剪切力对链霉菌谷氨酰胺转胺酶发酵的影响

考察了以摇瓶发酵过程中添加玻珠为剪切力,对链霉菌(Streptomyces sp.)HS-1发酵生产谷氨酰胺转胺酶的影响,在10 L发酵罐上不同搅拌转速对产酶的影响。结果显示,摇瓶发酵中,在种子阶段添加玻珠,提高剪切力不能促进产酶;在发酵阶段,加入4颗玻珠时,酶活相对最高,比对照增加20%;36 h时添加玻珠,与对照相比,酶活提高12%,菌体浓度增加40%,且氨基氮消耗明显。10 L发酵罐中,适宜的搅拌转速为250 r/min,36 h调整转速至250r/min,酶活比维持90 r/min提高21%。因此剪切力对谷氨酰胺转胺酶发酵有明显影响。     

磁珠法核酸自动提取仪在分子生物学领域的应用

磁珠法核酸自动提取仪可以简单、快速、高效和经济地实现各种标本核酸的自动提取。本文概述了核酸自动提取仪的原理及分类,磁珠法核酸自动提取仪原理、分类、特点及其在分子生物学领域的应用。     

不同方法提取高致病性禽流感及新城疫病毒RNA效果的比较分析

高致病性禽流感以及新城疫对禽养殖户危害巨大,应用荧光RT-PCR方法对高致病性禽流感、新城疫病毒进行检测在病原学检测中占据优势。而荧光RT-PCR检测的核心是核酸物质的提取。本文将离心柱内硅基质膜提取法（柱膜法）与磁珠法作比较,探讨更适合基层兽医实验室的核酸提取方式。     

应用磁珠免疫亲和层析法从猪卵泡液中提纯抑制素

采集猪卵泡液 ,用 70 %饱和度硫酸铵溶液沉淀后 ,分别过SephadexG 2 0 0柱和SephadexG 10 0柱 ,最后用磁珠免疫亲和层析法进一步提纯 ,使抑制素纯度从 12 4 μg·mg-1升至 39 4 μg·mg-1。PAGE电泳分析证明 ,提纯物只出现一条相对分子质量为 32 0 0 0的带 ,SDS PAGE电泳分析发现有两条相对分子质量分别为 14 0 0 0～ 15 0 0 0和 170 0 0～ 180 0 0的带 ,即β、α亚基。     

丝胶/海藻酸钠复合凝胶粒的制备及其结构性能表征

为了改良丝胶型药物载体的结构性能,将丝胶粉末与海藻酸钠溶液均匀混合后,采用氯化钙胶凝法制备了粒径为1.88 mm±0.15 mm的丝胶/海藻酸钠复合凝胶粒。红外光谱检测表明该复合凝胶粒中的丝胶与海藻酸钠之间以物理方式混和;差示扫描量热分析发现丝胶与海藻酸钠复合后,其结构稳定性有所提高;机械性检测表明丝胶/海藻酸钠复合凝胶粒具有更好的力学性能;溶胀性检测表明丝胶/海藻酸钠复合凝胶粒具有pH敏感溶胀性。研究结果表明丝胶/海藻酸钠复合凝胶粒使丝胶作为药物固定化载体的结构与性能得到改善,更有利于开发利用。     

研磨珠辅助提取茶树菇水溶性核苷酸工艺研究

本文以食用真菌茶树菇子实体为原料,采用研磨珠细胞破壁提取法,对其所含的核苷酸类物质进行提取。通过单因素实验,采用响应面分析法优化研磨珠辅助提取工艺参数,并确定最佳提取工艺条件为：研磨时间12min ,液料比为51:1,研磨珠装载量为12.5%,理论核苷酸得率为7.02%。进行二次多元回归拟合,通过回归分析检验多元回归方程模型显著。另外,通过验证试验,实际得率为（6.94±0.07）%,结果与模型符合良好,进一步说明拟合方程的可靠。与传统方法相比,本文采用的研磨珠破壁提取方法,不仅所得核苷酸产品提取率高,并且可大大缩短操作时间,为食用菌及核苷酸的新型生产工艺的开发提供了理论参考。     

