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31.
H Matsumoto K Shibasaki M Uchigashima A Koizumi M Kurachi Y Moriwaki H Misawa K Kawashima M Watanabe S Kishi Y Ishizaki 《PloS one》2012,7(8):e42841
It has been long speculated that specific signals are transmitted from photoreceptors to the retinal pigment epithelium (RPE). However, such signals have not been identified. In this study, we examined the retinal expression and localization of acetylcholine-related molecules as putative candidates for these signals. Previous reports revealed that α7 nicotinic acetylcholine receptors (nAChRs) are present in the microvilli of RPE cells that envelope the tips of photoreceptor outer segments (OS). Secreted mammalian leukocyte antigen 6/urokinase-type plasminogen activator receptor-related protein-1 (SLURP-1) is a positive allosteric modulator of the α7 nAChR. Therefore, we first focused on the expression of SLURP-1. SLURP-1 mRNA was expressed in the outer nuclear layer, which is comprised of photoreceptor cell bodies. SLURP-1 immunoreactivity co-localized with rhodopsin and S-opsin in photoreceptor OS, while choline acetyltransferase (ChAT) and high affinity choline transporter (CHT-1) were also expressed in photoreceptor OS. Immunoelectron microscopy identified that the majority of SLURP-1 was localized to the plasma membranes of photoreceptor OS. These results provide evidence that SLURP-1 is synthesized in photoreceptor cell bodies and transported to photoreceptor OS, where SLURP-1 may also be secreted. Our findings suggest that photoreceptor OS communicate via neurotransmitters such as ACh and SLURP-1, while RPE cells might receive these signals through α7 nAChRs in their microvilli. 相似文献
32.
Satoru Fukiya Miki Arata Hiroko Kawashima Daisuke Yoshida Maki Kaneko Kimiko Minamida Jun Watanabe Yoshio Ogura Kiyohisa Uchida Kikuji Itoh Masaru Wada Susumu Ito & Atsushi Yokota 《FEMS microbiology letters》2009,293(2):263-270
Secondary bile acid-producing bacteria were isolated from human feces to improve our appreciation of the functional diversity and redundancy of the intestinal microbiota. In total, 619 bacterial colonies were isolated using a nutrient-poor agar medium and the level of secondary bile acid formation was examined in each by a liquid culture, followed by thin-layer chromatography. Of five strains analyzed by 16S rRNA gene sequencing and biochemical testing, one was identified as Bacteroides intestinalis AM-1, which was not previously recognized as a secondary bile-acid producer. GC-MS revealed that B. intestinalis AM-1 converts cholic acid (CA) and chenodeoxycholic acid into their 7-oxo derivatives, 7-oxo-deoxycholic acid (7-oxo-DCA) and 7-oxo-lithocholic acid, respectively. Thus, B. intestinalis AM-1 possesses 7α-hydroxysteroid dehydrogenase (7α-HSDH) activity. In liquid culture, B. intestinalis AM-1 showed a relatively higher productivity of 7-oxo-DCA than Escherichia coli HB101 and Bacteroides fragilis JCM11019T , which are known to possess 7α-HSDH activity. The level of 7α-HSDH activity was higher in B. intestinalis AM-1 than in the other two strains under the conditions tested. The 7α-HSDH activity in each of the three strains is not induced by CA; instead, it is regulated in a growth phase-dependent manner. 相似文献
33.
Murata Y Tsuruzoe K Kawashima J Furukawa N Kondo T Motoshima H Igata M Taketa K Sasaki K Kishikawa H Kahn CR Toyonaga T Araki E 《Biochemical and biophysical research communications》2007,364(2):301-307
Insulin receptor substrate-1 (IRS-1) is the major substrate of both the insulin receptor and the IGF-1 receptor. In this study, we created IRS-1 transgenic (IRS-1-Tg) mice which express human IRS-1 cDNA under control of the mouse IRS-1 gene promoter. In the IRS-1-Tg mice, IRS-1 mRNA expression was significantly increased in almost all tissues, but its protein expression was increased in very limited tissues (epididymal fat and skeletal muscle). IRS-1-Tg mice showed glucose intolerance and significantly enlarged epididymal fat mass, as well as elevated serum TNF-α concentrations. Importantly insulin signaling was significantly attenuated in the liver of IRS-1-Tg mice, which may contribute to the glucose intolerance. Our results suggest that excess IRS-1 expression may not provide a beneficial impact on glucose homeostasis in vivo. 相似文献
34.
