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1.
西双版纳热带雨林蚁科昆虫区系分析   总被引:9,自引:1,他引:8  
徐正会 《动物学研究》1999,20(5):379-384
在西双版纳热带雨林已鉴定蚊科昆虫9亚科76属267种。西双版纳地区的蚂蚁区系以热带至亚热带分布的东洋界成分最为丰富。在属级水平上,与马来西亚界关系最为密切。与澳洲界关系较密切;与非洲界和马拉加西界的关系知中。与新北界,新热带界和古北界的关系最为疏远。可见西双版纳的蚂蚁区系具有典型的热带亚洲起源特征,同时与澳洲和非洲的热带区系有一定的渊源关系。  相似文献   

2.
Trifluoperazine inhibits the activation of phosphodiesterase by binding to the calcium-dependent activator. To determine further the specificity by which trifluoperazine binds to activator, we compared the binding of trifluoperazine to activator prepared from several species and tissues and to a number of other calcium-binding proteins devoid of activator activity.Trifluoperazine binds to activator prepared from human, bovine, rat and rabbit brain and from chick embryo fibroblasts. In each case, the binding of trifluoperazine to activator was qualitatively similar and related quantitatively to the ability of the preparation to activate phosphodiesterase.Of the other calcium-binding proteins examined, namely, troponin-C, S-100 protein, phospholipase A, phospholipase B and myosin light chain, only troponin-C displayed any significant calcium-specific binding of trifluoperazine. The binding to troponin-C, however, appeared to be different from the binding to activator; whereas the binding of trifluoperazine to actovator showed no cooperativity, the binding to troponin-C showed positive cooperatively.These results and earlier data showing that trifluoperazine fails to bind to a variety of other proteins, indicate that the binding of trifluoperazine to the calcium-dependent activator of phosphodiesterase is selective and suggest that this binding may explain some of the biochemical and pharmacological actions of this antipsychotic agent.  相似文献   

3.
Complexes between Escherichia coli RNA polymerase and bacteriophage S13 and phage phiX174 replicative form III DNAs have been shown to form at specific locations on the phage genomes. The major locations on S13 have been mapped at 8 to 10 and 92 to 96% of the genome length, starting from the unique Pst I cleavage site. The locations correspond to the beginnings of genes D and B, respectively. Four minor locations map at 18 to 22, 28 to 32, 50 to 56, and 70 to 74% of the genome. The 70 to 74% site corresponds to the beginning of the A gene. The major locations on phiX174 are at 8 to 10, 50 to 54, and 92 to 94% of the genome. The 50 to 54% site is at the start of the H gene and has an equivalent minor site on S13, but it is not a promoter site. Three minor sites on phiX174, at 20 to 24, 26 to 32, and 68 to 74% of the genome, correspond to sites on S13. The data confirm the locations of sites identified by restriction fragment binding experiments (E. Rassart and J. H. Spencer, J. Virol. 27:677--687, 1978) and the assignment of putative promoters at the start of genes A, B and D.  相似文献   

4.
Nuclear factor kappaB (NF-kappaB) plays a pivotal role in numerous cellular processes, including stress response, inflammation, and protection from apoptosis. Therefore, the activity of NF-kappaB needs to be tightly regulated. We have previously identified a novel gene, named CIKS (connection to IkappaB-kinase and SAPK), able to bind the regulatory sub-unit NEMO/IKKgamma and to activate NF-kappaB. Here, we demonstrate that CIKS forms homo-oligomers, interacts with NEMO/IKKgamma, and is recruited to the IKK-complex upon cell stimulation. In addition, we identified the regions of CIKS responsible for these functions. We found that the ability of CIKS to oligomerize, and to be recruited to the IKK-complex is not sufficient to activate the NF-kappaB. In fact, a deletion mutant of CIKS able to oligomerize, to interact with NEMO/IKKgamma, and to be recruited to the IKK-complex does not activate NF-kappaB, suggesting that CIKS needs a second level of regulation to efficiently activate NF-kappaB.  相似文献   

