites of European origin, Latin Americans, and Asians. These racial differences, which were more pronounced among women than men, were maintained in pernicious anemia. Even though bilirubin levels rose in our 174 patients with this disease, they continued to be lower among blacks than among whites and Latin Americans. Moreover, the actual bilirubin level changes caused by pernicious anemia were themselves smaller among blacks. The racial differences, thus, persisted in pernicious anemia despite similar degrees of anemia, whereas the sex differences disappeared. We suggest that the lower serum bilirubin levels in blacks in health and disease do not stem primarily from lower bilirubin production than in whites.