The purpose of this study was to clarify the general architecture and morphological variations of the autonomic cardiac nervous system (ACNS) in the African Cercopithecidae (Old World monkeys), and to discuss the evolutionary changes between this system in African/Asian Cercopithecidae and humans. A detailed macroscopic comparative morphological investigation of the ACNS was performed by examining the left and right sides of 11 African cercopithecid specimens, including some previously unreported species (Abyssinian colobus, Angola pied colobus, Savanna monkey, and lesser white-nosed guenon). The common characteristics of the ACNS in the African Cercopithecidae are described in detail. Consequently, homologies of the ACNS between Asian (macaques) and African Cercopithecidae, and differences between the Asian/African Cercopithecidae and humans, were found. In particular, differences in the sympathetic (cardiac) systems of the Cercopithecidae and humans were recognized, despite the similar morphology of the parasympathetic vagal (cardiac) system. These differences include the composition of the cervicothoracic ganglion, the lower positions of the middle cervical and cervicothoracic ganglia, and the narrow range for the origin of the cardiac nerves in the Cercopithecidae, compared with that in humans. In conclusion, these findings are considered with regard to the morphology of the last common ancestors of the Cercopithecidae. 相似文献
35.
Tsujimoto H Hara K Tsukada Y Huang CC Kawashima Y Arakaki M Okayasu H Mimura H Miwa N 《Bioorganic & medicinal chemistry letters》2007,17(17):4771-4777
This paper describes the process of encapsulating hair growing ingredients in the PLGA nanospheres by emulsion solvent diffusion method and investigates the feasibility of using the PLGA nanospheres as the DDS (Drug delivery System) carriers for delivering various hair growing ingredients to hair follicles. In-vitro and in-vivo tests were conducted to verify the performances of encapsulated PLGA nanospheres with three different hair growing ingredients. In the in-vitro tests, the scalp-pore permeability of hair growing ingredient encapsulated PLGA nanospheres (dispersed in the PBS solution) was examined using human scalp biopsies in a modified Bronaugh diffusion chamber in comparison to that of the control samples containing the hair growing ingredient in the PBS solution. Furthermore, the hair growing effect of the encapsulated PLGA nanospheres was evaluated with the C3H mice in the in-vivo tests. By observing the fluorescence intensity of the ingredients, as shown in the cross-section photographs of the human scalp biopsies, it was found that the dispersion liquids containing hair growing ingredient encapsulated PLGA nanospheres exerted a scalp-pore permeability 2.0- to 2.5-fold more marked than that of the control samples. Also, the hair growing activities were enhanced by using the encapsulated PLGA nanospheres, which transformed the hair growth cycle from the resting phase to the growing phase. As a result, the degree of hair growth was improved significantly. These results suggested that the PLGA nanosphere can be a new DDS carrier for delivering hair growing ingredients and drugs to the hair follicles. 相似文献
36.
Ali HI Tomita K Akaho E Kambara H Miura S Hayakawa H Ashida N Kawashima Y Yamagishi T Ikeya H Yoneda F Nagamatsu T 《Bioorganic & medicinal chemistry》2007,15(1):242-256
Novel 2-deoxo-2-phenyl-5-deazaflavins and 2-deoxo-2-phenylflavin-5-oxides were prepared as a new class of antitumor agents and showed significant antitumor activities against NCI-H 460, HCT 116, A 431, CCRF-HSB-2, andKB cell lines. In vivo investigation, 2-deoxo-10-methyl-2-phenyl-5-deazaflavin exhibited the effective antitumor activity against A 431 human adenocarcinoma cells transplanted subcutaneously into nude mouse. Furthermore, AutoDock study has been done by binding of the flavin analogs into PTK pp60(c-src), where a good correlation between their IC(50) and AutoDock binding free energy was exhibited. In particular, 2-deoxo-2-phenylflavin-5-oxides exhibited the highest potential binding affinity within the binding pocket of PTK. 相似文献
37.
