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1.
Animal tissue extracts show a derivative (alternating-current) polarographic waves at ?1.7 V (B-wave) and frequently a second wave at ?1.4 V (A-wave) against S.C.E.A third wave around ?1.9 V (C-wave) vs S.C.E. was found in the extracts of malignant mammalian tumors and in noncancerous tissues of tumor bearing animals. The ?1.9 V wave was also frequently present in normal (noncancerous)-human urine. The same signal was always missing from the tissue extracts of animals without cancer and urine of human cancer patients.The formation of C-wave is dependent upon the simultaneous presence of three factors: the C-substances, which seems to be nitrogen containing carbohydrate, halogen ions and certain hydrogen ion concentration. A possible relation between the C-wave producing compounds and the immunological specificity of the cell surface is discussed.  相似文献   

2.
Summary

The phenomenon of “flagellate spermatogenesis” typically known among marine invertebrates with “primitive” sperm and external or external-internal fertilization is discussed. It is suggested that “flagella bearing” in early germinative cells might be explained by plesiomorphic similarity between these cells and flagellate somatic epithelial cells. The early germ cells of more apomorphic multicellular animals using internal fertilization with “modified” and “aberrant” sperm typically have no flagella and this organelle, as the sperm tail, first appears in spermatids. It is speculated that the “flagellate” pattern typifies the basal level and that the transition between “flagellate” and “specialized” spermatogenesis constitutes a significant step in evolution.  相似文献   

3.
A “crude plastid” preparation from young pea leaves converts linoleate [1-14C] or [U-14C] (ammonium salt or free acid) into a C12 dibasic acid with a double bond at Δ9.  相似文献   

4.
An important role in cell metabolism is played by transport of C4-dicarboxylates (C4-DCB). Specifically, they are intermediates of the citrate cycle. Transport of succinate across the mitochondrial membrane provides correlation between metabolism in peroxysomes and in mitochondria. There is known transport of C4-DCB across all kinds of energy-transforming membranes of the animal, plant, fungal, and bacterial cells. This review summarizes molecular characteristics of the C4-DCB transporters. Of particular interest are primary structures for the transporters with the known kinetic mechanism and kinetic transport parameters. For each studied group of organisms, the number of transmembrane segments in the carried molecule or the character of specificity does not correlate with the certain transport mechanism—antiport, symport with proton or symport with cation. The review describes perspective methodical approaches allowing association of peculiarities of structure with transport mechanism for individual transporters, preparation of functional hybrid transporters—“protein chimeras,” scanning of transporter transmembrane segments with aid of essential acids, probing of the transporter active center with aid of alkyl and acyl substrate derivatives used to obtain the “lipophilic profile” of the channel of the C4-DCB transporter. It is recommended to use these approaches to one transporter that has small sizes and large substrate specificity.  相似文献   

5.
Based on an analysis of L.S. Vygotsky's concepts of “units” and “elements” of psychological systems, this article highlights five of their attributes. It shows that these attributes are logically symmetrical, since in their wording they can be converted into one another by negation or by replacing some words with their opposites. This suggests that the concepts of the “unit” and “element” of a system are different poles of one theoretical construct of the activity of human psychology. Thus methods for the study of psychological systems by breaking them down into elements or by separating them into units can be seen as complementary. The article describes differences among the concepts of “unit,” “minimal unit,” and “cell” of a psychological system. It reviews several problems that are solvable using the “method of units,” as well as some concepts of the theory of psychological systems that are understood as holistic, conceptual, and active processes and/or results of human interaction with the world. Among the examples of such systems are “systems of psychological functions” (according to Vygotsky), as well as separate activities (according to A.N. Leontiev), human actions and operations (interactions with the world on the level of objects and mental or physical means). The “component” of a psychological system is defined as any “something” that in some sense belongs to or is included in human interaction with the world. A component that belongs to the system is called an “element” of it, but a component that is included in the functioning and development of the system is called a “part” of it. The article presents the mathematical and psychological foundation of these definitions. It identifies and discusses the substantial (independently existing) components of psychological systems and their attributes (properties and conditions). It describes the relationships between them using the bipolar theoretical constructs “part-element” and “substantial-attributive” component of a system.  相似文献   

