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121.
Judit Bereczki Jnos P. Tth Gbor Sramk Zoltn Varga 《Journal of Zoological Systematics and Evolutionary Research》2014,52(1):32-43
The main goal of our research was to study comprehensively the differences between the two phenological forms of the socially parasitic and globally threatened Large Blue (Maculinea arion) in the Carpathian Basin using four character sets (mitochondrial sequences, allozymes, male genitalia and wing morphometrics). Comparative analyses of distance matrices, phylogenetic trees and ordination patterns have been applied. The genetic and morphometric patterns revealed by our studies were discordant. While we experienced a significant differentiation between the ‘spring’ and ‘summer type’ of M. arion in both wing and genital traits, the two phenological forms did not show any genetic differentiation on two mitochondrial loci and in allozymes. At the same time, all individuals were infected by Wolbachia. Although certain wing traits may not represent reliable tracers of phylogeny because of the particular adaptive significance, the wing characteristics involved in our research are probably determined genetically. Additionally, the significant differentiation of male genitalia also indicates incipient prezygotic isolation arising from phenological differentiation between the ‘spring and summer arion’. It is possible that all extant differences between the two forms are attributable to (1) different host‐ant use, (2) incipient speciation, (3) cytoplasmatic incompatibility (CI) by Wolbachia or the combination of these factors. In addition, discordant results indicate that the combined use of different approaches and data sets is strictly necessary to clarify systematic and evolutionary relationships. 相似文献
122.
ágnes Czikora Ibolya Rutkai Enik? T. Pásztor Andrea Szalai Róbert Pórszász Judit Boczán István édes Zoltán Papp Attila Tóth 《PloS one》2013,8(11)
Background and purpose
TRPV1 is expressed in sensory neurons and vascular smooth muscle cells, contributing to both pain perception and tissue blood distribution. Local desensitization of TRPV1 in sensory neurons by prolonged, high dose stimulation is re-engaged in clinical practice to achieve analgesia, but the effects of such treatments on the vascular TRPV1 are not known.Experimental approach
Newborn rats were injected with capsaicin for five days. Sensory activation was measured by eye wiping tests and plasma extravasation. Isolated, pressurized skeletal muscle arterioles were used to characterize TRPV1 mediated vascular responses, while expression of TRPV1 was detected by immunohistochemistry.Key results
Capsaicin evoked sensory responses, such as eye wiping (3.6±2.5 versus 15.5±1.4 wipes, p<0.01) or plasma extravasation (evans blue accumulation 10±3 versus 33±7 µg/g, p<0.05) were reduced in desensitized rats. In accordance, the number of TRPV1 positive sensory neurons in the dorsal root ganglia was also decreased. However, TRPV1 expression in smooth muscle cells was not affected by the treatment. There were no differences in the diameter (192±27 versus 194±8 µm), endothelium mediated dilations (evoked by acetylcholine), norepinephrine mediated constrictions, myogenic response and in the capsaicin evoked constrictions of arterioles isolated from skeletal muscle.Conclusion and implications
Systemic capsaicin treatment of juvenile rats evokes anatomical and functional disappearance of the TRPV1-expressing neuronal cells but does not affect the TRPV1-expressing cells of the arterioles, implicating different effects of TRPV1 stimulation on the viability of these cell types. 相似文献123.
Bohu??ObertEmail author László?Szabó Judit?Mitykó Anna?Pre?ová Beáta?Barnabás 《In vitro cellular & developmental biology. Plant》2005,41(6):775-782
Summary In tis androgenic response, maize is considered to be a recalcitrant plant. We used mechanically isolated microspores of maize
genotype A18 to establish a responsive microspore culture of maize. Morphological events occurring during the first days of
maize androgenesis in a microspore culture were observed and described, and some morphological markers for distinguishing
between embryogenic microspores and nonembryogenic microspores were identified. It was found that the enlargement of microspores
during the first days in culture and the ‘star-like’ organization of the cytoplasm inside the microspore are connected with
reprogramming of the developmental pathway in maize microspores. Some differences were also found in the surface wall architecture
of embryogenic microspores. Fertile plants were successfully recovered from microspore-originated structures. 相似文献
124.
Margarida Gairí Pilar Saiz Sergio Madurga Xavier Roig Judit Erchegyi Steven C Koerber Jean Claude Reubi Jean E Rivier Ernest Giralt 《Journal of peptide science》2006,12(2):82-91
The three-dimensional structure of a potent SSTR3-selective analogue of somatostatin, cyclo(3-14)H-Cys(3)-Phe(6)-Tyr(7)-D-Agl(8)(N(beta) Me, 2-naphthoyl)-Lys(9)-Thr(10)-Phe(11)-Cys(14)-OH (des-AA(1, 2, 4, 5, 12, 13)[Tyr(7), D-Agl(8)(N(beta) Me, 2-naphthoyl)]-SRIF) (peptide 1) has been determined by (1)H NMR in water and molecular dynamics (MD) simulations. The peptide exists in two conformational isomers differing mainly by the cis/trans isomerization of the side chain in residue 8. The structure of 1 is compared with the consensus structural motifs of other somatostatin analogues that bind predominantly to SSTR1, SSTR2/SSTR5 and SSTR4 receptors, and to the 3D structure of a non-selective SRIF analogue, cyclo(3-14)H-Cys(3)-Phe(6)-Tyr(7)-D-2Nal(8)-Lys(9)-Thr(10)-Phe(11)-Cys(14)-OH (des-AA(1, 2, 4, 5, 12, 13)[Tyr(7), D-2Nal(8)]-SRIF) (peptide 2). The structural determinant factors that could explain selectivity of peptide 1 for SSTR3 receptors are discussed. 相似文献
125.
