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51.
An analysis of the presently available data shows that the principal pineal hormone melatonin is capable of influencing, both directly and indirectly, the state of the immune system. The immunotropic activity of this hormone can account for the stress-protective, antitumor, and antiviral effects of melatonin.  相似文献   
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INTRODUCTION: Heterotaxy syndrome (Ivemark syndrome, or asplenia-polysplenia syndrome) is a heterogeneous group of disease with disturbed body symmetry and malposition of internal organs. Heterotaxy syndrome is caused by the disturbance of the left/right axis in the early embryonic period. AIM OF THE STUDY: The most frequency of heterotaxy syndrome's concomitant anomalies during a five year period in own fetopathology material. MATERIALS AND METHODS: Data of fetopathologic examination of 13 fetuses suffering from prenatally diagnosed heterotaxy syndrome. RESULTS: Situs ambiguus was detected in 9 cases out of 13. In the remaining 4 cases situs inversus totalis was diagnosed. The most frequent and important associated malformation included congenital heart disease was AV channel (10/13) and great vessel anomaly (10/13). CONCLUSION: In cases with prenatally detected complex cardiac anomalies (especially AV channel cases) heterotaxy anomaly must be taken into consideration, with main consequences in prenatal counselling.  相似文献   
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Both chromophobe carcinoma and sarcomatoid carcinoma of the kidney are rare. The former is characterized by a relatively good prognosis, while the latter is a highly aggressive tumor. Coexistence of the two components in one renal tumor, which has been reported only rarely, is therefore paradoxical. Both sarcomatoid and chromophobe renal carcinoma were diagnosed in a 52-year-old woman following nephrectomy and resection of metastases in the right lobe of the liver. She died of the disease two months after the first operation; only the sarcomatoid component of her tumor was seen in the liver metastasis and the recurrent carcinoma. Differences in phenotype, immunophenotype and DNA-ploidy patterns of the two components are reported. The intensive p53 staining observed only in the sarcomatoid area supports the role of the TP53 gene in the transformation of chromophobe renal carcinoma to sarcomatoid carcinoma.  相似文献   
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Metastatic cardiac myxoma   总被引:5,自引:0,他引:5  
A 22-year-old woman who had a history of three cardiac operations and a bilateral femoral embolectomy for recurrent cardiac myxoma and myxoma embolism, respectively, was accepted to our clinic with multiple immobile peripheral masses. One of them was compressing the left common femoral artery. This mass was extirpated. Pathology examination revealed myxoma. Chemotherapy was given to the patient and regression of the masses was observed.  相似文献   
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Atrial myocytes synthesise atrial natriuretic factor prohormone consisting of 126 amino acids (ANP1-126) which is subsequently processed to several fragments. Atrial natriuretic factor (ANF, ANP99-126) originating from the C-terminal portion of prohormone is a best described atrial peptide. However, several peptides originating from the N-terminus of this precursor also circulate and produce significant diuresis, natriuresis and vasodilatation. These are: long acting natriuretic peptide (ANP1-30), vessel dilator (ANP31-67) and kaliuretic peptide (ANP79-98). ANP1-98 and ANP68-98 also circulate. Kaliuretic peptide specifically stimulates urinary potassium excretion. These peptides are slowly metabolised and their plasma concentration is higher than ANF suggesting their important role in water-electrolyte homeostasis and regulation of vascular tone. N-terminal atrial peptides don't bind to classical natriuretic peptide receptors, each of them has probably its own unique receptors. Although these peptides activate particulate guanylate cyclase in a number of tissues, some of their effects, for example natriuresis, are not mediated by cGMP but rather by prostaglandin E2. Plasma concentration of N-terminal atrial peptides may be useful in diagnosis and risk stratification in patients with heart failure and after myocardial infarction. Recently N-terminal fragment of brain natriuretic peptide (BNP1-76) was identified in the blood. This peptide is secreted together with its C-terminal partner, BNP77-108 by ventricular myocytes. Some studies suggest that N-terminal BNP may be also a useful diagnostic tool in cardiovascular diseases.  相似文献   
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Diazepam (0.5 mg/kg) decreases the swimming-stress-induced activation of the pyramidal neurons in the dorsal hippocamp. This is manifested by a decrease in the stress-induced glycogen consumption, an increase in the RNA content, and (less pronounced) increased in the nucleocytoplasmic ratio.  相似文献   
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A case of gastroschisis complicated by vanishing bowel and presenting as jejunal atresia is reported that is uniquely different from previously reported cases. Following delivery, complete closure of the abdominal wall with a small fascial defect was observed. Complete healing of this fascial defect was observed at 1 month of age. Accepted: 5 January 1999  相似文献   
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