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61.
All five examined strains ofCoprinus cinereus could be clearly discriminated from the strains of five otherCoprinus species by RAPD patterns with 12 of 13 primers. Also one specimen of unknownCoprinus strain was identified to beC. cinereus by this method. The RAPD patterns were similar among the strains in the same species; many common DNA fragments were recognized
as well as some strain-specific DNA fragments. Thus all seven strains ofC. cinereus and all four strains ofC. angulatus examined could be distinguished individually. Diakryotic strains showed the combined RAPD patterns of the two monokaryotic
strains constituting the dikaryon. The combined RAPD markers observed in the dikaryons were segregated in their basidiospore
progeny. All 18 randomly picked progeny showed different combinations of RAPD markers from the parental strains. 相似文献
62.
Yokoyama Mineyuki; Inomata Shinji; Seto Susumu; Yanagi Mitsuo 《Plant & cell physiology》1990,31(4):551-555
The effects of sugars on the glucosylation of exogenous hydroquinone(HQ) was investigated by supplying individual sugars simultaneouslywith HQ to a suspension culture of Catharanthus roseus cells.The production of arbutin was enhanced as much as 2- to 3-foldby sucrose or glucose at concentrations of up to 6%, with theenhancement being directly dependent on the concentration ofthe sugar. The exogenously added sugar was not metabolized andremained unchanged. Sorbitol also promoted the production ofarbutin in a similar manner. Sucrose improved the viability of cells and, in cultures suppliedwith sucrose and HQ, the activity of UDP-glucose: hydroquinoneglucosyltransferase increased over a much longer period of timethan that in control cultures supplemented with HQ only. (Received December 11, 1989; Accepted March 26, 1990) 相似文献
63.
While PCTAIRE1/PCTK1/Cdk16 is overexpressed in malignant cells and is crucial in tumorigenesis, its function in apoptosis remains unclear. Here we investigated the role of PCTAIRE1 in apoptosis, especially in the extrinsic cell death pathway. Gene-knockdown of PCTAIRE1 sensitized prostate cancer PPC1 and Du145 cells, and breast cancer MDA-MB-468 cells to TNF-family cytokines, including TNF-related apoptosis-inducing ligand (TRAIL). Meanwhile, PCTAIRE1-knockdown did not sensitize non-malignant cells, including diploid fibroblasts IMR-90 and the immortalized prostate epithelial cell line 267B1. PCTAIRE1-knockdown did not up-regulate death receptor expression on the cell surface or affect caspase-8, FADD and FLIP expression levels. PCTAIRE1-knockdown did promote caspase-8 cleavage and RIPK1 degradation, while RIPK1 mRNA knockdown sensitized PPC1 cells to TNF-family cytokines. Furthermore, the kinase inhibitor SNS-032, which inhibits PCTAIRE1 kinase activity, sensitized PPC1 cells to TRAIL-induced apoptosis. Together these results suggest that PCTAIRE1 contributes to the resistance of cancer cell lines to apoptosis induced by TNF-family cytokines, which implies that PCTAIRE1 inhibitors could have synergistic effects with TNF-family cytokines for cytodestruction of cancer cells. 相似文献
64.
Glucose Homeostatic Law: Insulin Clearance Predicts the Progression of Glucose Intolerance in Humans
Kaoru Ohashi Hisako Komada Shinsuke Uda Hiroyuki Kubota Toshinao Iwaki Hiroki Fukuzawa Yasunori Komori Masashi Fujii Yu Toyoshima Kazuhiko Sakaguchi Wataru Ogawa Shinya Kuroda 《PloS one》2015,10(12)
Homeostatic control of blood glucose is regulated by a complex feedback loop between glucose and insulin, of which failure leads to diabetes mellitus. However, physiological and pathological nature of the feedback loop is not fully understood. We made a mathematical model of the feedback loop between glucose and insulin using time course of blood glucose and insulin during consecutive hyperglycemic and hyperinsulinemic-euglycemic clamps in 113 subjects with variety of glucose tolerance including normal glucose tolerance (NGT), impaired glucose tolerance (IGT) and type 2 diabetes mellitus (T2DM). We analyzed the correlation of the parameters in the model with the progression of glucose intolerance and the conserved relationship between parameters. The model parameters of insulin sensitivity and insulin secretion significantly declined from NGT to IGT, and from IGT to T2DM, respectively, consistent with previous clinical observations. Importantly, insulin clearance, an insulin degradation rate, significantly declined from NGT, IGT to T2DM along the progression of glucose intolerance in the mathematical model. Insulin clearance was positively correlated with a product of insulin sensitivity and secretion assessed by the clamp analysis or determined with the mathematical model. Insulin clearance was correlated negatively with postprandial glucose at 2h after oral glucose tolerance test. We also inferred a square-law between the rate constant of insulin clearance and a product of rate constants of insulin sensitivity and secretion in the model, which is also conserved among NGT, IGT and T2DM subjects. Insulin clearance shows a conserved relationship with the capacity of glucose disposal among the NGT, IGT and T2DM subjects. The decrease of insulin clearance predicts the progression of glucose intolerance. 相似文献
65.
