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51.
Eleven women with a history of infertility and uterine leiomyomas underwent magnetic resonance (MR) imaging of the pelvis prior to myomectomy. Nine also underwent preoperative pelvic ultrasonography (US), and ten underwent hysterosalpingography. All studies were interpreted prospectively by independent observers. With each imaging modality, the location (one of 11 anatomic segments), size, and appearance of detected uterine leiomyomas were determined and compared with surgical and histologic findings. Among the nine patients who underwent both MR and US, the sensitivity (85%) and accuracy (94%) of MR imaging for abnormal segments was significantly better than that of US (sensitivity = 69%, P = .015; accuracy = 87%, P = .043). For the ten patients who underwent both MR and hysterosalpingography, the sensitivity (91%) and accuracy (96%) of MR imaging was better than that of hysterosalpingography (sensitivity = 18%, P = .0005; accuracy = 72%, P = .0005). The specificities of the three modalities did not significantly differ (100%, 97%, and 98% for MR, US, and hysterosalpingography, respectively). These data suggest that MR imaging is superior to US or hysterosalpingography for preoperatively locating uterine leiomyomas.  相似文献   
52.
53.
Concepts necessary to an understanding of the basics of quality assurance audits are presented. Included are specific examples that bridged theory and practice by applying the protocol to a real-life diagnostic imaging situation. This method meets the present requirements of the Joint Commission of the Accrediation of Hospitals.  相似文献   
54.
Patient dosage in computed tomography   总被引:1,自引:0,他引:1  
McCullough  EC; Payne  JT 《Radiology》1978,129(2):457
  相似文献   
55.

Background

The purpose of this study was to determine the test-retest reliability of temporal and spatial gait measurements over a one-week period as measured using an instrumented walkway system (GAITRite®).

Methods

Subjects were tested on two occasions one week apart. Measurements were made at preferred and fast walking speeds using the GAITRite® system. Measurements tested included walking speed, step length, stride length, base of support, step time, stride time, swing time, stance time, single and double support times, and toe in-toe out angle.

Results

Twenty-one healthy subjects participated in this study. The group consisted of 12 men and 9 women, with an average age of 34 years (range: 19 – 59 years). At preferred walking speed, all gait measurements had ICC's of 0.92 and higher, except base of support which had an ICC of 0.80. At fast walking speed all gait measurements had ICC's above 0.89 except base of support (ICC = 0.79),

Conclusions

Spatial-temporal gait measurements demonstrate good to excellent test-retest reliability over a one-week time span.
  相似文献   
56.
The normal timing for first-trimester nuchal translucency screening of aneuploidies is 10 to 14 weeks' gestation. We describe a fetus with trisomy 18 that presented at 11 weeks with increased nuchal thickness. Reevaluation at 12 and 13 weeks showed early return to normal of the increased nuchal measurement.  相似文献   
57.
AIMS AND BACKGROUND: The objectives of the present study were to validate the social stratification variables adopted by the European Prospective Investigation into Cancer and Nutrition (EPIC) by comparing them with data from another independent source and to evaluate the geographic and social distribution of eating habits in the Italian EPIC population. METHODS: The validation of the socioeconomic data collected by the EPIC study was performed with the Turin Longitudinal Study as gold standard and using Cohen's kappa statistics to evaluate the concordance between the studies. We then analyzed food groups based on the consumption of meat and fats, carbohydrates, sweets and alcohol, and on an index of the Mediterranean diet. The standardized scores for each food group were subdivided into quartiles, which were used to compare persons in the extreme quartiles. Analysis of the differences in eating habits by center and by educational level was conducted separately for men and women, calculating the prevalence rate ratios and controlling for age, area of birth and body mass index. RESULTS: Concordance between the two data sources was high for educational level and low for the social-class index based on occupation. Most of the eating habits considered to be potentially harmful (high consumption of meat or fats and alcohol and low consumption of olive oil and fish) were more frequent in Northern than in Southern Italy. These habits were inversely correlated with educational level, especially in the South. CONCLUSIONS: A significant improvement in health could be obtained in the Italian population if culturally and socioeconomically disadvantaged individuals were to abandon their diet rich in meat and fats, as done by more advantaged persons. In the absence of preventive interventions specifically addressed to disadvantaged groups, it is likely that social inequalities in mortality and morbidity will increase.  相似文献   
58.

