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71.
Lei Li Christine Eng Robert J. Desnick James German Nathan A. Ellis 《Molecular genetics and metabolism》1998,64(4):286-290
Bloom syndrome is more common in individuals of Ashkenazi Jewish descent than in any other population, and one particular mutation in the Bloom syndrome gene,blmAsh,is homozygous in nearly all Ashkenazi Jewish persons with Bloom syndrome. We have determined the frequency ofblmAshin 1491 Ashkenazi Jewish persons with no known history of Bloom syndrome and found that 1 in 107 persons was heterozygous. Although not common, genetic screening for Bloom syndrome is feasible in this population. 相似文献
72.
M. N. Karpova I. Yu. Abrosimov G. N. Kryzhanovskii 《Bulletin of experimental biology and medicine》1998,126(1):667-669
The pharmacological kindling with corazol was used as a model of chronic cerebral epileptization. In contrast to sham-operated
rats or rats with unilateral occlusion of the common carotid arteries, bilateral occlusion of these vessels moderated acute
seizures provoked by a single administration of the convulsant corazol and abated the enhanced cerebral seizure readiness
induced by its repeated administration.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 7, pp. 30–33, July, 1998 相似文献
73.
Separate detectors for simple and complex grating patterns? 总被引:1,自引:0,他引:1
Grating having two sinusoidal components show a periodic variation in contrast which is visible as a "beat" pattern. The spatial frequency of the beat is the difference between the frequencies of the two components. Thresholds for a number of detection and discrimination tasks were measured using beat patterns of 1 c/deg (with components of 9 and 10 c/deg), and gratings of 1 and 10 c/deg. Temporal modulation at 6 Hz lowered detection thresholds for 1 c/deg gratings, but not for beats or 10 c/deg gratings. The effect of contrast on the range of temporal frequencies over which direction of movement can be discriminated differs for the three types of pattern: beats resemble neither low nor high spatial frequency gratings. Low and (for 2 of 3 observers) high spatial frequency gratings, but not beat patterns, are susceptible to a movement after effect induced by a low spatial-frequency grating. Beat patterns induce little or no movement after effect. We conclude that beat patterns are not detected by the same mechanisms that detect simple gratings. 相似文献
74.
The study of in vivo occupancy of benzodiazepine receptors in rat hippocampus and cerebellum indicates that premazepam reaches only about 70% and 80% occupancy respectively within the dose range used for pharmacological tests in rats. Moreover, at equiactive doses (antileptazol ED50), more brain receptors are occupied by premazepam than by other benzodiazepines, suggesting that premazepam may act as a partial agonist at benzodiazepine receptors, with intrinsic activity lower in cerebellum than in hippocampus. These results may explain the lack of sedative and ataxic properties of premazepam. 相似文献
75.
胡萝卜籽挥发油的抗生育作用 总被引:3,自引:0,他引:3
胡萝卜籽挥发油对小鼠有抗着床,抗早、中和晚期妊娠作用。对大鼠也有抗着床作用。挥发油中的萜类碳氢化合物部位,对小鼠皮下注射抗早期妊娠的ED_(50)为2.9ml/kg,甲地孕酮和hCG能明显逆转其作用;对假孕小鼠蜕膜瘤有抑制作用,此作用不能被甲地孕酮拮抗,皮下注射于早孕大鼠24、48小时后血浆孕酮浓度明显下降。以上提示其抗早孕作用机制可能与抑制孕酮合成和蜕膜反应有关。此外,挥发油碳氢部分无雌激素和抗雌激素活性,低浓度时对早孕大鼠离体子宫的收缩活动没有影响,高浓度则表现抑制作用。 相似文献
76.
Summary In blood of 21 anemic patients and 8 normal subjects (N) thre oxygen dissociation curves each were measured at different pH values to calculate Bohr coefficients after acidification with CO2 (BCCO
2) or fixed acid (BCFA), and other important parameters of oxygen affinity. The patients had either low hemoglobin or red cell production (L:n=11, 7.3 g/dl Hb) or high erythrocyte production combined with high loss (H:n=10, 7.8 g/dl Hb). The standard half saturation pressure P50 (pH 7.4, 37°C) was equally elevated in both anemic groups (L:30.5, H:30.8, N:26.7 mmHg), as well as the diphosphoglycerate concentration (DPG) (L:18.7, H:18.6, N:12.7 mol/g Hb). The red cell pH of the anemics was lower than for the N (approximately 0.045 units) causing part of the difference in P50. Hill's ntended to high values in the anemics except at low O2-saturation in the H. For BCCO
2 no significant difference among the groups was observed. BCFA, however, increased in the H at low SO
2 compared to the N and L. The cause for most of the changes in hemoglobin oxygen affinity in anemics was the high [DPG]. The combination of high P50 and high n value as in the L seems to be most advantageous for tissue oxygenation.The measurements were performed during a stay as visiting professor at the Universidad del Valle, supported by Deutscher Akademischer Austauschdienst VS 931 509 0013 相似文献
77.
