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21.
Perforation of the inferior vena cava with aortic and vertebral penetration by a suprarenal Greenfield filter 总被引:1,自引:0,他引:1
Various complications have been reported after insertion of the Greenfield filter. This report describes an unusual complication after suprarenal placement of this filter: spreading of the filter struts, with perforation of the inferior vena cava, and penetration of the aorta and a vertebral body, followed by fracture of one of the struts. 相似文献
22.
In this case, a male patient presented with a clinically and radiographieally unstable slipped capital femoral epiphysis (SCFE) as well as slipped calcaneal epiphysis years. Subsequent thorough at the age of 23 work-up revealed that he had some features of rickets and labo- ratory test demonstrated he had hypophos- phatemia (2.3mg/dl), normocalcemia, normal vi- tamin D metabolite levels, and secondary hy- perparathyroidism. 相似文献
23.
24.
White-matter lesions in MR imaging of clinically healthy brains of elderly subjects: possible pathologic basis 总被引:9,自引:0,他引:9
Patchy white-matter lesions occur in the magnetic resonance (MR) imaging brain studies of 20%-30% of neurologically healthy elderly subjects. To determine the frequency of histologically verifiable white-matter lesions at autopsy in such subjects the authors examined serial, microscopic, whole brain sections from 15 clinically healthy subjects aged 52-72 years. Small white-matter lesions were found in 12. In these 12, zones of atrophic perivascular demyelination were present in eight brains. These are not the familiar thrombotic, embolic, or ischemic vascular lesions that produce acute necrosis. This mild vascular insufficiency produces atrophy, which has been recognized in the pathology literature but whose clinical significance remains unknown. Other lesions seen were small vascular malformations in the centrum ovale in four brains, diverticula of the lateral ventricle extending into the white matter in three, and an isolated central white-matter infarction in one. All of these lesions are probably the basis of the patchy white-matter lesions seen on MR imaging studies in the neurologically healthy elderly population. 相似文献
25.
Nitric oxide (NO) is a paramagnetic gas that has been implicated in a wide range of biologic functions. The common pathway to evoke the functional response frequently involves the formation of an iron- nitrosyl complex in a target (heme) protein. In this study, we report on the interactions between NO and cobalt-containing vitamin B12 derivatives. Absorption spectroscopy showed that of the four Co(III) derivatives (cyanocobalamin [CN-Cbl], aquocobalamin [H2O-Cbl], adenosylcobalamin [Ado-Cbl], and methylcobalamin [MeCbl]), only the H2O- Cbl combined with NO. In addition, electron paramagnetic resonance spectroscopy of H2O-Cbl preparations showed the presence of a small amount of Cob-(II)alamin that was capable of combining with NO. The Co(III)-NO complex was very stable, but could transfer its NO moiety to hemoglobin (Hb). The transfer was accompanied by a reduction of the Co(III) to Co(II), indicating that NO+ (nitrosonium) was the leaving group. In accordance with this, the NO did not combine with the Hb Fe(II)-heme, but most likely with the Hb cysteine-thiolate. Similarly, the Co(III)-NO complex was capable of transferring its NO to glutathione. Ado-Cbl and Me-Cbl were susceptible to photolysis, but CN- Cbl and H2O-Cbl were not. The homolytic cleavage of the Co(III)-Ado or Co(III)-Me bond resulted in the reduction of the metal. When photolysis was performed in the presence of NO, formation of NO-Co(II) was observed. Co(II)-nitrosyl oxidized slowly to form Co(III)-nitrosyl. The capability of aquocobalamin to combine with NO had functional consequences. We found that nitrosylcobalamin had diminished ability to serve as a cofactor for the enzyme methionine synthase, and that aquocobalamin could quench NO-mediated inhibition of cell proliferation. Our in vitro studies therefore suggest that interactions between NO and cobalamins may have important consequences in vivo. 相似文献
26.
Sickle cell anemia patients have low erythropoietin levels for their degree of anemia 总被引:2,自引:1,他引:2
We have studied serum immunoreactive erythropoietin (SIE) levels in 28 patients with sickle cell anemia (SCA) without renal insufficiency and in 17 patients with nonhemoglobinopathy anemias of comparable severity using a sensitive radioimmunoassay procedure. An exponential relationship between SIE level and degree of anemia was noted in all patients. However, in nonhemoglobinopathy anemia, a sharp rise in the SIE level occurred as hemoglobin (Hb) levels fell below about 12 g/dL, whereas in sickle cell patients the increase was not marked until hemoglobin fell to about 9 g/dL. The response was more blunted in older SCA patients than in younger ones. A linear regression model relating SIE level to Hb level, presence/absence of SCA, and age explained 63% of the variation in SIE. We conclude that the serum erythropoietin levels in SCA increased at a lower hemoglobin concentration and are of a lower magnitude than that of the other anemias. 相似文献
27.
