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91.
Amiodarone is extensively used in cardiology practice because of its excellent antiarrhythmic properties. It produces alterations in thyroid functional because it contains 37% iodine and it is structurally similar to the thyroid hormones. Amiodarone inhibits 5'-deiodinase in the liver. The incidence of amiodarone-induced hyperthyroidism is between 6% and 12% of treated patients. The figures for pediatric patients are similar. Determination of tri-iodothyronine (T3), thyroxine (T4) and thyroid-stimulating hormone (TSH) plays an important role in the diagnosis and follow-up of thyroid alterations. Treatment options in amiodarone-induced hyperthyroidism in children include thionamide, potassium perchlorate, and prednisone. We present the case of hyperthyroidism secondary to amiodarone in a 10-year-old boy with Marfan's syndrome who was admitted several times for crises of paroxysmal supraventricular tachycardia and atrial fibrillation. After amiodarone treatment he presented a clinical and analytical picture of hyperthyroidism with very low TSH levels and increased free-T4 levels. Thyroid echography and scintigraphy were normal. Treatment with thiamazole did not alter the clinical picture, which returned to normal after prednisone administration. Currently, prednisone is being slowly withdrawn.Amiodarone. Hyperthyroidism. Antiarrhythmics.  相似文献   
92.
93.
Ten haemophilia centres in northern Europe have pooled data on 202 haemophilic children who were infected with HIV between 1979 and 1986. All cases were under 16 years of age on 1 July 1985. The age at infection ranged from 1-15 years. Thirty seven cases (18%) had progressed to AIDS by 1 July 1991 and 15 of these have died. Persistent generalised lymphadenopathy has been noted in 102 patients of whom 18 (17%) have developed AIDS. Twenty three of the remaining patients (23%) have not. CD4+ T cell counts have fallen steadily. Of 36 patients who have had shingles since seroconversion, 19 (53%) had counts below 0.2 x 10(9)/l. Thirty five out of 145 patients without shingles (24%) had similar values. The mean IgA concentration in patients with CD4+ T cell counts above 0.5 x 10(9)/l was 2.38 g/l, between 0.2 and 0.5 was 3.07 g/l, and in those with CD4+ T cell counts below 0.2 x 10(9)/l the mean IgA concentration was 4.58 g/l. Treatment patterns have altered between 1989 and 1991, with increased use of zidovudine in patients without AIDS and a marked increase in primary prophylaxis against pneumocystis pneumonia. This has been associated with a decline in the incidence of pneumocystis as an indicator disease in new AIDS cases from 56% in 1989 to 20% in 1991. These observations indicate that persistent generalised lymphadenopathy does not worsen the outlook, but shingles does. Rising IgA concentrations are markers for disease progression. Modern prophylactic regimens are delaying the onset of indicator disease, but CD4 values continue to fall steadily.  相似文献   
94.
BACKGROUND: It has been proven that cytokeratins (CKs) are useful tumor markers for the follow-up, treatment monitoring and prognosis evaluation of lung cancer and among these, tissue polypeptide antigen (TPA) plays an important role. Nevertheless, only a small number of studies have been reported about their diagnostic capacity. Bronchoalveolar lavage (BAL) can be divided into two fractions: bronchiolar (BF) and alveolar (AF). For the above reasons, our aims were (1) to analyze the diagnostic usefulness of TPA in the BAL of lung cancer patients and (2) to observe if, in lung cancer patients, TPA levels in the two BAL fractions are different. This should mean that the study of tumor markers in the BAL should be carried out in both fractions to increase their diagnostic capacity. METHODS: We studied 289 BALs divided into two phases. In phase I, TPA was analyzed in the BAL of six groups of subjects (healthy persons, chronic bronchitis, asthma, respiratory infections, diffuse interstitial pulmonary diseases and lung cancer). In phase II, TPA was studied in both BAL fractions of a group of patients with lung cancer. RESULTS: We observed that TPA levels were significantly higher in the BAL of patients with bronchogenic neoplasias. In these patients, TPA was increased in the BF of the lavage in relation to the AF. In smoker patients with pulmonary carcinomas, TPA was higher in the AF of the BAL than in the lavage of non-smokers. This did not occur in the BF. We found no relation between the TPA concentrations and cancer histology. CONCLUSIONS: We believe that TPA is a useful tumor marker with diagnostic capacity and this capacity is increased when it is studied in the two BAL fractions. Smoking habit may play a role in the secretion of tumor markers by the tumor cells.  相似文献   
95.
