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171.
C E Tan  J A Ballweg 《Social biology》1984,31(3-4):232-242
Desired family size and contraceptive behavior of 986 ever-married women aged 15-54 from Northern Mindanao, the Philippines, are described. Using the Dow and Werner typology of demographic and contraceptive patterns, it was found that a majority of the women were traditional in their demographic attitude and contraceptive behavior. A substantial proportion of the women desired medium to large families. In consistency in attitude and behavior was also manifested by women who desired small families but have never used efficient family planning methods. Sociodemographic characteristics of these women are described. A majority of the women who have never used efficient contraception also never practiced family planning. Rhythm was the primary method of birth control among demographic innovators and traditionals who have ever used inefficient methods; the pill was popular among contraceptive innovators and moderns. A considerable proportion of the demographic innovators and the traditionals were not currently using any family planning method; a lesser proportion of contraceptive innovators and moderns were also not using birth control methods. Relevance of the findings to family planning programs is pointed out. Recommendations are given. Motivation for a small family is a prerequisite for a successful family planning program. Without motivation, what family planning programs do is reduce the number of unwanted births. Family planning programs should reach out to those who are sufficiently motivated to have small families but have never used efficient family planning methods. A major finding of this research is that a majority of the women who never used efficient contraception also never used inefficient or traditional methods. Efforts should be made to change this. Additionally, efforts should be made to bring those modern and contraceptive innovators who had stopped using any family planning method to practice contraception again.  相似文献   
172.
Yeoh  H. H.  Tan  T. K.  Tian  K. E. 《Mycopathologia》1984,87(1-2):51-55
Species of Cunninghamella, Gliocladium deliquescens, Trichoderma harzianum and T. koningii were isolated from rotten wood chips. When grown on medium containing cellulose, all except Cunninghamella produced the three primary enzymes (exoglucanase, endoglucanase and -glucosidase) of the cellulase complex. The patterns for enzyme production, changes in mycelial mass and pH of the induction medium for T. harzianum and T. koningii were closely similar, and were distinguishable from those of G. deliquescens.  相似文献   
173.
Uptake of d-glucosamine by rat brain synaptosomes occurs via a saturable transport process (Km 2.1 mM, V 3.0 nmol/mg per min) which was clearly distinguishable from simple diffusion. This transport process is highly sensitive to cytochalasin (Ki = 7 · 10?5 mM. d-Glucose competitively inhibits d-glucosamine uptake with a Ki value of 8 · 10?1 mM.  相似文献   
174.
C.H. Tan  J. Robinson 《Life sciences》1982,30(14):1205-1210
The effect of 2-bromopalmitate, an inhibitor of fatty acid oxidation, on progesterone synthesis in isolated luteal cells was studied. Incubation of the cells with increasing concentrations (0 – 2 mM) of the inhibitor resulted in an initial enhancement of progesterone synthesis, both in the presence and absence of LH (1 μg/m1). In the LH-treated cells, this stimulation in steroid synthesis becomes markedly impaired at 2 mM 2-bromopalmitate. In the control cells, however, progesterone synthesis was sustained at the elevated level. At high concentrations of 2-bromopalmitate, the stimulatory effect of LH (relative to the controls) on steroidogenesis was progressively diminished, until it was completely abolished at an inhibitor concentration of 2 mM. The oxidation of labelled palmitic acid by luteal cells was also effectively inhibited by 2-bromopalmitate (1 mM). The results indicate that the steroidogenic effect of LH is mediated, in part, by fatty acid oxidation, and were explained in terms of the interaction between carbohydrate and fatty acid oxidation in supporting ovarian steroidogenesis.  相似文献   
175.
Oxidative cleavage of aromatic compounds is often part of a degradative process and is widely observed in nature. The immediate catabolic products can sometimes cyclize or rearrange to new secondary metabolites. The enzymatic contraction of a dehydroisocoumarin to yield cyclopentenoid metabolites in Cryptosporiopsis sp. is reported. The label distribution of (+) cryptosporiopsin, a chlorinated cyclopentenone, was determined by analysis of the [13C]nmr of [1-13C] and [2-13C]acetate enriched-cryptosporiopsin. The putative aromatic precursor of cyclopentenoid metabolites, 2,3-dihydro-6,8-dihydroxy-2-methylisocoumarin (6), was isolated from Aspergillus terreus. This metabolite (6) was prepared doubly labeled (T14C). The aromatic origin of the Cryptosporiopsis chlorinated cyclopentenoid metabolites was rigorously proven from feeding experiments with doubly labeled compound 6. A related but nonchlorinated metabolite, terrein, was isolated from A. terreus and was also shown to be derived from [T14C]-2,3-dihydro-6,8-dihydroxy-2-methylisocoumarin.  相似文献   
176.
