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81.
82.
This paper compares the species richnesses, Bray–Curtis similarities, species diversities, evennesses, and the results of
various analyses (multivariate, logarithmic series, and lognormal distribution analyses) of insects from four orders (viz.,
Hemiptera, Orthoptera, aculeate Hymenoptera, and Coleoptera) inhabiting a medicinal plant, Calotropis procera among eight sites within industrial and nonindustrial zones in the Purba Medinipur district (erstwhile Midnapore), West Bengal,
India. Both cluster analysis and principal component analysis indicate an effect of industrialization on the diversity of
the four insect orders. The species community at each site exhibits an almost pure lognormal distribution. Bootstrap estimation
of species diversity also points to the effect of industrialization. A comparison of the values of x and N/S of the logarithmic series indicates a typical relationship between the species community and its diversity. The number of
unique species among the eight study sites is 6 according to jackknife estimation. Beta-diversity analysis of the samples
shows the impact of industrialization on the abundances and species richness of the insects. Altogether, 16 types of analytical
procedure are applied for this purpose, and their suitabilities for this kind of data set are assessed. Disturbance, probably
due to industrial emissions, has changed the compositions and structures of the insect communities out to a distance of at
least 6 km from the core industrial area. 相似文献
83.
Prakash C. Misra Theodore A. Craig Frederick L. Crane 《Journal of bioenergetics and biomembranes》1984,16(2):143-152
Carrot (Daucus carota L.) cells grown in suspension culture oxidized exogeneous NADH. The NADH oxidation was able to stimulate K+ (86Rb+) transport into cells, but it did not affect sucrose transport.N,N'-Dicyclohexyl-carbodiimide, diethylstilbestrol, and oligomycin, which only partially inhibited NADH oxidation, almost completely collapsed the K+ (86Rb+) transport. Vanadate, which is less effective as an ion transport inhibitor, was less effective in inhibiting the NADH-driven transport of K+ (86Rb+).p-Fluormethoxycarbonylcyanide phenylhydrazone inhibits the K+ transport over 90% including that induced by NADH. The results are interpreted as evidence that a plasma membrane redox system in root cells is closely associated with the ATPase which can drive K+ transport. Because of the inhibitor effects, it appears that membrane components common to the redox system and ATPase function in the transport of K+. 相似文献
84.
Isolation and characterization of OmpC porin mutants with altered pore properties. 总被引:10,自引:6,他引:10 下载免费PDF全文
The LamB protein is normally required for the uptake of maltodextrins. Starting with a LamB- OmpF- strain, we have isolated mutants that will grow on maltodextrins. The mutation conferring the Dex+ phenotype in the majority of these mutants has been mapped to the ompC locus. These mutants, unlike LamB- OmpF- strains, grew on maltotriose and maltotetraose, but not on maltopentaose, and showed a significantly higher rate of [14C]maltose uptake than the parent strain did. In addition, these mutants showed increased sensitivity to certain beta-lactam antibiotics and sodium dodecyl sulfate, but did not exhibit an increase in sensitivity to other antibiotics and detergents. The nucleotide sequence of these mutants has been determined. In all cases, residue 74 (arginine) of the mature OmpC protein was affected. The results suggest that this region of the OmpC protein is involved in the pore domain and that the alterations lead to an increased pore size. 相似文献
85.
Biswapriya B. Misra Ram P. Upadhayay Laura A. Cox Michael Olivier 《Metabolomics : Official journal of the Metabolomic Society》2018,14(6):75
Introduction
Metabolomics is a promising approach for discovery of relevant biomarkers in cells, tissues, organs, and biofluids for disease identification and prediction. The field has mostly relied on blood-based biofluids (serum, plasma, urine) as non-invasive sources of samples as surrogates of tissue or organ-specific conditions. However, the tissue specificity of metabolites pose challenges in translating blood metabolic profiles to organ-specific pathophysiological changes, and require further downstream analysis of the metabolites.Objectives
As part of this project, we aim to develop and optimize an efficient extraction protocol for the analysis of kidney tissue metabolites representative of key primate metabolic pathways.Methods
Kidney cortex and medulla tissues of a baboon were homogenized and extracted using eight different extraction protocols including methanol/water, dichloromethane/methanol, pure methanol, pure water, water/methanol/chloroform, methanol/chloroform, methanol/acetonitrile/water, and acetonitrile/isopropanol/water. The extracts were analyzed by a two-dimensional gas chromatography time-of-flight mass-spectrometer (2D GC–ToF-MS) platform after methoximation and silylation.Results
Our analysis quantified 110 shared metabolites in kidney cortex and medulla tissues from hundreds of metabolites found among the eight different solvent extractions spanning low to high polarities. The results revealed that medulla is metabolically richer compared to the cortex. Dichloromethane and methanol mixture (3:1) yielded highest number of metabolites across both the tissue types. Depending on the metabolites of interest, tissue type, and the biological question, different solvents can be used to extract specific groups of metabolites.Conclusion
This investigation provides insights into selection of extraction solvents for detection of classes of metabolites in renal cortex and medulla, which is fundamentally important for identification of prognostic and diagnostic metabolic kidney biomarkers for future therapeutic applications.86.
