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361.
362.
Yuzuru Hamada Nontakorn Urasopon Islamul Hadi Suchinda Malaivijitnond 《International journal of primatology》2006,27(2):497-513
Rhesus (Macaca mulatta) and long-tailed (M. fascicularis) macaques belong to the same species, and are parapatric within a
zone that lies between 15° and 20° N on the Indochinese peninsula. Researchers have reported probable hybrids between the
2 species from that zone, but have not studied the extent of introgression. To test for phenotypic evidence of hybridization,
we collected body mass, morphometrics (body size and proportions), and pelage color readings from free-ranging rhesus living
close to the zonal boundary at Wat Tham Pa Mak Ho (WTPMH), Wang Saphun district, Loei province, northeastern Thailand (17°14′N,
101°47′E). Female WTPMH rhesus macaques (n =12) were 10–20% smaller, but with a greater relative tail length than the captive
Chinese or Indian female rhesus. Female WTPMH were larger than the free-ranging long-tailed macaques, but with similar limb
proportions and a shorter relative tail length. The WTPMH rhesus macaques also displayed the bipartite pelage color pattern
typical of Macaca mulatta . The evidence suggests slight contribution of long-tailed macaques to the gene pool of the WTPMH
population. Further sampling of other macaque populations within the zone and genetic analysis are essential to address better
the question of hybridization. Determination of the distribution and range of biobehavioral variation of macaques within the
zone is urgently needed, because their habitat is being rapidly destroyed by deforestation, and their demography and social
structure are threatened by artificial disturbance. 相似文献
363.
364.
The cellular response to Leishmania major (L. major) is usually evaluated in vivo by the delayed-type-hypersensitivity (DTH) test using leishmanin. Leishmanin can give false-positive reactions in areas where there is a background of leishmaniasis. In a previous study, it was shown that a 56 kDa antigen purified from promastigote and culture supernatant of L. major induce strong DTH reactions in sensitized guinea pigs. In this study, the species-specificity of this antigen was further investigated. Three groups of guinea pigs were sensitized with L. major, L. tropica, and L. infantum and both flanks of sensitized animal were injected intradermally with purified 56 kDa antigen or soluble leishmania antigen (SLA). The extent of indurations were measured after 24, 48, and 72 h. In animals which were sensitized with three species of leishmania, only those immunized with L. major showed skin reactions to purified antigen by an increase in skin thickness. Since complex antigen mixtures such as SLA and leishmanin show cross-reactivity and can be non-specific, the result obtained here suggest that 56 kDa antigen may be a useful diagnostic tool for species specific diagnosis in field studies of leishmaniasis. 相似文献
365.
Recurrent insertion and duplication generate networks of transposable element sequences in the Drosophila melanogaster genome 总被引:2,自引:0,他引:2
Background
The recent availability of genome sequences has provided unparalleled insights into the broad-scale patterns of transposable element (TE) sequences in eukaryotic genomes. Nevertheless, the difficulties that TEs pose for genome assembly and annotation have prevented detailed, quantitative inferences about the contribution of TEs to genomes sequences. 相似文献366.
The spermatozoa of most fish species are immotile in the testis and seminal plasma. Therefore, motility is induced after the spermatozoa are released into the aqueous environment during natural reproduction or into the diluent during artificial reproduction. There are clear relationships between seminal plasma composition and osmolality and the duration of fish sperm motility. Various parameters such as ion concentrations (K+, Na+, and Ca2+), osmotic pressure, pH, temperature and dilution rate affect motility. In the present paper, we review the roles of these ions on sperm motility in Salmonidae, Cyprinidae, Acipenseridae and marine fishes, and their relationship with seminal plasma composition. Results in the literature show that: 1. K+ is a key ion controlling sperm motility in Salmonidae and Acipenseridae in combination with osmotic pressure; this control is more simple in other fish species: sperm motility is prevented when the osmotic pressure is high (Cyprinidae) or low (marine fishes) compared to that of the seminal fluid. 2. Cations (mostly divalent, such as Ca2+) are antagonistic with the inhibitory effect of K+ on sperm motility. 3. In many species, Ca2+ influx and K+ or Na+ efflux through specific ionic channels change the membrane potential and eventually lead to an increase in cAMP concentration in the cell, which constitutes the initiation signal for sperm motility in Salmonidae. 4. Media that are hyper- and hypo-osmotic relative to seminal fluid trigger sperm motility in marine and freshwater fishes, respectively. 5. The motility of fish spermatozoa is controlled through their sensitivity to osmolality and ion concentrations. This phenomenon is related to ionic channel activities in the membrane and governs the motility mechanisms of axonemes. 相似文献
367.
368.
M Filippini W Qi S Jaenicke A Goesmann TH Smits HC Bagheri 《Journal of bacteriology》2012,194(16):4445
Fibrisoma limi strain BUZ 3(T), a Gram-negative bacterium, was isolated from coastal mud from the North Sea (Fedderwardersiel, Germany) and characterized using a polyphasic approach in 2011. The genome consists of a chromosome of about 7.5 Mb and three plasmids. 相似文献
369.
Shahryar Semnani Gholamreza Roshandel Azadehsadat Zendehbad Abbasali Keshtkar Hadi Rahimzadeh Nafiseh Abdolahi Sima Besharat Abdolvahab Moradi Honeyehsadat Mirkarimi Seyedzinab Hasheminasab 《Journal of trace elements in medicine and biology》2010,24(3):174-177
ProjectGolestan province, located in northeast of Iran, has been known as a high risk area for esophageal cancer (EC). This study was conducted to assess the relationship between soils selenium (Se) level and development of EC in this region.ProceduresIn this ecological study, 135 blocks were identified in Golestan province based on geographical altitude and longitude on the map. One soil sample was collected from the center of each block. Then we investigated Se concentration in soil samples by flame atomic absorption spectrometry. Statistical analysis was performed by the Pearson correlation test and Student t-tests. P-values of less than 0.05 were considered as significant.ResultsThe mean±SD of soils Se level in Golestan province was 3.7±1.61 mg/kg. There was a positive correlation between soils Se level and EC rates in this area (P=0.03) (Pearson correlation coefficient=0.19). Soils Se concentration was significantly higher in high (4.13 mg/kg) than in the low (3.39 mg/kg) EC rate areas (P=0.01).ConclusionsWe found high soils Se concentration and a significant positive relationship between soils Se level and EC rate in Golestan province of Iran. So, high soils Se level may play a possible role in developing EC in this area, specifically in Turkmensahra (very high EC rates). 相似文献
370.
Hadi Poerwono Shigeru Sasaki Yoshiyuki Hattori Kimio Higashiyama 《Bioorganic & medicinal chemistry letters》2010,20(7):2086-2089
Pinostrobin (5-hydroxy-7-methoxyflavanone) obtained in relatively large amounts from fingerroot (Boesenbergia pandurata) was converted to its C-6 and C-8 prenylated derivatives. The Mitsunobu reaction, europium(III)-catalyzed Claisen–Cope rearrangement, and Claisen reaction coupled with cross-metathesis were used as the key steps. Using a sealed-vessel microwave reactor, the Mitsunobu and Claisen/Cope reactions occurred smoothly with short reaction times and in satisfactory yields. The target compounds and five new intermediary substances showed cytotoxic activity toward SK-BR-3, MCF-7, PC-3, and Colo-320DM human tumor cell lines, and all of them had significantly lower IC50 (μM) values than pinostrobin. 相似文献