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991.
Yamada M Kuwano K Maeyama T Hamada N Yoshimi M Nakanishi Y Kasper M 《Histochemistry and cell biology》2008,129(4):453-462
epithelial–mesenchymal transition (EMT) has been considered to be involved in organ fibrogenesis. However, there is few direct
evidence of this process in the pathophysiology of pulmonary fibrosis in vivo. Therefore, we tried to verify the involvement
of this process in the development of pulmonary fibrosis. Since the co-expressions of epithelial and mesenchymal markers are
thought to be a marker of EMT, we performed dual-immuunohistochemistry to assess the co-expressions of these proteins in lung
tissues from bleomycin-induced pulmonary fibrosis in mice, and from patients with idiopathic pulmonary fibrosis, and nonspecific
interstitial pneumonia. Double positive cells for epithelial markers including E-cadherin, T1α, or aquaporin 5, and a mesenchymal
markers α-smooth muscle actin or vimentin were not found in bleomycin-induced pulmonary fibrosis in mice. Double positive
cells for E-cadherin, ICAM-1, LEA, CD44v9, or SP-A and α-smooth muscle actin or vimentin were not found in lung tissues from
normal lung parenchyma, idiopathic pulmonary fibrosis and nonspecific interstitial pneumonia. These results offer at least
two possibilities. One is that EMT does not occur in IPF or bleomycin-induced pulmonary fibrosis in mice. Another is that
EMT may occur in pulmonary fibrosis but the time during this transition in which cells express detectable levels of epithelial
and mesenchymal markers is too small to be detected by double immunohistochemistry. 相似文献
992.
Kurome M Tomii R Ueno S Hiruma K Matsumoto S Okumura K Nakamura K Matsumoto M Kaji Y Endo F Nagashima H 《Cloning and stem cells》2008,10(2):277-286
To achieve tissue stem cell transplantation in clinical settings, translational studies using large animal models are essential to confirm the efficacy and safety of therapy. Therefore, with the ultimate objective of constructing a porcine model of stem cell transplantation in the present study we attempted to clone pigs using porcine salivary gland-derived progenitor cells (pSGPs) as nuclear donors. Normal chromosomal compositions of pSGPs were maintained after five to eight passages (73%, 41 of 56). Cell cycle was efficiently synchronized in G(0)/G(1) phase after 2 days of serum-starved culture (79%). Characteristics of multipotent pSGPs, that is, CD49f and intracellular laminin staining patterns, were unchanged after serum-starved culture. Developmental rate of blastocysts from embryos reconstructed using pSGPs as nuclear donors was significantly higher when compared to embryos reconstructed using fetal fibroblasts (27.7%, 38 of 137 vs. 12.8%, 17 of 138; p < 0.05). When a total of 615 reconstructed embryos were transplanted into four recipient gilts, all gilts became pregnant and produced 12 piglets. These findings suggest that pSGPs represent appropriate donor cells for porcine somatic cell nuclear transfer. 相似文献
993.
In this paper, the enhancement of thermal properties of polymer-coated silver nanoparticles by the addition of plasmid DNA is described. Nanoparticles of noble metals such as gold and silver possess specific characteristics by virtue of their quantum size effects. Therefore, noble metal nanoparticles are used for chemical sensing and biosensing applications based on their localized surface plasmon resonance absorption that can be measured in the visible region. The polyvinylpyrrolidone (PVP)-coated noble metal nanoparticles, in particular, with high dispersion ability in water, offer several advantages for sensing applications. However, some difficulties are encountered in the use of these PVP-coated noble metal nanoparticles for sensing applications due to their poor thermal properties. To improve the thermal properties of PVP-coated noble metal nanoparticles, we found that the addition of plasmid DNA to PVP-coated silver nanoparticles enhances their thermal properties due to good thermal stability of DNA. The introduction of plasmid DNA into PVP-coated silver nanoparticle dispersion enhanced the thermal properties through the formation of a complex between the nanoparticles and plasmid DNA. Furthermore, other polymers such as proteins and polyethylene glycol did not enhance the thermal properties of PVP-coated silver nanoparticles. Thus, the PVP-coated silver nanoparticle–plasmid DNA complex with enhanced thermal properties has a great potential for use in medical and drug delivery applications. 相似文献
994.
995.
