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31.
A search for children presenting with signs or symptoms of cardiac rhabdomyomas was made through members of the paediatric section of the British Cardiac Society in order to establish their birth incidence, presenting features, clinical course, and the frequency of a concurrent diagnosis of tuberous sclerosis. Fifteen children were identified and 12 had tuberous sclerosis (80%). Heart failure was the presentation in six, five of whom died; six presented because of a murmur and three because of arrhythmias. The prevalence of echocardiographic evidence of cardiac rhabdomyomas in a population of patients with tuberous sclerosis was established. Twenty individuals had echocardiography and eight had echodensities consistent with cardiac rhabdomyomas. It is concluded that the minimum birth incidence for children presenting because of the effects of cardiac rhabdomyomas is 1/326,000 and a minimum of 80% have tuberous sclerosis. In a population of patients with tuberous sclerosis a minimum of 60% under 18 years have cardiac rhabdomyomas.  相似文献   
32.
To determine the outcome of congenital lung abnormalities, data were collected retrospectively between January 1991 and December 1996 on any foetus found to have a lung lesion on antenatal ultrasound. A total of 23 foetuses had lung lesions on antenatal ultrasound. In two foetuses the antenatal ultrasound showed bilateral enlarged "bright" echogenic lungs with evidence of hydrops. Both pregnancies were terminated and tracheal atresia was confirmed. In 15 foetuses the antenatal ultrasound appearance was of a unilateral "bright" echogenic lung. There was one case of bronchial atresia and two cases of congenital lobar emphysema, which all had surgery. In nine cases there was a reduction in the size of the lesion on serial antenatal ultrasounds and no lesion was detected after birth. In three cases a small lesion was present after birth on chest radiography. In six foetuses the antenatal ultrasound appearance was of unilateral cystic or mixed cystic and echogenic lung lesions. Two pregnancies were terminated; both had congenital cystic adenomatoid malformation. Four pregnancies were continued and three infants had surgery soon after birth and were confirmed to have had congenital cystic adenomatoid malformation. One infant has been managed conservatively. In conclusion, a definitive diagnosis cannot usually be made antenatally. A large lesion on initial scan does not necessarily predict a poor outcome. The natural history of small asymptomatic postnatal lesions is unknown and a long-term prospective study is needed to determine the outcome of these lesions.  相似文献   
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A prototype ultrafast cine computed tomographic (CT) scanner, designed specifically for cardiac imaging, was used to evaluate a preliminary series of patients with prior myocardial infarction (n = 21) and a control group without coronary artery disease (n = 5). Multilevel 50-msec CT scan exposures were obtained during peripheral intravenous bolus injections of contrast medium. A comparison was made between cine-CT scans and standard left ventriculographic images in assessing segmental left ventricular motion. Results indicate that cine CT, performed at sufficiently rapid speeds (20 scans per second) to allow useful analysis of regional ventricular wall motion, can provide adequate image quality. Analysis of 110 segments revealed a good correlation (90.9%) between the two techniques in characterizing normal from abnormal regional wall motion. Cine CT, based on this initial study, demonstrates considerable potential for evaluating not only cardiac chamber dimensions but also segmental wall dynamics.  相似文献   
35.
Human donor corneas were stored in McCarey-Kaufman (M-K) medium for 3 to 6 days; then they were mounted in the specular microscope, and the endothelial surface perfused with a glutathione-bicarbonate-Ringer solution. During storage, the corneal thickness increased 37% above an assumed normal of 0.520 mm. The corneas did not have sufficient active thinning to be accepted as viable when tested by the temperature-reversal phenomenon. Since comparable donor corneas have been used in successful penetrating keratoplasties, there must be a discrepancy between the cell viability as tested by the temperature-reversal phenomenon and clinical application.  相似文献   
36.
