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991.
BackgroundHospitalized preterm infants with compromised skin barrier function treated topically with sunflower seed oil (SSO) have shown reductions in sepsis and neonatal mortality rate (NMR). Mustard oil and products commonly used in high-mortality settings may possibly harm skin barrier integrity and enhance risk of infection and mortality in newborn infants. We hypothesized that SSO therapy may reduce NMR in such settings.Methods and findingsThis was a population-based, cluster randomized, controlled trial in 276 clusters in rural Uttar Pradesh, India. All newborn infants identified through population-based surveillance in the study clusters within 7 days of delivery were enrolled from November 2014 to October 2016. Exclusive, 3 times daily, gentle applications of 10 ml of SSO to newborn infants by families throughout the neonatal period were recommended in intervention clusters (n = 138 clusters); infants in comparison clusters (n = 138 clusters) received usual care, such as massage practice typically with mustard oil. Primary analysis was by intention-to-treat with NMR and post-24-hour NMR as the primary outcomes. Secondary analysis included per-protocol analysis and subgroup analyses for NMR. Regression analysis was adjusted for caste, first-visit weight, delivery attendant, gravidity, maternal age, maternal education, sex of the infant, and multiple births. We enrolled 13,478 (52.2% male, mean weight: 2,575.0 grams ± standard deviation [SD] 521.0) and 13,109 (52.0% male, mean weight: 2,607.0 grams ± SD 509.0) newborn infants in the intervention and comparison clusters, respectively. We found no overall difference in NMR in the intervention versus the comparison clusters [adjusted odds ratio (aOR) 0.96, 95% confidence interval (CI) 0.84 to 1.11, p = 0.61]. Acceptance of SSO in the intervention arm was high at 89.3%, but adherence to exclusive applications of SSO was 30.4%. Per-protocol analysis showed a significant 58% (95% CI 42% to 69%, p < 0.01) reduction in mortality among infants in the intervention group who were treated exclusively with SSO as intended versus infants in the comparison group who received exclusive applications of mustard oil. A significant 52% (95% CI 12% to 74%, p = 0.02) reduction in NMR was observed in the subgroup of infants weighing ≤1,500 g (n = 589); there were no statistically significant differences in other prespecified subgroup comparisons by low birth weight (LBW), birthplace, and wealth. No severe adverse events (SAEs) were attributable to the intervention. The study was limited by inability to mask allocation to study workers or participants and by measurement of emollient use based on caregiver responses and not actual observation.ConclusionsIn this trial, we observed that promotion of SSO therapy universally for all newborn infants was not effective in reducing NMR. However, this result may not necessarily establish equivalence between SSO and mustard oil massage in light of our secondary findings. Mortality reduction in the subgroup of infants ≤1,500 g was consistent with previous hospital-based efficacy studies, potentially extending the applicability of emollient therapy in very low-birth-weight (VLBW) infants along the facility–community continuum. Further research is recommended to develop and evaluate therapeutic regimens and continuum of care delivery strategies for emollient therapy for newborn infants at highest risk of compromised skin barrier function.Trial registrationISRCTN Registry ISRCTN38965585 and Clinical Trials Registry—India (CTRI/2014/12/005282) with WHO UTN # U1111-1158-4665.

In a cluster randomized trial, Aarti Kumar and colleagues study the effectiveness of a topical sunflower seed oil therapy in reducing neonatal mortality in Uttar Pradesh, India.  相似文献   
992.
