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991.
Masae I. Ishihara Satoshi N. Suzuki Masahiro Nakamura Tsutomu Enoki Akio Fujiwara Tsutom Hiura Kosuke Homma Daisuke Hoshino Kazuhiko Hoshizaki Hideyuki Ida Ken Ishida Akira Itoh Takayuki Kaneko Kaname Kubota Koichiro Kuraji Shigeo Kuramoto Akifumi Makita Takashi Masaki Kanji Namikawa Kaoru Niiyama Mahoko Noguchi Haruto Nomiya Tatsuhiro Ohkubo Satoshi Saito Takeshi Sakai Michinori Sakimoto Hitoshi Sakio Hirofumi Shibano Hisashi Sugita Mitsuo Suzuki Atsushi Takashima Nobuyuki Tanaka Naoaki Tashiro Naoko Tokuchi Toshiya Yoshida Yumiko Yoshida 《Ecological Research》2011,26(6):1007-1008
This data paper reports tree census data collected in a network of 34 forest sites in Japan. This is the largest forest data set freely available in Japan to date. The network is a part of the Monitoring Sites 1000 Project launched by the Ministry of the Environment, Japan. It covers subarctic to subtropical climate zones and the four major forest types in Japan. Forty-two permanent plots, usually 1?ha in size, were established in old-growth or secondary natural forests. Censuses of woody species ??15?cm girth at breast height were conducted every year or once during 2004 to 2009. The data provide species abundance, survivorship and stem girth growth of 52,534 individuals of 334 tree and liana species. The censuses adopted common census protocol, which provide good opportunities for meta-analyses and comparative studies among forests. The data have been used for ecological studies as well as for the biodiversity reports published by the Ministry of the Environment. 相似文献
992.
Tomohiro Doi Hideyuki Kajihara Yasuo Chuman Shinobu Kuwae Takashi Kaminagayoshi Takeshi Omasa 《Biotechnology progress》2020,36(5):e3000
Herein, we described a scale-up strategy focused on the dissolved carbon dioxide concentration (dCO2) during fed-batch cultivation of Chinese hamster ovary cells. A fed-batch culture process for a 2000-L scale stainless steel (SS) bioreactor was scaled-up from similarly shaped 200-L scale bioreactors based on power input per unit volume (P/V). However, during the 2000-L fed-batch culture, the dCO2 was higher compared with the 200-L scale bioreactor. Therefore, we developed an alternative approach by evaluating the kLa values of O2 (kLa[O2]) and CO2 [kLa(CO2)] in the SS bioreactors as a scale-up factor for dCO2 reduction. The kLa ratios [kLa(CO2)/kLa(O2)] were different between the 200-L and 2000-L bioreactors under the same P/V condition. When the agitation conditions were changed, the kLa ratio of the 2000-L scale bioreactor became similar and the P/V value become smaller compared with those of the 200-L SS bioreactor. The dCO2 trends in fed-batch cultures performed in 2000-L scale bioreactors under the modified agitation conditions were similar to the control. This kLa ratio method was used for process development in single-use bioreactors (SUBs) with shapes different from those of the SS bioreactor. The kLa ratios for the SUBs were evaluated and conditions that provided kLa ratios similar to the 200-L scale SS bioreactors were determined. The cell culture performance and product quality at the end of the cultivation process were comparable for all tested SUBs. Therefore, we concluded that the kLa ratio is a powerful scale-up factor useful to control dCO2 during fed-batch cultures. 相似文献
993.
