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81.
The Chinese crested ibis, Nipponia nippon, is a critically endangered bird. The current population of this species has developed from four wild individuals rediscovered in 1981. Given its conservation status, there is considerable interest in assessing the genetic diversity and individual relatedness in this species. For this purpose, a set of eight polymorphic di‐ or trinucleotide microsatellite loci was developed for the crested ibis. The expected heterozygosity at these loci ranges from 0.01 to 0.50, with less than four alleles being observed at individual loci, a reflection of the serious population bottleneck experienced by this species.  相似文献   
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83.
Multiple cellular events like dynamic actin reorganization and hydrogen peroxide (H2O2) production were demonstrated to be involved in abscisic acid (ABA)‐induced stomatal closure. However, the relationship between them as well as the underlying mechanisms remains poorly understood. Here, we showed that H2O2 generation is indispensable for ABA induction of actin reorganization in guard cells of Arabidopsis that requires the presence of ARP2/3 complex. H2O2‐induced stomatal closure was delayed in the mutants of arpc4 and arpc5, and the rate of actin reorganization was slowed down in arpc4 and arpc5 in response to H2O2, suggesting that ARP2/3‐mediated actin nucleation is required for H2O2‐induced actin cytoskeleton remodelling. Furthermore, the expression of H2O2 biosynthetic related gene AtrbohD and the accumulation of H2O2 was delayed in response to ABA in arpc4 and arpc5, demonstrating that misregulated actin dynamics affects H2O2 production upon ABA treatment. These results support a possible causal relation between the production of H2O2 and actin dynamics in ABA‐mediated guard cell signalling: ABA triggers H2O2 generation that causes the reorganization of the actin cytoskeleton partially mediated by ARP2/3 complex, and ARP2/3 complex‐mediated actin dynamics may feedback regulate H2O2 production.  相似文献   
84.
以抗倒伏品种‘南粳44’、‘武运粳7号’与不抗倒伏品系‘宁7412’为试验材料,通过对水稻不同生育期茎秆硅、钾、钙、镁含量及可溶性糖含量的测定,结合氮钾肥配比试验,研究了水稻不同生育期茎秆硅、钾、钙、镁含量及可溶性糖含量的变化及其与茎秆抗倒伏能力的关系。结果表明:水稻茎秆的硅、钙、镁含量及可溶性糖含量随生育进程呈上升趋势,而茎秆的钾含量呈现先降后升的趋势。在不同施肥水平条件下,水稻茎秆的硅、钾、钙、镁含量及可溶性糖含量存在一定的差异。抗倒伏品种‘南粳44’和‘武运粳7号’茎秆基部抗折力较强,施肥对水稻茎秆基部抗折力有一定的影响。水稻生殖生育期茎秆的硅含量、可溶性糖含量与茎秆基部抗折力呈极显著正相关(P〈0.01),与水稻抗倒伏能力的强弱有一定的关系。  相似文献   
85.
目的:探讨血清神经生长因子(Nerve Growth Factor,NGF)、脑源性神经营养因子(Brain Derived Neural Nutrition Factor, BDNF)、胶质纤维酸性蛋白(Glial Fibrillary Acidic Protein,GFAP)水平与老年血管性痴呆严重程度的相关性。方法:选择我院2016年1月至2018年12月收治的81例老年血管性痴呆患者,根据简易精神状态检查表(MMES)评分将其分为三组,以MMSE评分21~26分者为轻度组(26例),10~20分者为中度组(28例),0~9分者为重度组(27例),同时选择来院体检的50例健康者作为对照组,检测和比较各组的血清NGF、BDNF、GFAP水平,分析血清NGF、BDNF、GFAP水平与老年血管性痴呆患者MMSE分值的相关性。结果:老年血管性痴呆者的血清NGF、GFAP水平明显高于对照组(P0.05),血清BDNF水平明显低于对照组(P0.05)。轻度组、中度组、重度组的血清NGF、GFAP、BDNF水平对比差异均有统计学意义(P0.05):NGF水平:轻度组中度组重度组,BDNF水平:轻度组中度组重度组;GFAP水平:轻度组中度组重度组。血清NGF、BDNF水平与MMSE分值评分呈显著正相关(r_1=0.652,r_2=0.671,P0.05),血清GFAP水平与MMSE分值呈显著负相关(r3=-0.681,P0.05)。结论:血清NGF、BDNF、GFAP水平均与老年血管性痴呆的严重程度密切相关,可能用于评估老年血管性痴呆病情的严重程度。  相似文献   
86.
1. Natural selection favours females who can correctly assess the predation risk and hence avoid high‐risk oviposition sites and reduce the mortality rate of their offspring. In spite of the potential significance of such behaviour, relatively few studies have assessed the relationship between oviposition behaviour and predation risk. 2. The present study aimed to determine the sublethal effects of predators on oviposition site selection by gravid females, the foraging activity of larvae, and the life history traits of two mosquito species that breed in different habitats, Aedes albopictus Skuse (container breeder) and Culex tritaeniorhynchus Giles (wetland breeder). 3. Female C. tritaeniorhynchus avoided laying eggs at oviposition sites in the presence of a predator cue. In contrast, female A. albopictus laid eggs in both the absence and presence of the predator cue. 4. To examine the effects of predator cues on larval behaviour, experiments were conducted in the absence and presence of a predator cue. Although larval activity was lower in the presence of the predator cue than that in its absence in both species, C. tritaeniorhynchus responded to the predator cue more strongly than A. albopictus. Female A. albopictus that had been reared with caged predators exhibited an extended larval development period, whereas the adult C. tritaeniorhynchus reared in the presence of predators were smaller than those reared in their absence. 5. This finding might explain why C. tritaeniorhynchus avoid laying eggs in predator‐conditioned water, for example to increase the fitness of their offspring, but A. albopictus either cannot detect predator cues or are not sensitive to them.  相似文献   
87.
The Peruvian Andes presents a climate suitable for many species of sandfly that are known vectors of leishmaniasis or bartonellosis, including Lutzomyia peruensis (Diptera: Psychodidae), among others. In the present study, occurrences data for Lu. peruensis were compiled from several items in the scientific literature from Peru published between 1927 and 2015. Based on these data, ecological niche models were constructed to predict spatial distributions using three algorithms [Support vector machine (SVM), the Genetic Algorithm for Rule‐set Prediction (GARP) and Maximum Entropy (MaxEnt)]. In addition, the environmental requirements of Lu. peruensis and three niche characteristics were modelled in the context of future climate change scenarios: (a) potential changes in niche breadth; (b) shifts in the direction and magnitude of niche centroids, and (c) shifts in elevation range. The model identified areas that included environments suitable for Lu. peruensis in most regions of Peru (45.77%) and an average altitude of 3289 m a.s.l. Under climate change scenarios, a decrease in the distribution areas of Lu. peruensis was observed for all representative concentration pathways. However, the centroid of the species' ecological niche showed a northwest direction in all climate change scenarios. The information generated in this study may help health authorities responsible for the supervision of strategies to control leishmaniasis to coordinate, plan and implement appropriate strategies for each area of risk, taking into account the geographic distribution and potential dispersal of Lu. peruensis.  相似文献   
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