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61.
62.
Cryopreserved human haematopoietic stem cells retain engraftment potential after extended (5-14 years) cryostorage 总被引:3,自引:0,他引:3
Harvesting of stem cells during the early phases of treatment with no immediate intention to perform a stem cell transplant is becoming an increasingly common practice. Such "insurance" harvests are often stored for many years before being needed for transplant in a subsequent relapse. The effect of long-term cryostorage (5-14 years) on the viability and functional capacity of haematopoietic stem cells (HSCs) was investigated in 40 bone marrow and peripheral blood harvests using standard in vitro methods, the colony forming unit-granulocyte/macrophage (CFU-GM) assay and a single platform viable CD34(+) cell absolute count by flow cytometry. Forty percent of harvests had CD34(+) HSC counts of at least 0.7 x 10(6)/kg bodyweight and 85% had CFU-GM counts of at least 1.0 x 10(5)/kg bodyweight, these values representing our institutional minimum requirements for safe transplantation. Based on these results, it appears that HSC collections can remain adequate for safe transplantation after up to 14 years of cryostorage. However, as deterioration of HSC quality and viability may occur, some precautions may be warranted, namely harvesting higher than normal numbers of HSCs in collections intended for long-term storage and repeating in vitro assays on harvests after long-term storage prior to transplantation. 相似文献
63.
Some 2-amino-4,6-diarylpyrimidines 2 have been prepared from substituted benzylideneacetophenones and guanidine hydrochloride in the presence of alkali by conventional heating in alcoholic medium and microwave heating in solvent-free conditions. N-(2,3,4,6-Tetra-O-acetyl-β-d-glucopyranosyl)-N′-(4′,6′-diarylpyrimidin-2′-yl)thioureas 4 have been synthesized by reaction of per-O-acetylated glucopyranosyl isothiocyanate 1 and substituted 2-amino-4,6-diarylpyrimidines 2. Two different methods have been used, namely, refluxing in anhydrous dioxane and solvent-free microwave-assisted coupling. The second procedure afforded higher yields in much shorter reaction times. The compounds 2 and 4 were tested for their antibacterial and antifungal activities in vitro against Staphylococcus epidermidis, Enterobacter aerogenes and Candida albicans by disc diffusion method. 相似文献
64.
Elisabeth Ekener-Petersen Göran Finnveden 《The International Journal of Life Cycle Assessment》2013,18(1):127-143
Purpose
A generic hotspot assessment of social impacts from a product was conducted, using a laptop computer as a case. The aims of the case study were to identify social hotspots of the laptop and to test and evaluate the methodology.Methods
The case study was based on the social LCA methodology described in the Guidelines for social LCA and included the product system from ‘cradle to grave’ as well as the impacts on all relevant stakeholders. We focused on a simplified list of materials and used mainly country-specific data.Results and discussion
A new method for impact assessment of hotspots was developed. The total activity in each phase was distributed among countries. The countries were divided into groups related to the extent of activity in the product system, as well as to their performance on a subcategory. High values in both groups were highlighted and hotspots were identified. The results revealed some hotspots, some hot countries and some hot issues, all indicating a risk of negative social impacts in the product system of a laptop. It also identified workers and the local community as the stakeholders most at risk of negative social impacts. Among the hotspots identified, the following subcategories were of importance: safe and healthy living conditions, social benefit/social security, access to material resources, involvement in areas with armed conflicts, community engagement (lack of), corruption, and access to immaterial resources.Conclusions
The study showed it is possible to conduct a social LCA on a generic complex product using the Guidelines, even though data collection was impaired by lack of data and low data quality. It identified methodological issues that need further attention, for example the indicator impact pathways. Still, it is clear that new insights can be gained by social LCA, where the life cycle perspective and the systematic approach help users identify potentially important aspects that could otherwise have been neglected. 相似文献65.
Colitis induced by proteinase-activated receptor-2 agonists is mediated by a neurogenic mechanism 总被引:6,自引:0,他引:6
Nguyen C Coelho AM Grady E Compton SJ Wallace JL Hollenberg MD Cenac N Garcia-Villar R Bueno L Steinhoff M Bunnett NW Vergnolle N 《Canadian journal of physiology and pharmacology》2003,81(9):920-927
Proteinase-activated receptor-2 (PAR2) activation induces colonic inflammation by an unknown mechanism. We hypothesized that PAR2 agonists administered intracolonically in mice induce inflammation via a neurogenic mechanism. Pretreatment of mice with neurokinin-1 and calcitonin-gene-related peptide (CGRP) receptor antagonists or with capsaicin showed attenuated PAR2-agonist-induced colitis. Immunohistochemistry demonstrated a differential expression of a marker for the type-1 CGRP receptor during the time course of PAR2-agonist-induced colitis, further suggesting a role for CGRP. We conclude that PAR2-agonist-induced intestinal inflammation involves the release of neuropeptides, which by acting on their receptors cause inflammation. These results implicate PAR2 as an important mediator of intestinal neurogenic inflammation. 相似文献
66.
