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41.
This study examined the effects of contact with wood on the living human body using a physiological index and subjective evaluation.
Consecutive blood pressure measurements were used as the physiological index, and sensory evaluation using the semantic differential
(SD) method was used for subjective evaluation. Consideration was also given to cases in which materials were cooled and heated
as well as kept at room temperature, to eliminate the effects of heat flux due to differences in thermal conductivity between
wood and other materials. It was found that contact with wood produced coarse/natural sensations, with no associated increase
in systolic blood pressure. Contact with cold wood created subjectively dangerous/uncomfortable but still coarse/natural sensations,
also with no associated increase in blood pressure; therefore, there was no correspondence between subjective evaluation and
physiological responses. Contact with aluminum kept at room temperature and cold acrylic plastic created flat/artificial and
dangerous/uncomfortable sensations, with an associated significant increase in blood pressure; thus, there was a close correlation
between subjective evaluation and physiological responses. It was therefore concluded that contact with wood, unlike artificial
materials such as aluminum, induces no physiological stress even when kept at room temperature or cooled.
Part of this report was presented at the 48th Annual Meeting of the Japan Wood Research Society in Shizuoka, April 1998 相似文献
42.
以睾丸总RNA为模板,运用RT-PCR方法扩增了SD大鼠和BALB/c小鼠的叠朊蛋白(PRND)基因,并将其克隆到pMD18-T载体中进行测序,运用生物信息学软件对这些序列进行了分析。结果表明获得的SD大鼠和BALB/c小鼠PRND基因的完整ORF片段,基因无内含子,分别编码178和179个氨基酸的前体蛋白。与GenBank登录的其他同品种鼠相应序列进行比较,SD大鼠发生了G187C点突变,相应地引起了G63R的氨基酸改变;BALB/c小鼠发生了G12T、C13G和C528T点突变,但只发生了L5V的氨基酸改变,其余均为同义置换。氨基酸一级结构分析显示2种PRND编码的Dopple蛋白均由氨基端的信号肽、中间的成熟蛋白和羧基端的GPI锚定结合区组成。二级结构预测表明,Dopple蛋白由3个α-螺旋和2个β-折叠片层组成。研究结果为进一步研究Dopple蛋白的结构、功能及其在传染性海绵状脑病发生发展中的作用提供了基础数据。 相似文献
43.
Construction of Chinese country parks has been developing quickly in recent years, but less effort has been made in the field of esthetic quantitative evaluation of landscape of the country parks. Based on the theories of landscape esthetics and psychology, this paper constructs a landscape quality evaluation model for the country parks by means of SBE and SD methods, with which the authors of the paper carried out the research on and evaluation of the landscape quality of four selected country parks outside the Fifth Ring Road in Beijing. The purpose of this paper is to further put forward suggestions for a better development of the landscape of the four country parks in order to bring their landscape and recreation functions into full play. The findings of this paper indicate that both natural and artificial landscape characteristics exercise either positive or negative influences on landscape quality; among them the effect of vitality, color richness, senses of both joy and beauty are the key elements affecting the attraction of the country park's landscape. Country parks boast with special significance because of their localism, naturalness and tranquility. These advantages are fully shown in their sufficient space for waterscape construction and conspicuous effect on landscape as reflected from the green belts previously constructed. Nevertheless, three major problems existed in the country parks including insipid color, over artificialized parkways, and peripheral high-rise buildings in the nearby neighborhood that have also given rise to visual interference. Recommendations for relevant landscape construction and protection of the country parks are suggested. 相似文献
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The assay was aimed to establish high fat diet induced metabolic syndrome (MS) model in male SD rat of nutrition.Four weeks old male SD rats were randomly divided into experimental group (n=24) and control group (n=6).The control group was fed with normal diet and the experimental group was fed with high fat diet which was composed of normal diet, egg yolk and peanuts.Two weeks later, the obesity resistant rats were excluded from the experimental group.Weight, systolic blood pressure and Lee's index were observed after thirty-two weeks.After twelve hours fasted, made the OGTT.Then all rats were sacrificed and tested for total cholesterol (TC) and serum triglyceride (TG).The experimental group weighted (794.0±63.5)g and the control group weighted (571.8±61.9)g, and the weights of rats of experimental group were 38.9% higher than that of control group.Lee's index of the experimental group was 343.0±8.7, while the control group was 319.2±7.1 (P<0.01).The levels of serum TC and TG of experimental group were extremely significantly higher than that of control group (P<0.01).Systolic blood pressure of the experimental group was 140.0±15.4, while the control group was 117.9±11.4, differences comparison of systolic blood pressure between experimental group and control group were significant (P<0.05).Insulin resistance of the experimental group was significantly (P<0.05).This study showed that four weeks old male SD rats were fed with high fat diet which was composed of normal diet, egg yolk and peanuts for thirty-two weeks could successfully and stably established metabolic syndrome model. 相似文献
48.
以不同浓度的玉米赤霉烯酮(Zearalenone,zEA)对大鼠睾丸间质细胞(Leydig)细胞进行染毒,采用噻唑蓝比色法观察了ZEA对Leydig细胞活力的影响;流式细胞术分析检测了ZEA对细胞的凋亡率、线粒体膜电位变化的影响;Westernblotting等技术检测了Bax、Bcl-2、caspase-3、caspase-9、PARP蛋白的表达情况。结果显示,ZEA可明显抑制睾丸Leydig细胞的活力(染毒各组与对照组比较P〈0.05),40mg/L染毒组相对活力为40.67%;与对照组比较,5、10、20mg/LZEA染毒组睾丸Leydig细胞凋亡率均极显著升高(P〈0.05),呈明显剂量关系;线粒体膜电位变化测定显示,各染毒组与对照组比,线粒体膜电位均下降(P〈0.05),且有明显的剂量关系;Westernblotting分析显示,与对照组比较,5、10、20mg/LZEA染毒组Bax、caspase-9、caspase-3、PARP蛋白表达均上调,bel-2蛋白表达均下调。结果表明,ZEA能诱导大鼠睾丸间质细胞发生凋亡,Bax、Bcl-2、caspase-9、caspase-3等基因参与ZEA诱导Leydig细胞凋亡的调控。 相似文献
49.
[目的]研究GABAergic神经元在VPM和"barrel"区的组织结构及形态特点;[方法]通过免疫组织化学的方法和激光共聚焦电子显微镜研究GABAergic神经元在VPM和"barrel"区分布状态;[结果]GABAergic神经元在VPM和"barrel"区分布状态不同,信息传递这2个区域编码程度也不一样;GABAergic在VPM区主要分布在列与列之间,且呈非对称分布,而GABAergic神经元的胞体、树突和轴突出现限定在"barrel"内,与周围"barrel"很少形成突触联系。[结论]提示VPM和"barrel"可能在信息传递及处理过程中具有不同的功能。 相似文献
50.