Light-oxygen-voltage (LOV) domains function as blue light-inducible molecular switches. The photosensory LOV domains derived from plants and fungi have provided an indispensable tool for optogenetics. Here we develop a high-throughput screening system to efficiently improve switch-off kinetics of LOV domains. The present system is based on fluorescence imaging of thermal reversion of a flavin cofactor bound to LOV domains. We conducted multi site-directed random mutagenesis of seven amino acid residues surrounding the flavin cofactor of the second LOV domain derived from Avena sativa phototropin 1 (AsLOV2). The gene library was introduced into Escherichia coli cells. Then thermal reversion of AsLOV2 variants, respectively expressed in different bacterial colonies on agar plate, was imaged with a stereoscopic fluorescence microscope. Based on the mutagenesis and imaging-based screening, we isolated 12 different variants showing substantially faster thermal reversion kinetics than wild-type AsLOV2. Among them, AsLOV2-V416T exhibited thermal reversion with a time constant of 2.6 s, 21-fold faster than wild-type AsLOV2. With a slight modification of the present approach, we also have efficiently isolated 8 different decelerated variants, represented by AsLOV2-V416L that exhibited thermal reversion with a time constant of 4.3×103 s (78-fold slower than wild-type AsLOV2). The present approach based on fluorescence imaging of the thermal reversion of the flavin cofactor is generally applicable to a variety of blue light-inducible molecular switches and may provide a new opportunity for the development of molecular tools for emerging optogenetics. 相似文献
994.
Zhang Ze; Luo Z. W.; Kishino Hirohisa; Kearsey Mike J. 《Molecular biology and evolution》2005,22(4):1156
doi:10.1093/molbev/msi034 Mol. Biol. 相似文献
995.
996.
Tsukasa Takahashi Kisaburo Hanazawa Takashi Inoue Kenya Sato Ayako Sedohara Junko Okahara Hiroshi Suemizu Chie Yagihashi Masafumi Yamamoto Tomoo Eto Yusuke Konno Hideyuki Okano Makoto Suematsu Erika Sasaki 《PloS one》2014,9(4)
Intracytoplasmic sperm injection (ICSI), an important method used to treat male subfertility, is applied in the transgenic technology of sperm-mediated gene transfer. However, no study has described successful generation of offspring using ICSI in the common marmoset, a small non-human primate used as a model for biomedical translational research. In this study, we investigated blastocyst development and the subsequent live offspring stages of marmoset oocytes matured in vitro and fertilized by ICSI. To investigate the optimal timing of performing ICSI, corrected immature oocytes were matured in vitro and ICSI was performed at various time points (1–2 h, 2–4 h, 4–6 h, 6–8 h, and 8–10 h after extrusion of the first polar body (PB)). Matured oocytes were then divided randomly into two groups: one was used for in vitro fertilization (IVF) and the other for ICSI. To investigate in vivo development of embryos followed by ICSI, 6-cell- to 8-cell-stage embryos and blastocysts were nonsurgically transferred into recipient marmosets. Although no significant differences were observed in the fertilization rate of blastocysts among ICSI timing after the first PB extrusion, the blastocyst rate at 1–2 h was lowest among groups at 2–4 h, 4–6 h, 6–8 h, and 8–10 h. Comparing ICSI to IVF, the fertilization rates obtained in ICSI were higher than in IVF (p>0.05). No significant difference was noted in the cleaved blastocyst rate between ICSI and IVF. Following the transfer of 37 ICSI blastocysts, 4 of 20 recipients became pregnant, while with the transfer of 21 6-cell- to 8-cell-stage ICSI embryos, 3 of 8 recipients became pregnant. Four healthy offspring were produced and grew normally. These are the first marmoset offspring produced by ICSI, making it an effective fertilization method for marmosets. 相似文献
997.
