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141.
Wesley L Hung Christine Hwang ShangBang Gao Jyothsna Chitturi Ying Wang Hang Li Jean‐Louis Bessereau Mei Zhen 《The EMBO journal》2013,32(12):1745-1760
A neuronal F‐box protein FSN‐1 regulates Caenorhabditis elegans neuromuscular junction development by negatively regulating DLK‐mediated MAPK signalling. In the present study, we show that attenuation of insulin/IGF signalling also contributes to FSN‐1‐dependent synaptic development and function. The aberrant synapse morphology and synaptic transmission in fsn‐1 mutants are partially and specifically rescued by reducing insulin/IGF‐signalling activity in postsynaptic muscles, as well as by reducing the activity of EGL‐3, a prohormone convertase that processes agonistic insulin/IGF ligands INS‐4 and INS‐6, in neurons. FSN‐1 interacts with, and potentiates the ubiquitination of EGL‐3 in vitro, and reduces the EGL‐3 level in vivo. We propose that FSN‐1 may negatively regulate insulin/IGF signalling, in part, through EGL‐3‐dependent insulin‐like ligand processing. 相似文献
142.
Aerobic plate counts (APC), coliforms, Bacillus cereus, Escherichia coli and eight foodborne pathogens were tested in 1008 cheap and junk foods, including candies, dried cakes, chewing gum, chocolate, dried and seasoned seafood, ice cream, and sugary foods. APCs were positive for 342 samples (33·9%), and the majority of the counts were 2–3 log CFU g?1 or ml?1 (average: 1·10 log CFU g?1 or ml?1). Most samples (97·3%) contained no coliforms (average: 0·07 log CFU g?1 or ml?1). Bacillus cereus was detected in 68 samples (average: 0·14 log CFU g?1 or ml?1). Escherichia coli and Listeria monocytogenes were detected in 6 and 1 samples, respectively, whereas other foodborne pathogens were not isolated. The highest bacterial counts were associated with dried and seasoned seafood products and dried cakes, suggesting that appropriate regulations of these food types should be considered. Cheap and junk foods were produced mainly in developing countries, but there were no significant differences in the bacterial counts among different countries of origin. The presence of foodborne pathogens may pose a risk for children. These results suggest that there is cause for deeper concern about the safety of these foods and that effective countermeasures should be established to improve their microbiological safety.
Significance and Impact of the Study
Food safety is especially important for children, but only limited information is available about the microbiological quality of cheap and junk foods that are consumed frequently by primary schoolchildren (e.g. dried cakes, candies and chocolates). The present study investigated the microbial quality of cheap and junk foods, and our results indicate that these foods are a potential health risk for children, therefore, deeper concern about the safety of these foods and effective countermeasures should be established to improve their microbiological safety. The present study may contribute to the development of an appropriate child food safety management system. 相似文献143.
Dae Hwan Lee Ji Hyeon Ahn Joon Ha Park Bing Chun Yan Jeong-Hwi Cho In Hye Kim Jae-Chul Lee Sang-Hun Jang Myoung Hyo Lee In Koo Hwang Seung Myung Moon Bonghee Lee Jun Hwi Cho Hyung-Cheul Shin Jin Sang Kim Moo-Ho Won 《Cellular and molecular neurobiology》2013,33(5):615-624
Aging is an inevitable process that occurs in the whole body system accompanying with many functional and morphological changes. Inflammation is known as one of age-related factors, and inflammatory changes could enhance mortality risk. In this study, we compared immunoreactivities of inflammatory cytokines, such as interleukin (IL)-2 (a pro-inflammatory cytokine), its receptor (IL-2R), IL-4 (an anti-inflammatory cytokine), and its receptor (IL-4R) in the cervical and lumbar spinal cord of young adult (2–3 years old) and aged (10–12 years old) beagle dogs using immunohistochemistry and western blotting. IL-2 and IL-2R-immunoreactive nerve cells were found throughout the gray matter of the cervical and lumbar spinal cord of young adult and aged dogs. In the spinal cord neurons of the aged dog, immunoreactivity and protein levels were apparently increased compared with those in the young adult dog. Change patterns of IL-4- and IL-4R-immunoreactive cells and their protein levels were also similar to those in IL-2 and IL-2R; however, IL-4 and IL-4R immunoreactivity in the periphery of the neuronal cytoplasm in the aged dog was much stronger than that in the young adult dog. These results indicate that the increase of inflammatory cytokines and their receptors in the aged spinal cord might be related to maintaining a balance of inflammatory reaction in the spinal cord during normal aging. 相似文献
144.
