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Sashko Spassov Dietmar Pfeifer Karl Strosing Stefan Ryter Matthias Hummel Simone Faller Alexander Hoetzel 《PloS one》2014,9(7)
Recently, we have shown that inhalation of hydrogen sulfide (H2S) protects against ventilator-induced lung injury (VILI). In the present study, we aimed to determine the underlying molecular mechanisms of H2S-dependent lung protection by analyzing gene expression profiles in mice. C57BL/6 mice were subjected to spontaneous breathing or mechanical ventilation in the absence or presence of H2S (80 parts per million). Gene expression profiles were determined by microarray, sqRT-PCR and Western Blot analyses. The association of Atf3 in protection against VILI was confirmed with a Vivo-Morpholino knockout model. Mechanical ventilation caused a significant lung inflammation and damage that was prevented in the presence of H2S. Mechanical ventilation favoured the expression of genes involved in inflammation, leukocyte activation and chemotaxis. In contrast, ventilation with H2S activated genes involved in extracellular matrix remodelling, angiogenesis, inhibition of apoptosis, and inflammation. Amongst others, H2S administration induced Atf3, an anti-inflammatory and anti-apoptotic regulator. Morpholino mediated reduction of Atf3 resulted in elevated lung injury despite the presence of H2S. In conclusion, lung protection by H2S during mechanical ventilation is associated with down-regulation of genes related to oxidative stress and inflammation and up-regulation of anti-apoptotic and anti-inflammatory genes. Here we show that Atf3 is clearly involved in H2S mediated protection. 相似文献
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Nucleotide sequence of the colicin B activity gene cba: consensus pentapeptide among TonB-dependent colicins and receptors. 总被引:21,自引:12,他引:9 下载免费PDF全文
Colicin B formed by Escherichia coli kills sensitive bacteria by dissipating the membrane potential through channel formation. The nucleotide sequence of the structural gene (cba) which encodes colicin B and of the upstream region was determined. A polypeptide consisting of 511 amino acids was deduced from the open reading frame. The active colicin had a molecular weight of 54,742. The carboxy-terminal amino acid sequence showed striking homology to the corresponding channel-forming region of colicin A. Of 216 amino acids, 57% were identical and an additional 19% were homologous. In this part 66% of the nucleotides were identical in the colicin A and B genes. This region contained a sequence of 48 hydrophobic amino acids. Sequence homology to the other channel-forming colicins, E1 and I, was less pronounced. A homologous pentapeptide was detected in colicins B, M, and I whose uptake required TonB protein function. The same consensus sequence was found in all outer membrane proteins involved in the TonB-dependent uptake of iron siderophores and of vitamin B12. Upstream of cba a sequence comprising 294 nucleotides was identical to the sequence upstream of the structural gene of colicin E1, with the exception of 43 single-nucleotide replacements, additions, or deletions. Apparently, the region upstream of colicins B and E1 and the channel-forming sequences of colicins A and B have a common origin. 相似文献
5.
1. Translation of poly(A) RNA extracted from the nervous tissue of locusts in a reticulocyte lysate system led to polypeptides with a broad spectrum of molecular weights. 2. Using anti-locust acetylcholine receptor (AChR) antisera, polypeptides with a molecular weight of about 50,000 were immunoprecipitated. These peptides comprised about 0.3% of the total translation products. 3. Cotranslational incubation with pancreatic rough microsomes resulted in a glycosylated 60,000-dalton immunoprecipitate. 4. Density-gradient analysis of in vitro synthesized and glycosylated receptor polypeptides indicated that no assembly of subunits had taken the place under the in vitro conditions. 相似文献
6.
E Middlekoop E E Van der Hoek E M Bevers P Comfurius A J Slotboom J A Op den Kamp B H Lubin R F Zwaal B Roelofsen 《Biochimica et biophysica acta》1989,981(1):151-160
Crosslinking of membrane skeletal proteins such as spectrin by oxidation of their SH-groups can be provoked by treatment of intact erythrocytes with diamide. Shortly after exposure of human erythrocytes to diamide and despite the transverse destabilization of the lipid bilayer that was observed in these cells (Franck, P.F.H., Op den Kamp, J.A.F., Roelofsen, B. and Van Deenen, L.L.M. (1986) Biochim. Biophys. Acta 857, 127-130), no abnormalities could be detected regarding the asymmetric distribution of the phospholipids when probed by either the prothrombinase assay or brief exposure of the cells to a modified phospholipase A2 with enhanced membrane penetrating capacity. This asymmetry appeared to undergo dramatic changes however, when the ATP content of the cytosol had decreased to less than 10% of its original level during prolonged incubation of the treated cells. These observations indicate that the initial maintenance of phospholipid asymmetry in diamide-treated erythrocytes can be solely ascribed to the action of the ATP-dependent aminophospholipid translocase. This view is supported by experiments involving radiolabeled phospholipids of which trace amounts had been inserted into the outer membrane leaflet of diamide-treated red cells and which still showed a preferential translocation of both aminophospholipids in favour of the inner monolayer, be it that the efficiency of the translocase was found to be impaired when compared to control cells. 相似文献
7.
