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1.
A new range of stand magnifiers has been released by the COIL company in the United Kingdom. Examination of these magnifiers reveals that they fail to deliver the rated magnifications labelled prominently on the appliances, as a result of the manufacturer's conformance with the requirements of the German DIN standard and the use of back vertex power (F'v) rather than equivalent dioptric power (Fm) of the magnifier. In this study we provide information on the optometric parameters of these new stand magnifiers that will assist the more accurate specification of improvements in vision expected from their use. 相似文献
2.
Geert Verreck Annelies Decorte Koen Heymans Jef Adriaensen Dirk Cleeren Adri Jacobs Dehua Liu David Tomasko Albertina Arien Jef Peeters Patrick Rombaut Guy Van den Mooter Marcus E Brewster 《European journal of pharmaceutical sciences》2005,26(3-4):349-358
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
3.
Marieke Peeters Ludo Verhoeven Jan de Moor Hans van Balkom 《Research in developmental disabilities》2009,30(4):712-726
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
4.
5.
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
6.
P. Peeters J. Sennesael H. De Raeve M. De Waele D. Verbeelen 《Transplant international》1997,10(6):471-474
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
7.
8.
Glen Husada Katleen Libberecht Tom Peeters Jacques Populaire 《European Journal of Trauma》2005,31(1):68-71
Abstract
Background:
Osteoporosis is characterized by low bone density and poor bone mineralization. Mid-diaphyseal stress (insufficiency) fractures of the femur caused by osteoporosis are rare. The symptoms of these lesions are vague and confusing. The physician must be alert to the possibility of femoral shaft stress fractures when evaluating an elderly patient complaining of back, hip or leg pain.
Case Study:
A 72-year-old osteoporotic female patient with bilateral mid-diaphyseal stress fractures of the femur is reported. The diagnosis of femoral shaft stress fracture in the elderly is very difficult when based on physical findings and plain radiography only. A magnetic resonance imaging (MRI) scan or nuclear scintigraphy is necessary for early diagnosis. In the described case, the patient had an excellent result after surgical treatment with intramedullary nails.
Conclusion:
MRI or nuclear scintigraphy must be obtained to exclude the possibility of femoral shaft stress fractures in the elderly. In the absence of contraindications, surgery is the best solution for this kind of lesion. 相似文献
9.
10.
Peripheral stents aim to support revascularization procedures for intravascular stenoses by mechanically preventing vessel recoil and counteracting the pathophysiological process of luminal renarrowing triggered by procedural injury to the vessel wall. Despite improvements in stenting techniques and concomitant medication, repeated intervention due to target lesion restenosis is necessary in a significant percentage of patients. The permanent presence of an artificial implant plays a prominent role in the discussion of the mechanisms causing in-stent restenosis. Permanent metallic implants pose the risk of a continuous interaction between a non-absorbable stent and surrounding tissue, leading to physical irritation, long-term endothelial dysfunction, or chronic inflammatory reactions. In addition, there is a risk of stent fracture due to external mechanical forces. To overcome these shortcomings, stenting technology has moved towards the development of temporary implants composed of biocompatible materials which mechanically support the vessel during the period of high risk for recoil, and then completely degrade in the long-term. This removes a potential trigger for late restenosis. 相似文献