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991.
992.
Mg-polymer of actin formed under the influence of -actinin 总被引:1,自引:0,他引:1
R Kamiya K Maruyama M Kuroda M Kawamura M Kikuchi 《Biochimica et biophysica acta》1972,256(1):120-131
993.
994.
Yuka Matsushita Hiroki Oota Barbara J. Welker Mary S. Pavelka Shoji Kawamura 《International journal of primatology》2014,35(1):71-87
Platyrrhine (New World) monkeys possess highly polymorphic color vision owing to allelic variation of the single-locus L/M opsin gene on the X chromosome. Most species consist of female trichromats and female and male dichromats. Howlers (genus Alouatta) are an exception; they are considered to be routinely trichromatic with L and M opsin genes juxtaposed on the X chromosome, as seen in catarrhine primates (Old World monkeys, apes, and humans). Yet it is not known whether trichromacy is invariable in howlers. We examined L/M opsin variation in wild howler populations in Costa Rica and Nicaragua (Alouatta palliata) and Belize (A. pigra), using fecal DNA. We surveyed exon 5 sequences (containing the diagnostic 277th and 285th residues for λmax) for 8 and 18 X chromosomes from Alouatta palliata and A. pigra, respectively. The wavelengths of maximal absorption (λmax) of the reconstituted L and M opsin photopigments were 564 nm and 532 nm, respectively, in both species. We found one M–L hybrid sequence with a recombinant 277/285 haplotype in Alouatta palliata and two L–M hybrid sequences in A. pigra. The λmax values of the reconstituted hybrid photopigments were in the range of 546~554 nm, which should result in trichromat phenotypes comparable to those found in other New World monkey species. Our finding of color vision variation due to high frequencies of L/M hybrid opsin genes in howlers challenges the current view that howlers are routine and uniform trichromats. These results deepen our understanding of the evolutionary significance of color vision polymorphisms and routine trichromacy and emphasize the need for further assessment of opsin gene variation as well as behavioral differences among subtypes of trichromacy. 相似文献
995.
Ayako Hasegawa Takuichi Sato Yasushi Hoshikawa Naoko Ishida Naoko Tanda Yoshiaki Kawamura Takashi Kondo Nobuhiro Takahashi 《Microbiology and immunology》2014,58(7):375-381
Postoperative pneumonia may occur when upper respiratory tract protective reflexes such as cough and/or swallowing reflexes are impaired; thus, silent aspiration of oral bacteria may be a causative factor in postoperative pneumonia. This study aimed to quantify and identify bacteria in intraoperative bronchial fluids and to evaluate the relationship between impairment of cough/swallowing reflexes and silent aspiration of oral bacteria in elderly patients. After obtaining informed consent, cough and swallowing reflexes were assessed using an ultrasonic nebulizer and a nasal catheter, respectively. Using a micro‐sampling probe, intraoperative bronchial fluids were collected from nine subjects with pulmonary carcinoma and cultured anaerobically on blood agar plates. After 7 days, CFUs were counted and isolated bacteria were identified by 16S rRNA gene sequencing. Four subjects (aged 71.0 ± 8.4 years) had impaired swallowing reflexes with normal cough reflexes, whereas five subjects (73.6 ± 6.5 years) had normal cough and swallowing reflexes. The bacterial counts (mean CFU ± SD) tended to be higher in intraoperative bronchial fluids of subjects with impaired swallowing reflexes ([5.1 ± 7.7] × 105) than in those of subjects with normal reflexes ([1.2 ± 1.9] × 105); however, this difference was not statistically significant. Predominant isolates from intraoperative bronchial fluids were Streptococcus (41.8%), Veillonella (11.4%), Gemella (8.9%), Porphyromonas (7.6%), Olsenella (6.3%) and Eikenella (6.3%). These findings indicate that intraoperative bronchial fluids contain bacteria, probably derived from the oral microbiota, and suggest that silent aspiration of oral bacteria occurs in elderly patients irrespective of impairment of swallowing reflex. 相似文献
996.
997.
