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711.
712.
Morita I Nakagaki H Kato K Murakami T Tsuboi S Hayashizaki J Toyama A Hashimoto M Simozato T Morishita N Kawanaga T Igo J Sheiham A 《Gerodontology》2007,24(1):47-51
Objectives: The objective of this study was to assess which factors affected the maintenance of more than 20 teeth in Japanese patients aged 80 years and older, using a life‐course perspective. Subjects and methods: The oral examination was carried out by dentists. The questionnaire asked about family background, background during various stages of growing up, tooth brushing, snacking, job history, health examination, war experience, number of children, oral health condition and dietary preferences. Some of the questions asked about conditions when they were a primary school student, 20 years old, 40 years old and 60 years old. Multivariable logistic‐regression analysis was used to adjust for sex at significant life stages. Results: The group with mothers who did not prefer sweet food had an approximately four times greater chance of having ≥20 teeth compared with the group with mothers who preferred sweet food. Those participants who did not prefer sweet food themselves were approximately three to five times more likely to be in the ≥20 tooth group compared with those who preferred sweet food at all stages of their life course. Non‐smokers and those who quit smoking were three times more likely to be in the ≥20 tooth group than those who smoked throughout the years from 20 to 60 years of age. Conclusions: Factors associated with the maintenance of a sufficient number of functioning teeth were: not having a mother with a preference for sweet food, not having a preference for sweet food themselves and not smoking over a long period. 相似文献
713.
Kosuke Saito Keiko Maekawa Kirk L. Pappan Masayo Urata Masaki Ishikawa Yuji Kumagai Yoshiro Saito 《Metabolomics : Official journal of the Metabolomic Society》2014,10(3):402-413
Endobiotic metabolites are associated with biological processes in the body and therefore may serve as biomarkers for disease states or therapeutic efficacy and toxicity. However, information is limited regarding how differences between blood matrices, patient backgrounds, and sample handling affect human metabolite profiles. Our objective was to obtain metabolite profiles from Caucasian individuals, based on different matrices (plasma and serum), subject backgrounds (male/female and young/old), and storage conditions (2 or 10 freeze–thaw cycles). In total, 297 metabolites were detected by LC/MS and GC/MS, and more than 75 % of them were highly represented in all sample groups. The multivariate discriminant analysis (OPLS-DA as a model) singled out the matrix type as the most important variable influencing global metabolic profiles; that is, more than 100 metabolites were significantly different based on the matrix type. The influence of subject backgrounds on global metabolic profiles was consistent between plasma and serum. Age-associated differences were more predominant in females than males, whereas gender-associated differences were more prevalent in young subjects than old individuals were. The relative standard deviation of metabolite levels in subjects with the same background ranked from 0.1 to 1.5. Moreover, the changes of metabolite levels caused by freeze–thaw cycles were limited, and the effect was more prominent in plasma than serum. These data demonstrate the impact of matrix, age, gender, and freeze–thaw cycles on the metabolite profiles and reveal metabolites affected by these factors. Thus, our results provide would useful fundamental information for exploring and qualifying biomarkers for clinical applications. 相似文献
714.
Kenichi Ishibashi Yasuko Tanaka Yoshiyuki Morishita 《Biochimica et Biophysica Acta (BBA)/General Subjects》2014
Background
The mammalian two superaquaporins, AQP11 and AQP12, are present inside the cell and their null phenotypes in mice suggest their unusual functions.Scope of review
The surveyed literature on these superaquaporins and our unpublished data has been incorporated to speculate their roles.Major conclusions
AQP11 and AQP12 have unique NPA boxes with a signature cysteine residue. Although some water permeability of AQP11 was demonstrated in liposomes and cultured cells, its permeability to glycerol is unknown. The function of AQP12 still remains to be clarified. AQP11 null mice develop polycystic kidneys following large intracellular vacuoles in the proximal tubule, which may be caused by ER stress or vesicle fusion failure. The role of AQP11 in the kidney and liver seems to alleviate the tissue damage and facilitate the recovery. Its expression in the sperm, thymus and brain suggests its potential roles in these organs in spite of the apparently normal null phenotype. Although AQP12 null mice appear normal, they suffer from severe pancreatitis, suggesting its role in the fusion of zymogen granules.General significance
As many issues are unsolved, the clarification of the function and roles of the superaquaporin may lead to the identification of new roles of AQPs. This article is part of a Special Issue entitled Aquaporins. 相似文献715.
