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141.
In 1987 and 1994 all UK regional neonatal intensive care units were questioned about their feeding policies for the ventilated preterm infant. Between 1987 and 1994 there was an increase in the use of milk feeds (59 versus 71%), fortified breast milk (5 versus 72%) and low birthweight formula (41 versus 69%) whilst use of donor breast milk declined (56 versus 22%). Units that gave enteral feeds used significantly less parenteral nutrition ( p < 0.05). Overall there was a tendency towards greater uniformity in feeding policies. 相似文献
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143.
Purpose: The localization of dopamine D| receptors (DIR) in the chicken retina was examined using an anti-human DI R. monoclonal antibody and PAP techniques. Results: A clear band of staining was seen in the outer plex-iform layer; as well as cellular staining in the outer-most part of the inner nuclear layer probably in a subset of horizontal cells. Many different amacrine cell bodies were labelled in the inner one-third of the inner nuclear layer. There was also extensive staining in the inner plexiform layer; which showed some striation. Occasional labelled ganglion cells were also detected. Conclusion: Localization of DI-dopamine receptors has 相似文献
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146.
A prototype 5,000-word recognizer for the generation of radiologic reports by voice entry was evaluated. The system had a capacity sufficient enough to include all radiologic examinations and all desired words in one lexicon. The lack of such a capacity had been identified as a major limitation of a 1,000-word system previously evaluated. Overall reliability in word recognition was 98%. The device may be widely applicable for use in any radiology practice. 相似文献
147.
Paraspinal lipomatosis: a benign mass 总被引:1,自引:0,他引:1
Paraspinal lipomatosis usually occurs in patients with steroid excess. In two patients a paraspinal mass was detected on conventional radiographs and was subsequently shown to represent benign fat deposition on computed tomography, thereby obviating further studies. Neither patient had been receiving steroids. Paraspinal lipomatosis may be the cause of a benign mass and may be considered in the differential diagnosis of this finding. 相似文献
148.
Diagnosis of internal jugular vein thrombosis 总被引:2,自引:0,他引:2
Six patients, aged 14-83 years, were shown by computed tomography (CT) to have thromboses of the internal jugular vein. In all cases, medical attention was sought only after a delay (4-21 days). In no case was the provisional clinical diagnosis correct, with working diagnoses ranging from abscess to neoplasm. A wide variety of likely causes was discovered, including venous catheters, local malignancy, infective cervical adenopathy, and polycythemia. CT showed distended veins with enhancing walls, low-attenuation intraluminal filling defects, and swelling of the adjacent soft tissues. Four of the six patients also underwent ultrasound examinations, which showed the veins to be distended and nonpulsatile, with internal echoes. Both modalities proved reliable and accurate. Because of the subtle and often non-specific clinical findings, it is likely that more clinically unsuspected cases will be encountered by the radiologist. 相似文献
149.
Coleman BG; Arger PH; Grumbach K; Menard MK; Mintz MC; Allen KS; Arenson RL; Lamon KA 《Radiology》1988,168(3):639-643
Transvaginal (TV) and transabdominal (TA) sonography were compared in a prospective study. A total of 230 examinations (126 pelvic, 104 pregnancy) were performed on 215 patients, ranging in age from 14 to 80 years. The improved anatomic detail on TV scans yielded new information in 138 (60%) examinations and better visualization of pelvic structures in 51 (22%) examinations. There was no important difference in diagnostic information provided by the two imaging modalities in 36 (16%) cases, and TV images were worse in five (2%). The clinical diagnosis was altered on the basis of TV sonographic findings in 54 (24%) cases and confirmed with certainty in 166 (72%). Diagnostic problems posed by TA scanning were not resolved by TV scanning in ten (4%) instances. Statistical analysis indicated that TV scanning was significantly better than TA scanning in the visualization of gestational sac contents (P less than .005), detection of fetal heart motion (P less than .001), and evaluation of the endometrial canal in the retroverted or retroflexed uterus (P less than .001). TV scanning was significantly better than TA scanning in visualization of the ovaries in patients with uterine leiomyomas (P less than .005) but not significantly better in peri- and postmenopausal patients (P greater than .05). 相似文献
150.
There appears to be a fundamental step-transition in retinal function at low light intensities, close to the scotopic-mesopic transition. This step-transition is observed for elements of the retinal dark-light switch, which has been described in the chicken retina. Over the same range of light intensities, there is a step-transition in photoreceptor retinomotor movements and in the coupling of horizontal and All amacrine cells, which suggests a switch in retinal circuitry from rod-processing to cone-processing regimes. A similar step-transition in pineal function suggests that the retinal step-transition signals to the central circadian systems. Finally, this step-transition may also inhibit eye growth, and thus be responsible for the reported diurnal rhythm in eye growth. Disturbances to this step-transition may be the initial cause of disordered eye growth in the form-deprivation myopia paradigm. 相似文献