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油松天然群体的种实性状表型多样性研究   总被引:1,自引:0,他引:1  
为了揭示油松天然种群在不同地理环境条件下表型变异的程度和规律,在油松整个天然分布范围内选择了12个具有代表性的居群作为研究对象,对其球果、种子、种翅等12个种实性状的变异程度及其与环境因子间关系进行了比较分析。结果显示:(1)各个性状在居群内和居群间均存在较大的变异(CV>12%)。其中千山(QS),曾家镇(ZJ)和互助(HZ)3个居群表现出了较高的变异(CV>20%),而球果干重(CDW)和种子长(CL)是所有表型性状中变异幅度最大的(CV分别为31%和21%),但种翅性状与其他性状相比具有较高的稳定性。(2)巢式设计方差分析表明,在居群内表型分化系数(Vst)变化在3.18%~89.86%之间,而群体间的Vst为38.97%;与其他针叶树种相比,油松拥有较高的表型分化系数,且居群内的变异程度远高于居群间的变异,尤其是千山(QS)、曾家镇(ZJ)和互助(HZ)3个居群,这说明油松具有较高的环境异质性适应能力或恶劣环境耐受能力。(3)相关性分析表明,该研究的各形态特征与潜在蒸发量均为负相关,且大部分形态指标间及它们与潜在蒸发量间存在显著相关性,表明潜在蒸发量是油松形态特征变化的最重要环境影响因子,预示油松最适宜生长于温暖潮湿的环境中;并表明因各形态特征间相互紧密关联,所以它们受环境条件影响而共变。  相似文献   
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Non-human primates (NHPs) are commonly infected with Cryptosporidium spp. and Giardia duodenalis. However, molecular characterisation of these pathogens from NHPs remains scarce. In this study, 2,660 specimens from 26 NHP species in China were examined and characterised by PCR amplification of 18S rRNA, 70 kDa heat shock protein (hsp70) and 60 kDa glycoprotein (gp60) gene loci for Cryptosporidium; and 1,386 of the specimens by ssrRNA, triosephosphate isomerase (tpi) and glutamate dehydrogenase (gdh) gene loci for Giardia. Cryptosporidium was detected in 0.7% (19/2660) specimens of four NHP species including rhesus macaques (0.7%), cynomolgus monkeys (1.0%), slow lorises (10.0%) and Francois’ leaf monkeys (6.7%), belonging to Cryptosporidium hominis (14/19) and Cryptosporidium muris (5/19). Two C. hominis gp60 subtypes, IbA12G3 and IiA17 were observed. Based on the tpi locus, G. duodenalis was identified in 2.2% (30/1,386) of specimens including 2.1% in rhesus macaques, 33.3% in Japanese macaques, 16.7% in Assam macaques, 0.7% in white-headed langurs, 1.6% in cynomolgus monkeys and 16.7% in olive baboons. Sequence analysis of the three targets indicated that all of the Giardia-positive specimens belonged to the zoonotic assemblage B. Highest sequence polymorphism was observed at the tpi locus, including 11 subtypes: three known and eight new ones. Phylogenetic analysis of the subtypes showed that most of them were close to the so-called subtype BIV. Intragenotypic variations at the gdh locus revealed six types of sequences (three known and three new), all of which belonged to so-called subtype BIV. Three specimens had co-infection with C. hominis (IbA12G3) and G. duodenalis (BIV). The presence of zoonotic genotypes and subtypes of Cryptosporidium spp. and G. duodenalis in NHPs suggests that these animals can potentially contribute to the transmission of human cryptosporidiosis and giardiasis.  相似文献   
