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1.
目的:开发出新型号水痘疫苗保护剂替代现行含明胶、人血白蛋白疫苗保护剂,提高病毒保护效果及疫苗受种人群使用安全性。方法:(1)选取右旋糖酐、乳糖、甘露醇等辅料按不同配方进行制备疫苗保护剂。(2)使用不同配方制备的疫苗保护剂,应用细胞工厂水痘疫苗制备工艺进行生产水痘疫苗。(3)使用不同配方制备的疫苗保护剂生产的水痘疫苗与现行疫苗保护剂生产的水痘疫苗进行对比。结果:对比试验结果显示,使用右旋糖酐、乳糖、甘露醇等制备的疫苗保护剂,与现行疫苗保护剂比较无差异。结论:使用右旋糖酐、乳糖、甘露醇等制备的疫苗保护剂比较现行使用的疫苗保护剂,由于不含明胶及人血白蛋白,因此使该疫苗冻干保护剂的安全性、可靠性有所提高,并且疫苗冻干保护剂的成本将有所下降。  相似文献   

2.
明胶是水痘减毒活疫苗中常用的冻干赋形剂组分,是源于动物组织的大分子蛋白质。由于明胶可能引起疫苗接种后的不良反应,且与某些民族的宗教信仰相冲突,近年来WHO建议减少和避免明胶在病毒疫苗中的使用[1]。我国目前在疫苗冻干保护剂方面的研究与国外还有相当大的差距,明胶作为病毒性疫苗的冻干保护剂组分仍然广泛使用,但目前国内还没有相应的药用辅料标准,因此必须尽快建立相应的质量标准;同时还应对疫苗中明胶含量、分布情况、以及对病毒的稳定性研究和替代物等方面进行全面的研究,以便将来在疫苗生产中取消明胶的添加。本文主要对常规使用的冻干保护剂1和不含明胶的冻干保护剂2进行对比,以便筛选出更适合的水痘疫苗保护剂。  相似文献   

3.
冷冻干燥对重组酵母乙型肝炎疫苗效力(抗原性)的影响   总被引:5,自引:0,他引:5  
重组酵母乙型肝炎疫苗(酵母乙肝疫苗)加入保护剂后冷冻干燥,观察是否影响疫苗抗原性和稳定性。按5%和1%的比例,在酵母乙肝疫苗原液中分别加入蔗糖和明胶,低温冷冻干燥,制备3批冻干疫苗,分别进行体外相对效力和小鼠ED50测定。加保护剂冻干后酵母乙肝疫苗体外相对效力和小鼠ED50值较冻干前改变不大,而4℃放置和热加速后的稳定性均优于液体疫苗。因此现有酵母乙肝疫苗加入保护剂冻干后,显著提高了疫苗的稳定性,为进一步制备稳定的疫苗参考品打下了初步基础。  相似文献   

4.
病毒活疫苗冻干保护剂筛选研究   总被引:3,自引:2,他引:3  
为提高冻干病毒性活疫苗的成品滴度和稳定性及提高疫苗生产的出品率,本研究通过对多种保护剂成分如明胶、山梨醇、蔗糖、乳糖、右旋糖苷、精氨酸等及其配比的大量反复筛选试验,已初步选定了数种可供选择并进一步优化完善的冻干保护剂配方。与现行冻干保护剂相比,其疫苗出品率在相同投入下可提高三倍。  相似文献   

5.
麻疹疫苗生产连续培养多次收获工艺研究   总被引:1,自引:1,他引:0  
本研究对连续培养多次收获工艺用于麻疹疫苗生产的可行性、疫苗维持液保护剂、冻干保护剂及冻干过程等进行了大量反复试验,结果表明在现行条件下,本生产工艺具有重复性好、成本低、投入产出率高、易于质量控制等优势。对本工艺生产疫苗进行全面检定,表明成品滴度和稳定性试验指标等均高于90版《生物制品规程》要求,并在试验基础上制定出了生产工艺流程。  相似文献   

