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181.
Radha Vaddavalli Sneha Peddi Srilekha Yadav Kothagauni Venkateswar Rao Linga 《Antonie van Leeuwenhoek》2014,105(3):443-450
A novel actinomycete strain, designated VRC07T, was isolated from a Callistemon citrinus rhizosphere sample collected from Hyderabad, India. Its taxonomic status was determined by using polyphasic approach. It is a Gram-positive, aerobic, non-motile, weakly acid-fast strain. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that strain VRC07T is a member of the genus Nocardia. The highest levels of 16S rRNA gene sequence similarity was found between the strains Nocardia niwae W9241T (99.6 %), Nocardia amikacinitolerans W9988T (99.3 %) and Nocardia arthritidis IFM 10035T (98.9 %); similarity to other type strains of the genus Nocardia was below 98.7 %. The organism had chemical and morphological features consistent with its classification in the genus Nocardia such as meso-diaminopimelic acid as the diagnostic diamino acid in the cell wall peptidoglycan. Arabinose and galactose as the diagnostic sugars. Diagnostic polar lipids were phosphatidylinositol, diphosphatidylglycerol, and phosphatidylglycerol. The predominant menaquinone was MK-8(H4, ω-cycl). The major fatty acids were C16:0, C18:0, C18:1 w9c, C18:0 10-methyl TBSA and sum in feature 3 (16:1 w7c/16:1 w6c). The G+C content of the genomic DNA was 68.5 mol%. The DNA–DNA relatedness data, together with phenotypic differences clearly distinguished the isolate from its closest relatives. On the basis of these phenotypic and genotypic data, the isolate represents a novel species, for which the name Nocardia bhagyanesis sp. nov., is proposed. The type strain is VRC07T (=KCTC 29209T = MTCC 11725T = ATCC BAA-2548). 相似文献
182.
Prabodh K. Bajpai Ashish R. Warghat Ram Kumar Sharma Ashish Yadav Anil K. Thakur Ravi B. Srivastava Tsering Stobdan 《Biochemical genetics》2014,52(3-4):137-152
Sequence-related amplified polymorphism markers were used to assess the genetic structure in three natural populations of Morus alba from trans-Himalaya. Multilocation sampling was conducted across 14 collection sites. The overall genetic diversity estimates were high: percentage polymorphic loci 89.66%, Nei’s gene diversity 0.2286, and Shannon’s information index 0.2175. At a regional level, partitioning of variability assessed using analysis of molecular variance (AMOVA), revealed 80% variation within and 20% among collection sites. Pattern appeared in STRUCTURE, BARRIER, and AMOVA, clearly demonstrating gene flow between the Indus and Suru populations and a geographic barrier between the Indus-Suru and Nubra populations, which effectively hinders gene flow. The results showed significant genetic differentiation, population structure, high to restricted gene flow, and high genetic diversity. The assumption that samples collected from the three valleys represent three different populations does not hold true. The fragmentation present in trans-Himalaya was more natural and less anthropogenic. 相似文献
183.
Deepak Singh Archana Kumari S. Ramaswamy Gurunath Ramanathan 《Biochemical and biophysical research communications》2014
3-Nitotoluene dioxygenase (3-NTDO) is the first enzyme in the degradation pathway of 3-nitrotoluene (3-NT) by Diaphorobacter sp. strain DS2. The complete gene sequences of 3-NTDO were PCR amplified from genomic DNA of Diaphorobacter sp., cloned, sequenced and expressed. The 3-NTDO gene revealed a multi component structure having a reductase, a ferredoxin and two oxygenase subunits. Clones expressing the different subunits were constructed in pET21a expression vector system and overexpressed in E. coli BL21(DE3) host. Each subunit was individually purified separately to homogeneity. The active recombinant enzyme was reconstituted in vitro by mixing all three purified subunits. The reconstituted recombinant enzyme could catalyse biotransformations on a variety of organic aromatics. 相似文献
184.
Deepak Mittal Fabiana Saccheri Emilie Vénéreau Tobias Pusterla Marco E Bianchi Maria Rescigno 《The EMBO journal》2010,29(13):2242-2252
Skin cancers are the most commonly diagnosed cancers. Understanding what are the factors contributing to skin tumour development can be instrumental to identify preventive therapies. The myeloid differentiation primary response gene (MyD)88, the downstream adaptor protein of most Toll‐like receptors (TLR), has been shown to be involved in several mouse tumourigenesis models. We show here that TLR4, but not TLR2 or TLR9, is upstream of MyD88 in skin tumourigenesis. TLR4 triggering is not dependent on lipopolysaccharide associated to skin‐colonizing bacteria, but on the high mobility group box‐1 protein (HMGB1), an endogenous ligand of TLR4. HMGB1 is released by necrotic keratinocytes and is required for the recruitment of inflammatory cells and for the initiation of inflammation. The expression of TLR4 on both bone marrow‐derived and radioresistant cells is necessary for carcinogenesis. Consistently, a human tissue microarray analysis showed that melanoma and colon cancer display an over‐expression of TLR4 and its downstream adaptor protein MyD88 within tumours. Together, our results suggest that the initial release of HMGB1 triggers a TLR4‐dependent inflammatory response that leads to tumour development. 相似文献
185.