Takeshi Ishikawa Satoshi Kokura Tatsuji Enoki Naoyuki Sakamoto Tetsuya Okayama Mitsuko Ideno Junichi Mineno Kazuko Uno Naohisa Yoshida Kazuhiro Kamada Kazuhiro Katada Kazuhiko Uchiyama Osamu Handa Tomohisa Takagi Hideyuki Konishi Nobuaki Yagi Yuji Naito Yoshito Itoh Toshikazu Yoshikawa 《PloS one》2014,9(1)
Background
Previous studies have demonstrated that less-differentiated T cells are ideal for adoptive T cell transfer therapy (ACT) and that fibronectin CH296 (FN-CH296) together with anti-CD3 resulted in cultured cells that contain higher amounts of less-differentiated T cells. In this phase I clinical trial, we build on these prior results by assessing the safety and efficacy of FN-CH296 stimulated T cell therapy in patients with advanced cancer.Methods
Patients underwent fibronectin CH296-stimulated T cell therapy up to six times every two weeks and the safety and antitumor activity of the ACT were assessed. In order to determine immune function, whole blood cytokine levels and the number of peripheral regulatory T cells were analyzed prior to ACT and during the follow up.Results
Transferred cells contained numerous less-differentiated T cells greatly represented by CD27+CD45RA+ or CD28+CD45RA+ cell, which accounted for approximately 65% and 70% of the total, respectively. No ACT related severe or unexpected toxicities were observed. The response rate among patients was 22.2% and the disease control rate was 66.7%.Conclusions
The results obtained in this phase I trial, indicate that FN-CH296 stimulated T cell therapy was very well tolerated with a level of efficacy that is quite promising. We also surmise that expanding T cell using CH296 is a method that can be applied to other T- cell-based therapies.Trial Registration
UMIN UMIN000001835 相似文献998.
Yukiko Doi Hideyuki Takeuchi Hiroyuki Mizoguchi Kazuya Fukumoto Hiroshi Horiuchi Shijie Jin Jun Kawanokuchi Bijay Parajuli Yoshifumi Sonobe Tetsuya Mizuno Akio Suzumura 《PloS one》2014,9(7)
Soluble oligomeric amyloid β (oAβ) causes synaptic dysfunction and neuronal cell death, which are involved in the pathogenesis of Alzheimer''s disease (AD). The hematopoietic growth factor granulocyte-colony stimulating factor (G-CSF) is expressed in the central nervous system (CNS) and drives neurogenesis. Here we show that G-CSF attenuated oAβ neurotoxicity through the enhancement of the enzymatic activity of Aβ-degrading enzyme neprilysin (NEP) in neurons, while the NEP inhibitor thiorphan abolished the neuroprotection. Inhibition of MEK5/ERK5, a major downstream effector of G-CSF signaling, also ablated neuroprotective effect of G-CSF. Furthermore, intracerebroventricular administration of G-CSF enhanced NEP enzymatic activity and clearance of Aβ in APP/PS1 transgenic mice. Thus, we propose that G-CSF may be a possible therapeutic strategy against AD. 相似文献
999.
Interleukin-1β Induces Blood–Brain Barrier Disruption by Downregulating Sonic Hedgehog in Astrocytes
Yue Wang Shijie Jin Yoshifumi Sonobe Yi Cheng Hiroshi Horiuchi Bijay Parajuli Jun Kawanokuchi Tetsuya Mizuno Hideyuki Takeuchi Akio Suzumura 《PloS one》2014,9(10)
The blood–brain barrier (BBB) is composed of capillary endothelial cells, pericytes, and perivascular astrocytes, which regulate central nervous system homeostasis. Sonic hedgehog (SHH) released from astrocytes plays an important role in the maintenance of BBB integrity. BBB disruption and microglial activation are common pathological features of various neurologic diseases such as multiple sclerosis, Parkinson’s disease, amyotrophic lateral sclerosis, and Alzheimer’s disease. Interleukin-1β (IL-1β), a major pro-inflammatory cytokine released from activated microglia, increases BBB permeability. Here we show that IL-1β abolishes the protective effect of astrocytes on BBB integrity by suppressing astrocytic SHH production. Astrocyte conditioned media, SHH, or SHH signal agonist strengthened BBB integrity by upregulating tight junction proteins, whereas SHH signal inhibitor abrogated these effects. Moreover, IL-1β increased astrocytic production of pro-inflammatory chemokines such as CCL2, CCL20, and CXCL2, which induce immune cell migration and exacerbate BBB disruption and neuroinflammation. Our findings suggest that astrocytic SHH is a potential therapeutic target that could be used to restore disrupted BBB in patients with neurologic diseases. 相似文献
1000.
Masahiro Ishikawa Hiromu Ito Toshiyuki Kitaori Koichi Murata Hideyuki Shibuya Moritoshi Furu Hiroyuki Yoshitomi Takayuki Fujii Koji Yamamoto Shuichi Matsuda 《PloS one》2014,9(8)