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11.
M. DALRYMPLE-HAY R. AITCHISON P. COLLINS M. SEKHAR B. COLVIN 《International journal of laboratory hematology》1992,14(3):209-211
Hydroxyethyl starch (HES) (Hespan, DPont) is a widely used synthetic volume expander which in standard doses of up to 1.51 in 24 h has no significant effect on coagulation (Munsch et al. 1988). However, the data sheet states that in large volumes HES may alter the coagulation mechanism. We now report a case of HES induced acquired von Willebrand's disease (vWD) in which severe bleeding occurred. 相似文献
12.
目的 探讨急性胰腺炎患者血浆vW因子的变化及其临床意义。方法 采用双抗体夹心固相酶免疫法测定 3 5例急性胰腺炎患者和 3 0名健康献血者的血浆vW因子水平 ,对其进行相关性分析。结果 急性胰腺炎患者入院后 2 4h血浆vW因子水平为 2 15 .0 %± 2 3 .4% ,显著高于正常对照组 10 7.5 %± 2 9.6% (P <0 .0 0 1) ;重症急性胰腺炎患者血浆vW因子显著高于轻型急性胰腺炎患者 (P <0 .0 1) ;血浆vW因子预测重症AP的敏感性、特异性和准确性分别是 91.7%、87.0 %和 88.7%。结论 急性胰腺炎患者存在血管内皮损伤 ;测定急性胰腺炎患者血浆vW因子水平可早期预测病情的严重程度 相似文献
13.
We report experimental evidence for substantial individual differences in the susceptibility to simultaneous colour contrast. Interestingly, we found that not only the general amount of colour induction varies across observers, but also the general shape of the curves describing asymmetric matching data. A simple model based on von Kries adaptation and crispening describes the data rather well when we regard its free parameters as observer specific. We argue that the von Kries component reflects the action of a temporal adaptation mechanism, while the crispening component describes the action of the instantaneous, purely spatial mechanism most appropriately labeled simultaneous colour contrast. An interesting consequence of this view is that traditional ideas about the general characteristics of simultaneous contrast must be considered as misleading. According to Kirschmann’s 4th law, for instance, the simultaneous contrast effect should increase with increasing saturation of the surround, but crispening predicts the converse. Based on this reasoning, we offer a plausible explanation for the mixed evidence on the validity of Kirschmann’s 4th law. We also argue that simultaneous contrast, the crispening effect, Meyer’s effect and the gamut expansion effect are just different names for the same basic phenomenon. 相似文献
14.
Summary. Background: Pathological shear stress induces platelet aggregation that is dependent on von Willebrand factor (VWF) binding to glycoprotein (Gp)Ib‐IX‐V and phosphatidylinositol 3‐kinase activation. We tested the hypothesis that pathological shear stress stimulates phosphatidylinositol 3,4,5‐trisphosphate (PIP3) synthesis by directing the assembly of a molecular signaling complex that includes class IA phosphatidylinositol 3‐kinase (PI 3‐KIA). Methods: Platelets were subjected to 120 dynes cm?2 shear stress in a cone‐plate viscometer. Resting and sheared platelets were lyzed, immunoprecipitations of PI 3‐KIA performed, or lipids extracted for PIP3 measurements. α‐Actinin was incubated with phosphatidylinositol 4,5‐bisphosphate (PIP2), immunoprecipitated, and used as a substrate for in vitro PI 3‐KIA activity. Results: Pathological shear stress induces biphasic PIP3 production. In resting platelets, PI 3‐KIA associates with α‐actinin and PIP2. After exposure to shear stress, α‐actinin and PIP2 rapidly disassociate from PI 3‐KIA. PI 3‐KIA then gradually re‐associates with PIP2 and α‐actinin, and this complex becomes linked to GpIbα through the cytoskeleton. PIP3 production and the observed changes in the association between α‐actinin, PIP2, and PI 3‐KIA are inhibited when VWF binding to GpIbα is blocked. In a cell‐free system, α‐actinin binds PIP2 and when the α‐actinin–PIP2 complex is added to platelet PI 3‐KIA, PIP3 production is stimulated. Conclusions: These results suggest that pathological shear‐induced VWF binding to GpIb‐IX‐V stimulates PIP3 production through the assembly of an α‐actinin‐based complex that colocalizes PI 3‐KIA with substrate PIP2. 相似文献
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17.
