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101.
Songtao Guo Weihong Ji Ming Li Hongli Chang Baoguo Li 《American journal of primatology》2010,72(1):25-32
This article reports the first genetic study of the mating system of the Sichuan snub‐nosed monkey (Rhinopithecus roxellana), an endemic and endangered species in China. The investigation was carried out in a population (WRT) in the Qinling Mountains using data from both field observation and paternity analysis through microsatellite DNA profiling. During a mating season, a male on an average copulated with 5.7 females. Approximately 18% of the females were observed to copulate with more than one male over the study period. The majority of copulations (94.5%) were initiated by females. Twenty‐eight of 430 observed matings were extra‐unit copulations. Eight polymorphic microsatellite loci were used for paternity analysis. The number of alleles at each locus ranged from 3 to 7 (mean=4.3). Observed heterozygosity ranged between 0.32 and 0.79. None of the loci showed significant deviation from Hardy–Weinberg equilibrium. Results from paternity exclusion showed that 12 of 21 (57.1%) immature individuals were sired by extra‐unit males. Although the basic social unit of snub‐nosed monkeys is consistent with a polygynous mating system, both field observation and genetic data suggests that their mating system is polygamous. Infanticide and inbreeding avoidance are the most likely explanations for the promiscuity of female snub‐nosed monkeys. Am. J. Primatol. 72:25–32, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
102.
A cell-detaching reactor was developed to collect cells growing on microcarriers for inoculation between stepwise-expanded
bioreactors. It consisted of a trypsinization zone and a separation zone, which were separated by a 200-mesh stainless steel
screen. The screen allowed the cells only to pass through to the next bioreactor, after the cells have been trypsinized and
detached from microcarriers. The operating feasibility of the cell-detaching reactor was tested with anchorage-dependent recombinant
Chinese hamster ovary (rCHO) and African green monkey kidney (Vero) cells. rCHO and Vero cells were first cultured in a small
microcarrier bioreactor, and then inoculated via the cell-detaching reactor into either a packed-bed bioreactor (for rCHO
cells) or a larger microcarrier bioreactor (for Vero cells). For rCHO cells, the cell density reached 1.3 × 107 cells/ml in the perfusion culture, and Vero cells reached 1.3 × 106 cells/ml in the batch culture. 相似文献
103.
Murai T Mohamed M Bernard H Mahedi PA Saburi R Higashi S 《Primates; journal of primatology》2007,48(2):117-121
Successful or unsuccessful female transfers were observed seven times during a 32-month field study of proboscis monkeys (Nasalis larvatus) inhabiting a riverine forest along a tributary of the Kinabatangan River, Sabah, Malaysia. In all cases, the females voluntarily
left their own groups and immediately joined with another one. When adult females tried to shift to other groups, adult males
called them back to their own groups, but appeared to be indifferent to subadult females. When the adult females returned,
the males never attacked the females physically, but instead often emitted herding sounds to them. One subadult female was
repelled by a resident adult female. When one adult female transferred into a new one-male group, she left her behind son
in an all-male group. The number of females often fluctuated in most study groups, with this fluctuation being more prominent
among subadult females than adult females. It is likely that female transfer in proboscis monkeys is not a rare occurrence
and that it is especially common among sub-adult females. 相似文献
104.
