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871.
A novel series of 9-O-arylpropenyloxime ketolide was synthesized and evaluated for their antibacterial activity. This series of ketolide exhibited potent activity against clinically isolated gram-positive strains including Staphylococcus pneumoniae and Straptococcus Pyogenes.  相似文献   
872.
Helping behaviour in cooperative breeding systems has been attributed to kin selection, but the relative roles of direct and indirect fitness benefits in the evolution of such systems remain a matter of debate. In theory, helpers could maximize the indirect fitness benefits of cooperation by investing more in broods with whom they are more closely related, but there is little evidence for such fine-scale adjustment in helper effort among cooperative vertebrates. In this study, we used the unusual cooperative breeding system of the long-tailed tit Aegithalos caudatus to test the hypothesis that the provisioning effort of helpers was positively correlated with their kinship to broods. We first use pedigrees and microsatellite genotypes to characterize the relatedness between helpers and breeders from a 14 year field study. We used both pedigree and genetic approaches because long-tailed tits have access to pedigree information acquired through social relationships, but any fitness consequences will be determined by genetic relatedness. We then show using both pedigrees and genetic relatedness estimates that alloparental investment by helpers increases as their relatedness to the recipients of their care increases. We conclude that kin selection has played a critical role in moulding the investment decisions of helpers in this cooperatively breeding species.  相似文献   
873.
A new series of 2,4-diphenyl-6-aryl pyridines containing hydroxyl group(s) at the ortho, meta, or para position of the phenyl ring were synthesized, and evaluated for topoisomerase I and II inhibitory activity and cytotoxicity against several human cancer cell lines for the development of novel anticancer agents. Structure–activity relationship study revealed that the substitution of hydroxyl group(s) increased topoisomerase I and II inhibitory activity in the order of meta > para > ortho position. Substitution of hydroxyl group on the para position showed better cytotoxicity.  相似文献   
874.
875.