Y Takei F C Kauffman U K Misra H Yamanaka R G Thurman 《Biochimica et biophysica acta》1990,1036(3):242-244
Periportal and pericentral regions of the liver lobule were isolated from perfused rat liver using a micropunch and incubated in Krebs-Henseleit buffer (pH 7.6) containing 2% poly(ethylene glycol) in Eagle's basal medium, PMSF (50 micrograms/ml) and leupeptin (20 micrograms/ml) for 2 h at 25 degrees C under and O2/CO2 (95:5%) gas phase. Maximal rates of urea production from ammonium chloride were 96.4 +/- 8.7 and 32.8 +/- 5.4 mumol/g per h at 800 and 200 microM O2. Thus, urea synthesis was 2-3-times greater at high than low O2 tension in plugs from periportal and pericentral regions of the liver lobule. 相似文献
87.
HeLa cells are human cervical cancer cells with HR HPV-18 genes integrated in the genome. The functions of tumor suppressor proteins p53 and pRB are abrogated and cell cycle regulation becomes nonfunctional. The aim of the present study was to investigate whether the CDK inhibitor R-Roscovitine would allow the G1/S blocked HeLa cells to enter into mitosis prematurely and induce apoptosis. HeLa cells blocked in G1/S border were treated with different concentrations of Roscovitine for 4 and 18 h respectively. Induction of apoptosis was studied by FACS and DNA fragmentation. Presence of γH2AX in the treated cells was studied by confocal microscopy. Expression levels of CASP3, CDKN1A i.e. p21 (Cip1/Waf1) and Bcl2 were studied by semi-quantitative RT-PCR to analyze the role played by these proteins in Roscovitine induced apoptosis in G1/S blocked HeLa cells. Results indicate that the Roscovitine allowed the thymidine blocked HeLa cells to enter into mitosis prematurely. Presence of γH2AX loci in treated cells indicates DNA damage in prematurely mitotic cells. Analysis of DNA fragmentation and chromatin condensation confirmed apoptosis as the possible mechanism of Roscovitine induced cell death. Our results also reveal that Roscovitine induced apoptosis is associated with the overexpression of CASP3, p21 (cip1/waf1) and Bcl2. 相似文献
88.
G Bhattacharjee U K Misra G Gawdi G Cianciolo S V Pizzo 《Journal of cellular biochemistry》2001,82(2):260-270
Thioglycollate (TG)-elicited murine, peritoneal macrophages express two receptors for activated forms of the proteinase inhibitor alpha2-macroglobulin (alpha2M*)--namely, the low density lipoprotein receptor-related protein (LRP) and the alpha2M signaling receptor (alpha2MSR). We now report that resident peritoneal macrophages express only 400+/-50 alpha2MSR receptors/cell compared to 5000+/-500 receptor/TG-elicited macrophage. By contrast, LRP expression is only 2-2.5-fold greater on elicited cells. The low level of alpha2MSR expression by resident cells is insufficient to trigger signal transduction in contrast to TG-elicited cells which when exposed to alpha2M* demonstrate a rapid rise in inositol 1,4,5-trisphosphate and a concomitant increase in cytosolic free Ca2+. We then studied a variety of preparations injected subcutaneously for their ability to upregulate alpha2MSR. Macroaggregated bovine serum albumin (macroBSA) injection upregulated alpha2MSR and triggered signaling responses by splenic macrophages. Nonaggregated BSA injection alone or in the presence of alum, by contrast, did not alter alpha2MSR expression. Recombivax (hepatitis B antigen adsorbed to alum) injection also upregulated alpha2MSR on splenic macrophages while the alum carrier had no effect. We conclude that macrophage alpha2M* receptors are inducible and their expression may be regulated, in part, by potential antigens. 相似文献
89.
Effect of Feeding Bengal Gram (Cicer arietinum) at Different Protein Levels on Plasma Lipids of Rats
L-Amino acid ligase catalyzes the formation of an α-peptide bond from unprotected L-amino acids in an ATP-dependent manner, and this enzyme is very useful in efficient peptide production. We performed enzyme purification to obtain a novel L-amino acid ligase from Bacillus subtilis NBRC3134, a microorganism producing peptide-antibiotic rhizocticin. Rhizocticins are dipeptide or tripeptide antibiotics and commonly possess L-arginyl-L-2-amino-5-phosphono-3-cis-pentenoic acid. The purification was carried out by detecting L-arginine hydroxamate synthesis activity, and a target enzyme was finally purified 1,280-fold with 0.8% yield. The corresponding gene was then cloned and designated rizA. rizA was 1,242 bp and coded for 413 amino acid residues. Recombinant RizA was prepared, and it was found that the recombinant RizA synthesized dipeptides whose N-terminus was L-arginine in an ATP-dependent manner. RizA had strict substrate specificity toward L-arginine as the N-terminal substrate; on the other hand, the substrate specificity at the C-terminus was relaxed. 相似文献
90.