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681.
OA期刊数据库建设的关键问题研究——以农业、生物、化学为例 总被引:2,自引:0,他引:2
在开放获取迅速发展的今天,OA资源库的建设不仅是开放获取的重要内容,而且是开放获取发展的基础工程。首先分析了OA资源库建设的流程,重点阐述了在资源库建设过程中资源采集、存储、规范控制、资源更新维护的相关内容,详细分析了自动采集软件的工作原理,以及在开放获取这个大环境下,资源库建设的价值和意义. 相似文献
682.
A sandwich enzyme immunoassay for bovine interferon-γ and its use for the detection of tuberculosis in cattle 总被引:14,自引:0,他引:14
An in vitro cellular assay for bovine tuberculosis has recently been developed. This assay detects gamma-interferon released in response to specific antigen in a whole blood culture system. The bio-assay previously described for the detection of bovine gamma-interferon (IFN-gamma) has now been replaced with a sandwich enzyme immunoassay (EIA) which utilises two monoclonal antibodies to bovine IFN-gamma. The EIA detects less than 25pg/ml of recombinant bovine IFN-gamma and is specific for biologically active bovine IFN-gamma; and does not detect bovine alpha or beta interferon. IFN-gamma from sheep, goat and buffalo, but not from pig, deer or man, are also recognised by the EIA. The bovine IFN-gamma EIA when used in conjunction with the whole blood culture system has resulted in a simple, rapid and sensitive in vitro assay for specific cell mediated immune responsiveness to M. bovis infection in cattle. 相似文献
683.
F. J. TENDILLO DVM PhD A. M. PERA DVM A. MASCIAS DVM M. SANTOS DVM LA. GÓMEZ DE SEGURA DVM PhD F. SAN ROMÁN DVM PhD J.L. CASTILLO-OLIVARES MD PhD 《Veterinary surgery : VS》1995,24(1):73-77
To determine cardiopulmonary and analgesic effects of lidocaine, alfentanil, and xylazine in pigs anesthetized with isoflurane, 18 healthy Landrace-Large White pigs were studied (six for each drug). General anesthesia was induced with isoflurane in O2 and maintained with 1% to 1.2% end-tidal ISO, ensuring presence of a pain response before epidural drug administration. Heart rate (HR), arterial blood pressures (AP), cardiac output (CO), pulmonary arterial pressure, pulmonary capillary wedge pressure (PCWP), central venous pressure, respiratory rate (RR), tidal volume (TV), minute volume (MV), arterial blood gas data, core temperature (CT), and analgesic effects (by pricking the lumbar area and the abdominal wall) were determined at various times (2, 5, 15, 30, 45, 60, and 90 minutes) after epidural administration of lidocaine (5 μg/kg), alfentanil (5 μg/kg), or xylazine (0.2 mg/kg), all diluted in NaCl 0.9% to 0.5 mL/kg. Statistical analysis included two-way analysis of variance for repeated measures and the least significant difference test for determining differences among means. A probability level of P <.05 was used. The following results were statistically significant decreases in systolic AP, HR, TV, RR, MV, CT, pH, PaO2 , and TCO2 and increases in PCWP, PaCO2 , and HCO3 after LID. After ALF, only CT and HCO3 decreased. Core temperature and TV decreased after XYL. Lidocaine provided 45 to 60 minutes of analgesia. Alfentanil had no analgesic effects, and xylazine provided 90 minutes of analgesia. The authors conclude that xylazine, when injected epidurally, provides suitable analgesia in isoflurane-anesthetized pigs. 相似文献
684.
685.
SUMMARY Effects of body weight, condition score, ovarian cyclic status and insemination regimen on pregnancy rates were investigated in 164 Bos indicus heifers synchronised with norgestomet-oestradiol and pregnant mare serum gonadotrophin (PMSG). Oestrus detection techniques were also compared. Heifers were inseminated at either a fixed time (group 1, n = 83) of 48.0 ± 0.2 h (mean ± SEM) after implant removal or at 8.9 ± 0.5 h after oestrus was detected (group 2, n = 81). Group 2 heifers that were not detected in oestrus by 72 h after implant removal were inseminated at that time. Oestrus was detected for the purpose of insemination using heatmount detectors. Tail-paint and oestrogen treated, chin-ball harnessed steers were used to compare the efficiency of oestrus detection. The probability of ovarian cyclicity increased with increasing body weight and condition score (P < 0.001). A higher proportion of heifers that were acyclic at the commencement of treatment, compared with cyclic heifers, were detected in oestrus at the time of insemination in the fixed-time inseminated group (P <0.01). Analysis of covariance revealed that intervals from implant removal to oestrus were influenced by ovarian cyclic status (P < 0.01) and insemination group (P < 0.05). A higher pregnancy rate (%± SEM) was obtained in acyclic compared with cyclic heifers in the group 1 heifers (50.0 ± 10 vs 28.1 ± 6; P = 0.055) but not among the group 2 heifers (45.8 ± 10 vs 49.1 ± 7; P = 0.787). The probability of pregnancy was found to be associated negatively with body weight (P = 0.01) while a higher pregnancy rate was obtained in the group 2 compared with group 1 heifers (48.2%vs 34.9%; P = 0.093). The efficiency of oestrus detection was highest using heatmount detectors compared with tail-paint and chin-ball harnessed steers (90.7%vs 37.0% and 23.5%, respectively; P < 0.0001). We conclude that pregnancy rates can be increased in extensive environments when insemination follows oestrus detection using heatmount detectors compared with a fixed-time insemination. The fertility of heifers inseminated at a fixed time is influenced by ovarian cyclic status due to its influence on oestrus-to-insemination intervals. 相似文献
686.