Arindam Das Charumathi Pushparaj Judit Herreros Mireia Nager Ramon Vilella Manuel Portero Reinald Pamplona Xavier Matias‐Guiu Rosa M. Martí Carles Cantí 《Pigment cell & melanoma research》2013,26(6):874-885
We have recently reported that human melanoma cells express a variety of voltage‐gated calcium (Ca2+) channel types, including low‐voltage‐activated T‐type channels that play a significant role in melanoma cell cycle progression. Here, we challenged melanoma metastatic cells with T‐type channel blockers of clinical use and found a dual effect on cell viability: (i) a reduction in the proliferation rate, through a halt in the progression to the G1‐S phase; and (ii) a promotion of cell death that was partially dependent on the activation of caspases. An in‐depth analysis of the death process showed that the apoptotic pathway is preceded by endoplasmic reticulum stress and the subsequent inhibition of the basal macroautophagy which is active in these cells. The effects of pharmacological blockers on Ca2+ homeostasis, autophagy, and cell death were mimicked by T‐type channel gene silencing. These results provide the basis for a new pharmacological and/or gene silencing approach toward tackling melanoma metastasis. 相似文献
126.
Árpád Kovács Judit Kalász Enikő T. Pásztor Attila Tóth Zoltán Papp Naranjan S. Dhalla Judit Barta 《Molecular and cellular biochemistry》2017,424(1-2):57-67
C1ql-like (C1QL)-1 and -4 proteins are encoded by homologous genes that are highly expressed in brain and adipose tissues. However, functional properties of C1QL proteins outside of the brain and adipocytes remain unknown. Here, we report that the globular domain of C1ql1/Ctrp14 and C1ql4/Ctrp11 proteins directly stimulate the angiogenesis of endothelial cells. In this study, soluble C1ql1/CTRP14 and C1ql4/Ctrp11 proteins, produced in prokaryote expression system, are co-cultured with human umbilical vein endothelium cells (HUVECs), which phenotype is identified with von Willebrand factor antibody. C1ql1/Ctrp14 and C1ql4/Ctrp11 promote the migration and capillary tube formation of HUVECs in a dose-dependent manner. During this process, phosphorylation of c-Raf, MEK1/2, ERK1/2, and p90RSK are activated by C1ql1/Ctrp14 and C1ql4/Ctrp11. MEK1/2 inhibitor, U0126, blocks C1ql1/Ctrp14-, and C1ql4/Ctrp11-induced capillary tube formation and cell migration. Moreover, the immunoreactivity of the receptor of C1QL1-C1QL4, brain-specific angiogenesis inhibitor 3 (BAI3), is detected in HUVECs, suggesting that BAI3 may mediate C1QL1/CTRP14- and C1QL4/CTRP11-induced angiogenesis. Meanwhile, C1ql1/Ctrp14 and C1ql4/Ctrp11 exposure also causes a stimulatory response of angiogenesis in chick yolk sac membrane. These data demonstrate that C1ql1/Ctrp14 and C1ql4/Ctrp11 stimulate the new blood vessel growth by activation of ERK1/2 signal pathway. The proangiogenic activity of C1ql1/Ctrp14 and C1ql4/Ctrp11 provides novel insights into the new opportunities for therapeutic intervention by targeting C1QLs in tumorigenesis, tissue regeneration, and recovery of ischemic heart disease. 相似文献
127.
128.
Dobránszki Judit Hidvégi Norbert Gulyás Andrea Teixeira da Silva Jaime A. 《Plant molecular biology》2019,100(4-5):511-525
Plant Molecular Biology - In response to an ultrasound pulse, several hundred DEGs, including in response to stress, were up- or down-regulated in in vitro potato plantlets. Despite this abiotic... 相似文献
129.
Sabrina Sacconi Richard J.L.F. Lemmers Judit Balog Patrick J. van der Vliet Pauline Lahaut Merlijn P. van Nieuwenhuizen Kirsten R. Straasheijm Rashmie D. Debipersad Marianne Vos-Versteeg Leonardo Salviati Alberto Casarin Elena Pegoraro Rabi Tawil Egbert Bakker Stephen J. Tapscott Claude Desnuelle Silvère M. van der Maarel 《American journal of human genetics》2013
130.
Pavel Uhrin Dongdong Wang Andrei Mocan Birgit Waltenberger Johannes M. Breuss Devesh Tewari Judit Mihaly-Bison Łukasz Huminiecki Rafał R. Starzyński Nikolay T. Tzvetkov Jarosław Horbańczuk Atanas G. Atanasov 《Biotechnology advances》2018,36(6):1608-1621
Many natural products have been so far tested regarding their potency to inhibit vascular smooth muscle cell proliferation, a process involved in atherosclerosis, pulmonary hypertension and restenosis. Compounds studied in vitro and in vivo as VSMC proliferation inhibitors include, for example indirubin-3′-monoxime, resveratrol, hyperoside, plumericin, pelargonidin, zerumbone and apamin. Moreover, taxol and rapamycin, the most prominent compounds applied in drug-eluting stents to counteract restenosis, are natural products. Numerous studies show that natural products have proven to yield effective inhibitors of vascular smooth muscle cell proliferation and ongoing research effort might result in the discovery of further clinically relevant compounds. 相似文献