5.
Trifluoperazine inhibits the activation of phosphodiesterase by binding to the calcium-dependent activator. To determine further the specificity by which trifluoperazine binds to activator, we compared the binding of trifluoperazine to activator prepared from several species and tissues and to a number of other calcium-binding proteins devoid of activator activity. Trifluoperazine binds to activator prepared from human, bovine, rat and rabbit brain and from chick embryo fibroblasts. In each case, the binding of trifluoperazine to activator was qualitatively similar and related quantitatively to the ability of the preparation to activate phosphodiesterase. Of the other calcium-binding proteins examined, namely, troponin-C, S-100 protein, phospholipase A, phospholipase B and myosin light chain, only troponin-C displayed any significant calcium-specific binding of trifluoperazine. The binding to troponin-C, however, appeared to be different from the binding to activator; whereas the binding of trifluoperazine to actovator showed no cooperativity, the binding to troponin-C showed positive cooperatively. These results and earlier data showing that trifluoperazine fails to bind to a variety of other proteins, indicate that the binding of trifluoperazine to the calcium-dependent activator of phosphodiesterase is selective and suggest that this binding may explain some of the biochemical and pharmacological actions of this antipsychotic agent.  相似文献   

6.
Monoclonal antibodies (MAb) were raised to the Escherichia coli K-12 ferric enterobactin receptor, FepA, and used to identify regions of the polypeptide that are involved in interaction with its ligands ferric enterobactin and colicins B and D. A total of 11 distinct FepA epitopes were identified. The locations of these epitopes within the primary sequence of FepA were mapped by screening MAb against a library of FepA::PhoA fusion proteins, a FepA deletion mutant, and proteolytically modified FepA. These experiments localized the 11 epitopes to seven different regions within the FepA polypeptide, including residues 2 to 24, 27 to 37, 100 to 178, 204 to 227, 258 to 290, 290 to 339, and 382 to 400 of the mature protein. Cell surface-exposed epitopes of FepA were identified and discriminated by cytofluorimetry and by the ability of MAb that recognize them to block the interaction of FepA with its ligands. Seven surface epitopes were defined, including one each in regions 27 to 37, 204 to 227, and 258 to 290 and two each in regions 290 to 339 and 382 to 400. One of these, within region 290 to 339, was recognized by MAb in bacteria containing intact (rfa+) lipopolysaccharide (LPS); all other surface epitopes were susceptible to MAb binding only in a strain containing a truncated (rfaD) LPS core, suggesting that they are physically shielded by E. coli K-12 LPS core sugars. Antibody binding to FepA surface epitopes within region 290 to 339 or 382 to 400 inhibited killing by colicin B or D and the uptake of ferric enterobactin. In addition to the FepA-specific MAb, antibodies that recognized other outer membrane components, including Cir, OmpA, TonA, and LPS, were identified. Immunochemical and biochemical characterization of the surface structures of FepA and analysis of its hydrophobicity and amphilicity were used to generate a model of the ferric enterobactin receptor's transmembrane strands, surface peptides, and ligand-binding domains.  相似文献   

7.
Evidence is presented that suggests that PHA-L4 may exert the therapeutic effects of a theoretical ideal biological response modifier through its ability to do the following: to assist remission induction in certain malignancies, to exhibit direct antitumor cytotoxic effects, to enhance antineoplastic effect of radiation and chemotherapy, to decrease the liability to malignant transformation, to promote differentiation and restore normal growth responses in neoplastic cells, to manifest minimal liability to suppressor activity that would inhibit tumor rejection or antitumor cytotoxicity, to repress graft rejection and graft-versus-host responses and amplify the immunosuppressive effects of other agents in allograft transplantations, to display a direct protective effect against damage from radiation and chemotherapy, to stimulate normal myelopoiesis, to reinforce responses against various infections, to amplify tumor immunogenicity, and to attract mononuclear cells to sites of injection or local application.  相似文献   

8.
刘文萍 《四川动物》2005,24(4):529-531
横断山区的蝶类561种,隶属于12科,208属.在12科中,种类最多的是蛱蝶科148种,其次是眼蝶科117种,灰蝶科65种,凤蝶科63种,粉蝶科60种,弄蝶科60种,蚬蝶科18种,绢蝶科12种,斑蝶科9种,环蝶科6种,喙蝶科2种,珍蝶科1种.分布于横断山区的珍稀蝴蝶有44种,其中国家Ⅰ级保护的1种,Ⅱ级保护的3种.  相似文献   

