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91.
OBJECTIVE: Visual symptoms are common in patients with preeclampsia, and are caused by various underlying pathological changes in the retina. Blurred vision may be one of these symptoms. We describe three cases in which the underlying retinal pathology of blurred vision was clarified using optical coherence tomography (OCT), a novel, non-invasive ophthalmic imaging technique that provides micrometer-scale resolution images of the human retina. METHODS: Three patients with preeclampsia complained of blurred vision postpartum. In all cases, ophthalmoscopy was performed at the bedside, followed by the assessment of best corrected visual acuity, slit-lamp biomicroscopy, fluorescein angiography (FLA), and OCT. In all cases, the presence of central visual defects was examined by an Amsler-grid. RESULTS: In one case, the symptoms were bilateral. In all affected eyes, the patients complained of a relative central scotoma. Ophthalmoscopy showed edema in the affected maculae, while OCT examination clarified a serous neurosensory detachment of the macula. In one case, a neurosensory detachment was also detected in the papillomacular region of a fellow eye with no symptoms. In two cases, FLA was performed, but only in one case could we detect late leakage and subretinal exudates. The serous detachments observed showed total resolution in all cases within 5 to 10 weeks, with restoration of visual acuity. CONCLUSION: In patients with preeclampsia, OCT may provide a useful method for the precise assessment of retinal changes, distinguishing retinal edema from serous neurosensory detachments. This finding may help to clarify the pathophysiological circulatory changes seen in preeclampsia.  相似文献   
92.
OBJECTIVE: To assess which adverse postsurgical outcomes are best predicted by the Study on the Efficacy of Nosocomial Infection Control (SENIC) index and the National Nosocomial Infection Surveillance system (NNIS) index. DESIGN: Prospective cohort study. SETTING: The service of general surgery at a tertiary care hospital. PATIENTS: A consecutive series of patients hospitalized for more than 1 day (n=2,989). RESULTS: The outcome best predicted by the SENIC and NNIS indices was assessed by estimating the area under the receiver operating characteristic (ROC) curve. The areas under the ROC curves for nosocomial infection and in-hospital death were higher for the NNIS index than they were for the SENIC index (P<.05). The NNIS index predicted in-hospital death better than it predicted surgical site infection (area under the ROC curve+/-SE, 0.836+/-0.022 vs 0.689+/-0.017; P=.001). CONCLUSIONS: The NNIS index is superior to the SENIC index for all adverse postsurgical outcomes. Its ability to predict in-hospital mortality is clearly better than its ability to predict surgical site infection.  相似文献   
93.
就β-胡萝卜素立体异构体对环磷酰胺处理小鼠的免疫功能影响进行了比较研究。结果显示β-胡萝卜素立体异构体对外磷酰胺造成的免疫功能低下具有不同程度的改善作用,提高胸腺和脾脏指数,增强脾脏细胞对刀豆素A(ConA)的反应性和NK活性,血清溶菌酶含量也有所增加。综合各项指标,9-顺式和全反式混合物的作用最明显,提示一定浓度的9-顺式对于提高β-胡萝卜素对机体的总体作用是有一定意义的。  相似文献   
94.
The differences between the postprandial mixing or propulsion and the interdigestive motility of the gastrointestinal (GI) tract are already known. Earlier studies showed dose-dependent differences in the effects of erythromycin on interdigestive motility. The various GI side-effects (vomiting, diarrhoea) also suggest that there are different effects of erythromycin on the GI motility. The aim of our study was to examine postprandially the propulsive effects of different doses of erythromycin on the movement of intraluminal contents in the upper GI tract of the rat. The animals were fasted for 24 h before the experiments but water was given freely. The rats received 1.5 ml 1.5% methylcellulose painted with 0.05% phenol-red intragastrically (test solution). Erythromycin(E. lactobionate) was given intravenously at doses of 0.05, 0.1, 0.25, 0.5, 1.0 and 5.0 mg/kg 15 min before the administration of a test solution. The animals were sacrificed 20,60 and 120 min after administration of methylcellulose, when the distance between the front of the painted intraluminal contents and the pylorus was measured and expressed as a percentage of the total length of small intestine. The phenol-red content in the stomach and small intestine was measured spectrophotometrically and the gastric emptying was calculated from the ratio of the measured total and intestinal phenol-red content. Our results showed that the small doses of erythromycin (0.1 and 0.25 mg/kg) accelerated gastric emptying after 20 min but did not change significantly the propulsive motility of upper small intestine; however, large doses of erythromycin (1.0 and 5.0 mg/kg) decreased gastric emptying and upper GI motility after 20 and 60 min. In summary, the prokinetic action of small doses of erythromycin was demonstrated, but its effecttime on GI motility is short and the ratio of the stimulating and inhibitory doses is 1:10. This paper was presented at the Section of IUPHAR GI Pharmacology Symposium on ’Biochemical pharmacology as an approach to gastrointestinal disorders (basic science to clinical perspectives)‘, October 12-14, 1995, Pécs, Hungary.  相似文献   
95.