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Doxorubicin, as a widely used chemotherapeutic, always causes multidrug resistance in human cancer cells. To circumvent drug resistance, we developed a novel formulation where doxorubicin hydrochloride (DOX) and chloroquine phosphate (CQ) were simultaneously loaded into liposomes by a pH-gradient method where CQ played the role of a chemical sensitizer. The various factors were investigated to optimize the formulation and manufacturing conditions of DOX and CQ coencapsulated liposomes (DCL). The resultant DCLs achieved the high encapsulation efficiency of both drugs over 90%. Further, DCLs significantly displayed resistance reversal action on a doxorubicin-resistant human breast cancer cell line (MCF-7/ADR) through the cooperation of CQ with DOX. The reversal fold of DCL with the DOX/CQ/soybean phosphatidylcholine weight ratio of 0.5:1:50 was 5.7, compared to free DOX. These results demonstrate that DCL is a promising formulation for the treatment of DOX-resistant breast cancer.  相似文献   
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We report herein the design and synthesis of a series of structural modified dimethylpyridazine compounds as novel hedgehog signaling pathway inhibitors. The bicyclic phthalazine core and 4-methylamino-piperidine moiety of Taladegib were replaced with dimethylpyridazine and different azacycle building blocks, respectively. The in vitro Gli-luciferase assay results demonstrate that the new scaffold still retained potent inhibitory potency. Piperidin-4-amine moiety was found to be the best linker between pharmacophores dimethylpyridazine and fluorine substituted benzoyl group. Furthermore, the optimization of 1-methyl-1H-pyrazol and 4-fluoro-2-(trifluoromethyl)benzamide by different aliphatic or aromatic rings were also investigated and the SAR were described. Several new derivatives were found to show potent Hh signaling inhibitory activity with nanomolar IC50 values. Among these compounds, compound 11c showed the highest inhibitory potency with an IC50 value of 2.33?nM, which was comparable to the lead compound Taladegib. In vivo efficacy of 11c in a ptch+/?p53?/? mouse medulloblastoma allograft model also indicated encouraging results.  相似文献   
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为了明确从3个马铃薯杂交组合F1代分离群体中选育出的7个马铃薯新品系(NMS-A42、NMS-A187、NMS-A217、NMS-B53、NMS-B107、NMS-B327和NMS-C92)的主要农艺性状、分子和细胞遗传学差异,并为进一步新品种的育成登记与推广提供依据。该试验以5个亲本材料为对照,对7个新品系块茎的单株产量、商品薯率、营养品质、熟性、花粉母细胞减数分裂中期Ⅰ(PMCMⅠ)染色体配对行为、花粉育性及SSR指纹特征等进行比较分析。结果表明:(1)NMS-A42的干物质和淀粉含量(24.15%和18.72%)显著高于其他6个品系,为全粉加工型新品系;NMS-B107为高花青素含量(319.49mg/kg)新品系;NMS-B327花青素含量(100.22mg/kg)较高,为彩薯新品系;其余4个新品系均为鲜食型。(2)NMS-B327为中早熟型品系,NMS-C92为晚熟型品系,其余5个新品系均为中熟型。(3)各品系平均单株产量和商品薯率变幅分别为1.02~1.84kg和81.10%~94.36%,且品系NMSB327均为最高;可育花粉率变幅为48.82%~87.69%,且以NMS-A42最低,NMS-B107最高。(4)7个新品系的染色体配对构型分别为:6.57Ⅰ+9.66Ⅱ+5.06Ⅲ+1.74Ⅳ、5.38Ⅰ+8.98Ⅱ+4.63Ⅲ+2.69Ⅳ、4.05Ⅰ+15.54Ⅱ+2.12Ⅲ+1.63Ⅳ、4.55Ⅰ+12.12Ⅱ+2.39Ⅲ+3.01Ⅳ、1.93Ⅰ+11.52Ⅱ+2.0Ⅲ+4.26Ⅳ、4.37Ⅰ+9.97Ⅱ+3.19Ⅲ+3.53Ⅳ和6.08Ⅰ+7.6Ⅱ+3.4Ⅲ+4.13Ⅳ。(5)从55对SSR引物中选出条带清晰、多态性丰富、重复性好的3对特异性引物(S25、S118和S153),PCR扩增建立了能清晰识别7个新品系和其亲本材料的SSR指纹图。研究发现,7个马铃薯优良新品系的块茎芽眼浅、薯形美观、结薯集中整齐,其熟性、产量、商品薯率和营养品质等性状表现各有特点,具有较高的应用价值。  相似文献   
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