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YIPENG DING HUAN NIU YIZHOU LI PING HE QUANNI LI YANHONG OUYANG MIN LI ZHIGAO HU YOUQING ZHONG PEI SUN TIANBO JIN 《Journal of genetics》2016,95(1):151-156
In this study, we examined and validated how common variants contribute to susceptibility to chronic obstructive pulmonary disease (COPD) in the Han Chinese population. Here, we genotyped 18 nucleotide polymorphisms and evaluated their association with COPD using chi-square test and genetic model analysis (246 COPD patients and 350 controls), and found three SNPs that might cause a predisposition to COPD. Both rs3025030 and rs3025033 are located on chromosome 6 in VEGF-A. We found one risk allele ‘C’ from rs3025030 and another ‘G’ from rs3025033 using the log-additive model (OR 1.40; 95% CI 1.05–5.96; P = 0.022), (OR 1.38; 95% CI 1.03–1.84; P = 0.03). We also found another risk allele ‘A’ of rs9296092 in gene region ZBTB9-BAK1 by the allele model (OR 2.63; 95% CI 1.27–5.45; P = 0.0078), (adjusted OR 3.53; 95% CI 1.12–11.11; P = 0.031). We found a risk haplotype ‘CG’ associated with the risk of COPD (OR 1.39; 95% CI 1.04–1.86; P=0.028). Our results when compared with previous studies showed significant association between VEGF-A polymorphism and COPD. We also identified rs9296092 as a risk factor for COPD. 相似文献
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STEFAN SAFER KARIN TREMETSBERGER YAN‐PING GUO GUDRUN KOHL MARY R. SAMUEL TOD F. STUESSY HERMANN STUPPNER 《Botanical journal of the Linnean Society. Linnean Society of London》2011,165(4):364-377
The genus Leontopodium comprises 30–41 species. The centre of diversity is the Sino‐Himalayan region in south‐western China, where about 15 species occur. The two species native to Europe, L. alpinum (known as the common ‘Edelweiss’) and L. nivale, are part of the cultural heritage of the people living there. Despite its importance, very little is known about the systematics of the genus. Because recent molecular studies have shown that species within this genus are closely related and difficult to distinguish with rDNA and cpDNA data, we used AFLPs to obtain a more detailed understanding of the phylogeny of the genus. Our main aims were as follows: (1) to clarify species relationships within the genus; and (2) to reveal information about the biogeography of the genus. We used AFLPs with six primer combinations to investigate 216 individuals in 38 populations of 16 different species. With AFLPs, we were able to recognize 10 different groups, all of which had strong bootstrap support. These results were also congruent with the morphology‐based taxonomy of the genus. Most private and rare fragments were found in the Yunnan region (south‐western China) relative to Europe and Mongolia/central China, suggesting a long‐lasting in situ history of populations in the centre of diversity of the genus. Our results illustrate the utility of AFLPs to resolve phylogenetic relationships between these closely related species. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 165 , 364–377. 相似文献
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The role of biofoam in shielding spittlebug nymphs (Insecta,Hemiptera, Cercopidae) against bright light 下载免费PDF全文
XU CHEN V. BENNO MEYER‐ROCHOW ALBERTO FERERES MARINA MORENTE AI‐PING LIANG 《Ecological Entomology》2018,43(3):273-281
