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991.
992.
Masaki Miyazaki Hidetoshi Nakamura Shotaro Chubachi Mamoru Sasaki Mizuha Haraguchi Shuichi Yoshida Keishi Tsuduki Toru Shirahata Saeko Takahashi Naoto Minematsu Hidefumi Koh Morio Nakamura Fumio Sakamaki Takeshi Terashima Koichi Sayama Paul W Jones Koichiro Asano Tomoko Betsuyaku 《Respiratory research》2014,15(1):13
Background
The chronic obstructive pulmonary disease (COPD) Assessment Test (CAT) is a concise health status measure for COPD. COPD patients have a variety of comorbidities, but little is known about their impact on quality of life. This study was designed to investigate comorbid factors that may contribute to high CAT scores.Methods
An observational study at Keio University and affiliated hospitals enrolled 336 COPD patients and 67 non-COPD subjects. Health status was assessed by the CAT, the St. Georges Respiratory Questionnaire (SGRQ), and all components of the Medical Outcomes Study Short-Form 36-Item (SF-36) version 2, which is a generic measure of health. Comorbidities were identified based on patients’ reports, physicians’ records, and questionnaires, including the Frequency Scale for the Symptoms of Gastro-esophageal reflux disease (GERD) and the Hospital Anxiety and Depression Scale. Dual X-ray absorptiometry measurements of bone mineral density were performed.Results
The CAT showed moderate-good correlations with the SGRQ and all components of the SF-36. The presence of GERD, depression, arrhythmia, and anxiety was significantly associated with a high CAT score in the COPD patients.Conclusions
Symptomatic COPD patients have a high prevalence of comorbidities. A high CAT score should alert the clinician to a higher likelihood of certain comorbidities such as GERD and depression, because these diseases may co-exist unrecognized.Trial registration
Clinical trial registered with UMIN (UMIN000003470). 相似文献993.
Fukushima T Arai T Ariga-Nedachi M Okajima H Ooi Y Iijima Y Sone M Cho Y Ando Y Kasahara K Ozoe A Yoshihara H Chida K Okada S Kopchick JJ Asano T Hakuno F Takahashi S 《Biochemical and biophysical research communications》2011,(3):767-773
Insulin receptor substrates (IRSs) are phosphorylated by activated insulin/insulin-like growth factor (IGF)-I receptor tyrosine kinases. Phosphotyrosyl IRSs are recognized by signaling molecules possessing src homology region 2 (SH2) domains, which mediate various insulin/IGF bioactivities. However, we have shown that IRSs are also associated with other proteins by a phosphotyrosine-independent mechanism. Here, we demonstrated that IRSs form high-molecular-mass complexes (we named these complexes IRSomes) with various proteins and we elucidated their possible roles. Blue native-polyacrylamide gel electrophoresis of cell lysates revealed IRSome formation. Some proteins associated with IRSs in IRS-isoform-, cell-type-, or stimulus-specific manners. Results of the in vitro tyrosine phosphorylation assay indicated that tyrosine phosphorylation of IRS-1 by insulin receptor was decreased when IRS-1 was contained in IRSomes prepared from 3T3-L1 adipocytes treated with TNF-α. Also, tyrosine phosphorylation of IRS-2 by IGF-I receptor was increased when IRS-2 was contained in IRSomes prepared from FRTL-5 thyrocytes treated with dibutyryl cAMP. These results demonstrated that cytokine/hormone-induced formation of IRSomes modulates availability of IRSs to receptor tyrosine kinases. 相似文献
994.
Shakor AB Taniguchi M Kitatani K Hashimoto M Asano S Hayashi A Nomura K Bielawski J Bielawska A Watanabe K Kobayashi T Igarashi Y Umehara H Takeya H Okazaki T 《The Journal of biological chemistry》2011,286(41):36053-36062
Transferrin (Tf) endocytosis and recycling are essential for iron uptake and the regulation of cell proliferation. Tf and Tf receptor (TfR) complexes are internalized via clathrin-coated pits composed of a variety of proteins and lipids and pass through early endosomes to recycling endosomes. We investigated the role of sphingomyelin (SM) synthases (SMS1 and SMS2) in clathrin-dependent trafficking of Tf and cell proliferation. We employed SM-deficient lymphoma cells that lacked SMSs and that failed to proliferate in response to Tf. Transfection of SMS1, but not SMS2, enabled these cells to incorporate SM into the plasma membrane, restoring Tf-mediated proliferation. SM-deficient cells showed a significant reduction in clathrin-dependent Tf uptake compared with the parental SM-producing cells. Both SMS1 gene transfection and exogenous short-chain SM treatment increased clathrin-dependent Tf uptake in SM-deficient cells, with the Tf being subsequently sorted to Rab11-positive recycling endosomes. We observed trafficking of the internalized Tf to late/endolysosomal compartments, and this was not dependent on the clathrin pathway in SM-deficient cells. Thus, SMS1-mediated SM synthesis directs Tf-TfR to undergo clathrin-dependent endocytosis and recycling, promoting the proliferation of lymphoma cells. 相似文献
995.
