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31.
Nine species of marine algae have been assessed for the presence of novel hemagglutinins not extractable with buffer, unless the algal tissue was pretreated with Pronase. All species examined contained hemagglutinins, indicating the existence of a novel group of hemagglutinins which differed from those reported previously in marine algae.  相似文献   
32.
Random amplified polymorphic DNA (RAPD) markers were utilized for the identification of Lilium species and inter-specific hybrids. The optimum annealing temperature of the polymerase chain reaction (PCR) for the RAPD assay in Lilium was 54 °C, which is relatively higher than the temperature used for other genera reported by previous researchers. Among 76 primers used to amplify genomic DNA by PCR, 18 primers (24%) generated polymorphic DNA fragments in Lilium species and hybrids. Cultivars were also identified by RAPD markers. Some amplified fragments were unique to species of each section and to hybrids derived from these species; that is, they were the section-specific DNA markers. Sections, Sinomartagon, Leucolirion b, Leucolirion a and Archelirion could be identified by 6 section-specific markers amplified with five primers. Seven inter-section hybrids showed the section-specific bands of both parental sections, indicating that these markers would be useful for identifying the parental sections of inter-section hybrids.  相似文献   
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Abstract: Excitatory amino acid (EAA) neurotransmitters may play a role in the pathophysiology of traumatic injury to the CNS. Although NMDA receptor antagonists have been reported to have therapeutic efficacy in animal models of brain injury, these compounds may have unacceptable toxicity for clinical use. One alternative approach is to inhibit the release of EAAs following traumatic injury. The present study examined the effects of administration of a novel sodium channel blocker and EAA release inhibitor, BW1003C87, or the NMDA receptor-associated ion channel blocker magnesium chloride on cerebral edema formation following experimental brain injury in the rat. Animals (n = 33) were subjected to fluid percussion brain injury of moderate severity (2.3 atm) over the left parietal cortex. Fifteen minutes after injury, the animals received a constant infusion of BW1003C87 (10 mg/kg, i.v.), magnesium chloride (300 µmol/kg, i.v.), or saline over 15 min (2.75 ml/kg/15 min). In all animals, regional tissue water content in brain was assessed at 48 h after injury, using the wet weight/dry weight technique. In saline-treated control animals, fluid percussion brain injury produced significant regional brain edema in injured left parietal cortex ( p < 0.001), the cortical area adjacent to the site of maximal injury ( p < 0.001), left hippocampus ( p < 0.001), and left thalamus ( p = 0.02) at 48 h after brain injury. Administration of BW1003C87 15 min postinjury significantly reduced focal brain edema in the cortical area adjacent to the site of maximal injury ( p < 0.02) and left hippocampus ( p < 0.01), whereas magnesium chloride attenuated edema in left hippocampus ( p = 0.02). These results suggest that excitatory neurotransmission may play an important role in the pathogenesis of posttraumatic brain edema and that pre- or post-synaptic blockade of glutamate receptor systems may attenuate part of the deleterious sequelae of traumatic brain injury.  相似文献   
35.
We have purified DNA from gill tissue of a marine bivalve, Calyptogena soyoae, collected from the deep-sea cold seep communities in Sagami Bay, Japan. An rRNA gene was amplified, cloned, and sequenced. In situ hybridization revealed that the sequence is that of a bacterial endosymbiont within the gill of C. soyoae.  相似文献   
36.
