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61.
A 28-year-old woman was admitted to our Hospital with a chief complaint of progressive gingival swelling and loosening of teeth over about a year. According to past history, she had received total thyroidectomy 2 years previously due to thyromegaly. The thyroidectomy specimen was at first interpreted as 'poorly differentiated carcinoma of the thyroid'. One year ago, she began to be aware of gingival swelling and loosening of teeth. A gum biopsy was taken and the pathologic features were similar to her 'thyroid carcinoma'. Subsequent investigations, including immunohistochemical stain, showed the gum was heavily infiltrated with histiocyte-like Langerhans' cells which were positive for S-100 protein. Ultrastructural examination of the cells under electron microscope revealed many typical intra-cytoplasmic Birbeck granules. Langerhans' cell histiocytosis was diagnosed. Langerhans' cell histiocytosis with thyroid involvement is extremely rare and may run a relatively indolent course. Even on a retrospective examination, it may easily be confused with poorly differentiated carcinoma of the thyroid. We suspect that this error may have been made on other occasions and that the occurrence of this condition may be underreported.   相似文献   
62.
Histidinaemia is a relatively common inherited metabolic disorder with an incidence similar to phenylketonuria. This paper reports the long term outcome of patients diagnosed by newborn screening in the north west of England. Between 1966 and 1990, 108 infants were diagnosed as having histidinaemia by a regional neonatal screening programme (incidence 1:11,083). A further five children were detected following diagnosis in a sibling. Of the 113, nine were lost to follow up. Infants diagnosed before 1981 (n = 47) were placed on a low histidine diet (225 mg/kg/d) for an average period of 21 months (SD 4.5). All patients were reviewed regularly, Griffiths developmental quotients (DQ) were assessed at 2 and 4 years, and WISC-R intelligence quotients (IQ) at 8, 12, and 18 years. IQ data were converted to standard deviation scores (IQ SDS) to account for increasing IQ norms with time. Neither DQ nor IQ correlated with plasma histidine at diagnosis or with the mean plasma histidine throughout life. Growth was normal in all patients. There was no apparent benefit from a low histidine diet in early childhood. In contrast to other studies, there was no excess of clinical symptoms. On the basis of these findings, histidinaemia is a benign metabolic disorder that does not require treatment.  相似文献   
63.
Lingual thyroid gland: sonographic appearance   总被引:1,自引:0,他引:1  
Miller  JH 《Radiology》1985,156(1):83-84
Thyroid dysgenesis is often manifested by a lingual or sublingual location of the thyroid gland. If radionuclide studies are not readily available or are contraindicated, ultrasound (US) may be used to locate the gland. The US appearance of a lingual thyroid gland and the role of US in the evaluation of suspected thyroid dysgenesis are described.  相似文献   
64.
65.
Concepts necessary to an understanding of the basics of quality assurance audits are presented. Included are specific examples that bridged theory and practice by applying the protocol to a real-life diagnostic imaging situation. This method meets the present requirements of the Joint Commission of the Accrediation of Hospitals.  相似文献   
66.
Lasser  EC; Lang  JH; Lyon  SG; Hamblin  AE; Howard  MM 《Radiology》1981,140(1):11-15
An in vitro is described that attempts to detect patients with a potential for adverse systemic reactions to contrast material. This test involves measuring the rate of conversion of prekallikrein to kallikrein under certain standard conditions. In a preliminary retrospective study, the test could be used to identify such patients with a sensitivity of 88%, a specificity of 82%, and a predictive value of 79%.  相似文献   
67.
Yum MK  Kim JH 《Pediatric research》2003,53(6):915-919
We noticed that fetal heart rates (FHR) of immature fetuses intermittently showed unstable sudden and brief falls below baseline FHR that occur over a few or several heartbeats. The frightening falls do not occur in mature fetuses. In nonlinear dynamics, the degree of such abrupt falls in time series is quantified as intermittency. We aimed to investigate the nature and maturational changes of intermittency of the FHR in normal fetuses and to present the intermittency values of normal fetuses according to gestational weeks. FHR data of 450 normal fetuses between 23 and 40 wk of gestation were studied. We performed multifractal analysis and highlighted a very-short-term intermittency (C1alpha, 4 相似文献   
68.
The extracellular part of ErbB-2 is formed by 4 domains, specifically, L1, L2 that adopt a beta-helical structure and S1, S2 that consist of several cysteine-rich, EGF-fold modules. These ectodomains mediate ErbB-2 dimerisation with itself or with other members of the epidermal growth factor receptor (EGFR) family, events essential to both ErbB-2 signaling and the development of certain malignancies. The anti-ErbB-2 monoclonal antibodies N12, N28 and L87 bind to the polypeptides C531-A586, T216-C235 and C220-C235 respectively. In this study, glycine walking and random mutagenesis were used to further delineate the critical residues involved in antibody binding. A molecular model of ErbB-2 ectodomains was then constructed based on the recently published coordinates of the EGFR (EGFR) model. This model rationalized successfully many features of our epitope mapping, including their location in modules within the S1 and S2 domains and the importance of Arg545, Gln548 and Leu561 for N12 binding. Further investigation of the functional effects of the anti-ErbB-2 monoclonal antibodies demonstrated that N28 strongly stimulated ErbB-2 phosphorylation and MAPK activation whereas N12 had no effect. As bivalency is required for the action of these antibodies we propose that at least 2 different kinds of ErbB-2 homodimers can be formed as relative rotational isomers and that the S1 and S2 domains are instrumental in determining the relative orientations of the ErbB-2 homodimers, such that different signaling effects are induced.  相似文献   
69.
To investigate change of cardiac autonomic activity and cardiac complexity during general anesthesia in hypertensive patients, we analyzed electrocardiographic (ECG) data using power spectral analysis and approximate entropy (ApEn). Anesthesia was performed by a mixture of enflurane and nitrous oxide. From 10 minutes before induction of anesthesia(resting state) until 20 minutes after induction, ECG data were obtained from newly diagnosed and untreated hypertensive (n = 18) and normotensive patients (n = 18). Period 1 was defined as the initial 10 minutes after induction and period 2 as the following 10 minutes. The low-, mid-, and high-frequency power and the values of ApEn of the two groups were calculated from ECG recording. At resting state, the powers in all frequency bands and the values of ApEn in hypertensive patients did not differ from those of normotensive patients. During periods 1 and 2, the powers of all frequency range significantly decreased in normotensive group (p<0.05), while they did not change in hypertensive group. The values of ApEn in normotensive patients decreased significantly only during period 2, while those in hypertensive patients decreased during periods 1 and 2 (p<0.05 and p<0.05, respectively). These results suggest that, in the hypertensive patients, persistent autonomic activity under the condition of suppressed cardiac complexity may contribute to the unstable hemodynamic insults from the outset of general anesthesia.  相似文献   
70.
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