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71.
The relationship between quality of life (QOL) assessments and decision making, in relation to the delivery of health services, is subjected to critical appraisal. Three levels of decision making in the health care system are taken into account in the analysis. Criticisms of opinion polling provide the basis for the appraisal. Examples of criticisms considered are: Might the use of QOL information be manipulative? Could the interviews or questionnaires used to obtain QOL data influence personal opinions? Are the methods used sometimes defective and/or superficial? Will QOL information always be used in decision making in ways that are ascertainable and justifiable? It is concluded that the time has come for the main focus of critical appraisal in QOL research to shift, from an emphasis on evaluation of the quality of methods used for assessments of QOL, toward an emphasis on the practical usefulness of QOL data. 相似文献
72.
The screening histories of all 348 women with invasive cervical cancer diagnosed in 1992 in 24 self-selected district health authorities and health boards in England, Wales and Scotland were compared with those of 677 age- and residency-matched controls. The controls were randomly selected from the family health services authority (FHSA) register. Screening histories, comprising the dates and results of all smears taken before the date of diagnosis of the patient''s cancer, were determined from the FHSA computer and laboratory records. We estimate that the number of cases of cervical cancer in participating districts in 1992 would have been 57% (95% confidence interval 28-86%) greater if there had been no previous screening. In women under the age of 70 it would have been approximately 75% (31-115%) greater. Extrapolation of the results from this pilot suggests that screening prevented between 1100 and 3900 cases of invasive cervical cancer in the UK in 1992. Women with stage 1B cancer or worse were more likely to have no record of previous screening than controls: 47% of these women under the age of 70 had been adequately screened according to current (5 yearly screening) guidelines, compared with 75% of matched controls. Thirteen per cent of all patients under age 70 had screening histories indicative of inadequate follow-up of smears requiring colposcopy. The proportion of microinvasive cases with screening predating diagnosis was similar to the proportion of controls. There was a strong correlation between stage and age: 56% of cancers in women under 35 were microinvasive compared with just 9% in women 65 years or over. The ''relative protection'' following a negative smear was greatest in the first 12 months and fell off towards the end of the fifth year. These data suggest that full adherence to current guidelines could perhaps have prevented another 1250 cases, but additional steps would have been required to prevent some of the 2300 remaining cases in women under the age of 70. 相似文献
73.
《Orthodontic Waves》2007,66(2):41-51
Though not frequent, the first or second molars are sometimes selected as candidates for the teeth extracted for orthodontic treatment. Most of molar extraction cases published in the journals show the typical Class II molar relation with extraction of maxillary second molars and mandibular third molars, or the Class I crowding case with extraction of four second molars. Meanwhile, a variety of molar extraction cases presents in Japanese patients.This study including 60 Japanese patients was conducted to reveal the facts on the treatment with first or second molar extraction and identify the pros and cons of the therapy. Clinical indications for molar extraction are proposed, which are classified into nine categories and each case in every category is shown. Some considerations during treatment and keys to successful results are also presented. 相似文献
74.
75.
背景 乳腺癌位居全球女性癌因死亡首位,具有发病率高、疾病负担重等特点。目的 评估1990—2019年中国女性乳腺癌发病率及死亡率的流行变化趋势。方法 提取《2019年全球疾病负担》数据库中1990—2019年中国≥15岁女性乳腺癌发病及死亡数据,应用年龄-时期-队列的贝叶斯模型对中国1990—2019年女性乳腺癌发病及死亡趋势进行拟合,进一步估计中国女性乳腺癌发病及死亡风险中的年龄效应、时期效应和队列效应。结果 1990—2019年中国女性乳腺癌粗发病率从14.14/10万升至52.81/10万,粗死亡率从7.22/10万升至13.40/10万。乳腺癌标化发病率总体呈上升趋势(1990年为17.07/10万,2019年为35.61/10万),标化死亡率呈平稳略减趋势(1990年为9.16/10万,2019年为8.98/10万)。年龄-时期-队列模型分析结果显示:所有年龄组女性乳腺癌发病率净漂移值为2.58%〔95%CI(2.34%,2.83%)〕,局部漂移值在65~69岁年龄段达到最高,为3.46%〔95%CI(3.11%,3.80%)〕;死亡率净漂移值为-0.75%〔95%CI(-1... 相似文献
76.
