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61.
Traditional and immunohistochemical markers of prognosis were examined in 455 mammary carcinomas derived from breast cancer screening and compared with those of 277 carcinomas presenting symptomatically over the same period. Tumours detected by population screening under the U.K. National Health Service Programme do not differ from those detected by other screening projects, but compared with symptomatic cancers, screen-detected cancers are more likely to be in situ and if invasive, to be smaller, of lower grade, and to have invaded vessels, perineural spaces, and lymph nodes less frequently. Tubular and cribriform types are more often represented in screened patients. Immunohistochemical markers which have been proposed as being related to likely tumour behaviour (epidermal growth factor receptor, c-erbB-2 protein, oestrogen and progesterone receptors, cathepsin D, p53, and retinoblastoma protein) do not distinguish screen-detected from ‘clinical’ cancers. It is concluded that cancers diagnosed at screening do not differ biologically from those presenting clinically, but are the same lesions detected at an earlier stage of their natural history. © 1997 John Wiley & Sons, Ltd.  相似文献   
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Because many diabetic patients in the United Arab Emirates use medicinal plants as a supplement to treatment with insulin or oral hypoglycaemic agents, the effect on plasma glucose, insulin and glucagon concentrations of simultaneous treatment of streptozotocin-diabetic rats with Rhazya stricta extract and glibenclamide has been examined. Treatment of control rats with the extract at oral doses of 0.5, 20 and 4.0 g kg? did not significantly affect the concentration of glucose, insulin or glucagon for up to 4 h after administration of the extract. The same doses in diabetic rats reduced the glucose level 1 h (2 and 4 gkg?) and 2h (4 gkg?) after administration of the extract. This was accompanied by significant increases in insulin concentration 1, 2 and 4 h after administration of the extract at doses of 2 and 4 gkg?. Glibenclamide (2.5, 5.0 and 10.0 mgkg?) dose-dependently reduced glucose and glucagon levels, and increased that of insulin in normal and diabetic rats. Simultaneous treatment of normal and diabetic rats with the plant extract (0.5, 20 and 5.0 gkg?) and glibenclamide (5.0 mg kg?) significantly exacerbated the effects on glucose, insulin and glucagon induced by the extract or by glibenclamide when given separately. When the plant extract was given at doses of 0.5, 2 and 4 g kg? per day for 6 consecutive days the glucose level was reduced by approximately 6, 8 and 30%, respectively. No significant effect was seen on the levels of cholesterol or protein. These results imply that co-administration of the extract with glibenclamide might adversely interfere with glycaemic control in diabetic patients.  相似文献   
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Background: Several studies have reported that hyperthyroidism is associated with prolonged QT interval corrected by the heart rate (QTc) and pulmonary hypertension (PHT). Methods: Forty‐seven patients with newly diagnosed overt hyperthyroidism and 20 healthy people were enrolled in the study. Transthoracic echocardiography, 12‐lead surface electrocardiogram, and thyroid hormone levels were studied at the time of enrollment and after achievement of euthyroid state with propylthiouracil treatment. Results: Baseline clinical characteristics were similar. However, heart rate (90.5±19.6 vs 79.2±13.7 bpm, P = 0.024), pulmonary artery systolic pressure (PASP) (26.0±12.0 vs 10.6±4.0 mmHg, P < 0.001), E deceleration time (DT) (191.8±25.6 vs 177.0±10.7 ms, P = 0.016), isovolumetric relaxation time (IVRT) (91.38±12.3 vs 79.6±10.5 ms, P < 0.001), and QTc dispersion (QTcD) (50.3±17.2 vs 38.9±11.6 ms, P = 0.009) were significantly higher in hyperthyroid patients compared to control group. Heart rate (to 74.1±13.8, P < 0.001), QTcD (to 37.3±10.1 ms, P < 0.001), DT (to 185.3±19.7 ms, P = 0.008), IVRT (to 88.6±10.3 ms, P = 0.056), and PASP (23.1±10.1 mmHg P < 0.001) were significantly decreased after achievement of euthyroid state. Although PHT was present in 16 patients before treatment only six patients still had PHT during euyhyroid state. Compared to patients with normal PASP, QTcD was significantly longer in patients with PHT (56.5±15.8 vs 37.9±12.8 mmHg P < 0.001). There were also significant correlations between QTcD and presence of PHT (r = 0.516, P < 0.001) and PASP (r = 0.401, P = 0.009). Conclusions: Hyperthyroidism is a reversible cause of PHT and diastolic dysfunction. Increased QTcD observed in hyperthyroidism may be associated with PHT and diastolic dysfunction. These abnormal findings in hyperthyroidism often normalize with the achievement of euthyroid state.  相似文献   
66.