Hiroyuki Suzuki Hidehiro Oku Taeko Horie Seita Morishita Masahiro Tonari Kazuma Oku Akiko Okubo Teruyo Kida Masashi Mimura Masanori Fukumoto Shota Kojima Shinji Takai Tsunehiko Ikeda 《PloS one》2014,9(12)
The purpose of this study was to determine the temporal and spatial changes in the expression of AQP4 and AQP9 in the optic nerve after it is crushed. The left optic nerves of rats were either crushed (crushed group) or sham operated (sham group), and they were excised before, and at 1, 2, 4, 7, and 14 days later. Four optic nerves were pooled for each time point in both groups. The expression of AQP4 and AQP9 was determined by western blot analyses. Immunohistochemistry was used to determine the spatial expression of AQP4, AQP9, and GFAP in the optic nerve. Optic nerve edema was determined by measuring the water content in the optic nerve. The barrier function of the optic nerve vessels was determined by the extravasated Evans blue dye on days 7 and 14. The results showed that the expression of AQP4 was increased on day 1 but the level was significantly lower than that in the sham group on days 4 and 7 (P<0.05). In contrast, the expression of AQP9 gradually increased, and the level was significantly higher than that in the sham group on days 7 and 14 (P<0.05, Tukey-Kramer). The down-regulation of AQP4 was associated with crush-induced optic nerve edema, and the water content of the nerve was significantly increased by 4.3% in the crushed optic nerve from that of the untouched fellow nerve on day 7. The expression of AQP4 and GFAP was reduced at the crushed site where AQP4-negative and AQP9-positive astrocytes were present. The barrier function was impaired at the crushed site on days 7 and 14, restrictedly where AQP4-negative and AQP9-positive astrocytes were present. The presence of AQP9-positive astrocytes at the crushed site may counteract the metabolic damage but this change did not fully compensate for the barrier function defect. 相似文献
716.
Hoshimi Kanemura Masahiro J. Go Masayuki Shikamura Naoki Nishishita Noriko Sakai Hiroyuki Kamao Michiko Mandai Chikako Morinaga Masayo Takahashi Shin Kawamata 《PloS one》2014,9(1)
Basic studies of human pluripotential stem cells have advanced rapidly and stem cell products are now seeing therapeutic applications. However, questions remain regarding the tumorigenic potential of such cells. Here, we report the tumorigenic potential of induced pluripotent stem cell (iPSC)-derived retinal pigment epithelium (RPE) for the treatment of wet-type, age-related macular degeneration (AMD). First, immunodeficient mouse strains (nude, SCID, NOD-SCID and NOG) were tested for HeLa cells’ tumor-forming capacity by transplanting various cell doses subcutaneously with or without Matrigel. The 50% Tumor Producing Dose (TPD50 value) is the minimal dose of transplanted cells that generated tumors in 50% of animals. For HeLa cells, the TPD50 was the lowest when cells were embedded in Matrigel and transplanted into NOG mice (TPD50 = 101.1, n = 75). The TPD50 for undifferentiated iPSCs transplanted subcutaneously to NOG mice in Matrigel was 102.12; (n = 30). Based on these experiments, 1×106 iPSC-derived RPE were transplanted subcutaneously with Matrigel, and no tumor was found during 15 months of monitoring (n = 65). Next, to model clinical application, we assessed the tumor-forming potential of HeLa cells and iPSC 201B7 cells following subretinal transplantation of nude rats. The TPD50 for iPSCs was 104.73 (n = 20) and for HeLa cells 101.32 (n = 37) respectively. Next, the tumorigenicity of iPSC-derived RPE was tested in the subretinal space of nude rats by transplanting 0.8–1.5×104 iPSC-derived RPE in a collagen-lined (1 mm×1 mm) sheet. No tumor was found with iPSC-derived RPE sheets during 6–12 months of monitoring (n = 26). Considering the number of rodents used, the monitoring period, the sensitivity of detecting tumors via subcutaneous and subretinal administration routes and the incidence of tumor formation from the iPSC-derived RPE, we conclude that the tumorigenic potential of the iPSC-derived RPE was negligible. 相似文献
717.
D Hagiwara H Arima Y Morishita L Wenjun Y Azuma Y Ito H Suga M Goto R Banno Y Sugimura A Shiota N Asai M Takahashi Y Oiso 《Cell death & disease》2014,5(3):e1148
Familial neurohypophysial diabetes insipidus (FNDI) characterized by progressive polyuria is mostly caused by mutations in the gene encoding neurophysin II (NPII), which is the carrier protein of the antidiuretic hormone, arginine vasopressin (AVP). Although accumulation of mutant NPII in the endoplasmic reticulum (ER) could be toxic for AVP neurons, the precise mechanisms of cell death of AVP neurons, reported in autopsy studies, remain unclear. Here, we subjected FNDI model mice to intermittent water deprivation (WD) in order to promote the phenotypes. Electron microscopic analyses demonstrated that, while aggregates are confined to a certain compartment of the ER in the AVP neurons of FNDI mice with water access ad libitum, they were scattered throughout the dilated ER lumen in the FNDI mice subjected to WD for 4 weeks. It is also demonstrated that phagophores, the autophagosome precursors, emerged in the vicinity of aggregates and engulfed the ER containing scattered aggregates. Immunohistochemical analyses revealed that expression of p62, an adapter protein between ubiquitin and autophagosome, was elicited on autophagosomal membranes in the AVP neurons, suggesting selective autophagy induction at this time point. Treatment of hypothalamic explants of green fluorescent protein (GFP)-microtubule-associated protein 1 light chain 3 (LC3) transgenic mice with an ER stressor thapsigargin increased the number of GFP-LC3 puncta, suggesting that ER stress could induce autophagosome formation in the hypothalamus of wild-type mice as well. The cytoplasm of AVP neurons in FNDI mice was occupied with vacuoles in the mice subjected to WD for 12 weeks, when 30–40% of AVP neurons are lost. Our data thus demonstrated that autophagy was induced in the AVP neurons subjected to ER stress in FNDI mice. Although autophagy should primarily be protective for neurons, it is suggested that the organelles including ER were lost over time through autophagy, leading to autophagy-associated cell death of AVP neurons. 相似文献
718.