9.
宁波沿海平原第四纪沉积物属于海陆交互沉积,记录了良好的古气候变化信息,是研究古气候冷暖变化、沉积物沉积特征的良好载体.对位于宁波沿海平原东南部的Z02孔进行14C和古地磁测年,根据钻孔岩性、孢粉组合、有孔类和介形类组合、粒度等环境替代指标特征,确定了 Z02孔第四纪地层划分,揭示了研究区第四纪以来的古环境演变信息.结果...  相似文献   

10.
Kainic acid (4.7 mM) applied to the rostral ventrolateral medulla (RVLM) surface decreases phrenic output, CO2 sensitivity, and blood pressure in chloralose-urethan-anesthetized, vagotomized, paralyzed, glomectomized, servoventilated cats. In this study using the same preparation, bilateral 50- to 100-nl kainate injections just below the RVLM surface better localized these responses topographically. The physiological responses to unilateral 10-nl kainate injections were then correlated with anatomic location determined by fluorescent microbeads (0.5 micron diam). Many sites were associated with no effect, a few rostral and caudal sites with increased phrenic activity, and cluster of sites with decreased phrenic activity often to apnea, decreased CO2 sensitivity, and decreased responses to carotid sinus nerve stimulation. Blood pressure was unaffected. These sites, within 400 microns of the surface, were ventral to the facial nucleus, ventrolateral to the nucleus paragigantocellularis lateralis, caudal to the superior olive, and rostral to the retrofacial nucleus. They appeared to be within the recently described retrotrapezoid nucleus, which contains cells with respiratory-related activity and projections to the dorsal and ventral respiratory groups. Cells within this site appear able to provide tonic input to respiration and to affect peripheral and central chemoreception.  相似文献   

11.
This study assessed the effectiveness of operant conditioning in training three species of captive callitrichid primates (Leontopithecus rosalia, Callithrix geoffroyi, and Saguinus imperator) to urinate on demand. There were three goals to the study: 1) to develop a system for quantitatively assessing positive reinforcement training; 2) to ascertain whether or not positive reinforcement techniques can be used to train callitrichid monkeys to urinate on demand, and if so, how many training sessions are required; and 3) to determine the effect on urination behavior of the trainer entering the cage to collect a urine sample. Positive reinforcement with a continuous reinforcement schedule was used to capture a natural behavior: urination. Training sessions (30 min each) were conducted at dawn thrice weekly during five consecutive phases: habituation, control, training (animals were rewarded for urinating), maintenance (animals had reached a defined training criteria and continued to be rewarded for urinating), and collection (animals were rewarded for urinating, and the trainer entered the cage to collect the sample). The numbers of 30-min training sessions required to train the three monkey species (L. rosalia, C. geoffroyi, and S. imperator) were five, six, and eight, respectively. For the three species, the mean number of urinations per animal was significantly greater during the training, maintenance, and collection phases compared to the control phase. However, the three species differed significantly in the manner in which the rates of urination changed across the five phases. A higher proportion of subjects urinated during the training, maintenance, and collection phases compared to the control phase. Latency to first urination varied significantly across the five phases, with significantly reduced latencies to urinate during the training, maintenance, and collection phases compared to the control phase. The entry of the trainer into the cage to collect the urine sample did not appear to alter urination behavior. We demonstrate that operant conditioning techniques, which typically incur minimal cost, time investment, and disturbance, can be used to increase the quantity of urine samples collected for physiological analysis, the proportion of animals that urinate, and the speed of sample collection.  相似文献   

12.
湖北省褐飞虱对吡虫啉、噻嗪酮及氟虫腈的抗药性监测   总被引:2,自引:0,他引:2  
采用稻茎浸渍法监测湖北省武穴、天门、监利、通城、孝感、公安及枣阳七地褐飞虱Nilaparvata lugens(Sta1)田间种群对吡虫啉、噻嗪酮、氟虫腈的抗药性。结果表明:2006、2007和2008年3年7地褐飞虱种群对吡虫啉的抗性分别为98.89~389.19倍、69.00~153.33倍和56.32~116.89倍,达高水平至极高水平抗性,但3年期间总体抗性水平呈现一定程度的下降趋势;2007和2008年2年7地褐飞虱对噻嗪酮的抗性分别为13.39~41.06倍和6.94~20.44倍,达低水平至高水平抗性;2007和2008年2年7地褐飞虱对氟虫腈抗性分别为0.97~2.64倍和0.63~1.42倍,为敏感阶段。此外,还对褐飞虱的治理进行讨论。  相似文献   

