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81.
82.
Kawano Y Fukuda J Itoh H Takai N Nasu K Miyakawa I 《American journal of reproductive immunology (New York, N.Y. : 1989)》2004,52(2):124-128
PROBLEM: In order to investigate the role of macrophage colony-stimulating factor (M-CSF) and monocyte chemoattractant protein -1 (MCP-1) in human ovulation, we studied the regulation of M-CSF and MCP-1 in cultured human granulosa cells. METHOD OF STUDY: Immortalized granulosa cells (GC1a) were cultured in serum-free medium, and incubated with interleukin (IL)-1alpha, IL-1 receptor antagonist (ra) and tumor necrosis factor (TNF)-alpha. The supernatants were collected, and M-CSF and MCP-1 were measured by ELISA. RESULTS: The levels of M-CSF and MCP-1 were increased after treatment with IL-1alpha (1 nm) and TNF-alpha (1 nm) in a time-dependent manner. The levels of M-CSF and MCP-1 were significantly increased after treatment with IL-1alpha and TNF-alpha in a dose-dependent manner. However, the levels of M-CSF and MCP-1 were significantly decreased by treatment with IL-1alpha (1 nm) and/or increasing concentrations of IL-1 ra. CONCLUSIONS: Our data indicated that M-CSF and MCP-1 were regulated by IL-1alpha and TNF-alpha. It was suggested that M-CSF and MCP-1 may play an important role in human preovulatory processes. 相似文献
83.
Tsukamoto H Takei I Ishii K Fukada H Ohtake T Kikuchi H Hirose N Watanabe K 《Rinsho byori. The Japanese journal of clinical pathology》2005,53(9):818-824
In patients with Type 2 diabetes mellitus (Type 2 DM), the relationship between the prevalence rate of small dense LDL (sdLDL) and parameters of lipid metabolism was analyzed using the method devised by modified Krauss method using apoferritin as an internal standard. The prevalence rate of sdLDL was 34% compared with it of normal subjects in this study. When the severity of Type 2 DM was classified into three groups of the HbA1c value, neither the sdLDL size nor its prevalence rate differed significantly depending upon the severity of the Type 2 DM. Also, when the prevalence rate of sdLDL was analyzed in relation to the severity of complications, i.e., of microangiopathy (retinopathy and nephropathy) or macroangiopathy (cerebral infarction), there was no significant difference in the prevalence rate of sdLDL depending on the severity of any of these complications. On the other hand, the prevalence rate of sdLDL was found to be correlated with the serum TG level. The serum level of TG-rich remnants (metabolites of TG) was also high in patients with sdLDL. It should take notice that the assessment of sdLDL should be used the authorized method for the evaluation. Thus it is concluded that the levels of sdLDL were important in evaluation of Type 2 DM. The prevalence rate of sdLDL did not correlate with the severity, nor the modalities for the complications of Type 2 DM. 相似文献
84.
alpha 2-macroglobulin stimulation of protein tyrosine phosphorylation in macrophages via the mannose receptor for Fc gamma receptor-mediated phagocytosis activation. 总被引:2,自引:0,他引:2
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Macrophage phagocytic activity has previously been shown to be increased by binding of modified alpha 2-macroglobulin (alpha 2M) with mannose residues at termini of sugar chains to mannose receptors on macrophages, with a subsequent increase in the number of Fc gamma receptors at the cell surface. In the present study, an examination was made of the association of protein tyrosine kinase with the increase in number of Fc gamma receptors following binding of modified alpha 2M to mannose receptors. The phagocytosis of IgG-opsonized sheep red blood cells through the action of the Fc gamma receptor by modified alpha 2M was inhibited by mannose and herbimycin A and slightly so by genistein. The mannose receptor would thus appear to be associated with tyrosine kinase activity. By Western blotting, tyrosine phosphorylated proteins with molecular weights of 32000, 34000, 36000, 65000, 85000 and 110000 appeared or increased upon treating macrophages with modified alpha 2M. The degree of tyrosine phosphorylated proteins was the same for control macrophages following incubation in the presence of mannose and herbimycin A. Genistein treatment affected only tyrosine phosphorylated proteins of 65000 and 110000. The binding of modified alpha 2M to mannose receptors was demonstrated by the inducement of tyrosine kinase activation that was sensitive to herbimycin A, followed by an increase in Fc gamma receptors and consequently greater phagocytosis. 相似文献
85.
