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991.
Rahmad Akbar Philippe A. Robert Cdric R. Weber Michael Widrich Robert Frank Milena Pavlovi Lonneke Scheffer Maria Chernigovskaya Igor Snapkov Andrei Slabodkin Brij Bhushan Mehta Enkelejda Miho Fridtjof Lund-Johansen Jan Terje Andersen Sepp Hochreiter Ingrid Hobk Haff Günter Klambauer Geir Kjetil Sandve Victor Greiff 《MABS-AUSTIN》2022,14(1)
992.
993.
Katsuhiro Kojima Akane Mikami-Sakaguchi Miho Kameya Yusuke Miyamoto Stefano Ferri Wakako Tsugawa Koji Sode 《Biotechnology letters》2013,35(2):253-258
A three-dimensional structural model of Escherichia coli fructosamine 6-kinase (FN6K), an enzyme that phosphorylates fructosamines at C6 and catalyzes the production of the fructosamine 6-phosphate stable intermediate, was generated using the crystal structure of 2-keto-3-deoxygluconate kinase isolated from Thermus thermophilus as template. The putative active site region was then investigated by site-directed mutagenesis to reveal several amino acid residues that likely play important roles in the enzyme reaction. Met220 was identified as a residue that plays a role in substrate recognition when compared to Bacillus subtilis derived FN6K, which shows different substrate specificity from the E. coli FN6K. Among the various Met220-substituted mutant enzymes, Met220Leu, which corresponded to the B. subtilis residue, resulted in an increased activity of fructosyl-valine and decreased activity of fructosyl-lysine, thus increasing the specificity for fructosyl-valine by 40-fold. 相似文献
994.
Shirasawa-Seo N Sano Y Nakamura S Murakami T Gotoh Y Naito Y Hsia CN Seo S Mitsuhara I Kosugi S Ohashi Y 《Plant cell reports》2005,24(3):155-163
The activity of a predicted promoter, PMC8, from Milk vetch dwarf virus was evaluated by comparing it with the cauliflower mosaic virus 35S RNA promoter (P35S) and PNCR, a promoter from Soybean chlorotic mottle virus. When the GUS fusion gene was introduced into tobacco, PMC8 showed a similar expression profile to P35S but with a more intense expression in proliferating tissues. The usefulness of PMC8 was confirmed by driving NPTII for selection of kanamycin-resistant tobacco plants with improved transformation efficiency. PMC8 was also effective in transgenic rice plants. Thus, PMC8 is useful as an alternative to P35S in both dicotyledonous and monocotyledonous plants, especially for gene expression in proliferating tissues. 相似文献
995.
Salicylic acid accumulation under O3 exposure is regulated by ethylene in tobacco plants 总被引:2,自引:0,他引:2
996.
A Dhb-microcystin variant was isolated from the filamentous cyanobacterium Planktothrix rubescens. Its structure was elucidated as (E)-Dhb-microcystin-HilR ([D-Asp3, (E)-Dhb7]microcystin-HilR) on the basis of spectral data and amino acid analysis after acid hydrolysis. 相似文献
997.
The destruction of blood–brain barrier (BBB) and blood-nerve barrier (BNB) has been considered to be a key step in the disease
process of a number of neurological disorders including cerebral ischemia, Alzheimer’s disease, multiple sclerosis, and diabetic
neuropathy. Although glial cell line-derived neurotrophic factor (GDNF) and brain-derived neurotrophic factor (BDNF) facilitate
neuronal or axonal regeneration in the brain or peripheral nerves, their action in the BBB and BNB remains unclear. The purpose
of the present study was to elucidate whether these neurotrophic factors secreted from the brain or peripheral nerve pericytes
increase the barrier function of the BBB or BNB, using our newly established human brain microvascular endothelial cell (BMEC)
line or peripheral nerve microvascular endothelial cell (PnMEC) line. GDNF increased the expression of claudin-5 and the transendothelial
electrical resistance (TEER) of BMECs and PnMECs, whereas BDNF did not have this effect. Furthermore, we herein demonstrate
that the GDNF secreted from the brain and peripheral nerve pericytes was one of the key molecules responsible for the up-regulation
of claudin-5 expression and the TEER value in the BBB and BNB. These results indicate that the regulation of GDNF secreted
from pericytes may therefore be a novel therapeutic strategy to modify the BBB or BNB functions and promote brain or peripheral
nerve regeneration. 相似文献
998.
The DNA from a pituitary adenoma of a patient with multiple endocrine neoplasia (MEN) type 1 was analyzed to detect a point mutation of the Gs alpha gene (gsp) by the PCR direct-sequencing method. The patient had galactorrhea, amenorrhea and acromegalic features. Hormonal examination revealed high serum levels of PRL and GH. The tumor was histologically diagnosed as a mixed GH cell-PRL cell adenoma in which GH and PRL were produced by different cells. Sequence analysis of the DNAs extracted from paraffin sections of pituitary, parathyroid, and pancreas tumors demonstrated the substitution of thymidine for cytidine in codon 201 of the Gs alpha gene that resulted in replacement of arginine (CGT) with cysteine (TGT) only in the pituitary adenoma, but not in the parathyroid and pancreas tumors. These results suggest that a pituitary specific point mutational activation of the Gs alpha gene may be involved in the development of the pituitary adenoma in this patient. 相似文献
999.
A key step towards understanding the development and function of the central nervous system is by characterizing the connections between neurons. Tetanus toxin C fragment (TTC) is transynaptically and retrogradely transported without the toxin's pathogenic effect, and therefore, recently it has been used as a genetic tracer combined with beta-galactosidase or green fluorescent protein. Here, we introduce a new fusion construct, APTTC, consisting of the truncated human placental alkaline phosphatase with TTC, and generating the transgenic mouse line, (tetracycline operator) tetO-APTTC, for inducible expression of APTTC regulated by tetO. We demonstrate that APTTC is transported retrogradely and transynaptically, and allows us to robustly visualize the inputs of the expressing neurons when transgenetically expressed in mice, exemplified in the striatal neuronal circuit. Therefore, tetO-APTTC transgenic mouse line can be widely used for visualization of neuronal connectivity when combined with mice carrying tetracycline-controlled transactivator (tTA) in any specific neurons. 相似文献