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The aim of the current research project was to explore the possibilities of combining pressurized carbon dioxide with hot stage extrusion during manufacturing of solid dispersions of itraconazole and polyvinylpyrrolidone-co-vinyl acetate 64 (PVP-VA 64) and to evaluate the ability of the pressurized gas to act as a temporary plasticizer as well as to produce a foamed extrudate. Pressurized carbon dioxide was injected into a Leistritz Micro 18 intermeshing co-rotating twin-screw melt extruder using an ISCO 260D syringe pump. The physicochemical characteristics of the extrudates with and without injection of carbon dioxide were evaluated with reference to the morphology of the solid dispersion and dissolution behaviour and particle properties. Carbon dioxide acted as plasticizer for itraconazole/PVP-VA 64, reducing the processing temperature during the hot stage extrusion process. Amorphous dispersions were obtained and the solid dispersion was not influenced by the carbon dioxide. Release of itraconazole from the solid dispersion could be controlled as a function of processing temperature and pressure. The macroscopic morphology changed to a foam-like structure due to expansion of the carbon dioxide at the extrusion die. This resulted in increased specific surface area, porosity, hygroscopicity and improved milling efficiency.  相似文献   
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The goal of this longitudinal study was to investigate the precursors of early reading development in 52 children with cerebral palsy at kindergarten level in comparison to 65 children without disabilities. Word Decoding was measured to investigate early reading skills, while Phonological Awareness, Phonological Short-term Memory (STM), Speech Perception, Speech Production and Nonverbal Reasoning were considered reading precursors. Children with cerebral palsy lag behind on all reading precursors at the beginning of the second year of kindergarten. For the children without disabilities, early reading skills in Grade 1 were best predicted by Phonological Awareness and Phonological STM while Speech Production was the most important predictor of early reading success for the children with cerebral palsy, followed by Phonological Awareness and Speech Perception. Furthermore, for children with cerebral palsy, Speech Production appears to dominate reading development, as Speech Production measured at the beginning of the second year of kindergarten was strongly predictive of all other reading precursors measured at the end of the second year of kindergarten. The results of this study reveal that children with cerebral palsy with additional speech impairments are at risk for limited literacy development. Clinical implications are discussed.  相似文献   
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The effects on seizures, EEG and behavior of the non-NMDA receptor antagonist CNQX (6-cyano-7-nitroquinoxaline-2,3-dione), were studied in the WAG/Rij rat with absence epilepsy. Intracerebroventricular injections (10, 50, and 100 nmol/5 microliters CNQX) showed that CNQX decreases the number of spike wave discharges in a dose-dependent way. Coinjection of CNQX (100 nmol/5 microliters) and AMPA (0.1 pmol/5 microliters), kainic acid (0.01 nmol/5 microliters) or NMDA (50 pmol/5 microliters) attenuated the CNQX response, indicating that CNQX acts on both non-NMDA and NMDA receptors. The observed effects appear to be specific manipulations of the epilepsy not mediated by behavioral changes.  相似文献   
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Lymphoma in immunocompromised transplant patients is a feared cause of morbidity and mortality. Superimposed on the lymphoma and the transplantation immunosuppression is a rare condition: hemophagocytic syndrome (HS). HS is characterized by fever, hepatosplenomegaly and lymphadenopathy, skin rashes, jaundice, coagulopathy, and phagocytosis of blood elements with pancytopenia. Here we describe a rare but fatal case of a kidney transplant patient who developed T-cell lymphoma and HS, without evidence of EBV replication. A short review of the diagnosis, treatment, and prognosis of HS is given. Received: 4 March 1997 Received after revision: 6 June 1997 Accepted: 30 June 1997  相似文献   
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We report a 12-year-old boy presenting with smooth muscle antibody-positive auto-immune chronic active hepatitis. Suspicion of the diagnosis arose after a routine blood test which revealed abnormal liver function tests. In spite of the presence of cirrhosis and patchy necrosis on liver biopsy, our patient never showed any clinical feature of impaired liver function. This observation demonstrates that auto-immune hepatitis may exist for a long time before clinical symptoms appear and probably explains why some cases of auto-immune hepatitis finally present as fulminant liver failure.  相似文献   
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Background: Recent development of extracorporeal magnetic stimulation (ECMS) which uses current‐changing magnetic fields allows the induction of electrical stimulation in the desired deep tissue. Recent study showed the sacral nerve stimulation reduces corticoanal excitability that may play a functional role in anal continence mechanisms. Preliminary study shows that ECMS of sacral nerve can modify pelvic floor function and expel rectal balloon in patients with pelvic floor dyssynergia (PFD). Aims: To evaluate the effect of ECMS compared with biofeedback therapy (BF) in patients with PFD. Methods and Materials: Thirty‐eight patients who fulfilled Rome II criteria for PFD by colon transit time and anorectal function tests, were randomly treated with 8 sessions of ECMS (2/weeks; n = 19) at prone position or BF (2/weeks; n = 19) at sitting position. Stimulation parameters were set at 50–80% of maximum intensity, 10 and 50 Hz frequency, 3 s burst length with 3 and 6 s off using arm‐typed stimulator (BioCom‐1000, Mcube Co., Korea). Symptom scores for constipation with/without anorectal function test were repeatedly measured after each treatment. Response was defined as 50% or more decreased symptom score after treatment (partial response: 30–50%, poor: <30%). Results: Fifteen patients (age 49.1 ± 13.4 years, mean ± SD; 4 men) completed 8 session of BF and 14 patients (54.5 ± 17.6 years, 3 men) completed 8 session of ECMS. Four patients of BF group discontinued treatment due to unsatisfactory therapeutic effect (n = 1) and withdrew consent (n = 3) and 5 patients of ECMS group discontinued treatment because of same reasons (n = 1, 4). Total symptom scores were significantly decreased after treatment of 8 session in both treatment groups (13.4 ± 6.6 vs. 4.3 ± 4.0 for BF, p = 0.009; 14.9 ± 5.6 vs. 3.4 ± 4.0 for ECMS, p < 0.001). Bowel movements per week were also significantly increased after treatment in both groups (median 2 vs. 7 for BF, p = 0.035; median 2 vs. 7 for ECMS, p = 0.008). Thirteen out of 15 patients showed response in BF group and 12 out of 14 showed good response in ECMS group. No adverse effects in both groups. Conclusions: ECMS is as effective as BF for the treatment of PFD. Long‐term effect of ECMS for the patients with pelvic floor dyssynergia need to be evaluated in the near future.  相似文献   
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