Shinkai T De Luca V Zai G Shaikh S Matsumoto C Arnold PD Hwang R King N Trakalo J Potapova N Wong G Hori H Wong AH Ohmori O Nakamura J Kennedy JL 《Psychiatric genetics》2004,14(3):177-180
OBJECTIVE: Oxidative stress such as free radical-mediated neuronal dysfunction may be involved in the pathophysiology of schizophrenia. The human glutathione peroxidase (GPX1) is a selenium-dependent enzyme, which plays an important role in the detoxification of free radicals. We therefore hypothesized that the GPX1 gene, which is located on chromosome 3p21.3, may be involved in the pathophysiology of schizophrenia. The aim of this study is to examine whether a potentially functional polymorphism, a proline (Pro) to leucine (Leu) substitution at codon 197 (Pro197Leu) of the human GPX1 gene, is associated with susceptibility to schizophrenia. METHODS: We genotyped the Pro197Leu polymorphism in a total of 113 nuclear families that had a proband with schizophrenia. Genetic association was tested using the transmission disequilibrium test (TDT), the sib transmission disequilibrium test (STDT), and the family-based association test (FBAT). RESULTS: The minor allele (Leu) frequency was calculated to be 0.282. We could not find significant transmission disequilibrium of the alleles for the Pro197Leu polymorphism in the GPX1 gene in association with the presence of schizophrenia in our family sample (TDT, chi2=0.03, degrees of freedom=1, P=0.86; combined TDT-STDT, Z'=-0.052, P=0.47; FBAT, Z=0.000, P=1.000). CONCLUSION: The results of this study suggest that the GPX1 polymorphism is unlikely to be associated with susceptibility to schizophrenia. 相似文献
86.
Antibody Response to Bacterial Antigens: Characteristics of Antibody Response to Somatic Antigens of Salmonella typhimurium
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The character of the antibody response in the rabbit to Salmonella typhimurium somatic (O) antigen was similar to the response to each of several serotypes of Shigella flexneri O antigens, namely a predominance of production of immunoglobulin M (IgM) antibody. Lipopolysaccharide protein (LPSP) and lipopolysaccharide (LPS) fractions of Salmonella O antigen differed significantly in both quantitative and qualitative aspects of their immunogenicity. LPSP elicited high levels of agglutinins and also induced the production of a significant amount of immunoglobulin G (IgG) antibody at a late period. LPS antigen elicited low levels of agglutinins which were exclusively IgM antibody. These results suggested that the chemical nature of the antigen is one important factor in the determination of the character of the antibody response. Further, it is suggested that the protein moiety of the O antigen complex is a carrier active in allowing induction of early IgM and of late IgG antibodies; in contrast, the lipid moiety may compete with this action of the carrier protein, thereby suppressing IgG antibody in the primary stage of the antibody-forming process. 相似文献
87.
The effects of different molecular weights of hyaluronic acid (HA), a major component of extracellular matrix, on gap junctional intercellular communication (GJIC) in normal human dermal fibroblasts (NHDF cells) were investigated. NHDF cells were cultured for 4 days with different molecular weights of HA and then the extent of GJIC was assessed by the scrape-loading dye transfer method, using Lucifer yellow. The area of dye transfer was greater in the dishes coated with HA than in those to which HA was added. Thus, NHDF cells cultured on surfaces coated with high molecular weight (HMW) HA (MW, 800 kDa) showed greatly enhanced GJIC. Furthermore, another aim of this study was to evaluate the effects of different molecular weights of HA on the production of FGF-2 and KGF, because both are important cytokines produced by NHDF cells. When FGF-2 and KGF cultured levels of cell extracts and media were determined by ELISA, both levels were significantly enhanced when cells were grown on plates coated with HMW HA. This finding indicated that the function of gap junction channels in NHDF cells grown on plates coated with HMW HA may promote the biosynthesis of growth factors such as FGF-2 and KGF. 相似文献
88.
