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排序方式: 共有811条查询结果,搜索用时 140 毫秒
61.
A CpG-enriched recombinant plasmid (pUC18-CpG) as an adjuvant of FMD killed vaccine was tested for immunization and vaccination challenge in a porcine model. Our preliminary results had indicated that the recombinant plasmid could enhance the humoral immune response triggered by the traditional oil-adjuvant vaccine after the initial inoculation. A subsequent vaccination-challenge test showed an increased PD(50) value. Thus, coadministration of the recombinant plasmid with the oil-adjuvant vaccine helped illicit an immune response earlier than that elicited by giving the vaccine alone. Our results showed that pUC18-CpG can be a potent immunoadjuvant for the traditional FMD killed vaccine and can greatly enhance the traditional vaccine's efficacy when given in combination with it.  相似文献   
62.
Aims: To prepare commercially acceptable formulations of Bacillus subtilis CPA‐8 by spray‐drying with long storage life and retained efficacy to control peach and nectarine brown rot caused by Monilinia spp. Methods and Results: CPA‐8 24‐h‐ and 72‐h‐old cultures were spray dried using 10% skimmed milk, 10% skimmed milk plus 10% MgSO4, 10% MgSO4 and 20% MgSO4 as carriers/protectants. All carriers/protectants gave good percentages of powder recovery (28–38%) and moisture content (7–13%). CPA‐8 survival varied considerably among spray‐dried 24‐h‐ and 72‐h‐old cultures. Seventy‐two hours culture spray dried formulations showed the highest survival (28–32%) with final concentration products of 1·6–3·3 × 109 CFU g?1, while viability of 24‐h‐old formulations was lower than 1%. Spray‐dried 72‐h‐old formulations were selected to subsequent evaluation. Rehydration of cells with water provided a good recovery of CPA‐8 dried cells, similar to other complex rehydration media tested. Spray‐dried formulations stored at 4 ± 1 and 20 ± 1°C showed good shelf life during 6 months, and viability was maintained or slightly decreased by 0·2–0·3‐log. CPA‐8 formulations after 4‐ and 6 months storage were effective in controlling brown rot caused by Monilinia spp. on nectarines and peaches resulting in a 90–100% reduction in disease incidence. Conclusions: Stable and effective formulations of biocontrol agent B. subtilis CPA‐8 could be obtained by spray‐drying. Significance and Impact of the Study: New shelf‐stable and effective formulations of a biocontrol agent have been obtained by spray‐drying to control brown rot on peach.  相似文献   
63.
As part of measles elimination effort, evaluation of the vaccination program and real-time assessment of the epidemic dynamics constitute two important tasks to improve and strengthen the control. The present study aimed to develop an epidemiological modeling method which can be applied to estimating the vaccine efficacy at an individual level while conducting the timely investigation of the epidemic. The multivariate renewal process model was employed to describe the temporal evolution of infection by vaccination history, jointly estimating the time-dependent reproduction number and the vaccine efficacy. Analyzing the enhanced surveillance data of measles in Aichi prefecture, Japan from 2007-08, the vaccine efficacy was estimated at 96.7% (95% confidence interval: 95.8, 97.4). Using an age structured model, the vaccine efficacy among those aged from 5-19 years was shown to be smaller than that among those from 0-4 years. The age-dependent vaccine efficacy estimate informs the age-groups to be targeted for revaccination. Because the estimation method can rest on readily available epidemiological data, the proposed model has a potential to be integrated with routine surveillance.  相似文献   
64.
叶剑飞  曾仲意 《蛇志》2012,24(2):122-123
目的观察蛇毒清合剂对蝮蛇咬伤的临床疗效。方法选择2008年11月~2011年11月我院收治的蝮蛇咬伤患者62例,随机分成两组,其中观察组31例,在常规治疗的基础上加服蛇毒清合剂,对照组31例采用常规治疗。比较两组患者血清酶学3项(CK、LDH、AST)、肿胀消退时间、疼痛缓解情况、肾功能衰竭、呼吸衰竭发生率、局部组织坏死发生率、致残率以及住院时间。结果观察组的血清酶学3项(CK、LDH、AST)、肿胀消退时间、疼痛缓解情况、肾功能衰竭、呼吸衰竭发生率、局部组织坏死发生率、致残率以及住院时间均明显优于对照组(均P〈0.05)。结论蛇毒清合剂治疗对蝮蛇咬伤有显著疗效。  相似文献   
65.
简单介绍目前疫苗效力检验的方法、黏膜抗体的功能及其在实验室疫苗效果效力评价中的应用,提出了黏膜抗体作为疫苗免疫效力试验的替代指标或免疫监测的主要抗体的建议。  相似文献   
66.