E Middelkoop A Coppens M Llanillo E E Van der Hoek A J Slotboom B H Lubin J A Op den Kamp L L Van Deenen B Roelofsen 《Biochimica et biophysica acta》1989,978(2):241-248
The ATP-dependent translocation of phospholipids in the plasma membrane of intact Friend erythroleukemic cells (FELCs) was studied in comparison with that in the membrane of mature murine erythrocytes. This was done by following the fate of radiolabeled phospholipid molecules, previously inserted into the outer monolayer of the plasma membranes by using a non-specific lipid transfer protein. The transbilayer equilibration of these probe molecules was monitored by treating the cells--under essentially non-lytic conditions--with phospholipases A2 of different origin. Rapid reorientations of the newly introduced aminophospholipids in favour of the inner membrane leaflet were observed in fresh mouse erythrocytes; the inward translocation of phosphatidylcholine (PC) in this membrane proceeded relatively slow. In FELCs, on the other hand, all three glycerophospholipids equilibrated over both halves of the plasma membrane very rapidly, i.e. within 1 h; nevertheless, an asymmetric distribution in favour of the inner monolayer was only observed for phosphatidylserine (PS). Lowering the ATP-level in the FELCs caused a reduction in the rate of inward translocation of both aminophospholipids, but not of that of PC, indicating that this translocation of PS and phosphatidylethanolamine (PE) is clearly ATP-dependent. Hence, the situation in the plasma membrane of the FELC is rather unique in a sense that, though an ATP-dependent translocase is present and active both for PS and PE, its activity results in an asymmetric distribution of PS, but not of PE. This remarkable situation might be the consequence of the fact that, in contrast to the mature red cell, this precursor cell still lacks a complete membrane skeletal network. 相似文献
8.
Seeds of the root parasitesStriga (several spp.) andBuchnera americana were examined by means of SEM. The surface patterns of the seeds in both genera resemble each other closely, especially those ofS. angustifolia andB. americana. SomeStriga spp. can be clearly distinguished by their surface characteristics, while this is quite difficult in others. The taxonomic value of the seed surface features ofStriga andBuchnera is discussed. 相似文献
9.
Janusz Janiszewski Dietmar Otto 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1988,162(6):739-746
1. | Intracellular recordings of suboesophageal neurons were performed in the cricketGryllus bimaculatus during applied changes of head temperature in the range 8 to 32.5 °C. The temperature was controlled by perfusing the head with Ringer solution of appropriate temperature. Subsequent staining with Lucifer Yellow revealed descending, ascending or T-shaped cells with ventrally located somata (Fig. 1). |
2. | In 6 out of 7 neurons recorded (Fig. 1, neurons A, B, C, D, E, G) the firing rate was correlated with abdominal ventilatory pumping (Fig. 2a, b). These neurons also received input from cereal sensory hairs (Fig. 2c). Furthermore, one of them (Fig. 1, neuron A) showed responses to auditory (Fig. 2d) and another (Fig. 1, neuron E) to visual input (Fig. 2e). |
3. | Activity of every tested neuron was correlated with the temperature of the perfusing Ringer solution: the amplitude and duration of spikes and excitatory postsynaptic potentials increased with cooling (Fig. 3). Two types of temperature-dependent changes in firing rate were identified. In type I the spiking rate was higher at higher temperature (Figs. 4a, b; 5). In type II spiking rate was related to the direction of temperature change (Fig. 4c, d). |
4. | The possible involvement of one of the recorded cells (Fig. 1, neuron F) in thermoreception processes is discussed. Activity of this neuron was not related to the rhythm of abdominal ventilatory pumping, nor did the cell receive cereal, visual or auditory input. Its activity was related mainly to the direction of temperature changes i.e. with an increase in firing rate during cooling, independent of the temperature at which the cooling started and with a transient decrease in firing rate during warming from starting point of 10 °C. |
10.
Spyridon Vamvakas Wolfgang Dekant Dietmar Schiffmann Dietrich Henschler 《Cell biology and toxicology》1988,4(4):393-403
S-(chloroethyl)-cysteine (CEC) and S-(1,2-dichlorovinyl)cysteine (DCVO) have been proposed as intermediates in the metabolic transformation of the carcinogens 1,2-dichloroethane and 1,1,2-trichloroethylene. We have tested the ability of CEC and DCVC to induce DNA repair and genotoxic effects at the chromosomal level by comparative assessment of unscheduled DNA synthesis induction and micronucleus formation in Syrian hamster embryo fibroblasts. CEC induced a potent and dose-dependent response in both assays, whereas DCVC treatment resulted in a comparatively weak induction of DNA repair and failed to raise micronucleus formation above control rates. Inhibition of cysteine conjugate \gB-lyase diminished the effect of DCVC, but had no influence on the genotoxicity of CEC either in the unscheduled DNA synthesis or micronucleus assay.Abbreviations AOAA
aminooxyacetic acid
- CEC
S-(chloroethyl)-cysteine; \gB-lyase, cysteine conjugate -lyase
- DCE
1,2-dichloroethane
- DCVC
S(1,2-dichlorovinyl)-cysteine
- GSH
glutathione
- HU
hydroxyurea
- IBR
IBR-modified Dulbecco's Eagle's reinforced medium
- MN2
micronuclei/2,000 cells
- 4-NQO
4-nitroquinoline-1-oxide
- SHE
Syrian hamster embryo fibroblasts; 3H-Thd, 3H-thymidine
- TCE
1,1,2-trichloroethylene
- UDS
unscheduled DNA synthesis 相似文献