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141.
目的 介绍一种从酵母、无绿藻及丝状真菌中提取DNA以用于PCR反应的方法。方法 所用菌种包括临床分离的未知菌株和保藏菌株共23株:未知酵母菌(5株)、真皮毛孢子菌(1株)、糠秕马拉色菌(1株)、季也蒙念珠菌(5株)、未知丝状真菌(6株)、无绿藻(1株)、烟曲霉(2株)、拟青霉菌(1株)、茎点霉(1株)。用溶细胞酶(lyticase)结合Biospin真菌基因组DNA提取试剂盒提取基因组DNA,A260/A280检测纯度并计算质量浓度,用真菌通用引物ITS1/ITS4扩增真菌核糖体基因(rDNA)内转录间区ITS基因,经PCR扩增检验所提取的DNA质量。结果 成功提取所有23株真菌基因组DNA,其纯度及质量浓度能满足PCR反应的要求。结论 用溶细胞酶结合Biospin真菌基因组DNA提取试剂盒从酵母菌、无绿藻及丝状真菌提取的DNA可用于PCR反应。  相似文献   
142.
目的研究屏障设施下裸小鼠繁殖生产时,在不同时间段剔除杂合仔鼠对纯合裸仔鼠的成活率及生长发育情况的影响。方法选取25窝头胎生BALB/c-nu新生裸小鼠按剔除杂合仔鼠的时间不同分成五组,以24h剔除组为对照比较纯合裸仔鼠生长发育及死亡率、离乳率的差异性,统计分析其生长发育过程中的体重增长等。结果剔除组生长发育及死亡率与对照组之间均存在差异性,其中14d剔除组和21d剔除组差异极显著。结论剔除杂合仔鼠的时间对纯合裸仔鼠的成活率及生长发育情况的有很大影响。为了保证SPF级裸鼠生长发育要求,生产繁殖出合格的实验用裸小鼠,剔除全部杂合仔鼠的最佳时间应该在新生仔鼠出生24h内,超过3d则会极大地影响纯合裸小鼠的正常生长发育。  相似文献   
143.
Allopatry is conventionally considered the geographical mode of speciation for continental island organisms. However, strictly allopatric speciation models that assume the lack of postdivergence gene flow seem oversimplified given the recurrence of land bridges during glacial periods since the late Pliocene. Here, to evaluate whether a continental island endemic, the Taiwan hwamei (Leucodioptron taewanus, Passeriformes Timaliidae) speciated in strict allopatry, we used weighted‐regression‐based approximate Bayesian computation (ABC) to analyse the genetic polymorphism of 18 neutral nuclear loci (total length: 8500 bp) in Taiwan hwamei and its continental sister species, the Chinese hwamei (L. canorum canorum). The nonallopatry model was found to fit better with observed genetic polymorphism of the two hwamei species (posterior possibility = 0.82). We also recovered unambiguous signals of nontrivial bidirectional postdivergence gene flow (Nem » 1) between Chinese hwamei and Taiwan hwamei until 0.5 Ma. Divergence time was estimated to be 3.5 to 2 million years earlier than that estimated from mitochondrial cytochrome b sequences. Finally, using the inferred nonallopatry model to simulate genetic variation at 24 nuclear genes examined showed that the adiponectin receptor 1 gene may be under divergent adaptation. Our findings imply that the role of geographical barrier may be less prominent for the speciation of continental island endemics, and suggest a shift in speciation studies from simply correlating geographical barrier and genetic divergence to examining factors that facilitate and maintain divergence, e.g. differential selection and sexual selection, especially in the face of interpopulation gene flow.  相似文献   
144.
以广州地区常见的200种(含变种、变型和品种)可食用植物为材料,对植物不同部位呈现的颜色以及不同季节色彩分布情况进行统计分析,总结可食用植物在色彩方面的特点及局限。其中,可食用植物叶、茎色以绿色为主,花、果色丰富。以色彩理论为基础,对可食用植物进行种植搭配实验,归纳相应的植物色彩搭配策略。策略包括三个方面,针对可食用植物叶色特点,提出绿色调可食用植物搭配策略;针对可食用植物色彩丰富度的差异,提出多部位色彩组合策略;针对植物时间维度的色彩分布差异及衔接空缺,提出持续的色彩植物搭配建议。  相似文献   
145.
目的:观察顺尔宁联合喘可治佐治小儿毛细支气管炎的临床疗效及其安全性。方法:选取2010年9月~2012年3月在我院儿科住院的70例毛细支气管炎患儿作为观察对象,按入院先后顺序随机分为治疗组和对照组,每组35例。两组均常规给予抗感染、解痉平喘、吸氧、镇静等综合治疗,治疗组在常规治疗的基础上加顺尔宁(孟鲁司特钠咀嚼片)口服,每天4 mg,每晚1次,以及喘可治注射液口服,每次半支,2次/日。治疗7天后观察和比较两组患儿的临床疗效,并对所有病例门诊随访3个月,观察各组患儿在此期间喘息再次发作的情况。结果:治疗7天后,治疗组的总有效率为97.1%,对照组的有效率为80.0%,两组间有显著性差异(X2=7.83,P〈0.05)。治疗组症状体征平均持续时间均较对照组明显缩短,差异有统计学意义(P〈0.05)。随访3个月内治疗组喘息反复发作的平均次数显著低于对照组,差异有统计学意义(P〈0.05)。两组均未见严重不良反应。结论:顺尔宁联合喘可治佐治毛细支气管炎临床疗效显著,并能缩短住院时间,由于顺尔宁可控制毛细支气管炎后的气道慢性炎症,喘可治注射液可增强呼吸道抵抗能力、减少呼吸道反复感染,对毛细支气管炎后喘息的反复发作有预防作用。  相似文献   
146.