The present study investigated the effect on water and food intake in the rat of the intracerebroventricular (ICV) injection of neuropeptide K (NPK), the N-terminally extended form of neurokinin A. NPK inhibited water deprivation-induced water intake even at 31.2 ng/rat. At higher doses, it inhibited also water intake induced by ICV angiotensin II or by subcutaneous hypertonic NaCl, and food-associated drinking, the threshold dose being 125 ng/rat. In response to 125 ng/rat, food intake following 16 h food deprivation was not reduced. NPK inhibited food intake only at 500 ng/rat, a dose that evoked excessive grooming in treated animals. Thus NPK is a potent inhibitor of water deprivation-induced drinking and at higher doses it exerts a general antidipsogenic effect towards several dipsogenic determinants, without affecting food intake. On the other hand, it inhibits food intake only at high doses, 500 ng/rat or more, but this inhibition might be just related to the intense grooming evoked. The effects of NPK on ingestive behavior are markedly different from those of neurokinin A, which selectively inhibits osmotic drinking and food-associated drinking. These differences suggest that NPK itself may exert its effects on the central nervous system, not necessarily through the conversion to neurokinin A.  相似文献   
96.
Survey of reproductive health among female MR workers   总被引:6,自引:1,他引:5  
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97.
A retrospective study was made of the results of high dose radiotherapy (≥50 Gy) given to 171 patients with inoperable, intrathoracic non small cell lung cancer from January 1971–April 1973. Local control was dependent on the total tumor dose: after one year local control was 63% for patients treated with >65 Gy, the two year local control was 35%. If treated with <65 Gy the one year local control was ≤40%. Tumor doses correlated with the size of the booster field. If the size of the booster field was <100 cm2, the one year local control was 72%; the two year local control was 44%. Local control was also influenced by the performance status, by the localization of the primary tumor in the left upper lobe and in the periphery of the lung. Local control for tumors in the left upper lobe and in the periphery of the lung was about 70% after one year, and about 40% after two years. The one and two years survival results were correlated with the factors influencing local control. The dose factor, the localization factors and the performance influenced local control independently. Tumors localized in the left upper lobe did metastasize less than tumors in the lower lobe, or in a combination of the two. This was not true for the right upper lobe. No correlation between the TNM system, pathology and the prognosis were found.  相似文献   
98.
1. The South American amphibian Leptodactylus pentadactylus labyrinthicus and the South African amphibian Xenopus laevis contain in their skin a polypeptide indistinguishable from caerulein prepared from the Australian amphibian Hyla caerulea.2. The caerulein content of different batches of Leptodactylus pentadactylus labyrinthicus skins varies from 10 to 500-600 mug/g tissue. Drying of the skin causes either a moderate decrease or a slight increase in the caerulein content. Methanol extraction gives considerably higher yields of caerulein than acetone extraction.3. Caerulein or caerulein-like polypeptides also occur in the skin of several other species of Leptodactylus together with 5-hydroxyindole alkylamines and imidazole alkylamines. Yet other species of Leptodactylus lack caerulein-like polypeptides and 5-hydroxyindole alkylamines.4. It is suggested that caerulein and caerulein-like polypeptides may have some function either in the regulation of secretory processes of the skin or in the exchange of water and electrolytes through the skin, or in both.  相似文献   
99.
A study has been made, under transient conditions, of the uptake of 125I albumin by the endothelial surface of isolated dog carotid arteries. Effective rate constants were determined and the apparent activation energy was calculated to be about 13 kcal/mol in the range 25-37 degrees C. Label uptake was not significantly altered by the presence of 1 mmol/1 potassium cyanide or 10 mmol/1 iodoacetate in the incubating medium, or by the absence of substrate from it, consistent with the process being primarily passive. It appeared that the label entered the wall mainly by other routes than the endothelial inter-cell clefts.  相似文献   
100.
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