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991.
中药注射剂澄明度影响因素的研究进展 总被引:1,自引:0,他引:1
本文介绍了中药注射剂在生产过程中影响澄明度的因素。在分析过程中以生产流程为主线,介绍了各个生产环节对澄明度的影响,重点分析了原料药材、pH值、安瓿、灌装、封口的影响因素及提高澄明度的有效措施。 相似文献
992.
背景与目的:中药中的砷含量及其形态学研究已成为当前中医药领域的研究热点。本文旨在建立科学和可行的砷含量检测方法,并对部分中药中的砷含量进行了测定。方法:中药材样品湿法消化后,采用原子荧光光谱法检测其中的砷含量,并对消化液的种类以及干扰的消除进行了探讨。结果:本法检出限为0.05μg·L~(-1),样品加标回收率在96.6%~101.6%范围内,相对标准偏差小于2.36%。检测结果显示,大部分中药材中均含有一定量的砷,部分中药材中砷舍量较高。结论:本法灵敏度高,操作简便,重现性好,能够应用于中药材中不同含量砷的分析,具有一定的实用价值。 相似文献
993.
补血中药在我国中医药宝库中占有十分重要的地位,中药调控造血的分子机制与细胞因子网络直接相关。多维超高通量药物筛选体系的建立和从分子水平系统说明中药作用的药理学机制,使传统的中药理论与国际通用的医学理论模式接轨,是中药现代化、国际化的迫切要求。由于中药重整体、多靶点、多环节的作用方式,使得传统的研究技术难以完整地阐明其作用机制;而现今发展起来的高密度基因芯片技术,可以同时研究上千种基因的作用模式,进行平行基因分析,因此可以用来检测疾病状态下和中药作用后成千上万个基因的表达模式,并对其进行定性和定量分析,从而使从整体和分子水平上阐明中药作用机制成为可能。基因芯片这种高通量、快速、平行的基因信息处理和分析技术,是实现这一目标的绝佳实验手段。在药物领域对于药物靶标的发现、多靶位同步超高通量药物筛选、药物作用的分子机理、中医药基础理论现代化、药物活性及毒性评价等都有其他方法无可比拟的优越性。因此,建立以基因芯片技术为核心的多靶点、多层次、多水平的中药多维超高通量筛选体系具有极其重要的意义。 相似文献
994.
Lin ZH Qu YF Ji X 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2006,143(4):508-513
Caudal autotomy is a defense mechanism used by numerous lizards to evade predators, but this entails costs. We collected 294 adult Chinese skinks (Eumeces chinensis) from a population in Lishui (eastern China) to evaluate energetic and locomotor costs of tail loss. Of the 294 skinks, 214 (c. 73%) had previously experienced caudal autotomy. Neither the proportion of individuals with regenerated tails nor the frequency distribution of locations of the tail break differed between sexes. We successively removed four tail segments from each of the 20 experimental skinks (adult males) initially having intact tails. Lipid content in each removed tail segment was measured, and locomotor performance (sprint speed, the maximal length traveled without stopping and the number of stops in the racetrack) was measured for each skink before and after each tail-removing treatment. Another independent sample of 20 adult males with intact tails was measured for locomotor performance to serve as controls for successive measurements taken for the experimental lizards. Caudal lipids were disproportionately stored along the length of the tail, with most lipids being aggregated in its proximal portion. Tail loss significantly affected sprint speed, but not the maximal length of, or the number of stops during the sprint. However, the adverse influence of tail loss on sprint speed was not significant until more than 51% of the tail (in length) was lost. Our data show that partial tail loss due to predatory encounters or other factors may not severely affect energy stores or locomotor performance in E. chinensis. As tail breaks occurred more frequently in the proximal portion of the tail in skinks collected from the field, we conclude that caudal autotomy occurring in nature often incurs substantial energetic and locomotor costs in E. chinensis. 相似文献
995.
对中药学专业微生物学课程教学内容及模式进行优化改革,以期提升课程的教学质量,进一步激发学生的学习兴趣,夯实基础知识和专业技能。首先分析了目前中药学专业开设的微生物学课程中出现的实际问题,其次在总课时不变的前提下,基于中药材及其相关微生物,并结合地方及中医药特色,进行教学内容的调整、教学手段的改革和考核方式的完善等,使该门课程更符合专业发展需求。在理论教学中调整课时比例,突出微生物学基础知识及微生物在药学中的应用两部分内容。在实践教学中进行分层教学,加深学生对课程知识的理解,同时突出目标导向,培养学生综合实践能力。在教学手段方面,采用模块化与其他教学模式相结合的方式,帮助学生构建微生物学相关知识体系,理解并掌握所学知识。此外,增加平时学习情况及实践方面的考核比例,促使学生重视课程学习及实践能力培养。课程优化后,学生的学习难度有所下降,学习目标更加明确,所学的微生物学知识与中药学专业联系更为密切,更加符合人才培养目标。 相似文献
996.
