Biomedical subjects

W Li

Publications and source records attributed to W Li.

1,446 records · Page 81Linked to original sources

PubMedDate not supplied

MR angiography of the extracranial carotid arteries using a two-slab oblique 3-D acquisition.

PURPOSE: To describe an oblique, two-slab 3-D acquisition technique for MR angiography of the extracranial carotid arteries, an approach chosen to minimize saturation effects when the body coil is used as transmitter, as is often the situation when a dedicated neck coil is used as receiver. SUBJECTS: Five healthy subjects and 17 patients in whom carotid artery disease was suspected underwent MR angiography using the above technique. RESULTS: Flow contrast was much better than in direct sagittal acquisition. Comparisons between multislab transverse 3-D acquisition and the oblique approach showed that a greater length of the carotid arteries was depicted and scan time was less for oblique acquisitions. CONCLUSIONS: Use of oblique imaging is a simple and effective solution to the problem of coil-related saturation effects.

Adult↗

PubMedDate not supplied

Malignant lymphomas in Beijing.

We report on 1,082 cases of malignant lymphomas from the files of the Department of Pathology, Chinese PLA General Hospital, Beijing. We found non-Hodgkin's lymphomas (NHL) in 980 cases (91%) and Hodgkin's disease (HD) in the remaining 102 cases (9%). Among the NHL, the diffuse type was seen in 955 cases (97.4%) and the follicular type in 25 cases (2.6%). Among the diffuse NHL, the pleomorphic type was most frequently found (263 cases or 26.8%), followed in frequency by the mixed small and large cell (163 cases or 16.6%). The large-cell cleaved and noncleaved immunoblastic was found in 139 cases (14.2%), small cleaved cell in 132 cases (13.5%), lymphoblastic convoluted and nonconvoluted in 72 cases (7.3%), the small lymphocytic type in 128 cases (13.1%), plasmacytoid type in 40 cases (4.1%), and Burkitt type in 18 cases (1.8%). Using immunohistocytochemistry, we found T-cell lymphoma in 53% and B-cell lymphoma in 47% of cases. The distinctive differences of malignant lymphomas types between China and Western countries suggest the possibility of a relationship to environmental factors.

China↗

PubMedDate not supplied

Promoting heart health for Southeast Asians: a database for planning interventions.

This paper is a report of baseline data that the authors collected on the prevalence of hypertension in a sample of 397 Southeast Asian immigrants residing in central Ohio and the implications of those data for the design of ethnically approved and scientifically valid interventions. The context for collection of these data over a 9-month period in 1989 is described. Baseline demographic characteristics including distributions by ethnicity, sex, age, and length of stay in the United States, as well as family heart health history, hypertension level, and heart health awareness of these subjects are presented. For example, 85 percent of the immigrants did not know what could be done to prevent heart disease. Implications for the design of ethnically approved and scientifically valid prevention strategies are discussed. Based on these data, the authors realized that multiple health education strategies tailored to what they were learning about Southeast Asians would be needed. Through Southeast Asian leaders, they were led to using wall calendars, with words specific to each Southeast Asian language, that had a monthly heart health slogan as one avenue to reach Southeast Asians. Another strategy was to develop videotapes featuring cultural content but including heart health "commercials." The authors concluded that, although scientific validity of risk reduction interventions are important, customizing these strategies to ethnically specific modes of interaction are equally important.

Adolescent↗

PubMedDate not supplied

Intravenous ketorolac and subarachnoid opioid analgesia in the management of acute postoperative pain.

