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41.
Allozyme variations at ten loci, in a few species belonging to four different subgroups of the immigrans species group have been studied. The biochemical phylogeny of these species revealed two main lineages. In one of these main lineages, D. n. nasuta, D. n. albomicans and D. s neonasuta constitute one group while D. immigrans and D. formosana comprise another group. The other main lineage includes D. rubida, D. pararubida, D. hypocausta and D. lineosa. 相似文献
42.
Studies were made of the effects of maternal thiamine deficiency on rat whole brain, gray matter and white matter lipids. Mothers were fed a high protein diet (controls) or thiamine deficient high protein diet (thiamine deficient, TD) from 14th day of gestation through lactation. An additional group (pair fed control, PFC) was pair fed with the thiamine deficient group. The TD pups started showing symptoms of abnormalities in posture, arched back and hind limb paralysis from 16th day of lactation. Significant deficits were found in body weight and brain weight of TD and PFC pups. But the deficits seem to be more in the former group. Significant deficits were observed with regard to the concentration of lipids such as galactolipids, phospholipids and plasmalogens in the whole brain of TD and PFC pups at 21 days of age. Additional deficits were also found in the concentration of cholesterol in PFC pups. Gray matter lipids from TD pups seem to be completely spared. However, deficits were found in galactolipid and ganglioside concentrations in PFC pups. The deficits found in the concentration of different lipids in white matter are similar to those observed in whole brain. These results suggest that the effects of thiamine deficiency may be partly due to resultant growth retardation and partly due to the deficiency of thiamine per se. 相似文献
43.
V.R. Ramakrishnan S. Yabuki I.-Y. Sillers D.G. Schindler D.M. Engelman P.B. Moore 《Journal of molecular biology》1981,153(3):739-760
A map of the positions of 12 of the 21 proteins of the 30 S ribosomal subunit of Escherichia coli (S1, S3, S4, S5, S6, S7, S8, S9, S10, S11, S12 and S15), based on neutron scattering, is presented and discussed. Estimates for the radii of gyration of these proteins in situ are also obtained. It appears that many ribosomal proteins have compact configurations in the particle. 相似文献
44.
45.
P. K. Asha M. S. Shaila C. S. Vaidyanathan T. Ramakrishnan 《Journal of biosciences》1979,1(3):327-334
Treatment ofTrigonella foenumgraeceum (fenugreek) seedlings with naphthalene acetic acid plus gibberellic acid enhanced the RNA synthesising capacity of nuclei
isolated from the hypocotyl and cotyledonary regions. This increase was more pronounced in the nuclei from the hypocotyl region
than from the cotyledonary region.In vitro addition of these phytohormones did not stimulate RNA synthesis by nuclei. The RNA synthesis by mitochondria was not affected
by preincubating the seedlings with the hormones. The nuclei isolated from callus cultures of fenugreek hypocotyl treated
with the hormone also showed increased RNA synthesis. 相似文献
46.
47.
The isolation and structure determination of a glycosidic germacradienolide from Eupatorium altissimum are reported. Eupatorin and 5-hydroxy-3′,4′,6,7-tetramethoxyflavone were also found. 相似文献
48.
49.
Arjun H. Ananth Natarajan Manikandan Ravi Kumar Rajan Ramakrishnan Elancheran Kunasekaran Lakshmithendral Muthiah Ramanathan Atanu Bhattacharjee Senthamaraikannan Kabilan 《化学与生物多样性》2020,17(2)
Breast Cancer (BCa) is the most often diagnosed cancer among women who were in the late 1940’s. Breast cancer growth is largely dependent on the expression of estrogen and progesterone receptor. Breast cancer cells may have one, both, or none of these receptors. The treatment for breast cancer may involve surgery, hormonal therapy (Tamoxifen, an aromatase inhibitor, etc.) and oral chemotherapeutic drugs. The molecular docking technique reported the findings on the potential binding modes of the 2‐(2‐bromo‐3‐nitrophenyl)‐5‐phenyl‐1,3,4‐oxadiazole derivatives with the estrogen receptor (PDB ID: 3ERT). The 1,3,4‐oxadiazole derivatives 4a – 4j have been synthesized and described by spectroscopic method. 2‐(2‐Bromo‐6‐nitrophenyl)‐5‐(4‐bromophenyl)‐1,3,4‐oxadiazole ( 4c ) was reconfirmed by single‐crystal XRD. All the compounds have been tested in combination with generic Imatinib pharmaceutical drug against breast cancer cell lines isolated from Caucasian woman MCF‐7, MDA‐MB‐453 and MCF‐10A non‐cancer cell lines. The compounds with the methoxy (in 4c ) and methyl (in 4j ) substitution were shown to have significant cytotoxicity, with 4c showing dose‐dependent activation and decreased cell viability. The mechanism of action was reported by induced apoptosis and tested by a DNA enzyme inhibitor experiment (ELISA) for Methyl Transferase. Molecular dynamics simulations were made for hit molecule 4c to study the stability and interaction of the protein?ligand complex. The toxicity properties of ADME were calculated for all the compounds. All these results provide essential information for further clinical trials. 相似文献