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81.
S. Shaikh D. A. Collier P. Sham L. Pilowsky T. Sharma L. K. Lin M. A. Crocq M. Gill R. Kerwin 《American journal of medical genetics. Part A》1995,60(6):541-545
We have examined the hypothesis that a variable number of tandem repeats in the third cytoplasmic loop of the dopamine D4 receptor influences clinical response to clozapine using a sample of 189 schizophrenic patients. Alleles of the 48-bp repeat, which range from two to ten copies in the normal human population, were analysed by the polymerase chain reaction using genomic DNA as template. Association between these alleles and response to clozapine was tested using the difference in pre-and post-treatment GAS scores as a measure of response. We found no statistically significant variation between genotypic groups and response by analysis of variance. We conclude that the variation of the number of 48-bp repeats alone does not determine response to clozapine. Larger studies are underway to determine if there is a more subtle relationship with sequence variation within the repeats or at other polymorphic sites within the gene that may provide evidence for a component of clozapine's action being at D4 receptors. © 1995 Wiley-Liss, Inc. 相似文献
82.
本文对SOD的紫外分光光度法测定进行了实用性研究。结果表明,本文方法具有用血量少,重现性好,快速、灵敏,试剂廉价等优点。西宁地区与平原地区人群的比较测定显示,前者SOD活性明显高于后者(P<0.01)。 相似文献
83.
84.
Penetration of Schistosoma japonicum cercaria into host skin. 总被引:1,自引:0,他引:1
The anterior part of Schistosoma japonicum cercaria is a specialized head organ which can slightly stretch out and retract. There are three different types of large unicellular glands in cercarial body, consisting of one head gland, 2 pairs of pre- and 3 pairs of postacetabular glands. These glands differ in position, gross feature, histochemistry and functions. Both polysaccharase and protease activities are demonstrated in the secretions from these glands. Mode of cercarial penetration is described in detail and the penetration is effected by a combination of lytic secretions and mechanical movements. The schematic representation of the process of cercarial penetration is presented. The dynamic distributions of schistosomula in skin at different time intervals after skin penetration in various mammalian hosts are shown. Some newly transformed schistosomula die while penetrating into the skin of 7 mammalian species and the mortality rate varies with the host species, and that can also be affected by the age of cercariae following emergence from the snail. Some physiological aspects between cercariae and newly transformed schistosomula are compared. In contrast to cercariae, schistosomula are saline-adapted and water-intolerant. They were modified histochemically and antigenically.
相似文献
85.
J Q Koenig D S Covert M S Smith G van Belle W E Pierson 《Toxicology and industrial health》1988,4(4):521-532
Separate exposures to 0.12 ppm ozone (O3) or 0.18 ppm nitrogen dioxide (NO2) have not demonstrated consistent changes in pulmonary function in adolescent subjects. However, in polluted urban air, O3 and NO2 occur in combination. Therefore, this project was designed to investigate the pulmonary effects of combined O3 and NO2 exposures during intermittent exercise in adolescent subjects. Twelve healthy and twelve well-characterized asthmatic adolescent subjects were exposed randomly to clean air or 0.12 ppm O3 and 0.30 ppm NO2 alone or in combination during 60 minutes of intermittent moderate exercise (32.5 1/min). The inhalation exposures were carried out while the subjects breathed on a rubber mouthpiece with nose clips in place. The following pulmonary functional values were measured before and after exposure: peak flow, total respiratory resistance, maximal flow at 50 and 75 percent of expired vital capacity, forced expiratory volume in one second and forced vital capacity (FVC). Statistical significance of pulmonary function changes was tested by analysis of covariance for repeated measures. After exposure to 0.12 ppm O3 a significant decrease was seen in maximal flow at 50% of FVC in asthmatic subjects. After exposure to 0.30 ppm NO2 a significant decrease was seen in FVC also in the asthmatic subjects. One possible explanation for these changes is the multiple comparison effect. No significant changes in any parameters were seen in the asthmatic subjects after the combined O3-NO2 exposure or in the healthy subjects after any of the exposures. 相似文献
86.
A Coagulation Factor IX-Deficient Mouse Model for Human Hemophilia B 总被引:25,自引:10,他引:15
Lin Hui-Feng; Maeda Nobuyo; Smithies Oliver; Straight David L.; Stafford Darrel W. 《Blood》1997,90(10):3962-3966
87.
The total sequence-specific 1H assignment for the alpha 185-peptide was accomplished by analysis of COSY spectra along with spin-decoupling and confirmatory NOE difference experiments. Some ambiguities in the assignments were successfully addressed utilizing additional peptides with selective amino acid substitutions. The chemical shifts of several of the C alpha H resonances, along with evidence for a slowly exchanging amide at Thr-191 suggest that the alpha 185-peptide may contain a certain amount of non-random coil structure. The role of any such ordered structure in the mechanism of binding to alpha-bungarotoxin remains to be determined. The assignment of the peptide 1H resonances will facilitate the analysis and identification of chemical shift perturbations observed upon formation of the complex between alpha-bungarotoxin and the alpha 185-peptide [7]. 相似文献
88.
临床输液监控系统的设计 总被引:5,自引:0,他引:5
本文针对临床输液过程中出现的漏、停、输液速度改变等各种问题,讨论了一由单台微机和多个单片机通讯实现的多床输液自动监控、自动反应、自动报答系统的可行性,并给出了主要部分的硬件、软件设计方法。 相似文献
89.
Propionic acidemia is a rare hereditary disease which is an autosomal recessive disorder. Defect of propionyl CoA carboxylase results in abnormal accumulation of propionate and its metabolites which interfere the pathway of glycine cleavage and the urea cycle. This organic acidemia is characterized by a wide spectrum of clinical and biochemical findings, including recurrent vomiting, difficult feeding, lethargy, hypotonia, metabolic ketoacidosis, hyperglycinemia and hyperammonemia during the acute episodes. We present a male newborn infant who sustained this disorder and was managed successfully with blood exchange transfusion, peritoneal dialysis, supplemented with sodium benzoate and sodium bicarbonate therapy. Urine gas chromatography disclosed significant elevation of propionate and its metabolites which subsided 2 days after peritoneal dialysis. Special designed formula was then given with restriction of protein intake and supplement with sodium benzoate and sodium carbonate. Prenatal genetic counseling is necessary in further pregnancy. Diagnosis can be obtained when propionyl CoA carboxylase activity is low in cultured amniotic fluid cells or chorion villi sample or when there is abnormally high methylcitrate level in amniotic fluid. 相似文献
90.
林尚泽 《中华耳鼻咽喉头颈外科杂志》1994,(4)
报道1例严重鼻衄伴高血压、动脉硬化患者,经常规方法止血无效,行患侧颌内动脉超选择性栓塞术。术后鼻出血停止,但出现脑梗塞、昏迷,经抢救无效,于术后第9天死亡。认为对有动脉硬化的患者,应不用或慎用超选择性动脉栓塞术。 相似文献