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251.
252.
Tony M. Johnson A. S. Rishi Pritilata Nayak Soumitra K. Sen 《Journal of biosciences》1996,21(5):673-685
Damage caused to rice production by coleopteran insects like rice weevil (Sitophilus oryzae), a stored grain insect pest and rice hispa (Dicladispa armigera), a pest of the growing plant is quite high. In order to combat the damage, generation of insect resistant transgenic rice
plant was considered desirable. CryIIIA endotoxin ofBacillus thuringiensis var.tenebrionis, a 65 kDa protein toxic to coleopteran insects, figured as the candidate gene product. Thus, the cryIIIA gene was isolated
from a local isolate ofBacillus thuringiensis var.tenebrionis. The gene was tailored at the N-terminal end to its minimal size by using a synthetic ATG codon which replaced the first
codon next to ATG of threonine to proline. This modification did not affect the functional property of the gene product. A
chimeric construct of the modifiedcryIIIA gene was developed containing CaMV35S promoter andnos terminator for plant expression. The expressibility of thecryIIIA gene inindica rice was judged through test for transient expression in indica rice protoplasts. 相似文献
253.
In the present study, mineralization of an aromaticN-heterocyclic molecule, indole, by microorganisms present in anaerobically digested sewage sludge was examined. The first
step in indole mineralization was the formation of a hydroxylated intermediate, oxindole. The rate of transformation of indole
to oxindole and its subsequent disappearance was dependent on the concentration of inoculum and indole and the incubation
temperature. Methanogenesis appeared to be the dominant process in the mineralization of indole in 10% digested sludge even
in the presence of high concentrations of sulfate. Enrichment of the digested sludge with sulfate as an electron acceptor
allowed the isolation of a metabolically stable mixed culture of anaerobic bacteria which transformed indole to oxindole and
acetate, and ultimately to methane and carbon dioxide. This mixed culture exhibited a predominance of sulfate-reducers over
methanogens with more than 75% of the substrate mineralized to carbon dioxide. The investigation demonstrates that indole
can be transformed by both methanogenic and sulfate-reducing microbial populations. 相似文献
254.
Rishi Maiti Tridib K. Sinha Subhrajit Mukherjee Basudam Adhikari Samit K. Ray 《Plasmonics (Norwell, Mass.)》2016,11(5):1297-1304
We report the fabrication and characteristics of a novel graphene-Ag0 hybrid plasmonic nanostructure-based photodetector exhibiting moderately high responsivity (~28 mA/W) and spectral selectivity (~510 nm) in the visible wavelength. The formation of highly stable Ag0 nanoparticles with an average size of 40 nm is observed within the graphene layers, resulting in n-type doping of hybrid material. The absorption peak of graphene-Ag0 hybrid is redshifted to the visible wavelength (~510 nm) from the plasmonic Ag peak (~380 nm) in agreement with the optical simulation results for embedded metal nanoparticles. The study demonstrates the synergistic effect of the graphene-metal nanocomposite, which appears attractive for applications in graphene-based photonic devices. 相似文献
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257.
Ulphani JS Arora R Cain JH Villuendas R Shen S Gordon D Inderyas F Harvey LA Morris A Goldberger JJ Kadish AH 《American journal of physiology. Heart and circulatory physiology》2007,293(3):H1629-H1635
The objective of the study was to investigate the morphology, distribution, and electrophysiological profile of the autonomic fibers that innervate the ligament of Marshall (LOM). Gross anatomical dissections were performed in 10 dogs. Sections of the left vagus nerve, left stellate ganglion, and the LOM were immunostained to identify adrenergic and cholinergic nerves. Hearts were also stained for acetylcholinesterase to identify epicardial cholinergic nerves. In vivo electrophysiological studies were performed in another 10 dogs before and after LOM ablation. The anatomical examination revealed that the LOM is innervated by a branch of the left vagus. Immunohistochemistry confirmed that these nerve bundles are predominantly cholinergic (cholinergic-to-adrenergic ratio of 12.6 +/- 3.9:1). Cholinergic nerves originating in the LOM were found to innervate surrounding left atrial structures, including the pulmonary veins, left atrial appendage, coronary sinus, and posterior left atrial fat pad. Ablation of the LOM significantly attenuated effective refractory period shortening at distant sites, such as pulmonary veins and left atrial appendage, in response to vagal stimulation (vagal-induced ERP decrease in the left atrium: baseline vs. postablation = 17 vs. 4%; P = 0.0056). In conclusion, the LOM contains a predominance of cholinergic nerve fibers. Cholinergic fibers arising from the LOM innervate surrounding structures and contribute to the electrophysiological profile of the left atrium. These findings may provide a basis for the role of the LOM in the genesis and maintenance of atrial fibrillation. 相似文献
258.
