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排序方式: 共有1998条查询结果,搜索用时 0 毫秒
921.
Twelve cases of optic nerve glioma seen over a 28 year period are analysed herein in this autopsy study. 相似文献
922.
923.
924.
Fusion of the nucleoporin gene NUP98 to HOXA9 by the chromosome translocation t(7;11)(p15;p15) in human myeloid leukaemia 总被引:1,自引:0,他引:1
T Nakamura DA Largaespada MP Lee LA Johnson K Ohyashiki K Toyama SJ Chen CL Willman IM Chen AP Feinberg NA Jenkins NG Copeland JD Shaughnessy 《Canadian Metallurgical Quarterly》1996,12(2):154-158
The parasympathetic nervous system plays a major role in the pathophysiology of many cardiovascular disease, particularly in modulating myocardial electrical stability. Measurements of heart rate variability have been widely used to assess parasympathetic activity. The reproducibility of measurements obtained from 24-hour ambulatory electrocardiograms has not been well documented. We have developed a technique for measuring parasympathetic activity from clinical quality 24-hour ambulatory electrocardiograms by counting beat-to-beat increases in RR interval that are > 50 ms. To determine the reproducibility and sensitivity of our technique, we analyzed repeated 24-hour electrocardiograms of 173 subjects (19 normal subjects, 67 patients with ischemic heart disease, and 87 diabetics) followed up over periods of 2 to 16 weeks. In all subject groups, mean values for repeated measurements were virtually identical. Measurements were stable in all 3 groups throughout the course of the study, as assessed by intraclass correlation coefficients. This technique is sensitive enough to detect relatively small changes in parasympathetic activity in subjects, as demonstrated by the calculated Bland and Altman coefficients of repeatability. Reproducibility and sensitivity of our technique are particularly good in normal subjects and in patients with ischemic heart disease. The results obtained with this technique imply that other related measurements of parasympathetic activity will show similar excellent short- and long-term reproducibility and sensitivity. 相似文献
925.
926.
PM Rathi A Soni SA Nanivadekar P Sawant MS Bhatnagar AP Upadhyay 《Canadian Metallurgical Quarterly》1996,23(3):228-231
Vascular dementia is actually considered as a ill-defined entity. The clinical and neuropathologic criteria of this multifactorial disorder remain uncertain. Although not widely accepted, the introduction of the concept of incomplete infarction in the brain can help to explain some particular types of vascular dementia. In the hypoxic-hypoperfusion dementia syndromes of cerebral cortex and white matter and in lacunar state dementia, which are the most common types of vascular dementia, areas of incomplete infarction co-exist with regions of complete infarction. Although initially rejected by early positron emission tomographic studies, it can now be demonstrated that these incomplete infarction areas reflect chronic ischaemia of the brain and that they are relevant to the pathogenesis of vascular dementia. 相似文献
927.
Video assisted thoracoscopic drainage and tale pleurodesis was used to treat a recurrent pleural effusion in a 60 year-old woman undergoing major gynecologic surgery. She developed reexpansion pulmonary edema immediately following surgery. Several important risk factors that were present in this patient are discussed. In addition to almost, complete collapse of the underlying lung for several weeks, thoracoscopy resulted in manipulations and rapid re-inflation of the underlying lung, which further increased the risk to the patient. 相似文献
928.
OA Odukoya A Bansal P Wilson K Lim AP Weetman ID Cooke 《Canadian Metallurgical Quarterly》1996,11(9):2018-2021
Activated B cells are known to produce soluble CD23 protein (sCD23) from their membranes. We recently showed a higher concentration of sCD23 in the serum of patients with endometriosis. As the commonest site of endometriosis is the peritoneal cavity, we sought to evaluate the concentration of sCD23 in the peritoneal fluid of 47 fertile symptomatic women with endometriosis and 35 fertile women without endometriosis. Endometriosis was diagnosed by laparoscopy and confirmed by histopathology. There was a statistically significant difference between the sCD23 concentrations in the endometriosis and control groups (P < 0.05). When endometriosis was defined based on the revised American Fertility Society (AFS) Score, patients with mild (AFS 1 and II) but not severe (AFS III and IV) endometriosis showed a higher and significant difference in the concentration of sCD23 when compared with the controls (P < 0.05). There was no significant correlation between the peritoneal fluid concentration of sCD23 and the phase of the menstrual cycle. We conclude that the concentration of sCD23 is higher in the peritoneal fluid of patients with endometriosis when compared with the controls, suggestive of B cell activation in patients with endometriosis. Furthermore, mild endometriosis is immunologically more active than severe endometriosis as defined by the current classification. 相似文献
929.
D Van Gysel AP Oranje I Vermeiden J de Lijster de Raadt PG Mulder AW van Toorenenbergen 《Canadian Metallurgical Quarterly》1996,35(4):556-558
BACKGROUND: Histamine is an indicator of mast cell activation. N-methylhistamine (NMH) is a metabolite of histamine that can be measured in urine. OBJECTIVE: Our purpose was to assess the usefulness of determining urinary NMH levels for the diagnosis and follow-up of patients with mastocytosis. METHODS: Urinary NMH levels were determined in 44 patients and were correlated with disease activity and extension. The control group consisted of 24 children without mastocytosis or any other skin disease. RESULTS: A significant negative correlation was found between NMH and age in patients with active mastocytosis and in the control group. Adjusted for age, NMH values were significantly higher in patients with active mastocytosis. There was a significant difference in NMH values between patients with diffuse cutaneous mastocytosis, patients with active urticaria pigmentosa, and patients with active mastocytomas. However, there was a substantial overlap of NMH values in the different subgroups. CONCLUSION: Urinary NMH values tend to decrease with age. Urinary NMH values correlated with the extent and the activity of the disease. High NMH values suggest more extensive involvement. 相似文献
930.
AI Korzan TI Samoylova II Protas MB Rozhdestvenskaya SI Borisevich AP Nikodov LI Zlotkin 《Canadian Metallurgical Quarterly》1996,41(1):28-34
BACKGROUND: Lens adherence and a reduced postlens tear film circulation have been suggested as factors contributing to some adverse reactions in extended wear of hydrogel contact lenses. In this study, we determined lens fitting and postlens tear film characteristics during closed-eye wear. METHODS: Twenty subjects wore hydrogel lenses for 3 h of eye closure, followed by 30 min of open-eye wear. Lens movement was measured with a video biomicroscope. Postlens tear film appearances in specular reflection were classified as either amorphous, or as one of four color intensity grades, where a colored appearance was taken as indicative of a depleted postlens tear film. RESULTS: All subjects showed lens adherence (movement < 0.1 mm) and postlens tear film depletion within 45 min of eye closure. These changes were sustained for the remainder of the closed-eye period, but were reversed within 15 min of eye opening. Lens adherence was associated with colored postlens tear film patterns of any intensity. CONCLUSION: Closed-eye wear was invariably associated with the onset of lens adherence and postlens tear film depletion. This finding emphasizes the need for adequate lens movement during the open-eye phase of extended wear. 相似文献