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71.
AT Cruchley DM Williams PM Farthing PM Speight CA Lesch CA Squier 《Canadian Metallurgical Quarterly》1994,23(2):55-59
Hyperthyroidism is a common endocrinologic disorder affecting many organ systems. Musculoskeletal and neurological involvement present themselves as fatigue, muscle weakness and paralysis. Electromyography (EMG) is essential for differential diagnosis of muscle weakness. Well defined neuropathy and myopathy have been described in these patients. In the present study 17 hyperthyroid patients were evaluated with electrophysiological tests in addition to physical and neurological examinations and biochemical laboratory studies. Needle EMG, motor and sensory conduction velocities, median and tibial somatosensory evoked potentials (SEP) were studied. For assessment of the activity of disease clinical status, neurological symptom and disability scores and serum T3, T4 and TSH levels were examined. Statistical analysis of neuroelectrophysiological findings of the patient and the control groups yielded meaningful difference in the needle EMG, sensory conduction velocity and evoked potential findings. Abnormalities were observed in 80% of the proximal muscles besides polyphasic potentials that were seen in 20% of the extensor digitorum brevis muscle. Median, ulnar and sural nerve sensory action potential amplitudes were found to be lower than that of the control group. Sural sensory nerve conduction velocity of patients was decreased in 35.5%, prolongation of median SEP latencies and increase in the amplitudes were not however statistically significant. Prolongation of Tibial SEP N1, P2 latencies were seen in 47%, amplitudes of N1 were increased in 88.2%, P2 in 58.8%, N2 in 47%. The thyroid clinical status score was correlated with Tibial SEPs amplitude. These findings suggest the presence of an initial axonal type of mild polyneuropathy. As a conclusion electrophysiological studies can be useful in the diagnosis of asymptomatic polyneuropathy in hyperthyroid patients. 相似文献
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L Kabasakal BD Collier R Shaker RS Hellman S Smart K Ozker AZ Krasnow AT Isitman 《Canadian Metallurgical Quarterly》1996,37(8):1285-1288
Twenty-six patients with squamous cell cancer of the cervix were treated with i.v. paclitaxel, 250 mg/m2 over 3 h every 21 days. They received steroid, H1 and H2 blocker premedications, and granulocyte-colony-stimulating factor (G-CSF) support (5 microgram/kg/day). No prior chemotherapy, except as a radiation sensitizer, was allowed. The median age was 50 (range, 36-81) years, and performance status Zubrod was 1 (range, 0-2). Eight (33%) patients had prior surgery, and 22 (92%) had prior radiation therapy. Twenty-four patients were evaluable for response; 2 were later found to be ineligible. Five patients had partial responses (21%; 95% confidence interval, 6-40%), and 14 (58%; 95% confidence interval, 35-78%) had stable disease. The median duration of response was 10 (range, 3-27+) weeks. The responses were within the radiation port (four responses) and outside of it (one response). The median interval from the start of irradiation to the start of paclitaxel in responding patients was 94 weeks, whereas in patients with stable disease it was 68 weeks, and in patients whose disease progressed it was 46 weeks. Eighty-eight percent of the 105 cycles of paclitaxel were administered at a dose of 250 mg/m2 or higher. Granulocytopenia was brief and noncumulative, with grades 3 and 4 experienced by 5 and 3 patients, respectively. G-CSF was used for a median of 7 (range, 2-14) days/cycle. Anemia was mild, with G3 noted in 3 patients, and thrombocytopenia was not significant. Infections and musculoskeletal pain were mild and infrequent. Sensory (14 patients G1 or G2 and 2 patients G3) and motor (4 patients G1 or G2 and 1 patient G3) neurotoxicity was noted. There was no significant cardiovascular toxicity. Paclitaxel is active in patients with squamous cell cancer of the cervix and is well tolerated at this dose schedule with G-CSF support. 相似文献
75.
