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31.
A female patas monkey (Erythrocebus patas) housed with two males of different species, Hamadryas baboon (Papio hamadryas), and vervet monkey (Cercopithecus aethiops pigerythrus), gave birth to a female offspring in a semi-open enclosure on June 11, 1975. Karyological analyses and electrophoretic examinations were carried out in order to determine the real father of the hybrid. From the results of these observations it was concluded that the father of the hybrid individual wasCercopithecus aethiops. Additionally, somatometric and hematological investigations were performed.  相似文献   
32.
The two molecular forms of acethylcholinesterase (EC 3.1.1.7) in sea urchin embryos were characterized by several physical methods. The sedimentation coefficients determined by sucrose gradient centrifugation are 7.6S and 10.6S. The Stokes radii determined by gel filtration are 65 Å and 91 Å. From these parameters, molecular weights were estimated as 190,000 and 380,000; the one is twice as large as the other. Both forms have similar electric property and buoyant density in a CsCl gradient. When the enzyme solution was concentrated, the 10.6S form became predominant. These results suggest that the two forms are monomer and dimer. The sea urchin enzymes resemble globular forms of acetylcholinesterase of the electric organ of fishes. The activity of the enzyme abruptly increases in post-gastrulation embryos. Inhibition of concomitant protein synthesis by a specific inhibitor, emetine, does not affect the increase in enzyme activity. The result suggests that post-translational processes may be involved in the differentiation of this enzyme in sea urchin development. The following sea urchins were used in the study: Strongylocentrotus purpuratus, Strongylocentrotus franciscanus, and Dendraster excentricus.  相似文献   
33.
To clarify the reproductive state of male gorillas, we performed histological examinations on the testicles of 10 male gorillas (Gorilla gorilla). The testicular samples were obtained by autopsy, and ordinal histological preparations were made for light microscopy. The poor spermatogenesis of this species was characterized by the following findings: First, spermatogenesis was evident in only four samples. Meiosis progressed in two samples, but they lacked spermatogenesis. In the remaining four specimens, seminiferous tubules hyalinized without any sign of spermatogenesis. Second, seminiferous epithelia were thin even in the males in which spermatogenesis was observed. Third, degenerated seminiferous tubules were found in all specimens. Fourth, abnormally large syncytial cells were found in the tubules. Six stages in the epithelial cycle of the seminiferous tubules were identified. Testosterone staining made it clear that there were many Leydig cells with spherical or fusiform nuclei in an abundance of interstitial tissue. The relevance of the testicular architecture of gorillas to the mating system is discussed.  相似文献   
34.
BackgroundWe conducted a phase III study to evaluate S-1 as compared with UFT as control in patients after curative therapy for stage III, IVA, or IVB squamous-cell carcinoma of the head and neck (SCCHN).ResultsA total of 526 patients were enrolled, and 505 were eligible for analysis. The 3-year DFS rate was 60.0% in the UFT group and 64.1% in the S-1 group (HR, 0.87; 95%CI, 0.66-1.16; p = 0.34). The 3-year OS rate was 75.8% and 82.9%, respectively (HR, 0.64; 95% CI, 0.44-0.94; p = 0.022). Among grade 3 or higher adverse events, the incidences of leukopenia (5.2%), neutropenia (3.6%), thrombocytopenia (2.0%), and mucositis/stomatitis (2.4%) were significantly higher in the S-1 group.ConclusionsAlthough DFS did not differ significantly between the groups, OS was significantly better in the S-1 group than in the UFT group. S-1 is considered a treatment option after curative therapy for stage III, IVA, IVB SCCHN.

Trial Registration

ClinicalTrials.gov NCT00336947 http://clinicaltrials.gov/show/NCT00336947  相似文献   
35.
