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991.
992.
Hong KW Iwatsuki H Takenaka O Hayasaka I Murayama Y Ito S Inoue-Murayama M 《Primates; journal of primatology》2007,48(2):151-155
Polymorphic microsatellite repeats in the promoter region of estrogen receptor α gene (ESRα and the intron 6 region of estrogen receptor β gene (ESRβ) have been reported in human populations. To examine the evolutional state of both repeats, we surveyed the corresponding
regions in DNA sequences from the following great apes and gibbons: 56 chimpanzees, 3 bonobos, 16 gorillas, 20 orangutans
and 60 gibbons (four species: 17 of Hylobates agilis, 11 of H. lar, 15 of H. muelleri, and 17 of H. syndactylus). In the corresponding region of the TA repeat of human ESRα, chimpanzees and bonobos had two motifs in the repeat tract, (TA)7–9 and (CA)4–6. Gorillas had the (TA)9–10 repeat tracts and orangutans had monomorphic (TA)7 repeats. Although all great apes maintained the TA expansion, all gibbon sequences contained (TA)2, implying that the CA dinucleotide expansion arose in the ancestor of chimpanzees and bonobos. The nucleotide sequences of
ESRβ showed a very complex repeat pattern in apes. The human sequences had a non-variable preceding sequence at (CA)
n
, (GA)2(TA)8(CA)4(TA). In apes that region included {(TA)
n
(CA)
n
}
n
. Gibbon sequences included (TATG)
n
and (TATC)
n
and no regular construction was observed. A deletion event in the reverse primer site seems to have occurred in the orangutan
lineage. In addition, a great diversity of allele length was detected in each gibbon species. 相似文献
993.
Diurnal changes of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPCO) activity and its content were measured to find
the mechanism of RuBPCO activity regulation in Norway spruce needles. Both initial and total RuBPCO activities as well as
the activation state had a typical pattern with two peaks in the morning and afternoon, respectively, and a midday depression.
On the 19 October, RuBPCO content decreased during the day from 3.1 to 1.4 g m−2, while on the 20 October it was approximately constant both in the morning and in the afternoon (2.7 g m−2). Neither initial nor total activity of RuBPCO copied irradiances. Relatively low morning and evening values of total activities
indicate that nocturnal inhibitor CA1P is important in Norway spruce. However, the midday depression of total activity indicates
that besides CA1P there function some other inhibitors of RuBPCO. In addition, the diminution of RuBPCO content during the
day may indicate repression of its gene expression. 相似文献
994.
995.
996.
Essential‐Oil Composition of the Needles Collected from Natural Populations of Macedonian Pine (Pinus peuce Griseb.) from the Scardo‐Pindic Mountain System 下载免费PDF全文
Biljana Nikolić Mihailo Ristić Srdjan Bojović Vlado Matevski Zoran Krivošej Petar D. Marin 《化学与生物多样性》2014,11(6):934-948
The needle‐terpene profiles of two natural Pinus peuce populations from the Scardo‐Pindic mountain system (Mt. O?ljak and Mt. Pelister) were analyzed. Among the 90 detected compounds, 87 were identified. The dominant constituents were α‐pinene (45.5%), germacrene D (11.1%), β‐pinene (10.8%), and camphene (10.3%). The following eight additional components were found to be present in medium‐to‐high amounts (0.5–10%): bornyl acetate (5.0%), β‐phellandrene (3.4%), β‐caryophyllene (2.9%), β‐myrcene (0.9%), germacrene D‐4‐ol (0.9%), tricyclene (0.7%), (E)‐hex‐2‐enal (0.7%), and bicyclogermacrene (0.6%). Although the general needle‐terpene profiles of the populations from Mt. O?ljak and Mt. Pelister were found to be similar to those of the populations from Zeletin, Sjekirica, and Mokra Gora (Dinaric Alps), principle component analysis (PCA) of eight terpenes (α‐pinene, β‐myrcene, α‐terpinolene, bornyl acetate, α‐terpinyl acetate, β‐caryophyllene, trans‐β‐farnesene, and germacrene D) in 139 tree samples suggested a divergence between the two population groups, i.e., the samples from the Scardo‐Pindic mountain system and those from the Dinaric Alps. Genetic analysis of the β‐pinene content demonstrated a partial divergence between the two geographical groups. The profiles of both population groups differed from those published for populations from the Balkan‐Rhodope mountains system (literature results), which were characterized by high contents of bornyl acetate and citronellol (Greek populations) or δ‐car‐3‐ene (Bulgarian populations). 相似文献
997.
