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141.
Dae Won Chung Ki-Yeon Yoo In Koo Hwang Dae Won Kim Jin Young Chung Choong Hyun Lee Jung Hoon Choi Soo Young Choi Hwa Young Youn In Se Lee Moo-Ho Won 《Cellular and molecular neurobiology》2010,30(4):531-541
In this study, we observed the effects of lipopolysaccharide (LPS) on neurodegeneration and immune response in the hippocampus. LPS is a gram-negative bacterial cell surface proteoglycan and known as a bacterial endotoxin. For this, we investigated the optimal concentration of LPS influencing the ICR mouse hippocampus to measure the LPS receptor, e.g., toll-like receptor 4 (TLR4), expression in mouse hippocampal homogenates. TLR4 expression was significantly and prominently increased in the hippocampal homogenates of the LPS (1 mg/kg)-treated group. Next, we examined pro-inflammatory response in the hippocampus using cyclooxygenase-2 (COX-2, a marker for inflammatory response) immunohistochemistry after LPS treatment. COX-2 immunoreactivity was significantly increased in the endothelium of blood vessels in the hippocampus 6 h after LPS treatment, judging from double immunofluorescence study with platelet-derived endothelial cell adhesion molecule-1 (PECAM-1, a marker for endothelial cells): it decreased 12 h and disappeared 24 h after LPS treatment. In addition, the ionized calcium-binding adapter molecule 1 (Iba-1)-immunoreactive (+) microglia were morphologically activated in the mouse hippocampus after LPS treatment. At 24 h after LPS treatment, Iba-1+ microglia of activated forms were abundant in the hippocampus. However, NeuN (a neuron-specific soluble nuclear antigen)+ neurons were not significantly changed in the hippocampus after LPS treatment. Fluoro-jade B (a marker for neuronal degeneration)+ cells were not detected in the hippocampus at any time after LPS treatment. In addition, there were no significant differences in permeability of blood–brain barriers at any time points after LPS treatment. In brief, our results indicate that intraperitoneal administration of 1 mg/kg LPS effectively induces LPS receptor (TLR4) expression in the hippocampus, and the treatment increases corticosterone levels, inflammation in the blood vessels, and microglial activation in the hippocampus without any neuronal damage. 相似文献
142.
143.
SJ Park DH Kim MY Jung SJ Kim H Kim YH Kim JC Chae SK Rhee 《Journal of microbiology (Seoul, Korea)》2012,50(4):684-688
Glass slide arrayed with fosmid clone DNAs generated from swine feces as probes were fabricated and used as a metagenome microarray (MGA). MGA appeared to be specific to their corresponding target genomic fragments. The detection limit was 10 ng of genomic DNA (ca. 10(6) bacterial cells) in the presence of 1000 ng of background DNA. Linear relationships between the signal intensity and the target DNA (20-100 ng) were observed (r ( 2 )=0.98). Application of MGA to the comparison of swine fecal metagenomes suggested that the microbial community composition of swine intestine could be dependent on the health state of swine. 相似文献
144.
Muramoto Y Ozaki H Takada A Park CH Sunden Y Umemura T Kawaoka Y Matsuda H Kida H 《Microbiology and immunology》2006,50(1):73-81
Severe hemorrhage at multiple organs is frequently observed in chickens infected with highly pathogenic avian influenza (HPAI) A viruses. In this study we examined whether HPAI virus infection leads to coagulation disorder in chickens. Pathological examinations showed that the fibrin thrombi were formed in arterioles at the lung, associated with the viral antigens in endothelial cells of chickens infected intravenously with HPAI virus. Hematological analyses of peripheral blood collected from the chickens revealed that coagulopathy was initiated at early stage of infection when viral antigens were detected only in the endothelial cells and monocytes/macrophages. Furthermore, gene expression of the tissue factor, the main initiator of blood coagulation, was upregulated in the spleen, lung, and brain of HPAI virus-infected chickens. These results suggest that dysfunction of endothelial cells and monocytes/macrophages upon HPAI virus infection may induce hemostasis abnormalities represented by the excessive blood coagulation and consumptive coagulopathy in chickens. 相似文献
145.
Regenerative ability of somatic single and multiple embryos from cotyledons of Korean ginseng on hormone-free medium 总被引:4,自引:0,他引:4
Cotyledon explants of Korean ginseng (Panax ginseng C. A. Meyer) produced somatic embryos directly on growth regulator-free medium. Somatic embryos developed as either multiple
or single-state forms, depending on the degree of maturity of the cotyledons. Cotyledon explants from midmature zygotic embryos
formed multiple embryos, while cotyledons from fully mature zygotic embryos formed single embryos. Somatic single embryos
regenerated into normal plantlets with both roots and shoots, while multiple embryos did not produce roots but regenerated
only into multiple shoots. In full-strength MS basal medium, the root growth of plantlets derived from single embryos was
weak compared to that of shoots. Deletion of ammonium nitrate from the MS medium promoted the root growth of the plantlets.
