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121.
122.
高分子染料是一类本身固有颜色的高分子化合物,它兼有染料和高聚物的双重性质。因此既可作为色料也可作为高聚物而应用于许多领域。本文较详细阐述了聚合染料的种类,合成方法及应用情况。  相似文献   
123.
124.
1. (+)-Hydrastine is a phthalide isoquinoline alkaloid, isolated from Corydalis stricta. It has the same 1S,9R configuration as the competitive GABAA receptor antagonist bicuculline and is the enantiomer of the commercially available (-)-hydrastine. 2. (+)-Hydrastine (CD50 0.16 mg kg-1, i.v.) was twice as potent as bicuculline (CD50 0.32 mg kg-1, i.v.) as a convulsant in mice. This action was stereoselective in that (+)-hydrastine was 180 times as potent as (-)-hydrastine. 3. (+)-Hydrastine was a selective antagonist at bicuculline-sensitive GABAA receptors in the guinea-pig isolated ileum. It did not influence phaclofen-sensitive GABAB receptors or acetylcholine receptors in this tissue. (+)-Hydrastine was a competitive antagonist of GABAA responses (pA2 6.5) more potent than bicuculline (pA2 6.1). 4. When tested against the binding of [3H]-muscimol to high affinity GABAA binding sites in rat brain membranes, (+)-hydrastine (IC50 2.37 microM) was 8 times more potent than bicuculline (IC50 19.7 microM). 5. As an antagonist of the activation of low affinity GABAA receptors as measured by the stimulation by GABA of [3H]-diazepam binding to rat brain membranes, (+)-hydrastine (IC50 0.4 microM) was more potent than bicuculline (IC50 2.3 microM). 6. (+)-Hydrastine, 10 nM to 1 mM, did not inhibit the binding of [3H]-(-)-baclofen to GABAB binding sites in rat brain membranes.  相似文献   
125.
Non-tuberculous mycobacterial keratitis: a study of 22 cases.   总被引:11,自引:0,他引:11       下载免费PDF全文
AIM: To investigate causes and clinical findings of non-tuberculous mycobacterial keratitis, and to study its response to topical antibiotic therapy and surgical extirpative keratectomy. METHOD: A single centre, retrospective review of 22 patients with non-tuberculous mycobacterial keratitis seen in a 3 year period. Laboratory diagnoses were established with Ziehl-Nielsen acid fast staining and Löwenstein-Jensen cultures. RESULTS: In 20 patients (91%), there was an antecedent history of foreign body eye trauma (18 patients) or elective surgery (two patients). There were 19 cases of Mycobacterium chelonei, and three of M fortuitum. Clinical signs included epithelial defects, satellite or ring stromal infiltrates, crystalline keratopathy, and hypopyon. For topical antibiotic therapy, 20 patients received amikacin, while one patient received rifampin and another received ciprofloxacin, each in accordance with the results of the in vitro drug sensitivities. An extirpative keratectomy was performed in 15 cases; four of these cases additionally required a temporary conjunctival flap in order to finally eradicate the infection. At the end of the follow up period (median 18 months; range 3 months to 3 years) all eyes were stable and free of infection, with 19 (86%) having final visual acuities of 20/200 or better. CONCLUSION: Early clinical recognition and prompt laboratory diagnosis, together with aggressive topical antibiotic therapy and early keratectomy, may shorten morbidity and improve the clinical outcome of non-tuberculous mycobacterial keratitis.  相似文献   
126.
本文报告了1990年5月以来脑干区大型、复杂占位病变15例.其中,位于脑干内3例,脚间窝2例,岩尖部4例,全岩骨区1例,全斜坡区2例,第四脑室内3例.本组采用以扩大了的岩骨入路为主的联合入路,行肿瘤全切除8例,次全切除5例.2例仅作了活检加减压术.除1例死亡外,均恢复良好.本文结合文献,对脑干区手术入路进行了讨论.  相似文献   
127.
The behavior of marker proteins of neurons (gamma-enolase) and glial cells (alpha-enolase, beta-S100 protein and creatine kinase-B) was investigated quantitatively by using enzyme immunoassay systems in toluene-exposed rat brains. Three groups of animals were exposed to toluene vapor at 300 ppm, 1000 ppm, and 3000 ppm, respectively, 8 h/day, 6 days/week, for 2 weeks. After subacute repeated solvent exposure, both neuron-specific gamma-enolase and glial marker proteins displayed an overall concentration-dependent increase tendency in separate brain regions. In cerebrum, only the 3000 ppm group showed a significant increase in alpha-enolase by 27% and creatine kinase-B (CK-B) by 26%. alpha-Enolase and gamma-enolase exhibited a pronounced elevation in cerebellum relative to other brain regions, while beta-S100 protein appeared to be the most markedly altered marker in brainstem. The development of gliosis, which is a frequent phenomenon following CNS damage, is presumed to be responsible for the elevation of glial marker content. Energy metabolism disruption in brain tissues may also bring about the compensatory oversynthesis of glycolytic enzymes such as gamma-enolase, alpha-enolase and CK-B. The dose-dependent alteration patterns following toluene exposure suggest the feasibility of using these brain specific markers to evaluate solvent-induced CNS effects.  相似文献   
128.
Circulating antisperm antibodies (AsAb) and immunosuppressive material in seminal plasma (SPIM)were determined by solid-phase enzyme staining assay and anticomplement test respectively in 686 patients with abortion (including 285 couples) . 241 fertile couple served as control. It's found that the positive rate of AsAb in infertile patients was significantly higher than that in fertile control,being 36.6% vs 3.3% (P<0.001). AsAb was even more offen detected in recurrent aborting patients. Male patients whose spouses aborted 2-6 fetuses had significantly less SPIM than control, sperm count and sperm motility were also significantly decreased. But the incidence of pyospermia was significantly greater than that in control. It is concluded that AsAb and SPIM have played an important role in the development of recurrent abortions.  相似文献   
129.
运用二元碱氮置换吸附红外光谱法、分子筛孔径分布测定技术、XPS技术,考察了丝光沸石表面酸性与孔结构的相互关系、钯在丝光沸石上分布情况和价态及其与沸石的相互作用。结果表明,随着丝光沸石脱铝程度的增加,表面出现大量不规整晶格,存在较多的次级孔道。强质子酸中心主要分布在它的“外表面”。钯在其表面富集,并与“外表面”上的质子酸中心协同作用,促进了轻质烷烃异构化反应。  相似文献   
130.
杨清林  黄贞明 《中成药》1995,17(10):13-14
采用薄层扫描法对复脉定冲剂中远志有效成分3,4,5-三甲氧基反式肉桂酸乙酯的含量进行测定。方法简单、快速,结果可靠,可作为该制剂的质控标准。  相似文献   
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