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21.
R Kapur BJ Spargo MS Chen JM Calvert AS Rudolph 《Canadian Metallurgical Quarterly》1996,33(4):205-216
A new method is described for producing biomedically relevant polymers with precisely defined micron scale surface texture in the x, y, and z planes. Patterned Si templates were fabricated using photolithography to create a relief pattern in photoresist with lateral dimensions as small as 1 micron. Electroless Ni was selectively deposited in the trenches of the patterned substrate. The Ni served as a resilient mask for transferring the patterns onto the Si substrate to depths of up to 8.5 microns by anisotropic reactive ion etching with a fluorine-based plasma. The 3-dimensional (3-D) textured silicon substrates were used as robust, reusable molds for pattern transfer onto poly (dimethyl siloxane), low density poly (ethylene), poly (L-lactide), and poly (glycolide) by either casting or injection molding. The fidelity of the pattern transfer from the silicon substrates to the polymers was 90 to 95% in all three planes for all polymers for more than 60 transfers from a single wafer, as determined by scanning electron microscopy and atomic force microscopy. Further, the 3-D textured polymers were selectively modified to coat proteins either in the trenches or on the mesas by capillary modification or selective coating techniques. These selectively patterned 3-D polymer substrates may be useful for a variety of biomaterial applications. 相似文献
22.
AS Planting ME van der Burg M de Boer-Dennert G Stoter J Verweij 《Canadian Metallurgical Quarterly》1993,68(4):789-792
Twenty-five patients with advanced solid tumours were entered in a phase I/II study of six, weekly cycles of cisplatin. Nineteen patients were chemonaive and six were previously treated. The starting dose was 50 mg m-2 week-1. This dose could be escalated without major toxicity to 70 mg m-2 week-1. At a dose of 80 mg m-2 myelosuppression grade 3 occurred as well as grade 1 nephro- and neurotoxicity. The maximum tolerated dose was 85 mg m-2 with dose limiting thrombocytopenia. Hypertonic saline was effective in preventing nephrotoxicity. Ondansetron was a very effective antiemetic in the first weeks of treatment but its efficacy waned later on. Responses were observed in head and neck cancer, melanoma and mesothelioma. At the dose level of 80 mg m-2 the optimal dose intensity was reached. This schedule will be tested further in phase II studies. 相似文献
23.
AS Leon 《Canadian Metallurgical Quarterly》1993,15(6):1094-1107
The antihypertensive effects and tolerability of single daily doses of enalapril and extended-release nifedipine (nifedipine-ER) were compared in an open-label, randomized, parallel-group, 22-week treatment study involving 230 men and women (mean age, 55 years). Following a 3-week washout period, mean +/- SD blood pressure levels were 153 +/- 17/99 +/- 4 mmHg in the enalapril group (n = 117) and 157 +/- 17/100 +/- 5 mmHg in the nifedipine-ER group (n = 113). Beginning at 5 mg once daily for enalapril and 30 mg once daily for nifedipine-ER, the dosage was titrated every 4 weeks for 16 weeks, up to a maximum of 40 mg for enalapril and 120 mg for nifedipine-ER. The treatment goal (satisfactory response) was to lower trough sitting diastolic blood pressure to < 90 mmHg or by at least 10 mmHg to a level of < 100 mmHg. At a mean daily dose of 16 mg of enalapril and 57 mg of nifedipine-ER, more than three quarters of each treatment group achieved a satisfactory response. The mean reductions in trough sitting blood pressure levels at the end of 22 weeks of treatment were 15/11 mmHg for enalapril and 21/13 mmHg for nifedipine-ER. The difference between treatments was significant only for the change in systolic blood pressure (P < 0.05). However, enalapril was better tolerated than nifedipine-ER. The numbers of patients with adverse experiences and withdrawals from the study because of an adverse experience were significantly lower for enalapril than for nifedipine-ER (P < 0.05). The incidence of abnormal laboratory findings was small and considered of no clinical importance in either group. These data suggest that enalapril and nifedipine-ER had approximately equal efficacy as once-daily antihypertensive treatments, but enalapril was better tolerated. 相似文献
24.