6.
冻干甲型肝炎减毒活疫苗的研制   总被引:3,自引:0,他引:3  
研制冻干甲肝减毒活疫苗,提高疫苗的稳定性,便于保存及运输,保证疫苗的接种效果.采用CA-9冻干保护剂,按13.5的比例加入疫苗,制备冻干疫苗.冻干甲肝减毒活疫苗具有与液体疫苗相同的安全性及免疫原性.在2~8℃保存的有效期较液体疫苗的3~5个月提高到18个月.在室温和37℃保存的稳定性也明显提高.冻干甲肝减毒活疫苗的稳定性良好,无需低温保存、冷链运输,便于甲肝疫苗的大规模推广应用.  相似文献   

7.
卤虫脱壳卵的液氮冷冻保存研究   总被引:4,自引:0,他引:4  
作者以甘油、DMSO、葡萄糖和蔗糖为冷冻保护剂对卤虫脱壳卵进行了液氮冷冻保存研究.各保护剂对短期吸水发育的胚胎有一定的冷冻保护作用,在本实验条件范围内,高浓度保护剂较低浓度保护剂好,双重保护剂(甘油+DMSO、葡萄糖+蔗糖)冷冻保护作用较单一保护剂效果好。饱和NaCl溶液对各发育时期的胚胎均有较好的冷冻保护作用,但对后期胚胎的冷冻保护作用较弱。作者认为胚胎内冰晶的形成是卤虫脱壳卵冷冻致死的主要原因。冷冻保护剂对卤虫脱壳卵的冷冻保护作用可能与它们的脱水作用有关。  相似文献   

8.
200多年来,疫苗研究取得了巨大发展.至今,仪用于人类疾病预防控制的疫苗就有30多种.中国是疫苗生产大国,多数人用疫苗均能自主生产.疫苗的广泛应用在预防和控制严重危害人类健康疾病方面发挥了重要作用.然而,至今仍有许多重要疫苗未能研制成功,特别是一些严重危害人类健康的病毒的疫苗需要加大研发力度;  相似文献   

9.
冷冻干燥技术广泛应用于细菌性活疫苗生产和菌种保藏等方面。细菌细胞在冷冻干燥过程中会出现损伤,甚至死亡。通过添加适合的冻干保护剂可以最大程度减小细胞损伤,保持活菌制剂的活力和性能。就冻干过程对细菌的损伤机制、冻干保护剂的作用机理以及保护剂的筛选方法等方面进行了阐述,对活菌制剂保护剂的筛选有所启示。  相似文献   

10.
口蹄疫(FMD)是一种严重威胁畜牧业发展的重要传染病,目前世界上许多国家和地区都有该病的流行与发生.其控制措施主要是疫苗免疫,虽然传统疫苗在该病的防控中起了重要的作用,但也存在着诸多的缺点.因此研制新型的FMD疫苗是今后的发展方向.本文结合实验室在FMD新型疫苗研究方面所开展的探索性研究工作,综述了国内外在FMD基因工程弱毒苗或灭活苗、蛋白质和合成肽疫苗、空衣壳疫苗、细胞因子增强型疫苗等研究领域所取得的进展.  相似文献   

11.
魏东  全元  王辰星  付晓  周政达  王毅  高雅  吴钢 《生态学报》2014,34(11):2821-2829
随着我国煤电基地建设进程的不断加快,煤电基地建设与开发活动引起的环境问题也日趋严重。了解生态环境质量现状,评估其对生态系统与人民健康水平的影响,制定合理的保护、治理、恢复策略是煤电基地环境保护工作的重中之重,而生态环境监测是解决上述问题的基础。然而,现有的监测技术体系普遍存在自动化水平较低、成本较高、时空覆盖面较低等问题。鉴于物联网技术在提高信息采集效率和改善信息获取方式方面的作用日益显著,所以将物联网技术应用于煤电基地生态环境监测,从感知层、传输层、支撑层、应用层、用户层的角度明确生态环境监测技术体系,为解决上述问题提供有效途径。  相似文献   

