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1.
Summary The distribution of the mRNAs for chromogranin A and B was analyzed by in situ hybridization with 35S-labeled oligonucleotide probes in formalin-fixed paraffin-embedded carcinoid tumor tissues. All the 15 mid-gut carcinoid tumors examined contained both mRNAs for chromogranin A and B at high level in tumor cells. Sixteen of 18 bronchial carcinoid tumors but only 2 of 5 rectal carcinoid tumors expressed one or both species of chromogranin mRNAs. The same tendency was seen with the argyrophil reaction according to Grimelius where most of the mid-gut tumor cells were uniformly stained, while considerable variation in reactivity was seen in some of the bronchial and rectal carcinoid tumor cells. The sequential sections were stained with a monoclonal antibody against chromogranin A and a polyclonal antiserum which reacts with both chromogranins. The expression of the mRNA for chromogranin A on the carcinoid tumors was almost concordant with that of chromogranin B as well as with the chromogranin A protein, whereas almost all tumors stained positively with the polyclonal antibodies. Analyses of mRNA expression of chromogranin A before and after interferon therapy on 4 patients with mid-gut carcinoids indicated an inhibition at pre-translational level. In conclusion, the mRNAs for chromogranin A and B are good markers for the carcinoid tumors, especially of mid-gut origin. Fore-gut, mid-gut and rectal carcinoid tumors are different in their endocrine properties regarding the expression of the chromogranins.  相似文献   
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Data are presented suggesting that birds have evolved eggs with shells containing different structures (numbers of mammillae per unit of inner eggshell surface area, i.e., mammillary densities) to cope up with different calcium requirements imposed by different growth rates and modes of development. Precocial bird species grow slowly, but have high mammillary density, while altricial bird species grow rapidly, but have low mammillary density. These results suggest an adaptation associated with growth rate and mode of development and show, moreover, that the mammillary layer is indicative of the breeding biology of the bird. J. Morphol. 2012. © 2011 Wiley Periodicals, Inc.  相似文献   
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The title compound, 2-{4-[3-(2,5-dimethylphenyl)-3-methylcyclobutyl]thiazol-2-yl}isoindoline-1,3-dione (C24H22N2O2S), was synthesized and characterized by IR-NMR spectroscopy and single-crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P21/c with a?=?19.7799(13) Å, b?=?6.7473(4) Å, c?=?15.7259(9) Å and β?=?103.416(5)°. In addition, the molecular geometry, vibrational frequencies and gauge including atomic orbital (GIAO) 1H and 13C chemical shift values of the title compound in the ground state have been calculated by using the Hartree-Fock (HF) and density functional method (DFT/B3LYP) with 6–31G(d), 6–31 + G(d,p) and LANL2DZ basis sets, and compared with the experimental data. To determine conformational flexibility, molecular energy profile of the title compound was obtained by semi-empirical (AM1) calculations with respect to two selected degrees of torsional freedom, which were varied from ?180° to +180° in steps of 5°. Besides, molecular electrostatic potential, frontier molecular orbitals (FMO) analysis and thermodynamic properties of the title compound were investigated by theoretical calculations.  相似文献   
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The suborder Myrmeleontiformia is a derived lineage of lacewings (Insecta: Neuroptera) including the families Psychopsidae, Nemopteridae, Nymphidae, Ascalaphidae and Myrmeleontidae. In particular, Myrmeleontidae (antlions) are the most diverse neuropteran family, representing a conspicuous component of the insect fauna of xeric environments. We present the first detailed quantitative phylogenetic analysis of Myrmeleontiformia, based on 107 larval morphological and behavioural characters for 36 genera whose larvae are known (including at least one representative of all the subfamilies of the suborder). Four related families were used as outgroups to polarize character states. Phylogenetic analyses were conducted using both parsimony and Bayesian methods. The reconstructions resulting from our analyses corroborate the monophyly of Myrmeleontiformia. Within this clade, Psychopsidae are recovered as the sister family to all the remaining taxa. Nemopteridae (including both subfamilies Nemopterinae and Crocinae) are recovered as monophyletic and sister to the clade comprising Nymphidae + (Myrmeleontidae + Ascalaphidae). Nymphidae consist of two well‐supported clades corresponding to the subfamilies Nymphinae and Myiodactylinae. Our results suggest that Ascalaphidae may not be monophyletic, as they collapse into an unresolved polytomy under the Bayesian analysis. In addition, the recovered phylogenetic relationships diverge from the traditional classification scheme for ascalaphids. Myrmeleontidae are reconstructed as monophyletic, with the subfamilies Stilbopteryginae, Palparinae and Myrmeleontinae. We retrieved a strongly supported clade comprising taxa with a fossorial habit of the preimaginal instars, which represents a major antlion radiation, also including the monophyletic pit‐trap building species.  相似文献   