Granulosa cell tumor in 8 African pygmy hedgehogs (Atelerix albiventris)

A retrospective study involving eight African pygmy hedgehogs histopathologically diagnosed with granulosa cell tumors was conducted. The age at onset was 2.2–4.5 years, with a median age of 3.6 years. The most common clinical signs were hematuria and abdominal distension, which were observed in >50% cases. Exploratory laparotomy was performed in all cases, and ovariohysterectomy or excision of the abdominal mass was performed. Patients with only hematuria survived for >250 days after surgery, whereas those with initial ascites showed recurrence of ascites or tumor growth and survived for approximately 130 days after surgery. Intraperitoneal injection of carboplatin was performed in three recurrent cases. In one of these three cases, the tumor mass disappeared. Hence, carboplatin can be considered a potential antineoplastic drug for the treatment of granulosa cell tumors.     

Efficacy and toxicity of carboplatin and cytarabine chemotherapy for dogs with relapsed or refractory lymphoma (2000–2013)

Medical records of 22 dogs treated with carboplatin (n = 8) or carboplatin and cytarabine (n = 14) chemotherapy for relapsed or refractory lymphoma between 2000 and 2013 were retrospectively reviewed. The clinical response rate was 18.2% (4/22). Median time to progression was 18 days (56 for responders; 12 for non‐responders, P = 0.0006). Median overall survival time was 28 days (109 for responders; 21 for non‐responders, P = 0.0007). Thrombocytopenia and neutropenia occurred in 84.2% (16/19) and 52.6% (10/19), respectively. Grade IV thrombocytopenia and neutropenia occurred in 56.3% (9/16) and 60.0% (6/10), respectively. Dogs that received both drugs were more likely to become neutropenic (P = 0.022) or thrombocytopenic (P = 0.001) than dogs receiving carboplatin alone. All responders received both drugs giving a 28.6% (4/14) response rate for the combination. Although some dogs responded to the combination, toxicity was high and the responses were not durable. With adequate supportive care, this protocol may be an acceptable rescue option for some dogs.     

工艺竹珠产品生产技术及其应用前景

本文介绍了生产工艺竹珠的几个技术环节。在毛竹资源丰富、劳动力富余、交通方便的地方,推广应用这一技术,将使毛竹深加工进入一个新的领域,具有良好的应用前景。     

Safety evaluation of combination carboplatin and toceranib phosphate (Palladia) in tumour‐bearing dogs: A phase I dose finding study

Combining conventional cytotoxic maximum tolerated dose (MTD) chemotherapy with low‐dose metronomic and/or anti‐angiogenic agents is a exciting area of oncologic research. The objective of this study was to establish the MTD, safety and adverse event (AE) profile of 1 such drug combination. This prospective phase I dose‐finding clinical trial assumed an open‐label 3 + 3 cohort design. Client‐owned dogs with 1 or more cytologically and/or histologically confirmed and macroscopically measurable, naive or recurrent, malignant tumours, were enrolled. No preference for tumour histology, grade or stage was expressed. Toceranib was administered at a dose of 2.75 mg kg^?1 by mouth (PO) every other day (EOD), and carboplatin administered intravenously (IV) every 21 days at a starting dose of 200 mg m^?2. A total of 25% dose escalation was proposed for carboplatin, to a maximum of 300 mg m^?2. AEs were graded according to the Veterinary Cooperative Oncology Group's common terminology criteria for AEs (VCOG‐CTCAE). Grade 3 haematologic or gastrointestinal AEs were nominated dose‐limiting. Response to therapy was evaluated according to the VCOG's revised RECIST criteria. Eleven dogs were enrolled. Tumour histologies included sinonasal carcinoma, osteosarcoma, thyroid carcinoma, melanoma and apocrine gland anal sac adenocarcinoma. MTDs of carboplatin and toceranib were identified as 200 mg m^?2 IV every 21 days and approximately 2.75 mg kg^?1 PO EOD, respectively. The dose‐limiting toxicity was neutropenia. Two dogs experienced a partial response, and 6 maintained stable disease. Combination carboplatin and toceranib chemotherapy was well‐tolerated. Clinical benefit was observed in most cases. This protocol warrants further investigation in phase II/III trials.