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31.
Bernhard J. Connemann Heidrun Busche Jürgen Kreusch Helmut H. Wolff 《Skin research and technology》1996,2(1):40-48
Background/aims: Quantitative measurement of skin roughness has proved to be a valuable tool in the efficacy-control of external applications, but it suffers from not yielding easily comparable results. The most important sources of inter-observer variability are high-pass filters used to separate roughness and waviness, and low-pass filters which result from the finite resolution of the instrument or from the finite sampling interval of digital measurement. In the present study, the effects of high-pass filters and sampling intervals on the roughness measured were investigated. Methods: Dynamically focusing optical profilometry was used to measure the surfaces of negative replicas of healthy human skin. High-pass cut-off wavelengths and sampling intervals were varied systematically. Results/conclusions: Virtually unbiased estimates for the roughness parameters K, Sk, Rq, and Ra can be obtained using sampling intervals of 40 or even 80 μm. Regarding these roughness parameters, it is far better to do more scans than to shorten the sampling interval. The roughness parameters Rz, Rp, Rt, Rpm, Rmax, Pt, on the other hand are very sensitive to the influence of the sampling interval; to achieve satisfying estimates, the sampling interval should be no longer than 2 to 5 urn; as an important parameter’of the measurement, it is worthy of remark and should always be indicated. The way the mean square roughness Rq depends on the cut-off wavelength is not well described by the Sayles-Thomas-relation Rq~λc0.5. If the power-spectrum |h*(v)|2 approximates sufficiently to a power law, |h*(v)|2~vδ, a better estimate is given by Rq~λcγ with γ=-(δ+1)/2. In many cases, γ=1 or Rq~λc will suffice. 相似文献
32.
33.
Sylvia Czapla Ralf Ruhmann Joachim Rübner Veit Zschuppe Dietmar Wolff 《Macromolecular chemistry and physics.》1993,194(1):243-250
The synthesis and characterization of new poly({6-[4-(4-cyanophenylcarbamoyl)phenoxy]hexyl methacrylate}-co-{6-[4-(4- cyanophenylazo)phenoxy]hexyl methacrylate}) are reported. Their liquid-crystalline properties are investigated using differential scanning calorimetry, polarizing microscopy and X-ray diffraction techniques. The glass transition temperatures and the clearing points can be influenced by variation of the copolymer composition. The substances offer a relatively broad temperature range of mesomorphic properties suitable for photochemical studies. 相似文献
34.
Amyloidosis and the serum amyloid A protein response to muramyl dipeptide analogs and different mycobacterial species. 总被引:1,自引:1,他引:1 下载免费PDF全文
K P McAdam N T Foss C Garcia R DeLellis L Chedid R J Rees S M Wolff 《Infection and immunity》1983,39(3):1147-1154
Serum amyloid A protein (SAA) elevation accompanies induction of secondary amyloidosis in mice given Mycobacterium butyricum in Freund adjuvant. The synthesis of SAA by cultured hepatocytes is induced by a macrophage-derived mediator, which has been identified as interleukin 1. In these studies, SAA synthesis has been used as an index of macrophage activation to examine the in vivo response of mice to challenge with seven different mycobacteria and with synthetic analogs of the immunoadjuvant N-acetylmuramyl-L-alanyl-D-isoglutamine [MDP(L-D)]. SAA synthesis was stimulated by administration (by the intraperitoneal route) of the mycobacteria dissolved in saline, with Mycobacterium vaccae being the most active and Mycobacterium leprae being the least stimulatory. MDP(L-D), which is the minimal structure (molecular weight, 492) able to substitute for mycobacteria in Freund adjuvant, stimulated SAA synthesis, whereas the MDP(D-D) isomer was inactive. The butyl ester of MDP, which induces no detectable pyrogenicity but retains adjuvanticity, required a 100-fold greater dosage than MDP(L-D) in stimulating SAA synthesis. Amyloidosis was detected histologically only when active SAA inducers MDP(L-D), M. vaccae, and M. butyricum, were administered in incomplete Freund adjuvant, with amyloid-enhancing factor. These studies demonstrated that SAA elevation was a sensitive in vivo marker of the capacity of antigens to stimulate macrophages to produce interleukin 1. A point of considerable relevance to the human use of MDP was the observation that repeated injections of the adjuvant MDP in saline did not induce secondary amyloidosis. 相似文献
35.
