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Postbiopsy renal transplant arteriovenous fistulas: color Doppler US characteristics 总被引:3,自引:0,他引:3
Color Doppler ultrasound (US) with point-spectral analysis was performed on eight patients with postbiopsy renal transplant arteriovenous fistulas. Waveform analysis of the supplying artery documented decreased resistive indices in all cases and increased flow velocities in seven. The peak-systolic flow velocity in the arteries supplying the fistulas ranged from 55 to 180 cm/sec (mean, 92 cm/sec), while the range in normal arteries was 20-52 cm/sec (mean, 32 cm/sec). The resistive indices of the arteries supplying the fistulas ranged from 0.31 to 0.50 (mean, 0.45), while the resistive indices of the normal arteries ranged from 0.60 to 0.92 (mean, 0.74). Arterialization of the venous waveform from the draining vein was also documented in all cases. In six cases, the increased flow velocities resulted in increased color saturation toward white in the supplying artery (n = 2) or in both the artery and the draining vein (n = 4), which was detectable on the realtime image. In six cases, flow turbulence resulted in localized tissue vibration, which appeared as random color assignment in extravascular renal parenchyma adjacent to the fistula. Knowledge of these imaging and Doppler characteristics should aid in the identification of renal transplant arteriovenous fistulas with color Doppler US. 相似文献
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Chronic pancreatitis: ultrasonic features 总被引:2,自引:0,他引:2
A retrospective analysis of 84 ultrasound examinations (in 77 patients) was performed to assess the frequency of sonographic findings in chronic pancreatitis. The findings included: inhomogeneously increased echogenicity in 53% of these examinations, focal or diffuse enlargement in 41%, focal dense echoes in 40%, pseudocyst formation in 21%, and a hypoechoic head mass in 7%. Thirteen per cent of our patients had a normal sonogram. Several presentations of chronic pancreatitis not previously described in the sonographic literature included: pancreatic or common bile duct enlargement or pseudocyst formation with otherwise normal-appearing glands. There was no direct relationship between the presence of focal high-intensity echoes within the pancreatic parenchyma and the presence of radiographic calcification. There was no difference in the frequency of ultrasonic abnormalities between patients with and without clinical evidence of pancreatic insufficiency. These results indicate that the sonographic findings in chronic pancreatitis are significantly more varied than previous reports would indicate. 相似文献
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Joel Jakobsson Maria Bjerke Carl Johan Ekman Carl Sellgren Anette GM Johansson Henrik Zetterberg Kaj Blennow Mikael Landén 《Neuropsychopharmacology》2014,39(10):2349-2356
Bipolar disorder (BD) is characterized by mood swings between manic and depressive states. The etiology and pathogenesis of BD is unclear, but many of the affected cognitive domains, as well as neuroanatomical abnormalities, resemble symptoms and signs of small vessel disease. In small vessel disease, cerebrospinal fluid (CSF) markers reflecting damages in different cell types and subcellular structures of the brain have been established. Hence, we hypothesized that CSF markers related to small vessel disease may also be applicable as biomarkers for BD. To investigate this hypothesis, we sampled CSF from 133 patients with BD and 86 healthy controls. The concentrations of neurofilament light chain (NF-L), myelin basic protein (MBP), S100B, and heart-type fatty acid binding protein (H-FABP) were measured in CSF and analyzed in relation to diagnosis, clinical characteristics, and ongoing medications. Hereby we found an elevation of the marker of subcortical axonal damage, NF-L, in bipolar subjects. We also identified positive associations between NF-L and treatment with atypical antipsychotics, MBP and lamotrigine, and H-FABP and lithium. These findings indicate axonal damage as an underlying neuropathological component of bipolar disorder, although the clinical value of elevated NF-L remains to be validated in follow-up studies. The associations between current medications and CSF brain injury markers might aid in the understanding of both therapeutic and adverse effects of these drugs. 相似文献
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Characterization of the effects of cultured vascular cells on the activation of blood coagulation 总被引:9,自引:0,他引:9
The coagulant properties of intact bovine vascular cells (aortic endothelial and smooth muscle cells) and human vascular cells (cutaneous and foreskin microvascular cells, umbilical venous endothelium) grown in vitro were studied. Compared to nonvascular cells (fibroblasts, corneal endothelial cells, fetal lung or intestinal mucosal cells), vascular cells had little procoagulant activity. Radioimmunologic measurement of thrombin in recalcified plasma demonstrated markedly lower concentrations of thrombin in the presence of vascular endothelial and smooth muscle cells compared to corneal endothelial and fetal lung cells. The low thrombin concentrations were not a consequence of thrombin binding to the vascular cells nor were they due to accelerated thrombin inactivation by antithrombin-III or alpha 2-macroglobulin. Neither vascular cells nor the nonvascular cells promoted contact activation of plasma as measured by a sensitive specific assay for kallikrein. Studies with intact cell monolayers and purified factors VIIa and X indicated that while nonvascular cells express tissue factor activity, vascular cells do not exhibit this property. These data suggest that the nonthrombogenic nature of intact vascular cells is due to their failure to initiate contact activation and to express tissue factor activity. In addition, the primary difference in coagulant potential between vascular cells and nonvascular cells is the lack of tissue factor expression by the vascular cells. 相似文献
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Two patients with hairy cell leukemia with massive splenomegaly and severe pancytopenia were treated with recombinant alpha-A interferon (IFN-alpha-2a). There was no significant response to a trial of IFN- alpha-2a (11 and 20 weeks) with respect to blood counts or spleen size. Subsequent treatment with 2'-deoxycoformycin (dCF) for 8 consecutive weeks (4 mg/m2/wk) resulted in normalization of spleen size and a normalization of peripheral blood counts and bone marrow in one patient. The second patient demonstrated a reduction in spleen size and improved blood counts following 9 weeks of dCF therapy but eventually became refractory. This demonstrates that dCF is non-cross-resistant with interferon and confirms the efficacy of dCF in nonsplenectomized patients. 相似文献
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GM Makhlouf 《Gastroenterology》1997,112(6):2111-2113
This article has no abstract. To view the article, select the "View Print Version (PDF)" link above. 相似文献
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