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991.
According to fossil data, the wood mouse arrived in North Africa 7500 ya, while it was present in Europe since Early Pleistocene. Previous molecular studies suggested that its introduction in North Africa probably occurred via the Strait of Gibraltar more than 0.4 Mya ago. In this study, we widely sampled wood mice to get a better understanding of the geographic and demographic history of this species in North Africa and possibly to help resolving the discrepancy between genetic and palaeontological data. Specifically, we wanted to answer the following questions: (1) When and how did the wood mouse arrive in North Africa? and (2) What is its demographic and geographic history in North Africa since its colonization? We collected in the field 438 new individuals and used both mtDNA and six microsatellite markers to answer these questions. Our results confirm that North African wood mice have a south‐western European origin and colonized the Maghreb through the Strait of Gibraltar probably during the Mesolithic or slightly after. They first colonized the Tingitana Peninsula and then expanded throughout North Africa. Our genetic data suggest that the ancestral population size comprised numerous individuals reinforcing the idea that wood mice did not colonize Morocco accidentally through rafting of a few individuals, but via recurrent/multiple anthropogenic translocations. No spatial structuring of the genetic variability was recorded in North Africa, from Morocco to Tunisia.  相似文献   
992.
Red emission intensity was optimized in three stages, by investigating the effects of: (i) host composition (Gd, Y and Gd/Y), (ii) codoping Li+ as a sensitizer and, finally, (iii) with a SiO2 shell coating as a protecting layer. Lanthanide vanadate powder phosphors were synthesized using a modified colloidal precipitation technique. The effects of SiO2 coating on phosphor particles were characterized using scanning electron microscopy (SEM)‐EDAX, transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and photoluminescence (PL) measurements. An improvement in the PL intensity on Li codoping was due to improved crystallinity, which led to higher oscillating strengths for the optical transitions, and also a lowering of the inversion symmetry of Eu3+ ions. Red emission intensity due to 5D05D2 transition of the phosphor Y0.94VO4:Eu3+0.05,Li+0.01 was enhanced by 22.28% compared with Y0.95VO4:Eu3+0.05, and was further improved by 58.73% with SiO2 coating. The luminescence intensity (I) and colour coordinates (x, y) of the optimized phosphor Y0.94VO4:Eu3+0.05,Li+0.01@SiO2, where I = 13.07 cd/m2 and (x = 0.6721, y = 0.3240), were compared with values for a commercial red phosphor (Y2O2S:Eu3+), where I = 27 cd/m2 and (x = 0.6522, y = 0.3437). The measured colour coordinates are superior to those of the commercial red phosphor, and moreover, match well with standard NTSC values (x = 0.67, y = 0.33). Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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Thirty new aryl-pyridazinone-substituted benzenesulphonylurea derivatives (IXXX) were synthesized and evaluated for their anti-hyperglycaemic activity in glucose-fed hyperglycaemic normal rats. Twenty-three compounds (IIIXI, XIVXVII, XIXXXIV, XXVI and XXVIIIXXX) showed more or comparable area under the curve (AUC) reduction percentage (ranging from 21.9% to 35.5%) as compared to the standard drug gliclazide (22.0%). On the basis of docking results, 18 compounds were screened for their in vitro ability to inhibit rat lens aldose reductase. Ten compounds (IIIVI, XII, XVIXVIII, XXI and XXVII) showed ARI activity with IC50 ranging from 34 to 242?μM. Out of these, two compounds IV and V showed best ARI activity which is comparable with that of quercetin. As a result, two compounds (IV and V) possessing significant dual action (anti-hyperglycaemic and aldose reductase inhibition) were identified and may be used as lead compounds for developing new drugs.  相似文献   
995.
Seasonal incidence of aphid, Amphorophora ampullata on Hypolepis polypodioides was recorded throughout the year from November 2012 to November 2013 at weekly interval. Peak incidence of aphid was recorded during third week of November 2012 (25.94 ± 2.39 aphids/pinna), later the aphid population gradually decreased from December 2012 onwards and reached below threshold level during the last week of January (0.1 ± 0 aphids/pinna). The aphid population starts building up again from first week of February 2013 (1.6 ± 0.13 aphids/pinna) and attained its peak in the last week of August (32.17 ± 1.22 aphids/pinna) then decreased gradually in the first week of September (20.82 ± 4.70 aphids/pinna). Aphid densities again increased gradually from second week of September (21.62 ± 3.02 aphids/pinna) to November 2013 and reached maximum aphid densities during November (56.55 ± 4.34 aphids/pinna). Among weather parameters, aphid population showed significant positive correlation with relative humidity during morning hours.  相似文献   
996.
Brassica juncea is an economically important oilseed crop worldwide. It has limited genomic resources at present. We generated 47,962,057 expressed sequence reads which were assembled into 45,280 unigenes. A total of 4108 SSR loci (≥10 bp) were identified in these unigenes. Trinucleotide was the most frequent repeat unit (59.91 %) followed by di- (38.66 %), tetra - (0.71 %), hexa - (0.49 %) and pentanucleotide repeats (0.24 %). Primers were designed for 2863 SSR loci among which 460 were selected for primer synthesis. A total of 339 loci amplified successfully of which 134 (39.5 %) exhibited polymorphism among six B. juncea genotypes with PIC values ranging from 0.18 to 0.81. Further, 25 polymorphic SSRs were used for analysis of genetic variability in 25 genotypes of Brassicas and their wild relatives. Two to five alleles with PIC values 0.22–0.66 were detected at these loci. The dendrogram grouped the genotypes according to their known pedigree/systematic position.  相似文献   
997.
Soil pollution is a major environmental problem and many contaminated sites are tainted with a mixture of organic and heavy metal contaminants. Compared to other remedial strategies, phytoremediation is a low cost, environmentally-friendly, sustainable means of remediating the contamination. This review first provides an overview of phytoremediation studies where the soil is contaminated with just one type of pollutant (heavy metals or organics) and then critically evaluates the applicability of phytotechnologies for the remediation of contaminated sites where the soil is polluted by a mixture of organic and heavy metal contaminants. In most of the earlier research studies, mixed contamination was held to be detrimental to plant growth, yet there were instances where plant growth was more successful in soil with mixed contamination than in the soil with only individual contaminants. New effective phytoremediation strategies can be designed for remediation of co-contaminated sites using: (a) plants species especially adapted to grow in the contaminated site (hyperacumulators, local plants, transgenic plants); (b) endophytic bacteria to enhance the degradation in the rizhosphere; (c) soil amendments to increase the contaminants bioavailability [chelating agents and (bio)surfactants]; (d) soil fertilization to enhance the plant growth and microbial activity in the soil; and (e) coupling phytoremediation with other remediation technologies such as electrokinetic remediation or enhanced biodegradation in the rhizosphere.  相似文献   
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999.
1000.

