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131.
Previous study in our laboratory confirmed that a novel polypeptide, CS5931 derived from Ciona savignyi possesses potent antitumor activity. In the present study, the full length cDNA of CS5931 precursor, termed Cs-pgrn-1 was cloned. The complete cDNA sequence of this gene consists of 685 bp containing an open reading frame (ORF) of 522 bp (173 amino acid residues). In silico analysis revealed that the polypeptide consists of two identical domains, similar with granulin (GRN) found in other species, and each of the domain encodes a polypeptide identical with CS5931. Phylogenetic analysis confirmed that CS5931 shares high homology with Ciona intestinalis GRN and is conserved during evolution. The polypeptide also shows high similarity with human GRN A, B, and C. Prediction of 3D protein structure revealed the 3D structure of CS5931 is very similar with human GRN A. The CS5931 was expressed using a prokaryotic expression system and the purified polypeptide inhibited the growth of several tumor cell lines in vitro via apoptotic pathway. Our study revealed that CS5931 has the potential to be developed as a novel antitumor agent.  相似文献   
132.
The over-expression of tissue factor (TF) and its roles in colon cancer progression have attracted much attention. However, the mechanisms regulating TF expression have not yet been shown in detail. In this study, we over-expressed miR-19a, miR20a and miR-106b in colon cancer cells, and evaluated their impact on TF expression and cellular function. We provide evidence demonstrating that miR-19a inhibited TF expression in vitro. Luciferase reporter assay confirmed that TF was a direct target of miR-19a because the miR-19a mediated repression of luciferase activity was abolished by mutation of the putative binding site. Moreover, miR-19a suppressed colon cancer cell migration and invasion. This effect was due to the indirect down-regulation of matrix metalloproteinase 9. Finally, we investigated the relevance of TF and miR-19a expression in a total of 48 paired colon cancer samples and revealed that miR-19a was inversely correlated with TF expression in stages I and II cases. Therefore, our results suggested that miR-19a was capable of suppressing TF expression in vitro and inhibiting cell migration and invasion. Although it was not the unique mechanism responsible for the expression of TF in vivo, miR-19a was inversely correlated with TF expression in early stage colon cancer patients.  相似文献   
133.
以单头亚菊茎段为外植体对其进行组织培养,MS为基本培养基,设置不同激素浓度配比。对实验结果进行观察分析,筛选出合适的配方。启动培养基为Ms+0.5mg·L-16-BA+0.01mg·L-1NAA。继代培养基MS+O.75mg·L-1。6-BA+0.01mg·L。NAA,可获得较高的增殖率。不定根最适诱导培养基为1/2MS+O.15mg·L—IBA,生根率达87%以上,组培苗移栽成活率达98%。  相似文献   
134.
Graphics processing unit (GPU) is becoming a powerful computational tool in science and engineering. In this paper, different from previous molecular dynamics (MD) simulation with pair potentials and many-body potentials, two MD simulation algorithms implemented on a single GPU are presented to describe a special category of many-body potentials – bond order potentials used frequently in solid covalent materials, such as the Tersoff potentials for silicon crystals. The simulation results reveal that the performance of GPU implementations is apparently superior to their CPU counterpart. Furthermore, the proposed algorithms are generalised, transferable and scalable, and can be extended to the simulations with general many-body interactions such as Stillinger–Weber potential and so on.  相似文献   
135.
136.
Previous studies proved that bone marrow‐derived mesenchymal stem cells (BMSCs) could improve a variety of immune‐mediated disease by its immunomodulatory properties. In this study, we investigated the effect on airway remodeling and airway inflammation by administrating BMSCs in chronic asthmatic mice. Forty‐eight female BALB/c mice were randomly distributed into PBS group, BMSCs treatment group, BMSCs control group, and asthmatic group. The levels of cytokine and immunoglobulin in serum and bronchoalveolar lavage fluid were detected by enzyme‐linked immunosorbent assay. The number of CD4+CD25+regulatory T cells and morphometric analysis was determined by flow cytometry, hematoxylin‐eosin, immunofluorescence staining, periodic‐acid Schiff, and masson staining, respectively. We found that airway remodeling and airway inflammation were evident in asthmatic mice. Moreover, low level of IL‐12 and high levels of IL‐13, IL‐4, OVA‐specific IgG1, IgE, and IgG2a and the fewer number of CD4+CD25+regulatory T cells were present in asthmatic group. However, transplantation of BMSCs significantly decreased airway inflammation and airway remodeling and level of IL‐4, OVA‐specific IgE, and OVA‐specific IgG1, but elevated level of IL‐12 and the number of CD4 + CD25 + regulatory T cells in asthma (P < 0.05). However, BMSCs did not contribute to lung regeneration and had no significant effect on levels of IL‐10, IFN‐Y, and IL‐13. In our study, BMSCs engraftment prohibited airway inflammation and airway remodeling in chronic asthmatic group. The beneficial effect of BMSCs might involved the modulation imbalance cytokine toward a new balance Th1–Th2 profiles and up‐regulation of protective CD4 + CD25 + regulatory T cells in asthma, but not contribution to lung regeneration. J. Cell. Biochem. 114: 1595–1605, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
137.