M. V. Bilenko Yu. A. Vladimirov S. A. Pavlova Nguyen Thi Thu Thuy Tran Thi Hai Yen 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2009,3(1):64-70
Production of reactive oxygen species (ROS) by macrophages derived from blood monocytes of healthy donors (MPN) and patients with ischemic heart disease (IHD) (MPIHD) before, during, and after their incubation with low-density lipoprotein (LDL) isolated from blood plasma of healthy donors (LDLN) and patients with a high cholesterol level (LDLH) was investigated by the method of luminol-dependent (spontaneous) and stimulated chemiluminescence (CL) using opsonized zymosan (OZ) or phorbol-12-myristate-13-acetate (PMA) as the CL stimulators. It was shown that proper, luminol-dependent, and zymosan-or PMA-stimulated chemiluminescence of MPIHD was 1.4-, 1.8-, 2.7-, and 1.6-fold higher than the same types of chemiluminescence of MPN, respectively, (p<0.05–0.01). Although the effect of OZ on MPN and MPIHD was more potent than that of PMA (by 4.3- and 3.2-fold, respectively), but it appeared in 2.5–3.0 times slower than that of PMA. LDLN and LDLH incubated with MPN for the first 15 and 60 min caused the 1.4- and 2.5-increase of the luminol-dependent CL of MPN; the same treatment of MPIHD did not influence ROS production by these cells. Repeated increase in the OZ-stimulated CL of MPN was also observed after preincubation for 15–180 min with LDLN and LDLH followed by LDL removal, subsequent MPN washing and addition of Hanks solution and OZ; the repeated increase in OZ-stimulated CL of MPN was only observed after incubation with LDLH than with LDLN. No increase of CL was observed in experiments with MPIHD. Thus, more intensive chemiluminescence of macrophages obtained from blood of patients with IHD suggests their in vivo stimulation. LDLN and LDLH may cause both primary and secondary (after preincubation) stimulating effect on CL of MPN but not of MPIHD. Thus, the analysis of macrophage chemiluminescence is a sensitive test for evaluation the degree of macrophage stimulation; it may be effectively used for monitoring of effectiveness of medical treatment of patients. 相似文献
67.
68.
Lundin KE Ge R Svahn MG Törnquist E Leijon M Brandén LJ Smith CI 《Biomolecular engineering》2004,21(2):51-59
Peptide nucleic acid (PNA) is a DNA analog with broad biotechnical applications, and possibly also treatment applications. Its suggested uses include that of a specific anchor sequence for biologically active peptides to plasmids in a sequence-specific manner. Such complexes, referred to as Bioplex, have already been used to enhance non-viral gene transfer in vitro. To investigate how hybridization of PNAs to supercoiled plasmids would be affected by the binding of multiple PNA-peptides to the same strand of DNA, we have developed a method of quantifying the specific binding of PNA using a PNA labeled with a derivative of the fluorophore thiazole orange (TO). Cooperative effects were found at a distance of up to three bases. With a peptide present at the end of one of the PNAs, steric hindrance occurred, reducing the increase in binding rate when the distance between the two sites was less than two bases. In addition, we found increased binding kinetics when two PNAs binding to overlapping sites on opposite DNA strands were used, without the use of chemically modified bases in the PNAs. 相似文献
69.
70.
Xing C Sestak AL Kelly JA Nguyen KL Bruner GR Harley JB Gray-McGuire C 《Human genetics》2007,120(5):623-631
Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by both population and phenotypic heterogeneity.
Our group previously identified linkage to SLE at 4p16 in European Americans (EA). In the present study we replicate this
linkage effect in a new cohort of 76 EA families multiplex for SLE by model-free linkage analysis. Using densely spaced microsatellite
markers in the linkage region, we have localized the potential SLE susceptibility gene(s) to be telomeric to the marker D4S2928
by haplotype construction. In addition, marker D4S394 showed marginal evidence of linkage disequilibrium with the putative
disease locus by the transmission disequilibrium test and significant evidence of association using a family-based association
approach as implemented in the program ASSOC. We also performed both two-point and multipoint model-based analyses to characterize
the genetic model of the potential SLE susceptibility gene(s), and the lod scores both maximized under a recessive model with
penetrances of 0.8. Finally, we performed a genome-wide scan of the total 153 EA pedigrees and evaluated the possibility of
interaction between linkage signals at 4p16 and other regions in the genome. Fourteen regions on 11 chromosomes (1q24, 1q42,
2p11, 2q32, 3p14.2, 4p16, 5p15, 7p21, 8p22, 10q22, 12p11, 12q24, 14q12, 19q13) showed evidence of linkage, among which, signals
at 2p11, 12q24 and 19q13 also showed evidence of interaction with that at 4p16. These results provide important additional
information about the SLE linkage effect at 4p16 and offer a unique approach to uncovering susceptibility loci involved in
complex human diseases. 相似文献