Kazuhiko Tsuruya Hisako Yoshida Naoki Haruyama Kiichiro Fujisaki Hideki Hirakata Takanari Kitazono 《PloS one》2015,10(12)
Background & Objectives
It is well known that cognitive impairment in patients with chronic kidney disease (CKD) is characterized by executive dysfunction, rather than memory dysfunction, although the precise mechanism of this remains to be elucidated. The purpose of the present study is to examine the correlation between gray matter volume (GMV) and executive function in CKD patients.Design, Setting, Participants, Measurements
This cross-sectional study recruited 95 patients with non-dialysis-dependent CKD (NDD-CKD) with no history of cerebrovascular disease, who underwent brain magnetic resonance imaging (MRI) and Trail Making Test (TMT) in the VCOHP Study. The subjects underwent brain MRI and TMT part A (TMT-A) and part B (TMT-B). The segmentation algorithm from Statistical Parametric Mapping 8 software was applied to every T1-weighted MRI scan to extract tissue maps corresponding to gray matter, white matter, and cerebrospinal fluid. GMV was normalized by dividing by the total intracranial volume, calculated by adding GMV, white matter volume, and cerebrospinal fluid space volume. Then, normalized whole-brain GMV was divided into four categories of brain lobes; frontal, parietal, temporal, and occipital. We assessed the correlation between normalized GMV and TMT using multivariable regression analysis.Results
Normalized whole-brain GMV was significantly inversely correlated to the scores of TMT-A, TMT-B, and ΔTMT (TMT-B minus TMT-A). These correlations remained significant even after adjusting for relevant confounding factors. Normalized frontal and temporal GMV, but not parietal and occipital GMV, were significantly inversely correlated with TMT-A, TMT-B, and ΔTMT using multivariable regression analysis.Conclusions
The present study demonstrates the correlation between normalized GMV, especially in the frontal and temporal lobes, and executive function, suggesting that fronto-temporal gray matter atrophy might contribute to executive dysfunction in NDD-CKD. 相似文献66.
Yusuke Kawazoe Mutsumi Miyauchi Atsuhiro Nagasaki Hisako Furusho Syunryo Yanagisawa Chea Chanbora Toshihiro Inubushi Hideyuki Hyogo Takashi Nakamoto Keiko Suzuki Sawako Moriwaki Susumu Tazuma Shumpei Niida Takashi Takata 《PloS one》2015,10(9)
Background
Cholestatic liver diseases exhibit higher levels of serum γ-glutamyl transpeptidase (GGT) and incidence of secondary osteoporosis. GGT has been identified as a novel bone-resorbing factor that stimulates osteoclast formation. The aim of this study was to elucidate the interaction of elevated GGT levels and cholestatic liver disease-induced bone loss.Methods
Wistar rats were divided into three groups: sham-operated control (SO) rats, bile duct ligation (BDL) rats, and anti-GGT antibody-treated BDL rats (AGT). Serum GGT level was measured. Bone mineral density (BMD) was analyzed by dual-energy X-ray absorptiometry. Bone morphometric parameters and microarchitectural properties were determined by micro-computed tomography and histomorphometry of the distal metaphysis of femurs. Alterations of bone metabolism-related factors were evaluated by cytokine array. Effects of GGT on osteoblasts or stromal cells were evaluated by RT-PCR, enzyme activity, and mineralization ability.Results
Serum levels of GGT were significantly elevated in the BDL-group. In the BDL group, BMD, bone mass percentage, and osteoblast number were significantly decreased, whereas osteoclast number was significantly increased. These alterations were markedly attenuated in the AGT group. The mRNA levels of vascular endothelial growth factor-A, LPS-induced CXC chemokine, monocyte chemoattractant protein-1, tumor necrosis factor-α interleukin-1β and receptor activator of nuclear factor-kappa B ligand were upregulated, and those of interferon-γ and osteoprotegerin were downregulated in the GGT-treated stromal cells. Furthermore, GGT inhibited mineral nodule formation and expression of alkaline phosphatase and bone sialo-protein in osteoblastic cells.Conclusion
Our results indicate that elevated GGT level is involved in hepatic osteodystrophy through secretion of bone resorbing factor from GGT-stimulated osteoblasts/bone marrow stromal cells. In addition, GGT also possesses suppressive effects on bone formation. Managing elevated GGT levels by anti-GGT antibody may become a novel therapeutic agent for hepatic osteodystrophy in chronic liver diseases. 相似文献67.
