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11.
We report our experience of renal transplantation in three patients treated for Wilms' tumor (with lung metastasis in two of them), and review 26 previously reported cases in order to define the current indications of transplantation in this setting. Our patients, aged 5-12 years, were transplanted 13-95 months after completion of Wilms' tumor treatment. All three are alive and tumor-free, two with a functioning graft 20 and 97 months after transplantation. Two findings emerge from the review of the literature. First, posttransplant mortality is influenced by the delay between completion of tumor treatment and transplantation. Mortality reaches 79% when that delay is less than one year but falls to 27% when that delay exceeds one year. Second, the prognostic value of pretransplant metastasis depends on its location. All four patients with pretransplant abdominal metastasis died with active metastatic disease. By contrast, of three patients treated before transplantation for metastasis confined to the lung, two are alive and tumor free. We conclude that renal transplantation should be offered to patients successfully treated for Wilms' tumor for at least one year, even if the disease has been complicated by pulmonary metastasis. Several long-term survivors attest that the disease can be cured even under maintenance immunosuppression.  相似文献   
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Ischemic stroke occurs in 0.2-0.4% of patients undergoing left heart catheterization, and is responsible for 5-10% of the mortality associated with the procedure. The main predisposing factors for this complication are female gender, complex atherosclerotic plaques in the ascending aorta, and peripheral arterial disease. The possibility of timely intervention with reperfusion therapy supports close clinical monitoring during the immediate post-catheterization period. The cardiologist should be familiar with the various types of stroke reperfusion therapy and its indications according to the time interval between catheterization and the stroke. The decision should be discussed with neurology and neuroradiology.  相似文献   
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Summary The effectiveness of calcium antagonists on a chronic cerebral vasospasm after an SAH is still under debate. Calcium channel blockers such as nimodipine, nefedipine etc. can dilate spastic arteries by intrathecal administration, but not by systemic (iv or po) use. HA 1077 is a novel and potent calcium antagonist vasodilator which is considered to act by employing different mechanisms from the usual calcium channel blockers since it inhibits 1. calcium ionophore A 23187 induced contraction in arterial strips and 2. phenylephrine induced contraction in calcium free media, suggesting that its site of action is in the intracellular space. HA 1077 is water soluble and relatively stable in light.In the present study, the efficacy of HA 1077 was evaluated on dogs by using the spiral arterial strips in vitro and by angiography in vivo. In the arterial strips from the control dogs, a 50% relaxation of KCl (15 mM) induced contraction was obtained by a 10–6 M HA 1077 for the intracranial basilar and middle cerebral arteries, while a 10–5 M was needed to obtain the same effect for the extracranial common carotid and vertebral arteries, indicating that HA 1077 is more effective for the intracranial arteries. A vasospasm was produced by the two haemorrhage model of Varsoset al. The average angiographic diameter of the basilar artery was reduced to 60% of the control on SAH day 7. Intravenous infusion of HA 1077 (0.5–3 mg/kg/30 min) significantly dilated the spastic basilar artery (up to 20–30%), for over 2 hours. A fall in the systemic BP remained less than 20% during this time. Such spasmolytic effects by intravenous administration could not have been obtained with the usual calcium channel blockers. HA 1077 may be suitable for the treatment of a vasospasm in humans as well.  相似文献   
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PROBLEM: Pregnancy affects the maternal immune system and the clinical course of maternal diseases. Here we report the changes in the detailed lymphocyte subsets of helper T cells, suppressor T cells, CD5+ B cells, T cell receptor (TCR) αβ-positive T cells (Tαβ cells), TCRαβ-negative T cell (Tγδ cells), and others during and after pregnancy through to one year postpartum, and discuss the significance of the changes. METHOD: The absolute numbers of helper T cells, suppressor T cells, cytotoxic T cells, TCRαβ-negative T cells (Tγδ cells), CD5 B cells, CD5+ B cells, and NK cell subsets were examined by two-color flow cytometry in peripheral blood from 51 healthy non-pregnant women, 106 healthy pregnant women, and 148 healthy postpartum women. RESULTS: In early pregnancy, the numbers of suppressor T cells and NK cells with strong cytotoxicity (NK+++ cells) increased, and the number of cytotoxic T cells decreased. In late pregnancy, the helper T cell and NK+++ cell numbers decreased. Tαβ, CD5 B and CD5+ B cells decreased during pregnancy. After delivery, helper T cells and cytotoxic T cells increased from 1 to 4 months postpartum, and suppressor T cells increased at 7 months postpartum. TCRαβ-negative T cells increased at 4 to 10 months postpartum. Both CD5 and CD5+ B cells decreased further at 1 month postpartum, but CD5+ B cells increased markedly at 7 to 10 months postpartum. CONCLUSIONS: These data indicate that 1) early increases of suppressor T cells and NK+++ cells during pregnancy may be related to the mechanism to accept or reject the fetus in early pregnancy, respectively; 2) late decreases of helper T cells and NK+++ cells may be related to the maintenance of pregnancy: 3) postpartum increases of helper T cells, cytotoxic T cells, TCRαβ-negative T cells (Tγδ cells), and CD5+ B cells may be related to the postpartum aggravation of autoimmune diseases; and 4) the immunological effects of pregnancy remains until about 1 year after delivery.  相似文献   
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Effects of the 1-methyl-4-phenylpyridinium ion (MPP+) on DOPA formation and phosphorylation of tyrosine hydroxylase (TH) of rat pheochromocytoma PC12h cells were examined after the cells were cultured with MPP+. DOPA formed from endogenous tyrosine in PC12h cells after a 3-day culture with 100 microM MPP+ was decreased to less than 50% as compared to that in the control cells cultured without MPP+. Kinetical study showed that two apparent forms of TH with different Km existed in the cells cultured with 100 microM MPP+ but one form in that of control. Incorporation of radioactive phosphate into TH molecule was also reduced to 50% of its control value following a 3-day exposure to 100 microM MPP+. These results suggest that MPP+ acutely inhibits the phosphorylation of TH to decrease cellular DOPA formation.  相似文献   
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Sitosterolaemia (also known as phytosterolaemia, MIM 210250) is a rare recessive autosomal inherited disorder, characterised by the presence of tendon and tuberous xanthomas, accelerated atherosclerosis and premature coronary artery disease. The defective gene is hypothesised to play an important role in regulating dietary sterol absorption and biliary secretion, thus defining a molecular mechanism whereby this physiological process is carried out. The disease locus was localised previously to chromosome 2p21, in a 15 cM interval between microsatellite markers D2S1788 and D2S1352 (based upon 10 families, maximum lodscore 4.49). In this study, we have extended these studies to include 30 families assembled from around the world. A maximum multipoint lodscore of 11.49 was obtained for marker D2S2998. Homozygosity and haplotype sharing was identified in probands from non-consanguineous marriages from a number of families, strongly supporting the existence of a founder effect among various populations. Additionally, based upon both genealogies, as well as genotyping, two Amish/Mennonite families, that were previously thought not to be related, appear to indicate a founder effect in this population as well. Using both homozygosity mapping, as well as informative recombination events, the sitosterolaemia gene is located at a region defined by markers D2S2294 and Afm210xe9, a distance of less than 2 cM.  相似文献   
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