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941.
The critically endangered Pangasianodon gigas is endemic to the Mekong River. Despite its importance, little is known about its genetic diversity and conservation efforts are hampered. Ten polymorphic dinucleotide microsatellite primer pairs were developed from DNA of P. gigas. The analysis of 20 individuals from hatchery stocks using these primers resulted in two to six alleles/locus; HO = 0.05–0.95; HE = 0.05–0.81. All but one locus (Pg‐3) conformed to Hardy–Weinberg expectation. Eight, six and seven primer pairs were amplified with the DNA from Pangasianodon hypophthalmus, Pangasius larnaudii and Pangasius sanitwongsei, respectively. These markers will be useful for genetic monitoring of wild and hatchery stocks of these pangasiids.  相似文献   
942.
Objective: To assess whether the rapid increase in obesity prevalence among persons with higher education levels observed in one U.S. study is also observed in a European adult population. Research Methods and Procedures: This study involved continuous surveillance of the adult population of Geneva, Switzerland (1993 to 2004), with annual random, independent, cross‐sectional, representative samples (6635 men and 6558 women, ages 35 to 74 years) and analysis of 12‐year trends in obesity prevalence across educational level subgroups. Results: Obesity prevalence in men had an upward trend in the medium education subgroup (p < 0.02), a borderline upward trend in the high education subgroup (p < 0.08), but no trend in the low education subgroup. There was a borderline trend interaction between the male low and medium education subgroups (p < 0.09). Obesity prevalence in women had a borderline increase in the low education subgroup (p < 0.08), an almost borderline increase in the high education subgroup (p = 0.11), but no significant trend in the medium education subgroup. There was no evidence of trend interaction between the female education groups. Discussion: In Geneva, as in the United States, the inverse association between education level and obesity rates has weakened over time among men, but, inconsistent with the U.S. findings, has persisted for women. Explanations may include more physically demanding occupations for men with low education levels and different attitudes toward body image between the sexes.  相似文献   
943.
小叶臭黄皮叶挥发油化学成分的研究   总被引:8,自引:0,他引:8  
纳智 《西北植物学报》2006,26(1):193-196
采用水蒸气蒸馏法提取小叶臭黄皮叶挥发油,运用毛细管气相色谱-质谱联用法对挥发油成分进行了分析,共分离出84个峰,鉴定了其中的66种成分,所鉴定成分占挥发油总量的94.52%.其主要化学成分为α-芹子烯(15.76%)、石竹烯(15.05%)、β-芹子烯(9.54%)、α-蒎烯(6.43%)和α-石竹烯(5.39%)等.  相似文献   
944.
945.
A series of heterocycle-containing oxindoles was synthesized and their HIV antiviral activities were assessed. Some of these analogs exhibited potent inhibitory activities against both wild-type virus and a number of drug-resistant mutant viruses. In addition, oxindole 9z also showed promising pharmacokinetics.  相似文献   
946.
Inhibition of the p38 map kinase pathway has been shown to be beneficial in the treatment of inflammatory diseases. The first class of potent p38 kinase inhibitors was the pyridinylimidazole compounds from SKB. Since then several pyridinylimidazole-based compounds have been shown to inhibit activated p38 kinase in vitro and in vivo. We have developed a novel series of pyridinylimidazole-based compounds, which potently inhibit the p38 pathway by binding to unactivated p38 kinase and only weakly inhibiting activated p38 kinase activity in vitro.  相似文献   
947.
Lipid rafts, membrane sub-domains enriched in sterols and sphingolipids, are controversial because demonstrations of rafts have often utilized fixed cells. We showed in living sperm that the ganglioside G(M1) localized to a micron-scale membrane sub-domain in the plasma membrane overlying the acrosome. We investigated four models proposed for membrane sub-domain maintenance. G(M1) segregation was maintained in live sperm incubated under non-capacitating conditions, and after sterol efflux, a membrane alteration necessary for capacitation. The complete lack of G(M1) diffusion to the post-acrosomal plasma membrane (PAPM) in live cells argued against the transient confinement zone model. However, within seconds after cessation of sperm motility, G(M1) dramatically redistributed several microns from the acrosomal sub-domain to the post-acrosomal, non-raft sub-domain. This redistribution was not accompanied by movement of sterols, and was induced by the pentameric cholera toxin subunit B (CTB). These data argued against a lipid-lipid interaction model for sub-domain maintenance. Although impossible to rule out a lipid shell model definitively, mice lacking caveolin-1 maintained segregation of both sterols and G(M1), arguing against a role for lipid shells surrounding caveolin-1 in sub-domain maintenance. Scanning electron microscopy of sperm freeze-dried without fixation identified cytoskeletal structures at the sub-domain boundary. Although drugs used to disrupt actin and intermediate filaments had no effect on the segregation of G(M1), we found that disulfide-bonded proteins played a significant role in sub-domain segregation. Together, these data provide an example of membrane sub-domains extreme in terms of size and stability of lipid segregation, and implicate a protein-based membrane compartmentation mechanism.  相似文献   
948.
In the methylerythritol phosphate pathway for isoprenoid biosynthesis, the GcpE/IspG enzyme catalyzes the conversion of 2-C-methyl-d-erythritol 2,4-cyclodiphosphate into (E)-4-hydroxy-3-methylbut-2-enyl diphosphate. This reaction requires a double one-electron transfer involving a [4Fe-4S] cluster. A thylakoid preparation from spinach chloroplasts was capable in the presence of light to act as sole electron donor for the plant GcpE Arabidopsis thaliana in the absence of any pyridine nucleotide. This is in sharp contrast with the bacterial Escherichia coli GcpE, which requires flavodoxin/flavodoxin reductase and NADPH as reducing system and represents the first proof that the electron flow from photosynthesis can directly act in phototrophic organisms as reducer in the 2-C-methyl-d-erythritol 4-phosphate pathway, most probably via ferredoxin, in the absence of any reducing cofactor. In the dark, the plant GcpE catalysis requires in addition of ferredoxin NADP(+)/ferredoxin oxido-reductase and NADPH as electron shuttle.  相似文献   
949.
In this study we identified snapin as an interaction partner of the CK1 isoform delta (CK1delta) in the yeast two-hybrid system and localized the interacting domains of both proteins. The interaction of CK1delta with snapin was confirmed by co-immunoprecipitation. Snapin was phosphorylated by CK1delta in vitro. Both proteins localized in close proximity in the perinuclear region, wherein snapin was found to associate with membranes of the Golgi apparatus. The identification of snapin as a new substrate of CK1delta points towards a possible function for CK1delta in modulating snapin specific functions.  相似文献   
950.
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