BACKGROUND AND OBJECTIVES: Ketorolac is a parenteral nonsteroidal anti-inflammatory drug that provides analgesia through a peripheral mechanism. The purpose of this study was to evaluate whether the scheduled administration of intravenous ketorolac improves the analgesia provided by subarachnoid opioids after surgery. METHODS: Patients undergoing major urologic surgery were enrolled in a randomized, placebo-controlled, double-blinded study and received one of two analgesic regimens. All patients were given subarachnoid opioid analgesia consisting of morphine (range, 0.55-0.8 mg) plus fentanyl (25 micrograms) at the completion of surgery just prior to awakening. In addition to subarachnoid opioids, patients received four doses of either intravenous placebo (group 1, n = 21) or ketorolac (group 2, n = 17) administered 30 minutes before the anticipated completion of surgery and at 6, 12, and 18 hours after surgery. Patients in group 2 who were 65 years old or older received 30 mg ketorolac initially, with subsequent doses of 15 mg. Those younger than 65 years of age received 60 mg ketorolac initially, with subsequent doses of 30 mg. Pain scores were assessed by a blinded observer using a 10-cm visual analog scale (VAS) at 1, 8, and 24 hours after the operation. Intravenous morphine requirements while in the postanesthesia care unit (PACU) and during the following 24 hours, as well as the incidence of pruritus, nausea, naloxone usage, and bleeding were also recorded. Results were analyzed using the Wilcoxon rank-sum, Fischer's exact, chi-square, and Student's t tests. RESULTS: Patients receiving intravenous ketorolac (group 2) in addition to subarachnoid opioids had significantly lower pain scores 1 hour after surgery, and required less supplementary intravenous morphine within the first 24 postoperative hours (P < .05). The percentage of patients requiring no analgesic intervention while in the PACU was significantly higher for those receiving ketorolac (P = .01). The incidence of opioid-related side effects was similar between groups, and no perioperative bleeding was observed. CONCLUSIONS: When used in conjunction with subarachnoid opioids, the scheduled administration of intravenous ketorolac during the first 24 hours after major urologic surgery significantly enhances analgesia and reduces the need for supplemental intravenous opioids without affecting the incidence of side effects. Intravenous ketorolac is a safe and useful adjuvant to subarachnoid opioids in the management of acute postoperative pain.

Acute Disease↗

PubMedDate not supplied

Multimodal basis for egocentric spatial localization and orientation.

The perceptual and sensorimotor mechanisms that guide our abilities at localizing and orienting in space integrate sensory information from vision and from a "body-referenced mechanism" that itself makes use of extraretinal signals regarding eye position relative to the head and head orientation relative to the body and to gravity. The experiments and theoretical treatment center on two perceptual dimensions: the visual perception of elevation and of orientation within the frontoparallel plane. Several experiments measuring localization in the horizontal plane are also treated. The experiments involve measurements of the physical elevation of visually perceived eye level (VPEL, a norm for perceived elevation), measurements of the physical orientation within the frontoparallel plane corresponding to visually perceived vertical (VPV), and measurements of the direction within a horizontal plane perceived as straight ahead (VPSA). VPEL and VPV are each significantly and systematically influenced by both the pitch and the roll of visual fields, and it is these influences that provide the basis for experimentally isolating the contributions of vision from those of the body-referenced mechanism. The VPEL discrimination is nearly invariant with variation in head and eye orientation. The possibility that influences from vision and from the body-referenced mechanism combine linearly is well supported. The visual influences on VPEL and VPV are controlled by the action of individual lines, and the same pitched-from-vertical lines (from pitched planes) or oblique lines within erect planes influence both discriminations. The Great Circle Model (GCM) accounts for the influences of individual lines, and contains rules for the influence of combinations of lines on both VPEL and VPV. GCM is interpreted by a 3-dimensional vector treatment in "egocentric orientation space."

Eye↗

PubMedDate not supplied

Combined influences of gravitoinertial force level and visual field pitch on visually perceived eye level.

Psychophysical measurements of the level at which observers set a small visual target so as to appear at eye level (VPEL) were made on 13 subjects in 1.0 g and 1.5 g environments in the Graybiel Laboratory rotating room while they viewed a pitched visual field or while in total darkness. The gravitoinertial force was parallel to the z-axis of the head and body during the measurements. The visual field consisted of two 58 degrees high, luminous, pitched-from-vertical, bilaterally symmetric, parallel lines, viewed in otherwise total darkness. The lines were horizontally separated by 53 degrees and presented at each of 7 angles of pitch ranging from 30 degrees with the top of the visual field turned away from the subject (top backward) to 30 degrees with the top turned toward the subject (top forward). At 1.5 g, VPEL changed linearly with the pitch of the 2-line stimulus and was depressed with top backward pitch and elevated with top forward pitch as had been reported previously at 1.0 g (1,2); however, the slopes of the VPEL-vs-pitch functions at 1.0 g and 1.5 g were indistinguishable. As reported previously also (3,4), the VPEL in darkness was considerably lower at 1.5 g than at 1.0 g; however, although the y-intercept of the VPEL-vs-pitch function in the presence of the 2-line visual field (visual field erect) was also lower at 1.5 g than at 1.0 g as it was in darkness, the G-related difference was significantly attenuated by the presence of the visual field. The quantitative characteristics of the results are consistent with a model in which VPEL is treated as a consequence of an algebraic weighted average or a vector sum of visual and nonvisual influences although the two combining rules lead to fits that are equally good.

Adult↗