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Spontaneous and surgery-associated bleeding in patients with von Willebrand disease (vWD) cannot always be controlled with desmopressin or replacement therapy. This paper presents results on the use of recombinant-activated factor VII (rFVIIa) in patients with vWD included in the internet registry Haemostasis.com. Twenty-eight reports on the use of rFVIIa in vWD were identified from the database and included in this analysis. The bleeding episodes were classified as mild (n = 7), moderate (n = 16), or severe (n = 2), and were unspecified in three cases. The median dose of rFVIIa administered was 94 microg/kg body weight (40-127.3 microg/kg). Bleeding stopped in 23 of 27 evaluable patients (85%) and markedly decreased in three patients; the total response rate was 96% (26/27 patients). Response did not correlate with the type of vWD, the site or severity of the initial bleed, or the rFVIIa dose. Other replacement therapies were infrequently used, and their use was similar in the 24 h before and after rFVIIa administration. Eighteen patients also received antifibrinolytic treatment, but its impact on response was not recorded. Only one adverse event (mild fever) was observed. These cases suggest a role for rFVIIa as a safe and effective therapy for vWD.  相似文献   
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We examined binding of 3H-phorbol dibutyrate (3H-PDBu) to gel filtered human platelets (GFP) and discovered that GFP possess two classes of receptors for phorbol diesters (PDE). High-affinity (HA) receptors, approximately 5000/GFP, bound 3H-PDBu with an apparent dissociation constant (KD) of approximately 12 nM. Low-affinity receptors were approximately 5 times more numerous (2.4 × 104/GFP) and had a 10-fold lower affinity for 3H-PDBu (apparent KD = 115 nM). The potencies of phorbol myristate acetate (PMA) and PDBu paralleled their binding affinities to the PDE receptors. Teleocidin (Tel), although structurally distinct from PDE, competed with 3H-PDBu for its HA-receptors (KI Tel = 1.9 nM). Binding of PDE to HA- or LA- receptors was rapid, reversible, saturable and stereospecific. The HA- and LA-receptors modulated different platelet responses. HA-receptors regulated the secretion of β-thromboglobulin from -granules and the release of N-acetyl-β-D-hexosaminidases from lysosomes. LA-receptors mediated both platelet aggregation and the release of serotonin from dense granules. This is the first demonstration of two physiologically active classes of PDE/Tel receptors in human platelets, and demonstrates that particular platelet responses may be directed by distinct classes of receptors for specific agonists.  相似文献   
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BACKGROUND: Mutations in the human SLC4A1 (AE1/band 3) gene are associated with hereditary spherocytic anaemia and with distal renal tubular acidosis (dRTA). The molecular diagnosis of AE1 mutations has been complicated by the absence of highly polymorphic genetic markers, and the pathogenic mechanisms of some dRTA-associated AE1 mutations remain unclear. Here, we characterized a polymorphic dinucleotide repeat close to the human AE1 gene and performed an immunocytochemical study of kidney tissue from a patient with inherited dRTA with a defined AE1 mutation. METHODS: One CA repeat region was identified in a phage P1-derived artificial chromosome (PAC) clone containing most of the human AE1 gene and the upstream flanking region. We determined its heterozygosity value in multiple populations by PCR analysis. Genotyping of one family with dominant dRTA identified the AE1 R589H mutation, and family member genotypes were compared with the CA repeat length. AE1 and vH(+)-ATPase polypeptides in kidney tissue from an AE1 R589H patient were examined by immunocytochemistry for the first time. RESULTS: This CA repeat, previously reported as D17S1183, is approximately 90 kb upstream of the AE1 gene and displayed considerable length polymorphism, with small racial differences, and a heterozygosity value of 0.56. The allele-specific length of this repeat confirmed co-segregation of the AE1 R589H mutation with the disease phenotype in a family with dominant dRTA. Immunostaining of the kidney cortex from one affected member with superimposed chronic pyelonephritis revealed vH(+)-ATPase-positive intercalated cells in which AE1 was undetectable, and proximal tubular epithelial cells with apparently enhanced apical vH(+)-ATPase staining. CONCLUSIONS: The highly polymorphic dinucleotide repeat adjacent to the human AE1 gene may be useful for future studies of disease association and haplotype analysis. Intercalated cells persist in the end-stage kidney of a patient with familial autosomal dominant dRTA associated with the AE1 R589H mutation. The absence of detectable AE1 polypeptide in those intercalated cells supports the genetic prediction that the AE1 R589H mutation indeed causes dominant dRTA.  相似文献   
