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991.
Ouabain-stimulated trafficking regulation of the Na/K-ATPase and NHE3 in renal proximal tubule cells
Yan Y Haller S Shapiro A Malhotra N Tian J Xie Z Malhotra D Shapiro JI Liu J 《Molecular and cellular biochemistry》2012,367(1-2):175-183
We have demonstrated that ouabain regulates protein trafficking of the Na/K-ATPase α1 subunit and NHE3 (Na/H exchanger, isoform 3) via ouabain-activated Na/K-ATPase signaling in porcine LLC-PK1 cells. To investigate whether this mechanism is species-specific, ouabain-induced regulation of the α1 subunit and NHE3 as well as transcellular (22)Na(+) transport were compared in three renal proximal tubular cell lines (human HK-2, porcine LLC-PK1, and AAC-19 originated from LLC-PK1 in which the pig α1 was replaced by ouabain-resistant rat α1). Ouabain-induced inhibition of transcellular (22)Na(+) transport is due to an ouabain-induced redistribution of the α1 subunit and NHE3. In LLC-PK1 cells, ouabain also inhibited the endocytic recycling of internalized NHE3, but has no significant effect on recycling of endocytosed α1 subunit. These data indicated that the ouabain-induced redistribution of the α1 subunit and NHE3 is not a species-specific phenomenon, and ouabain-activated Na/K-ATPase signaling influences NHE3 regulation. 相似文献
992.
Liu WQ Tian MX Wang YP Zhao Y Zou NL Zhao FF Cao SJ Wen XT Liu P Huang Y 《Molecular biology reports》2012,39(4):3611-3618
Newcastle disease virus (NDV) is an important pathogen hazardous to poultry industry, and the pathogenicity of NDV strains
varies with different virulence. Peripheral blood serves as an important producer and carrier of viruses and cytokines in
NDV infection. In order to explore the difference of cytokine expression in the peripheral blood between velogenic strain
and lentogenic strain infection, NDV virulent strain F48E9 and vaccine strain Lasota were used to infect specific-pathogen-free
(SPF) chickens separately, and peripheral blood was collected on 0, 3, 7, 10, 14, and 21 days post-infection (d.p.i.). Real-time
PCR was then used to detect the expression of six kinds of immune-related cytokine genes. For the F48E9 group, a sharp increase
of the expression of interferon-alpha (IFN-α), interferon-gamma (IFN-γ), interleukin-16 and IL-18 was observed on 3 d.p.i.
before the NDV blood peak (7 d.p.i.), followed by a rapid decline to the level lower than that of control group, then the
expression of IFN-α increased slowly and reached or exceeded the level of control group in the later phase of the infection,
while the expression of IFN-γ, IL-16, and IL-18 fluctuated at the level of control group for the rest of study period. The
increase of IL-2 expression was not obvious, and no increase of IL-15 expression was noted. For the Lasota (vaccine) group,
the picture was quite different, a sharp increase of IFN-γ (but not IFN-α), IL-2 was observed on 7 d.p.i. before the NDV blood
peak (10 d.p.i.). On the contrary, there was no dramatic increase of IL-16 and IL-18. Interestingly, in contrast to the F48E9
group, there was an increase of IL-15 on day 10 d.p.i., but it remained modest. There was also an increase of IFN-α on day
21 d.p.i. Our results revealed that infection with NDV strains of different virulence was associated with distinct cytokine
expression patterns in peripheral blood, modulation of cytokine responses may play a key role in mediation of NDV pathogenesis. 相似文献
993.
994.
Chang-Yan Zhou Yong-Sheng Tian Zhi-Sheng Xu Wei Zhao Chen Chen Wen-Hua Bao Lin Bian Run Cai Ai-Zhong Wu 《Molecular biology reports》2012,39(12):10939-10947
Applying the genomic library construction strategy and colony screening, a new aroA gene encoding 5-enolpyruvylshikimate-3-phosphate synthase has been identified, cloned and overexpressed in Escherichia coli, and the enzyme was purified to homogeneity. Kinetic analysis of the AroA P.fluorescens indicated that the full-length enzyme exhibits 10-fold increased IC50 and an approximately 38-fold increased K i for glyphosate compared to those of the AroA E.coli , while retaining high affinity for the substrate phosphoenolpyruvate. Furthermore, we have transformed the new aroA P.fluorescens gene into Arabidopsis thaliana via a floral dip method, and demonstrated that transgenic A. thaliana plants exhibit significant glyphosate resistance when compared with the wild type. 相似文献
995.
996.
Han R Wei Y Kang X Chen H Sun G Li G Bai Y Tian Y Huang Y 《Molecular biology reports》2012,39(3):3153-3160
The PR domain containing 16 (PRDM16) is a member of the Prdm family, and is known to regulate cell differentiation. In the
present study, DNA pool sequencing methods were employed to screen genetic variations in the chicken PRDM16 gene. The results revealed four novel single nucleotide polymorphisms (SNPs): NC_006108.2: g.92188G>A, XM_417551: c.1161C>T
(Ala/Ala, 387aa), c.1233C>T (Ser/Ser, 411aa) and c.1433G>A (Ser/Asn, 478aa). The BglI polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) was used to detect c.1161C>T, while HhaI Forced PCR-RFLP methods were used to detect 1233C>T and c.1433G>A in 964 chickens. The chickens comprised 38 grandparents,
66 F1 parents and 860 F2 birds derived from an F2 resource population of Gushi chickens crossed with Anka broilers. The associations of the polymorphisms in the chicken PRDM16 gene with performance traits were analyzed in the 860 F2 chickens. The results indicated that the three SNPs were significantly associated with growth, fatness and meat quality traits
in the chickens. In particular, the polymorphisms of the missense SNP (c.1433G>A) had positive effects on chicken body weight
and body size at different stages. It affected also fatness traits significantly. Comparison of the different genotypes of
c.1433G>A showed that the GG genotype favored chicken growth and fatness traits. 相似文献
997.