12.
林有润 《植物研究》2002,22(3):341-365
棕榈科原省藤亚科因其子房壁及外果皮被倒生、螺旋状排列的鳞片所覆盖,而区别于其他亚科,因而独立分出成一新科--省藤科。作者讨论了棕榈科的祖先种可能在石炭纪时,自原始裸子植物开以顿目在分化、衍生出苏铁目祖先种的进化干上,于白垩纪时分化出的一个分支。在棕榈科的祖先种出现不久后,在其进化的分支上,于白垩纪后期又分化出一旁支,成为棕榈科的姊妹科--省藤科的祖先种。从两祖先种分别再分化、衍生出现今分布地球上该二科的属与种。两科、尤其前者是被子植物、尤其是单子叶植物中最原始的类群之一。作者还提出棕榈科象牙椰亚科与贝叶棕亚科是该科最原始或较原始的两类群;槟榔亚科和腊材榈亚科是较进化的两类群;而水椰亚科祖先种可能源于象牙椰亚科的祖先种,但又演化为该科最进化与特化的类群。省藤科省藤亚科略比鳞果榈亚科原始。作者讨论了两科为泛热带分布的科,指出两科的"现代分布区"在南北两半球热带地区,少数种还延伸分布到两半球暖亚热带、甚至达中亚热带地区,分布区边缘最北达日本中部、中国长江流域及黄河下游的南部,美国加利佛尼亚州与佛罗里达州和地中海北部;最南达智利中部和新西兰南部;而"现代分布中心"在热带与暖亚热带的亚洲,中、南美洲,大洋洲及非洲的东、南、西部;但分布区的"密集中心"则在热带亚洲、热带中及南美洲、南太平洋群岛及非洲东南部。作者还介绍了近50年我国南方引种驯化成功的两科植物近400种(见*图谱),其中少数为耐寒的种类,有的种已引种到长江流域或更北的地区。引种的大部分种都有其重要的经济用途,包括:1. 食用,如淀粉和树液可制"西米"或制糖,酿酒、醋或作饮料;果或种子榨油,供食用或工业用;某些种的嫩芽作蔬菜,甚至种子代咖啡饮用;2. 药用,有消炎、止血、活血、驱虫、抗癌等用;3. 建筑、工艺与日用品,包括不少种的树干供建普通房子、桥梁、小船;少数种可提制工业用蜡;许多种的纤维制高级缆绳和编织品;还制工艺品与日用品等;4. 代表热带景观的园林工程、绿化及美化环境的观赏树和人行道树及建造园林景观生态类型的树种等。  相似文献   

13.
陈妍  周妍  包岩峰  周旭  苏香燕 《生态学报》2023,43(21):8894-8902
我国实施了诸多生态保护修复工程,取得了显著成效。然而,以往工程多以湿地、森林、草原等单一类型的生态系统为保护修复目标,缺乏区域整体性、系统性考虑。2016年以来,我国开始从完整流域的视角出发,系统考虑生态系统完整性、自然地理单元连续性和社会经济可持续性,实施山水林田湖草沙一体化保护和修复工程。该类工程保护修复目标多样、内容庞杂,因而成效评估面临子项目类型多、空间尺度多、目标维度多、项目实施周期短等诸多挑战。就空间尺度而言,评估对象既要涵盖常规评估中相对较大的、确定的空间范围,也要涵盖具有相对类似生态问题或目标的保护修复单元,以及实际采取措施的子项目;就时间尺度而言,既要考虑工程实施结束时的成效,也要考虑实施结束后的成效动态;就评估内容而言,既要关注社会、生态、经济效益,也要考察工程措施与生态效应之间的关系、不同类型子项目的关联性与协同性、工程的整体性与系统性。研究基于上述背景制定了一个新型评估框架,重点强调基于子项目、保护修复单元以及工程范围三个尺度的指标体系,以及生态、社会、经济、管理四个方面的评估内容。新的评估框架将有助于完善山水林田湖草沙一体化保护和修复工程标准体系,为推进国土空...  相似文献   