The relationships of extant and extinct lineages of Adephaga were analysed formally for the first time. Emphasis is placed on the aquatic and semiaquatic groups and their evolution in the Mesozoic. ?Triadogyrus and ?Mesodineutus belong to Gyrinidae, the sister group of the remaining families. ?Triaplidae are the sister group of the following groups (Haliplidae, Geadephaga, Dytiscoidea incl. ?Liadytidae, ?Parahygrobiidae and ?Coptoclavidae [major part]). The lack of a ventral procoxal joint and a very short prosternal process are plesiomorphies of ?Triaplidae. ?Coptoclavidae and ?Timarchopsinae are paraphyletic. ?Timarchopsis is placed in a geadephagan clade. In contrast to other coptoclavids, its metathorax is close to the condition found in Haliplidae, with a complete transverse ridge and coxae with large plates and free mesal walls. ?Coptoclavidae s.str., i.e. excl. ?Timarchopsis, is a dytiscoid subgroup. The mesal metacoxal walls are fused, the coxal plates are reduced, and the transverse ridge is absent. ?Stygeonectes belongs to this dytiscoid coptoclavid unit and is therefore misplaced in ?Timarchopsinae. ?Liadytidae belongs to a dytiscoid subgroup, which also comprises the extant families Aspidytidae, Amphizoidae, Hygrobiidae and Dytiscidae. ?Parahygrobia is the sister group of Hygrobiidae. The larvae are characterized by a broad gula, the absence of the lacinia, retractile maxillary bases and very long urogomphi set with long setae. ?Liadytiscinae is the sister group of extant Dytiscidae. There is no support for a clade ?Eodromeinae and for Trachypachidae incl. ?Eodromeinae. ?Fortiseode is nested within Carabidae. The exclusion of fossil taxa has no effect on the branching pattern. The evolution of Adephaga in the Mesozoic is discussed. Possible reasons for the extinction of ?Coptoclavidae are the rise of teleost fish and the competition of Gyrinidae and Dytiscidae, which possess efficient defensive glands and larval mandibular sucking channels.  相似文献   
138.
The results of the works on the international project for the Baltic sturgeon restoration in the basin of the Neman River are considered. The mutual goal of the project is the restoration of the Baltic sturgeon population in its whole former area in the Baltic Sea. Successful works on the restoration of the Baltic sturgeon population are conducted in the Oder and the Vistula basins. The stockings of the Neman River with the sturgeon fry were started from 2012 year. It is contemplated that the sturgeon stockings of the main rivers of the Baltic Sea will enable to restore local sturgeon populations in these river basins. Till the beginning of the XXI century it was supposed that the Atlantic sturgeon Acipenser sturio had inhabited the Baltic Sea, but numerous genetic analysis of the samples of the sturgeon bones from the archeological finds in the museums showed that the Baltic Sea had been inhabited with Acipenser oxyrhynchus and its population still inhabits several rivers in Canada. This discovery permitted to start the creation of the Baltic sturgeon broodstock. Sturgeon fry from the eggs imported from Canada were used for stocking at the first stage of the project. Later it is contemplated to use the fry from the broodstocks in Germany and Poland. Sturgeon fry hatched from Canadian eggs in Poland and reared in Lithuania was used for the Neman River stocking. The fry were tagged and released in the Neris and the Sventoji Rivers in the Neman River basin. The sturgeon migrated into the Curonian lagoon where the monitoring of the catches was fulfilled. The results of sturgeon catches monitoring are discussed.  相似文献   
139.
Loss of DBC2 (deleted in breast cancer 2) gene expression is frequent in breast cancer tissues. This can be explained by homozygous deletions or other mutations in a minority of cases but alternative mechanisms need to be investigated. Here, DBC2 expression was significantly suppressed compared with normal breast tissues in breast cancer tissues when analyzed by RT-PCR. Furthermore, DNA methylation on DBC2 was more prevalent in breast tumors than in normal tissues. DBC2 mRNA levels correlated with the degree of DBC2 methylation in breast cancer tissues and in a breast cancer cell line (T47D). Clinico-pathological correlation analysis showed that DBC2 promoter methylation was associated with tumor-node-metastasis stages II and III/IV, lymph node metastasis, p53 mutation, and HER2-positive status. Thus loss of DBC2 expression is caused by abnormal methylation of DBC2 and might have a role in breast cancer development.  相似文献   
140.
Diabetes results in several metabolic changes, including alterations in the transport, distribution, excretion, and accumulation of metals. While changes have been examined in several rat models of insulin resistance and diabetes, the metal ion concentrations in the tissues of Zucker lean, Zucker obese (an insulin resistance and early stage diabetes model), and Zucker diabetic fatty (ZDF, a type 2 diabetes model) have not previously been examined in detail. The concentration of Cu, Zn, Fe, Mg, and Ca were examined in the liver, kidney, heart and spleen, and Cr concentration in the liver and kidney of these rats were examined. Zucker obese rats have a reduction in the concentration of Cu, Zn, Fe, Mg in the liver compared to ZDF and/or lean Zucker rats, presumably as a result of the increased fat content of the liver of the obese rats. ZDF rats have increased concentrations of kidney Cu compared to the lean rats, while kidney Ca concentrations are increased in the Zucker obese rats. Spleen Fe concentrations are decreased in Zucker obese rats compared to the lean rats. No effects on metal concentrations in the heart were observed between the lean, obese, and ZDF rats, and no effects on Cr concentrations were identified. Cr(III) complexes have previously been shown to have beneficial effects on the signs of insulin resistance in Zucker obese and ZDF rats. The effects of daily gavage administration of chromium picolinate ([Cr(pic)3]) (1 mg?Cr/kg body mass), CrCl3 (1 mg?Cr/kg body mass), and Cr3 ([Cr3O(propionate)6(H2O)3]+) (33 μg and 1 mg?Cr/kg body mass) on metal concentrations in these tissues were examined. Treatment with CrCl3 and Cr3, but not [Cr(pic)3], at 1 mg?Cr/kg resulted in a statistically significant accumulation of Cr in the kidney of lean and obese but not ZDF rats but resulted in lowering the elevated levels of kidney Cu in ZDF rats, suggesting a beneficial effect on this symptom of type 2 diabetes.  相似文献   
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