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981.
Junichi Sugenoya Tokuo Ogawa Kazuno Jmai Norikazu Ohnishi Keiko Natsume 《European journal of applied physiology and occupational physiology》1995,71(1):33-40
To examine whether cutaneous active vasodilatation is mediated by sudomotor nerve fibres we recorded cutaneous blood flow and sweat rates continuously with laser-Doppler flowmetry and capacitance hygrometry, respectively, from the dorsal and plantar aspects of the foot in 11 male subjects at varying ambient temperatures (T
a) between 22 and 40°C (relative humidity 40%). In a warmer environment (T
a 29–40°C), predominant responses of the blood flow curve from the sole of the foot were transient depressions (negative blood flow responses, NBR), whereas those from the dorsal foot were transient increases (positive blood flow responses, PBR). The PBR on the dorsal foot occurred spontaneously or in response to mental or sensory stimuli, and when PBR did not fuse with each other the rate of PBR was linearly related to tympanic temperature. When dorsal foot sweating was continuous, PBR on the dorsal foot almost entirely synchronized with sweat expulsion. When dorsal foot sweating was intermittent PBR sometimes occurred on the dorsal foot without corresponding sweat expulsions, but these PBR showed a complete correspondence with subthreshold sweat expulsion seen on a methacholine-treated area. The amplitude and the duration of PBR showed a significant linear relationship with the amplitude and the duration of the corresponding sweat expulsion. In a thermoneutral or cooler environment (T
a 22–29°C), PBR occurred on the sole of the foot when mental or sensory stimuli elicited sweating in that area. Thus, PBR occurred when and where sweating appeared. Atropine failed to abolish PBR on the dorsal foot. Blockade of the peroneal nerve eliminated both PBR and NBR on the dorsal foot. The results indicate that an active vasodilatation mechanism is present on the sole of the foot as well as on the dorsal foot, and thus suggest that active vasodilatation is closely related to sudomotor nerve activation. 相似文献
982.
983.
Takeshi Sasaki Junichi Imanishi Keiko Ioki Youngkeun Song Yukihiro Morimoto 《Landscape and Ecological Engineering》2016,12(1):117-127
In this study, we evaluated methods for reliably estimating leaf area index (LAI) and gap fraction in two different types of broad-leaved forests by the use of airborne light detection and ranging (LiDAR) data. We evaluated 13 estimation variables related to laser height, laser penetration rate, and laser point attributes that were derived from LiDAR analyses. The relationships between LiDAR-derived estimates and field-based measurements taken from the forests were evaluated with simple linear regressions. The data from the two forests were analyzed separately and as an integrated dataset. Among the laser height variables, the coefficient of variation (CV) of all laser point heights had the highest level of accuracy for estimating both LAI and gap fraction. However, we recommend that more evaluations be conducted prior to the use of CV in forests with complex structures. The simplest laser penetration variable, which represents the ratio of the number of ground points to the total number of all points (P ALL), also had a high level of accuracy for estimating LAI and gap fraction at the study sites regardless of whether the data were analyzed separately or as an integrated data set. Furthermore, P ALL values showed near 1:1 relationships with the field-based gap fraction values. Hence, the use of P ALL may be the most practical for estimating LAI and gap fraction in broad-leaved forests, even when the canopies are heavily closed. 相似文献
984.
Haruo Shimizu Yoshiaki Arimura Kei Onodera Hiroaki Takahashi Satoshi Okahara Junichi Kodaira Hirokazu Oohashi Hiroyuki Isshiki Kentaro Kawakami Kentaro Yamashita Yasuhisa Shinomura Masao Hosokawa 《PloS one》2016,11(2)
Background
Parameters reported in pathologic reviews have been failing to assess exactly the malignant potential of gastrointestinal cancers. We hypothesized that malignant potential could be defined by common latent variables (hypothesis I), but there are substantial differences in the associations between malignant potential and pathologic parameters according to the origin of gastrointestinal cancers (hypothesis II). We shed light on these issues by structural equation modeling.Materials and Methods
We conducted a cross-sectional survey of 217 esophageal, 192 gastric, and 175 colorectal cancer patients who consecutively underwent curative surgery for their pathologic stage I cancers at Keiyukai Sapporo Hospital. Latent variables identified by factor analysis and seven conventional pathologic parameters were introduced in the structural equation modeling analysis.Results
Because latent variables were disparate except for their number, ''three'' in the examined gastrointestinal cancers, the first hypothesis was rejected. Because configural invariance across gastrointestinal cancers was not approved, the second hypothesis was verified. We could trace the three significant paths on the causal graph from latent variables to lymph node metastasis, which were mediated through depth, lymphatic invasion, and matrilysin expression in esophageal cancer, whereas only one significant path could be traced in both gastric and colorectal cancer. Two of the three latent variables were exogenous in esophageal cancer, whereas one factor was exogenous in the other gastrointestinal cancers. Cancer stemness promoted viability in esophageal cancer, but it was suppressed in others.Conclusion
These results reflect the malignant potential of esophageal cancer is higher than that of the other gastrointestinal cancers. Such information might contribute to refining clinical treatments for gastrointestinal cancers. 相似文献985.