Kamo T Endo M Sato M Kasahara R Yamaya H Hiradate S Fujii Y Hirai N Hirota M 《Phytochemistry》2008,69(5):1166-1172
Cyanamide (NH2CN) has recently been proven to be a natural product, although it has been synthesized for over 100 years for agricultural and industrial purposes. The distribution of natural cyanamide appears to be limited, as indicated by our previous investigation of 101 weed species. In the present study, to investigate the distribution of natural cyanamide in Vicia species, we monitored the cyanamide contents in V. villosa subsp. varia, V. cracca, and V. amoena during their pre-flowering and flowering seasons. It was confirmed that V. cracca was superior to V. villosa subsp. varia in accumulating natural cyanamide, and that V. amoena was unable to biosynthesize this compound under laboratory condition examined. The localization of cyanamide in the leaves of V. villosa subsp. varia seedlings was also clarified. In a screening study to find cyanamide-biosynthesizing plants, only Robinia pseudo-acacia was found to contain cyanamide among 452 species of higher plants. We have investigated 553 species to date, but have so far found the ability to biosynthesize cyanamide in only three species, V. villosa subsp. varia, V. cracca and R. pseudo-acacia. 相似文献
996.
Kiminori Ohta Takumi Ogawa Yasuyuki Endo 《Bioorganic & medicinal chemistry letters》2017,27(17):4030-4033
The selectivity and the binding affinity of previously reported carborane-containing ligands 2 and 3 toward ERβ remains to be optimized. To improve their biological profiles, a series of iodinated carboranyl phenol derivatives (4–6) were designed and synthesized as prospective ERβ-selective ligands with high affinity. Several iodinated carboranyl phenols showed high relative binding affinity (RBA) values for both ERs, and especially for ERβ, due to suitable hydrophobic interactions of the iodine atoms with the hydrophobic amino acid residues of the ERβ ligand-binding domains. Among these derivatives, 9,10-diiodo-m-carborane 5f exhibited a more than 100% increase of the RBA values toward ERβ, a 14-fold increased selectivity for ERβ over ERα, and ER-agonistic activity in MCF-7 cell proliferation assays. 相似文献
997.
Isao Sakurada Toshiya Endo Katsuyoshi Hikita Tomokazu Hirabayashi Yoshitaka Hosaka Yutaka Kato Yoshitaka Maeda Shigeki Matsumoto Takashi Mizuno Hiroshi Nagasue Teruyuki Nishimura Shunsuke Shimada Mikihiko Shinozaki Keiko Taguchi Katsutoshi Takeuchi Tooru Yokoyama Alan Hruza Paul Reichert Shoji Furusako 《Bioorganic & medicinal chemistry letters》2017,27(11):2622-2628
Using structure based drug design, novel aminobenzisoxazoles as coagulation factor IXa inhibitors were designed and synthesized. Highly selective inhibition of FIXa over FXa was demonstrated. Anticoagulation profile of selected compounds was evaluated by aPTT and PT tests. In vitro ADMET and pharmacokinetic (PK) profiles were also evaluated. 相似文献
998.
Hattori Shuichiro Watanabe Masanori Endo Toshiro Togii Hisashi Sasaki Ken 《World journal of microbiology & biotechnology》2001,17(3):279-285
By applying an external magnetic field (800–3000 G, 0.08–0.30 T) using permanent magnets to the aeration vessel of an activated sludge culture, the sedimentation of activated sludge was enhanced and chemical oxygen demand (COD) removal was also improved in an indoor continuous culture system. Adding a small amount of iron(III) chloride (FeCl3, less than 0.1%, w/v) stimulated these enhancements. The possibility was suggested that the small amount of molecular iron incorporated into the activated sludge stimulated the flocculation and sedimentation by external magnetization. 相似文献
999.
1000.
Makoto Nogami Junji Shiga Akihiro Takatsu Noriko Endo Ikuo Ishiyama 《The Histochemical journal》2001,33(2):87-90
Atrial natriuretic peptide (ANP) was originally isolated from cardiac atria, and has potent natriuretic, diuretic, and vasorelaxant properties. It has been localized in neurons and astrocytes in the cerebral cortex and the white matter. We hypothesize that glial ANP may contribute to the regulation of cerebral blood flow in brain infarction. In order to elucidate this possible role, the immunohistochemistry of ANP was studied in cases of brain infarction and in other cases of brain trauma for comparison. A statistically significant increase in the number of ANP-immunoreactive glial cells (mainly astrocytes) was observed in the white matter surrounding the brain infarction compared with the intact area. No statistically significant increase in ANP-immunoreactive glial cell number was observed in the cerebral white matter from brain haemorrhage, contusion and control cases. Our results indicate that glial ANP may increase in number in brain infarction, and that it may be involved in the regulation of the cerebral blood flow in the infarcted area. 相似文献