25.
H Everaert A Maes AS Hambye L Mesotten L Mortelmans PR Franken 《Canadian Metallurgical Quarterly》1998,26(3):164-9; quiz 172-3
OBJECTIVE: After reading Part III of this series of nuclear cardiology articles, the technologist should be able to: (a) compare and contrast radiopharmaceuticals used for myocardial perfusion imaging; (b) describe imaging protocols used for detecting coronary artery disease; and (c) describe imaging patterns seen following reconstruction of myocardial images. 相似文献
26.
Activation of auditory cortex during silent lipreading 总被引:1,自引:0,他引:1
GA Calvert ET Bullmore MJ Brammer R Campbell SC Williams PK McGuire PW Woodruff SD Iversen AS David 《Canadian Metallurgical Quarterly》1997,276(5312):593-596
Watching a speaker's lips during face-to-face conversation (lipreading) markedly improves speech perception, particularly in noisy conditions. With functional magnetic resonance imaging it was found that these linguistic visual cues are sufficient to activate auditory cortex in normal hearing individuals in the absence of auditory speech sounds. Two further experiments suggest that these auditory cortical areas are not engaged when an individual is viewing nonlinguistic facial movements but appear to be activated by silent meaningless speechlike movements (pseudospeech). This supports psycholinguistic evidence that seen speech influences the perception of heard speech at a prelexical stage. 相似文献
27.
28.
ShSh Eliava IuM Filatov OB Sazonova AIu Lubnin IN Rudnev AS Khe?reddin 《Canadian Metallurgical Quarterly》1996,41(4):3-6
Internal carotid aneurysms in the ophthalmic area presents a challenge in cerebrovascular neurosurgery. The study was undertaken to provide evidence for the application of intravascular aspiration during direct surgical interventions and to outline their variants used at the N. N. Burdenko Institute of Neurosurgery. The study included 4 (3 females and 1 male) patients with large and giant internal carotid aneurysms of parasphenoidal site who were treated at the Institute. Clipping of the aneurysmal neck was made by employing intravascular blood aspiration from the aneurysm. The technique proved to be effective in proximal monitoring the carotid artery at surgery. It substantially reduced aneurysmal blood flow and wall tension, thus favouring aneurysmal dissection to make clipping. 相似文献
29.
An anonymous questionnaire inquiry performed among 324 school teachers in the Randers area with the purpose of elucidating teachers' knowledge about asthma is presented. To a series of statements about asthma, the teachers should answer yes, no or don't know. A limited knowledge about asthma in children was found. The knowledge about medicamental treatment was particularly limited. Only 57 per cent knew that wheezing after physical exertion is a strong indicator of asthma. Only five per cent had received proper instruction. This latter group had a significantly better knowledge of medical treatment (p < 0.0001-0.05). It is recommended that instruction in children's diseases, especially asthma should be reintroduced in teachers' training colleges. 相似文献
30.
An overview of the most important older and newer results regarding the relationship between violent and criminal behavior on the one hand and schizophrenic illness on the other hand is presented. Four different methods are available to study this relationship: (i) study of the prevalence of mental illness in criminal/violent populations; (ii) study of criminality/violence rate in samples of psychiatric patients; (iii) study of criminality/violence in community samples comparing mental patients with non-patient community residents; and (iv) study of criminality/violence in birth cohorts prospectively. All these methods have been used; but samples composed of schizophrenic patients exclusively were only exceptionally studied. The results indicate that there is a modest but significant relationship between schizophrenia and violence and crime which persists even after controlling for demographic and socio-economic variables. The probability of schizophrenic patients to be criminal or violent depends on the acuity of their illness and is increased by their use of psychoactive substances. Generally, however, violent and criminal acts directly attributable to mental illness account only for a very small proportion of such acts in the society. 相似文献