Cutaneous mucormycosis is a rare opportunistic infection caused by zygomycetes that can be rapidly fatal if unrecognized. We describe the clinical, histopathological, fungal and molecular features of a case of gangrenous cutaneous mucormycosis. The patient presented with great necrosis on his right forearm at the site of detained intravenous cannula needle. He had type II diabetes and chronic renal insufficiency. KOH mount of black eschar showed many broad, aseptate fungal hyphae with right-angle branching. PAS staining of the tissue sample revealed similar broad hyphae in the dermis and cutis. Fungal culture and ITS sequence analysis identified this fungus as Rhizopus oryzae. As no organ involvement was detected, the patient was diagnosed with primary cutaneous mucormycosis. Considering the poor state of the patient, complete excision of the infectious tissue was performed without skin graft instead of amputation. At the same time, intravenous liposomal amphotericin B was given, starting from a small dosage and increased to a total dosage amount of 5.45 g. The wound recovered well with granulation. We emphasize that early recognition and prompt therapy including the control of the primary diseases were important. In this article, we also reviewed the features of primary cutaneous mucormycosis reported in China over the last 20 years. 相似文献
145.
We investigated a carbon nanoribbon (CNR) using atomistic simulations based on Tersoff–Brenner potential function. The CNR was obtained from a compressed (5,5) carbon nanotube (CNT). The obtained CNR had a cross-sectional view as a binocular telescope structure composed of both sp2 and sp3 bonds. One carbon atom per ten carbon atoms had sp3 bond. For the optimized structures, the residual forces on the CNR were 3-order higher than that on the CNR and the lattice constant of the CNR was higher 0.0624?Å than that of the CNT along the tube axis. The Young's modulus of the CNR was the same as that of the CNT whereas the critical strain of the CNR was significantly lower than that of the CNT because the residual stresses on the CNR was very higher than those on the CNT. The tensile force curve vs. the strain of the CNT was slightly higher than that of the CNR. 相似文献
146.
147.
Jeong Won Kang Young Gyu Choi Jun Ha Lee Oh Kuen Kwon Ho Jung Hwang 《Molecular simulation》2013,39(9):829-835
Pure carbon nanotube (CNT) oscillators are compared to the corresponding CNT oscillators encapsulating copper nanowires (Cu@CNTs) by molecular dynamics simulations. The classical oscillation theory provides a fairly good estimate of the mass dependence of the operating frequency when the CNT surface is not deformed by the Cu nanowire. The structural deformations of the CNT induced by the encapsulated copper nanowire have a greater effect on the oscillation frequency than the mass of the copper nanowire. The excess forces of the Cu@CNT oscillator are slightly higher than those of the CNT oscillator and the excess van der Waals forces induced by the inter-wall interactions are 17 times higher than the excess forces induced by the Cu nanowire–CNT interactions. 相似文献
148.
Deok-Soo Kim Chong-Min Kim Chung-In Won Jae-Kwan Kim Joonghyun Ryu Youngsong Cho 《Journal of biomolecular structure & dynamics》2013,31(1):219-242
Abstract This paper presents an approach and a software, BetaDock, to the docking problem by putting the priority on shape complementarity between a receptor and a ligand. The approach is based on the theory of the β-complex. Given the Voronoi diagram of the receptor whose topology is stored in the quasi-triangulation, the β-complex corresponding to water molecule is computed. Then, the boundary of the β-complex defines the β-shape which has the complete proximity information among all atoms on the receptor boundary. From the β-shape, we first compute pockets where the ligand may bind. Then, we quickly place the ligand within each pocket by solving the singular value decomposition problem and the assignment problem. Using the conformations of the ligands within the pockets as the initial solutions, we run the genetic algorithm to find the optimal solution for the docking problem. The performance of the proposed algorithm was verified through a benchmark test and showed that BetaDock is superior to a popular docking software AutoDock 4. 相似文献
149.
Hsuan-Liang Liu Chiao-Kai Hwang Jin-Chung Lin 《Journal of biomolecular structure & dynamics》2013,31(2):131-136
Abstract In this study, various 400 ps molecular dynamics simulations were conducted to determine the stabilizing effect of O-glycosylation on the secondary structural integrity of the design α-loop-α motif, which has the optimal loop length of 7 Gly residues (denoted as N-A16G7A16-C). In general, O-glycosylation stabilizes the structural integrity of the model peptide regardless of the length and position of glycosylation sites because it decreases the opportunity for water molecules to compete for the intramolecular hydrogen bonds. The designed peptide exhibits the highest helicity when residues 11 and 31 are replaced with Ser residues followed by O-linked with 3 galactose residues, representing the “face-to-face” glycosylation near the loop. In this case, the loop exhibits an extended conformation and several new hydrogen bonds are observed between the main chain of the loop and the galactose residues, resulting in decreasing the fluctuation and increasing the stability of the entire peptide. When the glycosylation are made close to the loop, the secondary structural integrity of the α-loop-α motif increases with the number of galactose residues. In addition, “face- to-face” glycosylation increases the structural integrity of this motif to a greater extent than “back-to-back” glycosylation. However, when the glycosylation are created away from the loop and near the N- and C-termini, no general rule is found for the stabilizing effect. 相似文献