Seven different restriction fragment length polymorphisms (RFLPs) at the N-acetylgalactosamine-6-sulfate sulfatase (GALNS) locus were analyzed using Southern blotting and polymerase chain reaction based techniques to search for the frequency of each RFLP produced by StyI, SphI, HaeIII, StuI, HapII, XhoI, and BamHI restriction endonucleases, respectively, in 36 mutant alleles, including two sibling cases and 100 normal alleles. Calculation of heterozygosity indexes showed that these RFLPs were polymorphic, ranging from 0.31 to 0.69 in mucopolysaccharidosis IVA (MPS IVA) patients compared with 0.21 to 0.65 in normal individuals. There was some significant difference in several RFLPs and in the combination with four kinds of RFLPs (SphI, StuI, HapII, XhoI polymorphisms). The normal alleles were composed of 13 different RFLPs haplotypes; the most common among the Japanese population carrying normal alleles was haplotype 8 (bDEF1) (31.3%), the others being dispersed. The same haplotype 8 was the most frequent in the mutant alleles (44.4%), with seven further haplotypes. These findings revealed the striking variety of polymorphic haplotypes in the MPS IVA gene. By using these five kinds of RFLPs, we examined the theoretical informativity of haplotype analysis in heterozygote detection in nine unrelated MPS IVA families and ten unrelated normal families. All the members of the MPS IVA families studied were diagnosed as a patient, carrier, or noncarrier. We propose that prenatal diagnosis or family analysis in cases in which mutations have not been characterized is now feasible.  相似文献   
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In a previous study, various intermediates in λ DNA packaging were visualized after lysis of λ-infected cells with osmotic shock and sedimentation through a sucrose formalin cushion onto electron microscope grids. Along this line, a systematic screening for intermediates accumulated in all head mutants available was performed. λA?-infected cells accumulate only empty spherical protein shells (petit λ) bound at an intermediate point along the DNA thread. In situ digestion experiments with restriction endonuclease EcoRI show that the petit λ-DNA complexes are formed at a fixed point on the DNA concatemer. In λNu1?-infected cells, however, most petit λ was not bound to DNA. In Fec? cells, which are defective in formation of concatemers but normal in head protein synthesis, most petit λ did not sediment onto the carbon film of the grid. In D? mutant, petit λ, partially full heads and empty heads with released DNA were observed. λFI?-infected cells also accumulate petit λ and partially full heads. The present studies suggest that protein pNu1 is required for complex formation between head precursors and DNA concatemers, pA for the initiation of DNA packaging, pD and pFI for the promotion of DNA packaging, and pD for stabilization of head structures. The results obtained with other head mutants involved in formation of mature proheads and head completion confirm earlier results obtained by different techniques.  相似文献   
39.
Some common properties of lectins from marine algae   总被引:10,自引:1,他引:9  
Hori  Kanji  Miyazawa  Keisuke  Ito  Keiji 《Hydrobiologia》1990,(1):561-566
Twelve kinds of lectins isolated from four species of marine algae, Boodlea coacta (Chlorophyta) and Hypnea japonica, Carpopeltis flabellata and Solieria robusta (Rhodophyta), were compared for their chemical and biological properties. These lectins were proteins or glycoproteins, similar to terrestrial plant lectins. However, unlike most terrestrial plant lectins, they had a small molecular size (4,200 to 25,000 daltons), were mostly monomeric, and had no affinity for monosaccharides. They strongly agglutinated trypsin-treated rabbit erythrocytes, and their activities commonly were inhibited by glycoproteins bearing N-glycans. From hemagglutination-inhibition tests with various glycoproteins and related compounds, it was found that B. coacta lectins recognize high-mannose N-glycans; H. japonica lectins complex N-glycans, and C. flabellata and S. robusta lectins recognize both types of N-glycans.  相似文献   
40.
Abstract: This paper describes a new, sensitive assay for dopamine-β-hydroxylase (DBH) activity in human cerebrospinal fluid (CSF), serum and brain tissues by high performance liquid chromatography (HPLC) with electrochemical detection (ED). Dopamine (DA) was used as a substrate and was incubated under optimal conditions. Norepinephrine (NE) formed enzymatically from DA was isolated by a double-column procedure, the first column of Dowex-50-H+ and the second column of aluminum oxide. NE was adsorbed on the second aluminum oxide column and then eluted with 0.5 M-hydrochloric acid and assayed by HPLC-ED. Epinephrine (EN) was added to each incubation mixture as an internal standard, and this assay was therefore highly reproducible. The peak height in HPLC was linear from 500 fmol to 100 pmol of NE and EN. The lower limit of detection for NE formed enzymatically was about 30 pmol, which indicated that the sensitivity of this procedure was comparable to that of radioassay procedures. We applied the method to measurement of the activity of and examination of some of the characteristics of DBH in human CSF. DBH activity in CSF of Parkinsonian patients was lower than that of control patients. The properties of DBH in human CSF were similar to those in serum and adrenal medulla.  相似文献   
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