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61.
K. F. Dzerzhinskii F. N. Shkil Belay Abdissa Wondie Zelalem M. V. Mina 《Journal of Ichthyology》2007,47(8):639-646
Direct observations on three forms (morph types) of spawning barbs, considered by some authors as different species, were
carried out in September–October 2005 at the Gumara River and its small tributary, the Ducalit, in the Lake Tana basin. The
spawning barbs were sampled using cast nets. Barbs of different morphotypes composed common spawning aggregations and were
caught together. It is likely that troutlike females mate extensively with intermedius males and, probably, with bigmouth
small-eye males. Experiments in artificial fertilization and rearing showed that, during the embryonic period, there was no
increase in mortality of progeny from crosses of barbs of different morphotypes, in comparison with homonomic crosses, thus
suggesting an absence of postzygotic reproductive isolation between the morphotypes. At the same time, mortality of progeny
from crossing barbs with Varicorhinus beso Rüppell, 1836 was very high during the earliest stages of development, suggesting strong, even if incomplete, reproductive
isolation ensured by postzygotic mechanisms.
Published in Voprosy Ikhtiologii, 2007, Vol. 47, No. 5, pp. 676–683.
The article was translated by the authors. 相似文献
62.
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64.
Haselton MG Mortezaie M Pillsworth EG Bleske-Rechek A Frederick DA 《Hormones and behavior》2007,51(1):40-45
Humans differ from many other primates in the apparent absence of obvious advertisements of fertility within the ovulatory cycle. However, recent studies demonstrate increases in women's sexual motivation near ovulation, raising the question of whether human ovulation could be marked by observable changes in overt behavior. Using a sample of 30 partnered women photographed at high and low fertility cycle phases, we show that readily-observable behaviors - self-grooming and ornamentation through attractive choice of dress - increase during the fertile phase of the ovulatory cycle. At above-chance levels, 42 judges selected photographs of women in their fertile (59.5%) rather than luteal phase (40.5%) as "trying to look more attractive." Moreover, the closer women were to ovulation when photographed in the fertile window, the more frequently their fertile photograph was chosen. Although an emerging literature indicates a variety of changes in women across the cycle, the ornamentation effect is striking in both its magnitude and its status as an overt behavioral difference that can be easily observed by others. It may help explain the previously documented finding that men's mate retention efforts increase as their partners approach ovulation. 相似文献
65.
Characterization of the centromere and peri-centromere retrotransposons in Brassica rapa and their distribution in related Brassica species 总被引:2,自引:0,他引:2
Lim KB Yang TJ Hwang YJ Kim JS Park JY Kwon SJ Kim J Choi BS Lim MH Jin M Kim HI de Jong H Bancroft I Lim Y Park BS 《The Plant journal : for cell and molecular biology》2007,49(2):173-183
We report the identification and characterization of the major repeats in the centromeric and peri-centromeric heterochromatin of Brassica rapa. The analysis involved the characterization of 88 629 bacterial artificial chromosomes (BAC) end sequences and the complete sequences of two BAC clones. We identified centromere-specific retrotransposons of Brassica (CRB) and various peri-centromere-specific retrotransposons (PCRBr). Three copies of the CRB were identified in one BAC clone as nested insertions within a tandem array of 24 copies of a 176 bp centromeric repeat, CentBr. A complex mosaic structure consisting of nine PCRBr elements and large blocks of 238 bp degenerate tandem repeats (TR238) were found in or near a derivative of 5S-25S rDNA sequences. The chromosomal positions of selected repeats were determined using in situ hybridization. These revealed that CRB is a major component of all centromeres in three diploid Brassica species and their allotetraploid relatives. However, CentBr was not detected in the most distantly related of the diploid species analyzed, B. nigra. PCRBr and TR238 were found to be major components in the peri-centromeric heterochromatin blocks of four chromosomes of B. rapa. These repetitive elements were not identified in B. oleracea or B. nigra, indicating that they are A-genome-specific. GenBank accession numbers: KBrH001P13 (AC 166739); KBrH015B20 (AC 166740); end sequences of KBrH BAC library (CW 978640 - CW 988843); end sequences of KBrS BAC library (DU 826965 - DU 835595); end sequences of KBrB BAC library (DX 010661 - DX 083363). 相似文献
66.