野生大鲵繁殖洞穴生态环境的初步研究 总被引:7,自引:0,他引:7
为了探明野生大鲵(Andrias davidianus)自然繁殖所需要的主要生态条件,给人工养殖条件下大鲵的自然繁殖提供生态学依据,对张家界国家级大鲵保护区境内野生大鲵的栖息繁殖洞穴进行生态学考察。对海拔、洞口的宽度与高度等10个生态因子进行定量观测和主成分分析,结果表明,影响大鲵选择繁殖洞穴的主要因子是海拔、洞口高度、洞底组成,以及洞穴中水的透明度、pH、流速、饵料丰度7个因子。对大鲵繁殖洞穴相连河段进行调查,发现多为山溪流。对繁殖洞穴中水的溶解氧、化学耗氧量、硫化物等5项主要指标进行检测,除硫化物外,其他指标多达到国家饮用水的水质标准,可见大鲵自然繁殖对洞穴与水质的要求较高。 相似文献
997.
998.
Medicinal plants and their endophytes are important resources for discovery of natural products. Several previous studies
have found a positive correlation between total antioxidant capacity (TAC) and total phenolic content (TPC) of many medicinal
plant extracts. However, no information is available on whether such a relationship also exists in their endophytic fungal
metabolites. We investigated the relationship between TAC and TPC for 292 morphologically distinct endophytic fungi isolated
from 29 traditional Chinese medicinal plants. The antioxidant capacities of the endophytic fungal cultures were significantly
correlated with their total phenolic contents, suggesting that phenolics were also the major antioxidant constituents of the
endophytes. Some of the endophytes were found to produce metabolites possessing strong antioxidant activities. Several bioactive
constituents from the fungal cultures and host plant extracts were identified. This investigation reveals that the metabolites
produced by a wide diversity of endophytic fungi in culture can be a potential source of novel natural antioxidants. 相似文献
999.
Zhao L Young WY Li R Wang Q Qian Y Guan MX 《Biochemical and biophysical research communications》2004,325(4):1503-1508
Mutations in mitochondrial DNA (mtDNA), particularly those in the 12S rRNA gene, have been shown to be associated with sensorineural hearing loss. Here we report the clinical and sequence analysis of the entire mitochondrial genome in three Chinese subjects with aminoglycoside-induced and non-syndromic hearing impairment. Clinical evaluation showed a variable phenotype of hearing impairment including the age of onset and audiometric configuration in these subjects. Sequence analysis of the complete mitochondrial genomes in three subjects showed the distinct sets of mtDNA polymorphism, in addition to the identical mitochondrial 12S rRNA T1095C mutation. This mutation was previously identified to be associated with hearing impairment in three families from different genetic backgrounds. The T1095C mutation was absent in 364 Chinese control. In fact, the occurrence of the T1095C mutation in these several genetically unrelated subjects affected by hearing impairment strongly indicates that this mutation is involved in the pathogenesis of hearing impairment. Among other nucleotide changes, the A2238G and T2885C mutations in the 16S rRNA, the I175V mutation in the CO2, the F16L mutation in the A6 and the V112M mutation in the ND6 exhibited a high evolutionary conservation. These data suggest that the T1095C mutation may be associated with aminoglycoside-induced and non-syndromic hearing impairments and A2238G and T2885C mutations in the 16S rRNA, the I175V mutation in the CO2, the F16L mutation in the A6 and the V112M mutation in the ND6 may contribute to the phenotypic expression of the T1095C mutation in these subjects. 相似文献
1000.
The influence of the peptide-to-cell ratio and energy depletion on uptake and degradation of the cell-penetrating peptides (CPPs) MAP (model amphipathic peptide) was investigated. The intracellular concentration of the CPPs, MAP and penetratin was monitored while varying the number of cells at fixed peptide concentration and incubation volume, or changing the concentration and incubation volume at fixed cell number. The uptake of CPPs was shown to be dependent on the peptide/cell ratio. At given peptide concentration and incubation volume, the intracellular concentration of peptide increased with lower cell number. At given cell number, doubling of the incubation volume increased intracellular peptide concentration to a similar extent as the doubling in incubation concentration. From a practical view, this means that the peptide/cell ratio has at least the same importance for the uptake of CPPs as the used peptide concentration. No influence of the peptide/cell ratio was found for the cellular uptake of peptide nucleic acid (PNA), or a non-amphipathic MAP analogue, investigated in parallel for comparison purposes.Energy depletion resulted in significantly reduced quantities of intracellular fluorescence label. Moreover, we show that this difference is mainly due to a membrane-impermeable fluorescent-labelled degradation product, which is lacking in energy-depleted cells. The mechanism of its generation is not likely to be endosomal degradation of endocytosed material, as it is not chloroquine- or brefeldin-sensitive. 相似文献