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Monoclonal anti-mouse macrophage antibodies recognize the globular portions of C1q, a subcomponent of the first component of complement 总被引:1,自引:0,他引:1
H P Heinz H Dlugonska E Rüde M Loos 《Journal of immunology (Baltimore, Md. : 1950)》1984,133(1):400-404
One of seven monoclonal antibodies generated against mouse macrophages (M phi) was found to recognize isolated heterologous C1q. This antibody was shown to be cytotoxic and to react in a strain-independent way with mouse M phi derived from bone marrow cells as well as with M phi from the peritoneal cavity; it did not react, however, with mouse granulocytes, thymocytes, or T and B lymphocytes. The hemolytic activity of fluid phase C1q was inhibited to 50% at a 2 X 10(-4) dilution of hybridoma supernatant, whereas a 100-fold higher concentration was required to inhibit C1q bound to immune complexes ( EAC1q ) to the same extent. It was demonstrated that this antibody recognizes the isolated globular, Fc-binding portions of the C1q molecule and reacts with the A and B chains. Because M phi have been shown to synthesize C1q, the Fc-recognizing subcomponent of the first component of complement, evidence was provided that endogeneous C1q can serve as an Fc receptor on M phi during secretion. This fact was demonstrated by a dose-dependent inhibition of Fc-receptor activity for EIgG by the F(ab')2 fragment of this monoclonal antibody. These experiments further support the concept that C1q produced by M phi functions on the surface as an Fc-recognizing molecule before it is released and incorporated into the macromolecular complex of serum C1. 相似文献
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BACKGROUND: Clinical outcome predictions in phase III studies are mostly derived for patient groups, but not for individual patients, although individualised predictions are an ultimate goal to permit a personalised fine tuning of therapy. This may permit earlier application of target therapies, minimise general damage to the organism, and result in improved complete remission rates in malignant diseases. METHODS: In this study, Lymphochip cDNA microarray gene expression results of DLBCL patients, from a published prospective meta-analysis study on the prediction of group prognosis, were analysed for individualised predictions using a nonstatistical data pattern classification approach. The training set was comprised of the same 160 DLBCL patients as in the prognosis study, with the validation set of 80 patients remaining unknown to the learning process. This permits the assessment of prospective classifier performance towards unknown patients. RESULTS: Pretherapeutic predictions for the training and validation set patients were correct in 98.1% and 78.3% of the cases for nonsurvival and in 67.3% and 45.3% for survival. The discriminatory data pattern consisted of 14 known and 10 unknown gene products. CONCLUSIONS: The better than 95% correct pretherapeutic prediction for about one-half of the ultimately nonsurviving high-risk patients of the training set is promising for clinical considerations about individualised therapy in such cases. Reliable individualised survival predictions are not possible with the information content of the present dataset. It seems necessary to investigate additional gene products, since survival may significantly depend on non-lymphocyte-associated genes that escape to the lymphocyte-oriented Lymphochip gene activation analysis. 相似文献
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H.-Dietmar Behnke 《Nordic Journal of Botany》1991,11(3):333-344
The phloem of the Myristicaceae is composed of sieve elements, parenchymatous cells, and fibers. Within the metaphloem and secondary phloem parenchymatic layers including prominent secretory elements alternate with tangential bands of fibers and layers composed of sieve elements, companion cells and phloem-parenchyma cells. among the latter the sieve elements are most abundant and easily identified by the presence of thick (nacreous) walls. The most characteristic feature of the sieve elements of Myristicaceae (and found nowhere else among the Magnoliiflorae) are nuclear crystals, which are released into the lumen during nuclear degeneration and persist in the mature cell. P-and S-type sieve-element plastids were recorded for the 18 species investigated. Both types of the plastid are characterized by large diameters and many medium-sized starch grains. The sizes and contents (small protein crystals only) of the P-type plastids of the Myristicaceae do not conform to the tiny P-type plastids (with large protein crystals) of the Annonaceae, a family to which the Myristicaceae is traditionally allied. 相似文献
