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791.
Persons with their eye closed and without any means of communication is said to be in a completely locked-in state (CLIS) while when they could still open their eyes actively or passively and have some means of communication are said to be in locked-in state (LIS). Two patients in CLIS without any means of communication, and one patient in the transition from LIS to CLIS with means of communication, who have Amyotrophic Lateral Sclerosis were followed at a regular interval for more than 1 year. During each visit, resting-state EEG was recorded before the brain–computer interface (BCI) based communication sessions. The resting-state EEG of the patients was analyzed to elucidate the evolution of their EEG spectrum over time with the disease’s progression to provide future BCI-research with the relevant information to classify changes in EEG evolution. Comparison of power spectral density (PSD) of these patients revealed a significant difference in the PSD’s of patients in CLIS without any means of communication and the patient in the transition from LIS to CLIS with means of communication. The EEG of patients without any means of communication is devoid of alpha, beta, and higher frequencies than the patient in transition who still had means of communication. The results show that the change in the EEG frequency spectrum may serve as an indicator of the communication ability of such patients.Electronic supplementary materialThe online version of this article (10.1007/s11571-020-09639-w) contains supplementary material, which is available to authorized users.  相似文献   
792.
793.
Under field conditions, plants are often simultaneously exposed to several abiotic and biotic stresses resulting in significant reductions in growth and yield; thus, developing a multi-stress tolerant variety is imperative. Previously, we reported the neofunctionalization of a novel PNP family protein, Putranjiva roxburghii purine nucleoside phosphorylase (PRpnp) to trypsin inhibitor to cater to the needs of plant defence. However, to date, no study has revealed the potential role and mechanism of either member of this protein group in plant defence. Here, we overexpressed PRpnp in Citrus aurantifolia which showed nuclear-cytoplasmic localization, where it functions in maintaining the intracellular purine reservoir. Overexpression of PRpnp significantly enhanced tolerance to salt, oxidative stress, alkaline pH, drought and two pests, Papilio demoleus and Scirtothrips citri in transgenic plants. Global gene expression studies revealed that PRpnp overexpression up-regulated differentially expressed genes (DEGs) related to ABA- and JA-biosynthesis and signalling, plant defence, growth and development. LC–MS/MS analysis validated higher endogenous ABA and JA accumulation in transgenic plants. Taken together, our results suggest that PRpnp functions by enhancing the endogenous ABA and JA, which interact synergistically and it also inhibits trypsin proteases in the insect gut. Also, like other purine salvage genes, PRpnp also regulates CK metabolism and increases the levels of CK-free bases in transgenic Mexican lime. We also suggest that PRpnp can be used as a potential candidate to develop new varieties with improved plant vigour and enhanced multiple stress resistance.  相似文献   
794.
E. Perry  R. K. Chaudhary 《CMAJ》1973,109(9):857-859
Hepatitis B antigen (HBAg) from blood donors and patients with hepatitis was tested for ad and ay subspecificity by immunodiffusion in agarose. A total of 59 sera from blood donors and 81 sera from hepatitis patients were subtyped.Subtyping of HBAg from blood donors showed ad and ay subspecificity in 64.4 and 35.6% of cases respectively. Patients'' sera on the other hand showed HBAg with ad and ay subspecificity in 6 and 94% of cases respectively. Therefore, ad subtype was more frequently associated with blood donors whereas ay subtype was predominant among hepatitis patients. The relationship between clinical findings and HBAg subtype is also discussed.  相似文献   
795.
In the present investigation, we employ a dual approach consisting of experimental and computational techniques to synthesise and characterise the Schiff-base including the moieties of nitrophenyl (3), nitrothiazole (5) and nitrobenzothiazole (7). The synthesised Schiff bases are confirmed by FT-IR, 1H-NMR and UV-visible spectroscopic techniques. The experimental UV-visible spectroscopic results are compared to the theoretically calculated TD-DFT results. There is a reasonably good agreement between the experimental and the theoretically calculated spectroscopic results. We also calculate the third-order nonlinear optical (NLO) polarizability (γ) of above entitled derivatives using finite field (FF) approach and DFT methods. The compound 7 shows an amplitude of γ as large as 124.15×104 a. u., which is found to be several times larger than that of para-nitroaniline. Moreover, the partial and total density of states (PDOS and TDOS) along with electrostatic potential maps are calculated to get more physical insights into the structure-property relationship and electronic communications between terminal donor and central core acceptor moieties in the synthesised compounds. The present investigation highlights the significance of indigenously synthesised nitrothiazole and nitrobenzothiazole compounds as efficient NLO materials, which may evoke the interest of scientific community in such efficient NLO materials for their potential utilization in device applications.  相似文献   
796.
