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41.
Extracranial paranasal spread of meningiomas is uncommon. We describe the management of four cases, all of which first presented to an oto-rhino-laryngologist for an opinion. We suggest that greater use of modern imaging techniques could lead to earlier diagnosis. The natural history of extracranial spread is relatively benign but the management of regrowth of residual disease is difficult. We therefore suggest radical surgery in the first instance provided that the patients general health and configuration of the tumour allow.  相似文献   
42.
Occult congenital temporal lobe encephalocele has rarely been reported in association with medically intractable complex partial seizures. The four previously reported cases were unsuspected preoperatively. We present the case of an 18-year-old woman with intractable complex partial seizures since age 13. Seizure onset was electrically localized to the right temporal lobe. Preoperative neuroimaging studies revealed a middle fossa defect and inferior herniation of the right temporal lobe. Pathologic examination of the resected encephalocele revealed prominent features of meningoangiomatosis. We believe this to be the first case of temporal lobe encephalocele and epilepsy to be diagnosed preoperatively, and the first case also to be associated with meningoangiomatosis. The relevant literature on meningoangiomatosis and on temporal lobe encephalocele as a cause of epilepsy is reviewed.  相似文献   
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Body art in the form of tattoos and piercing has become increasingly popular amongst children and teenagers, and is nowadays more socially acceptable despite media reports citing tissue destruction and death. Our study explored the awareness and experience of patients with congenital heart disease, and of cardiologists and professionals responsible for their care.  相似文献   
45.
Patients with sickle cell anemia have considerably less hypertension than the black population in general. Factor(s) offering "protection" from hypertension in these patients remain unknown. Hormonal and hemodynamic parameters involved in blood pressure regulation were evaluated in normotensive, stable sickle cell patients and black nonsickle normotensive controls. There was no difference in systolic, diastolic, or mean arterial blood pressure between the two groups. The characteristic hemodynamic findings of increased cardiac index, renal plasma flow, and plasma volume were observed in the sickle cell patients. Urinary sodium excretion was comparable on an ad libitum, high sodium, and low sodium diet. In contrast, plasma renin activity was greater in sickle cell patients at all levels of sodium intake in both supine and upright positions. These findings suggested possible altered vascular responsiveness to endogenous angiotensin II. Plethysmography revealed that sickle cell patients had greater forearm blood flow than normal controls and black nonsickle chronic anemic controls at rest, during cold stimulation, and during exercise. Forearm vascular resistance was significantly lower in the patients and did not increase with cold-induced, sympathetic-mediated stimulation. To assess these findings more directly, the pressor response to the exogenous administration of graded doses of angiotensin II and norepinephrine was measured. There was a marked decrease in the pressor response to angiotensin II but not to norepinephrine in the sickle cell patients. The findings in these studies indicate fundamental differences in blood pressure control in the sickle cell patient, probably at the vascular level.  相似文献   
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Cytopathic effect of in situ gene therapy in prostate cancer   总被引:3,自引:0,他引:3  
This is a morphologic study of in situ gene therapy effects in patients with prostate cancer using the Herpes Simplex VirusThymidine Kinase gene (HSV-tk) followed by ganciclovir. Prostatectomy specimens from the first 4 patients showed the following morphologic changes: (1) various degrees of necrosis were seen in cancer foci; (2) cytopathic changes were seen across the whole spectrum of Gleason grades; (3) the normal prostate was rarely affected by necrosis, but contained an intense mononuclear infiltrate; (4) loss of nuclear detail was a common finding. Volumetric studies showed that only portions of the tumor show morphologic effects as well as an inverse relationship between percentage of affected tumor and prostate and tumor size. An inflammatory response was observed, with predominance of CD20-positive cells in normal prostate tissue, CD8 (cytotoxic T cells) in the tumor, and macrophages in all areas of the treated prostates. We believe that these changes represent the cytopathic effect of our in situ gene therapy on prostate cancer, and that they trigger a local immune response.  相似文献   
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BACKGROUND. Serum carcinoembryonic antigen level is raised in 80% of patients undergoing colonic resection for cancer. Subsequent elevation in the follow-up period may precede signs and symptoms as an indicator of recurrent disease. there is little evidence that "classical" follow up of patients in the general surgical outpatient clinic improves either survival or quality of life. Regular carcinoembryonic antigen level estimation requested by the general practitioner, allied to day-case colonoscopic surveillance may be a more rational approach. AIM. A study was undertaken to investigate the relationship between raised carcinoembryonic antigen level and the recurrence of colorectal cancer in patients following a curative primary resection. METHOD. Retrospective analysis was carried out on the notes of 125 patients who had attended a dedicated hospital colorectal follow-up clinic between 1988 and 1992. Carcinoembryonic antigen level data were obtained by subsequent examination of the University of Edinburgh Department of Clinical Chemistry (immunoassay section) carcinoembryonic antigen database. RESULTS. A single carcinoembryonic level result of more than 100 ul-1 (normal range less than 60 ul-1) was found to be a highly sensitive (87%), specific (89%), and accurate (88%) indicator of recurrent disease. Raised carcinoembryonic antigen level preceded symptoms in 72% of patients with recurrence of colorectal cancer. CONCLUSION. Sequential laboratory estimation of carcinoembryonic antigen level organized by the general practitioner may represent an accurate method of detecting recurrent colorectal disease. Hospital review could be limited to colonoscopic surveillance and restaging of patients referred with evidence of recurrent disease.  相似文献   
50.
Apical membrane antigen 1 (AMA1) is regarded as a leading malaria blood-stage vaccine candidate. While the overall structure of AMA1 is conserved in Plasmodium spp., numerous AMA1 allelic variants of P. falciparum have been described. The effect of AMA1 allelic diversity on the ability of a recombinant AMA1 vaccine to protect against human infection by different P. falciparum strains is unknown. We characterize two allelic forms of AMA1 that were both produced in Pichia pastoris at a sufficient economy of scale to be usable for clinical vaccine studies. Both proteins were used to immunize rabbits, singly and in combination, in order to evaluate their immunogenicity and the ability of elicited antibodies to block the growth of different P. falciparum clones. Both antigens, when used alone, elicited high homologous anti-AMA1 titers, with reduced strain cross-reactivity. Similarly, sera from rabbits immunized with a single antigen were capable of blocking the growth of homologous parasite strains at levels theoretically sufficient to clear parasite infections. However, heterologous inhibition was significantly reduced, providing experimental evidence that AMA1 allelic diversity is a result of immune pressure. Encouragingly, rabbits immunized with a combination of both antigens exhibited titers and levels of parasite inhibition as good as those of the single-antigen-immunized rabbits for each of the homologous parasite lines, and consequently exhibited a broadening of allelic diversity coverage.  相似文献   
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