Growth and development, and auxin polar transport in Arabidopsis thaliana transformed with iaaH gene were studied under simulated microgravity conditions on a three-dimensional (3-D) clinostat. Simulated microgravity conditions on a 3-D clinostat did not affect the number of rosette leaves but promoted the growth and development (fresh weight of plant and the elongation of flower stalk) of transformants. Final growth of transformants under simulated microgravity conditions on a 3-D clinostat was almost equivalent to that grown on 1 g conditions in the presence of 1 micromoles IAM (indole-3-acetamide). The activities of auxin polar transport in the segments of flower stalk (inflorescence axis) of transformants grown on 1 g conditions were significantly promoted by the addition of IAM. Interestingly, simulated microgravity conditions on a 3-D clinostat also promoted the activities of auxin polar transport of transformants grown on the medium with or without IAM. Based on the results in this study, transgenic plants may not have an efficient homeostatic mechanism for the control of growth and development, and auxin polar transport activity in microgravity conditions in space. 相似文献
986.
Iwamoto S Motomura K Shinoda Y Urata M Kato J Takiguchi N Ohtake H Hirota R Kuroda A 《Applied and environmental microbiology》2007,73(17):5676-5678
Heat-treated Escherichia coli producing Thermus polyphosphate kinase regenerated ATP by using exogenous polyphosphate. This recombinant could be used as a platform to produce valuable compounds in combination with thermostable phosphorylating or energy-requiring enzymes. In this work, we demonstrated the production of fructose 1,6-diphosphate from fructose and polyphosphate. 相似文献
987.
Shiba Y Masuda H Watanabe N Ego T Takagaki K Ishiyama K Ohgi T Yano J 《Nucleic acids research》2007,35(10):3287-3296
A long RNA oligomer, a 110mer with the sequence of a precursor-microRNA candidate, has been chemically synthesized in a single synthesizer run by means of standard automated phosphoramidite chemistry. The synthetic method involved the use of 2-cyanoethoxymethyl (CEM), a 2′-hydroxyl protecting group recently developed in our laboratory. We improved the methodology, introducing better coupling and capping conditions. The overall isolated yield of highly pure 110mer was 5.5%. Such a yield on a 1-μmol scale corresponds to 1mg of product and emphasizes the practicality of the CEM method for synthesizing oligomers of more than 100nt in sufficient quantity for biological research. We confirmed the identity of the 110mer by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry, as well as HPLC, electrophoretic methods, and RNase-digestion experiments. The 110mer also showed sense-selective specific gene-silencing activity. As far as we know, this is the longest chemically synthesized RNA oligomer reported to date. Furthermore, the identity of the 110mer was confirmed by both physicochemical and biological methods. 相似文献
988.
START-GAP3/DLC3 is a GAP for RhoA and Cdc42 and is localized in focal adhesions regulating cell morphology 总被引:2,自引:0,他引:2
Kawai K Kiyota M Seike J Deki Y Yagisawa H 《Biochemical and biophysical research communications》2007,364(4):783-789
In the human genome there are three genes encoding RhoGAPs that contain the START (steroidogenic acute regulatory protein (StAR)-related lipid transfer)—domain. START-GAP3/DLC3 is a tumor suppressor gene similar to two other human START-GAPs known as DLC1 or DLC2. Although expression of START-GAP3/DLC3 inhibits the proliferation of cancer cells, its molecular function is not well understood. In this study we carried out biochemical characterization of START-GAP3/DLC3, and explored the effects of its expression on cell morphology and intracellular localization. We found that START-GAP3/DLC3 serves as a stimulator of PLCδ1 and as a GAP for both RhoA and Cdc42 in vitro. Moreover, we found that the GAP activity is responsible for morphological changes. The intracellular localization of endogenous START-GAP3/DLC3 was explored by immunocytochemistry and was revealed in focal adhesions. These results indicate that START-GAP3/DLC3 has characteristics similar to other START-GAPs and the START-GAP family seems to share common characteristics. 相似文献
989.
Shinohara H Horiuchi M Sato M Kurisaki J Kusakabe T Koga K Minami Y Aoki T Kato I Sugimoto Y 《Biochimica et biophysica acta》2007,1770(1):5-11
Ovalbumin is a serpin without inhibitory activity against proteases. During embryonic development, ovalbumin in the native (N) form undergoes changes and takes a heat-stable form, which was previously named HS-ovalbumin. It has been known that N-ovalbumin is artificially converted to another thermostable form called S-ovalbumin by heating at an alkaline pH. Here, we characterized further the three ovalbumin forms, N, HS, and S. The epitope of the monoclonal antibody 2B3/2H11, which recognizes N- and HS-ovalbumin but not S-ovalbumin, was found to reside in the region Glu-Val-Val-Gly-Ala-Ser-Glu-Ala-Gly-Val-Asp-Ala-Ala-Ser-Val-Ser-Glu-Glu-Phe-Arg, which corresponds to 340-359 of amino acid residues and is contained in the reactive center loop (RCL). Removal of RCL by elastase or subtilisin mitigated binding of the antibody. Dephosphorylation experiments indicated that the phosphorylated Ser-344 residue located on RCL is crucial for the epitope recognition. We suggest that the shift to the heat-stable form of ovalbumin accompanies a movement of RCL. 相似文献
990.