Naka T Sakoda T Doi T Tsujino T Masuyama T Kawashima S Iwasaki T Ohyanagi M 《Preparative biochemistry & biotechnology》2007,37(2):87-99
Viral vector systems are efficient for transfection of foreign genes into many tissues. Especially, retrovirus based vectors integrate the transgene into the genome of the target cells, which can sustain long term expression. However, it has been demonstrated that the transduction efficiency using retrovirus is relatively lower than those of other viruses. Ultrasound was recently reported to increase gene expression using plasmid DNA, with or without, a delivery vehicle. However, there are no reports, which show an ultrasound effect to retrovirus-mediated gene transfer efficiency. Retrovirus-mediated gene transfer systems were used for transfection of 293T cells, bovine aortic endothelial cells (BAECs), rat aortic smooth muscle cells (RASMCs), and rat skeletal muscle myoblasts (L6 cells) with beta-galactosidase (beta-Gal) genes. Transduction efficiency and cell viability assay were performed on 293T cells that were exposed to varying durations (5 to 30 seconds) and power levels (1.0 watts/cm(2) to 4.0 watts/cm(2)) of ultrasound after being transduced by a retrovirus. Effects of ultrasound to the retrovirus itself was evaluated by transduction efficiency of 293T cells. After exposure to varying power levels of ultrasound to a retrovirus for 5 seconds, 293T cells were transduced by a retrovirus, and transduction efficiency was evaluated. Below 1.0 watts/cm(2) and 5 seconds exposure, ultrasound showed increased transduction efficiency and no cytotoxicity to 293T cells transduced by a retrovirus. Also, ultrasound showed no toxicity to the virus itself at the same condition. Exposure of 5 seconds at the power of 1.0 watts/cm(2) of an ultrasound resulted in significant increases in retrovirus-mediated gene expression in all four cell types tested in this experiment. Transduction efficiencies by ultrasound were enhanced 6.6-fold, 4.8-fold, 2.3-fold, and 3.2-fold in 293T cells, BAECs, RASMCs, and L6 cells, respectively. Furthermore, beta-Gal activities were also increased by the retrovirus with ultrasound exposure in these cells. Adjunctive ultrasound exposure was associated with enhanced retrovirus-mediated transgene expression in vitro. Ultrasound associated local gene therapy has potential for not only plasmid-DNA-, but also retrovirus-mediated gene transfer. 相似文献
38.
Harimoto T Takei K Kawano T Ishihara A Kawashima T Kaneko H Ishida M Usui S 《Biosensors & bioelectronics》2011,26(5):2368-2375
In order to record multi-site electroretinogram (ERG) responses in isolated carp retinae, we utilized three-dimensional (3D), extracellular, 3.5-μm-diameter silicon (Si) probe arrays fabricated by the selective vapor-liquid-solid (VLS) growth method. Neural recordings with the Si microprobe exhibit low signal-to-noise (S/N) ratios of recorded responses due to the high-electrical-impedance characteristics of the small recording area at the probe tip. To increase the S/N ratio, we designed and fabricated enlarged gold (Au) tipped Si microprobes (10-μm-diameter Au tip and 3.5-μm-diameter probe body). In addition, we demonstrated that the signal attenuation and phase delay of ERG responses recorded via the Si probe can be compensated by the inverse filtering method. We conclude that the reduction of probe impedance and the compensation of recorded signals are useful approaches to obtain distortion-free recording of neural signals with high-impedance microelectrodes. 相似文献
39.
Masahiro Ono Rumi Watanabe Hidekazu Kawashima Tomoki Kawai Hiroyuki Watanabe Mamoru Haratake Hideo Saji Morio Nakayama 《Bioorganic & medicinal chemistry》2009,17(5):2069-2076
In vivo imaging of β-amyloid (Aβ) aggregates in the brain may lead to early detection of Alzheimer’s disease (AD) and monitoring of the progression and effectiveness of treatment. The purpose of this study was to develop novel 18F-labeled amyloid-imaging probes based on flavones as a core structure. Fluoropegylated (FPEG) flavone derivatives were designed and synthesized. The affinity of the derivatives for Aβ aggregates varied from 5 to 321 nM. In brain sections of AD model mice, FPEG flavones with the dimethylamino group intensely stained β-amyloid plaques. In biodistrubution experiments using normal mice, they displayed high uptake in the brain ranging from 2.9 to 4.2%ID/g at 2 min postinjection. The radioactivity washed out from the brain rapidly (1.3–2.0%ID/g at 30 min), which is highly desirable for β-amyloid imaging agents. FPEG flavones may be potential PET imaging agents for β-amyloid plaques in Alzheimer’s brains. 相似文献
40.