6.
We studied the effect of genetic transformation on biologically active compound (artemisinin and its co-products (ART) as well as sugars) accumulation in Artemisia vulgaris and Artemisia dracunculus “hairy” root cultures. Glucose, fructose, sucrose, and mannitol were accumulated in A. vulgaris and A. dracunculus “hairy” root lines. Genetic transformation has led in some cases to the sugar content increasing or appearing of nonrelevant for the control plant carbohydrates. Sucrose content was 1.6 times higher in A. vulgaris “hairy” root lines. Fructose content was found to be 3.4 times higher in A. dracunculus “hairy” root cultures than in the control roots. The accumulation of mannitol was a special feature of the leaves of A. vulgaris and A. dracunculus control roots. A. vulgaris “hairy” root lines differed also in ART accumulation level. The increase of ART content up to 1.02?mg/g DW in comparison with the nontransformed roots (up to 0.687?mg/g DW) was observed. Thus, Agrobacterium rhizogenes-mediated genetic transformation can be used for obtaining of A. vulgaris and A. dracunculus “hairy” root culture produced ART and sugars in a higher amount than mother plants.  相似文献   

7.
Within four hours of adding fibroblast growth factor, epidermal growth factor, prostaglandin F, or serum to quiescent Balbc 3T3 cells we observe selective increases in the incorporation of [35S]methionine into six proteins; “major excreted protein” (MEP) and five “superinducible proteins” (SIPs). The mechanisms regulating the extracellular expression of MEP and the SIPs differ. 1) The levels of MEP but not SIPs are increased by NH4Cl; and 2) Cycloheximide increase SIP and decreases MEP production. These results suggest that production of MEP and the SIPs are controlled by other proteins; MEP by a positive, and the SIPs by a negative effector.  相似文献   

8.
The water extract of soybean seeds (Glycine max (L.) Merr.) is nearly tasteless, but “kokumi” taste sensation was confirmed upon addition of a basic umami solution containing glutamic acid, inosine monophosphate, and sodium chloride. To identify the key contributors to the “kokumi” taste sensation in soybean seeds, sensory-guided fractionation, taste sensory analyses, and LC–MS/MS analyses were utilized. γ-glutamyl-tyrosine and γ-glutamyl-phenylalanine were identified as contributors to “kokumi taste”; specifically, these γ-glutamyl peptides imparted the “kokumi” taste sensation at a low taste threshold in a basic umami solution. Raffinose and stachyose, which are sufficiently present in soybean seeds, exhibited a synergistic effect in regard to the enhanced “kokumi” taste sensation of γ-glutamyl peptides. This is the first report that the combined use of γ-glutamyl peptides and oligosaccharides can increase the “kokumi” intensity, which suggests that soybean extracts or soymilk can be used to enhance the “kokumi” taste sensation in food products.  相似文献   

9.
A mixture of C28 and C29 sterols have been isolated from Leptosphaeria typhae grown in vitro on “oat water” and characterized by GLC and MS. Mono-, di- and tri-unsaturated sterols are present in the extracts of fungi cultivated both in the dark and in the light but the sterol composition is different. The influence of “oat water” on sterol structure has been determined by comparison with the sterols of the same fungus grown on synthetic medium in the dark.  相似文献   

10.
This article presents detailed comments on L.S. Vygotsky's review of the famous Russian ballerina E.V. Gel'tser's performance during her Gomel tour in the autumn of 1922. We present a reconstruction of the cultural context, which is quite essential for understanding multiple aspects of the content of Vygotsky's review. We stress the importance of the distinction between artificial and natural movements introduced by Vygotsky's when considering the uniqueness of expressive movement in choreography.

