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41.
HD Connor RG Thurman G Chen JL Poyer EG Janzen RP Mason 《Canadian Metallurgical Quarterly》1998,24(9):1364-1368
It has been proposed that the C-phenyl-N-tert-butylnitrone/trichloromethyl radical adduct (PBN/.CCl3) is metabolized to either the C-phenyl-N-tert-butylnitrone/carbon dioxide anion radical adduct (PBN/.CO2-) or the glutathione (GSH) and CCl4-dependent PBN radical adduct (PBN/[GSH-.CCl3]). Inclusion of PBN/.CCl3 in microsomal incubations containing GSH, nicotinamide adenine dinucleotide phosphate (NADPH), or GSH plus NADPH produced no electron spin resonance (ESR) spectral data indicative of the formation of either the PBN/[GSH-.CCl3] or PBN/.CO2- radical adducts. Microsomes alone or with GSH had no effect on the PBN/.CCl3 radical adduct. Addition of NADPH to a microsomal system containing PBN/.CCl3 presumably reduced the radical adduct to its ESR-silent hydroxylamine because no ESR signal was observed. The Folch extract of this system produced an ESR spectrum that was a composite of two radicals, one of which had hyperfine coupling constants identical to those of PBN/.CCl3. We conclude that PBN/.CCl3 is not metabolized into either PBN/[GSH-.CCl3] or PBN/.CO2- in microsomal systems. 相似文献
42.
ET Rolls HD Critchley AS Browning I Hernadi L Lenard 《Canadian Metallurgical Quarterly》1999,19(4):1532-1540
The primate orbitofrontal cortex is a site of convergence of information from primary taste, olfactory, and somatosensory cortical areas. We describe the responses of a population of single neurons in the orbitofrontal cortex that responds to fat in the mouth. The neurons respond, when fatty foods are being eaten, to pure fat such as glyceryl trioleate and also to substances with a similar texture but different chemical composition such as paraffin oil (hydrocarbon) and silicone oil [Si(CH3)2O)n]. This is evidence that the neurons respond to the oral texture of fat, sensed by the somatosensory system. Some of the population of neurons respond unimodally to the texture of fat. Other single neurons show convergence of taste inputs, and others of olfactory inputs, onto single neurons that respond to fat. For example, neurons were found that responded to the mouth feel of fat and the taste of monosodium glutamate (both found in milk), or to the mouth feel of fat and to odor. Feeding to satiety reduces the responses of these neurons to the fatty food eaten, but the neurons still respond to some other foods that have not been fed to satiety. Thus sensory-specific satiety for fat is represented in the responses of single neurons in the primate orbitofrontal cortex. Fat is an important constituent of food that affects its palatability and nutritional effects. The findings described provide evidence that the reward value (or pleasantness) of the mouth feel of fat is represented in the primate orbitofrontal cortex and that the representation is relevant to appetite. 相似文献
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M van der Gaag AJ Debets HD Osiewacz RF Hoekstra 《Canadian Metallurgical Quarterly》1998,258(5):521-529
We have investigated the properties of the newly synthesized proton-pump inhibitor, 3-butyryl-8-methoxy-4-[(2-thiophenyl)amino]quinoline (YJA20379-6), on gastric mucosal proton-pump (H+/K+-ATPase) activity, gastric acid secretion and gastroduodenal lesions in experimental rats. YJA20379-6 markedly inhibited H+/K+-ATPase activity in rabbit isolated gastric mucosal microsomes, confirming its classification as a proton-pump inhibitor. The inhibitory efficacy of YJA20379-6 on the proton pump was approximately 14-times higher than that of omeprazole at pH 7.4. YJA20379-6 given intraduodenally had a potent inhibitory effect on gastric secretion in pylorus-ligated rats (ED50 22.9 mg kg(-1)) but was less active than omeprazole. Pretreatment of rats with YJA20379-6 dose-dependently protected the gastric mucosa from damage induced by water-immersion stress, indomethacin and absolute ethanol, and the duodenal mucosa from damage induced by mepirizole. Repeated administration of YJA20379-6 also dose-dependently accelerated the spontaneous healing of acetic acid-induced gastric ulcers. These results suggest that YJA20379-6 has potent anti-secretory and anti-ulcer effects which are exerted by suppression of H+/K+-ATPase activity in gastric parietal cells. YJA20379-6 might be useful for the clinical treatment of peptic ulcer diseases. 相似文献
45.
