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941.
942.
Fujimoto T Machida T Tsunoda T Doi K Ota T Kuroki M Shirasawa S 《Biochemical and biophysical research communications》2011,(2):282-286
Concanavalin A (ConA), a Ca2+/Mn2+-dependent and mannose/glucose-binding legume lectin, has drawn a rising attention for its remarkable anti-proliferative and anti-tumor activities to a variety of cancer cells. ConA induces programmed cell death via mitochondria-mediated, P73-Foxo1a-Bim apoptosis and BNIP3-mediated mitochondrial autophagy. Through IKK-NF-κB-COX-2, SHP-2-MEK-1-ERK, and SHP-2-Ras-ERK anti-angiogenic pathways, ConA would inhibit cancer cell survival. In addition, ConA stimulates cell immunity and generates an immune memory, resisting to the same genotypic tumor. These biological findings shed light on new perspectives of ConA as a potential anti-neoplastic agent targeting apoptosis, autophagy and anti-angiogenesis in pre-clinical or clinical trials for cancer therapeutics. 相似文献
943.
Fujimoto T Machida T Tanaka Y Tsunoda T Doi K Ota T Okamura T Kuroki M Shirasawa S 《Biochemical and biophysical research communications》2011,(2):214-443
Three inositol 1,4,5-trisphosphate receptor (IP3R) subtypes are differentially expressed among tissues and function as the Ca2+ release channel on specialized endoplasmic reticulum (ER) membranes. The proper subcellular localization of IP3R is crucial for its proper function, but this molecular mechanism is unclear. KRAS-induced actin-interacting protein (KRAP) was originally identified as a cancer-related molecule, and is involved in the regulation of whole-body energy homeostasis and pancreatic exocrine system. We herein identified IP3R as an associated molecule with KRAP in vivo, and the association was validated by the co-immunoprecipitation and confocal immunostaining studies in mouse tissues including liver and pancreas. The association of KRAP with IP3R was also observed in the human epithelial cell lines including HCT116, HeLa and HEK293 cells. Intriguingly, KRAP interacts with distinct subtypes of IP3R in a tissue-dependent manner, i.e. IP3R1 and IP3R2 in the liver and IP3R2 and IP3R3 in the pancreas. The NH2-terminal amino acid residues 1–610 of IP3R are critical for the association with KRAP and KRAP–IP3R complex resides in a specialized ER but not a typical reticular ER. Furthermore, the localization of particular IP3R subtypes in tissues from KRAP-deficient mice is obviously disturbed, i.e. IP3R1 and IP3R2 in the liver and IP3R2 and IP3R3 in the pancreas. These findings demonstrate that KRAP physically associates with IP3R and regulates the proper localization of IP3R in the epithelial cells in vivo and cultured cells, and might shed light on the Ca2+ signaling underlying physiological cellular programs, cancer development and metabolism-related diseases. 相似文献
944.
Interleukin-21 (IL-21) is a pleiotropic cytokine that regulates T-cell, B-cell, NK-cell, and myeloid-cell functions. IL-21 binds with its cognate receptor complex, which consists of the IL-21 receptor (IL-21R) and the common gamma chain. We identified a novel IL-21R-binding molecule, WSB-1, which contains WD-40 repeats and a SOCS-box domain. WSB-1 associates with the middle part of intracytoplasmic region of IL-21R and enhances the maturation of IL-21R from N-linked glycosylated form to fully glycosylated mature form. Furthermore, WSB-1 moderates IL-21R degradation. Taken together, our present study suggests that WSB-1 has a role in the tuning of the maturation and degradation of IL-21R. 相似文献
945.
Temperature and pH effects were studied for stability, structural organization, fluidity and permeability of vesicles from a polar lipid methanol fraction isolated from the Aeropyrum pernix. We determined the permeability of C25,25 liposomes using fluorescence intensity of released calcein. At pH 7.0 and 9.0, and from 85 °C to 98 °C, only 10% of entrapped calcein was released. After 10 h at 90 °C, calcein release reached 27%, independent of pH. Fluorescence anisotropy measurements of hydrophobic probe 1,6-diphenyl-1,3,5-hexatriene revealed gradual changes up to 60 °C. At higher temperatures, the anisotropy did not change significantly. Fluorescence alone did not provide detailed and direct structural information about these C25,25 liposomes, so we used electron paramagnetic resonance spectroscopy (EPR) and differential scanning calorimetry (DSC). From EPR spectra, mean membrane fluidity determined according to maximal hyperfine splitting and empirical correlation times showed continuous increases with temperature. Computer simulation of EPR spectra showed heterogeneous membranes of these C25,25 liposomes: at low temperatures, they showed three types of membrane regions characterized by different motional modes. Above 65 °C, the membrane becomes homogeneous with only one fluid-like region. DSC thermograms of C25,25 liposomes reveal a very broad and endothermic transition in the temperature range from 0 °C to 40 °C. 相似文献
946.
The Origin of Southeastern Asian Triploid Edible Canna (
Canna discolor
Lindl.) Revealed by Molecular Cytogenetical Study.