Effect of Carbon Dioxide on Growth of Meat Spoilage Bacteria   总被引:8,自引:1,他引:7       下载免费PDF全文
The ability of CO2 to inhibit respiration and growth of representative strains of seven species of meat spoilage bacteria was examined. Enterobacter and Microbacterium thermosphactum were unaffected by CO2. Both respiration and growth of the other species were inhibited. With four of the species (fluorescent and nonfluorescent Pseudomonas, Alteromonas putrefaciens, and Yersinia enterocolitica), the inhibition pattern in a complex medium was similar, and inhibition was incomplete and reached a maximum level at comparatively low concentrations of CO2. With Acinetobacter, inhibition continued to increase with increasing CO2 concentration. The degree of inhibition with a constant concentration of CO2 in solution increased with decreasing temperature for all CO2-susceptible species except the nonfluorescent Pseudomonas. Anaerobic growth of CO2-susceptible facultative anaerobes was unaffected by CO2.  相似文献   
177.
When flax seedlings are decapitated above cotyledons and three days later one of the two cotyledons is removed then the remaining cotyledon stimulates in four to five days growth of its axillary bud. It has been found that content of endogenous cytokinins was higher in the stimulated bud as compared with the other one already 12 h after the cotyledon removal. Flax seedlings decapitated under cotyledons regenerate adventitious buds on thy hypocotyl stump during 5–6 days. The endogenous fytohormonal preparation of this regeneration was investigated in the 20 mm apical part of the hypocotyl stump. Decrease in auxin and increase in gibberellins was already found during the first day after decapitation while the level of cytokinins increased as late as three days after the apex removal.  相似文献   
178.
Using two-dimensional gel electrophoresis, we have identified two noncollagenous basement membrane (BM) glycopolypeptides which are synthesized by the mouse teratocarcinoma-derived parietal yolk sac (PYS) cell line. These glycopolypeptides have molecular weights of about 200,000 and isoelectric points of about 5.6. Polypeptides with identical parameters are synthesized by the parietal entodermal cells of mouse embryos and are found in Reichert's membrane. Pluripotent embryonal carcinoma cells (ECC) synthesize considerable amounts of the two polypeptides, whereas the yield from nullipotent ECC is negligible. The treatment of nullipotent F9 cells with retinoic acid, which induces entodermal differentiation, activates the synthesis of these polypeptides. These results indicate that the two polypeptides can be used as markers of parietal entoderm differentiation.  相似文献   
179.
We describe here three different hamster cell mutants which are resistant to diphtheria toxin and which provide models for investigating some of the functions required by the toxin inactivates elongation factor 2 (EF-2). Cell-free extracts from mutants Dtx(r)-3 was codominant. The evidence suggests that the codominant phenotype is the result of a mutation in a gene coding for EF-2. The recessive phenotype might arise by alteration of an enzyme which modifies the structure of EF-2 so that it becomes a substrate for reaction with the toxin. Another mutant, Dtx(r)-2, contained EF-2 that was sensitive to the toxin and this phenotype was recessive. Pseudomonas aeruginosa exotoxin is known to inactivate EF-2 as does diphtheria toxin and we tested the mutants for cross-resistance to pseudomonas exotoxin. Dtx(r)-1 and Dtx(r)-3 were cross-resistant while Dtx(r)-2 was not. It is known that diphtheria toxin does not penetrate to the cytoplasm of mouse cells and that these cell have a naturally occurring phenotype of diphtheria toxin resistance. We fused each of the mutants with mouse 3T3 cells and measured the resistance. We fused each of the mutants with mouse 3T3 cells and measured the resistance of the hybrid cells to diphtheria toxin. Intraspecies hybrids containing the genome of mutants Dtx(r)-1 and Dtx(r)-3 had some resistance while those formed with Dtx(r)-2 were as sensitive as hybrids derived from fusions between wild-type hamster cells and mouse 3T3 cells.  相似文献   
180.
[3H]Mepyramine binds with high affinity to membranes from brain of human, rat, guinea-pig, rabbit and mouse with drug specificity indicating an association with histamine H1receptors. Considerable species differences occur in the affinity of [3H]mepyramine, with guinea-pig and human having 34 times greater affinity than rat, mouse or rabbit. The greater affinity of [3H]mepyramine in guinea-pig than in rat is attributable both to faster association and slower dissociation rates in guinea-pig. Species differences in affinity for H1 receptor sites occur for some antihistamines but not for others. Some tricyclic antidepressant and neuroleptic drugs are extremely potent inhibitors of [3H]mepyramine binding, exceeding in potency any H1 antihistamines examined. The tricyclic antidepressant doxepin and the neuroleptic clozapine are the most potent of all drugs examined in competing for [3H]mepyramine binding. The regional distribution of specific [3H]mepyramine binding differs considerably in the various species examined.  相似文献   
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