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71.
This article investigates the effect of dispute settlement decisions under the 1982 United Nations Convention on the Law of the Sea (UNCLOS) and whether and how states, particularly great powers, comply with these decisions. State practice suggests that an overwhelming majority of the decisions by UNCLOS dispute settlement bodies have been implemented. Significantly, not only small states but also the permanent members of the United Nations Security Council have complied with UNCLOS dispute settlement decisions even when they “lost” in the proceedings that were unilaterally initiated against them.  相似文献   
72.
Hydrocortisone was studied for its effect in vivo and in vitro on the phospholipids content and metabolism in the rat brain slices under conditions of their incubation in the medium with [2-14C]acetate. The seven-day administration of the preparation increases the specific radioactivity of sphingomyelin 2 times and that of phosphatidyl serine 2.3 times. The quantity of phosphatidic acid after the single administration of hydrocortisone decreases almost twice and its specific radioactivity (1 mg per 100 g of mass) increases two times. Under conditions of the preparation action in vitro the specific radioactivity of phosphatidyl inositol increases on the average five times. The 10(-4) M concentration of hydrocortisone in the medium makes the quantity of phosphatidic acid 1.4 times lower and the specific radioactivity of phosphatidyl-ethanol amine 1.9 times lower. Results of the study are discussed as related to the role of phospholipids in the processes of ionic transport and regulation of the genome activity.  相似文献   
73.
The immobilisation efficiency of the complexes of oligonucleotide/poly(L-lysine) on two polymeric carboxy-rich surfaces, i.e. poly(styrene/maleic acid) (PSMA) and poly(styrene/maleic anhydride) (PSMAA), has been investigated using X-ray photoelectron spectroscopy, atomic force microscopy (AFM) and fluorescence-based measurements of DNA attachment. A molecularly thin layer of either electrostatically or covalently (via amide bond) bound poly(L-lysine) allows the 'switching' from COOH-based to NH(2)-based surface functionality. The results indicate that approximately 54-57% and 55-62% of the applied oligonucleotides bind to polymeric surfaces via the route of electrostatic adsorption of poly(L-lysine) and covalent bonding of poly(L-lysine), respectively. This system can be applied conveniently for the detection of nucleic acids in both disposable and reusable biosensors.  相似文献   
74.
75.
We investigated the role of the cerebral cortex, particularly the face/tongue area of the primary sensorimotor (SMI) cortex (face/tongue) and supplementary motor area (SMA), in volitional swallowing by recording movement-related cortical potentials (MRCPs). MRCPs with swallowing and tongue protrusion were recorded from scalp electrodes in eight normal right-handed subjects and from implanted subdural electrodes in six epilepsy patients. The experiment by scalp EEG in normal subjects revealed that premovement Bereitschaftspotentials (BP) activity for swallowing was largest at the vertex and lateralized to either hemisphere in the central area. The experiment by epicortical EEG in patients confirmed that face/tongue SMI and SMA were commonly involved in swallowing and tongue protrusion with overlapping distribution and interindividual variability. BP amplitude showed no difference between swallowing and tongue movements, either at face/tongue SMI or at SMA, whereas postmovement potential (PMP) was significantly larger in tongue protrusion than in swallowing only at face/tongue SMI. BP occurred earlier in swallowing than in tongue protrusion. Comparison between face/tongue SMI and SMA did not show any difference with regard to BP and PMP amplitude or BP onset time in either task. The preparatory role of the cerebral cortex in swallowing was similar to that in tongue movement, except for earlier activation in swallowing. Postmovement processing of swallowing was lesser than that of tongue movement in face/tongue SMI; probably suggesting that the cerebral cortex does not play a significant role in postmovement processing of swallowing. SMA plays a supplementary role to face/tongue SMI both in swallowing and tongue movements.  相似文献   
76.
