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991.
Tomohito Matsuo Yukiko Noguchi Mieko Shindo Yoshifumi Morita Yoshie Oda Eiko Yoshida Hiroko Hamada Mine Harada Yuichi Shiokawa Takahiro Nishida Ryuji Tominaga Yoshikane Kikushige Koichi Akashi Jun Kudoh Nobuyoshi Shimizu Yuka Tanaka Tsukuru Umemura Taketoshi Taniguchi Akihiko Yoshimura Takashi Kobayashi Masao Mitsuyama Hironori Kurisaki Hitoshi Katsuta Seiho Nagafuchi 《Gene》2013
Although mutations of autoimmune regulator (AIRE) gene are responsible for autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED), presenting a wide spectrum of many characteristic and non-characteristic clinical features, some patients lack AIRE gene mutations. Therefore, something other than a mutation, such as dysregulation of AIRE gene, may be a causal factor for APECED or its related diseases. However, regulatory mechanisms for AIRE gene expression and/or translation have still remained elusive. We found that IL-2-stimulated CD4+ T (IL-2T) cells showed a high expression of AIRE gene, but very low AIRE protein production, while Epstein–Barr virus-transformed B (EBV-B) cells express both AIRE gene and AIRE protein. By using microarray analysis, we could identify miR-220b as a possible regulatory mechanism for AIRE gene translation in IL-2T cells. Here we report that miR-220b significantly reduced the expression of AIRE protein in AIRE gene with 3′UTR region transfected 293T cells, whereas no alteration of AIRE protein production was observed in the open reading frame of AIRE gene alone transfected cells. In addition, anti-miR-220b reversed the inhibitory function of miR-220b for the expression of AIRE protein in AIRE gene with 3′UTR region transfected cells. Moreover, when AIRE gene transfected cells with mutated 3′UTR were transfected with miR-220b, no reduction of AIRE protein production was observed. Taken together, it was concluded that miR-220b inhibited the AIRE gene translation through the 3′UTR region of AIRE gene, indicating that miR-220b could serve as a regulator for human AIRE gene translation. 相似文献
992.
Stability of heterochiral hybrid membrane made of bacterial sn-G3P lipids and archaeal sn-G1P lipids
The structure of membrane lipids in Archaea is different from those of Bacteria and Eucarya in many ways including the chirality of the glycerol backbone. Until now, heterochiral membranes were believed to be unstable; thus, no cellular organism could have existed before the separation of the groups of life. In this study, we tested the formation of heterochiral hybrid membrane made of Bacterial sn-glycerol-3-phosphate-type polar lipid and Archaeal sn-glycerol-1-phosphate-type polar lipid using the fluorescence probe. The stability of the hybrid liposomes made of phosphatidylethanolamines or phosphatidylcholines or polar lipids of thermophilic Bacteria and polar lipids of Archaea were investigated. The hybrid liposomes are all stable compared with homochiral liposome made of dimyristoylphosphatidylethanolamine and dipalmitoylphosphatidylcholine. However, the stability was drastically changed with increasing carbon chain length. Accordingly, "chirality" may not be but chain length is important. From these results, we suggest that the heterochiral hybrid membrane could be used as the membrane lipid for the last universal common ancestor (Commonote) before the emergence of Archaea and Bacteria. 相似文献
993.
Takashi Yamane Hiroya Higuchi Akihiko Takahashi Masuhiro Ishimoto 《Applied Entomology and Zoology》2011,46(4):559-564
To develop new and improved pest management strategies against Trigonotylus caelestialium (Kirkaldy) (Heteroptera: Miridae), a major pest of rice in Japan, it is important to understand the mating behavior of this
species. In this study, we examined the effect of mating on subsequent mating receptivity and longevity in female T. caelestialium. After mating, females temporarily exhibited decreased mating receptivity. In addition, the cumulative remating frequency
of females that mated with a male that had just mated with another female was higher than that of females who mated with virgin
males. As a result, we hypothesized that the male ejaculate reduces female mating receptivity. Furthermore, mated females
survived longer without food and water than virgin females; on the other hand, the life span of mated females with access
to food and water was less than that for virgin females. 相似文献
994.