Archana Mathur Ajay Kumar Mathur Anita Gangwar Sharawan Yadav Priyanka Verma Rajender Singh Sangwan 《In vitro cellular & developmental biology. Plant》2010,46(1):13-21
A root-derived callus line of Panax sikkimensis that stably accumulates anthocyanins was established by small cell aggregate selection method. The selected line showed a
growth index of 221.36 and an anthocyanin content of 2.76 mg/g fw (7.076% dw) in 50–60 d of growth on a modified MS medium
containing 4.5 μM 2,4-dichlorophenoxy acetic acid and 1.2 μM kinetin under 16-h light and 8-h dark photoperiodic conditions.
Incubation under continuous light increased the growth index to 435.57 but led to a marginal dilution of anthocyanin content
to 2.192 mg/g fw (6.928% dw). The purple-red pigment had absorption maximum at 528 nm. The selected callus line has shown
sustained growth and productivity for more than 6 yr now. Interestingly, pigment accumulation in the selected line did not
hinder the ginsenoside production in the callus tissue (0.9–1.2% fw). 相似文献
186.
187.
Ram Chandra Sangeeta Yadav Ram Naresh Bharagava 《World journal of microbiology & biotechnology》2010,26(4):685-692
This study deals with the optimization of bacterial degradation of pyridine raffinate by previously isolated two aerobic bacteria ITRCEM1 (Bacillus cereus) and ITRCEM2 (Alcaligens faecalis) with accession number DQ4335020 and DQ435021, respectively. The degradation of pyridine raffinate was studied by axenic and mixed bacterial consortium at different nutritional and environmental conditions after the removal of formaldehyde from pyridine raffinate (FPPR). Results revealed that the optimum degradation of pyridine raffinate was observed by mixed bacterial culture in presence of glucose (1% w/v) and peptone (0.2% w/v) at 20% FPPR, pH 7.0, temperature 30°C and 120 rpm at 168 h incubation period . The HPLC analysis of degraded pyridine raffinate samples has indicated the complete removal of α, β and γ picoline. Further, the GC–MS analysis of FPPR pyridine raffinate has shown the presence of pyrazine acetonitrile (6.74), 1,3-dioxepin (8.68), 2-pyridine carboxaldehyde (11.26), propiolactone (12.06), 2-butanol (13.10), benzenesulfonic acid (16.22) and 1,4-dimethyl pyperadine while phenol (17.64) and 3,4-dimethyl benzaldehyde as metabolic products of FPPR. 相似文献
188.
Das B Chowdhury C Kumar D Sen R Roy R Das P Chatterjee M 《Bioorganic & medicinal chemistry letters》2010,20(23):6947-6950
A series of analogues of andrographolide, prepared through chemo-selective functionalization at C14 hydroxy, have been evaluated for in vitro cytotoxicities against human leukemic cell lines. Two of the analogues (6a, 9b) exhibited significant potency. Preliminary studies on structure-activity relationship (SAR) revealed that the α-alkylidene-γ-butyrolactone moiety of andrographolide played a major role in the activity profile. The structures of the analogues were established through spectroscopic and analytical data. 相似文献
189.
Tanis SP Plewe MB Johnson TW Butler SL Dalvie D DeLisle D Dress KR Hu Q Huang B Kuehler JE Kuki A Liu W Peng Q Smith GL Solowiej J Tran KT Wang H Yang A Yin C Yu X Zhang J Zhu H 《Bioorganic & medicinal chemistry letters》2010,20(24):7429-7434
HIV-1 integrase is one of three enzymes encoded by the HIV genome and is essential for viral replication, and HIV-1 IN inhibitors have emerged as a new promising class of therapeutics. Recently, we reported the discovery of azaindole hydroxamic acids that were potent inhibitors of the HIV-1 IN enzyme. N-Methyl hydroxamic acids were stable against oxidative metabolism, however were cleared rapidly through phase 2 glucuronidation pathways. We were able to introduce polar groups at the β-position of the azaindole core thereby altering physical properties by lowering calculated log D values (c Log D) which resulted in attenuated clearance rates in human hepatocytes. Pharmacokinetic data in dog for representative compounds demonstrated moderate oral bioavailability and reasonable half-lives. These ends were accomplished without a large negative impact on enzymatic and antiviral activity, thus suggesting opportunities to alter clearance parameters in future series. 相似文献
190.