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The rat major histocompatibility complex class I antigens RT1.Au and RT1.Eu from the u haplotype and RT1.An from the n haplotype were labeled with 14C-asparagine or with 3H-fucose, mannose, galactose, and N-acetylglucosamine. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis showed complete removal of radioactivity from the sugar-labeled antigen heavy chains by digestion with glycopeptidase F, an enzyme that removes N-linked glycans completely. High performance liquid chromatography analysis of the tryptic digests of the mixed sugar-labeled and asparagine-labeled antigens demonstrated that all the sugar-labeled peptides were coincident with asparagine-labeled peptides. The An antigen showed three glycopeptides, each of which had different amounts of sugar radioactivity. The antigens Au and Eu showed two glycopeptides with different amounts of radioactivity but at identical positions in the two antigens. Antigen Eu had an additional glycopeptide with a lower amount of radioactivity. The positions of the glycopeptides from the Au and Eu antigens were different from those of the An antigen. The peptide profiles of the 14C-asparagine-labeled Au and Eu antigens demonstrated distinct differences between the molecules. The results of this study show that: (a) all the glycans on rat class I antigens are N-linked, as they are on H-2 and HLA class I antigens; (b) there are compositional differences among the glycans in each of the three antigens; (c) the glycosylation pattern of the rat class I antigens is similar to that of the mouse class I antigens, which contain two or three glycans, in contrast to that of the human class I antigens, which contain only one glycan; and (d) the antigens Au and Eu from the same haplotype are more closely related to each other than they are to the An antigen. 相似文献
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Kazuhiro Yamaguchi Klaus D. Jürgens Heinz Bartels Johannes Piiper 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1987,157(1):1-9
Summary To estimate the advantage of the small red blood cells (RBC) of high-altitude camelids for O2 transfer, the kinetics of O2 uptake into and release from the RBC obtained from llama, vicuña and alpaca were investigated at 37°C with a stopped-flow technique. O2 transfer conductance of RBC (G) was estimated from the rate of O2 saturation change and the corresponding O2 pressure difference between medium and hemoglobin. For comparison, O2 kinetics for the RBC of a lowaltitude camelid (dromedary camel) and the pygmy goat were determined and previously measured values for human RBC were used. O2 transfer of RBC was found to be strongly influenced by extracellular diffusion, except with O2 release into dithionite solutions of sufficiently high concentration (>30 mM). TheG values measured in these standard conditions,G
st (in mmol · min–1 · Torr–1 · (ml RBC)–1) were: high-altitude camelids, 0.58 (averaged for llama, alpaca and vicuña since there were no significant interspecific differences); camel 0.42; goat, 0.42; man, 0.39. The differences can in part be attributed to expected effects of the size and shape of the RBC (volume, surface area, mean thickness), as well as to the intracellular O2 diffusivity which depends on the concentration of cellular hemoglobin. The highG
st of RBC of highaltitude camelids may be considered to enhance O2 transfer in lungs and tissues. But the O2 transfer conductance of blood, , equal toG
st multiplied by hematocrit (in mmol · min–1 · Torr–1 · (ml blood)–1), was only slightly higher as compared to other species: 0.20 (llama, alpaca, vicuña), 0.14 (camel), 0.18 (goat), 0.17 (man).Abbreviations
DPG
2,3-diphosphoglycerate
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G
conductance
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Hb
hemoglobin
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RBC
red blood cells
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percent saturation of hemoglobin 相似文献
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The role of aromatic side chain residues in micelle binding by pancreatic colipase. Fluorescence studies of the porcine and equine proteins. 下载免费PDF全文
Fluorescence techniques have been employed to study the interaction of porcine and equine colipase with pure taurodeoxycholate and mixed micelles. Nitrotyrosine-55 of porcine colipase is obtained by modification with tetranitromethane (low excess, in the presence of taurodeoxycholate) of the protein followed by gel filtration and ion-exchange chromatography. Verification of the residue modified was obtained by h.p.l.c. peptide purification and sequence analysis. Reduction and quantitative reaction with dansyl chloride yields a fluorescent derivative that is twice as active in conjunction with lipase as is native colipase and that exhibits a strong emission band at 550 nm. Addition of micellar concentrations of taurodeoxycholate causes a 4.3-fold increase in the emission maximum as well as a 70 nm blue shift to 480 nm. Inclusion of oleic acid to form a mixed micelle reduces these spectral effects. Scatchard analysis of the data yield a Kd of 6.8 X 10(-4) M and a single colipase-binding site for taurodeoxycholate micelles. The data, by analogy to a phospholipase system, are consistent with a direct insertion of dansyl-NH-tyrosine-55 into the micelle. The presence of a single tryptophan residue (Trp-52) in equine colipase provides an intrinsic fluorescent probe for studying protein-micelle interaction. The emission maximum of horse colipase at 345 nm indicates a solvent-accessible tryptophan residue which becomes less so on binding of micelles. A blue shift of 8 nm and a 2-fold increase in amplitude is indicative of a more hydrophobic environment for tryptophan induced by taurodeoxycholate micelles. There is also a decrease in KSV for acrylamide quenching in the presence of micelles, which further supports a loss of solvent accessibility. The most dramatic pH effects are observed with KI quenching, and may indicate the presence of negative charges near Trp-52. 相似文献