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The contents of total lipids, total sterols, total and individual phospholipids: lysophosphatidyl choline, lysophosphatidyl ethanolamine, phosphatidyl choline, phosphatidyl ethanolamine and alkali-stable phospholipids I and II, were significantly lower in mature cysts of Acanthamoeba culbertsoni strain A-1 than in trophozoites. The major constituent sterols of trophozoites, viz. ergosterol, 7-dehydrostigmasterol and 7,22,25-tridehydrostigmasterol which resolved as a single spot on thin-layer chromatography, disappeared in the cysts. When trophozoites grown in the presence of [14C]acetate were transferred to encystation medium, there was a steady decrease in the radioactivity in the lipids and acid-soluble fraction (glycogen) of the encysting cells while the radioactivity increased in the akali-insoluble fraction (cellulose). The activity of isocitrate lyase in the encysting cells steadily increased up to 24 h of encystation, followed by a slight decrease during 24-32 h, but the activity of isocitrate dehydrogenase steadily decreased up to 32 h of encystation, beyond which time no enzyme activity was detected. Inhibitors of isocitrate lyase, glycolate and maleate at 8.5 to 34 mM concentration inhibited encystation by 18-67%.  相似文献   
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Venous thrombosis is rare in children. It can be either acquired or of constitutional origin. Thrombosis during non-Hodgkin lymphoma remains exceptional and is usually locally associated to the tumoral process, raising the issue of its tumoral or cruoric nature. The treatment is based on anticoagulation concomitantly to chemotherapy. We report on a 4-year-old boy admitted for mediastinal non-Hodgkin lymphoma, who developed a thrombosis of the superior vena cava associated to protein S-deficiency. The mechanism of thrombosis may have been multifactorial: associated protein S-deficiency, vascular compression, tumoral process and chemotherapy.  相似文献   
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Recombinant activated factor VII has been Food and Drug Administration approved to treat hemorrhages in hemophiliac patients with inhibitors and in acquired hemophilia patients. Recombinant activated factor VII use has also been considered for the management of uncontrolled bleeding in a number of congenital and acquired hemostatic abnormalities. The myeloproliferative disorders are a group of clonal hematologic diseases where, frequently, abnormal platelet function is considered a hallmark. This is the first case report addressing the clinical benefit of off-label use of recombinant activated factor VII in an attempt to control intractable bleeding in a patient with a myeloproliferative disorder after splenectomy.  相似文献   
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Objective. – To describe the clinical and radiological features of foot involvement in patients with psoriatic arthritis.Methods. – We retrospectively reviewed the medical records of patients admitted between 1972 and 1999 for psoriatic arthritis with involvement of the foot. We included all patients who had peripheral and/or axial, asymmetric, chronic inflammatory joint disease meeting or not Avila's radiological criteria for psoriatic arthritis, with or without other imaging findings suggestive of psoriatic arthritis and with or without psoriasis.Results. – Twenty-six patients were included. Inflammatory heel pain was reported by 14 patients, whereas forefoot involvement was found in only seven patients. Sausage toe was present in two patients. None of the patients had Bauer's toe (combining arthritis and psoriatic skin and/or nail changes) or psoriatic onychopachydermoperiostitis of the great toe. Radiological abnormalities were found in 20 patients. Half the patients had calcaneal changes. Osteoperiostitis of the great toe was noted in two patients and mushrooming in five.Discussion. – The features of psoriatic arthritis in Morocco seem similar to those in other countries. Hindfoot involvement was present in 53% of patients. Involvement of the forefoot was rarely recorded in the charts, suggesting missed cases because of insufficient attention to the forefoot during the physical examination and availability of anteroposterior radiographs only. Oblique views (Hirtz and Chaumet) should be obtained because they give a clearer image of the distal part of the toes, which is often difficult to analyze on anteroposterior films.  相似文献   
28.
Neurturin (NTN) is a potent survival factor for midbrain dopaminergic neurons. CERE-120, an adeno-associated virus type 2 (AAV2) vector encoding human NTN (AAV2-NTN), is currently being developed as a potential therapy for Parkinson's disease. This study examined the bioactivity and safety/tolerability of AAV2-NTN in the aged monkey model of nigrostriatal dopamine insufficiency. Aged rhesus monkeys received unilateral injections of AAV2-NTN into the caudate and putamen, with each animal therefore serving as its own control. Robust expression of NTN within the nigrostriatal system was observed 8 months postadministration. (18)F-fluorodopa imaging using positron emission tomography revealed statistically significant increases in (18)F-fluorodopa uptake in the injected striatum compared with the uninjected side at 4 and 8 months. In addition, at 8 months postadministration, a significant enhancement in tyrosine hydroxylase immunoreactive fibers and an increase in the number of tyrosine hydroxylase immunoreactive cells was observed in the AAV2-NTN injected striatum compared with the uninjected side. Robust activation of phosphorylated extracellular signal-regulated kinase immunoreactivity in the substantia nigra was also observed. Histopathological analyses revealed no adverse effects of AAV2-NTN in the brain. Collectively, these results are consistent with the neurotrophic effects of NTN on the dopaminergic nigrostriatal system and extend the growing body of evidence supporting the concept that AAV2-NTN may have therapeutic benefit for Parkinson's disease.  相似文献   
29.
The development of therapeutic options for rectal cancer strives to reach the ultimate goals of improved local control and overall survival. However, preserving continence, as well as genitourinary and sexual function, remains elusive in some patients. Loss of bowel control may be the most unsettling factor in terms of quality of life. Patients must be accurately informed about the surgery’s possible adverse effects, and surgeons must offer the best options (e.g. colostomy bag or sphincteroplasty) in order to minimize these complaints.  相似文献   
30.
In this paper we describe the design and synthesis of 18 derivatives of the antimicrobial atovaquone which were substituted at the 3-hydroxy group by ester and ether functions. The compounds were evaluated in vitro for their activity against the growth of Plasmodium falciparum, the malaria causing parasite. All the compounds showed potent activity, with IC50 values in the range of 1.25–50 nM, comparable to those of atovaquone and much higher than chloroquine or quinine.  相似文献   
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