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The influence of partial hepatectomy on the genotoxic effect of aflatoxin B1 (AFB1) mycotoxin in male Chinese hamsters (Cricetulus griseus) was studied after application of a single i.p. dose of 1.0 mg AFB1/kg. Changes in the fractions of proliferating bone marrow cells, values of the mitotic index of liver cells and morphologic changes in liver tissue were also monitored. Partial hepatectomy reduced significantly the mutagenic activity of AFB1 measured by the frequency of chromosome aberrations in bone marrow cells during 5 days. In hepatectomized animals AFB1 cytotoxicity was significantly reduced as evaluated by changes in the values of proliferating bone marrow cell fractions. There were no important morphologic changes in the liver. In hepatectomized AFB1 treated animals mitotic activity in liver tissue was substantially lower than in hepatectomized but AFB1 untreated animals.  相似文献   
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Parallel image reconstruction using B-spline approximation (PROBER).   总被引:1,自引:0,他引:1  
A new reconstruction method for parallel MRI called PROBER is proposed. The method PROBER works in an image domain similar to methods based on Sensitivity Encoding (SENSE). However, unlike SENSE, which first estimates the spatial sensitivity maps, PROBER approximates the reconstruction coefficients directly by B-splines. Also, B-spline coefficients are estimated at once in order to minimize the reconstruction error instead of estimating the reconstruction in each pixel independently (as in SENSE). This makes the method robust to noise in reference images. No presmoothing of reference images is necessary. The number of estimated parameters is reduced, which speeds up the estimation process. PROBER was tested on simulated, phantom, and in vivo data. The results are compared with commercial implementations of the algorithms SENSE and GRAPPA (Generalized Autocalibrating Partially Parallel Acquisitions) in terms of elapsed time and reconstruction quality. The experiments showed that PROBER is faster than GRAPPA and SENSE for images wider than 150x150 pixels for comparable reconstruction quality. With more basis functions, PROBER outperforms both SENSE and GRAPPA in reconstruction quality at the cost of slightly increased computational time.  相似文献   
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INTRODUCTION: Major or complicated pancreatic trauma in children is uncommon and management strategies remain controversial. The aim of this study was to evaluate our experience with both early and delayed surgery in these pediatric cases. METHODS: We carried out a retrospective analysis of data of pediatric patients with major or complicated pancreatic injury operated on between January 1994 and December 2005 in our pediatric trauma center. RESULTS: Thirteen children (9 boys and 4 girls) with a mean age of 8.5 years (range 3 - 16 years) were operated for major or complicated pancreatic injury. The extent of injury was: grade II (major contusion without duct injury or tissue loss) in 4 children; grade III (distal transection) in 5 children and grade IV injury (proximal transection) in four patients. Pseudocyst developed in 8 children: 4 with grade II injury, 2 with grade III injury and 2 with grade IV injury (one with abdominal pseudocyst and one with an abdominal and a mediastinal pseudocyst). Early diagnosis and operation was achieved in 5 cases, while delayed diagnosis and operation occurred in 8. Three children underwent cystogastrostomy; 6 had a spleen-sparing distal pancreatectomy and 4 had resection with Roux-en-Y jejunostomy drainage. Endoscopic retrograde cholangiopancreaticography (ERCP) was the most useful diagnostic tool in assessing ductal injury. There were no deaths or long-term morbidity in our group of patients. CONCLUSIONS: Our results support the view that early operation is important in ductal pancreatic injury. We recommend transferring children with a suspected ductal injury to a tertiary center with experience in both pediatric ERCP and pancreatic surgery.  相似文献   
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Vernal catharr of the conjunctivae is frequently the initial symptom of dermorespiratory syndrome. In all nine children where ophthalmological and other manifestations of varying extent of general atopy were combined, the authors revealed a marked increase of immunoglobulin IgE 220-2230 I.U./ml (normal values up to 150 I.U./ml) and polyvalent allergy. In the treatment of vernal catharr the authors used a combination of antihistaminics and preventive immunopharmaceutical preparations administered locally (Spersallerg and Opticrom) or as general medication (Hismanal and Zaditen), supplemented by aimed hyposensitization. In acute stages of the inflammation of the eye the authors administered Triamcinolon into the upper transient conjunctival fold. In the treatment of secondary infection Garasone was most effective. A finding interesting from the immunological aspect was vernal catharr without general symptoms of atopy in a patient with hypogammaglobulinaemia IgA.  相似文献   
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