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51.
Changes in macromolecule syntheses, especially RNA synthesis, and the energy providing system were investigated in seeds ofAgrostemma githago aged for different periods. In embryos of aged seeds all macromolecule syntheses start later and reach a lower level than young ones. It was found that the synthesis of rRNA in embryos of aged seeds is reduced whereas the synthesis of poly (A+) RNA in relation to the total RNA synthesis is highly increased as well as the amount of this RNA species with long poly (A) chains. The results are discussed in connection with the decreased protein synthesis and the reduced ATP content and ATP formation ability in embryos during the long time storage of seeds.  相似文献   
52.
This paper is a study of the parasitic fungi of Manisa. 32 species of parasitic fungi have been discovered of which 2 species are new for the Turkish parasitic fungal flora. Also, new hosts for 13 of these species are reported in Turkey for the first time.  相似文献   
53.
Aggregation of rat hepatocytes was effectively inhibited by monovalent antibodies (Fab fragments) directed against hepatocyte plasma membranes, but monovalent antibodies against some distinct, known hepatocyte surface antigens had no effect. Surface antigens, which neutralized the Fab inhibiting effect on cell aggregation, could be solubilized from plasma membranes by limited proteolytic digestion. Thus, hepatocyte intercellular adhesion seems to involve specific cell surface components, which may be proteins or protein derivatives.  相似文献   
54.
In this study, the simultaneously recorded and selectively averaged evoked potentials in some of the structures of the auditory pathway (acoustical cortex, medial geniculate nucleus, inferior colliculus), in the reticular formation and the hippocampus of the awake cat as well as the simultaneous amplitude frequency characteristics of these structures are given. The power spectral density functions computed from the simultaneously recorded spontaneous activity of these structures are also presented. Using these results, the following analyses are accomplished: (1) determination of the dynamics of potentials simultaneously obtained from various brain structures, in order to evaluate the common features of their system characteristics; (2) determination of the relationship (or interactions) between rhythmic activity and evoked potentials of the brain, and (3) elaboration of a working hypothesis for the dynamics of potentials of the brain. Some suggestions and comments are also made for investigators working toward theories or dynamic models of signal transmission in the brain.  相似文献   
55.
The taxonomy and morphology of Aktedrilus Knöllner, 1935 and Bacescuella Hrabe' 1973 (subfamily Phallodrilinae), both common genera of the marine, littoral meiofauna, were studied on the basis of material from various geographical areas. A. monospermathecus Knöllner, 1935 is redescribed from France and Scotland. A. magnus sp.n., A. hrevis sp.n., A. curvipenis sp.n. and A. floridensis sp.n. are described from Italy, Brazil, France and Florida, respectively. Two very closely related forms are described from the Pacific: A. locyi sp.n. (California) and A. parviprostatus sp.n. (Great Barrier Reef). B. mediterranea sp.n. is described from Italy, and new European records are given forB. arclica Erséus, 1978 andfi. parvithecata Erséus, 1978. Both genera are characterized by having two pairs of prostate glands, well developed penes, and unpaired, mid-dorsal spermatheca (if present). The species of Bacescuella transfer their sperm by means of external spermatophores, structures that are not developed in Aktedrilus. The eight species of Aktedrilus are largely distinguished by means of the morphology of the spermatheca, penes and prostates. The four species of Bacescuella differ principally from each other in the length of the vasa deferentia, and in the morphology of the prostates and copulatory organs. Most Bacescuella species lack spermatheca.  相似文献   
56.

Determination of the optimal inoculation method and concentration to use for plant-bacteria interaction studies is important in many cases, such as the phytoremediation of heavy metals and other toxic compounds in contaminated areas. The aim of this study was to compare different concentrations and times of inoculation of Pseudomonas putida with various growth stages of Arabidopsis thaliana in 14-d in vitro cultures. A significant beneficial impact of the bacterium was detected in the shoot length and root weight of seedlings. The highest shoot length and root fresh and dry weights were detected in 14-d and 2 × 103 cfu mL−1 inoculated samples. In addition, the increase in root weight could be visualized with crystal violet staining, as relatively more root hair and lateral root formation occurred in seedlings inoculated with moderate concentrations of bacteria, possibly due to the ability of P. putida to produce indole-acetic acid. Moreover, the highest photosynthetic pigment accumulation was obtained with the highest bacterial inoculum (2 × 106 cfu mL−1), which was tested in 0- or 3-d-old seedlings. Rhizospheric bacterial colonization was also visualized with GFP-labeled bacteria by confocal microscopy. These results showed that biotization of A. thaliana with P. putida KT2440 did not cause severe oxidative stress in seedlings, because H2O2 accumulation levels together with CAT and POX activities were not significantly induced. Therefore, this strain could be used for several applications based on plant-bacteria interactions.

  相似文献   
57.
Molecular Biology Reports - Copy number variants (CNVs) play a key role in the etiology of autism spectrum disorder (ASD). Therefore, recent guidelines recommend chromosomal microarrays (CMAs) as...  相似文献   
58.
Molecular Biology Reports - Heat shock protein 90 (Hsp90) is a key chaperone that is abnormally expressed in cancer cells, and therefore, designing novel compounds to inhibit chaperone activities...  相似文献   
59.
60.
ABSTRACT

Cancer is a common cause of death worldwide. Approximately 80% of cancer patients use complementary or alternative medicines for treatment. Caffeic acid phenethyl ester (CAPE), the main active component of propolis, exhibits cytotoxic, antiproliferative and anti-cancer effects. Despite its anticancer effects CAPE exhibits no known harmful effects toward normal cells. We investigated the effects of CAPE on angiogenesis, apoptosis and oxidative stress using MDA MB-231, N2a and COLO 320 cell lines and CAPE treatments at 24 and 48 h. A two dimensional cell culture system was used and the findings were evaluated by an indirect immunohistochemical method and H-scores were calculated. CAPE was effective for all three cancer cell lines. After 24 and 48 h, we found a significant decrease in live cells and increased stress in the cells based on e-NOS and i-NOS levels.  相似文献   
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