Wolff N Yannai S Karin N Levy Y Reifen R Dalal I Cogan U 《The Journal of allergy and clinical immunology》2004,114(5):1151-1158
BACKGROUND: The increased consumption of foods containing sesame seeds is paralleled by an increase in reported sesame-induced allergic reactions. OBJECTIVE: This study aimed at identifying and characterizing the linear B-cell epitopes of the 14-kd beta-globulin, the major allergen of sesame seed. METHODS: A peptide containing 71 amino acids (peptide B) was previously identified by us as the IgE-binding region on beta-globulin. To determine the amino acid sequence of the IgE-binding sites on peptide B, we synthesized overlapping peptides 20 and 10 amino acid residues long that span the entire length of peptide B, which were offset from each other by 10 and 2 amino acid residues, respectively. Sera from 20 subjects given diagnoses of allergy to sesame beta-globulin served to identify the epitopes by using the dot-blot test. RESULTS: At least 9 different IgE-recognition sites were identified on peptide B. Three of them, numbers 2, 3, and 13 (corresponding to amino acids 46-55, 48-57, and 76-86, respectively, in the beta-globulin sequence), appeared to be immunodominant IgE-binding epitopes. Also, these peptides were best recognized in terms of intensity of response. There was no obvious sequence motif shared by the 9 different IgE-binding epitopes of beta-globulin. However, approximately 60% of the amino acids represented in the epitopes are hydrophobic residues. CONCLUSION: Identification of the IgE-binding epitopes might provide a better understanding of the functional role the allergens play in the disease and might have implications for immunodiagnosis and probably immunotherapy. 相似文献
36.
37.
Kh. R. Koczorek H. P. Wolff Marie-Luise Beer 《Journal of molecular medicine (Berlin, Germany)》1957,35(10):497-502
Ohne ZusammenfassungMit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
38.
W. Prohaska C. Wolff E. Lechler K. Kleesiek 《Journal of molecular medicine (Berlin, Germany)》1991,69(7):294-296
Summary Anti-hepatitis C virus antibody screening of blood donors in different countries revealed prevalences ranging from 0,4–1,4%. These results were obtained with an enzyme immunoassay based on a recombinant hepatitis C virus antigen. We applied a specific inhibition assay (neutralization assay) and a recombinant immunoblot assay to determine the specificity of positive reactions in the enzyme immunoassay.Of 2836 blood donor sera tested, 10 (0,35%) were reactive in the enzyme immunoassay, however, only 3 sera (0,1%) proved to be specifically anti-HCV positive in the inhibition assay. The recombinant immunoblot assay gave similar results. The prevalence of anti-hepatitis C virus antibodies among blood donors has been overestimated in recent publications. Furthermore the high rate of false positives in the enzyme immunoassay may explain reports claiming that only a minor part of EIA positive blood units transmitted the hepatitis C virus to recipients.The inhibition assay was also applied to sera of haemophiliacs and of patients with hepatopathy which had reacted positively in the anti-hepatitis C virus antibody enzyme immunoassay. The antihepatitis C virus specificity was confirmed for all sera from the haemophiliacs group (100%) and for 77% of the hepatopathy patients group. Thus, the anti-hepatitis C virus enzyme immunoassay has a high predictive value when it is used to screen groups with high risks of parenteral hepatitis C virus infection, however, its predictive value is very low when it is used for blood donor screening.Abbreviations EIA
enzyme immunoassay
- HCV
hepatitis C virus
- RIBA
recombinant immunoblot assay
- SOD
superoxide dismutase 相似文献
39.
Local gamma-aminobutyric acid (GABA) application into the intact superior cervical ganglion (SCG) of the adult rat allows active innervation of a surgically implanted hypoglossal nerve in addition to the normal nerve supply of the ganglion. In GABA-treated SCG of the adult rat, action potentials could be obtained on stimulation of both the preganglionic nerve trunk and the implanted hypoglossal nerve. Both action potentials were reversibly sensitive to hexamethonium bromide indicating new cholinergic synapses established between axons in the hypoglossal nerve and principal sympathetic neurons. If GABA treatment of the ganglion was omitted, the double innervation did not develop after hypoglossal nerve implantation. 相似文献
40.
Myosin VIIA gene: heterogeneity of the mutations responsible for Usher syndrome type IB 总被引:8,自引:1,他引:8
Levy G; Levi-Acobas F; Blanchard S; Gerber S; Larget-Piet D; Chenal V; Liu XZ; Newton V; Steel KP; Brown SD; Munnich A; Kaplan J; Petit C; Weil D 《Human molecular genetics》1997,6(1):111-116
Usher syndrome is recognized as the most frequent cause of hereditary
deaf-blindness. Usher syndrome type I (USH1), the most severe form of the
disease, is characterized by profound congenital sensorineural deafness,
constant vestibular dysfunction, and retinitis pigmentosa of prepubertal
onset. This form is genetically heterogeneous and five loci (USH1A-E) have
been mapped thusfar. However, only the gene responsible for USH1 B (which
accounts for approximately 75% of USH1 cases) has been characterized. It
encodes a long-tailed unconventional myosin, myosin VIIA, with a predicted
2215 amino acid sequence. Primers covering the complete myosin VIIA coding
sequence as well as the 3' non coding sequence were designed, allowing
direct sequence analysis of each of the 48 coding exons and flanking splice
sites in seven patients affected by USH1. Four novel mutations were thereby
identified. The possibility should now be considered of a sequence-based
prenatal diagnosis in some of the families affected by this very severe
form of Usher syndrome.
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