Garanich JS Mathura RA Shi ZD Tarbell JM 《American journal of physiology. Heart and circulatory physiology》2007,292(6):H3128-H3135
The involvement of vascular fibroblasts (FBs) and smooth muscle (SM)-like cells in physiological and pathological processes in large vessels (intimal hyperplasia) and microvessels (capillary arterialization), and the realization that these cells are exposed to interstitial flow shear stress (SS), motivate this study of SS on FB migratory activity. Rat adventitial FBs were grown to either 30-50% confluence (subconfluent FBs; SFBs) or full confluence (confluent FBs; CFBs) in culture. Immunofluorescence and Western blotting assays were conducted to evaluate the expression of two phenotype markers: SM alpha-actin and SM myosin heavy chain (MHC). Both assays indicated a significant increase in SM alpha-actin expression in CFBs compared with SFBs, suggesting a phenotype difference between the two cell populations. SFBs and CFBs both expressed minimal SM MHC. Both cell populations were seeded on Matrigel-coated cell culture inserts and exposed to 4 h of either 1 or 20 dyn/cm(2) SS via a rotating disk apparatus in the presence of the chemoattractant platelet-derived growth factor-BB to quantify the effect of SS on SFB and CFB migration. Four hours of 20 dyn/cm(2) SS significantly enhanced SFB migration while it suppressed CFB migratory activity. Four hours of 1 dyn/cm(2) SS did not significantly alter either SFB or CFB migration levels. Because of the distinct migratory responses of SFBs and CFBs in response to SS, phenotype modulation appears to be one way to regulate their involvement in both physiological and pathological remodeling processes. 相似文献
259.
Sekhon Prabhjot Kaur Chander Atul Munish Mayilraj Shanmugam Rishi Praveen 《Molecular biology reports》2019,46(4):3967-3989
Molecular Biology Reports - In the era of emerging antibiotic resistance, Salmonella enterica subsp. enterica serovar Typhi the causative agent of typhoid, is a threat for healthcare systems in... 相似文献
260.
Increased localization of APP‐C99 in mitochondria‐associated ER membranes causes mitochondrial dysfunction in Alzheimer disease
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Marta Pera Delfina Larrea Cristina Guardia‐Laguarta Jorge Montesinos Kevin R Velasco Rishi R Agrawal Yimeng Xu Robin B Chan Gilbert Di Paolo Mark F Mehler Geoffrey S Perumal Frank P Macaluso Zachary Z Freyberg Rebeca Acin‐Perez Jose Antonio Enriquez Eric A Schon Estela Area‐Gomez 《The EMBO journal》2017,36(22):3356-3371
In the amyloidogenic pathway associated with Alzheimer disease (AD), the amyloid precursor protein (APP) is cleaved by β‐secretase to generate a 99‐aa C‐terminal fragment (C99) that is then cleaved by γ‐secretase to generate the β‐amyloid (Aβ) found in senile plaques. In previous reports, we and others have shown that γ‐secretase activity is enriched in mitochondria‐associated endoplasmic reticulum (ER) membranes (MAM) and that ER–mitochondrial connectivity and MAM function are upregulated in AD. We now show that C99, in addition to its localization in endosomes, can also be found in MAM, where it is normally processed rapidly by γ‐secretase. In cell models of AD, however, the concentration of unprocessed C99 increases in MAM regions, resulting in elevated sphingolipid turnover and an altered lipid composition of both MAM and mitochondrial membranes. In turn, this change in mitochondrial membrane composition interferes with the proper assembly and activity of mitochondrial respiratory supercomplexes, thereby likely contributing to the bioenergetic defects characteristic of AD. 相似文献