The uniqueness of cathartic experience, which became a central theme in Vygotsky's research monograph The Psychology of Art (1925), is examined in this review using the analysis of classical dance perception. We establish the methodological importance of Vygotsky's account of the opposition between classical and so-called untaught, natural dance (I. Duncan and M. Fokine), which in turn makes it possible to designate the fundamental difference between “spiritual” [dukhovnyi] and “mental/emotional” [dushevnyi] experience.  相似文献   

11.
Physico-chemical properties of erythrocyte glucose-6-phosphate dehydrogenase including erythrocyte G6PD activity, Michaelis constants, KmG6P and NADP, pH optimum, thermostability and molecular weight were investigated in “brown-howler” monkeys and then compared with the values of human G6PD B(+). The values of Michaelis constants (KmG6P and NADP) pH optimum were the same as the values of human G6PD B(+). The human G6PD has a dimeric form in the assay conditions employed in the present study, monkey enzyme showing great similariy with human one. Otherwise, the thermostability differed from the human G6PD. The simian enzymatic activity was about four times higher than the human G6PD. A comparison of physico-chemical properties of glucose-6-phosphate dehydrogenase among primates is also presented.  相似文献   

12.
The freshwater secondarily aquatic plants, most of which are higher plants, are those returned to the water environment after spending a period of time living on land. The readaptation to living underwater has made it necessary for these plants to put in place morphological and functional strategies to cope with some major problems due to features of the aquatic environment, but also deriving from the specialized organization of their “terrestrial” bodies. The poor O2 availability underwater accounted for the evolution of wide aerenchyma tissues throughout the plant organs to improve the photosynthetic O2 flux from the shoot to the roots buried in anoxic sediments and to the neighboring rhizosphere. This favors sediment oxygenation, sustains the aerobic metabolism of roots, and improves the availability and uptake of mineral nutrients, whose delivery to the entire plants, without a transpirational flux, is ensured by an acropetal mass transport depending on root pressure, guttation from hydathodes and channeling by apoplast closure around the vascular tissues. A great expansion of leaf surfaces and an enhanced surface:volume ratio of chloroplast-rich photosynthetic cells help to contact the water medium and to increase the cell/environment exchanges to gain inorganic carbon. Furthermore, different physiological mechanisms operate to cope with the scarce availability of CO2 and the prevalence of HCO3 ? as inorganic carbon form in water. Some of them, like cell wall acidification through H+ extrusion by a light-dependent APTase or activation of an apoplastic carbonic anhydrase, operate outside the cells, leading to a conversion of HCO3 ? to CO2, which then diffuses into the cells. Others, on the contrary, act inside the cells to load the active site of Rubisco with CO2, thus favoring photosynthesis and lowering photorespiration. Aquatic macrophytes with isoetid life form, moreover, can obtain most ot the fixed CO2 from sediments. In submerged species, in additin to the C3 cycle, the C4 and CAM-like photosynthetic metabolisms can also operate, and are modulated by the environmental inorganic carbon availability and the plant photosynthetic demand. Interestingly, in the aquatic plants the C4 pathway, which can be concomitant with the C3 one, does not depend on the Kranz anatomy of leaves, but relies on the intracellular compartmentation of carboxylative and decarboxylative enzymes. The CAM-like pathway, defined AAM, which also coexists with the C3, allows the submerged plants to fix CO2 in the dark, thus exploiting the higher CO2 availability in the water medium during the night, and extending to 24?h the period of inorganic carbon assimilation. In almost all the aquatic macrophytes the AAM is only expressed in the submersion state, whereas it is quickly inactivated in emerging leaves in a cell by cell way.  相似文献   

13.
前列腺Ⅰ号抗炎镇痛作用以及抗前列腺炎的实验研究   总被引:2,自引:0,他引:2  
采用热板法和扭体法观察前列腺Ⅰ号抗炎、镇痛以及抗大鼠实验性前列腺炎的作用。采用小鼠耳廓二甲苯制炎法观察抗炎作用,前列腺炎模型采用向大鼠前列腺组织内注入角叉菜胶的方法。结果显示前列腺Ⅰ号能减少小鼠扭体反应数,延长小鼠热板法引起的痛反应潜伏期,对小鼠耳廓肿胀有明显的抑制作用,前列腺炎模型试验中,前列腺液检查卵磷脂小体明显增加,白细胞数降低。因此前列腺Ⅰ号具有明显的抗炎、镇痛以及抗前列腺炎的作用。  相似文献   