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Summary A local isolate of Bacillus thuringiensis (B.t.81) produced crystal protein which was identified as a cry I gene of Class I. The synthesis and assembly of crystal complements were investigated at intervals throughout the growth cycle. Incubation temperature had a marked effect on toxin synthesis; production being the highest at 25°C and the lowest at 42°C. The mutants of B. t. 81, unable to synthesize crystal protein complements, have also been described.  相似文献   
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1. Termites are one of the most important invertebrate ecosystem engineers in tropical regions, which may be quantified using termite biomass data. However, biomass data are particularly difficult to collect as they rely on termites being weighed in the field, which may neither be possible nor convenient. Local scale linear regression models, based on termite head widths (mm) and body masses (mg), have been used in the past to estimate termite biomass using head width and abundance data. However, these models represent very limited numbers of termite taxa from single sites. In the present study, I provide one of the most representative linear regression models available based on 90 samples from three different countries (Peru, Kenya, and Malaysia). 2. Although the linear regression model under‐ or overestimated body weights of taxa with characteristic features (e.g. large heads of Odontotermes workers or elongated abdomens of Kalotermitidae) it provides a robust method for estimating termite biomass at the community level. Additionally, while there are limitations related to the general model, which may be solved by focusing on taxa specific data and the use of higher accuracy equipment, it is the first model to facilitate termite biomass estimates using the head with and abundance data only. 3. This study encourages the use of termite biomass data to gain a better understanding of termites in ecosystem processes and calls for comparative data to be gathered for the purpose of creating models that may be representative of the variability among termite taxa.  相似文献   
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Quarter samples of foremilk and residual milk were taken approximately every second week from 2 days post partum (pp) throughout lactation month 9, from 5 dairy cows in their second lactation period. Bacteriologically positive milk samples were excluded. The aim was to study the variation in total and differential leukocyte counts, N-acetyl-ß-D-glucosaminidase (NAGase), antitrypsin (ATR) and serum albumin (BSA) in milk during the lactation period and different stages of oestrous cycle. Also the between milkings variation was studied from lactation month 4 to 9. At 2 days pp, each fraction of milk contained significantly higher numbers of leukocytes and had a higher activity of NAGase and ATR than later in the lactation period. In foremilk the highest content of BSA was also recorded at 2 days pp. From lactation month 2 to 9, stage of lactation had, in general, a slight effect on the variation in the variables measured. The total leukocyte count in residual milk tended to increase as lactation proceeded. The proportion of monocyte-macrophages in foremilk was significantly decreased during the last 4 months. NAGase and BSA in both fractions and ATR in residual milk increased significantly towards the end of the lactation period. From lactation month 4 to 9 the highest recorded ranges of variation between milkings, within quarter and stage of lactation, in the total leukocyte count, proportions of neutrophils, lymphocytes, monocyte-macrophages, NAGase, ATR and BSA in foremilk were 215 × 103ml, 42 %, 34 %, 54 %, 6.68 units, 0.36 units and 0.14 mg/ml respectively. The corresponding figures in residual milk were higher except for the variation in BSA which was slightly lower in residual milk than in foremilk. In residual milk there was a positive correlation between the proportion of neutrophils and the total leukocyte count, when calculated on data from all cows and the entire experimental period. During the oestrous periods, the proportion of neutrophils in residual milk was higher than during the dioestrous periods. Foremilk and residual milk differed in the total as well as the differential leukocyte counts in all the various stages of lactation, whereas the contents of NAGase, ATR and BSA were equal in both fractions. The exception was 2 days pp when the proportions of lymphocytes were equal in both fractions and BSA-significantly higher in foremilk than in residual milk.  相似文献   
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