14.
将小叶杨分别与其他11个树种枯落叶粉碎混合后进行室内分解培养,分析不同树种枯落叶混合分解对土壤性质的影响及其相互作用.结果表明:12个树种枯落叶单独混土分解均明显提高了土壤脲酶、脱氢酶、磷酸酶活性和有机质、碱解N含量,但对土壤速效P含量和土壤阳离子交换量(CEC)的影响差异较大,其中柠条和紫穗槐枯落叶改善土壤性质的效果明显.小叶杨分别与油松、侧柏、刺槐、白榆枯落叶混合分解,对土壤微生物数量的影响存在相互促进作用;小叶杨分别与侧柏、柠条枯落叶混合分解对土壤有机质、速效P、速效K含量和CEC的影响存在相互促进作用,但对土壤大部分酶活性的影响却存在相互抑制作用;小叶杨与落叶松枯落叶混合分解对土壤多数酶活性和养分含量的影响存在相互促进作用,而与樟子松枯落叶混合分解时则有抑制作用.总体上,小叶杨分别与白榆、油松、落叶松和刺槐枯落叶混合分解可促进土壤性质的改善,而与侧柏、柠条、樟子松、沙棘和紫穗槐枯落叶混合分解时则相互抑制.  相似文献   

15.
Mt. Wuyi, located at 27°37‛-27°54‛ N, 117°27‛-117°51‛ E, is the highest mountain in South-East China. Its main peak, Huanggangshan, is 2158 m above the sea level. In 1955, P. C. Chen organized the first expedition to Mt. Wuyi, and the authors investigated the different ravines and the forests of that area in 1976 and from 1979 to 1984 respectively. Up to now 355 species of the bryophytes have been found in Mt. Wuyi. I. The influence of the factors of geological history on the bryoflora of Mt. Wuyi Fujian Province, belonging to Cathaysian, one of three Chinese ancient lands, was a part of ocean until the end of the lower Tertiary. In the early Devonian, Fujian uplifted above the sea level, but it submerged in the sea later, and then uplifted above the sea level again in the upper Triassic. By the end of the lower Triassic the Himalayan movement influenced the paleogeography of China deeply, and the eastern and central mountains of Fujian uplifted again. In the Tertiary, Fujian was influenced by the hot maritime weather, so the tropical evergreen forests existed in southern Fujian at that time. The conclusion was made by Z. B. Zhao in 1983 after his long period of study on geological history of Fujian Province since the Yanshan movement. According to the morden geographical distribution of Chinese bryophytes, it seems that the above influence might be related to the bryophytes of Mt. Wuyi and also the southern part of Zhejian Province. By the end of the Tertiary the weather became cold in most parts of China. Since then the cold weather and hot weather alternated several times. One kind of the endemic elements of the bryoflora formed in the area from the south-eastern coast of China to the southeastern Xizang (Tibet), including Japan. They are not specialized at the family level or closely related to each other, but they have similar distribution and belong to different families. In the Quaternary, Mt. Wuyi gradually uplifted following the Himalayan movement. As the weather cooled down in the upper part of the mountain, deciduous broad-leaved and needleleaved trees increased there. Meanwhile, temperate genera and species of the bryophytes spread and invaded South China and entered Mr. Wuyi. Rhytidiadelphus and Hvlocomium probably began to grow in Mt. Wuyi at that time, and their distribution is quite different from their primary one. On the other hand, a part of tropical and subtropical bryophytes might enjoy the changed weather and environment in the Quaternary and existed in a few small localities of Mt. Wuyi, and the genera Haplomitrium, Endotrichella and Floribundaria are probably their representatives. From the point of view of geological history we are now living in the interglacial period and the present natural conditions will last continuously, so they will steadily influence the bryoflora of Mt. Wuyi in a long period of time. 2. Essential characteristics of the bryoflora in Mt. Wuyi Due to the geographical position and the other factors of Mt. Wuyi the bryoflora is represented by numerous tropical and subtropical elements (34.1%), but the East-Asiatic endemic ones (79.2%) are characteristic of the bryoflora in Mt. Wuyi (Tab. 1). The tropical and subtropical families of the bryophytes, found south of Changjiang (Yangtzi) River, are Haplomitriaceae (1 genus, 3 species), Porellaceae (2 genera, 8 species), Frullaniaceae (2 genera, 10 species), Lejeun eaceae (21 genera, 35 species), Trachypodaceae (3 genera, 4 species), Meteoriaceae (10 genera, 17 species), Neckeraceae (5 genera, 8 species) and Hookeriaceae (3 genera, 3 species). The above 8 families, including 46 genera and 85 species, represent about 1/4 genera (24.3%) and less than 1/4 species (23.9%) of the bryoflora of Mt. Wuyi. Most species of East-Asiatic elements show very close relationships with Japan, and are widely distributed from the low altitude of Mt. Wuyi to the summit of Mt. Huanggangshan. However, the Holarctic species (26.8%) are also important elements of the bryoflora in Mt. Wuyi, showing its transition nature, although it is located in the subtropics. Moreover, the in fluence of the Himalayas also exists in Mt. Wuyi, and the Himalayan elements cover 14.4% in the bryoflora of Mt. Wuyi. The similarity coefficients between the bryofloras of Central and South America, Africa and Oceania and that of Mt. Wuyi are from 5.0-9.2% respectively. The endemic species are not very many and cosmopolitan species are only 7 there. In 1958, P. C. Chen designated Mt. Wuyi as “the transition region of South and North China rich in East-Asiatic genera and species”. His very important conclusion is essentially in accordance with the fact of the bryoflora on Mt. Wuyi. Recently, some of the new records fur ther show the characteristics of the bryoflora in Wuyi. Two facts are worth being mentioned. One is that East-Asiatic genera are only five in Mt. Wuyi. However, there are 9 East-Asiatic genera in Mt. Huangshan more than in Mt. Wuyi; 4 East-Asiatic genera are recorded in Mt. Shennongjia. The other is that epiphyllous liverworts in Mt. Wuyi, consisting of 7 families, 21 genera and 36 species, are less than on Hainan Island and Xishuangbannan, located in the tro pics in China. 