The three-dimensional structure of the Moorella thermoacetica selenocysteine insertion sequence RNA hairpin and its interaction with the elongation factor SelB 下载免费PDF全文
Beribisky AV Tavares TJ Amborski AN Motamed M Johnson AE Mark TL Johnson PE 《RNA (New York, N.Y.)》2007,13(11):1948-1956
Incorporation of the amino acid selenocysteine into a growing protein chain involves the interaction between a hairpin in the mRNA termed the selenocysteine insertion sequence (SECIS) and the special elongation factor SelB. Here we present the structure of the SECIS from the thermophilic organism Moorella thermoacetica (SECIS-MT) determined using nuclear magnetic resonance (NMR) spectroscopy. The SECIS-MT hairpin structure contains a pentaloop with the first and fourth nucleotides of the loop forming a noncanonical GC base pair; the fifth loop nucleotide is bulged out and unstructured. The G and U in positions two and three are on opposite sides of the loop and solvent exposed. The backbone resonances of the SECIS-binding domain from the M. thermoacetica SelB protein were assigned, and the degree of chemical shift perturbations that occur upon SECIS binding were mapped onto the structure of the complex. We demonstrate that a region in the third winged-helix domain of SelB, not previously implicated in binding, is affected by SECIS binding. 相似文献
67.
Daud NH Kariwa H Tanikawa Y Nakamura I Seto T Miyashita D Yoshii K Nakauchi M Yoshimatsu K Arikawa J Takashima I 《Microbiology and immunology》2007,51(11):1081-1090
Hokkaido virus (HOKV) is a member of the genus Hantavirus, in the family Bunyaviridae. To investigate HOKV infection in the host Myodes rufocanus, the grey red-backed vole, 199 animals were captured at Tobetsu (October 2004 and July 2005) and Nakagawa (October 2004) in Hokkaido, Japan, for detection of antibody, antigen, and viral RNA. In the surveys in Tobetsu (2004) and Nakagawa (2004), seropositive animals were detected at a frequency of 6.0% (5/84) and 10.4% (5/48), respectively. No seropositive animals were detected in Tobetsu in 2005. Seroprevalence in males in Tobetsu and Nakagawa in 2004 was 25% (1/4) and 45.5% (5/11), respectively, which was higher than in females, at 5.0% (4/80) and 0% (0/37), respectively (P<0.01). These results suggest that male animals play an important role in the maintenance of HOKV in M. rufocanus. Two females were seronegative but viral RNA-positive, indicating that these animals had acute infections before antibody was produced. Another five infected animals in Nakagawa were all male and had high levels of antibodies and viral RNA, suggesting that they had persistent infections. Viral RNA copies in organs of infected animals in Nakagawa were quantified by real-time polymerase chain reaction. Two acutely infected animals had > or = 10 times the number of RNA copies in their lungs compared to those of persistently infected animals. In most cases, lungs or spleen had the highest RNA copy number, regardless of infection status. 相似文献
68.
Khajehdehi Mina Khalaj-Kondori Mohammad Hosseinpour Feizi Mohammad Ali 《Molecular biology reports》2022,49(7):6075-6084
Molecular Biology Reports - Aberrant expressions of long non-coding RNAs promote cancer development including colorectal cancer. Expression profiling of cancer-related lncRNAs may introduce new... 相似文献
69.
Gonçalves Renata C. Carvalho Celso Carneiro Michels Monique Abatti Mariane R. Manfredini Andressa Silva Milena C. Dominguini Diogo Steckert Amanda Mina Francielle Streck Emílio Budni Josiane Dal-Pizzol Felipe 《Neurochemical research》2022,47(3):613-621
Neurochemical Research - Critical illness encompasses a wide spectrum of life-threatening clinical conditions requiring intensive care. Our objective was to evaluate cognitive, inflammatory and... 相似文献
70.
Gavin Charlesworth Plamena?R. Angelova Fernando Bartolomé-Robledo Mina Ryten Daniah Trabzuni Maria Stamelou Andrey?Y. Abramov Kailash?P. Bhatia Nicholas?W. Wood 《American journal of human genetics》2015,96(4):657-665
Reports of primary isolated dystonia inherited in an autosomal-recessive (AR) manner, often lumped together as “DYT2 dystonia,” have appeared in the scientific literature for several decades, but no genetic cause has been identified to date. Using a combination of homozygosity mapping and whole-exome sequencing in a consanguineous kindred affected by AR isolated dystonia, we identified homozygous mutations in HPCA, a gene encoding a neuronal calcium sensor protein found almost exclusively in the brain and at particularly high levels in the striatum, as the cause of disease in this family. Subsequently, compound-heterozygous mutations in HPCA were also identified in a second independent kindred affected by AR isolated dystonia. Functional studies suggest that hippocalcin might play a role in regulating voltage-dependent calcium channels. The identification of mutations in HPCA as a cause of AR primary isolated dystonia paves the way for further studies to assess whether “DYT2 dystonia” is a genetically homogeneous condition or not. 相似文献