13.
14.
消毒剂是一种可杀灭物体表面、器材设备、皮肤、空气和水源等传播媒介上携带的病原微生物的有机分子。它在体外能杀灭病原微生物,切断其传播途径,进而达到控制污染的目的,在生命安全防控中起着重要的作用。但是不合理地使用消毒剂导致细菌对消毒剂产生耐药。消毒剂耐药基因在不同种属间的水平转移加剧其传播风险,使消毒剂耐药情况进一步恶化。更令人担忧的是,细菌对消毒剂的耐药可能会导致对抗生素产生共耐药,给公共安全带来巨大的威胁。但目前为止,对消毒剂耐药以及共耐药的认识还不够全面。本文总结了关于细菌对消毒剂耐药的研究报道,对消毒剂的作用机制、细菌对消毒剂的耐药机制进行了论述,另外针对消毒剂耐药基因的传播以及细菌对消毒剂和抗生素的共耐药进行了综述,为减少消毒剂耐药性的产生和制定合理的消毒剂使用规范奠定基础。  相似文献   

15.
Describing resources and their relationships with organisms seems to be a useful approach to a ‘unified ecology’, contributing to fill the gap between natural and human oriented processes, and opening new perspectives in dealing with biological complexity. This Resource Criterion defines the main properties of resources, describes the mechanisms that link them to individual species, and gives a particular emphasis to the biosemiotic approach that allows resources to be identified inside a heterogeneous ecological medium adopting the eco-field model. In particular, this Criterion allows to couple matter, structured energy and information composing the ecological systems to the biosemiotic and cognitive mechanisms adopted by individual species to track resources, transforming neutral surroundings into meaningful species-specific Umwelten. The expansion of the human semiotic niche that is a relevant evolutionary process of the present time, assigns the role of powerful and efficient agency to the Resources Criterion to evaluate the effect of human intrusion into the natural systems with habits of key stone species, under the challenge of a growing use of alloctonous, immaterial and symbolic resources of the actual globalized societal models. The Resource Criterion interprets the ecological dynamics contributing to complete the epistemology of the ecology, to open a bridge toward economy and other societal sciences, and to contribute to formulate a General Theory of Resources.  相似文献   

16.
It behooves physicians to be aware that adolescents are different people, that they have a vast capacity for change, that they often exhibit the sickest kind of behavior, which may be very frightening to us and to them.Physicians have to be able to wait and not become panicked by the turbulences, confusions, and contradictions that mark the adolescent''s behavior; to keep in mind at all times that much of what is going on is relatively normal behavior in the drive toward maturation and adulthood; that the adolescent has to cope with his sexual drive which is continually frustrated, that he has to cope with the problems of emancipation from parental authority, that he has to cope with an aggressive drive to achieve and to dominate.Parents, too, have to be understanding and ready to render unselfish support, for they continue to be the source of strength and security, and even the source of healthy restrictions. Adults must be aware that the adolescent struggles with his conscience and its dictates, and we should look upon cliques, groups and clubs as a healthy assistance in the preservation of standards, ethics, and mores.  相似文献   

17.
The phenomenon of transference to a medical center is similar to the transference given to an individual physician, the feelings being invested in The Center rather than in a person. The reputation and the image of The Center can give therapeutic sustenance.There are common features to each healing organization from primitive times to the journeys to the Oracles at the shrine of Zeus at Dodona and Apollo at Delphi, to Mecca and St. Bartholomew''s Hospital, to Lourdes and Gheel, and to the present-day medical center. A phenomenon which we have identified as Transference to a Center has previously been known to physicians, theologians, historians, sociologists and anthropologists, by different names. In a social sense, transference to a medical center is akin to an Edifice complex.  相似文献   

18.
E Single  J Rehm  L Robson  M V Truong 《CMAJ》2000,162(12):1669-1675
BACKGROUND: In 1996 the number of deaths and admissions to hospital in Canada that could be attributed to the use of alcohol, tobacco and illicit drugs were estimated from 1992 data. In this paper we update these estimates to the year 1995. METHODS: On the basis of pooled estimates of relative risk, etiologic fractions were calculated by age, sex and province for 90 causes of disease or death attributable to alcohol, tobacco or illicit drugs; the etiologic fractions were then applied to national mortality and morbidity data for 1995 to estimate the number of deaths and admissions to hospital attributable to substance abuse. RESULTS: In 1995, 6507 deaths and 82,014 admissions to hospital were attributed to alcohol, 34,728 deaths and 194,072 admissions to hospital were attributed to tobacco, and 805 deaths and 6940 admissions to hospital were due to illicit drugs. INTERPRETATION: The use and misuse of alcohol, tobacco and illicit drugs accounted for 20.0% of deaths, 22.2% of years of potential life lost and 9.4% of admissions to hospital in Canada in 1995.  相似文献   

