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51.
TRAIL-transduced dendritic cells protect mice from acute graft-versus-host disease and leukemia relapse 总被引:7,自引:0,他引:7
Sato K Nakaoka T Yamashita N Yagita H Kawasaki H Morimoto C Baba M Matsuyama T 《Journal of immunology (Baltimore, Md. : 1950)》2005,174(7):4025-4033
TRAIL preferentially induces apoptotic cell death in a wide variety of transformed cells, whereas it induces no apoptosis, but inhibits activation of Ag-specific T cells via blockade of cell cycle progression. Although accumulating results suggest that TRAIL is involved in the maintenance of immunological homeostasis under steady state conditions as well as in the initiation and progression of immunopathologies, the potential regulatory effect of TRAIL on immune responses and its therapeutic potential in immunological diseases remains unclear. We report in this study the potential usefulness of TRAIL-transduced dendritic cells (DCs) for the treatment of lethal acute graft-vs-host disease (GVHD) and leukemia relapse. DCs genetically modified to express TRAIL showed potent cytotoxicity against both alloreactive T cells and leukemic cells through the induction of apoptosis. In addition, treatment with genetically modified DCs expressing TRAIL of allogeneic BM transplants recipients with leukemia was effective for protection against acute GVHD and leukemia relapse. Thus, gene transfer of TRAIL to DCs is a novel modality for the treatment of acute GVHD and leukemia relapse by selective targeting of pathogenic T cells and leukemic cells. 相似文献
52.
Irino Y Cho H Nakamura Y Nakahara M Furutani M Suh PG Takenawa T Fukami K 《Biochemical and biophysical research communications》2004,320(2):537-543
To date, 12 phospholipase C (PLC) isozymes have been identified in mammals, and they are divided into five classes, beta-, gamma-, delta-, epsilon-, and zeta-type. PLCdelta-type is reported to be composed of four isozymes, PLCdelta1-delta4. Here we report that a screening for mouse PLCdelta2 from a BAC library with primers that amplify a specific region of bovine PLCdelta2 resulted in isolation of one clone containing the mouse PLCdelta4 gene. Furthermore, a database search revealed that there is only one gene corresponding to PLCdelta2 and PLCdelta4 in the mouse and human genomes, indicating that bovine PLCdelta2 is a homologue of human and mouse PLCdelta4. However, PLCdelta2 Western blot analysis with a widely used commercial anti-PLCdelta2 antibody showed an expression pattern distinct from that of PLCdelta4 in wild-type mice. In addition, an 80-kDa band, which was recognized by antibody against PLCdelta2, was smaller than an 85-kDa band detected by anti-PLCdelta4 antibody, and the 80-kDa band was detectable in lysates of brain, testis, and spleen from PLCdelta4-deficient mice. We also found that immunoprecipitates from brain lysates with this PLCdelta2 antibody contained no PLC activity. From these data, we conclude that bovine PLCdelta2 is a homologue of human and mouse PLCdelta4, and that three isozymes (delta1, delta3, and delta4) exist in the PLCdelta family. 相似文献
53.
Cryptosporidium spp. has been found in more than 150 species of mammals, but there has been no report in mongooses. In this study, we report the isolation of Cryptosporidium sp. in a banded mongoose Mungos mungo, which was brought from Tanzania to Japan; the isolate was analyzed genetically to validate the occurrence of a new, host-adapted genotype. Cryptosporidium diagnostic fragments of 18S ribosomal RNA and 70-kDa heat shock protein genes were amplified from this isolate and compared with the other Cryptosporidium species and genotypes reported previously. Analyses showed that the mongoose isolate represents a new genotype, closely related to that of bears. 相似文献
54.
Production of recombinant human erythropoietin/Fc fusion protein by genetically manipulated chickens
Carlos Alberto Penno Yoshinori Kawabe Akira Ito Masamichi Kamihira 《Transgenic research》2010,19(2):187-195
We previously reported the production of human erythropoietin (hEpo) using genetically manipulated (GM) chickens. The recombinant
hEpo was produced in the serum and egg white of the GM chickens, and the oligosaccharide chain structures of the serum-derived
hEpo were more favorable than those of the egg white-derived hEpo. In the present study, a retroviral vector encoding an expression
cassette for a fusion protein of hEpo and the Fc region of human immunoglobulin G (hEpo/Fc) was injected into developing chicken
embryos, with the aim of recovering the serum-derived hEpo from egg yolk through the yolk accumulation mechanism of maternal
antibodies. The GM chickens that hatched stably produced the hEpo/Fc fusion protein not only in their serum and egg white,
but also in the egg yolk as expected. Lectin blot analyses revealed that significant amounts of the oligosaccharide chains
of hEpo/Fc produced in the serum and eggs of GM chickens terminated with galactose, and that the oligosaccharide chains of
the serum- and yolk-derived hEpo/Fc incorporated sialic acid residues. Moreover, biological activity assessment using Epo-dependent
cells revealed that the yolk-derived hEpo/Fc exhibited a comparable performance to the serum- and CHO-derived hEpo/Fc. These
results indicate that transport of Fc fusion proteins from the blood circulation to the yolk in chickens represents an effective
strategy for the production of pharmaceutical glycoproteins using transgenic chicken bioreactors. 相似文献
55.