68.
Yoshida Takanori Nagai Hisako Yahara Tetsukazu Tachida Hidenori 《Journal of plant research》2010,123(4):607-616
Zanthoxylum ailanthoides Siebold & Zucc. is one of the most frequently encountered pioneer trees in Japanese warm–temperate evergreen oak forests.
Our previous study in one region of Japan suggested high levels of population differentiation and putative natural selection
acting on one of the nuclear loci analyzed. Here, we extend our analysis to study the genetic structure of 10 populations
of Z. ailanthoides across Japan using 9 simple sequence repeat (SSR) loci for a better understanding of its genetic structure. First, the southernmost
population (Kagoshima) in the samples was found to have the highest genetic diversity, suggesting there was a glacial refugium
at or near the location of the population. Second, relatively strong genetic differentiation was found among populations,
and there was a positive correlation between genetic distances and geographic distances (Mantel test; P < 0.001). Based on this information, we analyzed nucleotide variation at the putatively selected locus homologous to the
gene encoding the ADP-glucose pyrophosphorylase large subunit (agpL). Despite the strong genetic differentiation among populations suggested by the SSR loci, the agpL locus was monomorphic in almost all populations analyzed. The results of this study strongly supported the possibility of
a selective sweep at or near the agpL locus. 相似文献
69.
Maekawa M Iwayama Y Watanabe A Nozaki Y Ohnishi T Ohba H Toyoshima M Hamazaki K Osumi N Aruga J Yoshikawa T 《Biochemical and biophysical research communications》2010,402(2):431-437
The eyes are riched in long-chain polyunsaturated fatty acids (LC-PUFAs) such as arachidonic acid [ARA; 20:4 (n−6)] and docosahexaenoic acid [DHA; 22:6 (n−3)]. Despite their abundance in the eyes, ARA and DHA cannot be sufficiently synthesized de novo in mammals. During gestation, eye development is exceptionally rapid, and substantial amounts of LC-PUFAs are needed to ensure proper eye development. Here, we studied the influences of dietary LC-PUFAs in dams (C57BL/6 and C3H/He) on the eye morphogenesis and organogenesis of their pups. Intriguingly, fetuses and newborn mice from C57BL/6 dams fed an LC-PUFA (particularly ARA)-enriched diet displayed a much higher incidence of eye abnormalities such as microphthalmia (small eye) and corneal opacity than those from dams fed an LC-PUFA-poor diet. The effects of LC-PUFAs on eye anomalies were evident only in the female pups of C57BL/6 inbred mice, not in those of C3H/He mice or male C57BL/6 mice. These results demonstrate a gene-by-environment (GxE) interaction in eye development in mice. Furthermore, our molecular analysis suggested the potential roles of Pitx3 and Pax6 in the above interaction involving ARA. 相似文献
70.
Altered interaction of the matrix protein with the cytoplasmic tail of hemagglutinin modulates measles virus growth by affecting virus assembly and cell-cell fusion
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Clinical isolates of measles virus (MV) use signaling lymphocyte activation molecule (SLAM) as a cellular receptor, whereas vaccine and laboratory strains may utilize the ubiquitously expressed CD46 as an additional receptor. MVs also infect, albeit inefficiently, SLAM(-) cells, via a SLAM- and CD46-independent pathway. Our previous study with recombinant chimeric viruses revealed that not only the receptor-binding hemagglutinin (H) but also the matrix (M) protein of the Edmonston vaccine strain can confer on an MV clinical isolate the ability to grow well in SLAM(-) Vero cells. Two substitutions (P64S and E89K) in the M protein which are present in many vaccine strains were found to be responsible for the efficient growth of recombinant virus in Vero cells. Here we show that the P64S and E89K substitutions allow a strong interaction of the M protein with the cytoplasmic tail of the H protein, thereby enhancing the assembly of infectious particles in Vero cells. These substitutions, however, are not necessarily advantageous for MVs, as they inhibit SLAM-dependent cell-cell fusion, thus reducing virus growth in SLAM(+) B-lymphoblastoid B95a cells. When the cytoplasmic tail of the H protein is deleted, a virus with an M protein possessing the P64S and E89K substitutions no longer grows well in Vero cells yet causes cell-cell fusion and replicates efficiently in B95a cells. These results reveal a novel mechanism of adaptation and attenuation of MV in which the altered interaction of the M protein with the cytoplasmic tail of the H protein modulates MV growth in different cell types. 相似文献