Background: The determination of early, accurate, predictive criteria for a positive result would permit a reduction in the duration of the head‐up tilt testing (HUTT). Previous studies propounded that existence of early sympathetic overreactivity (rapid and sustained increase in heart rate) during HUTT predicts positive result. However, the exact value of this variable is unknown. We analyzed the early heart rate (HR) responses to HUTT and evaluated their ability to predict HUTT result. Methods: Consecutive patients referred to the syncope unit of our center for recurrent unexplained syncope were studied. Results: We studied 189 consecutive patients and 67 (35%) patients had a negative HUTT; 122 (65%) patients had a positive HUTT. The early HR increase was defined as the maximum HR during the first 10 minutes of tilting minus the resting HR before tilting. The receiver–operator curves (ROCs) show the overall performance of the HR changes for predicting the HUTT result. For all variables, area under the ROC curve (AUC) was nearly equivalent to 0.50 and early HR increase was not a predictor of the negative result of HUTT (AUC = 0.546). Also there was no any significant correlation between the magnitude of early HR increase and patient age (r =?0.03, P = 0.76). Conclusions: The results suggest that the early increase in HR during the first 10 minutes of the HUTT may not be a useful parameter for predicting the test result. Many factors, such as late exaggeration in sympathetic activity during HUTT and age‐dependent reduction in baroreflex sensitivity, may attenuate the predictive value of early HR increase. (PACE 2010; 33:153–158)  相似文献   
67.
概述:心因性抽搐发作经常会漏诊,并且癫痫往往会被过度治疗从而导致多种财力、社会、以及耻辱感相关的问题。肌阵挛癫痫发作本身是一种罕见的现象,当功能性运动障碍呈现肌阵挛的时候就极难找到确切的原因。在这里,我们呈现一个被误诊为肌阵挛癫痫发作障碍的病例,该患者在多处经过治疗却无好转并且最终被诊断为患有非常罕见的功能性运动障碍。  相似文献   
68.
Adult male turkeys were treated orally with furazolidone at doses of 1, 2.5, S or 20 mg/kg for 14 days and their plasma analysed for luteinizing hormone (LH), testosterone and prolactin (PRL) concentrations before, during and after treatment. At 20 mg/kg the drug produced a significant decrease in the plasma levels of LH and testosterone at the end of treatment, whereas at 5 mg/kg the drug had no significant effect. Prolactin concentrations were unaffected by any of the drug doses used. Intramuscular injection of luteinizing hormone releasing hormone (LHRH) at a dose of 5 μg/kg produced after 30 min a significant rise in plasma levels of LH, an effect that was decreased significantly by treatment with 20 mglkg furazolidone. Incubation of normal turkey semen with graded doses of furazolidone or nitrofura-zone for up to 30 min resulted in a dose- and time-dependent decrease in sperm motility. At a concentration of 20 mg/ml a complete absence of sperm motility was observed after incubation with either drug, although, on the whole, nitrofurazone seemed more potent than furazolidone as a sperm-immobilizing agent. Histological changes occured in the 20 mg/kg group and consisted of a decrease in spermatocyte production, corrugation of sperm cell nuclear envelopes and distention of the endoplasmic reticulum of elongate spermatids. It is concluded that furazolidone depresses pituitary LH output but may, in addition, directly affect spermatogenesis and sperm motility.  相似文献   
69.
This work examines the effect on the weights of vital body organs, on blood biochemical variables, on neuromuscular coordination and on cerebral microcirculation of aqueous extracts of Teucrium stocksianum, given to mice in drinking water at concentrations of 2 and 4% for 56 days. The treatment caused progressive impairment of neuromuscular coordination, as evidenced by the time spent on the rota-rod. After photochemical challenge, the time for first observable platelet aggregation in arterioles was shorter than for the control group by 22 and 45% in the 2 and 4% T. stocksianum-treated groups, respectively. Platelet aggregation on the venular side was not affected by the treatment nor were microvascular diameters. Treatment with the plant extract produced no statistically significant effect on the plasma biochemical variables that are considered indices of liver and kidney function. Histologically, brains obtained from mice treated with T. stocksianum showed loss of cerebellar Purkinje cells. Although it is likely that the accelerated platelet aggregation might have contributed to an ischaemic effect which could, at least in part, have caused the cytotoxicological changes, this does not exclude the possibility of a direct cytotoxicological effect of the plant extract. Further pharmacological and toxicological investigations on Teucrium species seem warranted.  相似文献   
70.
The most important complications from tonsillectomy and adenoidectomy are bleeding, stridor, and laryngospasm. This controlled, double-blind study was designed to investigate the effects of topical and intravenous lidocaine on stridor and laryngospasm. A total of 134 patients scheduled for elective tonsillectomy and/or adenoidectomy were randomly separated into four groups. In the topical lidocaine group 4 mg/kg of 2% lidocaine was applied to subglottic, glottic, and supraglottic areas before endotracheal intubation. Normal saline solution was used topically for the first control group. In the intravenous lidocaine group, patients were given 1 mg/kg of 2% lidocaine before extubation, and the same amount of 0.9% NaCl was given to the second control group. Postoperative stridor, laryngospasm, cyanosis, bleeding, sedation degree, and respiratory depression were observed, and plasma lidocaine levels were measured. Both topical and intravenous lidocaine groups revealed less stridor and laryngospasm than the control groups, and no difference was found between the topical and intravenous lidocaine groups except the higher sedation scores in the early postoperative period for the intravenous lidocaine group. (Otolaryngol Head Neck Surg 1998;118:880-2.)  相似文献   
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