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91.
AIM: To investigate the effects of lenalidomide alone or combined with bortezomib on induction of apoptosis in multiple myeloma(MM) KM3 cells.METHODS: The KM3 cells were treated with lenalidomide alone or combined with bortezomib. The number of viable cells was determined by trypan blue exclusion. Apoptotic cells were simultaneously stained with annexin V-FITC and PI and determined by flow cytometry. RT-PCR was used to examine the level of p65 mRNA. Western blotting was used to examine the protein levels of P65, pP65, caspase-3,-8, -9, and poly (ADP-ribose) polymerase (PARP). RESULTS: Lenalidomide-inhibited the cell growth and induced apoptosis of KM3 cells. The mechanism responsible for lenalidomide-mediated inhibition was via NF-κB and activation of caspase-mediated induction of apoptosis. A synergistic effect was observed when combination of lenalidomide with bortezomib was used. CONCLUSION: Lenalidomide inhibits the growth and induces apoptosis in KM3 cells. There is a synergistical effect when combination of lenalidomide with bortezomib is in use.  相似文献   
92.
In the Coral Triangle community-based marine protected areas (MPAs) are being established at a prolific rate. Their establishment can benefit both fisheries and biodiversity, and they provide both a socially and economically acceptable means of managing coral reefs in developing nations. However, because such MPAs are typically small (usually <0.5 km2), they will rarely provide protection to large mobile fishes. An exception to this limitation may exist when community-based MPAs are established to protect small sites where vital processes occur, such as fish spawning aggregations (FSAs). To test the effectiveness of small (0.1–0.2 km2) MPAs for protecting FSAs, we monitored three FSA sites where brown-marbled grouper (Epinephelus fuscoguttatus), camouflage grouper (Epinephelus polyphekadion) and squaretail coralgrouper (Plectropomus areolatus) aggregate to spawn. Sites were monitored during peak reproductive periods (several days prior to each new moon) between January 2005 and November 2009. All three sites are located in New Ireland Province, Papua New Guinea, and had been exploited for decades, but in 2004 two sites were protected by the establishment of community-based MPAs. The third site continued to be exploited. Over the monitoring period densities of E. fuscoguttatus and E. polyphekadion increased at both MPAs, but not at the site that remained open to fishing. At one MPA the densities of E. polyphekadion increased tenfold. Our findings demonstrate that community-based MPAs that are appropriately designed and adequately enforced can lead to the recovery of populations of vulnerable species that aggregate to spawn.  相似文献   
93.
Mycorrhizal fungi may simultaneously associate with multiple plant hosts, and the implications of this for the fungi involved are not well understood. To address this question, two arbuscular mycorrhizal fungi (AMF), Glomus clairoideum (a treatment referred to as “Glo”) and Scutellospora fulgida (a treatment referred to as “Scut”), were grown separately in pots that each consisted of two plant compartments separated by a root-free-compartment (RFC). Fungi within each two-plant-compartment pot were exposed to either two individuals of indiangrass (Sorghastrum nutans), two individuals of big bluestem (Andropogon gerardii), or one of each. A non-inoculated treatment (“Non”) was included to help gauge the potential influence of greenhouse contaminant fungi, cross-contamination, or any misidentification of non-AMF hyphae. The two host species had additive effects on the growth of AM hyphae in plant compartments of Scut, Glo, and Non pots, and in the RFCs of Scut pots. In Glo RFCs, however, they were antagonistic in their effects. Synergism between hosts in Non RFCs suggested that any potential contaminants or misidentification could not explain this result. Underyielding was not seen in shoot weight, root weight, or root length in dual host pots, and also therefore could not explain the result. Hyphal growth in the Scut treatment was evenly distributed between the RFC and plant compartments (or marginally skewed toward the RFC), while hyphal growth in the Glo treatment was skewed toward plant compartments (nearer roots). However, hyphal lengths were more highly correlated across plant compartments within a common pot in the Glo treatment, suggesting that this AMF bridged the RFC to experience the entire two-host pot as a single environment to a greater extent than Scut did. These AMF differed in how they responded to both the species composition of the two-host environment and its spatial structure; potential implications for mycorrhizal community dynamics are discussed.  相似文献   
94.
Recent advances in molecular techniques have allowed for the routine examination of nucleic acids in environmental samples. Although current methodologies are very sensitive, accurate target DNA quantification from environmental samples remains challenging. To facilitate high-throughput DNA quantification from environmental samples, we developed a novel DNA quantification method based on a non-linear curve-fitting approach to extract additional information from quantitative PCR amplification curves and used the fitted parameters to develop multiple regression standard equations for target DNA quantification. A 3-parameter sigmoidal function performed superior to a 4-parameter Weibull function for generating the multiple regression standard equations. In a verification experiment, target DNA was quantified in a series of ‘unknown’ samples in three soils using this approach and the results were compared to target DNA values determined using corrected and uncorrected Ct-based (threshold cycle) methods. For each method, the deviations from the expected target DNA content were determined. Results clearly showed that over all DNA concentrations, target DNA content determined by the non-linear curve-fitting method was more accurate and more precise than values predicted by all other methods. Analysis of variance conducted on the predicted DNA contents also revealed fewer statistical artifacts with the non-linear curve fitting method compared to the conventional Ct-based methods. The novel approach described here is accurate, inexpensive, and very amenable for automation and high-throughput applications.  相似文献   
95.
