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151.
152.
《Bioscience, biotechnology, and biochemistry》2013,77(5):802-806
The effects were determined of dietary fish oil on the polyunsaturated fatty acid desaturation in rats fed on fish oil-containing diets (FS group) and on non-fish oil diets (CN group) during the fetal to postnatal periods. Although the desaturase activity in the liver microsomes of the FS group was higher than that of the CN group before birth, this was not altered by dietary fish oil after birth. However, a lower 20:4n-6 concentration before and after birth, and lower linoleic acid desaturation index ((dihomo-γ-linolenic acid + arachidonic acid)/linoleic acid)) at 10 wk of age in the FS group than in the CN group were observed in the liver microsomal phospholipids. The Δ6-desaturase activity in the brain microsomes of the FS group was lower than that of the CN group. These findings suggest that an intake of dietary fish oil by dams and postnatal rats affected the arachidonic acid concentration due to the decreased desaturase activity in the rats’ microsomes. 相似文献
153.
《Bioscience, biotechnology, and biochemistry》2013,77(9):1692-1697
Advanced glycation end product (AGE)-induced vascular smooth muscle cell (VSMC) proliferation is vital to the progression of diabetic vasculopathy. A grape seed procyanidin extract has been reported to possess anti-oxidative and anti-inflammatory properties and to display a significant cardiovascular protective effect, but little is know about the underlying mechanism. The objective of this present study was to determine whether GSPB2 (grape seed procyanidin B2), which is a dimeric procyanidin and more biologically active, could inhibit AGE-induced VSMC proliferation by affecting the production of ubiquitin COOH-terminal hydrolase 1 (UCH-L1), the degradation of IκB-α and nuclear translocation of NF-κB in human aortic smooth muscle cells (HASMCs). Our data show that GSPB2 preincubation markedly inhibited AGE-induced proliferation and migration of HASMCs in a dose-dependent manner and upregulated the protein level of UCH-L1. Further studies revealed that the GSPB2 pretreatment markedly attenuated the degradation of IκB-α and nuclear translocation of NF-κB by modulating ubiquitination of IκB-α in AGE-exposed HASMCs. These results collectively suggest that AGE-induced HASMC proliferation and migration was suppressed by GSPB2 through regulating UCH-L1 and ubiquitination of IκB-α. GSPB2 may therefore have therapeutic potential in preventing and treating vascular complications of diabetes mellitus. 相似文献
154.
Si-si Luan Fei Yu Bao-ying Li Rui-jie Qin Xiao-li Li Qian Cai 《Bioscience, biotechnology, and biochemistry》2013,77(9):1577-1583
Diabetic cardiomyopathy is one of the major complications of diabetes mellitus. Oxidative stress appears to play a substantial role in cardiomyopathy. Grape seed procyanidin B2 (GSPB2) has been known as an anti-oxidant in treating diabetes mellitus; however, little is known about its effects and underlying mechanisms on diabetic cardiomyopathy. The present study is to explore the molecular targets of GSPB2 responsible for the anti-oxidative effects in db/db mice by quantitative proteomics. GSPB2 (30?mg/kg body weight/day) were intragastric administrated to db/db mice for 10?weeks. Proteomics of the heart tissue extracts by isobaric tags for relative and absolute quantification analysis was obtained from db/db mice. Our study provides important evidence that GSPB2 protect against cardiomyopathy in diabetes mellitus, which are believed to result from regulating the expression of key proteins involving cardiac fibrosis and proliferation. GSPB2 could be expected to become novel clinical application in fighting against diabetic cardiomyopathy. 相似文献
155.
盐胁迫对山葡萄叶绿素荧光参数及超微结构的影响 总被引:3,自引:0,他引:3
采用不同浓度NaCl(0、0.1%、0.3%、0.5%)处理山葡萄品种‘左山二’幼苗,于盐胁迫20d时测定叶绿素荧光参数,盐胁迫25d时对0(CK)和0.3%NaCl溶液处理的植株进行叶片超微结构观察,以探讨山葡萄品种的耐盐机理。结果表明:(1)中度(0.3%)或重度(0.5%)盐胁迫下,山葡萄叶初始荧光(F0)显著升高,PSⅡ原初光化学效率(Fv/Fm)、PSⅡ潜在活性(Fv/F0)、光化学淬灭系数(qP)、实际光化学效率(ΦPSⅡ)、非光化学淬灭系数(NPQ)和电子传递效率(ETR)显著降低,表明叶片PSⅡ反应中心破坏,PSⅡ受体侧电子传递受害,通过热耗散散失过剩激发能的能力减弱。(2)中度盐胁迫条件下,叶绿体超显微结构较对照发生明显变化,其外形明显皱缩变短呈不规则球形,大的淀粉粒消失,质壁分离明显,基粒和基质片层界限模糊不清,被膜破损或解体,叶绿素内部质体小球增多,表明其形态结构已受到严重损伤。(3)盐胁迫处理下,山葡萄线粒体嵴排列紊乱,线粒体膜结构模糊不清或溶解,但未见明显的破裂现象,说明线粒体受害程度较叶绿体小,线粒体较叶绿体对NaCl相对不敏感。(4)盐处理下细胞核形态较对照发生改变,核膜溶解或消失,但未完全崩解,说明盐胁迫对细胞核造成了一定损伤。 相似文献
156.
