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91.

Background

Leishmaniasis is a worldwide disease prevalent in tropical and sub tropical countries. Many attempts have been made and different strategies have been approached to develop a potent vaccine against Leishmania. DNA immunisation is a method, which is shown to be effective in Leishmania vaccination. Leishmania Soluble Antigen (SLA) has also recently been used Leishmania vaccination.

Methods

The immunity generated by SLA and L. mexicana gp63 cDNA was compared in groups of 6 mice, which were statistically analysed by student t- test with the P-value of 0.05. SLA was administered by two different methods; intramuscular injection and injection of dendritic cells (DCs) loaded with SLA. L. mexicana gp63 cDNA was administered by the gene gun.

Results

Immunisation of BALB/c mice with L. mexicana gp63 resulted in high levels of Th1-type immune response and cytotoxic T lymphocytes (CTL) activity, which were accompanied with protection induced by the immunisation against L. mexicana infection. In contrast, administration of SLA, produced a mixed Th1/Th2-type immune responses as well as a high level of CTL activity but did not protect mice from the infection.

Conclusion

The results indicate higher protection by DNA immunisation using L. mexicana gp63 cDNA compared to SLA, which is accompanied by a high level of Th1 immune response. However, the CTL activity does not necessarily correlate with the protection induced by the vaccine. Also, gene gun immunisation is a potential approach in Leishmania vaccination. These findings would be helpful in opening new windows in Leishmania vaccine research.  相似文献   
92.
丁香水溶性化学成分的研究   总被引:2,自引:0,他引:2  
目的:研究丁香水溶性化学成分。方法:利用HP-20大孔吸附树脂、反相硅胶柱色谱、反相制备薄层色谱、制备型反相高效液相色谱进行分离,NMR和MS等方法进行结构鉴定。结果:从丁香干燥花蕾的水提物中分离鉴定了5个化合物,分别为槲皮素-3-O-葡萄糖醛酸苷(1),槲皮素-3-O-葡萄糖醛酸苷6″-甲酯(2),槲皮素-3-O-葡萄糖苷(3),丁香酚-β-芸香糖苷(4),杨梅酮(5)。结论:化合物1~4为首次从丁香属植物中分离得到。  相似文献   
93.
尚千涵  高其媛  杨婷  梁健  王乐  洒威  王玛丽  申智清  李忠虎 《中草药》2021,52(18):5782-5788
羊肚菌Morchella esculenta是子囊菌亚门的一种大型药食两用真菌,具有重要的经济价值和药用价值。然而近年来全球气候变化,导致羊肚菌属物种的栖息地破碎和片段化,加上消费者对羊肚菌美食的喜爱,过渡采挖造成羊肚菌属野生资源急剧减少,因此,急需对羊肚菌属物种资源进行保护。遗传多样性的时空分布是保护生物学的重要内容,遗传多样性关系到一个物种或类群的进化潜力和未来命运。生物基因组和进化的研究能够辅助挖掘物种深层次的优异基因资源,有利于从本质上对物种进行科学保护。从羊肚菌属的遗传多样性、遗传结构和家系关系以及基因组进化等的研究进展进行综述,以期为羊肚菌属资源的科学保护提供重要依据。  相似文献   
94.
Aim : To investigate whether infants with intrauterine growth retardation (IUGR) experience different changes in temperature and cortisol excretion after routine immunization compared with normal healthy infants. Methods : Overnight deep body temperature and urinary cortisol to creatinine ratios were measured on the night after immunization and a control night in normal and IUGR infants. Results : In 60 normal infants, first vaccination at about 10 wk of age led to a significant increase in minumum overnight temperature compared to the control night, mean rise 0.25°C (95% CI, 0.12 to 0.38). In 35 IUGR infants the mean rise in temperature between immunization night and control night was 0.35°C (95% CI, 0.15 to 0.55). The increases in minimum temperature did not differ significantly between the normal and IUGR infants ( p = 0.11). Cortisol to creatinine ratios measured from overnight urine samples showed that 23 IUGR infants had consistently higher levels than 39 normal infants; control night medians 34 and 15 ( p = 0.01) and immunization night medians 56 and 26 ( p= 0.02), respectively. However, the percentage increase did not differ significantly between the IUGR infants and the normal infants. A smaller number of second immunizations were studied, but no significant differences were found.