OBJECTIVE: To examine the prevalence and correlates of self-reported urogenital symptoms (dryness, irritation or itching, discharge, dysuria) among postmenopausal women aged 50-79. DESIGN: A cross-sectional analysis based on n=98,705 women enrolled in the US-based Women's Health Initiative observational study and clinical trials. Urogenital symptoms, symptom severity (mild, moderate, severe), and all covariates were self-reported through questionnaires at enrollment. Prevalence rates of each urogenital symptom were examined and logistic regression was used to identify potential correlates. RESULTS: Prevalence rates for each symptom were: dryness, 27.0%; irritation or itching, 18.6%; discharge, 11.1%; and dysuria, 5.2%. Four factors were correlated with two or more symptoms: Hispanic ethnicity (adjusted odds ratio (AOR)=2.1-3.1 versus white women across all symptoms), obesity (AOR=2.2 severe discharge versus none, AOR=3.6 severe irritation/itching versus none), treated diabetes (pills or shots) compared to no diabetes (AOR=2.4 severe dysuria versus none, AOR=3.2 severe irritation/itching versus none), and vaginal cream HRT/ERT compared to those who never used HRT/ERT (AOR=4.4 severe dryness versus none, AOR=4.6 severe irritation/itching versus none). Factors not associated with the symptoms included sexual activity, age, years since menopause, current smoking, marital status, gravidity, and natural versus surgical menopause. CONCLUSIONS: This is the first report to document urogenital symptoms by race/ethnicity among an exclusively postmenopausal population. We found an elevated prevalence of urogenital symptoms among women who are Hispanic, obese, and/or diabetic. Confirmation of our findings in these subgroups, and, if confirmed, analysis on why these populations are at greater risk, are areas for future research. 相似文献
77.
目的探讨皖籍汉族人群MICA基因(major histocompatibility complex class Ⅰchain-related gene A,MICA)第2、3、4外显子的多态性,及其与HLA-B抗原的连锁不平衡在强直性脊柱炎(ankylosing spondylitis,AS)发病中的作用。方法采用聚合酶链反应-序列特异性寡核苷酸探针杂交(polymerase chain reactionsequence-specific oligonucleotide probing,PCR-SS0)技术对56例AS患者和112名正常对照人群进行MICA基因第2、3、4外显子的多态性和HLA-B抗原的检测。结果AS患者和正常对照人群的MICA等位基因分布均以MICA*008占优势,频率分别为32.14%和30.36%。两组人群MICA*007等位基因的分布差异有统计学意义(X^2=10.18,P〈0.05,RR=2.50)。单倍型分析显示,AS患者和正常对照人群的MICA等位基因均显示出与多个HLA-B位点的连锁不平衡现象,两组间差异有统计学意义的单倍型为MICA*007-B27(X^2=18.46,P〈0.05,RR=7.47)。分层分析结果显示,HLA-B27阳性与AS的相关性有统计学意义(P〈0.05),但MICA*007基因与AS的相关性无统计学意义(P〉0.05)。结论AS患者中MICA*007等位基因频率的显著升高可能源于MICA基因与HLA-B位点间的广泛连锁不平衡。 相似文献
78.
Parle-McDermott A Mills JL Kirke PN O'Leary VB Swanson DA Pangilinan F Conley M Molloy AM Cox C Scott JM Brody LC 《Journal of human genetics》2003,48(4):190-193
The thermolabile variant (677TT) of methylenetetrahydrofolate reductase (MTHFR) is a known risk factor for neural tube defects
(NTDs). The relationship between a second MTHFR polymorphism (1298A→C) and NTD risk has been inconsistent between studies.
We genotyped 276 complete NTD triads (mother, father and child affected with an NTD) and 256 controls for MTHFR 1298A→C. Our
findings do not support a role for the 1298A→C polymorphism in NTDs (OR 0.85 (95% CI 0.49–1.47), p= 0.55), nor do we observe a combined effect with the 677C→T polymorphism.
Electronic Publication 相似文献
79.
Martijn W Heymans Dirk L Knol Willem van Mechelen Henrica CW de Vet 《BMC medical research methodology》2007,7(1):33
Background
Missing data is a challenging problem in many prognostic studies. Multiple imputation (MI) accounts for imputation uncertainty that allows for adequate statistical testing. We developed and tested a methodology combining MI with bootstrapping techniques for studying prognostic variable selection. 相似文献80.
Is fecundability associated with month of birth? An analysis of 19th and early 20th century family reconstitution data from The Netherlands 总被引:1,自引:4,他引:1
Smits LJ; Van Poppel FW; Verduin JA; Jongbloet PH; Straatman H; Zielhuis GA 《Human reproduction (Oxford, England)》1997,12(11):2572-2578
The relationship between fecundability and month of birth was investigated
in a cohort of 1526 women who married between 1802 and 1929, using only
women whose first marriage occurred before the age of 35 years. On the
basis of their time to pregnancy (TTP, calculated as time between wedding
and first birth minus gestational length), women were categorized into two
groups: fecunds (TTP up to 12 months or prenuptial conceptions, n = 1348)
and subfecunds (TTP >18 months, n = 118). By use of logistic regression,
cosinor functions with a period of 1 year or 6 months and variable shift
and amplitude were fitted through the monthly odds of subfecunds versus
fecunds. The best fitting curve was unimodal, with a zenith in September (P
= 0.13 for H0: no differences). Exclusion of childless women (n = 36,
minimum follow-up 5 years) from the subfecunds led to a similar curve (P
< 0.01), while childless women, as compared with fecunds, showed a birth
distribution that was best represented with a bimodal curve with zeniths in
January and July (P = 0.06). This study provides evidence for the existence
of differences in fecundability by month of birth. The cause of this
relationship is unclear, but may lie in a melatonin-dependent circannual
variability of the quality of the oocyte.
相似文献