CS-0777 is a selective sphingosine 1-phosphate (S1P) receptor 1 modulator with potential benefits in the treatment of autoimmune diseases, including multiple sclerosis. CS-0777 is a prodrug that requires phosphorylation to an active S1P analog, similar to the first-in-class S1P receptor modulator FTY720 (fingolimod). We sought to identify the kinase(s) involved in phosphorylation of CS-0777, anticipating sphingosine kinase (SPHK) 1 or 2 as likely candidates. Unlike kinase activity for FTY720, which is found predominantly in platelets, CS-0777 kinase activity was found mainly in red blood cells (RBCs). N,N-Dimethylsphingosine, an inhibitor of SPHK1 and -2, did not inhibit CS-0777 kinase activity. We purified CS-0777 kinase activity from human RBCs by more than 10,000-fold using ammonium sulfate precipitation and successive chromatography steps, and we identified fructosamine 3-kinase (FN3K) and fructosamine 3-kinase-related protein (FN3K-RP) by mass spectrometry. Incubation of human RBC lysates with 1-deoxy-1-morpholinofructose, a competitive inhibitor of FN3K, inhibited ~10% of the kinase activity, suggesting FN3K-RP is the principal kinase responsible for activation of CS-0777 in blood. Lysates from HEK293 cells overexpressing FN3K or FN3K-RP resulted in phosphorylation of CS-0777 and structurally related molecules but showed little kinase activity for FTY720 and no kinase activity for sphingosine. Substrate preference was highly correlated among FN3K, FN3K-RP, and rat RBC lysates. FN3K and FN3K-RP are known to phosphorylate sugar moieties on glycosylated proteins, but this is the first report that these enzymes can phosphorylate hydrophobic xenobiotics. Identification of the kinases responsible for CS-0777 activation will permit a better understanding of the pharmacokinetics and pharmacodynamics of this promising new drug.  相似文献   
36.
We characterized a spontaneous dwarf mutant showing extremely short internodes and dark green leaves originating from azuki bean (Vigna angularis (Willd.) Ohwi & Ohashi) cultivar "Erimo-shouzu." F(1) plants of 3 cross combinations between the dwarf mutant and several representative wild-type plants, Erimo-shouzu, V. angularis accession Acc2265 and wild relative V. riukiuensis accession Acc2482, supported the dwarf genotype being recessive. In a total of 3328 F(2) progeny of these 3 crosses, 65 dwarfs (2.0%) and 5 chimeric dwarfs (0.2%) segregated and the remainder were wild-type plants (97.8%). In F(3) progeny derived from self-pollinated dwarf F(2) plants, we observed wild type (54.3%), dwarf (39.1%), and chimeric dwarf (6.5%) plants. Two types of chimeric plants were observed: dwarf branches on the axils of wild-type plant stems and wild-type branches on the axils of dwarf stems. In 21 dwarf F(2) plants, the dwarf trait cosegregated with simple sequence repeat marker CEDG154 on chromosome 4. Conversely, homozygote F(2) plants at this chromosomal segment from the dwarf mutant frequently (>90%) expressed the wild-type phenotype. We concluded that the dwarf phenotype is mitotically and meiotically inheritable and controlled by a single genetically unstable locus, designated Azuki Dwarf1 (AD1), which converts between 2 phenotypic states bidirectionally.  相似文献   
37.
A series of Sodium 4-[(4-butoxyphenyl)thio]-2'-substituted-1,1'-biphenyl-3- sulfonates were identified as functional sphingosine-1-phosphate (S1P) antagonists with selectivity for the S1P(1) receptor subtype starting from chemical lead 2, which was found while screening our in-house compound library. We performed chemical modifications on each regional structure of compound 2, for example, on the three ring compartments, the benzyl substituents, and the long alkyl chain part. The introduction of a biphenyl skeletal structure and the installation of a hydroxyl group onto the terminal carbon in the side-chain region resulted in the potent derivative 35c, which showed >500-fold more potent S1P(1) inhibitory activity than lead compound 2. We report herein the synthesis and structure-activity relationships of structurally novel S1P(1) receptor antagonists.  相似文献   
38.