Background

Despite the introduction of direct-acting antiviral agents for chronic hepatitis C virus (HCV) infection, peginterferon alfa/ribavirin remains relevant in many resource-constrained settings. The non-randomized GUARD-C cohort investigated baseline predictors of safety-related dose reductions or discontinuations (sr-RD) and their impact on sustained virologic response (SVR) in patients receiving peginterferon alfa/ribavirin in routine practice.

Methods

A total of 3181 HCV-mono-infected treatment-naive patients were assigned to 24 or 48 weeks of peginterferon alfa/ribavirin by their physician. Patients were categorized by time-to-first sr-RD (Week 4/12). Detailed analyses of the impact of sr-RD on SVR24 (HCV RNA <50 IU/mL) were conducted in 951 Caucasian, noncirrhotic genotype (G)1 patients assigned to peginterferon alfa-2a/ribavirin for 48 weeks. The probability of SVR24 was identified by a baseline scoring system (range: 0–9 points) on which scores of 5 to 9 and <5 represent high and low probability of SVR24, respectively.

Results

SVR24 rates were 46.1% (754/1634), 77.1% (279/362), 68.0% (514/756), and 51.3% (203/396), respectively, in G1, 2, 3, and 4 patients. Overall, 16.9% and 21.8% patients experienced ≥1 sr-RD for peginterferon alfa and ribavirin, respectively. Among Caucasian noncirrhotic G1 patients: female sex, lower body mass index, pre-existing cardiovascular/pulmonary disease, and low hematological indices were prognostic factors of sr-RD; SVR24 was lower in patients with ≥1 vs. no sr-RD by Week 4 (37.9% vs. 54.4%; P = 0.0046) and Week 12 (41.7% vs. 55.3%; P = 0.0016); sr-RD by Week 4/12 significantly reduced SVR24 in patients with scores <5 but not ≥5.

Conclusions

In conclusion, sr-RD to peginterferon alfa-2a/ribavirin significantly impacts on SVR24 rates in treatment-naive G1 noncirrhotic Caucasian patients. Baseline characteristics can help select patients with a high probability of SVR24 and a low probability of sr-RD with peginterferon alfa-2a/ribavirin.  相似文献   
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