孙佑勤 《青岛大学医学院学报》1986,(1)
本文报道用银屑灵治疗银屑病351例,疗程60天,对有效病例延长疗程可提高治愈率.临床痊愈率32.2%,总有效率73.8%,点滴状银屑病疗效最好.随访2年,复发率19.5%.仅少数病例有轻微胃肠道反应,但有6例治疗前发现肝功能异常,作者认为可能属银屑病的肝脏损害,经治疗后转正常.并对治疗机理作了初步探讨. 相似文献
78.
Summary The SUR 2647 combination is a sachet formulation containing free paracetamol and its N-acetyl-methionate ester (SUR 2647). In a randomized, single-blind, between-patient study the onset of analgesia, duration and efficacy of the SUR 2647 combination vs paracetamol was investigated in outpatients after oral surgery. One group (n=27) received sachets of SUR 2647 combination 2 b.i.d. (equivalent to 2 g paracetamol ×2) on the day of operation, and one sachet b.i.d. (equivalent to 1 g paracetamol ×2) for the following two days. The other group (n=26) received paracetamol tablets 2 q.i.d. on the day of operation (1 g×4) and one tablet q.i.d. (0.5 g×4) for the following two days. Several objective and subjective assessments, including pain score on a visual analogue scale, were recorded for comparison of the postoperative courses. Median onset of analgesia for both groups was 0.5 h. The duration after SUR 2647 combination was 5.5 h as compared to 2.5 h for paracetamol. Mean pain scores showed that the SUR 2647 combination regime reduced pain significantly more than the paracetamol regime from 0.5 to 3.0 h after initiation of medication. The mean pain scores did not show a significant difference during the remaining observation period. Mild to moderate drowsiness was reported in both treatment groups, but it was more common in subjects given SUR 2647 combination. 相似文献
79.
Colored neon flanks and line gap enhancement 总被引:1,自引:0,他引:1
When a colored line connects two black (or differently colored) lines across a gap, colored neon flanks are seen on either side of it. These flanks extend over gap sizes of 50 min arc foveally and are not explained by Bezold-type assimilation. They may be elicited by black lines as short as 6 min arc adjoining the colored line at each end. To maximize these flanks, the black and colored lines must appear linearly continuous. Nonaligned junctions weaken the effect and an angular tilt of more than 40 dog destroys it. In this and other respects, (local) neon flanks are similar to van Tuijl's (global) neon color spreading (1975). Both phenomena have analogs in brightness perception. We propose that neon spreading is a lateral extension of neon flanks across the empty space between them, and discuss similarities of these effects with other brightness illusions (Schumann, Prandtl, Ehrenstein). For this group of illusions the term "line gap enhancement" is introduced to imply perceptual enhancement of changes in brightness and/or color along lines. Correspondences between the psychophysical properties and structural prerequisites for line gap enhancement on one hand and neuronal response properties of end-zone inhibited (hypercomplex) cortical cells on the other are discussed. 相似文献
80.
糖尿病足溃疡是糖尿病严重的破坏性并发症,致残率及致死率逐年增高,严重威胁人类身心健康。中医药治疗糖尿病足溃疡,注重辨证论治与整体观念相结合,不仅能改善中医证候,更能在加速创面愈合的同时减少创面的复发,一定程度上延缓了糖尿病足溃疡的进一步恶化,降低其致残率及致死率。现代研究发现,糖尿病足溃疡难以愈合与各种细胞因子如炎症因子、生长因子、趋化因子等分布异常密切相关;随着现代医学对中医药研究的不断深入,中药单体及复方调控细胞因子治疗糖尿病足溃疡已成为研究热点,该文通过对目前国内外研究现状进行归纳,得出以下总结:(1)芝麻酚、栀子苷、当归补血汤、紫朱软膏等调节肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-1、IL-6、IL-10等炎症因子,抑制创面炎症。(2)白芷、丹酚酸B、四效散、壮药拔毒生肌膏等调节血管内皮生长因子(VEGF)、血小板衍生生长因子(PDGF)、转化生长因子(TGF)、表皮生长因子(EGF)等生长因子,促进创面胶原沉积及血管新生。(3)芍药苷、隐丹参酮、蜂毒、回阳生肌汤等调节CXC趋化因子配体(CXCL)1、CXCL2、CC趋化因子配体(CCL)2、CCL3、基质细胞衍生... 相似文献