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961.
Hiroshi Yao Takashi Matsumoto Makoto Hirano Toshihide Kuroki Tetsuyuki Tsutsumi Hideyuki Uchimura Kaoru Nakamura Tatsuo Nakahara Masatoshi Fujishima 《Neurochemical research》1989,14(1):75-79
This study attempted to investigate the possible involvement of the brain stem noradrenergic system in the development of hypertension in spontaneously hypertensive rats. Steady-state norepinephrine, dopamine, serotonin and 5-hydroxyindoleacetic acid concentrations and norepinephrine turnover were determined in the individual brain stem nuclei using high performance liquid chromatography with electrochemical detection. Decreased norepinephrine contents in the nucleus tractus solitarii in spontaneously hypertensive rats compared with Wistar-Kyoto rats at the age of 4, 8, and 16 weeks were demonstrated. In later stages (8 and 16 weeks), increased norepinephrine levels were observed in the nucleus reticularis gigantocellularis, the A1 and A5 areas. Norepinephrine turnover was not different between spontaneously hypertensive rats and Wistar-Kyoto rats in the nucleus tractus solitarii at the age of 4 and 16 weeks and increased in the nucleus reticularis gigantocellularis of spontaneously hypertensive rats at 16 weeks. Our results indicate that altered norepinephrine metabolism in the specific brain stem nuclei, especially the consistently decreased norepinephrine in the nucleus tractus solitarii of spontaneously hypertensive rats, contribute to the development of genetic hypertension. 相似文献
962.
Yukiyoshi Shirasaka Dr. Masatoshi Ito Hideo Tsuda Hideyuki Shiraishi Katsuhiko Oguro Kozoh Mutoh Haruki Mikawa 《Neurochemical research》1990,15(9):869-874
Benzodiazepine receptors and subtypes were examined in El mice and normal ddY mice with a quantitative autoradiographic technique. Specific [3H]flunitrazepam binding in stimulated El mice, which had experienced repeated convulsions, was significantly lower in the cortex and hippocampus than in ddY mice and unstimulated El mice. In the amygdala, specific [3H]flunitrazepam binding in stimulated El mice was lower than in ddY mice. There was a tendency for the [3H]flunitrazepam binding in these regions in unstimulated El mice to be intermediate between that in stimulated El mice and that in ddY mice, but there was no significant difference between unstimulated El mice and ddY mice. [3H]Flunitrazepam binding displaced by CL218,872 was significantly lower in the cortex of stimulated El mice than in that of the other two groups, and in the hippocampus of stimulated than of unstimulated El mice. These data suggest that the decrease in [3H]flunitrazepam binding in stimulated El mice may be due mainly to that of type 1 receptor and may be the result of repeated convulsions. 相似文献
963.
Yuhsi Matuo Nozomu Nishi Hideyuki Tanaka Ikuharu Sasaki John T. Issacs Fumio Wada 《In vitro cellular & developmental biology. Plant》1988,24(10):1053-1056
Summary AT-3 cells, one of anaplastic cell lines established from the Dunning prostatic carcinoma of rats, were able to grow under
serum-free conditions in a state of suspension detached from a substratum. Radioimmunoassays using monoclonal antibody against
rat insulin-like growth factor II (IGF-II) revealed the presence of IGF-II-related peptide in acid-ethanol extracts extracsts
of lyophilized serum-free media conditioned by AT-3 cell. The peptide contents in the culture media increased with increase
in cell number; 71 ng at 3.0 × 106 cells and 449 ng at 4.6 × 107 cells. IGF-II-related peptide was hardly detectable in acid-ethanol extracts of AT-3 cells harvested after 13-days culture.
These results indicate that AT-3 cells produce IGF-II-related peptide ana may release it into the culture media.
Editor's statement One or more members of the insulin-like growth factor family have been established previously as mitogen
for isolated prostate cells. This report suggests that IGF-II member of the family may be involved in autocrine support of
cells from highly malignant prostate tumors. 相似文献
964.