In male Syrian hamsters, short days induce regression of the reproductive system, but eventually spontaneous recrudescence occurs ensuing from refractoriness to the inhibitory photoperiod. Although the photoperiod of 12 L:12 D (12 h light:12 h dark) may act like a short day by inducing the testicular cycle outlined above, it may fail to evoke the increase of circulating concentrations of prolactin that accompanies testicular recrudescence. This photoperiod may fail to induce photorefractoriness, as indicated by the prolonged low concentrations of prolactin in the blood. Herein, hamsters were exposed to either 8 L:16 D or 12 L:12 D from weaning and by 28 weeks exposure to either photoperiod, the hamsters had large testes following recrudescence from a photoperiod induced-regression). Transfer to 8 L:16 D from 12 L:12 D at 28 weeks resulted in a second testicular regression and recrudescence. In a second experiment, the testes of hamsters moved to 8 L:16 D from 12 L:12 D after 29 weeks exposure to the latter photoperiod similarly regressed and then regrew. Serum concentrations of prolactin decreased in these males after transfer to the shorter daylength but also decreased in hamsters kept under 12 L:12 D both groups were usually below those of hamsters moved to 14 L:10 D. These results show that exposure for 28 or 29 weeks to 12 L:12 D was insufficient to induce photorefractoriness, despite the recrudescence of the testes following involution. 相似文献
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Fundus reflection densitometry or retinal densitometry is a non-invasive technique to examine the visual photopigment kinetics in living eyes. The technique is based on the comparison of the reflected light from the fundus in a fully light adapted eye (when all visual photopigment has been bleached) with the reflected light following complete dark adaptation (when the retina contains its maximum amount of visual photopigment). The technique provides a measure of the density of visual photopigment, its time constant of regeneration, its distribution and spectral characteristics if measured at a series of wavelengths. Fundus reflection densitometry in the human eye was introduced 40 years ago. Presently, it is the only available technique from which direct and objective insight can be obtained into visual photopigment. This knowledge is particularly relevant in eyes where abnormalities of photoreceptor function are suspected. This paper summarizes the current knowledge of fundus reflection densitometry in the diseased and in the aging human retina, gathered over the last 30 years. Considerable improvements of the instrument for clinical purposes have been obtained, and are also discussed. 相似文献
79.
The cross-cultural generalizability of personality dimensions was investigated by (a) identifying indigenous Philippine dimensions, (b) testing the cross-cultural replicability of the NEO 5-factor model (P. T. Costa & R.R. McCrae, 1992), and (c) relating Philippine and Western dimensions in Philippine and U.S. samples of college students. Filipino self-ratings (N = 536) on indigenous items were factor analyzed, and 6 Philippine dimensions were obtained. Conclusions about the replicability of the 5-factor model in the Philippines (N = 432) depended on whether exploratory, Procrustes, or confirmatory factor methods were used. In regression and joint factor analyses, moderate to strong associations were found between the Philippine dimensions and (a) dimensions from the 5-factor model in both Philippine (N = 387) and U.S. (N = 610) samples, and (b) the Tellegen model (A. Tellegen, 1985; A. Tellegen & N.G. Waller, in press) in a U.S. sample (N = 603). 相似文献
80.
RA Blackwood AT Transue DM Harsh RC Brower SJ Zacharek JE Smolen RJ Hessler 《Canadian Metallurgical Quarterly》1996,59(5):663-670
Neutrophil stimulation results in the activation of a variety of phospholipases, including phospholipase A2 (PLA2), which releases arachidonic acid from the 2 position of membrane phospholipids, leaving a lysophospholipid. Because arachidonic acid is known to be a potent fusogen in vitro, we examined the effect of metabolism by PLA2 on the fusion of complex liposomes (liposomes prepared with a phospholipid composition similar to that found in neutrophil plasma membrane). We observed that PLA2 augmented the fusion of complex liposomes with each other as well as with specific granules isolated from human neutrophils, lowering the Ca2+ requirement for fusion by three orders of magnitude. Furthermore, although lysophospholipids inhibited fusion, the incorporation of arachidonic acid into liposome membranes overcame the inhibitory effects of the lysophospholipids. Thus with PLA2 and annexins we were able to obtain fusion of complex liposomes at concentrations of Ca2+ that are close to physiological. Our data suggest that the activation of PLA2 and the generation of arachidonic acid may be the major fusion-promoting event mediating neutrophil degranulation. 相似文献