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Extramedullary hematopoiesis refers to the presence of hematopoietic elements in locations other than the bone marrow medullary space. It occurs as a compensatory mechanism to impaired hematopoiesis resulting from a variety of pathological conditions. Because of the hazards of biopsy of a highly vascular hematopoietic mass, it is desirable to establish the diagnosis noninvasively. We report a case where 18F-fluoro-3'deoxy-L-thymidine PET/CT and 99mTc-SC scintigraphy were used as a noninvasive modality to diagnose extramedullary hematopoiesis.  相似文献   
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Nutcracker fracture of the cuboid is a rare injury usually caused by forced abduction of the forefoot on a fixed hindfoot. We report a case of this fracture in a 58-year-old man who was treated on the principle of ligamentotaxis and the position being held with Kirchner wires for a period of 5 weeks. He recovered without any complications and with good ankle and subtalar movements. At 5 months following the injury he had returned to his previous occupation. We think this novel way of treating this rare fracture is simple and gave a good result in this patient.  相似文献   
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Stability studies of protein therapeutics are often accelerated by storing potential formulations at elevated temperatures where the rates of various chemical and physical degradation pathways are increased. An often overlooked caveat of using these studies is the potential degradation of the formulation components themselves. In this report, we show that the monoclonal antibody MAB001 aggregated at a faster rate when formulated with sucrose compared to samples that contained sorbitol or no excipient during accelerated stability studies following an initial lag phase where the rates of aggregate formation were similar in all formulations. The duration of the lag phase was both pH and temperature dependent and a significant increase of protein glycation was noticed during this time. These observations indicate that the enhanced rate of antibody aggregation in sucrose containing formulations is likely due to protein glycation following sucrose hydrolysis under accelerated conditions. This hypothesis was confirmed by demonstrating that antibody directly glycated with glucose aggregated at a faster rate than nonglycated antibody stored in the identical formulation. These findings question the utility of using accelerated stability data for predicting protein stability in sucrose containing formulations stored at 2–8°C, where no glycation or change in aggregation rate was observed. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:4501–4510, 2009  相似文献   
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OBJECTIVE: To study the prevalence of thrombophilic conditions in patients with acute and chronic portal vein thrombosis (PVT) and to compare it with those in patients suffering from deep vein thrombosis (DVT) after lower limb arthroplasty and in healthy subjects. METHODS: Twenty-six patients with spontaneous PVT (20 chronic, 6 acute) with normal liver function and not receiving anticoagulants were evaluated for thrombophilic conditions. Levels of protein C, protein S and antithrombin were compared with those in 50 healthy controls. Factor V gene 'Leiden' mutation (FVL) and high homocysteine levels were looked for in patients with PVT and in 18 patients developing post-arthroplasty lower limb DVT despite anticoagulation. RESULTS: Of 26 patients with PVT, 19 had at least one thrombotic condition (acute PVT 5/6, chronic PVT 14/20) and 12 had more than one such condition; in comparison, of 18 patients with DVT, eight had one thrombophilic condition and one had two such conditions (p=0.03). Patients with PVT had significantly lower levels of protein C, protein S and antithrombin than healthy subjects and those with DVT. Six patients had Factor VIII levels above 150%; four had elevated homocysteine levels and three had detectable anti-cardiolipin antibodies. Three patients with PVT (acute 2, chronic 1) were heterozygous for FVL mutation. CONCLUSIONS: Underlying thrombophilic conditions are common in Indian patients with spontaneous PVT. In many patients, multiple thrombophilic conditions are present and these may play a role in the pathogenesis of PVT.  相似文献   
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Evolution of social behavior through interpopulation selection   总被引:2,自引:2,他引:0       下载免费PDF全文
Under certain special conditions natural selection can be effective at the level of local populations, or demes. Such interpopulation selection will favor genotypes that reduce the probability of extinction of their parent population even at the cost of a lowered inclusive fitness. Such genotypes may be characterized by altruistic traits only in a viscous population, i.e., in a population in which neighbors tend to be closely related. In a non-viscous population the interpopulation selection will instead favor spiteful traits when the populations are susceptible to extinction through the overutilization of the habitat, and cooperative traits when it is the newly established populations that are in the greatest danger of extinction.  相似文献   
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