3. Comparison between the bryoflora of Mt. Wuyi and those of the neighbouring regions As China covers a very large area, bryofloristic elements are quite different in the diffe rent regions. In this section, we are concentrated on making a comparison between the bryof loras of Mt. Wuyi and the regions belonging to the Central China of the bryoflora named by P. C. Chen. Huaping Forest Region, Guangxi Zhuang Autonomous Region in South China, with both latitute and altitude very similar to Mt. Wuyi, is included in this comparison (Fig. 1). According to the rough estimation, the similarity coefficient of moss genera between Mt. Wuyi and Huaping is 56.3%, and those between the mountain and southern Zhejian and Mt. Huangshan, Anhui, are 62.7% and 51.6% respectively, while the similarity coefficient of the genera of the mossfloras between Mt. Shennongjia and Mt. Wuyi is 46.8%. Table 2 shows the statistics of mosses in Mt. Wuyi and the others, but the bryoflora of Huaping needs further study However, it is very interesting to note that Haplomitrium and Pleurozia of liverworts are both found in Mt. Wuyi and Huaping Forest Region, and the similarity coefficient between the mossfloras of Mt. Wuyi and Zhejian Province is also higher than those mentioned above. Tropical and subtropical elements reduce towards the north in China, and temperate ones increase. Huaping is located in the south, and, as expected, some tropical and subtropical genera such as Hookeriopsis and Symphyodon have been found there, but not in Mt. Wuyi; several temperate genera, such as Schwetschkeopsis and Fauriella, have been recorded in Mt. Huangshan, but not in Mt. Wuyi. For some unknown reasons, Octoblepharum and Neckeropsis are only found in southern Zhejiang, but not in Mt. Wuyi. Mt. Shennongjia, with its main peak over 1000 m higher than that of Mt. Wuyi, is located in its northwest, and more than ten temperate genera, such as, Ceratodon, Aulacomnium Myurella, Bryonoguchia and Abietinella have been found there. Generally, Mt. Wuyi belongs to the central subtropical region of China, and East-Asiatic endemic genera are the main elements of its bryoflora, but the bryoflora also consists of tropical and subtropical elements with some temperate ones. 4. East-Asiatic endemic genera in the bryoflora of Mt. Wuyi In the bryoflora of Mt. Wuyi, one of the main elements, East-Asiatic endemic genera, should not be neglected (Tab. 4). East-Asiatic endemic genera in Mt. Wuyi (five) are less than in Mt. Huangshan and Mt. West Tianmu, although the positions of the latter two are very close to Mt. Wuyi. East-Asiatic endemic genera of liverworts are Trichocolea and Macvicaria so far found in Mt. Wuyi, and the mosses are Myuriopsis, Meteoriella, Pseudospiridentopsis (Fig. 1). Myuriopsis is only distributed in Taiwan Province and Mt. Wuyi, and the other four are distributed in Mt. Huangshan or Mt. West Tianmu, and also in Taiwan, besides in Mt. Wuyi. About thirty EastAsiatic endemic genera have so far been known in China, which means that about one sixth of East- Asiatic endemic genera of the bryophytes occur in Mt. Wuyi. We may notice that nine and seven East-Asiatic endemic genera of the bryophytes have been recorded in Mt. Huangshan and Mt. West Tianmu respectively. In Mt. Shennongjia, Central China, there are four East Asiatic endemic genera, but only two have been found in the Huaping Forest Region, South China. In Mt. Dinghua, located south of Mt. Wuyi, on East-Asiatic endemic genus of the bryophytes has so far been found. East-Asiatic endemic genera of the bryophytes are mainly limited to China, Korea and Japan, including the East Himalayas, rarely occur in South Asia, Siberia of the Soviet Union. Therefore, these genera enjoy a warm and moist environment. In Mt. Wuyi, all the East-Asiatic endemic genera are monotypic ones with a disjunct distribution. Now in Taiwan Province five of six recorded East-Asiatic endemic genera are common to Mt. Wuyi. In Japan, about eleven, i.e. one third of, East Asiatic endemic genera so far found are common to China, which shows a long history of the phytogeographical relationships between Japan and China. East Asiatic endemic genera of the bryophytes might therefore exist on islands of Taiwan Province and Japan before they were separated from the mainland of Asia. However the fossil evidence is still lacking in the bryophytes, so we are not able to discuss about the distribution area and the distribution center of the East-Asiatic bryoflora in detail. The above estimation is more or less related to geological history, and we assume that the East-Asiatic endemic genera have existed at least since the end of the Tertiary. Starting from the Quaternary, the climatic change during glacial epoch has been possibly the most important factor affecting the bryoflora in Asia, and the upheaval of the Himalayas has stimulated the diversity and the specialization of the bryophy tes. Considering these factors, East-Asiatic endemic genera might be the “Tertiary fossil plants”. Another problem is difficult to explain, because Mts. Huangshan, West Tianmu and Shen nongjia were once influenced by glaciation directly, although Chinese geologists hold different views. However, no evidence of glaciation has been found in Mt. Wuyi. It is worth to study the close relationships between Mt. Wuyi, Mt. Huangshan and Mt. West Tianmu, where is the distri bution center of the East-Asiatic endemic genera. The above three mountain regions share half of the East-Asiatic endemic genera, and about 32% genera of the others are found in two of them (Fig. 2). Myuriopsis, one of the East Asiatic types, was only recorded in Taiwan Pro vince, Japan and Korea. Neodolichomitra, occuring in Taiwan Province, is endemic to China. More or less the differentiation has taken place in Mt. Huangshan, Mt. West Tianmu and Mt. Wuyi. The number of the East-Asiatic endemic genera is smaller in Mt. Wuyi, so it is possibly located on the border of the distributional center of the East-Asiatic endemic genera. Moreo ver, three of four East-Asiatic endemic genera in Mt. Shennongjia are also found in Mt. Huang shan and Mt. West Tianmu, but the other East-Asiatic genus in Mt. Wuyi is common to the mountain areas in SW China, the Qinglin Range of NW China, and the isolated mountain areas of NE China. Considering all the characteristics of the bryoflora of Mt. Shennongjia, we assume that Mt. Shennongjia may belong to another distribution center, including SW part of Sichuan Province, and the other neighbouring mountains.  相似文献   

