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991.
Hitomi Yamada Toshio Tsushima Hitomi Murakami Yasuko Uchigata Yasuhiko Iwamoto 《Experimental diabetes research》2002,3(2):131-144
Hyperinsulinemia has been shown to be
associated with diabetic angiopathy. Migration
and proliferation of vascular smooth muscle
cells (VSMC) are the processes required for the
development of atherosclerosis. In this study,
we attempted to determine whether insulin
affects mitogenic signaling induced by plateletderived
growth factor (PDGF) in a rat VSMC
cell line (A10 cells). PDGF stimulated DNA
synthesis which was totally dependent on Ras,
because transfection of dominant negative Ras
resulted in complete loss of PDGF-stimulated
DNA synthesis. Initiation of DNA synthesis
was preceded by activation of Raf-1, MEK and
MAP kinases (Erk 1 and Erk2). Treatment of
the cells with PD98059, an inhibitor of MAPK
kinase (MEK) attenuated but did not abolish
PDGF-stimulated DNA synthesis, suggesting
that MAPK is required but not essential for
DNA synthesis. PDGF also stimulated phosphorylation
of protein kinase B (Akt/PKB) and
p70 S6Kinase (p70S6K) in a wortmannin-sensitive
manner. Rapamycin, an inhibitor of
p70S6K, markedly suppressed DNA synthesis.
Low concentrations of insulin (1-10 nmol/l)
alone showed little mitogenic activity and no
significant effect on MAPK activity. However,
the presence of insulin enhanced both DNA
synthesis and MAPK activation by PDGF. The
enhancing effect of insulin was not seen in cells
treated with PD98059. Insulin was without
effect on PDGF-stimulated activations of protein kinase B (Akt/PKB) and p70S6K. We conclude
that insulin, at pathophysiologically relevant
concentrations, potentiates the PDGFstimulated
DNA synthesis, at least in part, by
potentiating activation of the MAPK cascade.
These results are consistent with the notion
that hyperinsulinemia is a risk factor for the
development of atherosclerosis. 相似文献
992.
Hayato Harima Michihito Sasaki Yasuko Orba Kosuke Okuya Yongjin Qiu Christida E. Wastika Katendi Changula Masahiro Kajihara Edgar Simulundu Tomoyuki Yamaguchi Yoshiki Eto Akina Mori-Kajihara Akihiko Sato Satoshi Taniguchi Ayato Takada Masayuki Saijo Bernard M. Hangombe Hirofumi Sawa 《PLoS neglected tropical diseases》2021,15(9)
BackgroundPteropine orthoreovirus (PRV) is an emerging bat-borne zoonotic virus that causes severe respiratory illness in humans. Although PRVs have been identified in fruit bats and humans in Australia and Asia, little is known about the prevalence of PRV infection in Africa. Therefore, this study performed an PRV surveillance in fruit bats in Zambia.MethodsEgyptian fruit bats (Rousettus aegyptiacus, n = 47) and straw-colored fruit bats (Eidolon helvum, n = 33) captured in Zambia in 2017–2018 were screened for PRV infection using RT-PCR and serum neutralization tests. The complete genome sequence of an isolated PRV strain was determined by next generation sequencing and subjected to BLAST and phylogenetic analyses. Replication capacity and pathogenicity of the strain were investigated using Vero E6 cell cultures and BALB/c mice, respectively.ResultsAn PRV strain, tentatively named Nachunsulwe-57, was isolated from one Egyptian fruit bat. Serological assays demonstrated that 98% of sera (69/70) collected from Egyptian fruit bats (n = 37) and straw-colored fruit bats (n = 33) had neutralizing antibodies against PRV. Genetic analyses revealed that all 10 genome segments of Nachunsulwe-57 were closely related to a bat-derived Kasama strain found in Uganda. Nachunsulwe-57 showed less efficiency in viral growth and lower pathogenicity in mice than another PRV strain, Miyazaki-Bali/2007, isolated from a patient.ConclusionsA high proportion of Egyptian fruit bats and straw-colored fruit bats were found to be seropositive to PRV in Zambia. Importantly, a new PRV strain (Nachunsulwe-57) was isolated from an Egyptian fruit bat in Zambia, which had relatively weak pathogenicity in mice. Taken together, our findings provide new epidemiological insights about PRV infection in bats and indicate the first isolation of an PRV strain that may have low pathogenicity to humans. 相似文献
993.
