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941.
Miyashita M Ito N Ikeda S Murayama T Oguma K Kimura J 《Biosensors & bioelectronics》2009,24(5):1336-1340
The highly sensitive urine glucose meter based on amperometric glucose sensor was developed and commercialized. It shows remarkable performances of wide measurement range in 0-2000 mgdl(-1), rapid response time as 6s and robustness against influence by interferents like ascorbic acid or acetaminophen. Correlation between the developed urine glucose meter and commercialized clinical-use urine glucose analyzer showed excellent linear relationship. The monitoring of postmeal blood glucose levels by assess of urine glucose of actual subjects was performed with the developed urine glucose meter. The experimental results suggest the urine glucose level 120 min following the meal should be the appropriate index for diabetes or impaired glucose tolerance to control blood glucose level. The new portable meter was developed, and is expected for flexible use at places other than home or office. 相似文献
942.
943.
Shinjirou Kawazoe Nobuhito Ikeda Kengo Miki Masayuki Shibuya Kumi Morikawa Seiji Nakano Mitsuo Oshimura Ichiro Hisatome Yasuaki Shirayoshi 《Development, growth & differentiation》2009,51(2):81-93
Embryonic carcinoma (EC) cells, which are malignant stem cells of teratocarcinoma, have numerous morphological and biochemical properties in common with pluripotent stem cells such as embryonic stem (ES) cells. However, three EC cell lines (F9, P19 and PCC3) show different developmental potential and self‐renewal capacity from those of ES cells. All three EC cell lines maintain self‐renewal capacity in serum containing medium without Leukemia Inhibitory factor (LIF) or feeder layer, and show limited differentiation capacity into restricted lineage and cell types. To reveal the underlying mechanism of these characteristics, we took the approach of characterizing extrinsic factors derived from EC cells on the self‐renewal capacity and pluripotency of mouse ES cells. Here we demonstrate that EC cell lines F9 and P19 produce factor(s) maintaining the undifferentiated state of mouse ES cells via an unidentified signal pathway, while P19 and PCC3 cells produce self‐renewal factors of ES cells other than LIF that were able to activate the STAT3 signal; however, inhibition of STAT3 activation with Janus kinase inhibitor shows only partial impairment on the maintenance of the undifferentiated state of ES cells. Thus, these factors present in EC cells‐derived conditioned medium may be responsible for the self‐renewal capacity of EC and ES cells independently of LIF signaling. 相似文献
944.
Mika Ikeda Hiroshi Kubota Katsuhiro Yoshikawa Masato Kurokawa Tomoyuki Nakamura Shigehiko Suzuki 《Biochemical and biophysical research communications》2009,390(4):1221-36591
Keloid is a fibrotic disease characterized by abnormal accumulation of extracellular matrix in the dermis. The keloid matrix contains excess collagen and glycosaminoglycans (GAGs), but lacks elastic fiber. However, the roles of these matrix components in the pathogenesis of keloid are largely unknown. Here, we show that elastin and DANCE (also known as fibulin-5), a protein required for elastic fiber formation, are not deposited in the extracellular matrix of keloids, due to excess accumulation of chondoitin sulfate (CS), although the expression of elastin and DANCE is not affected. Amount of CS accumulated in the keloid legion was 6.9-fold higher than in normal skin. Fibrillin-1, a scaffold protein for elastic fiber assembly, was abnormally distributed in the keloid matrix. Addition of purified CS to keloid fibroblast culture resulted in abnormal deposition of fibrillin-1, concomitant with significantly decreased accumulation of elastin and DANCE in the extracellular matrix. We propose that CS plays a crucial role in the development of keloid lesions through inhibition of elastic fiber assembly. 相似文献
945.
946.
Two kinds of xyloglucan derivatives (xyloglucan selenious ester and sulfated xyloglucan) were prepared and evaluated on antioxidant activity and antitumor activity. Compared with xyloglucan, xyloglucan derivatives have new bioactivity against oxidative damage and tumor. Furthermore, xyloglucan selenious ester is more potent than sulfated xyloglucan at antioxidant activity and antitumor activity in vitro. The current data suggest for the first time that selenition of xyloglucan significantly increases its bioactivity and the chemical modification of polysaccharide may allow the preparation of derivatives with new properties and a variety of applications. 相似文献
947.
Toru Wada Yosuke Okamura Shinji Takeoka Ryo Sudo Yasuo Ikeda Kazuo Tanishita 《Journal of Biorheology》2009,23(1):35-40
Platelet glycoprotein GPIaIIa is an adhesive protein that recognizes collagen. We have investigated polymerized albumin particles
conjugated with recombinant GPIaIIa (rGPIaIIa-poly Alb) for their platelet-like function. To evaluate the feasibility of these
particles to achieve the hemostatic process, we measured the deformability (Young’s modulus and spring constant) and the adhesive
force of the particles using atomic force microscopy, which can measure the mechanical properties of individual cells. Our
results showed that the Young’s modulus of these particles was 2.3-fold larger than that of natural platelets and 12-fold
larger than that of human red blood cells. The Young’s modulus of the particles may have been determined by the properties
of the polymerized albumin particle, although the glycoprotein of the platelet surface also contributed to the higher modulus.
