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81.
Ryan D. Briscoe Runquist Eric Chu Justin L. Iverson Jason C. Kopp David A. Moeller 《Evolution; international journal of organic evolution》2014,68(10):2885-2900
A major goal of speciation research is to understand the processes involved in the earliest stages of the evolution of reproductive isolation (RI). One important challenge has been to identify systems where lineages have very recently diverged and opportunities for hybridization are present. We conducted a comprehensive examination of the components of RI across the life cycle of two subspecies of Clarkia xantiana, which diverged recently (ca. 65,000 bp). One subspecies is primarily outcrossing, but self‐compatible, whereas the other is primarily selfing. The subspecies co‐occur in a zone of sympatry but hybrids are rarely observed. Premating barriers resulted in nearly complete isolation in both subspecies with flowering time and pollinator preference (for the outcrosser over the selfer) as the strongest barriers. We found that the outcrosser had consistently more competitive pollen, facilitating hybridization in one direction, but no evidence for pollen–pistil interactions as an isolating barrier. Surprisingly, postzygotic isolation was detected at the stage of hybrid seed development, but in no subsequent life stages. This crossing barrier was asymmetric with crosses from the selfer to outcrosser most frequently failing. Collectively, the results provide evidence for rapid evolution of multiple premating and postzygotic barriers despite a very recent divergence time. 相似文献
82.
Washing is a standard step for enzyme‐linked immunosorbent assays (ELISA) performed on a paper‐based chip, in which nonspecific‐binding antibodies and antigens should be removed completely from the paper surface. In this study, a novel three‐dimensional (3D) washing strategy using a heating ring‐oven was carried out on a paper‐based chip. Compared with a plane washing mode by a ring‐oven, this 3D washing strategy obtained a lower background, as gravity played an important role in the washing step. The paper‐based chip was placed on a 3D plastic holder and the waste area was connected to a heating ring. Use of a heating waste area meant that the nonspecific‐binding protein was continuously carried to the waste area through gravity and capillary action. The angle between the plastic holder and the ring plane was carefully selected. The effect of washing on different parts of the detection area was investigated by upconversion fluorescence and chemiluminescence (CL). This novel 3D washing strategy was performed for carcinoembryonic antigen detection through CL and a lower detection limit of 2 pg ml?1 was obtained. This approach provides an effective washing strategy to remove nonspecific‐binding antibody from a paper‐based immunodevice. 相似文献
83.
Analysis of transcriptional and epigenetic changes in hybrid vigor of allopolyploid Brassica napus uncovers key roles for small RNAs 下载免费PDF全文
84.
85.
The feasibility of using genipin cross-linked type II collagen scaffold with rabbit bone marrow mesenchymal stem cells (RBMSCs)
to repair cartilage defect was herein studied. Induction of RBMSCs into chondrocytic phenotype on type II collagen scaffold
in vitro was conducted using TGF-β 3 containing medium. After 3-weeks of induction, chondrocytic behavior, including marker
genes expression and specific extracellular matrix (ECM) secretion, was observed. In the in vivo evaluation experiment, the
scaffolds containing RBMSCs without prior induction were autologous implanted into the articular cartilage defects made by
subchondral drilling. The repairing ability was evaluated. After 2 months, chondrocyte-like cells with lacuna structure and
corresponding ECM were found in the repaired sites without apparent inflammation. After 24 weeks, we could easily find cartilage
structure the same with normal cartilage in the repair site. In conclusion, it was shown that the scaffolds in combination
of in vivo conditions can induce RBMSCs into chondrocytes in repaired area and would be a possible method for articular cartilage
repair in clinic and cartilage tissue engineering. 相似文献
86.