To study the effects of intraventricular flow dynamics on the aortic flow, we created an integrated model of the left ventricle and aorta and conducted a computer simulation of diastolic and systolic blood flow within this model. The results demonstrated that the velocity profile at the aortic annulus changed dynamically, and was influenced by the intraventricular flow dynamics. The profile was almost flat in early systole but became nonuniform as systole progressed, and was skewed toward the posterior side in midsystole and toward the anterior side in later systole. At a distance from the aortic annulus, a different velocity profile was induced by the twisting and torsion of the aorta. In the ascending aorta, the fastest flow was initially located in the posteromedial sector, and it moved to the posterior section along the circumference as systole progressed. The nonuniformity of the aortic inflow gave rise to a complex wall shear stress (WSS) distribution in the aorta. A comparison of the WSS distribution obtained in this integrated analysis with that obtained in flow calculations using an isolated aorta model with Poiseuille and flat inlet conditions showed that intraventricular flow affected the WSS distribution in the ascending aorta. These results address the importance of an integrated analysis of flow in the left ventricle and aorta. 相似文献
56.
Sano S Okawa A Nakajima A Tahara M Fujita K Wada Y Yamazaki M Moriya H Sasho T 《Cell and tissue research》2006,323(2):245-252
To investigate the mechano-transduction system of cells, we identified genes responsive to a cyclic mechanical stimulus. MC3T3.E1
cells were cultured on a computer-controlled vacuum-pump-operated device designed to provide a cyclic mechanical stimulus.
A maximum elongation of 15% of membrane at 10 cycles/min (3 s extension followed by 3 s relax per cycle) was repeated for
48 h. By means of a differential display, the gene expression pattern of cells exposed to the stimulus was compared with that
of unexposed cells. As a result, a gene fragment that was exclusively expressed in mechanically stressed cells was identified.
By using expressed sequence tag walking together with the oligo-capping method, this gene was identified as phosphatidylinositol
4-phosphate 5-kinase type II β (initially known as Pip5k2β but now reclassified as Pip4k2β). The specific up-regulation of Pip4k2β upon mechanical stimulus was also confirmed by using another apparatus, viz. a computer-controlled linearized-stepping motor
system. To examine the involvement of the cyclic mechanical stimulus in the regulation of Pip4k2β expression in musculoskeletal tissue, we created an Achilles tendon transection model in rabbits. The temporal expression
of Pip4k2β was assessed by means of a quantitative reverse-transcribed polymerase chain reaction. In the gastrocnemius muscle, expression
of Pip4k2β rapidly decreased 1 week after transection but was restored to normal levels at 4 weeks. In the Achilles tendon, however,
expression remained decreased until 4 weeks after transection. We suggest that the expression of Pip4k2β can be used as a marker for cells receiving a suitable mechanical stimulus.
This study was supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Science, Sports and Culture
of Japan. 相似文献
57.
A novel strain of Halomonas (Tc-202), which has the capability of removing Tc(VII) from solid- and aqueous-phase material aerobically, was isolated from the marine environment. Tc-202 removed 55% of the total 99Tc in solutions at 15 degrees C by reducing Tc(VII) to Tc(V), but other Halomonas strains did not. 相似文献
58.
Generation of DNA-free Escherichia coli cells by 2-aminopurine requires mismatch repair and nonmethylated DNA 下载免费PDF全文
Undirected mismatch repair initiated by the incorporation of the base analog 2-aminopurine kills DNA-methylation-deficient Escherichia coli dam cells by DNA double-strand breakage. Subsequently, the chromosomal DNA is totally degraded, resulting in DNA-free cells. 相似文献
59.
Cytochemical localization of adenylate cyclase activity in the theca folliculi of the mouse graafian follicle 总被引:1,自引:0,他引:1
Summary The adenylate cyclase activity in the theca folliculi of the mouse Graafian follicle was investigated using the electron microscopic cytochemistry. Deposits of reaction product are recognized on the plasma membrane of the fibroblast, theca cell and transitional cell from the fibroblast-like cell to the theca cell (partially or incompletely differentiated theca cell) after incubation with adenylyl-imidodiphosphate (AMP-PNP) as an effective substrate for adenylate cyclase. This fact indicates that these cells have the receptor on the plasma membrane, and the adenylate cyclase-cyclic AMP system is important for the steroid secretion or the collagen fiber production. It is difficult to clarify by this method the relationship between the adenylate cyclase activity and the functional differentiation of the theca cell.Supported by a grant from the Japanese Educational ministry 相似文献
60.
Schönenberger J von Balthazar M Takahashi M Xiao X Crane PR Herendeen PS 《Annals of botany》2012,109(5):921-936