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101.
Millions of people work or spend their free time sitting in front of VDUs that induce contingent visual effects. However, only a few notice irritations in the course of everyday work: motion after-images such as the waterfall illusion or tilt after-effects are possible. A new effect may be caused by those new VDU monitors which have an almost square pattern in the display matrix in which the vertical lines are thicker than the horizontal lines. After-images persisting for days are described when this pattern has an edge length of 0.3 mm and over. These effects are of little concern to most users of VDUs.  相似文献   
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Anesthesia inhibits arterial baroreflex functions such as baroreflex sensitivity (BRS). The main objective of the present study was to determine the time course of BRS recovery from anesthesia and to determine whether BRS recovery is synchronous with the recovery of consciousness and blood pressure (BP). Experiments were performed in male Sprague-Dawley rats using different commonly used anesthetics at routine doses through intraperitoneal administration: (1) diazepam/ketamine,  相似文献   
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We examined the incidence, aetiological factors and outcome in 40 cases of nonimmune hydrops fetalis (NIH) and suggest a rational approach to management. The incidence of NIH was 1 in 830 deliveries during the last 10-year period. In spite of extensive antenatal and postnatal investigation no cause could be established in 14 (35%) cases. A probable aetiological factor was found in 65% of cases. These included viral infection (7), cardiovascular (6), twin-to-twin transfusion (3), chromosomal abnormality (3), other malformation syndromes (4), renal dysplasia (1), laryngeal atresia (1) and severe fetomaternal haemorrhage (1). Five of the 40 fetuses survived, 2 treated antenatally for tachyarrhythmia, 2 had spontaneous resolution and the fifth fetus had repeated intrauterine transfusions because of human parvovirus B19-induced anaemia. After diagnosis of nonimmune hydrops fetalis, early referral to a tertiary centre is to be encouraged for investigation and provision of intensive perinatal care. Investigation allows parents to be counselled appropriately that the mortality is no longer 100% and a steadily growing number may be amenable to some form of fetal therapy.  相似文献   
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Tumor burden in adult patients with acute leukemia is assessed using the percentage of blast cells in the bone marrow or blood. It is clear, however, that not all blast cells are leukemic cells, especially during rapid marrow regeneration. Similarly, some leukemia cell lines have been shown to differentiate in vitro, and the same process also occurs in vivo. Therefore, the leukemic burden may be due to more differentiated cells as well as to blast cells. The purpose of this study was to investigate whether the human malignancy-associated nucleolar antigen (HMNA) could be used as a marker for leukemic cells and to examine its potential as a diagnostic tool. The proportion of HMNA-positive cells in the bone marrow of patients with acute leukemia was determined by indirect immunofluorescence with antibodies to HMNA and was compared with the differential counts routinely made in the clinic laboratory. The percentages of HMNA-positive cells among the nucleated cells in the marrow of 72 patients with clinical evidence of leukemia were significantly higher (range 9%-98%, median 83%) than those observed for nonleukemic individuals (range less than 0.05%-2.5%, median 1%) or for fractions of marrow cells from normal volunteers enriched for normal early progenitor cells (less than or equal to 2%). Patients with leukemia in remission had a lower percentage of HMNA- positive cells (range 0%-83%, median 3%). The percentage of HMNA- positive cells increased as patients approached relapse. Although the percentage of HMNA-positive cells was related to the percentage of blast cells in the bone marrow of the patients with leukemia, some partially differentiated cells were also HMNA-positive in some specimens, and some blastic cells were HMNA-negative in other specimens. These studies indicate the potential usefulness of HMNA as a marker for leukemic cells.  相似文献   
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