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51.
52.
B. Naser B. Lund H.-H. Henneicke-von Zepelin G. Khler W. Lehmacher F. Scaglione 《Phytomedicine》2005,12(10):715-722
The aim of this study was to verify the efficacy and safety of an herbal medication containing an extract of a mixture of Baptisiae tinctoriae radix, Echinaceae pallidae/purpureae radix and Thujae occidentalis herba (SB-TOX) in the treatment of upper respiratory tract infections (URIs), and to test whether SB-TOX's clinical efficacy is dose dependent. A total of 91 adults (mean age 42.1±13.0 years) were randomised to receive 19.2 mg of SB-TOX (n=31), 9.6 mg SB-TOX (n=29) or placebo (n=31) three times daily for 3–12 days. Since a “running nose” is the main symptom of a common cold, the total number of facial tissues used throughout the clinical duration of their cold was the primary efficacy parameter. In the intention-to-treat analysis, this total number of tissues decreased with increasing extract dose. The slope across groups according to the Jonckheere test was significant (p=0.0259). In the high-dose group, the standardised effect size Δ/SD was 0.46 compared with placebo. Time to relevant improvement in cold symptoms (measured as the time until less than 30 tissues per day were used) was 1.1 days (95% CI 0.52; 1.67), 0.76 days (95% CI 0.28; 1.24) and 0.52 days (95% CI 0.22; 0.82) in the placebo, low-dose and high-dose groups, respectively (pLogRank=0.0175). No adverse events were reported. This study demonstrates the efficacy and safety of SB-TOX in the treatment of URIs, and that its efficacy is dose dependent. 相似文献
53.
长江源区紫花针茅高寒草原优势植物化学元素含量特征 总被引:1,自引:0,他引:1
分析了长江源区紫花针茅草原的土壤和17种优势植物中15种元素的自然含量特征。植物中>1 000μg.g~(-1)的元素有Ca和Na,100~1 000μg.g~(-1)的元素有K、Mg、Mn、Fe、Li和Sr,10~100μg.g~(-1)的元素有Zn、Cu和Cr,<10μg.g~(-1)的元素有Ni、Co、Pb和Cd。土壤中各元素含量的顺序为Ca>Fe>Mn>Mg>K>Li>Na>Sr>Cr>Zn>Cu>Ni>Co>Cd>Pb。植物和土壤中元素含量特点是Ca>K型。植物对于土壤元素的吸收能力大小顺序是:Na>Sr>K>Zn>Mg>Ni>Pb>Cu>Mn>Ca>Li>Co>Cd>Fe>Cr,植物对于Na吸收系数达到13.228,其富集能力明显大于其余14种元素。元素之间K的累积与其他元素没有显著的相关关系;Na的累计也仅与Zn、Sr呈显著相关与其他元素无显著的相关关系,Pb和Na呈显著负相关。 相似文献
54.
Natural hybridization is very common in plants, and plays an important role in plant evolution. Besides the traditional methods including morphological analysis and hand crossing, molecular evidence is needed for studying natural hybridization.In order to analyze natural hybridization in Roscoea,HAT-RAPD technique was used toidentify putative hybrids from parental species by principal co ordinate analysis and hybrid index. The results indicated that the bands amplified by HAT-RAPD technique were more stable and reliable than that of RAPD. The result of principal co ordinate analysis and hybrid index showed that intermediate individuals were the hybrids of R.humeana and R.cautleoides, and showed closer relationships to R.humeana. These results suggested that HAT-RAPD could be used to study natural hybridization. As it is simple and easy to manipulate, HAT RAPD may prove to be a very effective technique in hybrid identification in the studies of plant evolution. 相似文献
55.
利用LI-6400便携式光合作用测定仪, 测定不同灌溉措施下紫花针茅(Stipa purpurea)的光合特性对CO2浓度和温度的响应, 探讨了土壤水分、温度和CO2浓度升高对藏北高寒草地紫花针茅光合作用的影响。结果表明: 1)紫花针茅各项光合特性参数对CO2浓度、温度和土壤水分的变化响应显著, 并表现出明显的交互作用; 2) CO2浓度升高促进光合速率, 但CO2浓度过高时光合速率反而下降; 温度升高抑制光合速率, 土壤水分增加对高温条件下的光合作用具有补偿作用; 土壤水分增加促进紫花针茅光合速率的升高; 3)随着CO2浓度的升高, 胞间CO2浓度逐渐增大, 蒸腾速率降低, 水分利用效率升高, 气孔导度逐渐减小, 且温度升高加剧气孔导度下降的程度。各光合参数在不同温度水平和土壤水分下表现不同: 气孔导度在20 ℃时达到最大值, 且土壤水分增加利于气孔导度的增大; 温度上升抑制了胞间CO2浓度, 且在土壤水分充足的条件下更显著; 蒸腾速率随着温度的上升而加快, 蒸腾速率与土壤水分的正相关关系明显; 叶片饱和水汽压亏缺与温度成正比, 充足的土壤水分会适当降低饱和水汽压亏缺; 水分利用效率随着温度上升和土壤水分增多而减小。不同土壤水分条件下光合参数对温度的响应结果表明, 土壤水分的增加对较高温度下光合及其生理参数与温度的关系具有一定的补偿作用。 相似文献
56.
