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891.
892.
The water quality of the Siluko River, Edo State, Nigeria was investigated from March to August 2015 to determine its suitability for drinking and usage for domestic purposes. Water samples collected from three stations were tested for thirteen physico-chemical parameters using standard analytical procedures. Temperature, phosphate and chloride were significantly different across the three stations. All other parameters, with the exception of turbidity, dissolved oxygen and phosphate, were within the permissible limits recommended by the Nigerian Standard for Drinking Water Quality (NSDWQ) and World Health Organization (WHO). Water Quality Index (WQI) values ranged from 11.24 to 16.15, indicating excellent water quality. While the quality of the water from the Siluko River is suitable for drinking and domestic usage, to prevent future deterioration of the water, it is recommended that the regulating authorities monitor effluents discharged into the river from human activities. 相似文献
893.
Jae Young Choi Yang-Su Kim Yong Wang Joong Nam Kang Jong Yul Roh Hee Jin Shim Soo-Dong Woo Byung Rae Jin Yeon Ho Je 《Molecules and cells》2009,28(1):19-24
The goal of this study was to create a novel baculovirus expression system that does not require recombinant virus purification steps. Transfection of insect cells with transfer vectors containing barnase under control of the Cotesia plutellae bracovirus (CpBV) promoters ORF3004 or ORF3005 reduced cell growth. Co-transfection with bApGOZA DNA yielded no recombinant viruses and non-recombinant backgrounds. To further investigate the detrimental effects of barnase on insect cells, two recombinant bacmids harboring the barnase gene under control of the CpBV promoters, namely bAcFast-3004ProBarnase and bAcFast-3005ProBarnase, were constructed. While no viral replication was observed when only the recombinant bacmids were transfected, recombinant viruses were generated when the bacmids were co-transfected with the transfer vector, pAcUWPolh, through substitution of the barnase gene with the native polyhedrin gene by homologous recombination. Moreover, no non-recombinant backgrounds were detected from unpurified recombinant stocks using PCR analysis. These results indicate that CpBV promoters can be used to improve baculovirus expression vectors by means of lethal gene expression under the control of these promoters. 相似文献
894.
Na Rae Han Song Baek Hwa-Young Kim Kwon Young Lee Jung Im Yun Jung Hoon Choi 《Animal cells and systems.》2020,24(2):91-98
ABSTRACT Embryonic stem cells (ESCs) derived from outbred mice which share several genetic characteristics similar to humans have been requested for developing stem cell-based bioengineering techniques directly applicable to humans. Here, we report the generation of ESCs derived from the inner cell mass of blastocysts retrieved from 9-week-old female outbred ICR mice mated with 9-week-old male outbred ICR mice (ICRESCs). Similar to those from 129/Ola mouse blastocysts (E14ESCs), the established ICRESCs showed inherent characteristics of ESCs except for partial and weak protein expression and activity of alkaline phosphatase. Moreover, ICRESCs were not originated from embryonic germ cells or pluripotent cells that may co-exist in outbred ICR strain-derived mouse embryonic fibroblasts (ICRMEFs) used for deriving colonies from inner cell mass of outbred ICR mouse blastocysts. Furthermore, instead of outbred ICRMEFs, hybrid B6CBAF1MEFs as feeder cells could sufficiently support in vitro maintenance of ICRESC self-renewal. Additionally, ICRESC-specific characteristics (self-renewal, pluripotency, and chromosomal normality) were observed in ICRESCs cultured for 40th subpassages (164 days) on B6CBAF1MEFs without any alterations. These results confirmed the successful establishment of ESCs derived from outbred ICR mice, and indicated that self-renewal and pluripotency of the established ICRESCs could be maintained on B6CBAF1MEFs in culture. 相似文献
895.
The growth of six strains of Pseudomonas fluorescens , two of Ps. fragi , and one of Serratia liquefaciens was followed in raw and UHT-treated goats'milk, held at 4°C. Generation times for Ps. fluorescens in UHT milk ranged from 5.19 to 5.81 h, increasing markedly in raw milk (8.34–21.49 h). Growth of Ps. fragi did not differ significantly between raw (4.56, 4.65 h) and UHT (5.04, 7.24 h) milk. Generation times for S. liquefaciens were 6.63 and 14.07 h, for UHT and raw milk respectively. 相似文献
896.
897.
A novel inhibitor of lactate transport, AR-C122982, was used to study the effect of inhibiting the monocarboxylate transporters
MCT1 and MCT2 on cortical brain slice metabolism. We studied metabolism of l-[3-13C]lactate, and d-[1-13C]glucose under a range of conditions. Experiments using l-[3-13C]lactate showed that the inhibitor AR-C122982 altered exchange of lactate. Under depolarizing conditions, net flux of label
from d-[1-13C]glucose was barely altered by 10 or 100 nM AR-C122982. In the presence of AMPA or glutamate there were increases in net
flux of label and metabolic pool sizes. These data suggest lactate may supply compartments in the brain not usually directly
accessed by glucose. In general, it would appear that movement of lactate between cell types is not essential for metabolic
activity, with the heavy metabolic workloads imposed being unaffected by inhibition of MCT1 and MCT2. Further experiments
investigating the mechanism of operation of AR-C122982 are necessary to corroborate this finding. 相似文献
898.
899.
Hyun Na Koo Jeong Mi Oh Jae Kyung Lee Jae Young Choi Kwang Sik Lee Jong Yul Roh Yeon Ho Je Byung Rae Jin Sung Sik Yoo Jae Su Kim Young In Kim In Joong Yoon Soo Dong Woo 《Journal of microbiology (Seoul, Korea)》2008,46(6):709-719
To determine the characteristics of the Korean porcine reproductive and respiratory syndrome virus (PRRSV), CA, which was
isolated from the serum of an infected pig in 2006, we investigated the nucleotide sequence and expression of the structural
ORFs (ORFs 2 to 7) using the bApGOZA system. We found that the structural ORFs 2 to 7 of CA consisted of 3188 nucleotides
that were the same as those formed from VR-2332. Comparison of the CA with the other strains revealed nucleotide sequence
identity ranging from 89.8 to 99.5%. To better understand the genetic relationships between other strains, phylogenetic analyses
were performed. The CA strain was closely related to the other North American genotype strains but formed a distinct branch
with high bootstrap support. Additionally, expression levels of the PRRSV proteins in insect cells were strong or partially
weak. The results of this study have implications for both the taxonomy of PRRSV and vaccine development. 相似文献
900.