This study was conducted through the pot experiments to understand the mechanism of lead (Pb) and arsenic (As)-induced phytotoxicity and their possible alleviation by glutathione (GSH) and citric acid (CA) in two cultivars of Solanum lycopersicum L., i.e., Pusa ruby (PR) and Arka vikas (S22). Therefore, tomato seedlings were germinated in soil-rite supplemented with seven treatments, i.e., control, 10 µM Pb, 10 µM As, 10 µM Pb + 250 µM GSH, 10 µM As + 250 µM GSH, 10 µM Pb + 250 µM CA and 10 µM As + 250 µM CA for 7 days and examined for growth parameters, lipid peroxidation, photosynthetic pigments and antioxidative mechanism. Results of our study showed that Pb and As alone decrease seed germination, growth parameter, chlorophylls and increase anthocyanins and lipid peroxidation in both the cultivars. Pb- and As-induced oxidative stress resulted into significant changes in the plant responses that attributed by increased activity of antioxidative enzymes and non-enzymatic antioxidants. GSH and CA showed potential to alleviate Pb- or As-induced phytotoxicity and strengthen the plant antioxidative machinery and structural integrity. Cultivar PR showed better response than cv. S22. Pb and As treatment caused significant damages to the DNA molecules and structural integrity of the cv. PR roots. These findings can be useful for understanding the Pb- and As-induced phytotoxic biomarkers along with GSH- and CA-mediated alleviation mechanisms, which will provide new insight in developing better system for phytoremediation technology.  相似文献   
993.
Root‐nodulating bacteria are intimate associates of legumes. From a pool of rhizobia isolated from root nodules of Mucuna pruriens (Velvet bean/Kaunch), RMP66 and BMP17 were found to be capable of promoting siderophore and IAA production and phosphate solubilization (insoluble tri‐calcium). Both symbionts were studied further to determine their abilities to promote plant growth and to control root‐rot in Mucuna pruriens caused by the pathogenic plant fungus Macrophomina phaseolina. RMP66 and BMP17 were selected based on their excellent inhibitory activities against M. phaseolina (by 78% and 71%, respectively) in dual culture and in agar‐well assays using cell‐free culture filtrate (CFCF) (by 76% and 62%, respectively). Both strains inhibited fungal growth to a greater extent in iron‐deficient medium (51% and 69%) than in iron‐supplemented medium (37% and 0%), respectively. CFCFs of RMP66 and BMP17 obtained from Pikovskaya's broth and tryptophan‐amended YEM broth inhibited fungal growth by 80%‐55% and 70%‐43%, respectively, and were identified as Sinorhizobium meliloti RMP66 and Bradyrhizobium diazoefficiens BMP17 by 16S rDNA sequencing. Centrifuged and pelleted cells harvested from exponentially grown cultures of Smeliloti RMP66 and Bdiazoefficiens BMP17 were used to bacterize seeds of M. pruriens, which then showed enhanced seed germination (by up to 17% and 12%, respectively), and subsequent increases in other plant growth parameters in field trials. Considerable increases in seedling vigour indices (62%: 53% and 110%: 130%) and biomass (8%: 13% and 25%: 28%) were also observed for bacterial treatments. Tn5‐mediated antibiotic‐resistant marker strains showed enhanced nodule occupancy by up to 72% and 68%, respectively. This study describes a multifunctional legume nodule rhizobia that could be utilized in multicropping systems under different agroclimatic conditions as a bioinoculant and alternative to fertilizers.  相似文献   
994.
Knoevenagel cyclocondensations of α-hydroxy naphthaldehyde with β-oxodithioesters and ketene dithioacetals yielded 2H-benzo[f]chromene-2-thiones and 2H-benzo[f]chromen-2-ones, respectively, in high yields. The newly synthesized compounds were evaluated for antifungal and antibacterial activities. Among them, compounds (2-furyl)(3-thioxo-3H-benzo[f]chromen-2-yl)methanone and phenyl(3-oxo-3H-benzo[f]chromen-2-yl)methanone exhibited excellent antifungal activity against tested fungi Curvularia lunata and Fusarium moniliforme. The highest antibacterial activity against the tested bacteria Escherichia coli and Staphylococcus aureus was observed for (4-chlorophenyl)(3-oxo-3H-benzo[f]chromen-2-yl)methanone. The results of antimicrobial screening demonstrate that (2-furyl)(3-thioxo-3H-benzo[f]chromen-2-yl)methanone, phenyl(3-oxo-3H-benzo[f]chromen-2-yl)methanone, and (4-chlorophenyl)(3-oxo-3H-benzo[f]chromen-2-yl)methanone are promising as antimicrobial drugs.  相似文献   
995.
