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811.
The effect of black widow spider venom [crude gland extract (CGE), gland lumen venom (GLV), or from direct bite] on the cardiac activity of Periplaneta americana was assayed both in vivo and in vitro. It was shown that these different forms of venom in all cases blocked the cockroach heart-beat. Both CGE and GLV showed a selective activity on the heart function compared with their effect on the CNS. It is suggested that cardiac block is due to impairment of either the cardiac nerve ganglia function or the myocardial neuromuscular junctions, or of both of them. The mode of action of the toxic effects on the heart is discussed. Experiments with antiserum from CGE indicate that the antigenic fractions of CGE and GLV affecting the heart function, as well as those affecting the insect motor functions, are common to both toxic materials. 相似文献
812.
Dr. Dharam V. Ablashi Paul H. Levine Caterina De Vinci James E. Whitman Jr. Giancarlo Pizza Dimitri Viza 《Biotherapy》1996,9(1-3):81-86
Specific Human Herpes virus-6 (HHV-6) transfer factor (TF) preparation, administered to two chronic fatigue syndrome patients,
inhibited the HHV-6 infection. Prior to treatment, both patients exhibited an activated HHV-6 infection. TF treatment significantly
improved the clinical manifestations of CFS in one patient who resumed normal duties within weeks, whereas no clinical improvement
was observed in the second patient. It is concluded that HHV-6 specific TF may be of significant value in controlling HHV-6
infection and related illnesses. 相似文献
813.
Carlo Alberto Palmerini Michela Mazzoni Giancarlo Giovinazzo Giuseppe Arienti 《The Journal of membrane biology》2009,230(3):125-131
Antarctic fish live in very cold water and have adapted to this exceptional environment. Hemoglobin is absent or very low;
yet these fish still have erythrocytes, and from these we prepared ghost-like membranes. We studied for the first time the
lipid composition of ghost membranes and of plasma in Antarctic fish (C. hamatus and T. bernacchii) and compared our results with those obtained for temperate-water fish (C. auratus and A. anguilla taken from Lake Trasimeno, Perugia, Italy). The membranes of Antarctic fish were richer in glycerophospholipid (especially
phosphatidylethanolamine), whereas the membranes of temperate-water fish were richer in sphingomyelin. Unsaturated fatty acids
were particularly abundant in Antarctic fish: C. hamatus had long-chain unsaturated fatty acid (especially C22:6 ω-3), whereas T. bernacchii had shorter unsaturated fatty acyl chains (c16:1, ω-7). On the other hand, C. auratus and A. anguilla were particularly rich in C16:0, which constituted more than one-half of the total fatty acid. Plasma lipids (both phospholipid
and cholesterol) were much more abundant in temperate-water fish. The differences in phospholipid content were mainly due
to choline glycerolipids. Measures of membrane fluidity inferred from the fluorescence anisotropy of DPH indicated that the
membranes from Antarctic fish were more fluid at any measured temperature than those obtained from fish living in temperate
waters. The ability to live in a very cold environment has therefore been achieved by the two Antarctic species tested in
this paper by different strategies, but with the same results on fluidity. 相似文献
814.
815.
Modifications of the higher-order chromatin structure induced by polyamines have been quantitatively investigated in situ through a non-invasive biophysical approach using Differential Scanning Calorimetry and Quantitative Fluorescence Microscopy. Calorimetric and intensitometric profiles have been acquired for samples of native thymocytes, alternatively suspended in buffers, with or without natural polyamines (spermine and spermidine). The results here reported show that the structure and distribution of nuclear chromatin in situ considerably change upon the ionic composition of the environment. A quantitative analysis of this data and a comparison with previous results obtained from isolated chromatin fibers was carried out. Finally, an inverse relationship between chromatin condensation and nuclear volume was observed. 相似文献