994.
Brooks KJ Hargreaves I Bhakoo K Sellwood M O'Brien F Noone M Sakata Y Cady E Wylezinska M Thornton J Ordidge R Nguyen Q Clemence M Wyatt J Bates TE 《Neurochemical research》2002,27(12):1599-1604
The effects of normothermia and delayed hypothermia on the levels of N-acetylaspartate (NAA), reduced glutathione (GSH) and the activities of mitochondrial complex I, II-III, IV and citrate synthase were measured in brain homogenates obtained from anaesthetized neonatal pigs following transient in vivo hypoxia-ischaemia. In the normothermic animals there was a significant decrease in complex I activity and in the levels of GSH and NAA when compared to the controls. Delayed hypothermia preserved NAA and GSH at control levels and enhanced the rate of complex II-III activity. There was correlation (R = 0.79) between GSH and NAA levels when data from all three experimental groups were analyzed. Citrate synthase activity was not significantly different in the three groups, indicating maintenance of mitochondrial integrity. These data suggest that delayed hypothermia affords protection of integrated mitochondrial function in the neonatal brain following transient hypoxia-ischaemia. 相似文献
995.
Michiko Takahashi Tomoko Nozoye Nobuyuki Kitajima Naoki Fukuda Akiko Hokura Yasuko Terada Izumi Nakai Yasuhiro Ishimaru Takanori Kobayashi Hiromi Nakanishi Naoko K Nishizawa 《Plant and Soil》2009,325(1-2):39-51
To investigate the flow of the metal nutrients iron (Fe), zinc (Zn), manganese (Mn), and copper (Cu) during rice seed germination, we performed microarray analysis to examine the expression of genes involved in metal transport. Many kinds of metal transporter genes were strongly expressed and their expression levels changed during rice seed germination. We found that metal transporter genes such as ZIP family has tendency to decrease in their expressions during seed germination. Furthermore, imaging of the distribution of elements (Fe, Mn, Zn, and Cu) was carried out using Synchrotron-based X-ray microfluorescence at the Super Photon ring-8 GeV (SPring-8) facility. The change in the distribution of each element in the seeds following germination was observed by in vivo monitoring. Iron, Mn, Zn, and Cu accumulated in the endosperm and embryos of rice seeds, and their distribution changed during rice seed germination. The change in the patterns of mineral localization during germination was different among the elements observed. 相似文献
996.
Production of cholera toxin (CT) in AKI medium and conservation of CT gene (ctx) of 49 strains of Vibrio cholerae O1 were compared by reversed passive latex agglutination (RPLA) and polymerase chain reaction (PCR). The production of CT agreed with conservation of the ctx in 48 out of the 49 strains. Ten strains were positive, and 38 strains were negative by both methods. Only one strain was negative in RPLA and positive in PCR. This suggested that the combination of AKI-SW and RPLA is comparable to PCR to identify CT-producing V. cholerae O1. 相似文献
997.
Solution structure of a BolA-like protein from Mus musculus 总被引:2,自引:0,他引:2
Kasai T Inoue M Koshiba S Yabuki T Aoki M Nunokawa E Seki E Matsuda T Matsuda N Tomo Y Shirouzu M Terada T Obayashi N Hamana H Shinya N Tatsuguchi A Yasuda S Yoshida M Hirota H Matsuo Y Tani K Suzuki H Arakawa T Carninci P Kawai J Hayashizaki Y Kigawa T Yokoyama S 《Protein science : a publication of the Protein Society》2004,13(2):545-548
The BolA-like proteins are widely conserved from prokaryotes to eukaryotes. The BolA-like proteins seem to be involved in cell proliferation or cell-cycle regulation, but the molecular function is still unknown. Here we determined the structure of a mouse BolA-like protein. The overall topology is alphabetabetaalphaalphabetaalpha, in which beta(1) and beta(2) are antiparallel, and beta(3) is parallel to beta(2). This fold is similar to the class II KH fold, except for the absence of the GXXG loop, which is well conserved in the KH fold. The conserved residues in the BolA-like proteins are assembled on the one side of the protein. 相似文献
998.