14.
The use of a single, commercially available column packing, TabsorbR, is described for the g. l. c. separation of a large number of different compounds. The resolution of the homologous members of the following series of compounds was achieved: (1) saturated fatty acids (C1-C18), (2) normal aliphatic saturated dlcarboxylic acids (C2-C14), (3) normal aliphatic saturated alcohols (C1-C24), (4) normal aliphatic saturated amines (C1C12), (5) the common amino acids except arginlne, histidlne and cysteine, (6) aliphatic hydrocarbons (C10-C20) and (7) monosaccharides. It should be noted that twenty-two monosaccharides including three hexosamines and two anhydrohexoses, could be resolved as aldltol acetates In a single run. In addition, galacturonic, glucuronic and lduronlc acids could be separated from one another as their 1, 4-lactones. The resolution achieved in these series of compounds was found to be consistent and highly reproducible. It is of further interest that certain Isomers of the higher fatty acids and hydrocarbons with one double bond could also be separated from the normal and saturated compounds, respectively. The applicability of “Tabsorb” for the g. l. c. separation, although noted above to be considerably broad, is by far not yet exhausted. These procedures which form the basis for the quantitative determinations of the various compounds studied as demonstrated by analysis of glycopeptldes for neutral hexoses and proteins for the amino acids, can readily be adapted to preparative methods. From the biochemical point of view “Tab-sorb” is an extremely versatile column packing in that it can be used for the identification of many of the common building blocks of natural products.  相似文献   

15.
Scorpions are one of the most important taxa for ecological, conservation, and biogeographic studies. Biodiversity in the pampean grassland hilly environment is relevant because of the high number of native plant and animal taxa. We studied the diversity, abundance and phenology of a scorpion community in a natural reserve from central Argentina. Samples were taken monthly using 10 pitfall traps. Five species of scorpions (269 individuals) were observed in the study site (Bothriuridae). Bothriurus prospicuus was the most abundant species with 40.15% of the total individuals captured. The Shannon index was H´ = 0.69 and the evenness index was 0.83. Scorpion abundance was significantly different between months and was significantly correlated with monthly mean temperature. The knowledge on the scorpion fauna in “Ernesto Tornquist” Provincial Park could help in the preservation of natural grassland habitats.  相似文献   

16.
During the summer of 1980, numerous exposed native littleneck clams (Protothaca staminea) were observed in Sequim Bay, Washington. The kidneys of these clams were found to be parasitized by a coccidian. Heavily parasitized kidney was characterized by massive epithelial destruction and an intense inflammatory response. In addition, large numbers of “brown cells” were present throughout the tissues of infected clams.Infected kidneys harbored several stages of the life history of the parasite. The present coccidian differs markedly in several respects from other coccidians in bivalves. First, the entire life history apparently occurs in the kidney of the clam, in contrast to the presumed involvement of an alternative host in other known coccidian parasites of bivalves. Second, a thick-walled spore is produced in addition to a thin-walled oocyst. The apparent presence of two types of dissemination stages is unknown in the Coccidia. Finally, the sporocysts are tetrazoic as opposed to dizoic or multiple sporocysts in previously described species. This parasite, therefore, appears to represent an undescribed genus and species of Coccidia.  相似文献   

