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221.
Effect of ethanol administration on the severity of myocardial infarction induced by isoproterenol in rats was studied. Even though serum CPK and GOT levels as well as the extent of myocardial damage as revealed by histopathological studies, were similar, the survival rate was higher in rats administered ethanol. Concentration of cholesterol and triglycerides in the serum and heart in rats given ethanol and isoproterenol seems to be the additive effect caused individually by ethanol and isoproterenol. Myocardial alcohol dehydrogenase and aldehyde dehydrogenase both showed increased activity in rats treated with ethanol. The rate of recovery from myocardial infarction however, was slower in rats treated with ethanol as judged from the serum CPK value. 相似文献
222.
Sushma R. Dhingra S. Duraiswami Narender Kumar Lakshmi G. Kumari 《Journal of biosciences》1989,14(2):79-90
Studies on the characterization of inhibin and inhibin-like factors have depended for the most part on the classicalin vitro pituitary cell culture assay. A major drawback with this assay is the turn-around time which is in the order of two weeks
and consequently slows down purification efforts. The 24 h bioassay for inhibin has been found to be sufficiently sensitive
and also statistically valid. Unfortunately, based as it is on a secondary response, ambiguities arise in interpreting the
results. By including a parallel assay in which the mice are primed with human menopausal gonadotropin rather than human chorionic
gonadotropin, it was possible to device the coupled bioassay. This enables distinguishing inhibin-like factors acting to suppress
pituitary follicle stimulating hormone output from those acting at the level of gonads. In this study the coupled assay for
inhibin has been compared with the classical pituitary cell culture assay in order to assess its biological and statistical
validity. The data validates the bioassay on both the above counts and when considered in conjunction with the short turn-around
time suggests that this assay can be highly useful in studies on isolation of inhibin from various sources. 相似文献
223.
224.
DNA sequence and structure play a key role in imparting fragility to different regions of the genome. Recent studies have shown that non-B DNA structures play a key role in causing genomic instability, apart from their physiological roles at telomeres and promoters. Structures such as G-quadruplexes, cruciforms, and triplexes have been implicated in making DNA susceptible to breakage, resulting in genomic rearrangements. Hence, techniques that aid in the easy identification of such non-B DNA motifs will prove to be very useful in determining factors responsible for genomic instability. In this study, we provide evidence for the use of primer extension as a sensitive and specific tool to detect such altered DNA structures. We have used the G-quadruplex motif, recently characterized at the BCL2 major breakpoint region as a proof of principle to demonstrate the advantages of the technique. Our results show that pause sites corresponding to the non-B DNA are specific, since they are absent when the G-quadruplex motif is mutated and their positions change in tandem with that of the primers. The efficiency of primer extension pause sites varied according to the concentration of monovalant cations tested, which support G-quadruplex formation. Overall, our results demonstrate that primer extension is a strong in vitro tool to detect non-B DNA structures such as G-quadruplex on a plasmid DNA, which can be further adapted to identify non-B DNA structures, even at the genomic level. 相似文献
225.
Comment on: Lignitto L, et al. Nat Cell Biol 2011; 13:412-22. 相似文献
226.
Experiments were conducted on tomato to study the potential of brown alga Sargassum johnstonii as a biofertilizer. Seaweed extract was applied as a foliar spray, soil drench, and soil drench + foliar spray to assess
its effect on plant growth, yield, and concentration of lycopene and vitamin C. The main objective of the study was to enhance
the biochemical constituents with neutraceutical and antioxidant values in tomato fruit. Different concentrations (0.1%, 0.4%,
0.8%, 2%, 6%, 8%, and 10%; v/v) of seaweed extract were used and growth was observed over a period of 7 months. A total of 14 sprays/drenches were applied
at 15-day intervals during the entire vegetative and reproductive phase. A statistically significant increase in vegetative
growth (plant height, shoot length, root length, and number of branches), reproductive parameters (flower number, fruit number,
and fresh weight), and biochemical constituents (photosynthetic pigments, proteins, total soluble sugars, reducing sugars,
starch, phenols, lycopene, and vitamin C) was recorded following all three methods of treatment at higher concentrations of
seaweed extract. The study also reports auxin- and cytokinin-like activity, and the presence of macro- (Ca, Mg, Na, and K)
and micronutrients (Fe, Cu, Zn, and Mn), in seaweed extract of S. johnstonii, which makes it a potential biofertilizer. 相似文献
227.
Pravati Kumari Mahapatra Priyambada Mohanty-Hejmadi 《Development, growth & differentiation》1994,36(3):307-317
In this study the effects of vitamin A on tadpoles of Polypedates maculatus with an amputated tail were investigated. After amputation of half the tail at the hindlimb-bud stage, tadpoles were exposed to vitamin A (palmitate) 10 IU/ml solution for 24 hr (Group I), 48 hr (II), 72 hr (III), 96 hr (IV), 120 hr (V) or 144 hr (VI). Vitamin A was deleterious to survival of the tadpoles since 10, 30 and 30% tadpoles died from Group IV, V and VI, respectively before the emergence of forelimbs. Regeneration of the tail was abnormal in 91.7% of the tadpoles. Vitamin A induced homeotic transformation of the amputated tail to hindlimbs in 11.6% of the animals. Normal limb development was suppressed partially or completely in 48.3% tadpoles. These results indicate that in addition to traumatic effects, vitamin A can lead to homeotic transformation of the tail into hindlimbs and can also interfere with normal development of limbs. 相似文献
228.
The ability of cholesterol derivatives without a hydroxyl group or a side-chain, to support the growth of heme and cyclase deficient Saccharomyces cerevisiae mutant GL 7 was tried and found to be in conformity with the results obtained using liposomes. On the other hand, results with other Ring A modified steroids involving saturation or movement of C5-C6 double bond, or isomeric 3-hydroxy-3-methyl cholestane derivatives, indicated that even minor structural variations can cause considerable changes in their growth supporting potential. The consequence of such structural variations need not be obviated by studies using liposomes or vesicles. 相似文献
229.
Payal Singh Nilesh Kumar Minesh Jethva Saurabh Yadav Pragati Kumari Archana Thakur Hemant Ritturaj Kushwaha 《Physiology and Molecular Biology of Plants》2018,24(2):315-324
Cyanobacteria are one of the ancient bacterial species occupying a variety of habitats with diverse metabolic preferences. RNA regulators like riboswitches play significant role in controlling the gene expression in prokaryotes. The taxonomic distribution of riboswitches suggests that they might be one of the oldest mechanisms of gene control system. In this paper, we analyzed the distribution of different riboswitch families in various cyanobacterial genomes. It was observed that only four riboswitch classes were abundant in cyanobacteria, B12-element (Cob)/AdoCbl/AdoCbl-variant riboswitch being the most abundant. The analysis suggests that riboswitch mode of regulation is present in cyanobacterial species irrespective of their habitat types. A large number of unidentified genes regulated by riboswitches listed in this analysis indicate the wide range of targets for these riboswitch families. The analysis revealed a large number of genes regulated by riboswitches which may assist in elaborating the diversity among the cyanobacterial species. 相似文献
230.
George Britton Raj Kumari Singh Trevor W. Goodwin Avraham Ben-Aziz 《Phytochemistry》1975,14(11):2427-2433
The presence of β-carotene, lycopene, rhodopin, rhodovibrin, anhydrorhodovibrin, spirillox-anthin, ‘monodemethylated spirilloxanthin’ and ‘dihy 相似文献