Abe Y Suwa Y Asano T Ueta YY Kobayashi N Ohshima N Shirasuna S Abdel-Ghani MA Oi M Kobayashi Y Miyoshi M Miyahara K Suzuki H 《Biology of reproduction》2011,84(2):363-368
The assisted reproductive techniques (ARTs) such as in vitro fertilization, embryo transfer, and cryopreservation of gametes have contributed considerably to the development of biomedical sciences in addition to improving infertility treatments in humans as well as the breeding of domestic animals. However, ARTs used in canine species have strictly limited utility when compared with other mammalian species, including humans. Although successful somatic cell cloning has been reported, artificial insemination by frozen semen to date is only available for the improved breeding and reproduction for companion and working dogs as well as guide dogs for the blind. We describe here the successful cryopreservation of embryos and subsequent embryo transfer in dogs. Canine embryos were collected from excised reproductive organs after artificial insemination and subsequently cryopreserved by a vitrification method. When the 4-cell to morula stage of cryopreserved embryos were nonsurgically transferred into the uteri of nine recipient bitches using a cystoscope, five recipients became pregnant and four of them delivered a total of seven pups. The cryopreservation of embryos in canine species will facilitate the transportation and storage of genetic materials and will aid in the elimination of vertically transmitted diseases in dogs. In addition, this technique will contribute to the improved breeding of companion and working dogs such as guide dogs, drug-detecting dogs, and quarantine dogs. 相似文献
996.
Yamamoto Y Harashima A Saito H Tsuneyama K Munesue S Motoyoshi S Han D Watanabe T Asano M Takasawa S Okamoto H Shimura S Karasawa T Yonekura H Yamamoto H 《Journal of immunology (Baltimore, Md. : 1950)》2011,186(5):3248-3257
Septic shock is a severe systemic response to bacterial infection. Receptor for advanced glycation end products (RAGE) plays a role in immune reactions to recognize specific molecular patterns as pathogen recognition receptors. However, the interaction between LPS, the bioactive component of bacterial cell walls, and RAGE is unclear. In this study, we found direct LPS binding to RAGE by a surface plasmon resonance assay, a plate competition assay, and flow cytometry. LPS increased TNF-α secretion from peritoneal macrophages and an NF-κB promoter-driven luciferase activity through RAGE. Blood neutrophils and monocytes expressed RAGE, and TLR2 was counterregulated in RAGE(-/-) mice. After LPS injection, RAGE(+/+) mice showed a higher mortality, higher serum levels of IL-6, TNF-α, high mobility group box 1, and endothelin-1, and severe lung and liver pathologies compared with RAGE(-/-) mice without significant differences in plasma LPS level. Administration of soluble RAGE significantly reduced the LPS-induced cytokine release and tissue damage and improved the LPS-induced lethality even in RAGE(-/-) as well as RAGE(+/+) mice. The results thus suggest that RAGE can associate with LPS and that RAGE system can regulate inflammatory responses. Soluble RAGE would be a therapeutic tool for LPS-induced septic shock. 相似文献
997.
Insulin Receptor Substrate-4 Binds to Slingshot-1 Phosphatase and Promotes Cofilin Dephosphorylation
Yuta Homma Shin-ichiro Kanno Kazutaka Sasaki Michiru Nishita Akira Yasui Tomoichiro Asano Kazumasa Ohashi Kensaku Mizuno 《The Journal of biological chemistry》2014,289(38):26302-26313
Cofilin plays an essential role in cell migration and morphogenesis by enhancing actin filament dynamics via its actin filament-severing activity. Slingshot-1 (SSH1) is a protein phosphatase that plays a crucial role in regulating actin dynamics by dephosphorylating and reactivating cofilin. In this study, we identified insulin receptor substrate (IRS)-4 as a novel SSH1-binding protein. Co-precipitation assays revealed the direct endogenous binding of IRS4 to SSH1. IRS4, but not IRS1 or IRS2, was bound to SSH1. IRS4 was bound to SSH1 mainly through the unique region (amino acids 335–400) adjacent to the C terminus of the phosphotyrosine-binding domain of IRS4. The N-terminal A, B, and phosphatase domains of SSH1 were bound to IRS4 independently. Whereas in vitro phosphatase assays revealed that IRS4 does not directly affect the cofilin phosphatase activity of SSH1, knockdown of IRS4 increased cofilin phosphorylation in cultured cells. Knockdown of IRS4 decreased phosphatidylinositol 3-kinase (PI3K) activity, and treatment with an inhibitor of PI3K increased cofilin phosphorylation. Akt preferentially phosphorylated SSH1 at Thr-826, but expression of a non-phosphorylatable T826A mutant of SSH1 did not affect insulin-induced cofilin dephosphorylation, and an inhibitor of Akt did not increase cofilin phosphorylation. These results suggest that IRS4 promotes cofilin dephosphorylation through sequential activation of PI3K and SSH1 but not through Akt. In addition, IRS4 co-localized with SSH1 in F-actin-rich membrane protrusions in insulin-stimulated cells, which suggests that the association of IRS4 with SSH1 contributes to localized activation of cofilin in membrane protrusions. 相似文献
998.
