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991.
992.
Objectives To assess the effect of self monitoring of blood glucose concentrations on glycaemic control and psychological indices in patients with newly diagnosed type 2 diabetes mellitus.Design Prospective randomised controlled trial of self monitoring versus no monitoring (control).Setting Hospital diabetes clinics.Participants 184 (111 men) people aged <70 with newly diagnosed type 2 diabetes referred to the participating diabetes clinics. Major exclusion criteria were secondary diabetes, insulin treatment, previous self monitoring of blood glucose.Interventions Participants were randomised to self monitoring or no monitoring (control) groups for one year with follow-up at three monthly intervals. Both groups underwent an identical structured core education programme. The self monitoring group received additional education on monitoring.Main outcome measures Between group differences in HbA1c, psychological indices, use of oral hypoglycaemic drugs, body mass index (BMI), and reported hypoglycaemia rates.Results 96 patients (55 men) were randomised to monitoring and 88 (56 men) to control. There were no baseline differences in mean (SD) age (57.7 (11.0) in monitoring group v 60.9 (11.5) in control group) or HbA1c (8.8 (2.1)% v 8.6 (2.3)%, respectively). Those in the monitoring group had a higher baseline BMI (34 (7) v 32 (6.2)). There were no significant differences between groups at any time point (12 months values given) in HbA1c (6.9 (0.8)% v 6.9 (1.2)%, P=0.69; 95% confidence interval for difference −0.25% to 0.38%), BMI (33.1 (6.4) v 31.8 (6.0); adjusted for baseline BMI, P=0.32), use of oral hypoglycaemic drugs, or reported incidence of hypoglycaemia. Monitoring was associated with a 6% higher score on the depression subscale of the well-being questionnaire (P=0.01).Conclusions In patients with newly diagnosed type 2 diabetes self monitoring of blood glucose concentration has no effect on glycaemic control but is associated with higher scores on a depression subscale.Trial registration ISRCTN 49814766.  相似文献   
993.
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995.
Summary We conducted experiments to assess the importance of winter cold and photoperiod as factors affecting the spatial and age distributions of overwintering larvae of the treehole mosquito Anopheles barberi. Larval dormancy in A. barberi was induced by photoperiods with 14.75 h of light or less per 24 h cycle. About 75% of the larvae entering dormancy were in the second instar regardless of photoperiod. Dormant second instar larvae survived freezing at-15° C for 24 h better than dormant third instar larvae. Larvae were more likely to survive freezing at-15° C in water from treeholes in which they were commonly found in nature than in water from treeholes in which they were unlikely to occur. Female oviposition was significantly higher into water from treeholes in which larvae were likely to be found than in either water from treeholes in which larvae were not commonly found or distilled water. These findings suggest that, in the northern part of its range, the distribution of A. barberi and the age structure of overwintering cohorts are influenced by extreme winter cold. The mechanisms responsible for the distribution of larvae and the overwintering age structure are, respectively, female oviposition behavior and larval photoperiodism.  相似文献   
996.
(E)-4-Hydroxy-2-nonenal (HNE), a cytotoxic end-product of lipid peroxidation, is present in significant amounts in human semen (0.902 +/- 0.190 microM; mean +/- s.e.; n = 18). The addition of the divalent cation ionophore A23187 to suspensions of human spermatozoa resulted in increased production of HNE. Exogenous HNE was powerfully spermicidal and as little as 50 microM caused an irreversible loss of motility of human spermatozoa within minutes. The addition of human seminal plasma protected spermatozoa from the toxic effects of HNE.  相似文献   
997.
The Saccharomyces cerevisiae Spo11 protein is thought to catalyze formation of the DNA double-strand breaks that initiate meiotic recombination. We have cloned cDNA and genomic DNA for a mouse gene encoding a protein with significant sequence similarity to conserved domains found in proteins of the Spo11p family. This putative mouse Spo11 gene maps to the distal region of chromosome 2 (homologous to human chromosome 20q13.2-q13.3) and comprises at least 12 exons, spanning approximately 15-18 kb. Strong expression of the Spo11 message is seen in juvenile and adult testis by RNA in situ hybridization, RT-PCR, and Northern blot, with much weaker expression in thymus and brain. In situ hybridization detects expression in oocytes of embryonic ovary, but not of adult ovary. RT-PCR and in situ hybridization analyses of a time course of juvenile testis development indicate that Spo11 expression begins in early meiotic Prophase I, prior to the pachytene stage, with increasing accumulation of mRNA through the pachytene stage. Taken together, these results strongly suggest that this gene encodes the functional homolog of yeast Spo11p, which in turn suggests that the mechanism of meiotic recombination initiation is conserved between yeast and mammals.  相似文献   
998.