Kenzo Kumamoto Tadao Matsuura Takashi Amagai Mitsuhiro Kawata 《Cell and tissue research》1995,280(1):1-10
The localization of an endogenous 14-kDa -galactoside-binding lectin (galectin) and its pattern of gene expression were examined in normal human skin by light- and electron microscopy. Under the light microscope, immunostaining of 14-kDa galectin was observed in the cell membrane of cells in the basal and spinous layers of the epidermis. Galectin was also found in the Langerhans cells, as shown by double labeling using anti-14-kDa galectin and anti-CD1a antibodies. In the dermis, immunostaining for the 14-kDa galectin was positive in the extracellular matrix and fibroblasts. At the electron-microscopic level of resolution, galectin was located primarily along the plasma membrane of keratinocytes, and in both the cytoplasm and nucleus of Langerhans cells in the epidermis, whereas in the dermis it was detected in the extracellular matrix and in both the nucleus and cytoplasm of fibroblasts. The gene expression of 14-kDa galectin was visualized by the HRP-staining method following in situ hybridization techniques. The expression was detected in the cytoplasm of cells in the basal and spinous layers of the epidermis; whereas, in the dermis, it was detected in the cytoplasm of fibroblasts. Moreover, SDS-polyacrylamide gel electrophoresis and lectin-blot analysis revealed that this galectin bound to glycoproteins of approximately 17, 62, and 72 kDa in the epidermis and to those of 29, 54, and 220 kDa in the dermis. The present study indicates that 1) normal human skin produces the -galactoside-binding 14-kDa galectin, and 2) this galectin is located in both the epidermis, particularly in the keratinocytes and Langerhans cells, and in the dermis. These results suggest that galectin is important for cell-cell contact and/or adhesion in the epidermis and for cell-extracellular matrix interaction in the dermis. 相似文献
999.
Maeda Y Hatta M Takada A Watanabe T Goto H Neumann G Kawaoka Y 《Journal of virology》2005,79(11):6674-6679
Influenza and human parainfluenza virus infections are of both medical and economical importance. Currently, inactivated vaccines provide suboptimal protection against influenza, and vaccines for human parainfluenza virus infection are not available, underscoring the need for new vaccines against these respiratory diseases. Furthermore, to reduce the burden of vaccination, the development of multivalent vaccines is highly desirable. Thus, to devise a single vaccine that would elicit immune responses against both influenza and parainfluenza viruses, we used reverse genetics to generate an influenza A virus that possesses the coding region for the hemagglutinin/neuraminidase ectodomain of parainfluenza virus instead of the influenza virus neuraminidase. The recombinant virus grew efficiently in eggs but was attenuated in mice. When intranasally immunized with the recombinant vaccine, all mice developed antibodies against both influenza and parainfluenza viruses and survived an otherwise lethal challenge with either of these viruses. This live bivalent vaccine has obvious advantages over combination vaccines, and its method of generation could, in principle, be applied in the development of a "cocktail" vaccine with efficacy against several different infectious diseases. 相似文献
1000.
Saito K Arata S Hosono T Sano Y Takahashi K Choi-Miura NH Nakano Y Tobe T Tomita M 《Biochimica et biophysica acta》2006,1761(7):709-716
Adiponectin is an adipose tissue-specific secretory protein known to be an insulin-sensitizing protein. In this study, we generated adiponectin sense and antisense transgenic (Tg) mice to investigate whether adiponectin plays a role in the regulation of energy homeostasis during the growth stage. Spontaneous motor activity of antisense Tg mice were markedly reduced during fasting, particularly in young female mice, compared with wild type (Wt) and sense Tg mice. Furthermore, both body weight and adipose tissue mass of the antisense female Tg mice drastically reduced during fasting. To examine the relationship between the collapse of abdominal white adipose tissue (WAT) and serum adiponectin level, we measured the expression of genes related to energy expenditure, such as uncoupling protein (UCP). Notably, the mRNA of UCP1 in the WAT of antisense Tg female mice was markedly less than that of Wt mice and the UCP1 mRNA was strongly increased during fasting. These findings suggest that the serum adiponectin is important to maintaining energy homeostasis under energy shortage conditions, such as over female pubertal development. 相似文献