The results of Kr-81m/Tc-99m ventilation-perfusion (VP) lung scintigraphy were correlated with the results of pulmonary angiography for 74 patients suspected of having pulmonary embolism (PE). Among patients having a diagnostic scan, the sensitivity and specificity of scintigraphy were 91% and 94%, respectively. Also, 157 consecutive cases of Kr-81m/Tc-99m VP lung scintigraphy were reviewed, and the frequency of an indeterminate scan was found to be 22%. A similar frequency was found for VP scintigraphy with xenon-133. Of eight patients who had indeterminate scans due to the presence of a single VP mismatch, four were demonstrated to have PE by angiography. Kr-81m is an excellent agent for VP scanning in cases of suspected PE, offering accuracy in diagnosis as well as favorable physical properties.  相似文献   
37.
Background Patients with prostate cancer with a pre-operative prostate-specific antigen (PSA) τ;15ng/ml who undergo radical retropubic prostatectomy (RRP) generally do not have a good outcome, yet may have organ-confined cancer and should be offered the option of surgery. Aim To assess the outcome of patients who underwent RRP with a pre-operative PSA ≥ 15ng/ml. Methods Thirty-four patients, mean pre-operative PSA: 25.46ng/ml (15.03–76.6) and mean Gleason score: 6.4 (5–9) were assessed. Results Two groups were identified. Group I: 41% (14/34) have no biochemical recurrence to mean follow up of 58 months (30–106). Mean PSA: 18.8ng/ml (15.03–25.84). Mean Gleason score: 6.1 (5–7). Clinical stage: T1c in 80%. No patient had seminal vesicle or lymph node involvement. Group II: 59% (20/34) have biochemical recurrence or died (3) from their disease to mean follow up of 66 months (36–98). Mean PSA: 28.9ng/ml (15.28–76.6). Mean Gleason score: 6.7 (5–9). Clinical stage: T1c in 25%. Eleven patients had seminal vesicle (8) involvement or positive lymph nodes (3) or both (2). Conclusion RRP seems feasible in patients whose pre-operative PSA is between 15 and 25ng/ml with stage T1c, Gleason score ≤ 7 and negative lymph node frozen section.  相似文献   
38.
OBJECTIVE: To assess whether iris color and eyelash changes occur with the use of unoprostone for 2 years. DESIGN: The 2 clinical trials described herein were prospective, randomized, double-masked, active-controlled, parallel group, multicenter studies. PARTICIPANTS: A total of 1131 patients with primary open-angle glaucoma or ocular hypertension participated in 2 clinical trials and received either unoprostone isopropyl 0.15% (659), timolol maleate 0.5% (331), or betaxolol hydrochloride 0.5% (141), 1 drop per eye twice daily for up to 24 months. METHODS: Color photographs (1:1 magnification) were taken of the iris and eyelid of each patient at baseline and at regular intervals thereafter through month 24 using a standardized camera system. Photography included 7 views of each eye plus a calibration photograph and a patient identification photograph, for a total of 16 photographs per patient per visit. Two independent (masked) readers subjectively compared baseline iris colors to subsequent visits. Side view photographs of the upper and lower eyelashes were used for the eyelash length analysis, with each having sufficient depth of field and a sufficient number of eyelashes in focus. Similarly, frontal eyelash views were used for the eyelash density analysis. MAIN OUTCOME MEASURES: Changes from baseline in iris color and eyelash length and density within and between treatment groups. RESULTS: Seven cases of iris color change (1.06%) were confirmed in patients treated with unoprostone for up to 24 months; no confirmed cases were reported in the timolol or betaxolol groups. In the unoprostone group, cases of iris color change were confirmed at months 12 (1 case), 18 (2 cases), and 24 (4 cases). No clinically relevant differences were observed among treatment groups for changes from baseline in eyelash length or density. CONCLUSION: Although iris hyperpigmentation and abnormal eyelash changes may occur after treatment with unoprostone, the incidence of these events appears to be low in the 2-year clinical study.  相似文献   
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Kapila  A; Chakeres  DW 《Radiology》1986,160(1):265-267
A new technique has been designed to improve myelography examinations of the entire lumbar spinal canal in patients with severe spinal stenosis using a single needle puncture. When a high-grade obstruction to the caudal flow of contrast material is encountered, the patient is placed in a flexed sitting position for 1 minute. This technique was performed in eight patients with severe lumbar spinal stenosis. It successfully helped depict the lower lumbosacral canal below an apparently complete block in four patients and resulted in improved visualization of the lower sac in four patients with partial block.  相似文献   
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