The authors have previously observed that glucocorticoids dramatically increase the number of interleukin 1 (IL-1) receptors on normal human peripheral blood mononuclear cells (PBMC) (from approximately 100 to 2000 receptors/cell) without significant change in the binding affinity (Kd = approximately 2.6 x 10(-10) M). We, therefore, used such a receptor-enriched glucocorticoid-pretreated PBMC to investigate whether IL-1 induces/increases the phosphorylation of any cell-associated proteins, including possible autophosphorylation of IL-1 receptors. Extraction of 125I-labeled IL-1 alpha cross-linked to IL-1 receptor on steroid-treated PBMC yielded two bands estimated to be 60 and 70 kDa in molecular mass. No molecules were significantly cross-linked with 125I-labeled IL-1 alpha on untreated PBMC. Carrier-free recombinant human IL-1 alpha induced phosphorylation of an acidic 65-kDa protein (pp65) at serine residues within 5 min more effectively in glucocorticoid-treated PBMC than in untreated PBMC. Fractionation of extracts of IL-1-stimulated prednisolone-pretreated PBMC by ultracentrifugation showed that pp65 is located in the cytosol, suggesting that pp65 is not the IL-1 receptor itself. Protein kinase inhibitors, HA1004 and W-7, but not H-7, significantly inhibited the induction of the phosphorylation of 65-kDa protein by IL-1. These data indicate that the glucocorticoid-induced IL-1 receptor is functional and either contains or is closely associated with a serine kinase that is distinct from protein kinase C.  相似文献   
999.
Synthetic non-peptide inhibitors of HIV protease   总被引:3,自引:0,他引:3  
We have studied the inhibition of HIV protease by the antifungal antibiotic cerulenin, as well as by several related synthetic, structurally simpler analogs. The effect of these compounds on HIV protease was conveniently studied by monitoring the cleavage of an authentic single peptide bond in a synthetic nonapeptide corresponding to a natural cleavage site in HIV-1 gag precursor polyprotein. The relative inhibitory effects of these compounds have afforded an insight into the structural characteristics which impart antiprotease activity.  相似文献   
1000.
This study was undertaken to assess the nature of somatomedin-C (SM-C) in baboon (Papio cynocephalus) blood and to compare various methods for estimating SM-C concentrations. Parallel dose-response curves were obtained with normal baboon serum, normal human serum, and purified SM-C. Recovery of purified SM-C added to baboon serum over a wide dosage range (n = 17) was 111 ± 12%, with slightly better recovery at higher potencies. Chromatography of normal baboon serum on Sephadex G-200 at neutral pH produced a profile similar to that observed in the human, as did samples chromatographed on Sephadex G-50 in acid. Although the SM-C content in acid chromatographed plasma was approximately 2.5 times higher than in native unprocessed plasma, there was excellent correlation between the values (r = 0.9143, p < 0.0001). The SM-C in baboon plasma which had been preincubated with glycine HCl was approximately twice that of unprocessed plasma, but the correlation between the two methods was excellent (r = 0.9593, p < 0.0001). The correlation between values obtained after simple acid-ethanol extraction and those observed in unextracted plasma were also significant (r = 0.7689, p < 0.0001). Following a series of four injections of human growth hormone (hGH) to a normal baboon, plasma SM-C rose approximately sevenfold above the initial concentration and returned to basal levels five days after the final injection. These studies show that although the radioimmunoassay (RIA) for SM-C in unprocessed baboon plasma does not measure all of the SM-C present, it provides a reliable index of the total SM-C concentration and reflects GH status in the baboon.  相似文献   
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