OBJECTIVES:

To determine patterns of follow-up and prenatal education by family physicians and to assess whether practice patterns comply with the 1996 Canadian Paediatric Society/Society of Obstetricians and Gynecologists of Canada (CPS/SOGC) guidelines for early neonatal discharge.

DESIGN:

Mail survey.

SETTING:

A community of 300,000 people who were served exclusively for obstetrical care by a tertiary care hospital that performs 5000 deliveries per year and provides an early discharge program (EDP).

PARTICIPANTS:

Family physicians who provide prenatal and/or newborn care.

MAIN OUTCOME MEASURES:

The timing of neonatal follow-up and parental teaching by family physicians.

RESULTS:

Thirty-two per cent of the respondents scheduled their first postnatal visits two or more weeks after early discharge. There was no significant difference (P=0.7) in scheduling of follow-up for babies who were part of an EDP compared with those who were not. Fewer than 20% of physician respondents provided antenatal education in preparation for early discharge.

CONCLUSIONS:

The 1996 CPS/SOGC guidelines for physician follow-up after early neonatal discharge and for anticipatory parental education are not being followed consistently; however, these guidelines were disseminated without reinforcement. Until further study supports a change in practice guidelines, appropriate implementation strategies must be employed to ensure compliance.  相似文献   
59.
BACKGROUND: Anorexia nervosa is associated with lower left ventricular mass (LVM) and systolic dysfunction. Whether these abnormalities reflect chronic protein-energy malnutrition or are primarily related to lower cardiac workload is unclear. OBJECTIVE: The objective of the study was to verify whether low LVM in anorexia nervosa is explained by low hemodynamic load. DESIGN: Ninety-one women with anorexia nervosa [macro x +/- SD age: 20.5 +/- 6.1 y; body mass index (in kg/m(2)): 15.6 +/- 1.9; group 1] and 62 normal-weight female control subjects (age: 22.5 +/- 5.5 y; body mass index: 20.9 +/- 1.2; group 2) underwent Doppler echocardiography. LVM was evaluated as the percentage predicted by body height, sex, and stroke work (systolic blood pressure x stroke volume). RESULTS: The left ventricular chamber dimension was smaller and the chamber walls were thinner in group 1 than in group 2, which resulted in significantly lower LVM and LVM indexes (P < 0.0001). Ejection fraction, heart rate, stroke volume, and cardiac output were significantly (P < 0.007) lower in group 1, but peripheral resistance was substantially higher (P < 0.0001). The deviation of LVM from predicted values was lower and the proportion of subjects with inadequate LVM was significantly higher in group 1 than in group 2 (P < 0.0001). This difference was attenuated after adjustment for body weight and heart rate. There were no relations between LVM and laboratory tests in group 1. CONCLUSIONS: Anorexia nervosa is a condition of low hemodynamic load that leads to low LVM. Even with adjustment for stroke work, however, LVM is lower than would be predicted by height, because of the effect of body weight reduction (ie, wasting of lean body mass).  相似文献   
60.
The objective of this study was to characterize longitudinal patterns of drug injection behavior for individuals and to identify their early determinants. Participants were 1,339 injection drug users recruited into the AIDS Link to Intravenous Experience (ALIVE) Study in Baltimore, Maryland, through community outreach efforts. The study was initiated in 1988, and follow-up continued through 2000, with semiannual visits. Patterns of self-reported drug injection (yes/no) were defined for each participant, based on the number of drug-use transitions. The effect of baseline factors was assessed using multinomial logistic regression models. Over the 12-year study period, four patterns were noted: 29% of participants remained persistent drug injectors, 20% ceased injection, 14% relapsed once, and 37% had multiple transitions. Persistent injectors had the shortest follow-up and the highest mortality. For persons who changed their behavior, 3.4 years elapsed before their first cessation attempt, on average. Factors differentiating the groups included history of incarceration, young age, participation in drug treatment programs, recent overdose, and commercial sex. The observed long-term injection patterns are consistent with the view of drug addiction as a chronic disease. This view emphasizes the need for prolonged efforts to sustain cessation and to prevent adverse health and social outcomes among injection drug users.  相似文献   
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