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661.
662.
Isamu Murakoshi Masanao Watanabe Joju Haginiwa Shigeru Ohmiya Hirotaka Otomasu 《Phytochemistry》1982,21(6):1470-1471
A new lupin alkaloid, (?)-N-ethylcytisine, was isolated from the fresh flowers of Echinosophora koreensis. Its structure has been confirmed b 相似文献
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Gima H Ohgi S Morita S Karasuno H Fujiwara T Abe K 《Journal of physiological anthropology》2011,30(5):179-186
This study's aim was to evaluate the characteristics of newborn and young infants' spontaneous lower extremity movements by using dynamical systems analysis. Participants were 8 healthy full-term newborn infants (3 boys, 5 girls, mean birth weight and gestational age were 3070.6 g and 39 weeks). A tri-axial accelerometer measured limb movement acceleration in 3-dimensional space. Movement acceleration signals were recorded during 200 s from just below the ankle when the infant was in an active alert state and lying supine (sampling rate 200 Hz). Data were analyzed linearly and nonlinearly. As a result, the optimal embedding dimension showed more than 5 at all times. Time dependent changes started at 6 or 7, and over the next four months decreased to 5 and from 6 months old, increased. The maximal Lyapnov exponent was positive for all segments. The mutual information is at its greatest range at 0 months. Between 3 and 4 months the range in results is narrowest and lowest in value. The mean coefficient of correlation for the x-axis component was negative and y-axis component changed to a positive value between 1 month old and 4 months old. Nonlinear time series analysis suggested that newborn and young infants' spontaneous lower extremity movements are characterized by a nonlinear chaotic dynamics with 5 to 7 embedding dimensions. Developmental changes of an optimal embedding dimension showed a U-shaped phenomenon. In addition, the maximal Lyapnov exponents were positive for all segments (0.79-2.99). Infants' spontaneous movement involves chaotic dynamic systems that are capable of generating voluntary skill movements. 相似文献
666.
Chutiwitoonchai N Hiyoshi M Mwimanzi P Ueno T Adachi A Ode H Sato H Fackler OT Okada S Suzu S 《PloS one》2011,6(11):e27696
Nef is a multifunctional HIV-1 protein that accelerates progression to AIDS, and enhances the infectivity of progeny viruses through a mechanism that is not yet understood. Here, we show that the small molecule compound 2c reduces Nef-mediated viral infectivity enhancement. When added to viral producer cells, 2c did not affect the efficiency of viral production itself. However, the infectivity of the viruses produced in the presence of 2c was significantly lower than that of control viruses. Importantly, an inhibitory effect was observed with Nef(+) wild-type viruses, but not with viruses produced in the absence of Nef or in the presence of proline-rich PxxP motif-disrupted Nef, both of which displayed significantly reduced intrinsic infectivity. Meanwhile, the overexpression of the SH3 domain of the tyrosine kinase Hck, which binds to a PxxP motif in Nef, also reduced viral infectivity. Importantly, 2c inhibited Hck SH3-Nef binding, which was more marked when Nef was pre-incubated with 2c prior to its incubation with Hck, indicating that both Hck SH3 and 2c directly bind to Nef and that their binding sites overlap. These results imply that both 2c and the Hck SH3 domain inhibit the interaction of Nef with an unidentified host protein and thereby reduce Nef-mediated infectivity enhancement. The first inhibitory compound 2c is therefore a valuable chemical probe for revealing the underlying molecular mechanism by which Nef enhances the infectivity of HIV-1. 相似文献
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Noriaki Yoshida Miyo Oda Yoshiaki Kuroda Yuta Katayama Yoshiko Okikawa Taro Masunari Megumu Fujiwara Takashi Nishisaka Naomi Sasaki Yoshito Sadahira Keichiro Mihara Hideki Asaoku Hirotaka Matsui Masao Seto Akiro Kimura Koji Arihiro Akira Sakai 《PloS one》2013,8(11)
Elevated soluble interleukin-2 receptor (sIL-2R) in sera is observed in patients with malignant lymphoma (ML). Therefore, sIL-2R is commonly used as a diagnostic and prognostic marker for ML, but the mechanisms responsible for the increase in sIL-2R levels in patients with B-cell lymphomas have not yet been elucidated. We first hypothesized that lymphoma cells expressing IL-2R and some proteinases such as matrix metalloproteinases (MMPs) in the tumor microenvironment can give rise to increased sIL-2R in sera. However, flow cytometric studies revealed that few lymphoma cells expressed IL-2R α chain (CD25) in diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL), and most CD25-expressing cells in the tumor were T-cells. Distinct correlations between CD25 expression on B-lymphoma cells and sIL-2R levels were not observed. We then confirmed that MMP-9 plays an important role in producing sIL-2R in functional studies. Immunohistochemical (IHC) analysis also revealed that MMP-9 is mainly derived from tumor-associated macrophages (TAMs). We therefore evaluated the number of CD68 and CD163 positive macrophages in the tumor microenvironment using IHC analysis. A positive correlation between the levels of sIL-2R in sera and the numbers of CD68 positive macrophages in the tumor microenvironment was confirmed in FL and extranodal DLBCL. These results may be useful in understanding the pathophysiology of B-cell lymphomas. 相似文献
668.
