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Objective: To describe a new technique for assessing fetal growth using three-dimensional ultrasonography (3DUS) using the extended imaging virtual organ computer-aided analysis (XI VOCAL) software and its respective reference curves.

Methods: We conducted a cross-sectional study on 303 normal singleton pregnancies between their 20th and 34th weeks. To assess fetal heart growth, we used the XI VOCAL software with 10 planes in which the reference lines (beginning and end) were placed at the cardiac apex, the output level of the vessels and the base above the diaphragm, respectively. To assess the correlation between distance and interval, polynomial regressions were performed with adjustments using the coefficient of determination (R2). To assess the inter-observer reproducibility, we used the intraclass correlation coefficient (ICC).

Results: The mean distance between the apex and the base of the fetal heart ranged from 14.41?±?1.24?mm to 26.24?±?2.62?mm between the 20th and 34th weeks, respectively. The mean interval between the apex and the base of the fetal heart ranged from 1.56?±?0.13?mm and 2.94?±?0.30?mm between the 20th and 34th weeks, respectively. We observed good correlation of distance and interval with the gestational age, with R2?=?0.73 and 0.74, respectively. We observed a good inter-observer to the interval and distance with ICC?=?0.983 and 0.996, respectively.

Conclusion: We described a new technique for assessing fetal heart growth using 3DUS and determined reference curves for the distance and interval between the 20th and 34th weeks of pregnancy.  相似文献   
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OBJECTIVE: There is considerable evidence that the amplitude of the heritable P300 event-related potential (ERP) is reduced in alcoholics and their alcohol-naive children. Low voltage alpha (LVA), a heritable resting electroencephalogram (EEG) trait present in 7-14% of the population, has been shown to be associated with alcoholism and anxiety disorders. A few studies have demonstrated a modest correlation between pre-stimulus alpha power and P300 amplitude. We aimed to test this finding in community volunteers, hypothesizing that LVA would be associated with low P300 amplitude. METHOD: Digitized resting EEG was recorded at the central parietal site (Pz) from 85 male and 113 female community volunteers (120 unrelated). ERPs were elicited at Pz by auditory and visual oddball paradigms. All participants were interviewed with the Schedule for Affective Disorders, Lifetime Version (SADS-L) and assigned blind-rated psychiatric diagnoses according to the American Psychiatric Association DSM-III-R criteria. RESULTS: LVA participants (including alcoholics and nonalcoholics) had significantly lower auditory and visual P300 amplitudes. Absolute alpha power was modestly correlated with auditory and visual P300 amplitude and was associated with 9.4% and 4.6% of the variance, respectively. CONCLUSIONS: The association between LVA and low P300 amplitude, two distinct electrophysiological traits, suggests that, at least in individuals with the LVA trait, some aspects of resting, unstimulated brain activity and activated brain function in the form of attentional response may be fundamentally related.  相似文献   
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An interferometric acuity device (Takata) has been used to study visual resolution in individuals with possible demyelinating disease. The instrument employed provides a large field with a continuous range of grid or fringe frequencies and a relatively intense (105 mean photopic trolands) stimulus. After a brief period of time with eyes closed, resolution thresholds of patients are repeatedly determined during a five minute period. In all individuals suspected of having a demyelinating disease tested to date, a fall off in resolution capability has been found in time when using this intense stimulus display. This occurs whether eye signs have been present, are present or have not yet been observed. Normal observers do not exhibit comparable decrements. The fall off in resolution capability may or may not occur at lower stimulus levels, and is often not revealed when testing routine Snellen acuity. Outer and inner retinal pathology (division based on vascular support) do not cause a comparable fall off in resolution in time. The interferometric acuity test is a non-invasive, easily applied test.This research has been supported in part by National Eye Institute Research Grant No. EY 01418, and Training Grant No. EY 07046 (to JME), National Institutes of Health, Bethesda, Maryland, and in part by a Fellowship supported by Fight for Sight, Inc., New York, in tribute to the memory of Hermann Burian, M. D. (to ECC).Presented at the International Ophthalmological Optics Symposium, May 8–9, 1978, Tokyo, Japan. Reproduced with the permission of the Chairman.  相似文献   
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BACKGROUND: Controlled reperfusion with terminal warm blood cardioplegia (TWBC) improves myocardial performance after global ischemia. However, the optimum volume required is unknown. METHODS: Fifty patients undergoing elective coronary artery bypass graft surgery were prospectively randomized to receive either 250 or 500 mL of TWBC. During TWBC delivery, and for 10 minutes after cross-clamp removal, samples were taken from the aorta and coronary sinus to measure the hydrogen ion, lactate, and oxygen content. RESULTS: At the end of TWBC delivery, the 500 mL group had significantly less hydrogen ion washout (p = 0.006) compared with the 250 mL group. Also, more hydrogen ions (p = 0.02) and lactate (p = 0.02) had been washed out during the entire period of TWBC delivery in the 500 mL group compared with the 250 mL, indicating better metabolic recovery. By 4 minutes after aortic cross-clamp removal, hydrogen ion and lactate washout, as well as oxygen extraction was similar in the two groups. However, the time to return to regular mechanical activity was prolonged in the 500 mL group, 5.8 (3) versus 4.6 (3) minutes in the 250 mL group (p = 0.05). Though there was no difference in postoperative Troponin T levels, eight patients in the 500 mL group versus four in the 250 mL group required ionotropic support (p = 0.1). CONCLUSIONS: A total of 500 mL of hotshot achieves a better metabolic state after hotshot delivery. However, there is no clinical benefit or improvement in the postoperative Troponin T release suggesting that in a short ischemic time, 500 mL TWCB has a limited clinical benefit.  相似文献   
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