1. Biofoam in spittlebugs has traditionally been seen as a defence against predation and a microclimate that reduces the risks of overheating and drying out. This study addresses the possible role of the foam as a light attenuator. 2. Nymphs exhibit higher mortalities when reared under brighter light (1800–2000 lux) than under less bright light (600–800 lux). At all developmental stages, photoavoidance is strongest when the nymphs are depleted of foam covers. First‐ and second‐instar nymphs appear to be the most vulnerable to exposures by bright light. 3. Smaller bubbles are more effective as light attenuators than are larger ones. As younger instars possess smaller canals from which bubbles are released and, furthermore, exhibit higher concentrations of proteins in bubble liquid, they can produce smaller‐sized bubbles and their foams are more effective at reducing light than are those of older nymphs. 4. The findings of this study show that most of the visible and UV radiation is reflected by the foam: transmittance of visible light was 15% at 600 nm and 12% at 350 nm. 5. These results demonstrate that spittlebug foam also possesses properties that render it an effective barrier against potentially damaging solar radiation. 相似文献
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粪便分解速率是粪便堆在自然条件下消失所用的时间,利用粪便距离取样法估算鹿科动物种群数量,是种群数量管理研究的重要基础。为揭示高纬度温带大陆性气候条件下的鹿科动物粪便分解速率,解决在我国普遍存在的目标种相对隐蔽、种群密度低、粪便分散导致的原地回访观测耗时耗力难以完成的问题,本研究在温带大陆性气候的小兴安岭范围内,选择铁力林业局建设林场为研究区,于2015年1月收集38堆马鹿(Cervus elaphus)的新鲜粪便,将这些粪便堆集中移至方便回访的一处马鹿代表性生境——阳坡针阔混交林,记录每堆粪便的原始粪粒数,之后间隔一定时间进行回访并记录每堆粪便剩余的粪粒数和各粪便堆是否分解完全,共回访8次。利用R 4.1. 2中的逻辑斯蒂回归得出回归方程的截距b0和斜率b1,再利用MATLAB R2020b计算粪便分解速率。结果表明,马鹿粪便的平均分解速率为(646±53) d。本研究将粪便人工移动集中放置于一处进行观测实验,为研究低种群密度的动物粪便分解速率提供了可行途径,丰富了我国鹿科动物粪便分解速率研究,从而减小了利用粪便距离取样法估算种群数量的阻碍。 相似文献
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目的:观察顺尔宁联合喘可治佐治小儿毛细支气管炎的临床疗效及其安全性。方法:选取2010年9月~2012年3月在我院儿科住院的70例毛细支气管炎患儿作为观察对象,按入院先后顺序随机分为治疗组和对照组,每组35例。两组均常规给予抗感染、解痉平喘、吸氧、镇静等综合治疗,治疗组在常规治疗的基础上加顺尔宁(孟鲁司特钠咀嚼片)口服,每天4 mg,每晚1次,以及喘可治注射液口服,每次半支,2次/日。治疗7天后观察和比较两组患儿的临床疗效,并对所有病例门诊随访3个月,观察各组患儿在此期间喘息再次发作的情况。结果:治疗7天后,治疗组的总有效率为97.1%,对照组的有效率为80.0%,两组间有显著性差异(X2=7.83,P〈0.05)。治疗组症状体征平均持续时间均较对照组明显缩短,差异有统计学意义(P〈0.05)。随访3个月内治疗组喘息反复发作的平均次数显著低于对照组,差异有统计学意义(P〈0.05)。两组均未见严重不良反应。结论:顺尔宁联合喘可治佐治毛细支气管炎临床疗效显著,并能缩短住院时间,由于顺尔宁可控制毛细支气管炎后的气道慢性炎症,喘可治注射液可增强呼吸道抵抗能力、减少呼吸道反复感染,对毛细支气管炎后喘息的反复发作有预防作用。 相似文献
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Abstract: Three‐dimensional fragments of palaeoscolecid cuticle have been recovered from the Furongian (upper Cambrian) of Hunan, South China. Extraordinary preservation of the fossils shows exquisite surface details indicating a three‐layered structure of the cuticle. One new genus and two new species Dispinoscolex decorus gen. et sp. nov. and Schistoscolex hunanensis sp. nov. are described. The co‐occurrence of these palaeoscolecid remains with those of Markuelia hunanensis allowed us to test the hypothesis that Markuelia, known hitherto only from embryonic remains, is an embryonic palaeoscolecid. The comparative anatomy of Markuelia and the co‐occurring palaeoscolecids shows a number of distinctions, particularly in the structure of the tail; all similarities are scalidophoran or introvertan (cycloneuralian) symplesiomorphies. The available evidence does not support the interpretation of Markuelia as an embryonic palaeoscolecid. 相似文献