Lily Paemka Vinit B. Mahajan Jessica M. Skeie Levi P. Sowers Salleh N. Ehaideb Pedro Gonzalez-Alegre Toshikuni Sasaoka Hirotaka Tao Asuka Miyagi Naoto Ueno Keizo Takao Tsuyoshi Miyakawa Shu Wu Benjamin W. Darbro Polly J. Ferguson Andrew A. Pieper Jeremiah K. Britt John A. Wemmie Danielle S. Rudd Thomas Wassink Hatem El-Shanti Heather C. Mefford Gemma L. Carvill J. Robert Manak Alexander G. Bassuk 《PloS one》2013,8(12)
The frequent comorbidity of Autism Spectrum Disorders (ASDs) with epilepsy suggests a shared underlying genetic susceptibility; several genes, when mutated, can contribute to both disorders. Recently, PRICKLE1 missense mutations were found to segregate with ASD. However, the mechanism by which mutations in this gene might contribute to ASD is unknown. To elucidate the role of PRICKLE1 in ASDs, we carried out studies in Prickle1+/− mice and Drosophila, yeast, and neuronal cell lines. We show that mice with Prickle1 mutations exhibit ASD-like behaviors. To find proteins that interact with PRICKLE1 in the central nervous system, we performed a yeast two-hybrid screen with a human brain cDNA library and isolated a peptide with homology to SYNAPSIN I (SYN1), a protein involved in synaptogenesis, synaptic vesicle formation, and regulation of neurotransmitter release. Endogenous Prickle1 and Syn1 co-localize in neurons and physically interact via the SYN1 region mutated in ASD and epilepsy. Finally, a mutation in PRICKLE1 disrupts its ability to increase the size of dense-core vesicles in PC12 cells. Taken together, these findings suggest PRICKLE1 mutations contribute to ASD by disrupting the interaction with SYN1 and regulation of synaptic vesicles. 相似文献
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670.
Synthesis and structure-activity relationship of tricyclic carboxylic acids as novel anti-histamines
Kubota K Kurebayashi H Miyachi H Tobe M Onishi M Isobe Y 《Bioorganic & medicinal chemistry》2011,19(9):3005-3021
A series of tricyclic carboxylic acids having 6-amino-pyrimidine-2,4(1H,3H)-dione with piperazino or homopiperazino moiety linked by propylene, were synthesized and evaluated for their affinity toward human histamine H(1) receptor and Caco-2 cell permeability. Selected compounds were further evaluated for their oral anti-histaminic activity in mice, bioavailability in rats, and their anti-inflammatory activity in mice OVA-induced biphasic cutaneous reaction model. Among the compounds tested, dibenzoxazepine carboxylic acid 13b showed both histamine H(1) receptor antagonistic activity and anti-inflammatory activity in vivo. In addition, 13b exhibited low affinity toward α(1) receptor and low occupancy of H(1) receptor in the brain. It is therefore, believed that 13b is a potential candidate for development as 3rd generation anti-histamine. 相似文献