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排序方式: 共有619条查询结果,搜索用时 15 毫秒
1.
Transvaginal ultrasound measurements of the fetal heart at 11 to 17 weeks of gestation. 总被引:2,自引:0,他引:2
The scope of this article is to report on transvaginal ultrasound measurements of the fetal heart, which were performed in 124 healthy fetuses at 11 to 17 weeks of gestation. Normative growth charts were constructed. Statistical analysis demonstrated linear correlation (y = a + bx) between gestational age and measurements of the right and left ventricles. The ratio between fetal heart and the transverse diameter of the chest was found to be nearly constant at these gestational ages. 相似文献
2.
E L Siegler L Taylor R Norris K Jedrziewski N Reichek 《Archives of physical medicine and rehabilitation》1992,73(8):730-734
In a prospective blinded trial, 24-hour continuous electrocardiographic monitoring for silent ischemia was used to try to identify rehabilitation patients at risk for cardiac complications. Five of 42 patients had episodes of silent ischemia, none of which occurred during physical therapy sessions. One of these patients had syncope while wearing the Holter; none of the other four patients had significant cardiac complications during their rehabilitation, and all were discharged home. None of the patients without ischemia on the monitor had complications, but two patients of 14 whose ECGs precluded monitoring for ischemia had complications. In addition, six patients had episodes of nonsustained asymptomatic ventricular tachycardia, 12 had episodes of supraventricular tachycardia, and four had significant ventricular ectopy, all without clinical significance. Despite the apparent high sensitivity and specificity of the technique, the positive predictive value of monitoring eligible patients for silent ischemia was 20%. We conclude that ambulatory electrocardiographic monitoring for silent ischemia or ectopy has limited clinical utility in the rehabilitation population. 相似文献
3.
'Doctors must not kill' 总被引:2,自引:0,他引:2
Four physicians respond to "It's over, Debbie," an anonymous resident physician's account of an incident when he or she injected a terminally ill cancer patient with a lethal dose of morphine (JAMA 1988 Jan 8; 259(2): 272). Gaylin and his colleagues condemn both the physician's violation of legal and ethical norms, and the conduct of JAMA's editor in publishing the article without editorial rebuke or comment. They warn that the issue of active euthanasia "touches medicine at its very moral center," and that, as pressure to legalize euthanasia in response to patient demand increases, the medical profession must repudiate direct and intentional killing of patients and discipline doctors who kill. 相似文献
4.
Dichlorotriazinylaminofluorescein (DTAF) has been proposed as a fluorescent derivatising agent for secondary aliphatic amines. In this report, its applicability as a pre-column reagent is demonstrated by its use in the analysis of aqueous solutions and plasma samples of the tricyclic antidepressant, desipramine. Samples were processed by liquid-solid extraction onto XAD-2 resin, followed by DTAF derivatisation of the fraction of the column effluent containing analyte. The reaction mixture was then subjected to HPLC using a dual column switching configuration that was designed to (a) separate excess DTAF from the reaction product, and to (b) achieve the necessary analytical resolution. Fluorometric detection of the analyte in column effluent afforded a sensitivity of 150 fmol of desipramine injected on-column, a 2-3 order of magnitude increase in sensitivity relative to previously described methods. DTAF appears to be a convenient reagent for fluorescence derivatisation of N-methyl secondary amines prior to their HPLC analysis. 相似文献
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AIMS: Epstein-Barr virus (EBV) immortalises B cells in vitro and is associated with several malignancies. Most phenotypic effects of EBV are mediated by latent membrane protein 1 (LMP1), which interacts with tumour necrosis factor receptor associated factors (TRAFs) to activate NF-kappaB. This study examines TRAF1 and LMP1 expression in EBV associated lymphoproliferations. METHODS: TRAF1 expression was investigated in 26 Hodgkin lymphomas (HL; 18 EBV+, eight EBV-), seven EBV+ Burkitt lymphomas (BL), two infectious mononucleosis (IM) tonsils, and lymphoreticular tissue from eight chronic virus carriers. Seven anaplastic large cell lymphomas and 10 follicular B cell lymphomas were also studied. Colocalisation of TRAF1 and LMP1 was studied by immunofluorescent double labelling and confocal laser microscopy. RESULTS: TRAF1 colocalises with LMP1 in EBV infected cells in IM. EBV positive lymphocytes from chronic virus carriers were negative for TRAF1 and LMP1. In HL biopsies, TRAF1 was strongly expressed independently of EBV status, whereas all BL cases were TRAF1-. In EBV+ HL cases, TRAF1 colocalised with LMP1. Eight of 10 follicular lymphomas expressed TRAF1 in centroblast-like cells. Four of seven anaplastic large cell lymphomas weakly expressed TRAF1. CONCLUSIONS: These results suggest that in non-neoplastic lymphocytes, TRAF1 expression is dependent on the presence of LMP1, and that in IM B cells in vivo, LMP1 associated signalling pathways are active. In HL, TRAF1 is expressed independently of EBV status, probably because of constitutive NF-kappaB activation. The function of TRAF1 in HL remains to be determined. 相似文献
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Die Anaesthesiologie - 相似文献
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N.V. Jaumard J.K. Udupa S. Siegler J.M. Schuster A.S. Hilibrand B.E. Hirsch A. Borthakur B.A. Winkelstein 《Medical hypotheses》2013
For some patients with radiculopathy a source of nerve root compression cannot be identified despite positive electromyography (EMG) evidence. This discrepancy hampers the effective clinical management for these individuals. Although it has been well-established that tissues in the cervical spine move in a three-dimensional (3D) manner, the 3D motions of the neural elements and their relationship to the bones surrounding them are largely unknown even for asymptomatic normal subjects. We hypothesize that abnormal mechanical loading of cervical nerve roots during pain-provoking head positioning may be responsible for radicular pain in those cases in which there is no evidence of nerve root compression on conventional cervical magnetic resonance imaging (MRI) with the neck in the neutral position. This biomechanical imaging proof-of-concept study focused on quantitatively defining the architectural relationships between the neural and bony structures in the cervical spine using measurements derived from 3D MR images acquired in neutral and pain-provoking neck positions for subjects: (1) with radicular symptoms and evidence of root compression by conventional MRI and positive EMG, (2) with radicular symptoms and no evidence of root compression by MRI but positive EMG, and (3) asymptomatic age-matched controls. Function and pain scores were measured, along with neck range of motion, for all subjects. MR imaging was performed in both a neutral position and a pain-provoking position. Anatomical architectural data derived from analysis of the 3D MR images were compared between symptomatic and asymptomatic groups, and the symptomatic groups with and without imaging evidence of root compression. Several differences in the architectural relationships between the bone and neural tissues were identified between the asymptomatic and symptomatic groups. In addition, changes in architectural relationships were also detected between the symptomatic groups with and without imaging evidence of nerve root compression. As demonstrated in the data and a case study the 3D stress MR imaging approach provides utility to identify biomechanical relationships between hard and soft tissues that are otherwise undetected by standard clinical imaging methods. This technique offers a promising approach to detect the source of radiculopathy to inform clinical management for this pathology. 相似文献