Efficiency of inspection procedures for the detection of tuberculous lesions in cattle 总被引:2,自引:0,他引:2
LA CORNER L. MELVILLE† K. McCUBBIN‡ KJ SMALL† BS McCORMICK§ PR WOOD JS ROTHEL 《Australian veterinary journal》1990,67(11):389-392
The sensitivity of the abattoir inspection procedure introduced for Australian export beef in 1976 was compared to a detailed necropsy procedure for the detection of tuberculous lesions in cattle. In a sample of cattle that were reactors to the tuberculin test, abattoir inspection failed to detect an estimated 47% of cattle with lesions. The detailed necropsy examination of cattle with lesions of tuberculosis identified 21 sites of infection compared with 13 to 18 in cattle examined by routine meat inspection procedures. Of the lesions detected during detailed necropsy, 15.9% did not involve the thoracic cavity or the medial retropharyngeal lymph nodes. The failure to detect lesions during abattoir inspection has its greatest significance in an animal with a single lesion. If the 245 cattle found with single lesions during detailed necropsy had been examined by abattoir inspection using the 1976 or the 1986 procedures, 0.8 and 8.9%, respectively, of these animals would not have been detected because the diseased tissues would not have been examined. If meat inspection is to provide an effective means of monitoring the level of bovine tuberculosis during the final stages of eradication, a procedure no less sensitive than that introduced in 1976 should be used. 相似文献
687.
Gene cloning,prokaryotic expression,purification and characterization of CAD-caspase activated DNase
AIM:To construct a the plasmid pCool-GST-ICAD/CAD that expresses the CAD protein with biological function in E.coli BL21(DE3)strain.METHODS:CAD was amplified by PCR and inserted into pCool-GST-ICAD to create pCool-GST-ICAD/CAD.The plasmid was checked and transfected into BL21 for expression.The expressed protein were purified by using the GST affinity column,ion exchange and the gel filtration.Protein purity was checked by SDS-PAGE.CAD activity was checked by DNA fragmentation test.RESULTS:Plasmid pCool-GST-ICAD/CAD was constructed as design.The expression of GST-ICAD/CAD protein complex at mg level was observed.After purification,ICAD/CAD protein complex were obtained.Two clear protein bands were shown on SDS-PAGE.The DNA fragmentation test shows that the purified CAD protein indeed had the nonspecific DNase activity.CONCLUSION:Cloning and purification of CAD protein was successful with intact biological activity. 相似文献
688.
为探讨水牛SOX2基因的转录调控机制,本试验克隆获得其长2555 bp 的5'调控序列片段,结合生物信息分析设计了-2263、-1816、-1275、-660和-407 bp 5个缺失体,并分别构建其EGFP表达报告载体,通过生产转基因早期胚胎和转染水牛胎儿成纤维细胞分析各缺失体片段的转录活性。结果发现,除-407 bp以外的各缺失体在猪4.5 d早期胚胎细胞中均能成功启动下游EGFP的表达,且随着片段缩短,其转录活性呈极显著递减趋势(P<0.01);而转染水牛成纤维细胞48 h后,除p-407-EGFP以外的各缺失体报告载体转染组均观察到少数细胞发光,转录活性两两之间差异均极显著(P<0.01),转录活性从高到底排布分别为-2263、-660、-1275和-1816 bp。p-407-EGFP载体在胚胎水平和细胞水平均未观察到荧光。以上结果表明,-660~-407 bp是构成水牛SOX2基因表达不可缺失的部分,-2263~-1816 bp中有非多能细胞特异性的增强子元件存在,而-1816~-1275 bp和-1275~-660 bp均含有多能性细胞特异性的增强子元件。 相似文献
689.
以大喇叭杜鹃(Rhododendron excellens)为研究对象,研究了蔗糖、硼酸及CaCl2单因子及正交试验对其四合花粉萌发和花粉管生长的影响。结果表明,蔗糖、硼酸和CaCl2及3因子交互效应对大喇叭杜鹃的四合花粉萌发率、单花粉粒萌发数量及单花粉粒花粉管长度均有显著影响;最适蔗糖、硼酸和CaCl2溶液浓度分别为80g/L、100mg/L、80mg/L;正交试验的最佳配方组合是:80g/L蔗糖+50mg/L H3BO3+40mg/L CaCl2。 相似文献
690.
研究纤维素酶和碱性蛋白酶联合作用提取绿茶茶渣中蛋白质的工艺。以提取温度、加酶量、pH值、提取时间为参考因素设计实验,响应面设计确定最佳提取条件。结果表明,纤维素酶酶解最佳工艺:温度41℃、加酶量2%、pH值6.4、时间64 min,蛋白质提取率6.58%。碱性蛋白酶酶解工艺:温度60℃、加酶量2%、pH值8.7、时间90 min,蛋白质提取率20.93%。最终双酶联合提取茶叶蛋白质的提取率为32.18%。 相似文献