Takahiko Hamaguchi Hiroki Wakabayashi Akihiko Matsumine Akihiro Sudo Atsumasa Uchida 《Biochemical and biophysical research communications》2011,(3):2104
In the evolution of cancer, tumor necrosis factor-alpha (TNF-α) plays a paradoxical role. High doses induce significant anticancer effects, but conversely, physiologic and pathologic levels of TNF-α may be involved in cancer promotion, tumor growth, and metastasis.Infliximab is a chimeric murine monoclonal antibody that binds with high affinity to soluble and membrane TNF-α and inhibits binding of TNF-α to its receptors. In the present study, we investigated the effect of infliximab, a TNF-α antagonist, on breast cancer aggressiveness and bone metastases.Infliximab greatly reduced cell motility and bone metastases in a metastatic breast cancer cell line, MDA-MB-231. The mechanism of bone metastasis inhibition involved decreased expression of CXC chemokine receptor 4 (CXCR4) and increased expression of decorin, which is the prototype of an expanding family of small leucine-rich proteoglycans. These results suggest a novel role for TNF-α inhibition in the reduction or prevention of bone metastases in this breast cancer model. Our study suggests that inhibition of TNF-α using infliximab may become a preventive therapeutic option for breast cancer. 相似文献
995.
Panida?Prawitwong Rattiya?Waeonukul Chakrit?Tachaapaikoon Patthra?Pason Khanok?Ratanakhanokchai Lan?Deng Junjarus?Sermsathanaswadi Krisna?Septiningrum Yutaka?Mori Akihiko?KosugiEmail author 《Biotechnology for biofuels》2013,6(1):184
Background
Cellulases continue to be one of the major costs associated with the lignocellulose hydrolysis process. Clostridium thermocellum is an anaerobic, thermophilic, cellulolytic bacterium that produces cellulosomes capable of efficiently degrading plant cell walls. The end-product cellobiose, however, inhibits degradation. To maximize the cellulolytic ability of C. thermocellum, it is important to eliminate this end-product inhibition.Results
This work describes a system for biological saccharification that leads to glucose production following hydrolysis of lignocellulosic biomass. C. thermocellum cultures supplemented with thermostable beta-glucosidases make up this system. This approach does not require any supplementation with cellulases and hemicellulases. When C. thermocellum strain S14 was cultured with a Thermoanaerobacter brockii beta-glucosidase (CglT with activity 30 U/g cellulose) in medium containing 100 g/L cellulose (617 mM initial glucose equivalents), we observed not only high degradation of cellulose, but also accumulation of 426 mM glucose in the culture broth. In contrast, cultures without CglT, or with less thermostable beta-glucosidases, did not efficiently hydrolyze cellulose and accumulated high levels of glucose. Glucose production required a cellulose load of over 10 g/L. When alkali-pretreated rice straw containing 100 g/L glucan was used as the lignocellulosic biomass, approximately 72% of the glucan was saccharified, and glucose accumulated to 446 mM in the culture broth. The hydrolysate slurry containing glucose was directly fermented to 694 mM ethanol by addition of Saccharomyces cerevisiae, giving an 85% theoretical yield without any inhibition.Conclusions
Our process is the first instance of biological saccharification with exclusive production and accumulation of glucose from lignocellulosic biomass. The key to its success was the use of C. thermocellum supplemented with a thermostable beta-glucosidase and cultured under a high cellulose load. We named this approach biological simultaneous enzyme production and saccharification (BSES). BSES may resolve a significant barrier to economical production by providing a platform for production of fermentable sugars with reduced enzyme amounts.996.
Satoshi Ikeda Katsuhiro Harada Akihiko Ohwatashi Yurie Kamikawa Akira Yoshida Kazumi Kawahira 《PloS one》2013,8(3)
Background and Purpose
Rat models of photochemically induced cerebral infarction have been readily studied, but to date there are no reports of transcranial photochemically induced infarctions in the marmoset. In this report, we used this non-human primate as a model of cerebral thrombosis and observed the recovery process.Methods
Five common marmosets were used. Cerebral ischemia was produced via intravascular thrombosis induced by an intravenous injection of Rose Bengal and irradiation with green light. After inducing cerebral infarction, we observed the behavior of marmosets via a continuous video recording. We evaluated maximum speed, mean speed, and distance traveled in 1 min. In addition, we evaluated scores for feeding behavior, upper limb grip, and lower limb grip. We confirmed the infarct area after cerebral infarction using 2,3,5-triphenyltetrazolium chloride staining in a separate marmoset.Results
We found functional decreases 2 days after creating the cerebral infarction in all measurements. Total distance traveled, average speed, upper limb score, and feeding behavior score did not recover to pre-infarction levels within 28 days. Maximum speed in 1 min and lower limb score recovered 28 days after infarction as compared to pre-infarction levels. We confirmed the infarct area of 11.4 mm×6.8 mm as stained with 2,3,5-triphenyltetrazolium chloride.Conclusion
We were able to create a primate photothrombosis-induced cerebral infarction model using marmosets and observe functional recovery. We suggest that this is a useful model for basic research of cerebral infarction. 相似文献997.