Transcutaneous lower blepharoplasty as a standard procedure for cosmetic lower blepharoplasty is being replaced by transconjunctival blepharoplasty and laser resurfacing techniques. Nevertheless, there remain specific indications for the transcutaneous approach and its modifications. The accomplished facial plastic surgeon will be able to choose the appropriate technique based on the patient's concerns, the eyelid pathology, and his or her clinical experience. 相似文献
46.
MF Nitschke UH Melchert C Hahn V Otto H Arnold HD Herrmann G Nowak M Westphal K Wessel 《Canadian Metallurgical Quarterly》1998,140(12):1223-1229
Intracranial lesions may compromise structures critical for motor performance, and mapping of the cortex, especially of the motor hand area, is important to reduce postoperative morbidity. We investigated nine patients with parietal lobe tumours and used functional MRI sensitized to changes in blood oxygenation to define the different motor areas, especially the primary sensorimotor cortex, in relation to the localization of the tumour. Activation was determined by pixel-by-pixel correlation of the signal intensity time course with a reference waveform equivalent to the stimulus protocol. All subjects showed significant activation of the primary sensorimotor cortex while performing a finger opposition task with the affected and unaffected side. In five patients the finger opposition task additionally activated the ipsilateral sensorimotor cortex and the supplementary motor area (SMA). Extension and flexion of the foot, additionally performed in two patients, also activated the sensorimotor cortex, in one case within the perifocal oedema of the tumour. Tumour localization near the central sulcus induced displacement of the sensorimotor cortex as compared to the unaffected side in all patients with a relevant mass effect. The results of our study demonstrate that functional MRI at 1.5 T with a clinically used tomograph can reproducibly localize critical brain regions in patients with intracranial lesions. 相似文献
47.
HD Vuyk 《Canadian Metallurgical Quarterly》1997,111(5):424-430
Prominent ears are the most frequent congenital deformity in the head and neck region. Anatomy of normal and prominent ears as well as the psychological aspects of prominent ears are reviewed. Two types of surgical technique are described with emphasis on the cartilage-sparing technique. A sound pre-operative analysis, focusing on all parts of the deformity, and surgical techniques which are gradually applied to these deformities should result in pleasing, permanent changes for the vast majority of patients. In our opinion, a combination of cartilage-sparing techniques augmented with cartilage-weakening procedures give predictable long-term results with a natural appearing ear and concomitant few, easily treated complications. 相似文献
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HD McIntosh 《Canadian Metallurgical Quarterly》1996,19(11):846-856
The announcement of the National Heart Attack Alert Program by the National Heart, Lung and Blood Institute in June of 1991 prompted leaders of the Florida Chapter of the American College of Cardiology to develop a statewide program to reduce the morbidity and mortality from acute myocardial infarctions within Florida. It became apparent that the success of such a program would require the prompt institution of thrombolytic agent or other revascularization procedures in appropriate patients. No longer could the decision regarding institution of therapy await discussion by telephone and/or the arrival at the emergency department (ED) of the patient's primary care physician or cardiologist. Efforts to establish appropriate protocols for therapy revealed that many of the 25,000 or more physicians currently staffing the 5,600 or so EDs in this country were moonlighting residents or practitioners from a variety of specialties or subspecialties with limited or no formal EM training. Furthermore, it was learned that there were in the entire country only about 800 postgraduate, year-one Council for Graduate Medical Education accredited training positions. There were only 21 such training positions in the entire state of Florida. The reasons for these deficiencies are discussed and a challenge to correct this person power crisis is issued, not principally to the leadership of EM, but to the entire medical profession. 相似文献