16.
Stress activates the central and peripheral components of the stress system, i.e., the hypothalamic-pituitary-adrenal (HPA) axis and the arousal/sympathetic system. The principal effectors of the stress system are corticotropin-releasing hormone (CRH), arginine vasopressin, the proopiomelanocortin-derived peptides alpha-melanocyte-stimulating hormone and beta-endorphin, the glucocorticoids, and the catecholamines norepinephrine and epinephrine. Appropriate responsiveness of the stress system to stressors is a crucial prerequisite for a sense of well-being, adequate performance of tasks and positive social interactions. By contrast, inappropriate responsiveness of the stress system may impair growth and development, and may account for a number of endocrine, metabolic, autoimmune and psychiatric disorders. The development and severity of these conditions primarily depend on the genetic vulnerability of the individual, the exposure to adverse environmental factors and the timing of the stressful event(s), given that prenatal life, infancy, childhood and adolescence are critical periods characterized by increased vulnerability to stressors. The developing brain undergoes rapid growth and is characterized by high turnover of neuronal connections during the prenatal and early postnatal life. These processes and, hence, brain plasticity, slow down during childhood and puberty, and plateau in young adulthood. Hormonal actions in early life, and to a much lesser extent later, can be organizational, i.e., can have effects that last for long periods of time, often for the entire life of the individual. Hormones of the stress system and sex steroids have such effects, which influence the behavior and certain physiologic functions of individuals for life. Exposure of the developing brain to severe and/or prolonged stress may result in hyperactivity/hyperreactivity of the stress system, with resultant amygdala hyperfunction (fear reaction), decreased activity of the hippocampus (defective glucocorticoid-negative feedback, cognition), and the mesocorticolimbic dopaminergic system (dysthymia, novelty-seeking, addictive behaviors), hyperactivation of the HPA axis (hypercortisolism), suppression of reproductive, growth, thyroid and immune functions, and changes in pain perception. These changes may be accompanied by abnormal childhood, adolescent and adult behaviors, including excessive fear ('inhibited child syndrome') and addictive behaviors, dysthymia and/or depression, and gradual development of components of the metabolic syndrome X, including visceral obesity and essential hypertension. Prenatal stress exerted during the period of sexual differentiation may be accompanied by impairment of this process with behavioral and/or somatic sequelae. The vulnerability of individuals to develop varying degrees and/or components of the above life-long syndrome is defined by as yet unidentified genetic factors, which account for up to 60% of the variance. CRH has marked kindling and glucocorticoids have strong consolidating properties, hence both of these hormones are crucial in development and can alone produce the above syndrome. CRH and glucocorticoids may act in synergy, as in acoustic startle, while glucocorticoids may suppress or stimulate CRH, as in the hypothalamus and amygdala, respectively. A CRH type 1 receptor antagonist, antalarmin, inhibits both the development and expression of conditioned fear in rats, and has anxiolytic properties in monkeys. Profound stressors, such as those from sexual abuse, may elicit the syndrome in older children, adolescents and adults. Most frequently, chronic dysthymia and/or depression may develop in association with gastrointestinal complaints and/or the premenstrual tension syndrome. A lesser proportion of individuals may develop the classic posttraumatic stress disorder, which is characterized by hypocortisolism and intrusive and avoidance symptoms; in younger individuals it may present as dissociative personality disorder.  相似文献   

