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111.
For the purpose of studying a role of immediate early genes in psychotomimetic-induced behavioral excitation, we experimentally enhanced the locomotor activity of mice by acute administration of phencyclidine and examined the expression and localization of the c-Fos-like and c-Jun-like immunoreactivities in brain regions. A single injection of phencyclidine (5.0 mg/kg, i.p.) significantly increased not only the locomotor activity but also the expression of c-Fos-like immunoreactivity in several brain regions, particularly in the parietal cortex, hippocampal dentate gyrus, piriform cortex and hypothalamus. Interestingly, the c-Fos-like immunoreactivity in the parietal cortex continued to increase for 1 week after the phencyclidine injection. These results indicate that phencyclidine, even injected only once, can induce the persistent expression of c-Fos or c-Fos-related protein(s) in the mouse brain, and also suggest the possibility that such a c-Fos expression may underlie the behavioral and/or psychotomimetic effects of phencyclidine.  相似文献   
112.
Previously, investigations using single-fluorescent-molecule tracking at frame rates of up to 65 Hz, showed that the transmembrane MHC class II protein and its GPI-anchored modified form expressed in CHO cells undergo simple Brownian diffusion, without any influence of actin depolymerization with cytochalasin D. These results are at apparent variance with the view that GPI-anchored proteins stay with cholesterol-enriched raft domains, as well as with the observation that both lipids and transmembrane proteins undergo short-term confined diffusion within a compartment and long-term hop diffusion between compartments. Here, this apparent discrepancy has been resolved by reexamining the same paradigm, by using both high-speed single-particle tracking (50 kHz) and single fluorescent-molecule tracking (30 Hz). Both molecules exhibited rapid hop diffusion between 40-nm compartments, with an average dwell time of 1-3 ms in each compartment. Cytochalasin D hardly affected the hop diffusion, consistent with previous observations, whereas latrunculin A increased the compartment sizes with concomitant decreases of the hop rates, which led to an ∼50% increase in the median macroscopic diffusion coefficient. These results indicate that the actin-based membrane skeleton influences the diffusion of both transmembrane and GPI-anchored proteins.  相似文献   
113.
It was found that an optically active copolyester, poly(3-hydroxybutyrate-co-3-hydroxyvalerate), denoted as P(3HB-co-3HV), is synthesized by Alcaligenes eutrophus H16 from several amino acids under various fermentation conditions. The optimum condition for the biosynthesis from one amino acid, threonine, was investigated and its biosynthetic pathway was discussed on the basis of the relation between the fermentation condition and the co-monomer composition of the produced polyesters.  相似文献   
114.
The production of pectinase, the major virulence determinant of soft-rot Erwinia species, is controlled by many regulatory factors. We focused on the major regulatory proteins, KdgR, CRP, Pir, and PecS, characterized mainly in E. chrysanthemi, and tested for their presence and function in the control of pectate lyase (Pel) and polygalacturonase (Peh) production in E. carotovora subsp. carotovora. Homologues of kdgR and crp but not of pir and pecS were detected by Southern blot analyses in E. carotovora subsp. carotovora. In fact, KdgR and CRP homologues of E. carotovora subsp. carotovora had high amino acid identities to those of E. chrysanthemi, including a complete match of the hypothetical helix-turn-helix DNA-binding motif. However, in Western blot analyses using anti-Pir (E. chrysanthemi) antibodies, a cross-reacting protein was present in both Erwinia species, although Pel production in E. carotovora subsp. carotovora was not further stimulated by adding plant extract into the medium containing PGA (polygalacturonic acid) in which hyperinduction by Pir has been reported in E. chrysanthemi EC16. When plasmids that contained each of these regulatory genes from E. chrysanthemi were introduced into E. carotovora subsp. carotovora, Pel production was controlled as predicted from their roles in E. chrysanthemi, except for PecS. PecS exerted a positive control in E. carotovora subsp. carotovora, in contrast to a negative control in E. chrysanthemi. DNA-binding assays demonstrated that KdgR, CRP, Pir, and PecS of E. chrysanthemi and KdgR and CRP homologues of E. carotovora subsp. carotovora could bind to the promoter regions of pel-1, pel-3, and peh of E. carotovora subsp. carotovora. Taken together, KdgR and CRP homologues of E. carotovora subsp. carotovora may regulate Pel and Peh production as in E. chrysanthemi. However, the presence of Pir and PecS homologues in E. carotovora subsp. carotovora was not identified in this study, though these proteins of E. chrysanthemi were functional on the promoter regions of the pectinase genes of E. carotovora subsp. carotovora.  相似文献   
115.