The association of TP53 codon 72 polymorphism with cancer susceptibility remains uncertain and varies with ethnicity. Northeast India represents a geographically, culturally, and ethnically isolated population. The area reports high rate of tobacco usage in a variety of ways of consumption, compared with the rest of Indian population. A total of 411 cancer patients (161 lung, 134 gastric, and 116 oral) and 282 normal controls from the ethnic population were analyzed for p53 codon 72 polymorphism by polymerase chain reaction-restriction fragment length polymorphism. No significant difference in genotypic distribution of p53 between cases and controls was observed. Results suggested betel quid chewing as a major risk factor for all the three cancers (odds ratio [OR]=3.54, confidence interval [CI]=2.01-6.25, p<0.001; OR=1.74, CI=1.04-2.92, p=0.03; and OR=1.85, CI=1.02-3.33, p=0.04 for lung, gastric, and oral cancers, respectively). Tobacco smoking was associated with risk of lung and oral cancers (OR=1.88, CI=1.11-3.19, p=0.01 and OR=1.68, CI=1.00-2.81, p=0.04). Interactions between p53 genotypes and risk factors were analyzed to look for gene-environment interactions. Interaction of smoking and p53 genotype was significant only for oral cancer. Interactions of betel quid with p53 genotypes in lung cancer showed significant increase for all the three genotypes, indicating a major role of betel quid (OR=5.90, CI=1.67-20.81, p=0.006; OR=5.44, CI=1.67-17.75, p=0.005; and OR=5.84, CI=1.70-19.97, p=0.005 for Arg/Arg, Arg/Pro, and Pro/Pro, respectively). In conclusion, high incidence of these cancers in northeast India might be an outcome of risk habits; further, tissue- and carcinogen-specific risk modification by p53 gene is probable.  相似文献   
996.
Epithelial mesenchymal transition (EMT) and cancer stem cells (CSC) have been associated with resistance to chemotherapy. Eighty percent of ovarian cancer patients initially respond to platinum-based combination therapy but most return with recurrence and ultimate demise. To better understand such chemoresistance we have assessed the potential role of EMT in tumor cells collected from advanced-stage ovarian cancer patients and the ovarian cancer cell line OVCA 433 in response to cisplatin in vitro. We demonstrate that cisplatin-induced transition from epithelial to mesenchymal morphology in residual cancer cells correlated with reduced E-cadherin, and increased N-cadherin and vimentin expression. The mRNA expression of Snail, Slug, Twist, and MMP-2 were significantly enhanced in response to cisplatin and correlated with increased migration. This coincided with increased cell surface expression of CSC-like markers such as CD44, α2 integrin subunit, CD117, CD133, EpCAM, and the expression of stem cell factors Nanog and Oct-4. EMT and CSC-like changes in response to cisplatin correlated with enhanced activation of extracellular signal-regulated kinase (ERK)1/2. The selective MEK inhibitor U0126 inhibited ERK2 activation and partially suppressed cisplatin-induced EMT and CSC markers. In vivo xenotransplantation of cisplatin-treated OVCA 433 cells in zebrafish embryos demonstrated significantly enhanced migration of cells compared to control untreated cells. U0126 inhibited cisplatin-induced migration of cells in vivo, suggesting that ERK2 signaling is critical to cisplatin-induced EMT and CSC phenotypes, and that targeting ERK2 in the presence of cisplatin may reduce the burden of residual tumor, the ultimate cause of recurrence in ovarian cancer patients.  相似文献   
997.