Our results also showed that the adhesive force of the rGPIaIIa-poly Alb with the collagen ligand was 52% of that of natural
platelets. These two mechanical properties (deformability and adhesive force) of cells or particles, such as rGPIaIIa-poly
Alb, are important specifications for the optimum design of platelet substitutes. 相似文献
948.
Masayuki Ikeda Moritoshi Hirono Takashi Sugiyama Takahiro Moriya Masami Ikeda-Sagara Naomi Eguchi Yoshihiro Urade Tohru Yoshioka 《PloS one》2009,4(11)
Background
The sleep sequence: i) non-REM sleep, ii) REM sleep, and iii) wakefulness, is stable and widely preserved in mammals, but the underlying mechanisms are unknown. It has been shown that this sequence is disrupted by sudden REM sleep onset during active wakefulness (i.e., narcolepsy) in orexin-deficient mutant animals. Phospholipase C (PLC) mediates the signaling of numerous metabotropic receptors, including orexin receptors. Among the several PLC subtypes, the β4 subtype is uniquely localized in the geniculate nucleus of thalamus which is hypothesized to have a critical role in the transition and maintenance of sleep stages. In fact, we have reported irregular theta wave frequency during REM sleep in PLC-β4-deficient mutant (PLC-β4−/−) mice. Daily behavioral phenotypes and metabotropic receptors involved have not been analyzed in detail in PLC-β4−/− mice, however.Methodology/Principal Findings
Therefore, we analyzed 24-h sleep electroencephalogram in PLC-β4−/− mice. PLC-β4−/− mice exhibited normal non-REM sleep both during the day and nighttime. PLC-β4−/− mice, however, exhibited increased REM sleep during the night, their active period. Also, their sleep was fragmented with unusual wake-to-REM sleep transitions, both during the day and nighttime. In addition, PLC-β4−/− mice reduced ultradian body temperature rhythms and elevated body temperatures during the daytime, but had normal homeothermal response to acute shifts in ambient temperatures (22°C–4°C). Within the most likely brain areas to produce these behavioral phenotypes, we found that, not orexin, but group-1 metabotropic glutamate receptor (mGluR)-mediated Ca2+ mobilization was significantly reduced in the dorsal lateral geniculate nucleus (LGNd) of PLC-β4−/− mice. Voltage clamp recordings revealed that group-1 mGluR-mediated currents in LGNd relay neurons (inward in wild-type mice) were outward in PLC-β4−/− mice.Conclusions/Significance
These lines of evidence indicate that impaired LGNd relay, possibly mediated via group-1 mGluR, may underlie irregular sleep sequences and ultradian body temperature rhythms in PLC-β4−/− mice. 相似文献949.
Ayumi Ikeda Esteban C. Gabazza John Morser Ichiro Imoto Mikihito Kuroda Corina N. D'Alessandro-Gabazza Kenichiro Hara Daniel Boveda Ruiz Paloma Gil Bernabe Masaki Katsurahara Masaaki Toda Yoshinao Kobayashi Yutaka Yano Yasuhiro Sumida Koji Suzuki Osamu Taguchi Yoshiyuki Takei 《Helicobacter》2009,14(2):147-155
Thrombin-activatable fibrinolysis inhibitor (TAFI) plays a role in the regulation of coagulation and inflammation. In addition to inhibiting the fibrinolytic system, TAFI may also regulate the bradykinin and complement systems. We hypothesized that TAFI also plays a role in defense mechanisms of the gastric mucosa during Helicobacter pylori infection. This study comprised 65 patients with gastroduodenal disorders: 41 patients with H. pylori infection, 13 without, and 11 patients with cured H. pylori infection. The gastric intramucosal concentrations of TAFI were measured by enzyme immunoassay. The gastric levels of TAFI and plasminogen activator inhibitor-1 were significantly increased in patients with H. pylori compared to those without infection or cured H. pylori . The presence of TAFI was detected in gastric mucosal epithelial cells. The concentration of TAFI was correlated with the degree of gastric mucosal atrophy, inflammation, and disease activity. These results show that TAFI is present in the gastric mucosa and that it may play a role in the pathogenesis of H. pylori infection-associated gastroduodenal disorders. 相似文献
950.
Kentaro Morita Tomoyuki Yamamoto Naoki Fusada Mamoru Komatsu Haruo Ikeda Nobutaka Hirano Hideo Takahashi 《Molecular genetics and genomics : MGG》2009,282(6):607-616
We have previously shown that, in vivo, the integration system based on the gene encoding the TG1 integrase and the corresponding
attB
TG1
and attP
TG1
sites works well not only in Streptomyces strains, but also in Escherichia coli. Furthermore, the attachment sites for TG1 integrase are distinct from those of ϕC31 integrase. In this report, we expressed
TG1 integrase as a GST-TG1 integrase fusion protein and then used affinity separation and specific cleavage to release purified
integrase. Conditions for in vitro recombination were established using the purified TG1 integrase and its cognate attP
TG1
and attB
TG1
sites. TG1 integrase efficiently catalyzed a site-specific recombination between attB
TG1
and attP
TG1
sites irrespective of their substrate topology. The minimal sequences of attP
TG1
and attB
TG1
sites required for the substrates of TG1 integrase were demonstrated to be 43 and 39-bp, respectively. These results provide
the basic features of the TG1 integrase system to be used as biotechnological tools, as well as to unravel the mechanism of
the serine integrase. 相似文献