Aiming to get useful steroidal alkaloids by tissue culture of Solanum laciniatum Ait., indefinitely growing callus tissue was prepared from the mother plant. Some nutritional requirements for the growth of the callus tissue were studied. By examining steroidal compounds in callus culture, cholesterol, stigmasterol, β-sitosterol, lanosterol, squalene, diosgenin and a new steroidal alkaloid were found to be formed in the callus culture. The new steroidal alkaloid was found to be solasodine derivative containing rhamnose and other unidentified sugars.  相似文献   
116.
Addition of γ-aminobutyric acid (GABA) and angiotensin converting enzyme (ACE)-inhibitory peptides to the pickles was studied in order to develop a new type of pickles that reduce blood pressure. Based on the outcome of these studies, a new type of fermentation bed composed of rice bran and white miso has been successfully developed. The advantage of such pickles is that they not only contain both GABA and ACE-inhibitory peptides, but also that their taste and flavor are excellent, with colors close to the original ones. The new type of pickles could temporarily reduce blood pressure in two types of rats, spontaneously hypertensive rats and NaCl-sensitive model rats. Thus, the newly developed pickles appear to be beneficial for pickle business.  相似文献   
117.
118.
Background. Phospholipids concentration in the gastric mucosa decreased in patients with Helicobacter pylori infection. The aim of this study is to examine the effects of eradication of H. pylori on decreasing the phospholipids concentration in the gastric mucosa in patients with gastric or duodenal ulcer. Materials and Methods. Phospholipids (phosphatidylcholine, phosphatidylethanolamine, and sphingonomyeline) were measured in biopsy specimens from the antrum and corpus using thin‐layer chromatography. In H. pylori positive patients with gastric ulcer (n = 26) and duodenal ulcer (n = 13), and H. pylori negative controls (n = 20), the biopsy specimens were obtained before and 3 months after eradication. Eradication was performed using lansoprazole, amoxycillin, and clarithromycin. Results. Compared with the H. pylori negative control group, the concentrations of phosphatidylcholine and phosphatidylethanolamine decreased significantly in the gastric ulcer group in both antrum and corpus mucosa, and in the duodenal ulcer group in antrum mucosa. This decrease returned to the control level after eradication. Conclusions. This study demonstrates that the eradication of H. pylori in patients with peptic ulcer normalized the decrease of phosphatidylcholine and phosphatidylethanolamine in the gastric mucosa.  相似文献   
119.
We investigated the role of bacterial internalization in the killing caused by Shiga toxin-producing Escherichia coli (STEC) infection using a gnotobiotic murine model. A high number of internalized STEC was found in the colonic epithelial cells of STEC-infected mice by both an ex vivo assay and transmission electron microscopy. Most of these mice were killed within 10 days after infection. However, the implantation of lactic acid bacteria in such mice before infection markedly decreased the number of internalized STECs and also completely protected these hosts from killing by a STEC infection. The inhibition of such internalization by immunoglobulin also prevented the hosts from being killed. The Shiga toxin levels in these hosts indicated an inhibition of the penetration of Shiga toxins produced in the colon to the underlying tissue. These results suggested that the internalization plays an important role in the pathogenicity caused by STEC infection in a gnotobiotic murine model.  相似文献   
120.
Non-human primates are frequently used in toxicological studies the result of which are extrapolated to humans, but background data on drug metabolism ability among monkeys derived from different countries has not been published, especially on the key enzyme, cytochrome P450 (CYP450). We assessed the amounts of hepatic CYP450 obtained from cynomolgus monkeys of different ages and from different countries in this study. There were no regional differences of total P450 content, as well as major CYP450 isozymes (CYP 1A, 2A, 2B, 2C, 2D, 2E1 and 3A4) in cynomolgus monkeys by westernblot analysis. Similarly, there were no significant differences with hybrid cynomolgus monkeys, but variations in individual values were large. As for aging, total P450 contents declined in old cynomolgus monkeys (12-32 years of age). These results indicate the usefulness of basic data of hepatic CYP450 obtained from cynomolgus monkeys of different ages and from different countries.  相似文献   
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