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31.
Tetsuya Matsumoto Mitsuo Kaku Kazuhiro Tateda Nobuhiko Furuya Yoichi Hirakata Keizo Yamaguchi 《Microbiology and immunology》1994,38(4):287-293
We evaluated antibody-coated bacteria (ACB) in expectorated sputum to discriminate contaminating or colonizing organisms from true pathogens. We examined 60 expectorated sputum samples from 51 patients with lower respiratory infections (chronic obstructive pulmonary disease 25, pneumonia 20, purulent tracheobronchitis 6). All samples were examined with quantitative culture and immunofluorescent demonstration of ACB. From the results of quantitative culture, we divided specimens into pathogen-isolated and pathogen-free samples. Among pathogen-isolated samples, in which we isolated accepted pathogenic organisms at ≥ 107 colony-forming units per ml, 16 of 23 samples were ACB-positive (69.5%). In contrast, among pathogen-free samples, in which we isolated accepted pathogens at < 107 colony forming units per ml or only upper respiratory flora, only 3 of 37 samples were ACB-positive (8.1%). The ACB-positive rate was significantly higher in pathogen-isolated than in pathogen-free samples (P < 0.001). Consequently, detecting ACB in expectorated sputum shows good potential as another criterion for distinguishing contaminating or colonizing organisms from true pathogens. 相似文献
32.
Kimura Tetsuya; Takeda Shin; Kyozuka Junko; Asahi Tadashi; Shimamoto Ko; Nakamura Kenzo 《Plant & cell physiology》1993,34(2):345-355
A precursor to the 相似文献
33.
Tetsuya Oguma Asahi Matsuyama Mamoru Kikuchi Eiichi Nakano 《Applied microbiology and biotechnology》1993,39(2):197-203
The gene for cyclomaltodextrinase (CDase; EC 3.2.1.54) from Bacillus sphaericus E-244 was cloned in the recombinant plasmid pCD629. Sequencing a portion of pCD629 revealed a unique open reading frame of 1,773 nucleotides coding for a 591-amino-acid polypeptide. The deduced polypeptide sequence showed about 50% homology with that of a neopullulanase, and was slightly homologous to those of the cyclodextrin glucanotransferases and the -amylases. The optimum pH, specific activity and K
m value for -cyclodextrin of the CDase that has been produced in Escherichia coli cells were 8.0, 16.4 units/mg protein, and 0.41 mm, respectively. These values were almost identical to those from B. sphaericus E-244.
Correspondence to: T. Oguma 相似文献
34.
35.
Nobuko Naito Evelyn Grace De Jesus Yasumitsu Nakai Tetsuya Hirano 《Cell and tissue research》1993,272(3):429-437
Tissue non-specific alkaline phosphatase is a membrane-bound glycoprotein enzyme which is characterized by its phosphohydrolytic, protein phosphatase, and phosphotransferase activities. This enzyme is distributed virtually in all mammalian tissues, particularly during embryonic development. Its expression is stagespecific and can be demonstrated in the developing embryo as early as the 2-cell stage. It has been suggested that tissue non-specific alkaline phosphatase might play a role in tissue formation. In the study reported here, a genetransfer approach was employed to investigate possible roles for this enzyme by inserting the cDNA for rat tissue non-specific alkaline phosphatase into CHO and LLC-PK1 cells. Permanently transfected cell-lines expressing varying levels of alkaline phosphatase were estblished. The data showed that functional enzyme was expressed in the transfected cells. Cell spreading and attachment were enhanced in transfected CHO cells expressing high levels of tissue non-specific alkaline phosphatase but not in the LLC-PK1 cells. Further, in CHO cells, proliferation was shown to be inversely proportional to the level of the tissue non-specific alkaline phosphatase expression. Homotypic cell association was demonstrated in both alkaline phosphatase-positive and alkaline phosphatase-negative cells in both CHO and LLC-PK1 celllines. Taken together, these findings suggest that in addition to a role in mineralization of bone, tissue nonspecific alkaline phosphatase might also play a role in other cell activities, including those related to differentiation, such as cell-cell or cell-substrate interaction and proliferation. 相似文献
36.
37.
