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91.
We studied saccadic and smooth pursuit eye movements in 24 patients suffering from multiple sclerosis during disease worsening, before and after high-dose 6-methylprednisolone infusions. Quantitative evaluation of saccades was based on amplitude/duration and amplitude/peak velocity relationships, precision (i.e. the ratio of actual to desired saccade amplitude) and the latency, whereas smooth pursuit eye movements were studied using target velocity/performance index relationship. At basal recordings, 22/24 (91.7%) of the patients showed at lest one abnormality. Eleven of the 24 patients (45.8%) showed modification of one or several parameters: improvement in 6 patients, worsening in 2, coexistence of both trends in 3. Latency improvement was the only significant modification when patients were considered as a group. Neurophysiological modifications did not correspond to clinical changes.  相似文献   
92.
The Testes in Cadmium Intoxication: Morphological and vascular aspects   总被引:1,自引:0,他引:1  
M. A. Gouveia 《Andrologia》1988,20(3):225-231
Cadmium toxicity was tested on young male Wistar rats by injecting 1 mg/ml of cadmium chloride (CdCl2) intra-peritoneally. Post-mortem examination was done 4 hours, 24 hours and 14 days after cadmium administration to observe time-sequence cadmium-induced alterations in vascular permeability of the mesothelium in the pleura, peritoneum and tunica vaginals. This paper mainly reports the alterations observed in the testes. Vascular permeability was assessed by the colloidal carbon technique. Vascular labelling was evidenced as early as 4 hours after CdCl2, injection; 24 hours later severe oedema with leakage of particles to the interstitium and also into the tubules was patent. Fourteen days after CdCl2 administration atrophy of the testes with necrosis of the tubules, fibrosis of the interstitium and vascular thrombosis was found, compatible with chemical castration.  相似文献   
93.
Plasma nicotine concentrations following administration by two types of nasal nicotine spray were compared in ten subjects. Absorption was particularly rapid during the first 2.5 min, the average rise in blood nicotine concentrations during this time being 8.6 ng/ml for the two products, followed by a small further rise to an average peak increase of 10.5 ng/ml 5 min after the dose of 2 mg nicotine base (mean 27.8 micrograms/kg). Despite a four-fold Cmax variation between subjects, the levels of individual subjects were fairly consistent across the two products. There were no significant differences between the two products in blood nicotine concentrations or cardiovascular responses, and the correlation between the AUCs from the two products was 0.68 (P = 0.01). Eight subjects reported subjective feelings of light-headedness or slight dizziness, which are not typical after slower absorption from nicotine gum or skin patches. Blood nicotine levels within the smoking range were soon built up with repeated doses, even in the subject with the least efficient nasal absorption. In a second study of ad libitum use under clinical conditions both products appeared sufficiently acceptable for therapeutic use as an aid to smoking cessation. There was no tendency to escalate to excessive use over 4 weeks, and blood nicotine concentrations in nine subjects averaged only 44% of their prior smoking levels. Only one subject had levels equivalent to prior smoking and possible reasons why this was not more common are discussed.  相似文献   
94.
米非司酮作用于兔输卵管收缩活动与Ca^2+关系的研究   总被引:1,自引:0,他引:1  
通过“结合化学分离与原子吸收分光光度法”对Ca^2 含量测定和离体输卵管肌条收缩记录方法,研究米非司酮(Ru486)对增加假孕(4d)兔输卵管平滑肌收缩频率,而不改变其收缩张力和振幅时与Ca^2 之间的关系,结果提示:(1)Ru486对输卵管分泌液和组织内Ca^2 的含量分布无明显影响;(2)Ru486具有降低细胞外液高Ca^2 浓度促Ca^2 内流,而使收缩增强的效应,且能协同Ca^2 通道阻断剂(Verapamil)抑制细胞外Ca^2 内流,而致收缩减弱的效应。  相似文献   
95.
