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31.
K. R. Duffield J. Hunt J. Rapkin B. M. Sadd S. K. Sakaluk 《Journal of evolutionary biology》2015,28(10):1872-1881
Investment in current versus future reproduction represents a prominent trade‐off in life‐history theory and is likely dependent on an individual's life expectancy. The terminal investment hypothesis posits that a reduction in residual reproductive value (i.e. potential for future offspring) will result in increased investment in current reproduction. We tested the hypothesis that male decorated crickets (Gryllodes sigillatus), when cued to their impending mortality, should increase their reproductive effort by altering the composition of their nuptial food gifts (i.e. spermatophylaxes) to increase their gustatory appeal to females. Using a repeated‐measures design, we analysed the amino acid composition of spermatophylaxes derived from males both before and after injection of either a saline control or a solution of heat‐killed bacteria. The latter, although nonpathogenic, represents an immune challenge that may signal an impending survival threat. One principal component explaining amino acid variation in spermatophylaxes, characterized by a high loading to histidine, was significantly lower in immune‐challenged versus control males. The relevance of this difference for the gustatory appeal of gifts to females was assessed by mapping spermatophylax composition onto a fitness surface derived in an earlier study identifying the amino acid composition of spermatophylaxes preferred by females. We found that immune‐challenged males maintained the level of attractiveness of their gifts post‐treatment, whereas control males produced significantly less attractive gifts post‐injection. These results are consistent with the hypothesis that cues of a survival‐threatening infection stimulate terminal investment in male decorated crickets with respect to the gustatory appeal of their nuptial food gifts. 相似文献
32.
ITMSQ: A software tool for N‐ and C‐terminal fragment ion pairs based isobaric tandem mass spectrometry quantification 下载免费PDF全文
Li‐Qi Xie Lei Zhang Ai‐Ying Nie Guo‐Quan Yan Jun Yao Yang Zhang Peng‐Yuan Yang Hao‐Jie Lu 《Proteomics》2015,15(22):3755-3764
Tandem MS (MS2) quantification using the series of N‐ and C‐terminal fragment ion pairs generated from isobaric‐labelled peptides was recently considered an accurate strategy in quantitative proteomics. However, the presence of multiplexed terminal fragment ion in MS2 spectra may reduce the efficiency of peptide identification, resulting in lower identification scores or even incorrect assignments. To address this issue, we developed a quantitative software tool, denoted isobaric tandem MS quantification (ITMSQ), to improve N‐ and C‐terminal fragment ion pairs based isobaric MS2 quantification. A spectrum splitting module was designed to separate the MS2 spectra from different samples, increasing the accuracy of both identification and quantification. ITMSQ offers a convenient interface through which parameters can be changed along with the labelling method, and the result files and all of the intermediate files can be exported. We performed an analysis of in vivo terminal amino acid labelling labelled HeLa samples and found that the numbers of quantified proteins and peptides increased by 13.64 and 27.52% after spectrum splitting, respectively. In conclusion, ITMSQ provides an accurate and reliable quantitative solutionfor N‐ and C‐terminal fragment ion pairs based isobaric MS2 quantitative methods. 相似文献
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Herbert J. Gans 《Ethnic and racial studies》2015,38(3):418-429
Exploring late-generation ethnicity automatically raises a long-ignored question: whether it will end and how: through what terminal stages and processes? In America, this question currently makes sense only for late-generation descendants of the European immigration wave that lasted roughly from the 1870s to 1924. However, answering it prepares the ground for eventually asking it also about late-generation ethnics in newer waves of immigration. 相似文献
35.
改良早期预警评分对转院转运工作影响的临床研究 总被引:1,自引:0,他引:1
目的 研究改良早期预警(MEWS)评分对转院转运工作的影响.方法 在转院转运工作中应用MEWS评分系统对患者进行病情评估,对比其应用前(对照组)、应用后(研究组)转院患者转运途中病情恶化的发生率、患者或家属满意度及医生、护士对实施MEWS评分转运管理模式前(对照组)、后(研究组)满意度的变化.结果 转院患者转运途中病情恶化发生率由应用前(对照组)的10.63%降至应用后(研究组)的3.74%,应用前、后比较差异有显著统计学意义(P<0.01);患方满意度则由96%提高至99%,医护人员对实施MEWS评分转运管理模式前、后的满意度由应用前的83.3%提高至应用后的95%,应用前、后比较均有显著性意义(P<0.05).结论 MEWS评分能对转院患者的病情进行比较客观、准确的评估,提高了医务人员的质量和医疗干预意识,从而有效降低转院患者转运途中的病情恶化发生率和提高院前医患双方的满意度,是转院转运工作中简便、快捷、客观、实用的病情评估方法和模式,值得推广应用. 相似文献
36.