17.
The switch from HbA (α2β2A) to HbC (α2β2C) synthesis was induced by injection of erythropoietin into a lamb homozygous for HbA. Serial samples of bone marrow were analyzed to detect the initial commitment of erythroid stem cells (CFU-E) to form colonies which made HbC in vitro, and to detect the initial accumulation of βC-globin mRNA and the onset of HbC synthesis in erythroblasts in vivo. CFU-E-derived erythroid colonies were formed in plasma clot culture at a low erythropoietin concentration, and the relative amounts of βA- and βC-globin synthesized were determined after a 24 hr pulse of 3H-leucine, added after 84 hr in culture. RNA was extracted from nuclei and cytoplasm of “early” and “late” populations of bone marrow erythroblasts which had been fractionated by Ficoll-Hypaque density centrifugation. The concentration of βA- and βC-globin mRNA was determined by annealing to purified synthetic DNAs (cDNAs) complementary to βA and βC mRNA. No βC-globin was synthesized in erythroblasts or in CFU-E-derived erythroid colonies prior to the injection of erythropoietin. An increase in the concentration of CFU-E in the bone marrow and the appearance of βC-globin synthesis in CFU-E-derived colonies were detected 12 hr after the erythropoietin injection. In contrast, βC mRNA was not detected in either “early” or “late” erythroid cells until 36 hr later. The first measurable βC-globin mRNA was accompanied by the appearance of βC-globin synthesis in bone marrow erythroblasts. Our results suggest that the accumulation of βC-globin mRNA is a relatively late event following induction of HbA to HbC switching by erythropoietin. The expansion of the compartment of erythroid stem cells and the commitment of CFU-E to βC-globin synthesis appear to precede the detectable accumulation of βC mRNA by 24–36 hr.  相似文献   

18.
The grass Trisetum flavescens causes severe calcification of soft tissues upon ingestion by various species, which has been ascribed by others to a 1,25(OH)2 vitamin D3-like activity.By a special purification procedure involving high pressure liquid chromatography and continuous biological testing the active principle was purified. By means of GCMS it was identified as cholecalciferol, being present in a concentration of about 0.1 ppm in the lyophylized plant dry matter. 1,25(OH)2 vitamin D3 or other metabolites of vitamin D3 were not present. Since such low concentrations could hardly explain the calcinosis observed, a more active “bound form” of vitamin D3 may be present in Trisetum flavescens.  相似文献   

19.
Circulating schistosome antigens (CSA) and circulating immune complexes (CIC) were investigated during the course of Schistosoma mansoni infection in mice. The radioimmunoprecipitation-polyethylene glycol (PEG) assay (RIPEGA) with [125I]anti-S. mansoni antibodies or [125I] anti-antigen “4” antibodies detected, respectively, total CSA and antigen “4” in serum and in 3% polyethylene glycol-precipitated CIC from infected mice. Complement fixation test and [125I] C1q-binding test revealed, respectively, an anticomplementary activity and the presence of C1q-binding CIC. All these substances appeared in infected mice at approximately the same period, i.e., between the 40th- and the 55th- day postinfection. No correlation was observed between the detection of anticomplementary active substances and C1q-binding CIC. In contrast, a close relationship was noticed between CSA and complement-activating material during the course of the infection. This suggests that substances with anticomplementary activity in serum from infected mice could be one or various CSA. A close correlation was also observed between C1q-binding CIC and free or “complexed” antigen “4.” This observation supports well the possibility that antigen “4” is one of the major complexed circulating antigen present in schistosomiasis. The immunoglobulins G1, G2a, M, and A were also characterized in 3% PEG-precipitated CIC from infected mice during the period in which we detected C1q-binding CIC. The roles played by specific S. mansoni CIC in either schistosomal nephropathy or protective mechanisms to a challenge infection in mice are discussed.  相似文献   

20.
海洋生态环境健康已成为制约海洋经济发展的关键因素,科学评估近岸海洋生态环境整体的健康状况对持续利用海洋资源环境十分紧要。本研究基于新构建的以海洋生态系统自身状态为内核、以人类社会经济学指标为外核的“双核”评价框架和2008—2016年的调查资料,对烟台近岸海洋环境健康状况进行综合评估。结果表明: 烟台近岸海域的内核评级以“优”、“良”为主,总体上沉积物质量最好,水体环境质量稍差,而生物群落则是决定最终评级的核心因素;外核评价方面,以海洋产业产值和海洋保护区面积计算的外核得分为0.98。烟台近海最终的“双核”评价结果为“优/良+0.98”,这表明烟台近岸海域在保持高开发利用程度的情况下,目前海域生态环境健康状况仍然良好,但部分区域已经开始恶化,需在发展海洋产业的同时予以密切关注。“双核”框架的评价结果可为海洋资源开发和环境保护的管理决策提供指导,对实现海洋资源环境的可持续利用具有重要意义。  相似文献   

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