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61.
Yersinia spp. were isolated from 34 of 500 birds representing nine species. The highest isolation rate, 5 of 21 (23.8%), was found in blue magpies (Cyanopia cyanus), followed by pheasants (Phasianus colchicus tohkaidi), 5 of 33 (15.2%); gray starlings (Sturnus cineraceus), 6 of 57 (10.5%); tree sparrows (Passer montanus), 1 of 14 (7.1%); bulbuls (Hypsipetes amaurotis), 4 of 57 (7.0%); crows (Corvus levailantii or Corvus corone), 7 of 117 (6.0%); eastern turtledoves (Streptopelia orientalis), 4 of 118 (3.4%); Chinese bamboo pheasants (Bumbusicola thoracica thoracica), 1 of 36 (2.8%); and domestic pigeons (Columba livia domestica), 1 of 47 (2.1%). The isolates were identified as Yersinia enterocolitica O:3, O:4, O:4,32, O:5A, O:6,30, O:7,8, and O:14, Yersinia frederiksenii, Yersinia intermedia, and Yersinia kristensenii. Yersinia spp. were isolated from 35 of 157 wild-living Japanese serows (Capricornis cripus). The isolates were identified as Y. enterocolitica O:4, O:4,32, O:5A, O:7, O:7,8, O:9, O:14, O:18, and O:34, Y. frederiksenii, Y. intermedia, and Y. kristensenii.  相似文献   
62.
One of the chitinases secreted in the culture filtrate of a gram-negative bacteria, Burkholderia cepacia strain KH2, which was isolated from the bed log of Lentinus edodes, Shiitake mushrooms, was purified by DEAE Sepharose CL-6B chromatography, followed by Sephacryl S-100 HR gel filtration. The purified enzyme was homogenous, determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), with an estimated molecular weight of 34,000 and an isoelectric point (pI) of 5.9. The enzyme was stable at pH values of 4.0-6.0, and at temperatures up to 50 degrees C; the optimum pH and temperature were 4.5 and 50 degrees C, respectively. The enzyme exhibited higher activities toward chitosan 7B, a 62% deacetylated chitosan, than toward the highly deacetylated chitosan substrates. The enzyme was observed to drastically hydrolyze partially deacetylated chitin substrates, with the subsequent formation of N-acetylchitooligosaccharides [(GlcNAc) (n), n=2-7]. Separation and quantification of the hydrolysis products of (GlcNAc) (n), n52-6, by HPLC showed the splitting into (GlcNAc)(n), n=3-6. Activity toward N-acetylchitobiose was not detected. Oligomers with a higher number of units than the starting substrate were also detected, which indicate transglycosylation activity.  相似文献   
63.
Q S Li  J Ogawa  R D Schmid  S Shimizu 《FEBS letters》2001,508(2):249-252
We report here oxidation of propylbenzene and 3-chlorostyrene by wild-type cytochrome P450 BM-3 with high turnover (479 nmol 1-phenyl-1-propanol/min/nmol P450 and 300 nmol 3-chlorostyrene oxide/min/nmol P450). Furthermore, the residue size at position 87 of P450 BM-3 was found to play critical roles in determining stereoselectivity in oxidation of propylbenzene and 3-chlorostyrene. Replacement of Phe87 with Val, Ala and Gly resulted in decreases in optical purity of produced (R)-(+)-1-phenyl-1-propanol from 90.0 to 37.4, 26.0 and -15.6% e.e., respectively, and in increases in those of produced (R)-(+)-3-chlorostyrene oxide from -61.0 to -38.0, 67.0 and 94.6% e.e., respectively.  相似文献   
64.
We examined the neuroprotective effects of oren-gedoku-to (TJ15), a herbal medicine, after transient forebrain ischemia. Transient forebrain ischemia was induced by occlusion of both common carotid arteries for 15 min in C57BL/6 mice treated with TJ15. In the control ischemic group without TJ15 treatment, histologic examination of brain tissue collected seven days after reperfusion showed death of pyramidal cells in CA2-3 area of the hippocampus, unilaterally or bilaterally. In mice treated with oral TJ15 (845 mg/kg/day) for five weeks, the frequency of ischemic neuronal death was significantly lower. Immunohistochemistry for Cu/Zn-superoxide dismutase (Cu/Zn-SOD) showed strongly reactive astrocytes in the hippocampus of ischemic mice treated with TJ15. Damage to nerve cells by free radicals plays an important role in the induction of neuronal death by ischemia-reperfusion injury. Our results suggest that TJ15 protects against ischemic neuronal death by increasing the expression of Cu/Zn-SOD and suggest that oren-gedoku-to reduces the exposure of hippocampal neurons to oxidative stress.  相似文献   
65.

Background

Early identification of ambulatory persons at high short-term risk of death could benefit targeted prevention. To identify biomarkers for all-cause mortality and enhance risk prediction, we conducted high-throughput profiling of blood specimens in two large population-based cohorts.