The genus Leontopodium comprises 30–41 species. The centre of diversity is the Sino‐Himalayan region in south‐western China, where about 15 species occur. The two species native to Europe, L. alpinum (known as the common ‘Edelweiss’) and L. nivale, are part of the cultural heritage of the people living there. Despite its importance, very little is known about the systematics of the genus. Because recent molecular studies have shown that species within this genus are closely related and difficult to distinguish with rDNA and cpDNA data, we used AFLPs to obtain a more detailed understanding of the phylogeny of the genus. Our main aims were as follows: (1) to clarify species relationships within the genus; and (2) to reveal information about the biogeography of the genus. We used AFLPs with six primer combinations to investigate 216 individuals in 38 populations of 16 different species. With AFLPs, we were able to recognize 10 different groups, all of which had strong bootstrap support. These results were also congruent with the morphology‐based taxonomy of the genus. Most private and rare fragments were found in the Yunnan region (south‐western China) relative to Europe and Mongolia/central China, suggesting a long‐lasting in situ history of populations in the centre of diversity of the genus. Our results illustrate the utility of AFLPs to resolve phylogenetic relationships between these closely related species. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 165 , 364–377.  相似文献   
147.
One of the master regulators of adipogenesis and macrophage function is peroxisome proliferator-activated receptor-γ (PPARγ). Here, we report that a deficiency of β-arrestin-1 expression affects PPARγ-mediated expression of lipid metabolic genes and inflammatory genes. Further mechanistic studies revealed that β-arrestin-1 interacts with PPARγ. β-Arrestin-1 suppressed the formation of a complex between PPARγ and 9-cis-retinoic acid receptor-α through its direct interaction with PPARγ. The interaction of β-arrestin-1 with PPARγ repressed PPARγ/9-cis-retinoic acid receptor-α function but promoted PPARγ/nuclear receptor corepressor function in PPARγ-mediated adipogenesis and inflammatory gene expression. Consistent with these results, a deficiency of β-arrestin-1 binding to PPARγ abolished its suppression of PPARγ-dependent adipogenesis and inflammatory responses. These results indicate that the regulation of PPARγ by β-arrestin-1 is critical. Furthermore, in vivo expression of β-arrestin-1 (but not the binding-deficient mutant) significantly repressed adipogenesis, macrophage infiltration, and diet-induced obesity and improved glucose tolerance and systemic insulin sensitivity. Therefore, our findings not only reveal a molecular mechanism for the modulation of obesity by β-arrestin-1 but also suggest a potential tactical approach against obesity and its associated metabolic disorders.  相似文献   
148.
1. The importance of vertical mixing in modulating the impact of UVR on phytoplankton photosynthesis was assessed in a tropical, shallow lake in southern China from late winter to mid‐spring of 2005. 2. Daily cycles of fluorescence measurements (i.e. photosynthetic quantum yield, Y) were performed on both ‘static’ and in situ samples. Static samples were of surface water incubated at the surface of the lake under three radiation treatments – PAB (PAR + UVR, 280–700 nm), PA (PAR + UV‐A, 320–700 nm) and P (PAR, 400–700 nm). In situ samples were collected every hour at three different depths – 0, 0.5 and 1 m. 3. The general daily pattern was of a significant decrease in Y from early morning towards noon, with partial recovery in the afternoon. Samples incubated under static conditions always had lower Y than those under in situ conditions at the same time of the day. 4. Under stratified conditions, no overall impact of UVR impact could be detected in situ when compared with the static samples. Further rapid vertical mixing not only counteracted the impact of UVR but also stimulated photosynthetic efficiency. 5. Based on these measurements of fluorescence, the mixing speed of cells moving within the epilimnion was estimated to range between 0.53 and 6.5 cm min−1. 6. These data show that mixing is very important in modulating the photosynthetic response of phytoplankton exposed to natural radiation and, hence, strongly conditions the overall impact of UVR on aquatic ecosystems.  相似文献   
149.
利用抗病基因的保守结构设计引物,从抗叶锈病近等基因系材料TcLr24中扩增出一条703bp的条带RGAl,通过与GenBank比对,选取与RGAI高度同源的若干条带,在它们共有的保守序列位置设计引物,利用cDNA末端快速扩增(RACE):ffL术扩增抗病同源基因cDNA全长.扩增到3条全长cDNA,经BLASTp比较,这些序列都舍有NBS保守结构域和多个LRR结构域.与很多已知植物抗病基因的功能相应区域一致.对FRGA-1,、FRGA-2和FRGA-3实时定量PCR分析,表明这3个基因在小麦叶片中都是组成型表达.本研究在小麦材料TcLr24中得到3条抗病基因同源cDNA全长,为研究小麦抗病基因奠定了基础.  相似文献   
150.
目的:探讨RIP3(受体相互作用蛋白-3)在淋巴瘤患者病理组织中是否表达及其亚细胞定位,并初步观察RIP3的表达是否与淋巴瘤病理恶性度相关。方法:(1)利用免疫组化技术检测48例淋巴瘤和非肿瘤侵润淋巴结病理组织中RIP3表达,并观察RIP3亚细胞定位。结果:(1)RIP3在淋巴瘤患者病理组织中均有表达,其亚细胞定位主要在细胞核,在细胞质中相对弱表达。(2)RIP3表达与淋巴瘤病理恶性度可能存在相关性。结论:RIP3在淋巴瘤患者病理组织中存在阳性表达,为研究RIP3是否与淋巴瘤的发病、临床表现和预后相关,提供了新的探索途径。  相似文献   
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