贺兰山东麓酿酒葡萄的生态适应性 总被引:1,自引:0,他引:1
从抗寒性、光合特性、生长及其结果性状等方面研究了宁夏贺兰山东麓酿酒葡萄的生态适应性。室内抗寒性鉴定和田间抗寒评价结果表明:‘歌海娜’最不耐寒,抗寒性强的品种有‘长相思’、‘雷司令’、‘黑比诺’、‘佳美,;抗寒力较差的品种有‘赛美容’、‘白诗南’、‘白玉霓’、‘神索’;抗寒力较强的品种是:‘霞多丽’、‘赤霞珠,、‘梅鹿辄’、‘白比诺’、‘西拉’。对酿酒葡萄的光合特性的测定发现:同一立地不同品种的净光合速率(Pn)差异明显,‘赤霞珠’的光合速率远高于‘霞多丽’、‘梅鹿辄’的,各品种光合速率的日变化呈双“S”曲线;全天光合速率的最高峰出现在上午10:00左右,下午14:00出现光合低谷,次高峰出现在下午17:00左右。同一品种在不同立地上的叶面积(LA)、叶鲜重(LFW)、比叶重(SLW)、叶绿素(Ch1)含量均表现差异;不同品种在同一立地条件下以上几个指标也表现不同。酿酒葡萄在贺兰山东麓不同区域的生长结果表现也不同。研究表明:大多数酿酒葡萄品种在贺兰山东麓具有良好的生态适应性,土壤和品种是造成贺兰山东麓酿酒葡萄生态适应性差异的主要因素,该区酿酒葡萄栽培的首要任务是解决抗寒栽培技术和土壤培肥。 相似文献
157.
158.
‘峰早’和‘洛浦早生’葡萄分别是‘巨峰’和‘京亚’的早熟芽变,本研究对比分析了早熟芽变与其亲本间在果实发育过程中与成熟有关的生理指标动态变化的差异。结果表明,与亲本相比,两个早熟芽变品种在果实横径、纵径、单粒重的增长速率,叶绿素、类黄酮和总酚含量变化趋势,以及β-半乳糖苷酶活性等方面的变化趋势差别不大。可溶性固形物和可溶性糖的变化趋势、类胡萝卜素的含量及脂氧合酶(LOX)活性的变化趋势在两对芽变与亲本间无明显一致的趋势,表现出的情形比较复杂。但两芽变品种花色素苷的增长速率在花后50 d均显著快于亲本,且在成熟时的绝对含量均大于对应时期亲本,这可能是早熟芽变品种果实先着色的原因之一。两芽变与亲本间果胶甲酯酶(PE)活性和多聚半乳糖醛酸酶(PG)活性变化模式相一致,且两芽变的PG酶活性增长速率均明显大于其亲本,这种变化幅度也与早熟芽变性状变化的幅度相关,所以PG酶活性增加加快了芽变品种的成熟软化,这可能是芽变比亲本早熟的原因之一。 相似文献
159.
以刺葡萄幼胚为材料,研究不同培养方式、培养基配方和培养条件对其愈伤组织诱导的影响,采用正交试验设计法筛选刺葡萄愈伤组织继代增殖的培养基配方,并对继代保持的培养条件和方式进行优化,同时进行了高产原花青素刺葡萄愈伤组织细胞系的筛选研究。结果表明,刺葡萄幼胚以平放的方式接种到MS+1.0 mg·L^-1 2,4-D或MS+1.0 mg·L^-1 2,4-D+0.5mg·L^-1 KT的固体培养基上,在黑暗的条件下,能有效的诱导出愈伤组织,诱导效率为80%;刺葡萄愈伤组织继代增殖以MS+1.5 mg·L^-1 2,4-D或MS+1.5 mg·L^-1 2,4-D+0.5 mg·L^-1 KT的固体培养基为佳,并且采用此两种培养基交替继代培养,在光照条件下能长期保持旺盛且生长一致的刺葡萄愈伤组织;筛选出了紫红色松脆状的高产原花青素的刺葡萄愈伤组织细胞系,培养35 d后每克鲜样的原花青素含量可达1 671.16μg。 相似文献
160.
Andrew P. Gutierrez Luigi Ponti Monica L. Cooper Gianni Gilioli Johann Baumgärtner Carlo Duso 《Agricultural and Forest Entomology》2012,14(3):225-238
- 1 The polyphagous European grapevine moth Lobesia botrana (Den. & Schiff.) is the principal native pest of grape berries in the Palearctic region. It was found in Napa County, California, in 2009, and it has subsequently been recorded in an additional nine counties, despite an ongoing eradication programme. The present study aimed to assess prospectively its potential geographical distribution and relative abundance in California and the continental U.S.A. A subsidiary goal was to provide explanation for timing control measures.
- 2 Data from the European literature were used to formulate and parameterize a holistic physiologically‐based demographic model for L. botrana. This model was linked to an extant mechanistic model of grapevine phenology, growth and development that provides the bottom‐up effects of fruiting phenology, age and abundance on L. botrana dynamics. Fruit age affects larval developmental rates, and has carryover effects on pupal development and adult fecundity. Also included in the model were the effects of temperature on developmental, survival and fecundity rates.
- 3 Observed daily weather data were used to simulate the potential distribution of the moth in California, and the continental U.S.A. The relative total number of pupae per vine per year was used as the metric of favourability at all locations. The simulation data were mapped using grass gis ( http://grass.osgeo.org/ ).
- 4 The model predicts L. botrana can spread statewide with the highest populations expected in the hotter regions of southern California and the lower half of the Central Valley. In the U.S.A., areas of highest favourability include south Texas, and much of the southeast U.S.A.
- 5 The effects of a warmer climate on pest abundance were explored by increasing observed mean temperatures 2° and 3 °C. L. botrana abundance is expected to increase in northern California and in the agriculturally rich Central Valley but to decrease in the hot deserts of southern California where summer temperatures would approach its upper thermal limit.
- 6 Analysis of the timing of mating disruption pheromone for control of L. botrana suggests the greatest benefit would accrue by targeting adults emerging from winter diapause pupae and the flight of first summer adults.