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51.
Ecomorphological patterns of breeding dabbling duck (Anas spp.) assemblages were studied in six regions in northern Europe. Observed spacings among species in terms of bill lamellar density and body length were compared with expected spacings based on null models incorporating different levels of constraints (regional species pools, species relative abundances, lake size and habitat requirements of species). Deviations of observed spacings from expected ones were compared with prey abundance and prey size diversity in the lakes. Observed spacings in terms of body length, but not in terms of bill lamellar density, were greater than expected on the basis of null models. The most abundant species were generally relatively more different than less abundant species in terms of body length but not in terms of bill lamellar density. Deviations between observed and expected spacings in terms of body length were more like those predicted by the competition hypothesis in lakes with low food abundance than in lakes with high food abundance. Patterns in bill lamellar spacings were not related to food abundance nor to food size diversity. In general, patterns in body length spacings were consistent with the competition hypothesis whether the null model used in comparisons was constrained or not.  相似文献   
52.
Physiological responses to physical work were assessed for 29 female industrial sewing-machine operators during an 8-h working day under ordinary working conditions. During sewing-machine work, the average (left and right) static load in the trapezius muscle was 9% of the maximal electromyogram (EMG) amplitude (% EMGmax), while the average mean load was 15% EMGmax, and the average peak load was 23% EMGmax. The static load level was unrelated to the muscle strength of the sewing-machine operators, which for the group as a whole was within the normal range. The load levels remained unchanged during the working day, while changes in the EMG mean power frequency and zero crossing frequency rate occurred, both indicating the development of muscle fatigue in left and right trapezius muscle during the working day. In line with this, the rating of perceived exertion in the shoulder and neck region increased during. the working day. Dividing the group of sewing-machine operators into two groups, those with the highest frequency and those with the lowest frequency of shoulder/neck troubles showed that the former group had significantly lower muscle strength, despite the fact that no differences in the surface EMG during sewing were found between the two groups. It was concluded that industrial sewing-machine work involves a pattern of shoulder muscle activity which induces fatiguing processes in the shoulder and neck regions. Furthermore, since the static shoulder muscle load was independent of muscle strength, factors other than working posture may be of significance for the static shoulder muscle load.  相似文献   
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A porcine 2-kb partial dipeptidylpeptidase IV (DPP4, EC 3.4.14.5) cDNA clone and a porcine 16-kb genomic fragment containing parts of the DPP4 gene were isolated, characterized, and used as probes to map the DPP4 gene to pig Chr (Chr) 15q21 by fluorescence in situ hybridization. A two-allele RFLP was revealed for the DPP4 gene. This polymorphism was utilized in a linkage test against the erythrocyte antigen G (EAG), previously assigned to Chr 15, and the microsatellite S0088, which is linked to EAG. The linkage analyses revealed significant evidence for linkage confirming the assignment of DPP4 to Chr 15.  相似文献   
55.
OBJECTIVE--To identify factors that may predict long term psychological complications among women who have had a stillborn child. DESIGN--Nationwide population based study using epidemiological methods. SUBJECTS--380 subjects and 379 controls who had had a stillborn or non-deformed live child in Sweden in 1991. RESULTS--Information was provided by 636 (84%) women. The ratio (95% confidence interval) of proportions of women with symptoms related to anxiety above the 90th centile for women who had had a stillborn child compared with those who had not was 2.1 (1.2 to 3.9). An interval of 25 hours or more from the diagnosis of death in utero to the start of delivery gave a ratio of 4.8 (1.5 to 15.9). The ratio was 2.3 (1.1 to 5.3) for not seeing the child as long as the mother had wished and 3.1 (1.6 to 6.0) for no possession of a token of remembrance. CONCLUSION--It is advisable to induce the delivery as soon as feasible after the diagnosis of death in utero. A calm environment for the woman to spend as much time as she wants with her stillborn child is beneficial, and tokens of remembrance should be collected.  相似文献   
56.
Human aminopeptidase N is encoded by 20 exons   总被引:1,自引:0,他引:1  
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57.
Summary Earlier studies have shown anergy in chronic myeloid leukemia (CML), and it is known that myeloid cells influence lymphocyte responses. Therefore, lymphocytes from CML patients who had received no cytostatics for 2 weeks were stimulated in 89 tests with PHA and ConA. In 39 control tests, normal lymphocytes were used.Lymphocytes from CML patients were significantly less (p<0.05) markedly stimulated than normal ones. Lymphocytes from CML patients with more than 10×109 white blood cells (WBC) per liter blood were inhibited to a greater degree than those from patients with a normal WBC count.When normal lymphocytes were stimulated with PHA in the presence of mononuclear cells from the blood of CML patients (mostly leukemic myelocytes), their response was significantly (p<0.05) inhibited. Inhibition with leukemic myelocytes was significantly (p<0.05) greater than that with mature granulocytes from CML patients. The latter did not seem to have an inhibitory effect.We suggest that patients with manifest CML are anergic to some extent because leukemic myelocytes have a suppressor effect.Visiting scientist and Anna Villa Rusconi Fellow, on secondment from Institute of Medical Pathology, University of Ferrara, Italy  相似文献   
58.
Summary A partial alcohol dehydrogenase, ADH I, deficient mutant, GRF 18-2 of S. cerevisiae has been isolated. The mutant is resistant to allyl alcohol and the spec. activity of ADH I is 15-fold reduced in the mutant. In a batch fermentation the mutant overproduces glycerol. The production is enhanced 6–7 fold compared with the wildtype strain and it amounts to about 40 per cent of the ethanol produced. The yield of ethanol and glycerol is 56 and 24 per cent respectively. Another mutant possibly defect in the gene for ADH II has a reduced capacity to oxidize ethanol.  相似文献   
59.
Summary Experiments were performed to investigate growth, ethanol and glycerol production by wild-type strains (RHO) and respiratory-deficient (rho) mutants of Saccharomyces cerevisiae. Furthermore protoplasts were fused in order to enhance the fermentation capacity of a flocculent strain. At high substrate conditions, 150 g/l of saccharose, there is no difference in cell growth. However, at a glucose concentration of 10–20 g/l the mutants grow much slower. After 3 days of incubation at 28° C in a complete medium the viability of the two strains is the same. In minimal medium on the other hand the number of viable cells of the mutant is 100-fold reduced. All mutants tested showed a higher specific activity of alcohol dehydrogenase (ADH I) and an enhanced production of glycerol compared with the wild-type strain. By protoplast fusion a modified flocculent strain was obtained with higher specific activity of ADH I and a reduced biosynthesis of glycerol. However, the yields of ethanol (75–78%) are about the same for the wild-type strain and the rho mutants under aerobic conditions in absence of catabolite repression.  相似文献   
60.
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