Methods and Findings

106 candidate biomarkers were quantified by nuclear magnetic resonance spectroscopy of non-fasting plasma samples from a random subset of the Estonian Biobank (n = 9,842; age range 18–103 y; 508 deaths during a median of 5.4 y of follow-up). Biomarkers for all-cause mortality were examined using stepwise proportional hazards models. Significant biomarkers were validated and incremental predictive utility assessed in a population-based cohort from Finland (n = 7,503; 176 deaths during 5 y of follow-up). Four circulating biomarkers predicted the risk of all-cause mortality among participants from the Estonian Biobank after adjusting for conventional risk factors: alpha-1-acid glycoprotein (hazard ratio [HR] 1.67 per 1–standard deviation increment, 95% CI 1.53–1.82, p = 5×10−31), albumin (HR 0.70, 95% CI 0.65–0.76, p = 2×10−18), very-low-density lipoprotein particle size (HR 0.69, 95% CI 0.62–0.77, p = 3×10−12), and citrate (HR 1.33, 95% CI 1.21–1.45, p = 5×10−10). All four biomarkers were predictive of cardiovascular mortality, as well as death from cancer and other nonvascular diseases. One in five participants in the Estonian Biobank cohort with a biomarker summary score within the highest percentile died during the first year of follow-up, indicating prominent systemic reflections of frailty. The biomarker associations all replicated in the Finnish validation cohort. Including the four biomarkers in a risk prediction score improved risk assessment for 5-y mortality (increase in C-statistics 0.031, p = 0.01; continuous reclassification improvement 26.3%, p = 0.001).

Conclusions

Biomarker associations with cardiovascular, nonvascular, and cancer mortality suggest novel systemic connectivities across seemingly disparate morbidities. The biomarker profiling improved prediction of the short-term risk of death from all causes above established risk factors. Further investigations are needed to clarify the biological mechanisms and the utility of these biomarkers for guiding screening and prevention. Please see later in the article for the Editors'' Summary  相似文献   
66.
67.
Novel thienopyrimidine compounds 2 and 3 were discovered from high-throughput screening as Natriuretic Peptide Receptor A (NPR-A) agonists. Scaffold hopping of a thienopyrimidine ring to a quinazoline ring, introduction of the basic functional group and optimization of the substituent on the 6-position of the benzene ring of quinazoline led to improved agonistic activity. We discovered compound 48, which showed potent agonistic activity for NPR-A with an EC50 value of 0.073 μM, indicating 350-fold potency compared to the hit compound 3.  相似文献   
68.
Airborne fungal spore concentrations in Szczecin, Poland, were studied between 2004 and 2006 with the objective of determining a seasonal variation in the concentrations of selected fungal spore types in relation to meteorological parameters. The presence of spores of five taxa, namely, Cladosporium, Ganoderma, Alternaria, Leptosphaeria and Didymella, was recorded using a volumetric method (Hirst type). Fungal spores were present in the air in large numbers during the summer, with the highest concentrations recorded mainly in June, July and August. The peak concentrations of two of the studied spore types, Ganoderma and Alternaria, occurred in August, while the concentrations of Cladosporium, Leptosphaeria and Didymella spores were the highest in July. Multiple regression analysis was performed for three fungal seasons—2004, 2005 and 2006. Spore concentration was found to be positively correlated with the minimum temperature. For some spore types, there was also a significant correlation between concentrations, relative humidity and rain.  相似文献   
69.
Mutant pqr-216 from an Arabidopsis activation-tagged line showed a phenotype of increased tolerance to oxidative stress after treatment with 3 μ m paraquat (PQ). Based on the phenotype of transgenic plants overexpressing the genes flanking the T-DNA insert, it was clear that enhanced expression of a Nudix (nucleoside diphosphates linked to some moiety X) hydrolase gene, AtNUDX2 (At5g47650), was responsible for the tolerance. It has been reported that the AtNUDX2 protein has pyrophosphatase activities towards both ADP-ribose and NADH ( Ogawa et al ., 2005 ). Interestingly, the pyrophosphatase activity toward ADP-ribose, but not NADH, was increased in pqr-216 and Pro 35S :AtNUDX2 plants compared with control plants. The amount of free ADP-ribose was lower in the Pro 35S :AtNUDX2 plants, while the level of NADH was similar to those in control plants under both normal conditions and oxidative stress. Depletion of NAD+ and ATP resulting from activation of poly(ADP-ribosyl)ation under oxidative stress was observed in the control Arabidopsis plants. Such alterations in the levels of these molecules were significantly suppressed in the Pro 35S :AtNUDX2 plants. The results indicate that overexpression of AtNUDX2 , encoding ADP-ribose pyrophosphatase, confers enhanced tolerance of oxidative stress on Arabidopsis plants, resulting from maintenance of NAD+ and ATP levels by nucleotide recycling from free ADP-ribose molecules under stress conditions.  相似文献   
70.
During the last decade, many strategies for cartilage engineering have been emerging. Stem cell induction is one of the possible approaches for cartilage engineering. The mesenchymal stem cells (MSCs) with their pluripotency and availability have been demonstrated to be an attractive cell source. It needs the stimulation with cell growth factors to make the multipluripotent MSCs differentiate into chondrogenic lineage. We have shown particular patterns of in vitro chondrogenesis induction on human bone marrow MSCs (hBMSCs) by cycling the growth factors. The pellet cultures of hBMSCs were prepared for chondrogenic induction. Growth factors: TGF-beta3, BMP-6, and IGF-1 were used in combination for cell induction. Gene expression, histology, immunohistology, and real-time PCR methods were measured on days 21 after cell induction. As shown by histology and immunohistology, the induced cells have shown the feature of chondrocytes in their morphology and extracellular matrix in both inducing patterns of combination and cycling induction. Moreover, the real-time PCR assay has shown the expression of gene markers of chondrogenesis, collagen type II and aggrecan. This study has demonstrated that cartilage tissue can be created from bone marrow mesenchymal stem cells. Interestingly, the combined growth factors TGF-beta3 and BMP-6 or TGF-beta3 and IGF-1 were more effective for chondrogenesis induction as shown by the real-time PCR assay. The combination of these growth factors may be the important key for in vitro chondrogenesis induction.  相似文献   
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