李相  丁建丽  黄帅  陈文倩  王娇  袁泽 《土壤》2016,48(5):1032-1041
基于典型研究区植被冠层实测高光谱数据和HSI高光谱影像数据,通过相关分析选择与不同深度土壤含水量响应敏感波段,建立两者的土壤含水量反演模型,并用实测高光谱土壤含水量反演模型校正HSI影像土壤含水量反演的模型。结果表明:土壤含水量响应敏感波段区域为450~650 nm和850~920 nm;两种土壤含水量反演模型对土壤深度为0~10 cm的土壤含水量估算效果最好,其中实测冠层高光谱土壤含水量反演模型精度高于HSI影像土壤含水量反演模型,判定系数(R~2)分别为0.659和0.557;经过校正的HSI影像土壤含水量反演模型精度有了较大的提高,判定系数(R~2)从0.557提升到0.719,均方根误差(RMSE)为0.043 5,较好地提高了区域尺度条件下土壤含水量监测精度,因此运用该方法进行土壤含水量遥感监测是可行的,为进一步提高区域尺度下土壤含水量定量遥感监测提供参考借鉴。  相似文献   
96.
Abstract –  We performed a tagging study on one of the spawning populations of northern pike ( Esox lucius L.) of the River Kajaaninjoki in Finland. Northern pike is the main predator in many lakes and rivers in the northern hemisphere. Previous tagging studies have shown a general tendency to sedentary behaviour by pike. Whether individuals in a fish population adapt a sedentary or moving strategy may affect population persistence. To study if the spawning population consists of sedentary or moving individuals and the pattern of movements, we tagged 40 pike with radio transmitters and followed them from May 2002 to June 2003. Pike were caught and tagged during the spawning season in the mouth of the River Kajaaninjoki which flows into one of the largest lakes in Finland, Lake Oulujärvi. Our results suggest that the pike spawning population consisted of sedentary pike ( N  = 16) dwelling the whole year in the river, and moving pike ( N  = 24) which moved to Lake Oulujärvi after the spawning period. Pike exhibited homing behaviour, as most of the migrating pike returned to the same spawning area in the following year. Large pike had a higher movement rate than small pike during the summer and seasonally the movement rate was lowest during the spring and highest during the summer.  相似文献   
97.
Abstract  The contraction of Tenualosa macrura (Bleeker) to the Sarawak coast and a small part of Sumatra, and the decline in its fishery mirror what has happened to three other species in the genus. Little was known of this species in its last stronghold in Sarawak where it is important for management and conservation reasons to understand its biology and life history. It forms part of a multispecies fishery where effort is uniform, but catches follow a lunar cycle. Tenualosa macrura is protandrous, but low numbers of small females suggest diandry. In Sumatra Tenualosa macrura spawn throughout the year, but in Sarawak have a seasonal peak in the NE monsoon (December). This has management implications because the Sarawak fishery ceases at this time because of adverse weather, hence reducing fishing pressure on spawning T. macrura . Management measures introduced in Sarawak for Tenualosa toli (Valenciennes) may therefore not be required for T. macrura .  相似文献   
98.
Because declines within amphibian populations can seldom be attributed to a single cause, it is important to focus on multiple stressors, both natural and anthropogenic. Variables such as UV-B radiation and chemical contamination can interact with one another in ways that might not be predicted from single-factor studies. We exposed southern leopard frog (Rana sphenocephala) tadpoles to the insecticide carbaryl and varying intensities of UV-B radiation in artificial ponds and examined their effects on survival, size at metamorphosis, and the duration of the larval period. Tadpole survival to metamorphosis was positively influenced by UV-B intensity. Tadpoles in ponds exposed to carbaryl contained over three times more algae and yielded larger metamorphs than control ponds. Although previous laboratory studies have indicated carbaryl becomes more toxic in the presence of UV-B, we did not find such an effect, perhaps because of the protection afforded by dissolved organic carbon within the ponds. Our research emphasizes the importance of conducting field studies to more accurately predict what occurs under a natural setting.  相似文献   
99.
AIM: To investigate the functions of GR in the course of hepatic secondary injury after severe multiple injury. METHODS: Rat model was produced by adopting severe thoracic impact injury accompanied with mono-side femur fracture, and glucocorticoid receptor was blocked before severe multiple injury. Hepatic macropathology and alterations under light microscope were examined. Maximal binding volume of glucocorticoid receptor (GR) in hepatic tissue was assayed by radio-ligand binding assay and protein content was assayed by Western blot. RESULTS: Maximal binding volume and protein content of GR were gradually decreased in hepatic tissue after severe multiple injury, obviously lower than that in normal control at 4 h after trauma (P<0. 01), and the lowest value was at 12 h after trauma. Maximal binding volume was 12. 9% of normal control (P<0. 01), and protein content was 21. 9% of normal control (P<0. 01). In addition, no significant pathological alteration in liver was found after trauma. However, the pathological analysis showed that the administration of GR blocker before severe multiple injury could cause severe hepatic congestion and infiltration of inflammatory cells in hepatic sinusoid in a dose-dependent manner. CONCLUSION: GR insufficiency could cause secondary hepatic injury in early stage after severe multiple injury, implying an important role of GR in injury and anti-injury mechanism of hepatic tissue cells.  相似文献   
100.
本文观察了1只38岁高龄的大熊猫多器官衰竭的病理学变化。病理剖检显示,该熊猫主要表现为实质器官充血、水肿和出血性变化;组织病理学检查发现,全身实质器官(除心、肺、脑外)均发生明显萎缩,胃、肠、肝、胰、肾等发生水肿变性或出血;此外,还观察到心肌纤维坏死后的瘢痕形成。结果表明,老龄大熊猫的多器官衰竭的病理学变化与其他动物相似;高龄大熊猫也易患心血管系统疾病,且具有较经的组织修复能力。  相似文献   
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