Feng Xu Yusuke Sudo Sho Sanechika Junpei Yamashita Sho Shimaguchi Shun-ichiro Honda Chiho Sumi-Ichinose Masayo Mori-Kojima Rieko Nakata Tadaomi Furuta Minoru Sakurai Masahiro Sugimoto Tomoyoshi Soga Kazunao Kondo Hiroshi Ichinose 《FEBS letters》2014
Quinonoid dihydropteridine reductase (QDPR) catalyzes the regeneration of tetrahydrobiopterin (BH4), a cofactor for monoamine synthesis, phenylalanine hydroxylation and nitric oxide production. Here, we produced and analyzed a transgenic Qdpr−/− mouse model. Unexpectedly, the BH4 contents in the Qdpr−/− mice were not decreased and even increased in some tissues, whereas those of the oxidized form dihydrobiopterin (BH2) were significantly increased. We demonstrated that unlike the wild-type mice, dihydrofolate reductase regenerated BH4 from BH2 in the mutants. Furthermore, we revealed wide alterations in folate-associated metabolism in the Qdpr−/− mice, which suggests an interconnection between folate and biopterin metabolism in the transgenic mouse model. 相似文献
719.
The binding of herbicides to the phylloquinone-(primary electron acceptor A1)-binding site in green plant photosystem (PS) I reaction centers is shown. Dissociation constants (Kd) of various herbicides to the phylloquinone-binding site were estimated by analyzing their competitive inhibition of the reconstitution of the phylloquinone analogue, menadione (vitamin K3), to the phylloquinone-extracted spinach PS I particles. The phylloquinone-binding site was found to bind o-phenanthroline (Kd = 1.2 × 10−4 M), but only weak binding was observed with atrazine (Kd > 10−2 M), although both are known to bind specifically to the quinone-(QB)-binding site in reaction centers of purple photosynthetic bacteria or PS II. The inhibitors of the cytochrome b/c1(ƒ) complex, myxothiazol (Kd=9.5 × 10−6 M) or antimycin A (Kd = 2.8 × 10−6 M), also strongly bound to the phylloquinone site. This is the first report showing that the PS I reaction center complex also has a herbicide-binding site, although the site is probably not sensitive in vivo to these herbicides due to its higher affinity for phylloquinone than herbicides. The inhibitor specificity of the PS I phylloquinone site is different from that of the other quinone-functioning sites in the photosynthetic or respiratory electron-transfer chain, suggesting it to have a unique structure. 相似文献
720.
Ohashi K Oshima K Tachikawa M Morikawa N Hashimoto Y Ito M Mori H Kuribayashi T Terasaki AG 《Cell motility and the cytoskeleton》2005,61(4):214-225
We determined the full cDNA sequences of chicken gizzard filamin and cgABP260 (chicken gizzard actin-binding protein 260). The primary and secondary structures predicted by these sequences were similar to those of chicken retina filamin and human filamins. Like mammals, chickens have 3 filamin isoforms. Comparison of their amino acid sequences indicated that gizzard filamin, retina filamin, and cgABP260 were the counterparts of human FLNa (filamin a), b, and c, respectively. Antibodies against the actin-binding domain (ABD) of these 3 filamin isoforms were raised in rabbits. Using immunoabsorption and affinity chromatography, we prepared the monospecific antibody against the ABD of each filamin. In immunoblotting, the antibody against the gizzard filamin ABD detected a single band in gizzard, but not in striated muscles or brain. In brain, only the antibody against the retina filamin ABD produced a strong single band. The antibody against the cgABP260 ABD detected a single peptide band in smooth, skeletal, and cardiac muscle. In immunofluorescence microscopy of muscular tissues using these antibodies, the antibody against the gizzard filamin ABD only stained smooth muscle cells, and the antibody against the retina filamin ABD strongly stained endothelial cells of blood vessels and weakly stained cells in connective tissue. The antibody against the cgABP260 ABD stained the Z-lines and myotendinous junctions of breast muscle, the Z-lines and intercalated disks of cardiac muscle, and dense plaques of smooth muscle. These findings indicate that chicken gizzard filamin, retina filamin, and cgABP260 are, respectively, smooth muscle-type, non-muscle-type, and pan-muscle-type filamin isoforms. 相似文献