Comparison of latex agglutination with enzyme immunoassay for detection of rotavirus in fecal specimens 总被引:2,自引:0,他引:2
Raboni SM Nogueira MB Hakim VM Torrecilha VT Lerner H Tsuchiya LR 《American journal of clinical pathology》2002,117(3):392-394
Human rotaviruses are the most important etiologic agents of acquired diarrhea in infants and young children worldwide. Early diagnosis is essentialfor effective patient treatment. The latex agglutination (LA) assays for rotavirus diagnosis are rapid, inexpensive, and the most widely used to screen specimens. The performance of the LA Rotagen (Biokit S.A., Barcelona, Spain) was evaluated for rotavirus detection infecal samples of outpatients with acute gastroenteritis. This assay was compared with the enzyme immunoassay (EIA) EIARA (Bio-Manguinhos, Rio de Janeiro, Brazil). From January to October 2000, 285 fecal specimens were analyzed. Forty-four samples (15.4%) were reactive, 214 (75.4%) were nonreactive, and 27 (9.5%) were indeterminate by LA. All LA-positive samples were positive by EIA, and 2 LA-negative samples were positive by EIA. Of specimens indeterminate by LA, 67% were positive by EIA. The sensitivity, specificity, and accuracy of LA were 69%, 100%, and 93%, respectively. These results indicate that assay is as sensitive and specific as the EIA, and it could be applied on a large scale for screening stool specimens in suspected rotavirus diarrhea. However, the indeterminate results must be confirmed by other methods, such as EIA. 相似文献
89.
Poly-L-lactic acid (PLLA) is a widely used promising material for surgical implants such as tissue-engineered scaffolds. In this study, we aimed to determine the in vivo effect of PLLA plates on the cellular function of subcutaneous tissue in the two mouse strains, BALB/cJ and SJL/J, higher and lower tumorigenic strains, respectively. Gap-junctional intercellular communication (GJIC) and the expression of connexin 43 (Cx43) protein were significantly suppressed, whereas the secretion of transforming growth factor-beta 1 (TGF-beta 1) level was significantly increased in PLLA-implanted BALB/cJ mice compared with BALB/cJ controls. However, no significant difference in TGF-beta 1 secretion was observed between the SJL/J-implanted and SJL/J control mice. We found for the first time that a significant difference was observed between the two strains; thus, the PLLA increased the secretion of TGF-beta 1 and suppressed the mRNA expression of Cx43 at the earlier stage after implantation into the higher-tumorigenic strain, BALB/cJ mice. This novel mechanism might have a vital role in the inhibition of GJIC and promote the tumorigenesis in BALB/cJ mice. 相似文献
90.
TCR repertoire in early fetal mouse thymus 总被引:1,自引:0,他引:1
Ohki-Hamazaki Hiroko; Makino Yasuhiko; Kanno Masamoto; Koseki Haruhiko; Akasaka Takeshi; Taniguchi Masaru 《International immunology》1995,7(3):493-499
We investigated the rearrangement and expression of TCR genesin mouse fetal thymus organ culture, a system that avoids subsequententry of hematopoietic precursor cells. The first observablerearranged TCR gene was homogeneous V2-J2, detectable as earlyas fetal day 11 (d11) in the thymic primordla. The productiveTCR was homogeneous V5-J1, first detectable in d13 thymocytes,followed by adult-type TCR (V4 and V7). Sequence analysis ofTCR revealed five types of V-J junctional sequences. In thevery early stage, a homogeneous V-J junction is generated viaa short homology sequence in the coding region (Type I), whilea short homology sequence in the P-nucleotlde rather than thecoding region is used in the following stage (Type II). In thelater embryonic stages, diverse V-J junctions are generatedby well-known mechanisms, such as P-nucleotide (Type III), N-regioninsertion (Type IV) or trimming of the coding ends (Type V).These findings suggest that the generation of homogeneous TCR (V2 and V5) in the early fetal stages is due to the intrinsicrearrangement mechanisms and is in stage specific manner. 相似文献