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has emerged as a reliable tool for fast identification and classification of microorganisms. In this regard, it represents a strong challenge to microscopic and molecular biology methods. Nowadays, commercial MALDI systems are accessible for biological research work as well as for diagnostic applications in clinical medicine, biotechnology and industry. They are employed namely in bacterial biotyping but numerous experimental strategies have also been developed for the analysis of fungi, which is the topic of the present review. Members of many fungal genera such as Aspergillus, Fusarium, Penicillium or Trichoderma and also various yeasts from clinical samples (e.g. Candida albicans) have been successfully identified by MALDI-TOF MS. However, there is no versatile method for fungi currently available even though the use of only a limited number of matrix compounds has been reported. Either intact cell/spore MALDI-TOF MS is chosen or an extraction of surface proteins is performed and then the resulting extract is measured. Biotrophic fungal phytopathogens can be identified via a direct acquisition of MALDI-TOF mass spectra e.g. from infected plant organs contaminated by fungal spores. Mass spectrometric peptide/protein profiles of fungi display peaks in the m/z region of 1000–20 000, where a unique set of biomarker ions may appear facilitating a differentiation of samples at the level of genus, species or strain. This is done with the help of a processing software and spectral database of reference strains, which should preferably be constructed under the same standardized experimental conditions. 相似文献
998.
Cell suspension cultures of Silybum marianum are able to excrete silymarin compounds into the medium upon elicitation with methyl jasmonate or cyclodextrins. Knowledge of transport mechanism is important to understand Sm metabolism and to develop strategies aimed at increasing production by means of cell cultures. For these reasons, a pharmacological approach was undertaken in this work in order to elucidate the possible mechanism involved in the release of this class of secondary metabolites into the extracellular medium of suspensions. 相似文献
999.
本研究的目的在于探讨产前应激对子代大鼠海马CA3神经元高电压激活(HVA)钙通道、延迟整流钾电流(delayedrectifierpotassiumcurrents,IKD)的影响。产前应激(prenatalstress,PNS)组孕鼠孕晚期给予束缚应激,应用全细胞膜片钳技术进行研究。结果显示产前应激增加了子代海马CA3神经元HVA钙通道峰电流幅值,对照组和产前应激组子代CA3神经元平均最大HVA钙电流峰值分别为-576.52±7.03pA和-702.05±6.82pA(P<0.01)。同时未改变其电导-电压关系,也未改变延迟整流钾通道电流-电压关系、电导-电压关系。结果提示,在胎儿发育的关键时期,给予母体产前应激,引起子代海马神经元HVA钙电流增加,其机制一方面PNS导致皮质酮升高,从而可能增加HVA钙通道mRNA表达;另一方面PNS所致反应性氧化产物(reactiveoxygenspecies,ROS)增多,后者可能通过磷酸化HVACa2 通道亚单位,从而提高HVA钙电流幅值。 相似文献
1000.
Tejada-Simon MV Villasana LE Serrano F Klann E 《Biochemical and biophysical research communications》2006,343(2):504-512
Neuronal development requires several discrete morphological steps that are believed to involve the small GTPase Rac. For example, neural activity, through NMDA receptors and/or AMPA receptors, activates Rac leading to elaboration of dendritic arbors. In the current study, we have conducted studies which indicate that Rac might be an important molecule involved in morphological plasticity in the adult mouse. We demonstrate that Rac is expressed at synapses in the adult mouse hippocampus. We also demonstrate that treatment of hippocampal slices with NMDA induces membrane translocation and activation of Rac in area CA1. Interestingly, we also find that there is an increase in Rac that is associated with NMDA receptor complexes following NMDA receptor activation. Taken together, our data are consistent with the idea that Rac could be participating in NMDA receptor-dependent changes in morphology that occur during synaptic plasticity and memory formation in the adult mouse hippocampus. 相似文献