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21.
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   
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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   
24.
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   
25.

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   
26.

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   
27.
Three sibs all presented in the early neonatal period with a salt-losing syndrome. The salt-losing form of congenital adrenal hyperplasia was diagnosed and appropriate treatment with glucocorticosteroids, mineralocorticosteroids, and additional dietary salt started. Although early life was maintained with difficulty, with age all 3 children required decreasing amounts of replacement steroids to maintain normal plasma electrolyte balance. They were reinvestigated at the ages of 15 years and 8 years (twins), when cortisol synthesis and metabolism proved normal, but aldosterone synthesis was blocked by deficiency of 18-dehydrogenase. Rational treatment of these cases of a salt-losing syndrome in which aldosterone synthesis alone is blocked due to lack of the enzyme 18-dehydrogenase requires the administration of a mineralocorticosteroid drug only. Since deoxycorticosterone (acetate or pivalate) requires intramuscular administration, as life-long therapy oral fludrocortisone is preferable. Although fludrocortisone has glucocorticoid activity, the "hydrocortisone equivalent" effect of the small dosage used was unlikely to inhibit either pituitary corticotrophin or growth hormone production.  相似文献   
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29.
输血是挽救创伤患者生命而普遍使用的治疗方法,但其又存在着明显和潜在的危险性。当今,经血液传播传染病和输血反应很少发生,但仍然存在。尽管在临床治疗中试图控制创伤患者休克的发展及损伤的严重度,但其输血后细菌感染、多脏器功能衰竭、死亡的发生率仍较高。  相似文献   
30.
The differentiation of the urinogenital system and the appendicular skeleton in vertebrates is under the control of Hox genes. The common control of digit and gonad differentiation raises the possibility that patterns of digit formation may relate to spermatogenesis and hormonal concentrations. This work was concerned with the ratio between the length of the 2nd and 4th digit (2D:4D) in humans. We showed that (i) 2D:4D in right and left hands has a sexually dimorphic pattern; in males mean 2D:4D = 0.98, i.e. the 4th digit tended to be longer than the 2nd and in females mean 2D:4D = 1.00, i.e. the 2nd and 4th digits tended to be of equal length. The dimorphism is present from at least age 2 years and 2D:4D is probably established in utero; (ii) high 2D:4D ratio in right hands was associated with germ cell failure in men (P = 0.04); (iii) sperm number was negatively related to 2D:4D in the right hand (P = 0.004); (iv) in men testosterone concentrations were negatively related to right hand 2D:4D and in women and men LH (right hand), oestrogen (right and left hands) and prolactin (right hand) concentrations were positively correlated with 2D:4D ratio and (v) 2D:4D ratio in right hands remained positively related to luteinizing hormone and oestrogen after controlling for sex, age, height and weight.   相似文献   
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