M McCarthy JB Yuan A Campbell NP Lenzo K Butler‐Henderson 《Journal of Medical Imaging and Radiation Oncology》2008,52(6):564-569
18F‐fluorodeoxyglucose positron emission tomography (FDG‐PET) scans in the first 49 patients referred with either possible brain tumour or brain tumour recurrence were reviewed. FDG‐PET imaging was reported with reference to anatomical imaging. Based on the report the FDG study was classified as either positive or negative for the presence of tumour. Thirty‐eight cases were included in the analysis, 21 having pathological data and 17 with diagnostic clinical follow up. Eleven were excluded, as they had inadequate follow‐up data. Of the 21 cases with pathology, 18 were shown to have tumour. In this group there were five false‐negative scans and two false‐positive PET scans. Seventeen cases were assessed by clinical follow up, nine were considered to have been tumour. There were two false negatives with one false positive. The overall sensitivity, specificity and positive and negative predictive values were 74, 73, 87 and 53% respectively. This is similar to figures previously quoted in published work. Despite relatively limited numbers, the utility of FDG PET imaging in our hands is similar to published reports. With a positive predictive value of 87%, a positive FDG study indicates a high likelihood that there is brain tumour present. A negative study does not exclude the presence of tumour. 相似文献
28.
29.
ABSTRACT We report an unusual case of bilateral chronic conjunctivitis and corneal scarring in a boy with X-linked hypogammaglobulinaemia (XLH) who did not respond to the usual antibacterial and antiviral therapy. An immunofluorescence test for Chlamydia trachomatis from an eye swab was strongly positive. Within days of commencement of local and systemic tetracycline therapy, he showed marked improvement. Since conjunctival follicle formation, which depends on the presence of a B-cell population, may not occur in XLH, clinical examination in chlamydia conjunctivitis may be misleading and lead to a delay in diagnosis and treatment with resulting corneal complications, unless laboratory evidence of chlamydia infection is specifically sought. 相似文献
30.
JB CARLIN P LANGDON SF HURLEY JB ZIEGLER R DOHERTY P CHONDROS JM KALDOR 《Journal of paediatrics and child health》1996,32(1):42-47
Objective : To describe survival patterns, use of health services and related costs for Australian children with perinatally acquired human immunodeficiency virus (HIV) infection.
Methodology : A retrospective cross-sectional survey was made of 20 children with HIV infection (91% of those diagnosed) and 13 children with maternal antibodies who subsequently seroreverted, treated at 10 medical centres. Details of disease progression and use of health services were obtained from hospital medical records. Monthly costs for three phases of infection were estimated by linking service usage rates with estimates of the unit cost of each service. The average lifetime cost was estimated by combining monthly costs and phase duration estimates from the literature.
Results : Patterns of disease progression were similar to those reported internationally, with a median survival of 8 years. Use, of health services increased with severity of illness. Mean monthly costs were $120 per month (1992 Australian dollars) for children with maternal antibodies who subsequently seroreverted, $320 per month for children with HIV infection but no acquired immunodeficiency syndrome (AIDS)-defining illness, and $1830 per month for children with AIDS. The present value of total lifetime cost for a child with HIV infection was $48174,46% of which was for treatment of AIDS.
Discussion : The mean lifetime cost for a perinatally infected child was just over half that for a man with HIV in Australia. Health service usage and costs were lower for Australian than American children with HIV. 相似文献
Methodology : A retrospective cross-sectional survey was made of 20 children with HIV infection (91% of those diagnosed) and 13 children with maternal antibodies who subsequently seroreverted, treated at 10 medical centres. Details of disease progression and use of health services were obtained from hospital medical records. Monthly costs for three phases of infection were estimated by linking service usage rates with estimates of the unit cost of each service. The average lifetime cost was estimated by combining monthly costs and phase duration estimates from the literature.
Results : Patterns of disease progression were similar to those reported internationally, with a median survival of 8 years. Use, of health services increased with severity of illness. Mean monthly costs were $120 per month (1992 Australian dollars) for children with maternal antibodies who subsequently seroreverted, $320 per month for children with HIV infection but no acquired immunodeficiency syndrome (AIDS)-defining illness, and $1830 per month for children with AIDS. The present value of total lifetime cost for a child with HIV infection was $48174,46% of which was for treatment of AIDS.
Discussion : The mean lifetime cost for a perinatally infected child was just over half that for a man with HIV in Australia. Health service usage and costs were lower for Australian than American children with HIV. 相似文献