Background  

A new image-resizing method using seam carving and a Saliency Strength Map (SSM) is proposed to preserve important contents, such as white blood cells included in blood cell images.  相似文献   
876.
Cho SJ  Choi IJ  Kim CG  Kook MC  Lee JY  Kim BC  Ryu KH  Nam SY  Kim YW 《Helicobacter》2010,15(6):516-523
Background: Although gastric cancer (GC) and duodenal ulcer (DU) are both strongly associated with Helicobacter pylori infection, a DU is negatively associated with the risk of GC. The aim of the study is to evaluate histologic risk factors for GC among patients with a DU. Materials and Methods: A total of 541 consecutive patients with GC were prospectively evaluated for the presence of a DU. Control patients with only a DU (n = 89) were recruited from health screening population. Histologic grading was assessed using the updated Sydney system for six gastric biopsies from three regions. GC risk among patients with a DU was evaluated using logistic regression analysis. Results: Among patients with GC, 7.6% (41/541) had a concomitant DU or an ulcer scar. Corpus‐predominant/pangastritis were more frequently found in concomitant GC patients with a DU (90%) than in patients with a DU alone (62%) (p = .001). In patients with a DU, moderate–severe chronic inflammation at the lesser and greater curvatures of corpus was associated with GC risk (OR, 3.70; 95% CI, 1.46–9.36, and OR, 7.72; 95% CI, 3.18–18.7, respectively). Additionally, moderate–severe intestinal metaplasia (IM) at the antrum and corpus lesser curvature was associated with GC risk (OR, 7.52; 95% CI, 3.06–18.5, and OR, 9.25, 95% CI, 2.39–35.8, respectively). Conclusions: A DU is not rare in patients with GC in a high‐risk region of GC. Patients with a DU with chronic corpus gastritis and IM have an increased risk of GC, thus those patients should be followed up for GC development.  相似文献   
877.
A moderate halophile, strain X50T, was isolated from mustard kimchi, a traditional Korean fermented food. The organism grew under conditions ranging from 0–15.0% (w/v) NaCl (optimum: 3.0%), pH 7.0–10.0 (optimum: pH 9.0) and 15–45°C (optimum: 37°C). The morphological, physiological, and biochemical features and the 16S rRNA gene sequences of strain X50T were characterized. Colonies of the isolate were creamcolored and the cells were rod-shaped. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain X50T belongs to the genus Oceanobacillus and is closely related phylogenetically to the type strain O. iheyensis HTE831T (98.9%) and O. oncorhynchi subsp. oncorhynchi R-2T (97.0%). The cellular fatty acid profiles predominately included anteiso-C15:0 and iso-C15:0. The G+C content of the genomic DNA of the isolate was 37.9 mol% and the major isoprenoid quinone was MK-7. Analysis of the 16S rRNA gene sequences, DNA-DNA relatedness and physiological and biochemical tests indicated genotypic and phenotypic differences among strain X50T and reference species in the genus Oceanobacillus. Therefore, strain X50T was proposed as a novel species and named Oceanobacillus kimchii. The type strain of the new species is X50T (=JCM 16803T =KACC 14914T =DSM 23341T).  相似文献   
878.
The use of high purity oxygen as a feeding gas in microbial fermentation has recent gained huge attention in industrial scale process due to its advantageous effect to increase viable cell density as well as target metabolite productivity. However, usage of highly pure oxygen is currently too expensive for industrialization. To overcome this limitation, off-gas recycle pressure swing adsorption (PSA) was employed which assist in continuous production of high purity oxygen during fermentation process. The off-gas from fermentation process contained about 70 ∼ 80% oxygen which was re-utilized as the input gas in PSA, whereas conventional PSA process utilized air with 21% oxygen content. This difference in the oxygen content of the input gas decreased the size of PSA, resulting in reduction of equipment costs. Using the characteristics of off-gas recycle PSA, we analyzed and compared the economic feasibility of a highly pure oxygen supplying strategy for the production of poly(3-hydroxybutyrate) (PHB) by Ralstonia eutropha based on previously reported data, using both air and highly pure oxygen. To achieve annual production of 3,630 tonnes of PHB the aforementioned method was adopted, by doing so the production cost of PHB was significantly reduced to 4.2 /kg. While, the conventional process (utilizing air as the feeding gas) resulted in the highest cost (5.9/kg. While, the conventional process (utilizing air as the feeding gas) resulted in the highest cost (5.9 /kg). The low cost of off-gas recycle PSA was due to reduction of fixed capital cost, which was about 3 times lower than that of the conventional fermentation process. Therefore, the production cost of fermentation was considerably decreased by using a highly pure oxygen supplying strategy based on off-gas recycle PSA.  相似文献   
879.
Given the substantial rise in obesity, depot-specific fat accumulation and its associated diseases like diabetes, it is important to understand the molecular basis of depot-specific adipocyte differentiation. Many studies have successfully exploited the adipocyte differentiation, but most of them were not related to depot-specificity, particularly using freshly isolated primary preadipocytes. Using 2-dimensional polyacrylamide gel electrophoresis coupled with sequencing mass spectrometry, we searched and compared the proteins differentially expressed in undifferentiated and differentiated preadipocytes from bovine omental, subcutaneous and intramuscular adipose depots. Our proteome mapping strategy to identify differentially expressed intracellular proteins during adipogenic conversion revealed 65 different proteins that were found to be common for the three depots. Further, we validated the differential expression for a subset of proteins by immunoblotting analyses. The results demonstrated that many structural proteins were down-regulated during differentiation of preadipocytes from all the depots. Most up-regulated proteins like Ubiquinol–cytochrome-c reductase complex core protein I (UQCRC1), ATP synthase D chain, Superoxide dismutase (SOD), Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), Sulfotransferase 1A1 (SULT1A1), Carnitine O-palmitoyltransferase 2 (CPT2) and Heat-shock protein beta 1 (HSPB1) across the three depots were found to be associated with lipid metabolism and metabolic activity. Further, all the up-regulated proteins were found to have higher protein expression in omental than subcutaneous or intramuscular depots.  相似文献   
880.

Background

Dengue is a major global public health problem with increasing incidence and geographic spread. The epidemiology is complex with long inter-epidemic intervals and endemic with seasonal fluctuations. This study was initiated to investigate dengue transmission dynamics in Binh Thuan province, southern Vietnam.

Methodology

Wavelet analyses were performed on time series of monthly notified dengue cases from January 1994 to June 2009 (i) to detect and quantify dengue periodicity, (ii) to describe synchrony patterns in both time and space, (iii) to investigate the spatio-temporal waves and (iv) to associate the relationship between dengue incidence and El Niño-Southern Oscillation (ENSO) indices in Binh Thuan province, southern Vietnam.

Principal Findings

We demonstrate a continuous annual mode of oscillation and a multi-annual cycle of around 2–3-years was solely observed from 1996–2001. Synchrony in time and between districts was detected for both the annual and 2–3-year cycle. Phase differences used to describe the spatio-temporal patterns suggested that the seasonal wave of infection was either synchronous among all districts or moving away from Phan Thiet district. The 2–3-year periodic wave was moving towards, rather than away from Phan Thiet district. A strong non-stationary association between ENSO indices and climate variables with dengue incidence in the 2–3-year periodic band was found.

Conclusions

A multi-annual mode of oscillation was observed and these 2–3-year waves of infection probably started outside Binh Thuan province. Associations with climatic variables were observed with dengue incidence. Here, we have provided insight in dengue population transmission dynamics over the past 14.5 years. Further studies on an extensive time series dataset are needed to test the hypothesis that epidemics emanate from larger cities in southern Vietnam.  相似文献   
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