19.
殷文  柴强  樊志龙  胡发龙  赵财  于爱忠 《生态学杂志》2018,29(11):3658-3668
合理的种植模式可以提高资源利用效率,降低农业生产的生态环境风险,实现资源节约和增产增效的目的.本文运用能值分析的理论和方法,从资源利用、碳排放、经济效益、能值自给率和净能值产出率等方面对干旱灌区典型种植模式的生产效应进行综合分析与评价,以期为建立减投、减排、高产高效、可持续农田高效生产模式提供理论与实践依据.结果表明:集成免耕秸秆覆盖还田及地膜再利用的高效间作生产模式(NTSI)具有明显的增产效应,与地方传统间作(CTI)和单作玉米(CTM)相比,分别增产13.5%~16.9%和13.8%~17.1%.NTSI较CTI模式水分利用效率和光能利用率分别提高12.4%~17.2%和6.1%~8.1%.高效NTSI模式可降低系统碳排放、提高碳排放效率,与CTI和CTM相比,碳排放总量分别降低618~895和1804~2002 kg·hm-2,降低幅度分别为12.1%~16.4%和28.6%~31.0%;相反,碳排放效率分别提高29.3%~40.1%和58.9%~71.4%.高效NTSI模式具有明显的资源减投潜力,与CTI和CTM相比,总投入分别降低1424~1431和501~1547 元·hm-2,减投比例分别为12.6%~13.6%和4.9%~14.6%;总产值分别提高11.2%~11.8%和24.4%~36.3%(增加4309~4603和8439~11057元·hm-2);纯收益分别增加19.6%~22.4%和40.1%~57.7%(增多5740~6027和9544~11558元·hm-2).因而,NTSI模式具有较高的产投比和单方水效益,与CTI和CTM相比,产投比分别提高27.9%~29.0%和40.5%~45.6%;单方水效益提高幅度分别达到19.9%~23.2%和27.7%~39.3%.高效NTSI模式能值自给率达到57.2%,较CTI和CTM生产模式分别提高4.0%和12.2%,NTSI模式净能值产出率达到0.173,较CTI高10.0%,但比CTM低11.7%.从资源利用、碳减排、经济效益、可持续发展角度综合考虑,集成免耕秸秆覆盖还田及地膜两年利用的高效小麦间作玉米模式具有较高的经济活力,农业系统整体功能较好,运转效率较高,能值回报率较高,是适用于干旱绿洲灌区的资源减投、减排、高产高效的种植模式.  相似文献   

20.
Cognitive mechanisms are an important part of the organization of the behavior systems of animals. In the wild, animals regularly face problems that they must overcome in order to survive and thrive. Solving such problems often requires animals to process, store, retrieve, and act upon information from the environment—in other words, to use their cognitive skills. For example, animals may have to use navigational, tool-making or cooperative social skills in order to procure their food. However, many enrichment programs for captive animals do not include the integration of these types of cognitive challenges. Thus, foraging enrichments typically are designed to facilitate the physical expression of feeding behaviors such as food-searching and food consumption, but not to facilitate complex problem solving behaviors related to food acquisition. Challenging animals by presenting them with problems is almost certainly a source of frustration and stress. However, we suggest here that this is an important, and even necessary, feature of an enrichment program, as long as animals also possess the skills and resources to effectively solve the problems with which they are presented. We discuss this with reference to theories about the emotional consequences of coping with challenge, the association between lack of challenge and the development of abnormal behavior, and the benefits of stress (arousal) in facilitating learning and memory of relevant skills. Much remains to be done to provide empirical support for these theories. However, they do point the way to a practical approach to improving animal welfare—to design enrichments to facilitate the cognitive mechanisms which underlie the performance of complex behaviors that cannot be performed due to the restrictions inherent to the captive environment.  相似文献   

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