. Neutrophil-mediated tissue damage has been implicated in the pathogenesis of diarrhoea-associated haemolytic uraemic syndrome (D+ HUS). This study evaluates priming and activation of the neutrophil oxidative burst in D+ HUS using chemiluminescent techniques. Peripheral blood neutrophils from 11 children with acute D+ HUS were examined. No difference was found in the oxidative burst of neutrophils from patients and controls. Serum elastase levels were measured in 8 patients and found to be significantly elevated. Although elastase results suggest neutrophil activation, chemiluminescence studies do not confirm this in the peripheral blood neutrophil. This does not support a significant role for circulating agents in priming and activating the peripheral blood neutrophil. Received August 17, 1995; received in revised form and accepted November 27, 1995  相似文献   
96.
Twenty-eight members of the general public, with little nutritional knowledge and no previous commitment to dietary change, completed 7-day-weighed dietary diaries. They then attempted to change their diets, where appropriate, in line with current nutritional guidelines.
The panel achieved changes in diet that were consistent with the recent recommendations but several problems arose. In particular, although fat levels were reduced, energy levels fell and fibre goals were not reached; in addition, certain of the initial vitamin and mineral intakes gave cause for concern. These results emphasize the importance of giving advice not only about foods that might be reduced in the diet, but also about food that might be used as alternatives. They also illustrate the difficulty of persuading people to make radical changes to their eating habits even when given personal advice from a nutritionist.
The panel was small and not necessarily representative, but the results illustrate the need for more dietary analysis studies. It is not enough simply to formulate appropriate guidelines from a nutritional point of view; it is also important to ensure that the public understands them and that people make sensible decisions about their diet.  相似文献   
97.
Effects of the MAO-A-inhibitor brofaromine (BRO), 10 mg/kg po after repeated (twice daily for 14 days) administration on the spontaneous behavior (exploratory and basal locomotor activities) and the exploratory activity modified by methoxamine, clonidine and d-amphetamine in male Wistar rats were studied in both light and dark phases of a diurnal cycle (L: 0700-1900 h). After single administration BRO in the light phase had no effects. In the dark phase BRO decreased the exploration (62% of control, p less than 0.01), increased the clonidine-evoked hypoactivity and amphetamine-evoked hyperactivity. The L-D differences occurred also after repeated administration. BRO in the light phase did not influence the exploration, decreased basal locomotor activity, did not change methoxamine and clonidine action and potentiated the action of amphetamine. In the dark phase, however, it did not influence the exploration and basal locomotor activity, intensified the methoxamine effect, and did not change the clonidine and amphetamine actions. The results demonstrate that the effects of BRO on behavior in rats: 1) differ from the effects caused by other antidepressants which are not MAO inhibitors; 2) are phase-dependent after both single and repeated administration.  相似文献   
98.
BACKGROUND: Catheter hub contamination is being increasingly recognized as a source of catheter-related sepsis. The authors have investigated the efficacy of a new hub design in preventing endoluminal catheter contamination and catheter-related sepsis arising at the hub. METHODS: Adult surgical and intensive care patients requiring a subclavian catheter for at least 1 week were randomly assigned to receive catheters with standard connectors (control group, n=73) or equipped with a new hub model (new hub group, n=78). Skin, catheter tip, and hub cultures were performed at the time the catheter was withdrawn because therapy was terminated or because of suspicion of sepsis, in which case peripheral blood cultures were taken. RESULTS: Of the 151 patients included, 15 (10%) developed catheter-related sepsis. Catheters were more often withdrawn because suspicion of infection in the control group (42 vs. 19%, p<0.005). Catheter sepsis rate was higher in the control group (16 vs. 4%, p<0.01) because of the low rate of catheter sepsis arising at the hub observed in the new hub group (1 vs. 11%, p<0.01). The prevalence of culture-positive catheter hubs without associated bacteremia (colonization) was higher in the control group (18 vs. 5%, P<0.03). CONCLUSIONS: A new catheter hub has proved to be useful in preventing endoluminal bacterial colonization and catheter-related sepsis in subclavian lines inserted for a mean of 2 weeks.  相似文献   
99.
100.
During the development of motor vagal nuclei (MVN), the neuroblasts of the myeloencephalic basal plate migrate in the dorsolateral direction to form the dorsal motor vagal nucleus (DMVN) and ventrolaterally to form the ventral motor vagal nucleus (VMVN). Those neuroblasts that remain close to the median sulcus will form the hypoglossal nucleus. In support of the congenital origin of the alteration of the MVN in sudden infant death syndrome (SIDS), we report the case of an 8‐month‐old female child who was found dead in her cot. The neuropathological assessment revealed that the medullary triangle of the 4th ventricle floor was asymmetric, owing to the presence of three prominences to the left side of the median sulcus. The medial prominence corresponded to the hypoglossal nucleus, which showed a marked increase in the number of large neurons; the intermediate prominence corresponded to the DMVN whose large neurons were reduced and were recognizable mainly at the level of the medial fringe; the lateral prominence corresponded to the solitary nucleus. The left solitary tract showed a reduction of the transverse diameter. Also, the left VMVN showed marked reduction in the number of neurons. Inflammatory and astrocytic reactions were absent. We suggest that in SIDS cases the hypocellularity of the MVN and the increased number of neurons of the hypoglossal nucleus are intimately related, indicating a congenital alteration due to incomplete migration of the vagal neuroblasts with abnormality of the autonomic cardio‐respiratory control.  相似文献   
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