Zábranská H Tůma R Kluh I Svatos A Ruml T Hrabal R Pichová I 《Journal of molecular biology》2007,365(5):1493-1504
Retroviral proteases are translated as a part of Gag-related polyproteins, and are released and activated during particle release. Mason-Pfizer monkey virus (M-PMV) Gag polyproteins assemble into immature capsids within the cytoplasm of the host cells; however, their processing occurs only after transport to the plasma membrane and subsequent release. Thus, the activity of M-PMV protease is expected to be highly regulated during the replication cycle. It has been proposed that reversible oxidation of protease cysteine residues might be responsible for such regulation. We show that cysteine residues in M-PMV protease can form an intramolecular S-S bridge. The disulfide bridge shifts the monomer/dimer equilibrium in favor of the dimer, and increases the proteolytic activity significantly. To investigate the role of this disulfide bridge in virus maturation and replication, we engineered an M-PMV clone in which both protease cysteine residues were replaced by alanine (M-PMV(PRC7A/C106A)). Surprisingly, the cysteine residues were dispensable for Gag polyprotein processing within the virus, indicating that even low levels of protease activity are sufficient for polyprotein processing during maturation. However, the long-term infectivity of M-PMV(PRC7A/C106A) was noticeably compromised. These results show clearly that the proposed redox mechanism does not rely solely on the formation of the stabilizing S-S bridge in the protease. Thus, in addition to the protease disulfide bridge, reversible oxidation of cysteine and/or methionine residues in other domains of the Gag polyprotein or in related cellular proteins must be involved in the regulation of maturation. 相似文献
105.
106.
对恒河猴进行二次接种H5N1亚型禽流感病毒试验,并对二次接毒的结果进行观察,评估初次接毒对恒河猴二次接毒效果的影响.首次接种试验中,3、4、5号恒河猴用环甲膜穿刺注射方法接种含有H5N1亚型禽流感病毒的尿囊液,6号猴接种不含病毒的尿囊液.90d后,再次用环甲膜穿刺注射方法二次接种,4、5、6号猴接种7mlTCID50浓度为104.875病毒的尿囊液,3号猴接种7ml不含病毒的尿囊液.进行抗体等检测,并分别于72h无痛处死3、4、6号猴,第7d无痛处死5号猴,进行肺的病毒检测及病理观察.结果显示,3、4、5号猴至试验结束时体内依然有较高的抗H5N1亚型禽流感病毒抗体水平,6号猴没有抗体;通过RT-PCR以及免疫组化染色进行病毒检测,均只在6号猴肺部检出病毒,且6号猴肺部病理损伤最为严重.由此可以得出初步结论:在初次感染H5N1亚型禽流感病毒后90d,临床症状已基本恢复正常的恒河猴体内仍然有较高水平的抗体,此时,恒河猴抵抗H5N1亚型禽流感病毒二次感染的能力显著提高. 相似文献
107.
Before and below 'theory of mind': embodied simulation and the neural correlates of social cognition 总被引:11,自引:0,他引:11
Gallese V 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2007,362(1480):659-669
The automatic translation of folk psychology into newly formed brain modules specifically dedicated to mind-reading and other social cognitive abilities should be carefully scrutinized. Searching for the brain location of intentions, beliefs and desires-as such-might not be the best epistemic strategy to disclose what social cognition really is. The results of neurocognitive research suggest that in the brain of primates, mirror neurons, and more generally the premotor system, play a major role in several aspects of social cognition, from action and intention understanding to language processing. This evidence is presented and discussed within the theoretical frame of an embodied simulation account of social cognition. Embodied simulation and the mirror neuron system underpinning it provide the means to share communicative intentions, meaning and reference, thus granting the parity requirements of social communication. 相似文献
108.
109.
110.
Ju HQ Xiang YF Xin BJ Pei Y Lu JX Wang QL Xia M Qian CW Ren Z Wang SY Wang YF Xing GW 《Bioorganic & medicinal chemistry letters》2011,21(6):1675-1677
In this study, a novel Hsp90 inhibitor BJ-B11, was synthesized and evaluated for in vitro antiviral activity against several viruses. Possible anti-HSV-1 mechanisms were also investigated. BJ-B11 displayed no antiviral activity against coxsackievirus B3 (CVB3), human respiratory syncytial virus (RSV) and influenza virus (H1N1), but exhibited potent anti-HSV-1 and HSV-2 activity with EC50 values of 0.42 ± 0.18 μM and 0.60 ± 0.21 μM, respectively. Additionally, the inhibitory effects of BJ-B11 against HSV-1 were likely to be introduced at early stage of infection. Our results indicate that BJ-B11 with alternative mechanisms of action is potent as an anti-HSV clinical trial candidate. 相似文献