Hideyuki Yamada Kiyoshi Tatsumi Yuichi Kawazoe Hidetoshi Yoshimura 《Archives of biochemistry and biophysics》1984,232(1):234-239
After methyl 5-nitro-2-furoate was incubated with milk xanthine oxidase, three reduction products were isolated from the incubation mixture. Among them, two reduction products were new types of nitrofuran metabolites, i.e., metabolites 1 and 2 were identified as the dihydroxyhydrazine derivative (1,2-dihydroxy-1,2-di(5-methoxycarbonyl-2-furyl) hydrazine) and the hydroxylaminofuran derivative (methyl 5-hydroxylamino-2-furoate), respectively. Metabolite 3 was also identified as the aminofuran derivative (methyl 5-amino-2-furoate) by comparison with a synthetic sample. 相似文献
965.
Hideyuki Maeda 《Free radical research》2016,50(7):720-731
Non-alcoholic fatty liver disease (NAFLD) is prevalent in patients with sleep apnea syndrome (SAS). Intermittent hypoxia (IH) and a high-fat diet (HFD) reproduce SAS and NAFLD, respectively, in rodents. In this study, rats were fed either an HFD or a standard diet (SD) for 2 weeks, and breathed either IH air or normoxic air for 4 days (early phase) or 6 weeks (late phase), with the same diets maintained during the exposure. HFD increased hepatic lipid accumulation, as detected by oil-red staining and triglyceride content. However, IH exposure reversed the hepatic steatosis at the late phase in these HFD-rats. IH exposure also increased hepatic expression of HO-1 and iron-binding protein ferritin-1 at the late phase, in association with increase in serum iron, bilirubin, and hepatic levels of lipid peroxides, such as 4-hydroxy-2-nonenal (HNE). IH exposure increased serum levels of hemoglobin (Hb) at the early phase and immunofluorescence of Hb and HO-1 in CD68-positive Kupffer cells (KCs) at the late phase. These findings support that IH induces erythrocytosis, erythro-phagocytosis, and generation of Hb in the KCs. The Hb promotes HO-1 expression in KCs, thereby produces iron, bilirubin, and carbon monoxide (CO). The iron would be either sequestrated by ferritin-1, transferred to the bone marrow for erythropoiesis, or would produce hydroxyradicals and HNE in the liver of rats fed an HFD. HNE might also contribute to the upregulation of HO-1, transferrin-1, and IκB, thereby limiting hepatic steatosis and inflammation via inhibition of nuclear factor κB (NFκB) activation. 相似文献
966.
Feng Ling Rong Niu Hideyuki Hatakeyama Yu-ichi Goto Takehiko Shibata Minoru Yoshida 《Molecular biology of the cell》2016,27(10):1684-1693
Mitochondria that contain a mixture of mutant and wild-type mitochondrial (mt) DNA copies are heteroplasmic. In humans, homoplasmy is restored during early oogenesis and reprogramming of somatic cells, but the mechanism of mt-allele segregation remains unknown. In budding yeast, homoplasmy is restored by head-to-tail concatemer formation in mother cells by reactive oxygen species (ROS)–induced rolling-circle replication and selective transmission of concatemers to daughter cells, but this mechanism is not obvious in higher eukaryotes. Here, using heteroplasmic m.3243A > G primary fibroblast cells derived from MELAS patients treated with hydrogen peroxide (H2O2), we show that an optimal ROS level promotes mt-allele segregation toward wild-type and mutant mtDNA homoplasmy. Enhanced ROS level reduced the amount of intact mtDNA replication templates but increased linear tandem multimers linked by head-to-tail unit-sized mtDNA (mtDNA concatemers). ROS-triggered mt-allele segregation correlated with mtDNA-concatemer production and enabled transmission of multiple identical mt-genome copies as a single unit. Our results support a mechanism by which mt-allele segregation toward mt-homoplasmy is mediated by concatemers. 相似文献
967.
968.