Masahito Kawamura Jr. David N. Ruskin Jonathan D. Geiger Detlev Boison Susan A. Masino 《Journal of lipid research》2014,55(11):2254-2260
A high-fat low-carbohydrate ketogenic diet (KD) is an effective treatment for
refractory epilepsy, yet myriad metabolic effects in vivo have not been reconciled
clearly with neuronal effects. A KD limits blood glucose and produces ketone bodies
from β-oxidation of lipids. Studies have explored changes in ketone bodies
and/or glucose in the effects of the KD, and glucose is increasingly implicated in
neurological conditions. To examine the interaction between altered glucose and the
neural effects of a KD, we fed rats and mice a KD and restricted glucose in vitro
while examining the seizure-prone CA3 region of acute hippocampal slices. Slices from
KD-fed animals were sensitive to small physiological changes in glucose, and showed
reduced excitability and seizure propensity. Similar to clinical observations,
reduced excitability depended on maintaining reduced glucose. Enhanced glucose
sensitivity and reduced excitability were absent in slices obtained from KD-fed mice
lacking adenosine A1 receptors (A1Rs); in slices from normal
animals effects of the KD could be reversed with blockers of pannexin-1 channels,
A1Rs, or KATP channels. Overall, these studies reveal that a
KD sensitizes glucose-based regulation of excitability via purinergic mechanisms in
the hippocampus and thus link key metabolic and direct neural effects of the KD. 相似文献
998.
Manakorn Sukmak Suchinda Malaivijitnond Oliver Schülke Julia Ostner Yuzuru Hamada Worawidh Wajjwalku 《Primates; journal of primatology》2014,55(2):189-197
Human overpopulation, deforestation, invasion of agricultural areas, and livestock are the primary causes for population fragmentation of wildlife. The distribution range of species of the genus Macaca is constantly decreasing and becoming increasingly fragmented due to forest deterioration. Assamese macaques (M. assamensis) are classified as near threatened in the International Union for Conservation of Nature (IUCN) Red List of Threatened Animals (2008) and have been declared a protected wildlife animal according to Wildlife Preservation and Protection Act, B.E.2535 (1992) of Thailand. As studies of the population history and genetic diversity of Assamese macaques in Thailand are currently lacking, we aimed at a first investigation of their genetic diversity based on mitochondrial DNA [hypervariable regions 1 and 2 (HV1, HV2) and cytochrome B (CYTB) regions], as well as 15 microsatellite markers of five sampling sites distributed across Thailand. Our results indicate that Assamese macaques in Thailand are diverse, with eight maternal haplotypes and a low inbreeding coefficient in the Phu Khieo Wildlife Sanctuary (PKWS) population. Moreover, our phylogenetic and median-joining network analysis based on mitochondrial (mt)DNA suggests a population distribution in accordance with the evolutionary scenario proposed for M. sinica. Today, the population of Assamese macaques is fragmented, and conservation strategies are needed to ensure the maintenance of genetic diversity of this primate species. 相似文献
999.
1000.
Sophie T Williams Louise J Walport Richard J Hopkinson Sarah K Madden Rasheduzzaman Chowdhury Christopher J Schofield Akane Kawamura 《Epigenetics》2014,9(12):1596-1603
The JmjC-domain-containing 2-oxoglutarate-dependent oxygenases catalyze protein hydroxylation and Nε-methyllysine demethylation via hydroxylation. A subgroup of this family, the JmjC lysine demethylases (JmjC KDMs) are involved in histone modifications at multiple sites. There are conflicting reports as to the substrate selectivity of some JmjC oxygenases with respect to KDM activities. In this study, a panel of modified histone H3 peptides was tested for demethylation against 15 human JmjC-domain-containing proteins. The results largely confirmed known Nε-methyllysine substrates. However, the purified KDM4 catalytic domains showed greater substrate promiscuity than previously reported (i.e., KDM4A was observed to catalyze demethylation at H3K27 as well as H3K9/K36). Crystallographic analyses revealed that the Nε-methyllysine of an H3K27me3 peptide binds similarly to Nε-methyllysines of H3K9me3/H3K36me3 with KDM4A. A subgroup of JmjC proteins known to catalyze hydroxylation did not display demethylation activity. Overall, the results reveal that the catalytic domains of the KDM4 enzymes may be less selective than previously identified. They also draw a distinction between the Nε-methyllysine demethylation and hydroxylation activities within the JmjC subfamily. These results will be of use to those working on functional studies of the JmjC enzymes. 相似文献