Gastrointestinal manifestations of type 1 neurofibromatosis (von Recklinghausen''s disease) 总被引:5,自引:0,他引:5
Gastrointestinal involvement in von Recklinghausen's disease occurs in three principal forms: hyperplasia of the submucosal and myenteric nerve plexuses and mucosal ganglioneuromatosis which leads to disordered gut motility; gastrointestinal stromal tumours showing varying degrees of neural or smooth muscle differentiation; and a distinctive glandular, somatostatin-rich carcinoid of the periampullary region of the duodenum that contains psammoma bodies and which may be associated with phaeochromocytoma. This review describes the histopathological features of these lesions and discusses potential pitfalls in their differential diagnosis. Their accurate identification has significant implications for clinical management and may even provide the first pointer to the diagnosis of neurofibromatosis. 相似文献
18.
Zusammenfassung Beschrieben wird eine radioimmunologische Methode zum Nachweis der Prostaglandin F2 alpha-Menge in Schnittwunden der Haut von Meerschweinchen. Bei zu Lebzeiten zugefügten Hautverletzungen finden sich schnell ansteigende Prostaglandin F2 alpha-Mengen, die 1 Stunde nach der Verletzung bis 71 ng/g erreichen. Nach der Tötung der Tiere sinken die konstatierten Mengen in zu Lebzeiten gesetzten Wunden allmählich ab und erreichen in der 6. Std nach dem Tode 17 ng/g. In postmortal zugefügten Verletzungen, die spätestens bis zur 8. Std nach dem Tode gesetzt wurden, findet man eine Menge des untersuchten Prostaglandins in Höhe von etwa 14–18 ng/g. In späteren postmortalen Wunden beträgt die Menge dieses Prostaglandins etwa 9–10 ng/g. Die Unterschiede erlauben es, die Untersuchung des Prostaglandins F2 alpha zum Beweis dafür anzuwenden, ob eine Hautwunde zu Lebzeiten zugefügt wurde und wieviel Zeit danach vergangen ist. 相似文献
19.
Michael Z. Gilcrease MD PhD Laura Schmidt PhD Berton Zbar MD Luan Truong MD Michael Rutledge MD Thomas M. Wheeler MD 《Human pathology》1995,26(12)
Papillary cystadenoma of the epididymis is an uncommon benign lesion that may occur sporadically or as a manifestation of von Hippel—Lindau (VHL) disease. Neither immunohistochemical studies nor molecular genetic analyses of the VHL gene have been reported previously for this lesion. The authors describe two cases of clear cell papillary cystadenoma of the epididymis, both of which were initially confused with metastatic renal cell carcinoma. Both lesions showed positive immunohistochemical staining for low and intermediate molecular weight keratins (Cam 5.2 and AE1/AE3), EMA, vimentin, α1-antitrypsin, and α1-antichymotrypsin. Each was negative for CEA. Because clear cell papillary cystadenoma is similar to renal cell carcinoma histologically, and because both occur as components of the von Hippel—Lindau disease complex, the authors analyzed both cases for the presence of mutations in the VHL gene. A somatic VHL gene mutation was detected in one of the two tumors by polymerase chain reaction followed by single-strand conformation polymorphism analysis. Direct sequencing revealed a cytosine to thymine transition at nucleotide 694, resulting in the replacement of an arginine with a stop codon after the sixth amino acid of exon 3. As the VHL gene is believed to function as a tumor suppressor gene, VHL gene mutations may play a role in the initiation of tumorigenesis in sporadic cystadenomas of the epididymis. 相似文献
20.
Soluble cell adhesion molecules and von Willebrand factor in children with Kawasaki disease. 总被引:4,自引:0,他引:4
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Fifty-nine children with acute Kawasaki disease (KD), a childhood vasculitis, were compared with 35 children with fever due to infection and 48 healthy children. Levels of soluble E-selectin (sE-selectin), soluble intercellular adhesion molecule-1 (sICAM-1), and soluble vascular cell adhesion molecule-1 (sVCAM-1) in the healthy children were double those found in adults. All three soluble cell adhesion molecules and von Willebrand factor (vWF) were higher in the children with KD than in the healthy children, but only sE-selectin, a marker for activated endothelial cells, and sICAM-1 were higher than in the febrile children. The high levels of vWF in KD appear to reflect the prominent acute-phase reaction. This information can help us to understand further the complex interactions between cytokines, circulating inflammatory cells and the vascular endothelium, and may lead to new therapeutic avenues in KD and other inflammatory diseases and vasculitides. 相似文献