A tropical marine bacterium isolated from the hard coral, Symphyllia sp. was identified as Serratia marcescens on the basis of morphological, biochemical and 16S rDNA analysis. The bacterium showed antimicrobial activity towards the pathogens Candida albicans and Pseudomonas aeruginosa and the marine biofouling bacterium Bacillus pumilus. S. marcescens displayed biosurfactant activity as evidenced by drop collapse, blood hemolysis and surface tension reduction (52.0-27 mN m(-1)). The active compound was purified by solvent extraction and silicic acid chromatography. Characterization was by thin layer chromatography, gas chromatography mass spectroscopy (GC-MS), Fourier transform infrared (FTIR) spectroscopy and (1)H as well as (13)C nuclear magnetic resonance (NMR) analysis. The surfactant was found to be a glycolipid composed of glucose and palmitic acid. The glycolipid prevented adhesion of C. albicans BH, P. aeruginosa PAO1 and B. pumilus TiO1. The glycolipid also disrupted preformed biofilms of these cultures in microtitre plates. Confocal laser scanning microscopy and electron microscopy confirmed the effective removal of biofilms from glass surfaces. The glycolipid derived from S. marcescens could thus serve as a potential anti-biofilm agent.  相似文献   
998.
The entry of dengue viruses is mediated by pH triggering in the host cells. Here we have studied the DENV E protein stability and binding of its units at low and normal pH using MD and MM-PB/SA method for the first time. To investigate the role of pH in dissociation of dimeric protein, we have performed a concise study of hydrogen bonding and other interactions between units of dimer at low and normal pH. The Generalized Born calculation connotes that dimeric unit was relatively less stable and less proned for dimerisation at low pH. Our results provide a theoretical verification for previous assumptions of pH triggering mechanism of dengue envelope protein. During the pH alteration, we found a large decrement in salt bridges which were observed at normal pH. We also compared the flexibility of each unit and found that they exhibit different fluctuations during molecular dynamics simulations.  相似文献   
999.
Recent reports highlight the severity and the morbidity of disease caused by the long neglected malaria parasite Plasmodium vivax. Due to inherent difficulties in the laboratory-propagation of P. vivax, the biology of this parasite has not been adequately explored. While the proteome of P. falciparum, the causative agent of cerebral malaria, has been extensively explored from several sources, there is limited information on the proteome of P. vivax. We have, for the first time, examined the proteome of P. vivax isolated directly from patients without adaptation to laboratory conditions. We have identified 153 proteins from clinical P. vivax, majority of which do not show homology to any previously known gene products. We also report 29 new proteins that were found to be expressed in P. vivax for the first time. In addition, several proteins previously implicated as anti-malarial targets, were also found in our analysis. Most importantly, we found several unique proteins expressed by P. vivax.This study is an important step in providing insight into physiology of the parasite under clinical settings.  相似文献   
1000.
Hepcidin is an anti-microbial peptide expressed predominantly in the liver of many species. Based on the amino acid sequence deduced from buffalo (Bubalus bubalis) hepcidin cDNA (Accession no. EU399814), six peptides Hepc(1-25), Hepc(6-25), Hepc(7-25), Hepc(9-25), Hepc(11-25) and Hepc(15-25) were synthesized using solid-phase fluorenylmethoxycarbonyl (Fmoc) chemistry. CD spectroscopy revealed different spectra of the peptides in different solvents and in all the cases beta-structure was found to be dominant with less alpha-helix as predicted. Quantitation of secondary structure indicated the highest beta-structure for all the six peptides in SDS solution, when used as mimetic for membrane-like environment. The CD spectra of all the peptides taken in water showed that degree of randomness decreased with increase in chain length of the peptide. Out of the six peptides, only Hepc(1-25), Hepc(6-25) and Hepc(7-25) showed antibacterial activity against Staphylococcus aureus (Gram-positive bacteria). The peptides did not show any sensitivity toward E. coli (Gram-negative bacteria). Minimum inhibitory concentration (MIC) showed the lowest value for Hepc(7-25) as an antibacterial agent, followed by Hepc(6-25) and Hepc(1-25). The peptides Hepc(9-25), Hepc(11-25) and Hepc(15-25) with more random structure did not show any antimicrobial activity The study demonstrated that 5 amino acids at N-terminal in buffalo hepcidin can be truncated without loss of antimicrobial activity and further reduction of length of the analog from 20 to 19 amino acids resulted increase in the activity because of increase in beta-structure of the peptide shown by CD spectroscopy.  相似文献   
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