The ginseng plants with well-developed shoots and roots regenerated from single embryos were successfully acclimatized in
a greenhouse when they were planted in soil.
Received: 19 July 1997 / Revision received: 6 October 1997 / Accepted: 3 October 1997 相似文献
146.
A new biosensor for specific determination of sucrose was developed using an oxidoreductase of Zymomonas mobilis and invertase. Cells of Z. mobilis were permeabilized with toluene in order to utilize the enzymes of glucose-fructose oxidoreductase and gluconolactonase inside the intact cells. Permeabilized cells and invertase were coimmobilized in a gelatin membrane, and a whole cell enzyme electrode was constructed by fixing the membrane on a pH electrode. The production of hydrogen ion was detected using the biosensor-connected microcomputer, and the concentration of sucrose was determined by using both the initial rate and the steady-state methods. Optimum conditions for biosensor response were pH 6.2 and temperature 35 degrees C. The effect of interfering compounds on the electrode response was investigated, and the interference by various sugars was eliminated by determining sucrose concentration using the steady-state method. The biosensor developed is simple and reproducible, and the calibration curve for sucrose is linear up to 70 g/L. 相似文献
147.
Leem JY Park DS Suh EY Hur JH Oh HW Park HY 《Archives of insect biochemistry and physiology》2007,66(4):204-213
A new antimicrobial peptide, cryptonin, was isolated and characterized from the adult Korean blackish cicada, Cryptotympana dubia. It consists of 24 amino acid residues and has a molecular weight of 2,704 Da on mass spectroscopy. The predicted alpha-helical structure analysis and increased helix percent in 40% trifloroethanol of cryptonin suggests that it belongs to the typical linear alpha-helix forming peptide. Binding of the biotin-labeled cryptonin at the surface of E. coli cells and increased influx of propidium iodide in E. coli after cryptonin treatment indicates that it kills microbial cells by binding bacterial cell surfaces and disrupting the cell permeability. Cryptonin showed strong antibacterial (MIC 1.56-25 microg/ml) and antifungal (MIC 3.12-50 microg/ml) activities against tested bacteria and fungi including two antibiotic-resistant bacterial strains; methicilin-resistant S. aureus and vancomycin-resistant Enterococci (MIC 25 microg/ml, each). 相似文献
148.
An olfactory receptor protein of C. elegans, ODR-10, was expressed in Escherichia coli as a fusion protein, with GST and 6x His-tag. The expression of the target protein was analyzed by SDS-PAGE and Western blot, and was confirmed to be expressed at the membrane fraction of the host E. coli. The surface of a quartz crystal microbalance (QCM) was coated with crude membrane extracts, containing the expressed receptor protein, and the interaction between the olfactory receptor and various odorant molecules examined. Compared with other odorants, diacetyl (2,3-butanedione), known as a natural ligand for the ODR-10 receptor, interacted most strongly with the expressed protein. Various concentrations of diacetyl were applied to the expressed ODR-10 receptor, and the response of the QCM showed a linear relationship to the logarithmic value of the odorant concentration. This piezoelectric biosensor system, using olfactory receptor proteins expressed in E. coli, can be used in diagnostics, toxic chemical detection and the quality control of food. 相似文献
149.
150.
OBJECTIVE: To evaluate the accuracy of fine needle aspiration cytology (FNAC) of the breast at our institution and to perform quality assurance. STUDY DESIGN: Two hundred forty-six cases with pathologic confirmation were selected and reviewed. A pathologist performed most of the aspirations at an outpatient breast clinic. We correlated cytologic and histologic findings and evaluated the influence of the size, location, grade, and pathologic subtypes and fibrosis in breast lesions on diagnostic results. RESULTS: The likelihood ratios for malignant, suspicious, atypical, benign and unsatisfactory cytologic diagnoses were 98.71, 5.48, 1.09, 0.07 and 0.55, respectively. The absolute and complete sensitivities for malignant lesions were 64.5% and 90.3%, respectively. The specificity was 71.9%. False negative and positive rates were 4.3% and 0.7%, respectively. The predictive value for a malignant cytologic diagnosis was 98.4%. The rate of unsatisfactory samples was 9.3%. The rate of concordance between cytologic and histologic diagnosis was lower for large and diffusely growing lesions (benign and malignant), for malignancies with abundant fibrosis and of unusual types and for carcinomas of low grade. All axillary and recurrent chest wall lesions were diagnosed cytologically. Cell block sections were useful in a small number of cases. CONCLUSION: Understanding the performance and limitations of FNAC can enhance its value as a diagnostic technique in the management of breast disease. 相似文献