Etsuko Iio Kentaro Matsuura Nao Nishida Shinya Maekawa Nobuyuki Enomoto Mina Nakagawa Naoya Sakamoto Hiroshi Yatsuhashi Masayuki Kurosaki Namiki Izumi Yoichi Hiasa Naohiko Masaki Tatsuya Ide Keisuke Hino Akihiro Tamori Masao Honda Shuichi Kaneko Satoshi Mochida Hideyuki Nomura Shuhei Nishiguchi Chiaki Okuse Yoshito Itoh Hitoshi Yoshiji Isao Sakaida Kazuhide Yamamoto Hisayoshi Watanabe Shuhei Hige Akihiro Matsumoto Eiji Tanaka Katsushi Tokunaga Yasuhito Tanaka 《Human genetics》2015,134(3):279-289
969.
Hideyuki Suzuki Professor Chiaki Yamada Kyoko Kijima Sayaka Ishihara Kei Wada Keiichi Fukuyama Hidehiko Kumagai 《Biotechnology journal》2010,5(8):829-837
Semisynthetic cephalosporins, the best-selling antibiotics worldwide, are derived from 7-aminocephalosporanic acid (7-ACA). Currently, in the pharmaceutical industrie, 7-ACA is mainly produced from cephalosporin C by sequential application of D -amino acid oxidase and cephalosporin acylase. Here we study the potential of industrially amenable enzyme γ-glutamyltranspeptidase from Bacillus subtilis for 7-ACA production, since the wild-type γ-glutamyltranspeptidase of B. subtilis has inherent glutaryl-7-aminocephalosporanic acid acylase activity with a kcat value of 0.0485 s-1. Its activity has been enhanced by site directed and random mutagenesis. The kcat/Km value was increased to 3.41 s-1 mM-1 for a E423Y/E442Q/D445N mutant enzyme and the kcat value was increased to 0.508 s-1 for a D445G mutant enzyme. Consequently, the catalytic efficiency and the turnover rate were improved up to about 1000-fold and 10-fold, compared with the wildtype γ-glutamyltranspeptidase of B. subtilis. 相似文献
970.
Hidetsugu Nakazato Hideyuki Takeshima Takayoshi Kishino Emi Kubo Naoko Hattori Takeshi Nakajima Satoshi Yamashita Hiroyasu Igaki Yuji Tachimori Yukio Kuniyoshi Toshikazu Ushijima 《PloS one》2016,11(1)
The SWI/SNF chromatin remodeling complex is frequently inactivated by somatic mutations of its various components in various types of cancers, and also by aberrant DNA methylation. However, its somatic mutations and aberrant methylation in esophageal squamous cell carcinomas (ESCCs) have not been fully analyzed. In this study, we aimed to clarify in ESCC, what components of the SWI/SNF complex have somatic mutations and aberrant methylation, and when somatic mutations of the SWI/SNF complex occur. Deep sequencing of components of the SWI/SNF complex using a bench-top next generation sequencer revealed that eight of 92 ESCCs (8.7%) had 11 somatic mutations of 7 genes, ARID1A, ARID2, ATRX, PBRM1, SMARCA4, SMARCAL1, and SMARCC1. The SMARCA4 mutations were located in the Forkhead (85Ser>Leu) and SNF2 family N-terminal (882Glu>Lys) domains. The PBRM1 mutations were located in a bromodomain (80Asn>Ser) and an HMG-box domain (1,377Glu>Lys). For most mutations, their mutant allele frequency was 31–77% (mean 61%) of the fraction of cancer cells in the same samples, indicating that most of the cancer cells in individual ESCC samples had the SWI/SNF mutations on one allele, when present. In addition, a BeadChip array analysis revealed that a component of the SWI/SNF complex, ACTL6B, had aberrant methylation at its promoter CpG island in 18 of 52 ESCCs (34.6%). These results showed that genetic and epigenetic alterations of the SWI/SNF complex are present in ESCCs, and suggested that genetic alterations are induced at an early stage of esophageal squamous cell carcinogenesis. 相似文献