目的:探讨CO2激光联合胸腺五肽治疗尖锐湿疣的临床疗效。方法:将我院2010年2月-2011年8月期间收治的82例尖锐湿疣患者随机分为两组,治疗组50例采用CO2激光器治疗联合胸腺五肽肌注;对照组32例单纯采用CO2激光器治疗;两组治疗疗程结束后观察临床疗效。结果:治疗组50例,一次治愈者46例,占92%;二次治愈者4例,占8%。对照组32例,一次治愈者19例,占59.4%;二次治愈者13例,占40.6%。两组一次治愈率比较差异明显,具有统计学意义(P<0.05)。两组术后局部轻度水肿和疼痛,无需处理1~3天缓解或痊愈。结论:CO2激光联合胸腺五肽治疗尖锐湿疣临床疗效好,并具有治疗简便,术后不良反应少,治愈率高等特点。  相似文献   
67.
目的:观察高压氧辅助治疗重型颅脑损伤的临床疗效。方法:68例重型颅脑损伤患者随机分为观察组和对照组各34例,所有患者均根据病情选择手术或保守治疗,观察组在患者病情稳定后加用高压氧辅助治疗,治疗结束后比较两组患者的临床疗效。结果:观察组治疗有效率为91.2%,显著高于对照组的76.5%(P<0.05);治疗后1周和2周观察组的GCS评分均显著高于对照组(P<0.05),治疗后6个月观察组的GOS评分显著高于对照组(P<0.05);治疗后两组患者脑动脉血流速度均较治疗前有明显的改善(P<0.05),且观察的的改善情况优于对照组。结论:选择高压氧辅助治疗重型颅脑损伤的临床疗效好,可改善患者的临床情况和预后,值得临床应用。  相似文献   
68.
In vivo experiments were designed to verify the analgesic effect of Dragon’s Blood and the material basis for this effect. Extracellular microelectrode recordings were used to observe the effects of Dragon’s Blood and various combinations of the three components (cochinchinenin A, cochinchinenin B, and loureirin B) extracted from Dragon’s Blood on the discharge activities of wide dynamic range (WDR) neurons in spinal dorsal horn (SDH) of intact male Wistar rats evoked by electric stimulation at sciatic nerve. When the Hill's coefficients describing the dose-response relations of drugs were dif-ferent, based on the concept of dose equivalence, the equations of additivity surfaces which can be applied to assess the interaction between three drugs were derived. Adopting the equations and Tal-larida's isobole equations used to assess the interaction between two drugs with dissimilar dose-response relations, the effects produced by various combinations of the three components in modulating the evoked discharge activities of WDR neurons were evaluated. Results showed that Dragon’s Blood and its three components could inhibit the evoked discharge frequencies of WDR neurons in a concentration-dependent way. The Hill's coefficients describing dose-response relations of three components were different. Only the combined effect of cochinchinenin A, cochinchinenin B and loureirin B was similar to that of Dragons Blood. Furthermore, the combined effect was synergistic. This investigation demonstrated that through the synergistic interaction of the three components Dragon’s Blood could interfere with the transmission and processing of pain signals in spinal dorsal horn. All these further proved that the combination of cochinchinenin A, cochinchinenin B, and loureirin B was the material basis for the analgesic effect of Dragon’s Blood.  相似文献   
69.
Clinical reports indicate that malaria-infected asplenic patients have a reduced capacity for parasite clearance despite intensive antimalarial therapy. The aim of this study was to evaluate the efficacy of dihydroartemisinin in an asplenic murine malaria model. Mice were inoculated with Plasmodium berghei parasitised erythrocytes and received a single dose of dihydroartemisinin 56 h later, at 2-5% parasitaemia. Haematology, liver biochemistry and histopathology of key organs were performed to evaluate organ response to malaria infection. The nadir parasitaemia occurred 20 h after dihydroartemisinin administration, falling 2.8- to 6.0-fold and 2.7- to 6.9-fold in asplenic and intact mice, respectively, (10-100 mg/kg). Histopathology indicated increased stimulation of liver function/activity during malaria infection of asplenic mice (as compared to intact mice). Overall efficacy of single-dose dihydroartemisinin treatment in asplenic mice was similar to intact mice although the rate of recrudescence in asplenic mice was significantly greater than intact mice at 30 and 100 mg/kg. The asplenic murine malaria model could be used in pre-clinical studies of splenic function and clearance of malaria parasites, pathophysiological studies or antimalarial drug efficacy in asplenia.  相似文献   
70.
Bosier B  Lambert DM  Hermans E 《FEBS letters》2008,582(28):3861-3867
Agonists acting at the CB1 cannabinoid receptor in N1E-115 neuroblastoma cells were found to activate MAPK family members with reciprocal efficacies. Thus, HU 210 robustly increased phosphorylation of ERK1/2 whereas CP 55,940 was more effective in activating JNK. The use of selected kinase inhibitors confirmed that distinct signalling cascades were involved in these responses. This reciprocal control of MAPK activity was correlated with the observation that HU 210- and CP 55,940-mediated regulations of tyrosine hydroxylase gene expression were respectively impaired by MEK and JNK inhibitors. These data indicate that complex interactions of the CB1 receptor with intracellular signalling partners controlling MAPK activities may explain the apparent disparities in cellular responses to functional selective agonists.  相似文献   
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