Conclusion : These results suggest that although the impact of immunization is the same for IUGR and normal infants, because IUGR infants are less mature and at greater stress before immunization, the absolute levels that they experience after immunization are higher than those for normal infants.  相似文献   
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Epidemiological analyses of injury patterns and mechanisms help to identify the expertise military surgeons need in a combat setting and accordingly help to adjust infrastructure and training requirements. Therefore, a MEDLINE search (1949–2009), World Wide Web search (keywords “combat, casualties, war, military, wounded and neurosurgery”) and an analysis of deaths among allied war casualties in Afghanistan and Iraq were performed. Up to 10th December 2009 there had been 4,688 allied military deaths in Iraq and 1,538 in Afghanistan. Of these 22% died in non-hostile action, 33% in direct combat situations and the majority of 45% in indirect combat actions. The leading causes of injury were explosive devices (70%) and gunshot wounds. Chest or abdominal injuries (40%) and traumatic brain injuries (35%) were the main causes of death for soldiers killed in action. The case fatality rate in Iraq is approximately half that of the Vietnam War, whereas the killed-in-action rate in Afghanistan (18.7%) is similar to the Vietnam War (20%); however, the amputation rate is twice as high in modern conflicts. Approximately 8–15% of the fatal injuries seem to be potentially survivable. Military surgeons must have an excellent expertise in a wide variety of surgical specialties. Life saving emergency care, especially in the fields of thoracic, visceral and vascular surgery as well as practical skills in the fields of neurosurgery and oral and maxillofacial surgery are required. Additionally, it is of vital importance to ensure the availability of sufficient tactical and strategic medical evacuation capabilities for the wounded.  相似文献   
99.

Objective

To investigate the impact of intermittent interleukin‐2 (IL‐2) plus combination antiretroviral therapy (cART) on HIV‐1 entry co‐receptor use.

Methods

Primary HIV‐1 isolates were obtained from 54 HIV‐1‐positive individuals at baseline and after 12 months using co‐cultivation of peripheral blood mononuclear cells (PBMC) with activated PBMC of HIV‐negative healthy donors. HIV‐1 co‐receptor use was determined on U87‐CD4 cells.

Results

Fourteen out of the 21 (67%) IL‐2‐treated individuals harbouring a primary CCR5‐dependent (R5) HIV‐1 isolate at baseline confirmed an R5 virus isolation after 12 months in contrast to 3 out of 7 (43%) of those receiving cART only. After 12 months, only 1 R5X4 HIV‐1 isolate was obtained from 21 cART+IL‐2‐treated individuals infected with an R5 virus at entry (5%) vs. 2/7 (29%) patients receiving cART alone, as confirmed by a 5‐year follow‐up on some individuals.

Conclusions

Intermittent IL‐2 administration plus cART may prevent evolution towards CXCR4 usage in individuals infected with R5 HIV‐1.
  相似文献   
100.
目的对实验动物皮肤病原真菌2种培养方法进行了比较。方法将采集到的3只皮肤真菌感染病兔样品经由沙氏平皿法和沙氏试管斜面培养法分别进行培养。结果在3只真菌感染病兔中应用试管斜面法我们只检测到1例皮肤病原真菌阳性,而采用沙氏平皿法3例阳性全部检出。结论结合临床检测经验,我们认为本研究的沙氏平皿法优于沙氏试管斜面法,在实验动物皮肤病原真菌常规检测中具有推广应用价值。  相似文献   
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