青海麦秀林场紫果云杉次生林的干扰重建 总被引:2,自引:0,他引:2
对青海麦秀林场2个50m×50m紫果云杉(PiceapurpureaMast.)样方调查和604株树木年轮系统及157个树桩的分析结果表明:2个样方的干扰强度总体都较高,如PⅠ样方1950′s达到31.4% 10a,PⅡ样方1980′s达到18.1% 10a,说明存在经常性的择伐或盗伐活动,设定近30a来实际发生的干扰强度用树桩断面积与树桩和树木断面积的百分率来表示,并与用树轮分析的干扰重建百分比相比较,结果发现具有正态树龄分布的PⅠ样方的重建值与实际值较为接近,而不具有正态树龄结构分布的PⅡ样方,其重建值明显高于实际值。 相似文献
57.
Colonisation of pitcher plant leaves at several spatial scales 总被引:1,自引:0,他引:1
Abstract. 1. The effect of meso-scale (zone within bog and local plant density) and fine-scale (leaf length and resource availability) factors on the colonisation of pitcher plant leaves by arthropods was examined in an eastern Canadian bog.
2. In spring, the abundances of three arthropods, the mosquito Wyeomyia smithii , the midge Metriocnemus knabi , and the mite Sarraceniopus gibsoni , were determined for plots with low, moderate, and high densities of pitcher plants. All overwintering inhabitants were then removed from the plots. Newly opening leaves were colonised from outside the plots, and arthropod abundances were assessed again in autumn.
3. Pitcher plant fauna varied in their response to the meso-scale factors. In autumn (soon after colonisation), midges were more abundant in areas with high densities of pitcher plants. The relationship between mosquito abundance and plant density, and the variation in abundance among zones within the bog in the spring, were probably due to overwintering mortality.
4. All taxa responded to the fine-scale factors, leaf length, and capture rate, in the autumn, but the strength of the responses frequently depended on a meso-scale factor (plant density), in which responses were usually strongest where plants were sparse. Thus, the interaction between meso- and fine-scale processes needs to be considered when interpreting patterns of species abundance within arthropod assemblages in pitcher plant leaves. 相似文献
2. In spring, the abundances of three arthropods, the mosquito Wyeomyia smithii , the midge Metriocnemus knabi , and the mite Sarraceniopus gibsoni , were determined for plots with low, moderate, and high densities of pitcher plants. All overwintering inhabitants were then removed from the plots. Newly opening leaves were colonised from outside the plots, and arthropod abundances were assessed again in autumn.
3. Pitcher plant fauna varied in their response to the meso-scale factors. In autumn (soon after colonisation), midges were more abundant in areas with high densities of pitcher plants. The relationship between mosquito abundance and plant density, and the variation in abundance among zones within the bog in the spring, were probably due to overwintering mortality.
4. All taxa responded to the fine-scale factors, leaf length, and capture rate, in the autumn, but the strength of the responses frequently depended on a meso-scale factor (plant density), in which responses were usually strongest where plants were sparse. Thus, the interaction between meso- and fine-scale processes needs to be considered when interpreting patterns of species abundance within arthropod assemblages in pitcher plant leaves. 相似文献
58.
In this paper, the volatile oil of 18 samples from Cyathod/ne purpurea were determined by seam distilling method. 27 constituents of volatih oil were identitied qualitativdy and quantitativdy by GC/MS. Three samples of volatih oll have been tested for cytotoxicity in cell growth inhibition against cultured L1210 murine leukemia cell. 相似文献
59.
This paper deals with the haustorium development of parasitic plant (Cassytha filiformis L.) parasitized on purple willow (Salix purpurea L.).The polarity occurred in the portion near the host; and the cushion-shaped haustorial plate formed, and then the haustorial primordium initiated in the cortex. Finally, the haustoria reached the cortex of pith of the host, penetrating through its own cortex and epidermis. Tracheary elements were differentiated from the base of the haustoria and the sieve elements were not observed in the haustoria. Histochemical studies revealed that there were starch grains in normal stem cortex. The starch grains were increased in the portion near the axis after twisting on host. After the haustorial plate was formed, the starch grains were richly accumulated in the central group of cells, which were followed by the haustorial development; The starch disappeared in the meristem, in which protein stained deeply; The dynamic change of protein turned oK to be contrary to the tendency of starch accumulation. The structure and parasitic mechanism and the dynamic change of starch and protein are discussed. 相似文献
60.
本文对四川松潘地区海拔3200—3300m的紫果云杉(Picea purpurea)天然中龄林分生物量和生产力进行了测定和研究。按平均标准木法和样方收获法分别调查了乔木层、幼树下木层、草本地被物层和枯枝落叶层的生物量。据调查数据,建立了估测乔木层单株林木各器官生物量的回归方程,方程的相关系数和估测的精度都较高,具有实用价值。结果表明:林分总生物量平均为158.779吨/公顷,净生产量为3.259吨/公顷·年。其中乔木层生物量为134.408吨/ 公顷,净生产量为2.890吨/公顷·年。研究证实叶面积指数与林分乔木层的生产力关系十分紧密。在—定范围内,叶面积指数为4.34的林分比叶面积指数3.32的,其乔木层净生产量可增加47.2%。林冠浓密的林分比林冠稀疏的生产力要高。另外,林分的产量结构上反映出下层木结 构不合理,应予间伐。 相似文献