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来自不同疟疾疫区——长沙、上海、郑州、武汉四地区的中华按蚊,分别以羊膜饲血法感染湖南慈利或湖北沔阳两地区的间日疟原虫,交叉对比其易感性。七次实验共解剖饲血蚊541只。实验结果显示:以腺感染率和阳性腺指数为主要指标,四地区中华按蚊对间日疟原虫的易感性基本相似:两地区间日疟原虫对中华按蚊的感染力也大致相同。并讨论了可能影响人工感染率的几个因素。 相似文献
13.
An ancient femal corpse excavated from the robbed tomb No. 1 at Guo-Jia-Gang in Jingmen city of Hubei Province was studied. It was confirmed that the corpse was buried more than 2 300 years ago, namely at the middle stage of the Warring States period and is the earliest one of the ancient coffin corpses unearthed in China sofar. It is of the same type as the ancient corpses of Weatern Han Dynasty excavated from tomb No. 1 at Ma-Wang-Dui in Changsha City and from the tomb No. 168 at Phoenix Hill in Jinagling City respectively. The collagenous fibers of connective tissue from all parts in the corpse were well preserved, showing fine ultrastructure with clear periodical cross banding, and a lot of bacterial spores were found between them. In addition, a large number of eggs ofclonorchis sinensis andtrichuris trichiura were found in the content of the bowel. The level and the cause of good preservation were discussed and it was believed that the good preservation may resulte from the combined effect of the internal and external environmental factors around the corpse. 相似文献
14.
采用80℃热水提取,得到当归水溶性多糖W-ASP。经阴离子交换柱层析、凝胶过滤柱层析对其进行纯化分级。实验结果表明:W-ASP11主要由葡萄糖组成,相对分子质量约为380000;W-ASP12主要由半乳糖和阿拉伯糖组成,相对分子质量约为19000;W-ASP2和W-ASP3主要舍半乳糖、阿拉伯糖和鼠李糖以及少量葡萄糖和甘露糖,并含有较高的糖醛酸,由单糖组成及红外图谱初步分析,可判断是一种果胶类多糖。当归多糖主要组分W-ASP3经凝胶色谱(GPC)鉴定为均一组分,其相对分子质量约为62000。 相似文献
15.
本文首次报告了我国脉毛蚊属、库蚊属和按蚊属10种蚊Ⅳ龄幼虫颏的光镜与扫描电镜的形态特征。结果表明,利用颏进行分类鉴定,在某些种类具有一定的意义。 相似文献
16.
目的 了解自然状态下猫感染华支睾吸虫的现状及该病对肝脏/胆管及生理生化指标的影响。方法 观察活猫的精神状态,处死后肝脏形态及切开后的眼观形态;通过病理切片观察肝脏、胆管及胆囊的病理变化;测定血常规及肝脏功能指标。结果 7.3%的肝脏(8/218,218为阳性猫)表面有明显的黄豆粒大小的肿瘤;94%(205/218)的肝脏质地变硬,结缔组织增生;29.8%(25/218)肝脓肿,肝色较黄,小叶结构模糊:54.1%(118/218)胆管内上皮细胞增生,淋巴细胞浸润;感染猫血红细胞显著降低(P〈0.01),血清丙氨酸氨基转移酶显著升高(P〈0.05)。结论 华支睾吸虫对肝脏、胆管及胆囊造成了严重伤害,很可能是肝癌、胆管癌的诱因之一。 相似文献
17.
A cytoskeletal actin gene in the mosquito Anopheles gambiae 总被引:2,自引:0,他引:2
C. E. Salazar D. Mills Hamm D. M. Wesson C. B. Beard V. Kumar F. H. Collins 《Insect molecular biology》1994,3(1):1-13
Five actin genes have been identified in the mosquito Anopheles gambiae , and a constitutively expressed actin gene has been chosen for detailed analysis. We have physically mapped and sequenced this gene and six associated cDNAs, including translated coding regions, as well as the 5 and 3 flanking sequences. Analysis of stage-specific RNA shows this gene to be present in all stages of mosquito development and in an established A. gambiae cell line, thus indicating a cytoskeietal actin. In the sequence of the translated coding region and in pattern of expression, this gene is very similar to the cytoskeietal actin genes of Droso-phila melanogaster , and in sequence, equally similar to the Artemia cytoskeietal actin gene 403 (99.2% identity among the three amino acid sequences). Sequencing of this A. gambiae actin gene (designated actWior its location in chromosome division 1D) and selected cDNAs shows that it possesses three alternative leader sequences; thus the gene appears to have three alternative promoters. These promoters should ultimately prove useful in the production of transgenic constructs for constitutive expression. 相似文献
18.
武进县连续14年中华按蚊消长调查得到:其密度每年以11.47%的速度递减;在总蚊中的构成比每年以8.09%的速度递减;消长曲线与旬平均温度呈直线正相关,r=0.8087(P<0.05),其回归方程为y=19.8549+2.9497x;畜棚内密度显著高于住房,t’=4.4021(p<0.001) 相似文献
19.
1900年夏,在扬州市郊,利用特建的实验小屋,以牛为引诱动物,进行了凯素灵胶悬剂浸泡蚊帐对侵入室内蚊虫毒杀和兴奋驱避作用的研究。按40mg ai/m~2处理1~84天后,结果表明对中华按蚊和三带喙库蚊均有较好的毒杀作用。毒杀作用下降主要表现在对外逃蚊虫上,而对留存在室内的蚊虫,毒杀效果持久、稳定,试验期间,留存室内的中华按蚊的死亡率均达80%以上,结果优于三带喙库蚊和同等剂量的溴氰菊酯乳剂。结果还表明,侵入处理小屋蚊虫数比对照小屋减少,窗阱外逃率大大高于对照小屋,说明凯素灵胶悬剂浸泡蚊帐,对蚊虫具有兴奋驱避作用。 相似文献
20.
P. Carnevale P. Guibert S. Manguin 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2010,104(7):484-489
The purpose of our entomological survey was to estimate mosquito biodiversity, infectivity rates and insecticide resistance levels in Anopheles species in four study sites in a mining area with high malaria transmission in southeastern Guinea. Anopheles gambiae s.l. (77%) was the most common Anopheles collected followed by An. funestus (20%). The specimens of the An. gambiae complex were predominantly An. gambiae S form (97.6%) with 1.4% of An. gambiae M form found in Kérouané only, and 1% of An. arabiensis which was present in all four study sites. Anopheles gambiae S form and An. funestus were found to be infected with Plasmodium falciparum, with infectivity rates of 4.1% and 4.4% and inoculation rates of 0.60 and 0.19 infected bite/person/night, respectively. In addition, a high level (79%) of the knockdown resistance (kdr) L1014F mutation was reported in the populations of An. gambiae S form. The high malaria transmission that occurs in the prospected area of Guinea requires a long-term vector control programme. However, such a control programme will have to consider the presence of the kdr gene at a surprisingly high level within the dominant vector, which could reduce the expected impact of vector control. 相似文献