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142.
Gustavo Ciudad Isaac Reyes Milko A. Jorquera Laura Azócar Lukas Y. Wick Rodrigo Navia 《World journal of microbiology & biotechnology》2011,27(11):2505-2512
A novel three-phase solid–gas–liquid bioreactor (SGLB) concept using gaseous alcohol and liquid rapeseed oil with immersed
microorganisms overlying a nutrient agar phase (solid) is proposed for biodiesel (fatty acid alkyl esters, FAAE) production
based on the high hydrophobicity and negative surface charge showed by the fungi Rhizopus oryzae. This novel bioreactor was thought to increase oil bioavailability and decrease alcohol toxicity for effective microbial
growth, reaching high yields of FAAE production without any pretreatment. High growth rates were reached for R. oryzae using a SGLB simultaneously reaching a high FAAE production yield, up to 50% using methanol and up to 70% using ethanol at
144 h of incubation at 20°C. To compare the effect of gaseous alcohol, the same experiments were carried out in a three-phase
solid–liquid–liquid bioreactor (SLLB), where the alcohol was added in liquid phase, showing significant R. oryzae growth but no FAAE formation. This suggests that the inhibitory effect of alcohol is more significant in lipase activity
than in R. oryzae growth, and the use of alcohol in gaseous phase may decrease both of them. The experimental procedure using SGLB showed that
when R. oryzae is maintained alive, it can catalyze at the same time the hydrolysis, esterification and transesterification of triglycerides
from rapeseed oil, but its activity strongly depends on the used growth media. Therefore, the application of gaseous alcohol
coupled with R. oryzae as immobilized whole cell catalysts may be a potential alternative to the use of commercial lipases for biodiesel production. 相似文献
143.
In cerebral cortex there is a developmental switch from NR2B- to NR2A-containing NMDA receptors (NMDARs) driven by activity and sensory experience. This subunit switch alters NMDAR function, influences synaptic plasticity, and its dysregulation is associated with neurological disorders. However, the mechanisms driving the subunit switch are not known. Here, we show in hippocampal CA1 pyramidal neurons that the NR2B to NR2A switch driven acutely by activity requires activation of NMDARs and mGluR5, involves PLC, Ca(2+) release from IP(3)R-dependent stores, and PKC activity. In mGluR5 knockout mice the developmental NR2B-NR2A switch in CA1 is deficient. Moreover, in visual cortex of mGluR5 knockout mice, the NR2B-NR2A switch evoked in?vivo by visual experience is absent. Thus, we establish that mGluR5 and NMDARs are required for the activity-dependent NR2B-NR2A switch and play a critical role in experience-dependent regulation of NMDAR subunit composition in?vivo. 相似文献
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Mwandi Z Murphy A Reed J Chesang K Njeuhmeli E Agot K Llewellyn E Kirui C Serrem K Abuya I Loolpapit M Mbayaki R Kiriro N Cherutich P Muraguri N Motoku J Kioko J Knight N Bock N 《PLoS medicine》2011,8(11):e1001130
Since the World Health Organization and the Joint United Nations Programme on HIV/AIDS recommended implementation of medical male circumcision (MC) as part of HIV prevention in areas with low MC and high HIV prevalence rates in 2007, the government of Kenya has developed a strategy to circumcise 80% of uncircumcised men within five years. To facilitate the quick translation of research to practice, a national MC task force was formed in 2007, a medical MC policy was implemented in early 2008, and Nyanza Province, the region with the highest HIV burden and low rates of circumcision, was prioritized for services under the direction of a provincial voluntary medical male circumcision (VMMC) task force. The government's early and continuous engagement with community leaders/elders, politicians, youth, and women's groups has led to the rapid endorsement and acceptance of VMMC. In addition, several innovative approaches have helped to optimize VMMC scale-up. Since October 2008, the Kenyan VMMC program has circumcised approximately 290,000 men, mainly in Nyanza Province, an accomplishment made possible through a combination of governmental leadership, a documented implementation strategy, and the adoption of appropriate and innovative approaches. Kenya's success provides a model for others planning VMMC scale-up programs. 相似文献
146.
Shafat I Ben-Arush MW Issakov J Meller I Naroditsky I Tortoreto M Cassinelli G Lanzi C Pisano C Ilan N Vlodavsky I Zunino F 《Journal of cellular and molecular medicine》2011,15(9):1857-1864
Heparanase is an endoglycosidase that specifically cleaves heparan sulphate side chains of heparan sulphate proteoglycans, activity that is strongly implicated in cell migration and invasion associated with tumour metastasis, angiogenesis and inflammation. Heparanase up-regulation was documented in an increasing number of human carcinomas, correlating with reduced post-operative survival rate and enhanced tumour angiogenesis. Expression and significance of heparanase in human sarcomas has not been so far reported. Here, we applied the Ewing's sarcoma cell line TC71 and demonstrated a potent inhibition of cell invasion in vitro and tumour xenograft growth in vivo upon treatment with a specific inhibitor of heparanase enzymatic activity (compound SST0001, non-anticoagulant N-acetylated, glycol split heparin). Next, we examined heparanase expression and cellular localization by immunostaining of a cohort of 69 patients diagnosed with Ewing's sarcoma. Heparanase staining was noted in all patients. Notably, heparanase staining intensity correlated with increased tumour size (P = 0.04) and with patients' age (P = 0.03), two prognostic factors associated with a worse outcome. Our study indicates that heparanase expression is induced in Ewing's sarcoma and associates with poor prognosis. Moreover, it encourages the inclusion of heparanase inhibitors (i.e. SST0001) in newly developed therapeutic modalities directed against Ewing's sarcoma and likely other malignancies. 相似文献
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Miyamoto DM Ruff K Beach NM Stockwell SB Dorsey-Oresto A Masters I Temple LM 《Microbes and infection / Institut Pasteur》2011,13(10):871-879
Bordetellosis is an upper respiratory disease of turkeys caused by Bordetella avium in which the bacteria attach specifically to ciliated respiratory epithelial cells. Little is known about the mechanisms of pathogenesis of this disease, which has a negative impact in the commercial turkey industry. In this study, we produced a novel explant organ culture system that was able to successfully reproduce pathogenesis of B. avium in vitro, using tracheal tissue derived from 26 day-old turkey embryos. Treatment of the explants with whole cells of B. avium virulent strain 197N and culture supernatant, but not lipopolysaccharide (LPS) or tracheal cytotoxin (TCT), specifically induced apoptosis in ciliated cells, as shown by annexin V and TUNEL staining. LPS and TCT are known virulence factors of Bordetella pertussis, the causative agent of whooping cough. Treatment with whole cells of B. avium and LPS specifically induced NO response in ciliated cells, shown by uNOS staining and diaphorase activity. The explant system is being used as a model to elucidate specific molecules responsible for the symptoms of bordetellosis. 相似文献
150.
Kohane IS 《Nature reviews. Genetics》2011,12(6):417-428
If genomic studies are to be a clinically relevant and timely reflection of the relationship between genetics and health status--whether for common or rare variants--cost-effective ways must be found to measure both the genetic variation and the phenotypic characteristics of large populations, including the comprehensive and up-to-date record of their medical treatment. The adoption of electronic health records, used by clinicians to document clinical care, is becoming widespread and recent studies demonstrate that they can be effectively employed for genetic studies using the informational and biological 'by-products' of health-care delivery while maintaining patient privacy. 相似文献