Hildson Dornelas Angelo da Silva Alex Paulino da Silva Helker Albuquerque da Silva Nadja Maria Jorge Asano Maria de Mascena Diniz Maia Paulo Roberto Eleutério de Souza 《Molecular biology reports》2014,41(4):2493-2500
The pathogenesis of systemic lupus erythematosus (SLE) is complex, with several susceptibility genes and environmental factors involved in its development and clinical manifestation. Currently, there is a great amount of interest in the identification of biomarkers, as cytokines, that can quantify the susceptibility of SLE, the risk of future organ involvement, and association of their changes with disease activity. To investigate the associations between polymorphisms in the gene of Interferon gamma (IFN-γ) and in the promoter of the Interleukin-10 (IL-10) gene and SLE. The polymorphisms +874 T/A (rs2430561) in the IFN-γ gene and ?1082G/A (rs1800896) in the IL-10 promoter were determined in 99 SLE patients and 100 healthy controls among women Brazilian using the refractory mutation system polymerase chain reaction method. Disease activity was assessed using the SLE activity index. There were significant differences in the distribution of the genotype T/A in IFN-γ gene polymorphism (+874) (χ 2 = 7.168; P = 0.0074) and the genotype G/A in IL-10 promoter polymorphism (?1082) (χ 2 = 4.654; P = 0.0310) between the SLE and control groups. However, no association was observed between clinical features and the polymorphisms studied. This study presents preliminary evidence for association between IL-10 and IFN-γ polymorphism and SLE susceptibility, but not with clinical features in a Northeast population from Brazil. 相似文献
999.
We designed four fluorinated Phe‐incorporated ascidiacyclamide ([Phe]ASC) analogs, (cyclo(?Xxx1‐oxazoline2‐d ‐Val3‐thiazole4‐Ile5‐oxazoline6‐d ‐Val7‐thiazole8‐)), [(4‐F)Phe]ASC (Xxx1: 4‐fluorophenylalanine), [(3,5‐F2)Phe]ASC (Xxx1: 3,5‐difluorophenylalanine), [(3,4,5‐F3)Phe]ASC (Xxx1: 3,4,5‐trifluorophenylalanine) and [(F5)Phe]ASC (Xxx1: pentafluorophenylalanine), to modulate the π‐electron density of the aromatic ring of the Phe residue. X‐ray diffraction analysis, 1H NMR and CD spectra all suggested that the interactions between the benzene ring of the Xxx1 residue and the alkyl groups of oxazoline2 contribute to the stability of the folded structure of these analogs. Substituting fluorines for the hydrogens progressively weakened those interactions through reducing the π‐electron density, thereby mediating transformation from the folded to square structure. As a result, [(F5)Phe]ASC preferred the square form more than the other analogs did. Also contributing to the preference for the square form may be the hindrance of the rotation around the Cα–Cβ bond by the two ortho‐fluoro substituents of [(F5)Phe]ASC. These findings demonstrate that the structure of ASC can be modulated by using fluorine as an electron‐withdrawing group. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
1000.
Masao Takano Emi Ogawa Tsubasa Saitou Yuko Yamaguchi Yuzo Asano Tadao Serikawa Takashi Kuramoto 《Experimental Animals》2014,63(3):269-275
IS-Tlk/Kyo, a mutant derived from IS/Kyo strain,
exhibits a kinked and/or short tail, in addition to the congenital lumbar vertebral
anomaly. Homozygotes of Tlk dominant gene are known to die during
embryonic development. We previously reported the morphological features of the skeleton
in IS/Kyo and IS-Tlk/Kyo fetuses and of the heart in
IS/Kyo fetuses [19]. This study was conducted to
clarify the morphological features of the skeleton in both adult rats and of the heart in
adult IS/Kyo rats. Ventricular septal defect (VSD) was observed in 3 out of 10 IS/Kyo
rats. Neither splitting of lumbar vertebra and supernumerary rib (in both strains) nor
fused or absent caudal cartilage (in IS-Tlk/Kyo strain) was detected in
adult rats. Fusion of lumbar vertebrae was observed in almost all specimens together with
lumbarization of sacral vertebrae in a few specimens in both adult rats as well as fusion
of sacral and caudal vertebrae only in adult IS-Tlk/Kyo rats. In
addition, a severe reduction in the ossified sacral and caudal vertebrae was noted in
adult IS-Tlk/Kyo rats (mean number: 20.6) and IS/Kyo
rats (31.8), and the difference was similar to that in the length of sacral and caudal
vertebrae. These results suggest that the Tlk gene may be involved in
both the congenital and acquired abnormal formation of the lower vertebral centra as well
as the persistent occurrence of VSD by the background gene in IS/Kyo strain. 相似文献