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81.
82.
双黄连滴丸的主要药效学研究   总被引:3,自引:0,他引:3  
目的:评价双黄连滴丸的主要药效,为临床合理使用提供参考。方法:解热试验、抗炎试验、抗菌试验。结果:双黄连滴丸口服灌胃给药剂量在10和3g/kg(含生药)时,对细菌内毒素引起的家兔体温升高具有良好的降解作用;口服灌胃给药剂量在20和6g/kg(含生药)时,能显著抑制腹腔注射醋酸(HAC)所致小鼠腹腔毛细血管通透性的增高和二甲苯所致的小鼠耳肿胀(P<0.01);能保护由腹腔射金黄色葡萄球菌引起的动物死亡;体外抗菌试验表明对金黄色葡萄球菌、流感杆菌、B型链球菌具有较好的抑菌作用(最低抑制菌浓度分别为40,40和160mg/ml含生药)。结论:双黄连滴丸具有解热、抗炎、抗菌作用。  相似文献   
83.
本文设计并合成了18个在苄基上带有不同体积取代基的2,4-二氨基-5-取代苄基嘧啶类化合物。测定了这些化合物对乳酪菌二氢叶酸还原酶及对鸡肝二氢叶酸还原酶的表观50%抑制作用。其中2,4-二氨基-5-(3′-羟基-4′-甲氧基)苄基、2,4-二氨基-5-(3′-甲氧基-4′-甲氧乙氧基)苄基嘧啶对上述二氢叶酸还原酶(DHFR)的选择性较好。  相似文献   
84.
筛窦癌发病率低,就诊时病期晚,5年无瘤生存率为30%~50%。由于解剖部位的限制以及局部浸润,放射和手术均有一定难度。作者回顾性分析皇家Margret医院1976~1994年收治的29例浸润性筛窦癌根治性放射治疗的疗效和影响预后因素。男性24例,女性4例,中位年龄62岁,中位随访时间4年。常有鼻出血、鼻塞、疼痛及视力改变等。起病到确诊的平均时间为9个月。27例吸烟,10例从事伐木或镍的开采与提炼。  治疗前均经临床及影像学检查。仅3例局限于筛窦,余侵犯鼻腔、蝶窦、眼眶、上颌窦、额窦及脑内等。T1…  相似文献   
85.
86.
The hexane, acetone, dichloromethane and methanol extracts of Combretum vendae A.E. van Wyk (Combretaceae), Commiphora harveyi (Engl.) Engl. (Burseraceae), Khaya anthotheca (Welm.) C.DC (Meliaceae), Kirkia wilmsii Engl. (Kirkiaceae), Loxostylis alata A. Spreng. ex Rchb. (Anacardiaceae), Ochna natalitia (Meisn.) Walp. (Ochnaceae) and Protorhus longifolia (Bernh. Ex C. Krauss) Engl. (Anacardiaceae) were screened for their antimicrobial activity. The test organisms included bacteria (Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus), and fungi (Aspergillus fumigatus, Candida albicans, Cryptococcus neoformans, Microsporum canis and Sporothrix schenckii). A simple bioautographic procedure, involving spraying suspensions of the bacteria or fungi on thin layer chromatography (TLC) plates developed in solvents of varying polarities was used to detect the number of antibacterial and antifungal compounds present in the extracts. All the extracts had antimicrobial activity against at least one of the test microorganisms. This activity was denoted by white spots against a red-purple background on the TLC plates after spraying with tetrazolium violet. Twenty seven TLC plates; 9 for each solvent system and 3 different solvent systems per organism were tested in the bioautographic procedure. Of the bacteria tested, S. aureus was inhibited by the most compounds separated on the TLC plates from all the tested plants. Similarly, growth of the fungus C. neoformans was also inhibited by many compounds present in the extracts. Loxostylis alata appeared to be the plant extract with the highest number of inhibition bands when compared with other plants tested against both bacteria and fungi. This species was selected for in depth further study.  相似文献   
87.
Rhabdomyosarcoma (RMS) is the most common soft tissue tumour in children, with the head and neck region accounting for 35–40% of cases. Nasopharyngeal RMSs tend to grow rapidly and invade adjacent structures. Both the Intergroup Rhabdomyosarcoma Studies and the European Studies have established that the ideal management of this disease is multimodal, using a combination of surgery, chemotherapy and radiotherapy. This case series examines the role of radiotherapy in the management of paediatric nasopharyngeal RMSs, with particular reference to long-term morbidity and disease-free survival. The cases of five children with nasopharyngeal RMS were reviewed and a systematic review of the literature contained in the PubMed databases was conducted to establish 24 individually detailed cases. Management in all patients was multimodal, using a combination of chemotherapy, radiotherapy as well as surgery. External beam radiotherapy is an integral component of treatment for nasopharyngeal RMSs. With more patients surviving for longer periods, more long-term sequelae of radiotherapy have been reported. Complications include sensorineural deafness, endocrine manifestations following radiation of the pituitary gland, cranial nerve palsies, second malignancies within the radiation field, cataract formation, retinopathy and growth disturbance. Morbidity from radiotherapy may be considerable and depends on the field and dose of radiation. Current advances in radiotherapy are aimed at improving the rate of tumour control and reducing such complications. Recent improvements in imaging and conformal techniques have the potential to reduce the morbidity associated with radiotherapy in this cohort.  相似文献   
88.
89.
目的:探讨血浆脂联素(APN)水平在冠心病患者中的临床意义,以及其在冠心病发生、发展中的作用。方法:选取确诊为冠心病患者共80例,其中稳定型心绞痛组45例,不稳定型心绞痛组35例,并且选取30例正常健康人作为对照组,检测血浆APN水平,同时检测LDL-C、HDL-C,并对检测结果进行分析。结果:冠心病患者APN水平明显低于对照组,两组比较差异有统计学意义(P<0.05);不稳定型心绞痛组APN水平低于稳定型心绞痛组(P<0.05)。结论:脂连素可能为冠心病的一个保护因子,其与冠心病的发生发展呈负相关,为诊断冠心病提供了临床依据。  相似文献   
90.
Askew  DS; Ihle  JN; Cleveland  JL 《Blood》1993,82(7):2079-2087
The inappropriate expression of c-myc in cells deprived of growth factors has recently been implicated in the activation of programmed cell death (apoptosis). The studies described here examine the ability of interleukin-3 (IL-3) or erythropoietin (Epo) to suppress apoptosis that occurs in association with enforced myc expression during cell cycle arrest of a murine IL-3-dependent myeloid progenitor cell line, 32D. G1 arrest was observed when culturing 32D cells to high density in medium supplemented with IL-3, or at subconfluent densities in medium supplemented with Epo. Under both conditions, endogenous c-myc expression was downregulated and viability was maintained. In clones of cells in which c-myc is constitutively expressed from a retroviral vector, enforced c-myc expression was associated with the activation of apoptosis at high cell densities. Similarly, enforced c-myc expression was deleterious to cell survival when these cells were cultured in Epo, as apoptosis was evident within 6 hours. The results support the concept that inappropriate c-myc expression activates apoptosis and that neither IL-3 nor Epo can suppress this program under these conditions.  相似文献   
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