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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
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994.
S P Newman G Woodman F Morén S W Clarke 《British journal of diseases of the chest》1988,82(3):262-267
Metered dose inhalers are sometimes used in conjunction with NebuhalerR, a 750 ml holding chamber, but the permissible delay time between actuating the aerosol into Nebuhaler and commencing inhalation is unknown. We have compared in 10 asthmatic patients the bronchodilator responses following inhalations of terbutaline sulphate from Nebuhaler after delays of 1, 5 and 30 seconds and following placebo inhalation. Terbutaline sulphate was administered as 2 puffs, each of 250 micrograms, separated by approximately 15 minutes. After each delay time, terbutaline produced increases in forced expiratory volume in one second (FEV1), peak expiratory flow rate (PEFR) and maximum expiratory flow following exhalation of 75% of the forced vital capacity (V max25) significantly greater than those after placebo (P less than 0.01). Changes in PEFR did not vary significantly among the three delay times, but the increases in FEV1 and in V max25 were significantly reduced with 30 seconds' delay. It is concluded that the delay between actuation into Nebuhaler and commencing inhalation can be extended from 1 second to 5 seconds without significant loss of drug efficacy, and that further extension to 30 seconds causes only a small loss of bronchodilatation: hence the delay time is unlikely to be of major importance in clinical practice. 相似文献
995.
We describe an infertile man with normal secondary sexual characteristics and a 45X karyotype. Physical examination showed bilateral soft small testes and the semen contained no sperm. Serum testosterone, estrogen and gonadotropin levels were within normal range. Biopsy of the testis showed germinal aplasia. 相似文献
996.
The pharmacological properties of the imidazobenzodiazepine, FG 8205, a novel partial agonist at the benzodiazepine receptor 总被引:2,自引:1,他引:1
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M D Tricklebank T Honoré S D Iversen J A Kemp A R Knight G R Marshall N M Rupniak L Singh S Tye F Watjen 《British journal of pharmacology》1990,101(3):753-761
1. The pharmacological properties of the benzodiazepine receptor ligand, FG 8205 (7-chloro-5,6-dihydro-5-methyl-6-oxo-3-(5-isopropyl-1,2,4-oxadiazol++ +-3-yl)-4H- imidazol[1,5a][1,4]benzodiazepine) have been examined. 2. FG 8205 potently displaced [3H]-flumazenil binding in rat cortical membranes with a Ki of 3.3 nM, but was inactive at 13 neurotransmitter recognition sites. 3. Consistent with a partial agonist profile, the affinity of FG 8205 for the benzodiazepine recognition site was increased in the presence of gamma-aminobutyric acid (GABA, 300 microM) by a degree (-log [IC50 in the presence of GABA/IC50 alone] = 0.34) significantly less than found for diazepam (0.46). FG 8205 also potentiated the inhibitory potency of the GABAA-receptor agonist, isoguvacine, on the hippocampal CA1 population spike and, again, the maximum shift (-log dose-ratio = 0.2) was significantly less than that seen with diazepam (0.4). 4. In anticonvulsant studies, the ED50 doses of FG 8205 and diazepam needed to antagonize seizures induced by pentylenetetrazol (PTZ) or by sound in audiogenic seizure prone mice were similar with values of 0.2-0.3 mg kg-1, i.p. However, even high doses of FG 8205 (50 mg kg-1) did not protect against seizures induced by electroshock. 5. FG 8205 released responding suppressed by footshock in a rat operant conditioned emotional response task over the dose range 0.5-50 mg kg-1 (i.p.). Similar doses of FG 8205 had a marked taming effect in cynomolgus monkeys.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
997.
Isolation and characterization of motile Aeromonas from human, food and environmental specimens 总被引:8,自引:0,他引:8
From July 1985 to March 1987, the occurrence of motile Aeromonas sp. in stool, food and environmental specimens was investigated to assess their pathogenic significance and to determine sources and routes of infection. A total of 9366 stool specimens were examined; Aeromonas was isolated from 11.1% of diarrhoeal stools and 2.2% of normal stools (P less than 0.001). Aeromonas counts in food specimens, which included minced beef, pork and chicken, seafood and various vegetables and their products, were unexpectedly high suggesting that infection might be food-borne rather than water-borne. About 70% of the isolates from meat products were A. hydrophila and A. sobria, while A. caviae was the most common in sea-fish, vegetables and their products. Most A. hydrophila and A. sobria strains produced haemolysin, but haemagglutinin was found more frequently in A. sobria. 相似文献
998.
Epinephrine (1, 3 and 10 micrograms/kg) was found to increase retinal and choroidal blood flow (22, 49 and 67%) when it was administered intravenously. The increase in retinal and choroidal blood flow coincided well with the increase in systemic blood pressure (44, 65 and 96%, respectively). When epinephrine (2%) was instilled to the eyes topically the retinal and choroidal blood flow decreased (15%) while systemic blood pressure remained unchanged. It is suggested that the decrease in retinal and choroidal blood flow by topical epinephrine could be the cause of epinephrine maculopathy reported previously. L-Timolol (0.25%, topically) did not affect retinal and choroidal blood flow significantly. 相似文献
999.
L Z Wu L H Zeng Q Y Ma Y J Xie Y Z Chen D Z Wu 《Japanese journal of ophthalmology》1988,32(2):236-245
The hereditary characteristics of enzyme deficiency and dermatoglyphics in congenital color blindness (CCB) were studied. We propose that there is a linkage between the two loci on the X-chromosome determining CCB and glucose-6-phosphate dehydrogenase (G6PD), based on our study of a high incidence of G6PD deficiency in 156 male cases with CCB. The CCB gene is closely linked with that of G6PD deficiency from our pedigree investigations. The rise in the frequency of eight or more whorls, the low value of atd angle and the presenting rate of real palmar patterns of the thenar, hypothenar and I, areas presented the hereditary traits of congenital color blindness. 相似文献
1000.
Epithelial cyst in the anterior chamber after penetrating keratoplasty: a rare complication. 总被引:1,自引:0,他引:1
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We report the case of a 25-year-old man who had a penetrating keratoplasty for keratoconus. A year and a half after surgery a cyst was noted in the anterior chamber, which was observed to enlarge over six months. Because of anxiety about endothelial touch, it was removed surgically. Histologically the cyst was composed of stratified, non-keratinized squamous epithelium attached to loose fibrovascular tissue including islands of melanin-containing epithelial cells. This was interpreted as an epithelial implantation cyst of the anterior chamber of corneal origin attached to iris tissue. 相似文献