Currently, it is unclear which index of haematological parameters could be used to most easily monitor iron deficiency during endurance training. To address this question, 16 male Wistar rats were randomly assigned to two groups: a sedentary group (n = 8) and an exercised group (n = 8). Initially, animals in the exercise group started running on a treadmill at a rate of 30 m/min, on a 0% grade, for 1 min/session. Running time was gradually increased by 2 min/day. The training plan was one session per day during the initial 2 weeks and two sessions per day during the third to ninth week. At the end of the 9-week experiment, we analysed the blood of the experimental animals for haemoglobin levels, erythrocyte numbers, haematocrit, serum iron levels, total iron binding capacity, transferrin saturation, serum ferritin levels and soluble transferrin receptor (sTfR) levels, and we calculated the ratio of sTfR/ferritin. Erythrocyte numbers, haemoglobin levels and haematocrit values were decreased after 9 weeks of exercise, but sTfR and sTfR/ferritin values were increased (P < 0.01 or P < 0.05). The training regime significantly increased TfR mRNA levels in the bone marrow cells of the exercised rats compared with the sedentary group (1.8 ± 0.5 vs. 1.1 ± 0.2, P < 0.01). These results revealed a significant correlation between TfR levels in the bone marrow cells and the ratio of sTfR/ferritin (r = 0.517; P < 0.01) and sTfR levels (r = 0.206; P < 0.05) in sedentary and exercised rats. In conclusion, we show that sTfR indices and the ratio of sTfR/ferritin could be useful indicators for monitoring iron deficiency during endurance training. 相似文献
998.
The physiological significance of photosystem II (PSII) core protein phosphorylation has been suggested to facilitate the migration of oxidative damaged D1 and D2 proteins, but meanwhile the phosphorylation seems to be associated with the suppression of reactive oxygen species (ROS) production, and it also relates to the degradation of PSII reaction center proteins. To more clearly elucidate the possible protecting effect of the phosphorylation on oxidative damage of D1 protein, the degradation of oxidized D1 protein and the production of superoxide anion in the non-phosphorylated and phosphorylated PSII membranes were comparatively detected using the Western blotting and electron spin resonance spin-trapping technique, respectively. Obviously, all of three ROS components, including superoxide anion, hydrogen peroxide and hydroxyl radical are responsible for the degradation of oxidized D1 protein, and the protection of the D1 protein degradation by phosphorylation is accompanied by the inhibition of superoxide anion production. Furthermore, the inhibiting effect of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), a competitor to Q(B), on superoxide anion production and its protecting effect on D1 protein degradation are even more obvious than those of phosphorylation. Both DCMU effects are independent of whether PSII membranes are phosphorylated or not, which reasonably implies that the herbicide DCMU and D1 protein phosphorylation probably share the same target site in D1 protein of PSII. So, altogether it can be concluded that the phosphorylation of D1 protein reduces the oxidative damage of D1 protein by decreasing the production of superoxide anion in PSII membranes under high light. 相似文献
999.
Application of pyrosequencing of six Salmonella-specific genes as a rapid Salmonella identification method was tested. Primers for hns, hisJ and hilA had non-specific reactions with non-Salmonella strains. Primers for invA, iroB and fimY had specific PCR products and pyrosequences of Salmonella, suggesting that they were suitable for Salmonella rapid identification. 相似文献
1000.
Hou X Tian H Wu J Tao J Chen Y Yin S Zhang K Shang Y Liu X 《Journal of biotechnology》2012,161(3):221-227
The E2 envelope glycoprotein is the major immunodominant protein of classical swine fever virus (CSFV), and can induce neutralizing antibodies and protective immune responses in infected swine. We developed a tandem-repeat multiple-epitope recombinant protein that contains two copies of each of the regions of E2 spanned by residues 693-704, 770-780, and 826-843, coupled by two copies of the region spanned by residues 1446-1460 of the CSFV nonstructural protein NS2-3. The chemically synthesized gene was expressed in Escherichia coli as a fusion with glutathione S-8 (GST), named GST-BT21. After it was purified with Glutathione Sepharose 4B, we used Western blotting to characterize the construct and surface plasmon resonance to analyze its affinity and specific interaction with CSFV-positive serum. Purified GST-BT21 protein displayed excellent immunoreactivity with antiserum against CSFV (Tian et al., 2012), and surface plasmon resonance confirmed the specific affinity between BT21, but not GST, and antibodies in serum from animals infected with CSFV. Surface plasmon resonance is a sensitive and precise method for epitope evaluation, and it can be used to characterize the immunogenicity and functions of recombinant proteins. 相似文献