Canna discolor Lindl. (Cannaceae), commonly known as edible canna, is often cultivated in Southeastern Asia for its starchy rhizomes. Based
on morphological and karyological features, it is thought to be an allotriploid plant originated from hybridization between
the closely allied C. coccinea Mill., C. patens Roscoe, C. plurituberosa T. Koyama & Nb. Tanaka, C. speciosa Roscoe, or C. indica L. In this study, to clarify the origin of triploid edible canna, physical mapping of 5S and 18S rDNA probes in C. discolor and its closely related five putative parental species was conducted. Fluorescence in situ hybridization (FISH) technique
provided a useful chromosomal marker for discriminating among the diploid putative parental Canna species, and supported the hybrid origin of C. discolor between C. indica var. indica and C. plurituberosa. 相似文献
947.
Variability in thallus morphology is common in red seaweeds. Two co-occurring forms have been described for Chondracanthus chamissoi based mainly on blade width. To determine whether two distinct forms or a range of intermediate morphologies occur in C. chamissoi, thalli were collected from three localities in southern Chile in autumn–winter, repeating the sampling in one locality in spring and in summer. In each occasion, individual sporophytic and male and female gametophytic clumps were collected, and the longest blade with intact apex from each clump was evaluated. Blade length, width, density of spines, axis curvature and thickness, and pinnule length and width were evaluated in each blade. Principal components analyses separated two groups of thalli, one group with narrow, thick, and curved (concavo-convex) blades, with few spines consistent with f. lessonii, and another with broad, thin, and flat blades, with many spines consistent with f. chauvinii. These variables also had bimodal frequency distributions. Pinnule measurements were mainly associated with differences among sporophytes and gametophytes. Age (length), phase of the life cycle, and sex were not related to the forms. Furthermore, thalli of both forms were collected side by side in the study sites and throughout the year so the occurrence of the two forms was not attributable to local environmental conditions. In this species, secondary basal disks are produced after attachment of apexes to the substratum. These disks may produce blades with a modified morphology in a way similar to proliferations and regenerations described for Schottera nicaeensis. 相似文献
948.
Shuhei Ota Haruyo Yamaguchi Faustine Vanel Shigeshi Fuchida Hiroshi Koshikawa Takahiro Yamagishi Hiroshi Yamamoto Masanobu Kawachi 《Phycological Research》2020,68(1):41-49
Seafloor massive sulfide (SMS) deposits are the target of available metallic resources. The toxic impacts of leachable metals from hydrothermal ore by mining operations in marine environments are a concern. However, ecotoxicological knowledge about marine algae, and particularly open ocean species, is still limited. Here, we evaluated the toxic effects of three leachable metals (i.e. Zn, Cu, and Pb) on seven marine algae, including cyanobacteria and eukaryotes, by a delayed fluorescence method. Cyanobacterial Synechococcus and Cyanobium species were sensitive to Zn and Cu, while eukaryotic algae showed various responses to heavy metal species. The prasinophycean Bathycoccus prasinos NIES‐2670 was sensitive to all metal species; this strain is a potential test strain to detect the leachable metals. A co‐culture experiment showed that the impact on community structure varies depending on leachable metal species. This study demonstrates that surveys across multiple taxonomic groups are necessary to assess the impact of SMS‐mining operations on marine ecosystems as a whole. 相似文献
949.
Alireza Houshmandfar Noboru Ota Garry J. O'Leary Bangyou Zheng Yang Chen Sabine Tausz‐Posch Glenn J. Fitzgerald Richard Richards Greg J. Rebetzke Michael Tausz 《Global Change Biology》2020,26(7):4056-4067
Reducing the number of tillers per plant using a t iller in hibition (tin) gene has been considered as an important trait for wheat production in dryland environments. We used a spatial analysis approach with a daily time‐step coupled radiation and transpiration efficiency model to simulate the impact of the reduced‐tillering trait on wheat yield under different climate change scenarios across Australia's arable land. Our results show a small but consistent yield advantage of the reduced‐tillering trait in the most water‐limited environments both under current and likely future conditions. Our climate scenarios show that whilst elevated [CO2] (e[CO2]) alone might limit the area where the reduced‐tillering trait is advantageous, the most likely climate scenario of e[CO2] combined with increased temperature and reduced rainfall consistently increased the area where restricted tillering has an advantage. Whilst long‐term average yield advantages were small (ranged from 31 to 51 kg ha?1 year?1), across large dryland areas the value is large (potential cost‐benefits ranged from Australian dollar 23 to 60 MIL/year). It seems therefore worthwhile to further explore this reduced‐tillering trait in relation to a range of different environments and climates, because its benefits are likely to grow in future dry environments where wheat is grown around the world. 相似文献
950.
Masahito Hosokawa Hirotsugu Kenmotsu Yasuhiro Koh Tomoko Yoshino Takayuki Yoshikawa Tateaki Naito Toshiaki Takahashi Haruyasu Murakami Yukiko Nakamura Asuka Tsuya Takehito Shukuya Akira Ono Hiroaki Akamatsu Reiko Watanabe Sachiyo Ono Keita Mori Hisashige Kanbara Ken Yamaguchi Tsuyoshi Tanaka Tadashi Matsunaga Nobuyuki Yamamoto 《PloS one》2013,8(6)