Increased antibacterial resistance (ABR) and limited drug discovery warrant optimized use of available antibiotics. One option is to rationally combine two antibiotics (fixed dose combination (FDC)) that may delay or prevent emergence of ABR in notorious pathogen. Major concern with FDC is the mutual interaction of its components that might influence their pharmacokinetic (PK) profile, requiring reassessing of whole formulation (adding cost and time). The interaction can be identified by comparing PK profile of a drug present in FDC with its independent entity. An open-label, crossover, single-dose comparative PK study of FDC (ceftriaxone and sulbactam) with their individual reference formulations was performed in 24 healthy adult subjects. No mutual PK interactions between ceftriaxone and sulbactam were observed. Pharmacokinetic data was used to develop a population-PK model to understand between-subject variability (BSV). Pharmacokinetics of ceftriaxone/sulbactam was explained by one and two compartment models, respectively. The subject’s “weight” was identified as a covariate explaining BSV. Both internal and external validations (healthy/infected subjects) were done. The model-derived population-PK parameters of FDC’s active components in infected subjects were similar to literature reported values of individual components. Efficacies of various FDC dosage regimens over a range of minimum inhibitory concentrations (MICs) were assessed by Monte Carlo simulations using population-PK parameters of infected/healthy subjects. In infected subjects, 3 g FDC/24 h can treat bacteria with MIC ≤8 μg/mL, while for MIC 8–32 μg/mL, 3 g FDC/12 h is recommended. Lastly, the developed population-PK model was successfully used to predict drug exposure in pediatric population.  相似文献   
797.
Skewing of the sex ratio towards males occurs in humans. The possible explanation for excess male births could be a preference for Y-bearing sperm at fertilization and/or selective elimination of female embryos during pregnancy. In this study, we have tested the sex ratio in the preimplantation embryo (2–3 cells stage/closest possible primary sex ratio), the post-implantation embryo (day E7.5), and at birth (secondary sex ratio) on a homogenous (genetic, environmental, and dietary) population of mice to ascertain the biological reason i.e., male preference at fertilization or female elimination during pregnancy or both. Primary sex ratio on early preimplantation embryos (2–3 cells stage) was studied on 598 embryos and secondary sex ratio (at birth) on 721 pups using PCR-based sexing (both X & Y chromosome-specific) besides sex ratio of 80 post-implantation embryos (day E7.5). We have also investigated whether the fat content (high & low) of the diet affects the sex ratio. We observed a skewed sex ratio (more female) in preimplantation embryos (0.436; 95 % CI 0.39, 0.48), and post-implantation embryos (0.462; 95 % CI 0.35, 0.57) but reverse skewing (more male) at birth (0.539; 95 % CI 0.5, 0.58). We also observed that high-fat diet promoted male sex ratio at birth (0.657; 95 % CI 0.57, 0.74) whereas a low-fat diet had the opposite effect (0.46; 95 % CI 0.36, 0.56) but no effect at fertilization (2–3 cells stage embryos). This indicates selective elimination of female embryo and fetus throughout pregnancy in mice, more so with a high-fat diet.  相似文献   
798.
Five salinity tolerant Azotobacter strains i.e., ST3, ST6, ST9, ST17 and ST24 were obtained from saline soils. These Azotobacter strains were used as inoculant for wheat variety WH157 in earthen pots containing saline soil under pot house conditions, using three fertilizer treatment doses i.e., control (no fertilizer, no inoculation), 90 Kg N ha−1 and 120 Kg N ha−1. Inoculation with salinity tolerant Azotobacter strains caused significant increase in total nitrogen, biomass and grain yield of wheat. Maximum increase in plant growth parameters were obtained after inoculation with Azotobacter strain ST24 at fertilization dose of 120 kg N ha−1 and its inoculation resulted in attaining 89.9 cms plant height, 6.1 g seed yield, 12.0 g shoot dry weight and 0.7 % total nitrogen. The survival of Azotobacter strain ST24 in the soil was also highest in all the treatments at 30, 60 and 90 days after sowing (DAS). However, the population of Azotobacter decreased on 90 DAS as compared to counts observed at 60 DAS at all the fertilization treatments.  相似文献   
799.
800.
The prevalence of hepatitis B surface antigen (HBsAg) in 14 347 Indochinese refugees was 11.6%; the rate was significantly higher (P less than 0.01) in males (14.0%) than in females (8.8%). Most of the HBsAg-positive refugees were in the age group 20 to 29 years. Antibody to HBsAg was detected in 50.9% of the males and 46.6% of the females, a significant difference (P less than 0.01). Antibody to core antigen alone was found in 2.4% of the males and 2.2% of the females. The cumulative prevalence of one or more hepatitis B markers was significantly higher (P less than 0.001) in the males (67.3%) than in the females (57.5%). The hepatitis B e antigen and its antibody were detected in 54.8% and 39.2% respectively of 1050 HBsAg-positive blood samples. The adw, adr and ayw determinants of HBsAg were found in 23%, 35% and 42% respectively of 74 samples.  相似文献   
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