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Intracranial aneurysms are common extrarenal manifestations of autosomal dominant polycystic kidney disease (ADPKD). Although their natural history is not completely understood, small asymptomatic intracranial aneurysms in patients with ADPKD often are not treated but are followed with serial magnetic resonance (MR) angiography. The authors report the unique case of a patient with ADPKD who bled from a previously documented asymptomatic 3-mm intracranial aneurysm. This 42-year-old man with ADPKD suffered a subarachnoid hemorrhage (SAH) from a 7-mm left pericallosal artery aneurysm. This aneurysm was clipped and the patient made an excellent recovery. An irregular asymptomatic 3-mm right middle cerebral artery (MCA) aneurysm had also been demonstrated on angiography. While the patient was considering elective surgery for the MCA aneurysm, he suffered a hemorrhage from this lesion 10 weeks after the initial SAH. The aneurysm was clipped and the patient made a satisfactory recovery (he was moderately disabled). In this report the authors indicate that small asymptomatic intracranial aneurysms are not always innocuous in patients with ADPKD, and they suggest that treatment should be strongly considered for these lesions in this group of patients when there is a history of SAH or the aneurysm is irregular in appearance. Because MR angiography studies may not adequately define the configuration of small aneurysms and irregularity may easily be missed, conventional angiography is recommended for patients with ADPKD who are found to have an intracranial aneurysm on screening with MR angiography. 相似文献
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WF Grashoff JK Sont PJ Sterk PS Hiemstra WI de Boer J Stolk J Han JM van Krieken 《Canadian Metallurgical Quarterly》1997,151(6):1785-1790
Chronic obstructive pulmonary disease (COPD) is considered to be caused in part by smoking-induced inflammation, but it is unknown which inflammatory cells within the small airways are associated with the obstruction. We investigated the inflammatory infiltrate in the small airways of 16 current or ex-smokers with COPD (FEV1 < or = 75% predicted) and 15 without COPD (FEV1 > or = 85% predicted) in pneumectomy specimens that were removed for lung cancer. Mast cells, macrophages, neutrophils, eosinophils, T cells, and B cells were identified using immunohistochemistry on formalin-fixed, paraffin-embedded specimens. These cells were quantified in the epithelium and the remainder of the airway wall. The number of mast cells and macrophages in the epithelium, but not in the remainder of the airway wall, was significantly increased in patients with COPD. Neutrophil and T cell numbers did not differ between the groups. Only few B cells and eosinophils were present in both groups. Smoking history, perioperative steroid usage, tumor localization, or reversibility in the FEV1 to salbutamol could not account for the observed differences. We conclude that the number of epithelial mast cells and macrophages is increased in the bronchioli in smokers with airflow limitation, suggesting a role in development of COPD. 相似文献
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Three cases of metastatic basal-cell carcinoma are reported. All of the cases were relatively small when compared with other lesions reported in the literature. With early chemosurgical treatment of small recurrent carcinomas, metastasizing basal-cell carcinoma will be a condition of the past. 相似文献
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PJ Trotter WI Wu J Pedretti R Yates DR Voelker 《Canadian Metallurgical Quarterly》1998,273(21):13189-13196
In an effort to understand molecular mechanisms of intracellular lipid transport, we have focused upon specific events required for de novo aminophospholipid synthesis in the yeast Saccharomyces cerevisiae. A genetic system for examining the steps between phosphatidylserine (PtdSer) synthesis in the endoplasmic reticulum and its transport to and decarboxylation by PtdSer decarboxylase 2 in the Golgi/vacuole has been developed. We have isolated a mutant, denoted pstB1, that accumulates PtdSer and has diminished phosphatidylethanolamine formation despite normal PtdSer decarboxylase 2 activity. The lesion in PtdSer metabolism is consistent with a defect in interorganelle lipid transport. A genomic DNA clone that complements the mutation was isolated, and sequencing revealed that the clone contains the STT4 gene, encoding a phosphatidylinositol 4-kinase. The pstB1 mutant exhibits a defect in Stt4p-type phosphatidylinositol 4-kinase activity, and direct gene replacement indicates that STT4 is the defective gene in the mutant. Creation of an STT4 null allele (stt4Delta::HIS3) demonstrates the gene is essential. These results provide evidence that implicates phosphoinositides in the regulation of intracellular aminophospholipid transport. 相似文献
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To find the feasibility of treatment for congenital bile duct atresia, we studied the usefullness of extracorporeal hemoperfusion over activated charcoal in canine obstructive jaundice. One, three and five weeks after ligation and disection of common bile duct in 5 dogs we performed the hemoperfusion over activated charcoal extracorporeally (group 3). In this animals we examined hematological and blood coagulation studies, serum electrolyte levels, kidney function tests and liver chemistries. As control in 5 animals we carried out after sham operation the perfusion without common bile duct ligation (group 2) and in 5 animals only common bile duct ligation without perfusion (group 1). In the liver chemistries we found 2 weeks after 2nd and 3rd perfusion (5 and 7 weeks after bile duct ligation) lower levels of serum bilirubin, GOT, GPT and SDH in treated group than in non-treated jaundiced animals. It suggest the effectiveness of hemoperfusion with activated charcoal in the treatment of occlusive jaundice. There were no alteration in the hematological studies, serum electrolyte levels and kidney function tests. PT and PTT was prolonged in the jaundiced animals there were no significant differences with and without hemoperfusion. 相似文献
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An analysis of the theoretical behavior of a proposed zero-order drug delivery system is presented. Equations describing drug release with time are developed using a physically realistic model. The theory agrees well with experimental data and indicates that drug release from the device is nearly, although not rigorously, zero order. 相似文献
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