Noritsugu Yabe Kouji Komiya Tetsuya Takezono Hisao Matsui 《In vitro cellular & developmental biology. Animal》1993,29(10):795-806
Summary Lysozyme at 1 to 100μg/ml of exposure levels augmented or inhibited proliferative response of human peripheral blood lymphocytes stimulated with
interleukin-2 (IL-2). This contradictory effect of lysozyme depended on IL-2 concentration, activating state of lymphocytes,
addition time of lysozyme, and serum existence. Lymphocytes increased their IL-2-mediated proliferating ability in response
to lysozyme when stimulated with less than suboptimal concentration of IL-2. Lymphocyte activation with anti-CD3 antibody
changed the augmented proliferative response into the inhibited response by lysozyme addition whereas elimination of MHC class
II molecule-expressing cells augmented the response. Addition of lysozyme within 1 h after IL-2 exposure was most effective
in promoting the proliferation whereas additions after 16 to 24 h were ineffective or inhibitory. Addition after longer than
24 h inversely restored the proliferative response. Serum seemed to retard lysozyme action because either sequential serum
addition 1 h after exposure of IL-2 and lysozyme to cells or exposure of IL-2 and serum after pretreatment of cells with lysozyme
changed the proliferative responsiveness from inhibition into augmentation. Thus lysozyme may regulate lymphocyte proliferation
responding to a magnitude of antigenic stimuli and to the progression of cellular events that periodically occur. 相似文献
38.
Tetsuya Kimura Taku Hamada Linda Massako Ueno Toshio Moritani 《Journal of electromyography and kinesiology》2003,13(5):433-440
The present study examined, whether or not mechanomyogram (MMG) amplitude and frequency component could reflect the contractile properties of the triceps surae muscles, composed of relatively slow soleus (SOL) and fast medial gastrocnemius (MG), during experimentally induced hypothermia condition. In eight male subjects, lying in prone position, supramaximal single twitch and repetitive electrical stimulations at 10 Hz were applied at the intramuscular temperatures of control (34 degrees C), 15, 20, and 25 degrees C, respectively. The hypothermia induced substantial reduction in muscle contractile properties, e.g. prolonged twitch contraction and half relaxation times, resulted in a highly significant reduction in the fluctuation of force signal during the repetitive stimulations. These changes were almost mirrored by the similar and significant reductions in the MMG amplitude in both SOL and MG. Power spectrum analysis revealed that peak frequency components of MMG and fluctuation of force were almost matched with the applied stimulation frequencies, independent of the temperature condition. These results strongly suggest that MMG analysis could be employed to study muscle contractile properties varying across different physiological conditions. 相似文献
39.
Myonsun Yoh Guang-Qing Tang Tetsuya Iida Naoko Morinaga Masatoshi Noda Takeshi Honda 《The international journal of biochemistry & cell biology》1996,28(12):1365-1369
Thermostable direct hemolysin (TDH) is a possible virulence factor produced by Vibrio parahaemolyticus. Although TDH has a variety of biological activities, including hemolytic activity, the biochemical mechanism of action remains uncertain. Here we analysed biochemical events, especially phosphorylation, caused by TDH in erythrocytes, and found that TDH caused significant phosphorylations of proteins on erythrocyte membrane. Phosphorylation of proteins was studied using γ-32P ATP and SDS-PAGE. A number of protein kinase inhibitors were tested, to determine which types of kinases were involved in the phosphorylation events. TDH induced the phosphorylation of two proteins on membranes of human erythrocyte that are sensitive to TDH. The estimated molecular weight of these proteins was 25 and 22.5 kDa. Interestingly, the 22.5 kDa, but not the 25 kDa protein, was phosphorylated on the membrane of TDH-insensitive (resistant) horse erythrocytes. Moreover, a mutant TDH (R7), which retained binding ability but lost hemolytic activity, also phosphorylated only the 22.5 kDa protein on human erythrocyte membranes. Among the protein kinase inhibitors used the protein kinase C inhibitors, (staurosporine and calphostin C) showed marked inhibition of phosphorylation of 25 kDa protein. In addition to phosphorylation, these protein kinase C inhibitors suppresssed hemolysis by TDH. These results indicate that the phosphorylation of the 25 kDa protein seems to be essential for the hemolysis by TDH after it binds to erythrocyte membranes. 相似文献
40.
Tetsuya Tanigawa Yasuo Mizo-oku Kouichi Moriguchi Takashi Suzuki Takahiko Osumi Masaaki Odomi 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1996,683(2):135
A simple and rapid quantitative method for 13C-labelled urea ([13C]urea) in human serum was developed by using high-performance liquid chromatography-atmospheric pressure chemical ionization mass spectrometry (HPLC-APCI-MS). This method is used to establish and normalize the [13C]urea breath test, which is considered as an effective diagnostic method for Helicobacter pylori infection. HPLC-APCI-MS, involving a simple pretreatment process such as diluting serum with water, was shown to be able to discriminate the extrinsic [13C]urea from intrinsic urea present at high concentration in serum. In addition, a 13C nuclear magnetic resonance spectroscopic quantitative method for [13C]urea in human urine is also described. The precision and accuracy of measured concentrations in these two methods were found to be within the acceptable limit. An application of these methods to investigate the pharmacokinetic profile of orally administered [13C]urea in human serum and urine is also presented. 相似文献