Shinji Miwa Akihiko Takeuchi Hiroko Ikeda Toshiharu Shirai Norio Yamamoto Hideji Nishida Katsuhiro Hayashi Yoshikazu Tanzawa Hiroaki Kimura Kentaro Igarashi Hiroyuki Tsuchiya 《PloS one》2013,8(8)
Background
A variety of surgical procedures are now available for tissue reconstruction after osteosarcoma excision, and an important prognostic factor is the evaluation of response to chemotherapy using histology. Although tumor-bearing autografts are useful tools for reconstruction, re-use of the primary tumor may make it difficult to assess the histological response to chemotherapy, since the entire tumor cannot be analyzed. Here, we analyzed the prognostic value of the histological response in the patients who received frozen tumor-bearing autografts for reconstruction.Method
Retrospective analysis of the medical records of 51 patients with high-grade osteosarcoma of the extremities was performed. All patients received reconstruction using frozen tumor-bearing autografts. Tumor necrosis was evaluated in extraskeletal masses and cancellous bone.Results
Five-year overall survival of patients with good and poor response to chemotherapy was 82.9% and 46.4%, respectively (P = 0.044), and 5-year event-free survival was 57.7% and 36.0%, respectively (P = 0.329). Multivariate analysis revealed that a poor histological response to chemotherapy was a significant prognostic factor for overall survival (P = 0.033).Conclusion
Histological response is an important and reliable prognostic factor in patients undergoing reconstruction using frozen tumor-bearing autografts. 相似文献998.
Nobuyuki Kurosawa Rika Fujimoto Tatsuhiko Ozawa Takahiro Itoyama Naoki Sadamori Masaharu Isobe 《PloS one》2013,8(1)
Background
Adult T-cell leukemia/lymphoma (ATLL) develops in a small proportion of human T-cell leukemia virus type I (HTLV-I)-infected individuals. However, the mechanism by which HTLV-I causes ATLL has not been fully elucidated. To provide fundamental insights into the multistep process of leukemogenesis, we have mapped the chromosomal abnormalities in 50 ATLL cases to identify potential key regulators of ATLL.Results
The analysis of breakpoints in one ATLL case with the translocations t(14;17)(q32;q22-23) resulted in the identification of a Kruppel zinc finger gene, BCL11B, which plays a crucial role in T-cell development. Among the 7 ATLL cases that we examined by immunofluorescence analysis, 4 displayed low and one displayed moderate BCL11B signal intensities. A dramatically reduced level of the BCL11B protein was also found in HTLV-I-positive T-cell lines. The ectopic expression of BCL11B resulted in significant growth suppression in ATLL-derived cell lines but not in Jurkat cells.Conclusions
Our genetic and functional data provide the first evidence that a reduction in the level of the BCL11B protein is a key event in the multistep progression of ATLL leukemogenesis. 相似文献999.
Masazumi Nishimoto Miyuki Katano Toshiyuki Yamagishi Tomoaki Hishida Masayoshi Kamon Ayumu Suzuki Masataka Hirasaki Yoko Nabeshima Yo-ichi Nabeshima Yukako Katsura Yoko Satta Janine E. Deakin Jennifer A. Marshall Graves Yoko Kuroki Ryuichi Ono Fumitoshi Ishino Masatsugu Ema Satoru Takahashi Hidemasa Kato Akihiko Okuda 《PloS one》2013,8(7)
Embryogenesis in placental mammals is sustained by exquisite interplay between the embryo proper and placenta. UTF1 is a developmentally regulated gene expressed in both cell lineages. Here, we analyzed the consequence of loss of the UTF1 gene during mouse development. We found that homozygous UTF1 mutant newborn mice were significantly smaller than wild-type or heterozygous mutant mice, suggesting that placental insufficiency caused by the loss of UTF1 expression in extra-embryonic ectodermal cells at least in part contributed to this phenotype. We also found that the effects of loss of UTF1 expression in embryonic stem cells on their pluripotency were very subtle. Genome structure and sequence comparisons revealed that the UTF1 gene exists only in placental mammals. Our analyses of a family of genes with homology to UTF1 revealed a possible mechanism by which placental mammals have evolved the UTF1 genes. 相似文献
1000.
Akihiko Nakamura Hideshi Niimura Kazuyo Kuwabara Toshiro Takezaki Emi Morita Kenji Wakai Nobuyuki Hamajima Yuichiro Nishida Tanvir Chowdhury Turin Sadao Suzuki Keizo Ohnaka Hirokazu Uemura Etsuko Ozaki Satoyo Hosono Haruo Mikami Michiaki Kubo Hideo Tanaka 《PloS one》2013,8(12)