Here we report the cloning and functional characterization of eight members of the UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase gene family from Drosophila melanogaster (polypeptide GalNAc transferase = pgant1-8). Full-length cDNAs were isolated from a Drosophila embryonic library based on homology to known ppGaNTases. Alignments with characterized mammalian isoforms revealed strong sequence similarities between certain fly and mammalian isoforms, highlighting putative orthologues between the species. In vitro activity assays demonstrated biochemical transferase activity for each gene, with three isoforms requiring glycosylated substrates. Comparison of the activities of Drosophila and mammalian orthologues revealed conservation of substrate preferences against a panel of peptide and glycopeptide substrates. Furthermore, Edman degradation analysis demonstrated that preferred sites of GalNac addition were also conserved between certain fly and mammalian orthologues. Semi-quantitative PCR amplification of Drosophila cDNA revealed expression of most isoforms at each developmental stage, with some isoforms being less abundant at certain stages relative to others. In situ hybridization to Drosophila embryos revealed specific staining of pgant5 and pgant6 in the salivary glands and pgant5 in the developing hindgut. Additionally, pgant5 and pgant6 expression within the egg chamber was restricted to the follicle cells, cells known to be involved in egg formation and subsequent embryonic patterning. The characterization reported here provides additional insight into the use of this model system to dissect the biological role of this enzyme family in vivo during both fly and mammalian development.  相似文献   
77.
The study of the growth of the yeasts Rhodotorula rubra, Saccharomyces cerevisiae, and Debaryomyces vanriji at elevated temperatures and their survival after transient lethal heat shock showed that the ability of these yeasts to grow at supraoptimal temperatures (i.e., their thermoresistance) and their ability to tolerate lethal heat shocks (i.e., their thermotolerance) are determined by different mechanisms. The thermotolerance of the yeasts is suggested to be mainly determined by the division rate of cells before their exposure to heat shock.  相似文献   
78.
The investigation of the effect of the cytochrome oxidase inhibitors sodium cyanide and sodium azide on the thermotolerance of the yeasts Rhodotorula rubra, Debaryomyces vanriji, and Saccharomyces cerevisiae showed that these inhibitors diminish the thermotolerance of R. rubra and D. vanriji, but do not affect the thermotolerance of S. cerevisiae. Taking into account the fact that, unlike the latter yeast, R. rubra and D. vanriji are nonfermentative yeasts, the difference in the effects of the inhibitors on the yeast thermotolerance can be readily explained by the different types of glucose utilization (either oxidative or fermentative) in these yeasts. The data obtained also provide evidence that there is a correlation between the functional activity of mitochondria and the thermotolerance of yeast cells.  相似文献   
79.
We characterized radish lines from a genetic collection on the basis of six enzyme systems, identified genes controlling these enzymes, and examined joint inheritance of some biochemical and morphological traits.  相似文献   
80.
Beta-thalassemia major patients have chronic anemia and are dependent on blood transfusions to sustain life. Molecular characterization and prenatal diagnosis of beta3-thalassemia is essential in Malaysia because about 4.5% of the population are heterozygous carriers for beta-thalassemia. The high percentage of compound heterozygosity (47.62%) found in beta-thalassemia major patients in the Thalassaemia Registry, University of Malaya Medical Centre (UMMC), Malaysia, also supports a need for rapid, economical, and sensitive protocols for the detection of beta-thalassemia mutations. Molecular characterization of beta-thalassemia mutations in Malaysia is currently carried out using ARMS, which detects a single beta-thalassemia mutation per PCR reaction. We developed and evaluated Combine amplification refractory mutation system (C-ARMS) techniques for efficient molecular detection of two to three beta-thalassemia mutations in a single PCR reaction. Three C-ARMS protocols were evaluated and established for molecular characterization of common beta-thalassemia mutations in the Malay and Chinese ethnic groups in Malaysia. Two C-ARMS protocols (cd 41-42/IVSII #654 and -29/cd 71-72) detected the beta-thalassemia mutations in 74.98% of the Chinese patients studied. The CARMS for cd 41-42/IVSII #654 detected beta-thalassemia mutations in 72% of the Chinese families. C-ARMS for cd 41-42/IVSI #5/cd 17 allowed detection of beta-thalassemia mutations in 36.53% of beta-thalassemia in the Malay patients. C-ARMS for cd 41-42/IVSI #5/cd 17 detected beta-thalassemia in 45.54% of the Chinese patients. We conclude that C-ARMS with the ability to detect two to three mutations in a single reaction provides more rapid and cost-effective protocols for beta-thalassemia prenatal diagnosis and molecular analysis programs in Malaysia.  相似文献   
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