17.
Biophysicochemical approaches to the solution of nanotechnology problems associated with the design of functional biomimetic nanosystems, hybrid and composite nanobiomaterials and study of their structure-function relationships. The results of studies concerned with physicochemical mechanisms of the formation of organized biomimetic nanostructures and bioinorganic nanomaterials in systems involving a bulky liquid phase and the interface (gas-liquid, solid-liquid, liquid-liquid)during the synthesis and structure formation with the participation of the components of colloid systems, inorganic nanoparticles of various composition and clusters of metals, surfactants, polyelectrolytes and their complexes are discussed. In the development of the methods for the formation of composite bioinorganic nanosystems containing inorganic nanocomponents, two major approaches were used: adsorption and incorporation into the biomolecular matrix or colloid system of presynthesized inorganic nanoparticles, as well as the synthesis of the inorganic nanophase immediately in the biomolecular system. The methods of obtaining biomaterials and nanosystems are based on the principles of biomimetics, biomineralization, self-assembly and self-organization, combination and integration of a number of synthetic and physicochemical methods (physical and chemical adsorption, Langmuir technique, the formation of polycomplexes, chemical linking, competitive interactions, and substitution of ligands in supramolecular and coordination complexes) and nanocomponents of different nature. In particular, a novel approach to the preparation of highly organized nanofilm materials was developed, which is based on the effect of self-assembly and self-organization of colloid nanoparticles during the formation of their complexes with polyfunctional biogenic ligands in the volume of the liquid phase in the absence of any surfaces and interfaces. The physical and chemical factors responsible for the formation of structurally ordered biomolecular and composite nanosystems including nano-sized components of different nature and the possibilities to control the composition, structure, and properties of resulting nanomaterials and nanosystems are discussed. The experimental methods and approaches developed may be useful in studies of structure-property relationships and basic mechanisms of structural organization and transformation at the nanoscales level in biological, artificial, and hybrid nanosystems. The problems of practical application of the synthetic methods and the corresponding nanomaterials are discussed.  相似文献   