The antimicrobial effects of a saturated calcium hydroxide solution, and in combination with 10% and 20% detergent, were evaluated on Streptococcus faecalis. Strepto-coccus sanguis, Streptococcus mutans, Streptococcus salivarius, Neisseria sp., diphlheroid, Staphylococcus aureus, Lactobacillus sp., Staphylococcus epidermidis, Bacillus suhtilis and Candida albicans. The saturated calcium hydroxide solution was effective against only four of the 11 microorganisms studied over a 60-min exposure time. The calcium hydroxide solutions con-taining detergent killed all 11 test organisms over a 30-min exposure time. This difference was statistically significant (P<0.01). No statistically significant difference in antimicrobial action was found between the 10% and 20% detergent calcium hydroxide solutions (F>0.01). However, the low surface tension (46.5 × 10?3 Nm?1) and high pH (10.8) of the calcium hydroxide solution with 20% detergent establish it as the more effective solution.  相似文献   
96.
Analogs of Neuropeptide Y (NPY) were synthesized with conventional Boc/benzyl protective group strategy. Instead of Asn7 in the native scquence, Boc-Lys(Alloc)-OH was incorporated. At the end of the synthesis the Alloc group was selectively removed by palladium-catalyzed hydrostannolysis and biotin coupled to the e-amino group of Lys7. After cleavage and characterization with plasma desorption mass spectrometry the Ne-7-biotinyl-[Lys7]-NPY and the nonbiotinylated analog [Lys7]-NPY were investigated as ligands to the NPY receptor from rat cerebral cortex. Both analogs were found to be high affinity ligands to the NPY receptor and bound with essentially the same affinity as unmodified NPY.  相似文献   
97.
Summary In an open, randomized, comparative, between-patient trial, 45 postmenopausal women were treated for 4 months with cyclical transdermal oestradiol 0.05 mg per day or oral conjugated equine oestrogens 0.625 mg per day, in both cases, plus, medroxyprogesterone acetate 10 mg per day on the last 8 days of each cycle. Similar relief from postmenopausal symptoms was obtained with both treatments. Post-treatment histological evaluation of the endometrium did not reveal neoplastic or hyperplastic change in any patient.Early follicular-phase plasma oestradiol levels were observed only after transdermal oestradiol. There was a significant reduction in serum total cholesterol and LDL cholesterol in both treatment groups, with no difference between treatments, whereas serum triglyceride levels were decreased only by transdermal oestradiol. Plasma calcium and phosphorus fell significantly and serum intact parathyroid hormone rose significantly, with no difference between the therapies. No significant changes were observed in clotting factors.Transdermal oestradiol appears to be an effective and safe hormonal replacement therapy, and this route of administration may be responsible for the more useful action of the drug on serum lipids and plasma oestradiol levels.  相似文献   
98.
Pulsed Nd-YAG laser irradiation of bacteria has been suggested as a possible means of treating contaminated intra-oral sites although relatively few studies have been conducted. In this investigation, the antimicrobial activity of a pulsed Nd-YAG laser was assessed in vitro for a range of oral bacteria using several pulse energies and exposure durations. Pure cultures of each organism were lased in saline suspensions followed by standard colony counting techniques for test and control samples. Microbial inhibition was found to be organism-dependent and varied with energy dose and pulse energy. For all nine test species 120-mJ laser pulses proved more efficient than 80-mJ pulses, with 99.9% kills compared with around 90% kills after exposure to 1800 pulses. These killing activity levels compare favourably with those achieved with other lasers in vitro.  相似文献   
99.
本实验采用静脉注射肾上腺素造成大鼠肺损伤模型,观察消炎痛对肾上腺素性肺损伤时,肺血管壁通透性及肺组织形态学影响。结果表明:消炎痛可预防肾上腺素所致的肺血管壁、肺泡壁通透性增高(分别为P<0.025;P<0.01),延长存活时间(P<0.001);形态学检查:肺损伤明显减轻(P<0.005)。提示前列腺素(PG)参与了肾上腺素性肺损伤。  相似文献   
100.
目的研究在化疗过程中运用扶正调平汤对减轻肿瘤患者的骨髓抑制,消化道症状等化疗副反应的作用。方法通过临床对60例手术及非手术胃癌患者随机分成两组,即治疗组和对照组,观察化疗前后两组的血象变化、消化道反应情况,及其生活质量进行评定,比较、分析。结果实验证明化疗同时配合扶正调平汤对改善化疗副反应的作用显著化于对照组(P〈0.05)。结论说明扶正调平汤对减轻化疗毒副反应方面具有较好的临床疗效。提高了患者生活质量,使惠者顺利完成化疗疗程。  相似文献   
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