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991.
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B Cady CE Sedgwick WA Meissner JR Bookwalter V Romagosa J Werber 《Canadian Metallurgical Quarterly》1976,184(5):541-553
Records of 792 patients with differentiated thyroid carcinoma seen at the Lahey Clinic Foundation over a 40-year period were analyzed; 631 patients had a minimum followup period of 15 years. Differentiated types currently constitute nearly 90% of thyroid carcinomas. The clinical presentation has improved substantially through the years, and the results of treatment generally have improved. The per cent of patients with primarily incurable and locally unresectable disease or distant metastases has decreased from 7% before 1950 to 1% currently, and this group resulted in almost one third of the total fatalities and one half of fatalities within the first 5 years after treatment. Clear relationships were demonstrated between older age, men, extraglandular extension, blood vessel invasion, major capsular involvement, multifocal disease, and higher mortality rates. Lymph node metastases were found to exert a protective effect in all categories of disease analyzed, and this effect was directly related to the number of lymph node metastases present such that no deaths occurred in those patients who had more than 10 node metastases. Surgical treatment recommended is subtotal thyroidectomy for patients at high risk of death from disease as defined by combinations of age, sex, and extraglandular extension. Patients at low risk or with small carcinomas can be treated satisfactorily by lobectomy. Lymph node resections should be of a limited type or a modified neck dissection and should be performed only therapeutically. No improvement, as judged by mortality or recurrence rates, could be demonstrated by the use of radio therapy after surgery, and its use should be discouraged. Thyroid hormone administered for suppression of endogenous thyroid-stimulating hormone production improved mortality rates significantly in patients with papillary and mixed forms of carcinoma in all age groups but did not affect survival in patients with follicular carcinoma of the thyroid.20 相似文献
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Newborn A, C57BL, DBAf and IF mice were injected s.c. with a range of doses of N-ethyl-N-nitrosourea (ENU). A high proportion of treated mice developed tumours, particularly hepatomata, pulmonary adenomata and carcinomata, and malignant lymphomata of thymus and spleen. Liver tumours occurred most frequently in C57BL and DBAf mice, lung tumours in A mice, and lymphomata in A and DBAf mice. A small proportion of C57BL, DBAf and IF mice developed tumours of the nervous system. The results are discussed with reference to the ready induction of nervous system tumours in similarly treated rats, and their relevance for human cancer. 相似文献
997.
Employee perceptions of the fairness and accuracy of a performance evaluation system were examined by means of a questionnaire administered to all exempt managerial and professional employees of a large manufacturing organization. Primary (N?=?355) and hold-out (N?=?356) samples were identified, and a forward stepwise multiple regression analysis was performed on the primary sample. Cross-validation indicated that a 5-variable linear composite accounted for 29% of the variance in the dependent variable. Frequency of evaluation, identification of goals to eliminate weaknesses, and supervisor knowledge of a subordinate's level of performance and job duties were significantly related to perceptions of fairness and accuracy of performance evaluation. (3 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
HP Gutgesell CE Mullins PC Gillette M Speer AJ Rudolph DG McNamara 《Canadian Metallurgical Quarterly》1976,89(1):120-125
Three newborn infants with congestive heart failure had hemodynamic, angiographic, and echocardiographic features of hypertrophic subaortic stenosis (hypertrophic obstructive cardiomyopathy). Treatment with digitalis and diuretic drugs was ineffective, but improvement occurred when these agents were withheld in one patient, and when treatment with propranolol was begun in two patients. Echocardiography was helpful in establishing the diagnosis in two patients and showed resolution of the condition during the first six months of life. Serial cardiac catheterizations confirmed resolution of the outflow obstruction in the third patient. Family studies revealed no evidence of familial cardiomyopathy, but the mothers of two infants had insulin-dependent diabetes mellitus and the mother of the third was presumed to be prediabetic. 相似文献
999.
HP Baden CE Jackson L Weiss K Jimbow L Lee J Kubilus RJ Gold 《Canadian Metallurgical Quarterly》1976,28(5):514-521
The physicochemical properties of hair from a new recessive syndrome associated with brittle hair, intellectual impairment, decreased fertility, and short stature have been studied. Electrophoresis of the SCM-structural proteins showed that the alpha polypeptides appeared normal, but the matrix component was markedly reduced. This was confirmed by finding a normal alpha X-ray diffraction pattern but a reduced 1/2 cystine content of hair and an abnormal stress-strain curve. Electron-microscopic studies revealed extreme disorganization of the filaments which most likely resulted from the absence of normal cross-linking. Nails, which contain structural proteins similar to hair, also showed the abnormality. Since the matrix component seen by electrophoresis consists of more than one component the defect cannot be explained as a single structural gene abnormality. 相似文献
1000.
The detection statistics of a molecular beam are analyzed, taking into account fluctuations in emission, transition and detection. It is discovered that the over-all process has a Poisson distribution. Because of the nature of this distribution, it is noted that the optimum method of estimating the average number of molecular transitions is by means of a long-time average of the detected current. The degree to which the detector current is a measure of the average number of molecular transitions in the device is established, with a certain minimum confidence, by use of the Tchebycheff Inequality. 相似文献