18.
19.
 本文研究了广西龙胜县里骆林区、宜山县庆远林区、岑溪县七坪林区和田林县老山林区四种不同生态地理区域杉木人工林土壤微生物及其生化活性。研究结果表明:1.土壤微生物的总数及各类群数量均以龙胜县里骆林区和田林县老山林区杉木人工林土壤最高,岑溪县七坪林区次之,宜山县庆远林区最低。2.土壤生化活性包括土壤氮的转化强度,土壤碳的氧化代谢能力和土壤酶活性,也均以龙胜县里骆林区和田林县老山林区杉木人工林土壤最强,岑溪县七坪林区次之,宜山县庆远林区最弱。3.四种不同生态地理区域杉木人工林生长状况与土壤微生物的数量分布和生化活性表现相似规律,龙胜县里骆林区和田林县老山林区杉木人工林林木生长最好,岑溪县七坪林区次之,宜山县庆远林区最差。  相似文献   

20.
Abstract. Characters of the head of adephagan larvae were examined and analysed phylogenetically. A labrum which is completely fused to the clypeofrons and the presence of a closed prepharyngeal tube are autapomorphies of Adephaga. Partial reduction of the fossa maxillaris, cardo and stipes forming a functional unit, the immobilization of the lacinia, attachment of M. craniolacinialis to the lateral stipital wall, and loss of one stipitopalpal muscle, are considered autapomorphies of Adephaga excluding Gyrinidae. Complete reduction of the fossa maxillaris and the presence of M. craniostipitalis medialis are possible autapomorphies of Adephaga excluding Gyrinidae and Haliplidae. The presence of caudal tentorial arms, insertion of the galea on the mesal side of palpomere I, and absence of the lacinia are considered synapomorphies of Trachypachidae and Dytiscoidea (Noteridae, Amphizoidae, Hygrobiidae, Dytiscidae). The presence of a slender, elongated process of the head capsule, which articulates with a corresponding socket of the cardo, is a possible autapomorphy of Dytiscoidea. The sinuate frontal sutures, distinctly protruding prementum, shortened M. craniostipitalis medialis, and absence of M. submentopraementalis are considered autapomorphies of Geadephaga excluding Trachypachidae. The presence of a regular row of hairs along the anterior hypopharyngeal margin is a possible autapomorphy of Geadephaga excluding Trachypachidae and Rhysodidae. Improvement of the hypopharyngeal filter apparatus suggests the monophyly of Anisochaeta. Presence of a penicillum and partial reduction of the lacinia are possible autapomorphies of Anisochaeta excluding Omophronini. Larvae of Cychrini, Carabini, Nebriini and Notiophilini are characterized by a strongly developed, cone-shaped hypodon. Postocular and cervical ridges, crosswise arrangement of antennal muscles, and a completely flattened hypopharynx are considered autapomorphies of Caraboidea Limbata.  相似文献   

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