通过PCR方法,将禽网状内皮组织增殖病病毒(REV)的长末端重复序列(LTR)扩增并克隆进pUC-18质粒多克隆位点(MCS)的EcoR I和Sac I之间,并以BGH基因的多聚腺苷酸序列作为终止子克隆到SphI~HindIII之间,构建成重组质粒pUC-LTR。将GFP基因和REV囊膜糖蛋白gp90基因分别克隆到pUC-LTR载体中,获得质粒pUC-LTR-GFP和质粒pUC-LTR-gp90。重组质粒经转染48h,能够检测到外源基因的表达。本研究提示,REVLTR能够作为启动子构建表达质粒。 相似文献
37.
Macarena Sahores Alessandro Prinetti Francesco Blasi Sandro Sonnino 《生物化学与生物物理学报:生物膜》2008,1778(1):250-259
UPAR is a GPI anchored protein, which is found in both lipid rafts and in more fluid regions of the plasma membrane. We have studied the role of the ligand uPA on uPAR localization and on the composition of the lipid membrane microdomains. We have analyzed the glycosphingolipid environment of uPAR in detergent resistant membrane (DRM) fractions prepared by cell lysis with 1% Triton X-100 and fractionated by sucrose gradient centrifugation obtained from HEK293-uPAR cells. The uPAR specific lipid membrane microdomain has been separated from the total DRM fraction by immunoprecipitation with an anti-uPAR specific antibody under conditions that preserve membrane integrity. We have also tested uPA-induced ERK phosphorylation in the presence of methyl-β-cyclodextrin, which is known to disrupt lipid rafts by sequestering cholesterol from such domains. Our results show that uPAR is partially associated with DRM and this association is increased by ligands, is independent of the catalytic activity of uPA, and is required for intracellular signalling. In the absence of ligands, uPAR experiences a lipid environment very similar to that of total DRM, enriched in sphingomyelin and glycosphingolipids. However, after treatment of cells with uPA or ATF the lipid environment is strongly impoverished of neutral glycosphingolipids. 相似文献
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目的:探讨香丹注射液治疗急性冠脉综合征血清C-反应蛋白、氨基末端脑钠肽以及心肌酶学的影响。方法:收集我院心内科收治的急性冠脉综合征患者66例,随机分为试验组和对照组,各33例。对照组予以阿司匹林片和硫酸氢氯吡格雷片治疗,试验组在对照组基础上予以香丹注射液治疗。观察并比较两组患者的临床疗效、血清肌钙蛋白T、C-反应蛋白、氨基末端脑钠肽、心肌酶学、不良反应以及心脏事件发生情况。结果:试验组临床总有效率高于对照组(P0.05)。治疗后两组肌钙蛋白T、C反应蛋白以及氨基末端脑钠肽水平降低,且试验组低于对照组(P0.05)。治疗后两组肌酸激酶同工酶、肌酸激酶、天门冬氨酸转移酶以及乳酸脱氢酶水平降低,且试验组低于对照组(P0.05)。试验组心绞痛发作次数、心肌缺血时间以及室性早搏次数较对照组相比显著降低(P0.05)。两组不良反应比较,差异无统计学意义(P0.05)。术后1个月内试验组心脏事件发生率显著低于对照组,差异有统计学意义(P0.05)。结论:香丹注射液治疗急性冠脉综合征的疗效显著,抑制炎症反应,安全性较高,降低心脏事件发生率,适宜临床应用推广。 相似文献
40.
Alternative operation models for using a feed‐in terminal as a part of the forest chip supply system for a CHP plant 下载免费PDF全文
Kari Väätäinen Robert Prinz Jukka Malinen Juha Laitila Lauri Sikanen 《Global Change Biology Bioenergy》2017,9(11):1657-1673
The fuel supply of forest chips has to adapt to the annual fluctuations of power and heat generation. This creates inefficiency and unbalances the capacity utilization of the fuel supply fleet in the direct fuel supplies from roadside storages to power and heat generation. Terminals can offer an alternative approach for the fleet management of fuel supplies in terms of smoothing the unbalanced fleet use towards more even year‐round operations. The aim of the study was to compare the supply costs of a conventional direct forest chip supply to an alternative fuel supply with the use of a feed‐in terminal using the discrete‐event simulation method. The influences of the terminal location, terminal investment cost, outbound terminal transport method, terminal truck utilization and quality changes of terminal‐stored forest chips for the fuel supply cost were studied in the case environment. By introducing a feed‐in terminal and a shuttle truck for the transports of terminal‐stored forest chips, the total supply cost was 1.4% higher than the direct fuel supply scenario. In terminal scenarios, the supply costs increased 1–2% if the cost of the terminal investment increased 30%, the distance to the terminal increased from 5 to 30 km or the total annual use of a terminal truck decreased 1500 h. Moreover, a 1 per cent point per month increase in the dry matter loss of terminal‐stored chips increased the total supply cost 1%. The study revealed that with the relatively low additional cost, the feed‐in terminal can be introduced to the conventional forest chip supply. Cost compensation can be gained through the higher annual use of a fuel supply fleet and more secured fuel supply to power plants by decreasing the need for supplement fuel, which can be more expensive at a time of the highest fuel demand. 相似文献