Single nucleotide polymorphisms (SNPs) and insertions–deletions (InDels) are valuable molecular markers for molecular breeding among genetically closely related cultivars. Rice (Oryza sativa L. subsp. japonica) cultivars grown in Hokkaido (45–42°N), the northernmost region of rice paddy cultivation in Japan, have been bred for over 100 years for adaptation to low summer temperatures together with high yield and good eating quality. In this study, for 10 closely related rice cultivars released in Hokkaido and cultivar Koshihikari, we identified genome-wide SNPs and InDels by next-generation sequencing. More than 29 million reads from the Hokkaido cultivars, each 101 nucleotides long, were uniquely mapped to the Nipponbare reference genome. The average of the total nucleotide length of all uniquely mapped reads corresponded to 10.9 times (3,978 Mb with genome coverage of 90.7 %) the Nipponbare reference genome. An average of 99,955 putative SNPs (1.8 times the number in Koshihikari) and 14,617 putative InDels (also 1.8 times the number in Koshihikari) were detected in Hokkaido cultivars relative to the Nipponbare genome, which enabled analyses of the inheritance of pedigree haplotypes of four cultivars, SNPs and InDels among closely related Hokkaido cultivars, and haplotype blocks unique to Hokkaido cultivars. The comprehensive SNP and InDel data provide DNA marker resources and will facilitate quantitative trait locus analysis of biparental mapping of very closely related Hokkaido cultivars. Furthermore, the haplotype blocks unique to Hokkaido cultivars represent ideal genetic regions for improvement of cultivars to be grown near the northern and southern limits of rice cultivation.  相似文献   
39.
The roles of the proteins encoded by half-size adenosine triphosphate-binding cassette transporter subgroup G (ABCG) genes in abiotic stress responses are starting to be established in the dicot model Arabidopsis thaliana. In the monocot model rice, the functions of most half-size ABCG proteins in abiotic stress responses are unknown. Rcn1/OsABCG5 is an essential transporter for growth and development under abiotic stress, but its molecular function remains largely unclear. Here, we present a comprehensive overview of all 30 half-size ABCG genes in rice, including their gene structures, phylogeny, chromosome locations, and conserved motifs. Phylogenetic analysis revealed that the half-size OsABCG proteins were divided to four classes. All seven rice intronless genes, including Rcn1/OsABCG5, were in Class III, like the 12 intronless ABCG genes of Arabidopsis. The EST and FL-cDNA databases provided expression information for 25 OsABCG genes. Semi-quantitative and quantitative RT-PCR analyses demonstrated that seven OsABCG genes were up-regulated in seedlings, shoots or roots following treatments with abiotic stresses (6, 17, 42?°C, NaCl, or mannitol) and abscisic acid. Another 15 OsABCG genes were up-regulated under at least one of the abiotic stress conditions and other phytohormones besides abscisic acid. Hierarchical clustering analysis of gene expression profiles showed that expression of the OsABCG genes could be classified into four clusters. The Rcn1/OsABCG5 cluster was up-regulated by abscisic acid and included OsABCG2, 3, 13, and 27. The present study will provide a useful reference for further functional analysis of the ABCGs in monocots.  相似文献   
40.
We have already identified central neurons for cardioinhibition and cardioacceleration in Bathynomus, an isopod crustacean. The 1st thoracic ganglion (TG1) has cardioinhibitory neurons, which we call CIs, while the 2nd and 3rd thoracic ganglia (TG2 and TG3) have cardioacceleratory neurons, which we call CA1s and CA2s. We examined neuronal pathways for cardioinhibitory reflexes in whole animal preparations, using intracellular and extracellular recording methods. Cardiac inhibition in response to a variety of external stimuli was mediated by activation of CIs and inhibition of both CAs. When preparations had the ventral nerve cord intact, CIs were activated by excitatory postsynaptic potentials and CAs were inhibited by inhibitory postsynaptic potentials in response to tactile stimuli applied to sensilla setae on appendages and afferent stimuli applied to ganglionic roots of the thoracic ganglia. However, stimulation of ganglionic nerve roots of TG2 and TG3, or tactile stimulation of the body surface, failed to evoke inhibition of CAs in preparations in which both the cerebral ganglion and TG1 had been excised. These results suggest that TG1 is an indispensable central region for the excitation of CI and for inhibition of CA neurons, induced by tactile stimuli and by stimuli applied to nerve roots of TG2 and TG3.  相似文献   
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