镜鲤体长性状的QTL定位分析 总被引:1,自引:0,他引:1
以镜鲤良种后代为祖父母本所培育的杂交F2群体的68个个体为材料,利用553个分子标记(217个SSR和336个SNP标记)对其进行基因型检测,运用JoinMap4.0软件包对遗传连锁图谱进行构建。利用MapQTL5.0区间作图法(Interval mapping)进行QTL检测,通过置换实验(1 000次重复)确定连锁群显著性水平阈值。在对体长的区间定位中共检测到12个与体长性状相关的QTLs区间,分布在BL-1-1(SNP0137-SNP1481)、BL-4-1(SNP0092-HLJ797)、BL-5-1(SNP1268-HLJ423)、BL-7-1(HLJ870-SNP0702)、BL-12-1(SNP0922-HLJ639)、BL-16-1(HLJE351-SNP0674)、BL-25-1(SNP0394-SNP0862)、BL-35-1(HLJ668-SNP0832)、BL-43-1(SNP0389-SNP1425)、BL-47-1(HLJ057-HLJ1113)、BL-47-2(HLJ1439-HLJ1418)等11个连锁群上,解释表型变异范围是13.8%~64.9%,其中贡献率大于20%的主效QTLs有8个,是体长性状的主效QTLs区间。 相似文献
87.
KCNQ1 variants associate with hypertension in type 2 diabetes and affect smooth muscle contractility in vitro 下载免费PDF全文
Kuo‐Chin Huang Te‐Mao Li Xiang Liu Jin‐Hua Chen Wen‐Kuei Chien Yi‐Tzone Shiao Hsinyi Tsang Ting‐Hsu Lin Chiu‐Chu Liao Shao‐Mei Huang Ju‐Pi Li Cheng‐Wen Lin Jung‐Chun Lin Chih‐Chien Lin Chih‐Ho Lai Chi‐Fung Cheng Wen‐Miin Liang Chien‐Hui Hung Ching‐Chu Chen Ying‐Ju Lin Fuu‐Jen Tsai 《Journal of cellular physiology》2017,232(12):3309-3316
88.
A novel, sensitive electrochemical immunoassay has been developed based on the precipitation of silver on colloidal gold labels which, after silver metal dissolution in an acidic solution, was indirectly determined by anodic stripping voltammetry (ASV) at a glassy-carbon electrode. The method was evaluated for a noncompetitive heterogeneous immunoassay of an immunoglobulin G (IgG) as a model. The influence of relevant experimental variables, including the reaction time of antigen with antibody, the dilution ratio of the colloidal gold-labeled antibody and the parameters of the anodic stripping operation, upon the peak current was examined and optimized. The anodic stripping peak current depended linearly on the IgG concentration over the range of 1.66 ng ml(-1) to 27.25 microg ml(-1) in a logarithmic plot. A detection limit as low as 1 ng ml(-1) (i.e., 6 x 10(-12) M) human IgG was achieved, which is competitive with colorimetric enzyme linked immuno-sorbent assay (ELISA) or with immunoassays based on fluorescent europium chelate labels. The high performance of the method is attributed to the sensitive ASV determination of silver (I) at a glassy-carbon electrode (detection limit of 5 x 10(-9) M) and to the catalytic precipitation of a large number of silver on the colloidal gold-labeled antibody. 相似文献
89.
Mark Hamann Chu The Cuong Nguyen Duy Hong Pham Thuoc Bui Thi Thuhien 《Biodiversity and Conservation》2006,15(11):3703-3720
To establish baseline data on the distribution, abundance and threats to marine turtles in Viet Nam we conducted surveys with
local fishers, community members and provincial Ministry of Fisheries staff from 17 of Viet Nam’s 29 coastal provinces. These
data indicate that five species of marine turtle reside in Viet Nam’s waters (loggerhead, olive ridley, leatherback, green
and hawksbill turtles), and four species nest on Viet Nam’s beaches (all of the above except the loggerhead turtle). It is
evident from these data that significant declines have occurred in both foraging and nesting populations of all five marine
turtle species found in Viet Nam. The greatest current threats to marine turtle populations in Viet Nam are habitat degradation,
the accidental and opportunistic of turtles capture by fishers and the direct take of nesting females and their eggs. Successful
conservation efforts have been made in recent years through collaboration between international Non Government Organisations
and several Vietnamese Government Ministries. Continued success of these projects and the development and implementation of
marine conservation policy will depend upon building awareness among Government employees, fishers and the general public
about marine turtle biology, ecology, and the need to protect them. 相似文献
90.
Chu GH Gu M Cassel JA Belanger S Stabley GJ DeHaven RN Conway-James N Koblish M Little PJ DeHaven-Hudkins DL Dolle RE 《Bioorganic & medicinal chemistry letters》2006,16(3):645-648
A novel series of phenylamino acetamide derivatives was synthesized. These amides were shown to be potent and selective kappa opioid receptor agonists. 相似文献