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排序方式: 共有9195条查询结果,搜索用时 15 毫秒
91.
92.
Ventricular function in the newborn lamb 总被引:5,自引:0,他引:5
Downing S. Evans; Talner Norman S.; Gardner Thomas H. 《The American journal of physiology》1965,208(5):931-937
93.
Hereditary adenomatosis, particularly familial polyposis coli (FPC) and Gardner's syndrome (GS), has been investigated from family pedigrees and chromosomal markers for precancer and cancer. FPC and GS are much alike in phenotypes. Studies are in progress to determine if the two adenomatous diseases are controlled by the same DNA sequence. Chromosome numerical and structural instability is a good diagnostic criterion for hereditary adenomatous diseases where risk factors are already determined to the level of 0.5 probability from pedigree analysis. This has been applied successfully at the pediatric age level to identify family members who carry the gene but have no adenomas in the colorectum. Sister chromatid exchange (SCE) did not distinguish plasma samples from FPC, GS, or solitary adenoma patients form each other or from controls with no adenomas. SCE did distinguish invasive from recurrent and noninvasive cancer. The chromosome #2 polymorphism observed at 2q-21.3 has not been confirmed as a deletion, but is under investigation with more refined methods. 相似文献
94.
95.
96.
Human papillomavirus types in anogenital warts of children 总被引:3,自引:0,他引:3
Tissue from anogenital warts of 25 children, 10 of whom were suspected of being victims of sexual abuse, was investigated by dot blot and Southern blot techniques for human papillomavirus (HPV) types. HPV DNA was detected in 22 children, two of whom had double infections. The genital HPV types 6 and/or 11 were detected in 20 children, and in three children other HPV types were found. One had HPV 18 (as well as 11); in a second child a possible skin type, HPV 2, was detected; and the third child was infected with an unidentified type. In three cases genital wart material was available from one of the parents, and in all three the HPV type was the same as that of the child. For nine other children one or both parents were reported to have genital warts. The source of infection appeared to be the adult genital tract, but sexual contact might not be the only means of transmission. 相似文献
97.
Mutational analysis of the SOX9 gene in campomelic dysplasia and autosomal sex reversal: lack of genotype/phenotype correlations 总被引:9,自引:1,他引:9
Meyer J; Sudbeck P; Held M; Wagner T; Schmitz ML; Bricarelli FD; Eggermont E; Friedrich U; Haas OA; Kobelt A; Leroy JG; Van Maldergem L; Michel E; Mitulla B; Pfeiffer RA; Schinzel A; Schmidt H; Scherer G 《Human molecular genetics》1997,6(1):91-98
It has previously been shown that, in the heterozygous state, mutations in
the SOX9 gene cause campomelic dysplasia (CD) and the often associated
autosomal XY sex reversal. In 12 CD patients, 10 novel mutations and one
recurrent mutation were characterized in one SOX9 allele each, and in one
case, no mutation was found. Four missense mutations are all located within
the high mobility group (HMG) domain. They either reduce or abolish the
DNA-binding ability of the mutant SOX9 proteins. Among the five nonsense
and three frameshift mutations identified, two leave the C-terminal
transactivation (TA) domain encompassing residues 402-509 of SOX9 partly or
almost completely intact. When tested in cell transfection experiments, the
recurrent nonsense mutation Y440X, found in two patients who survived for
four and more than 9 years, respectively, exhibits some residual
transactivation ability. In contrast, a frameshift mutation extending the
protein by 70 residues at codon 507, found in a patient who died shortly
after birth, showed no transactivation. This is apparently due to
instability of the mutant SOX9 protein as demonstrated by Western blotting.
Amino acid substitutions and nonsense mutations are found in patients with
and without XY sex reversal, indicating that sex reversal in CD is subject
to variable penetrance. Finally, none of 18 female patients with XY gonadal
dysgenesis (Swyer syndrome) showed an altered SOX9 banding pattern in SSCP
assays, providing evidence that SOX9 mutations do not usually result in XY
sex reversal without skeletal malformations.
相似文献
98.
Leung NJ Aldovini A Young R Jarvis MA Smith JM Meyer D Anderson DE Carlos MP Gardner MB Torres JV 《Virology》2000,268(1):94-103
Development of an effective preventive or therapeutic vaccine against HIV-1 is an important goal in the fight against AIDS. Effective virus clearance and inhibition of spread to target organs depends principally on the cellular immune response. Therefore, a vaccine against HIV-1 should elicit virus-specific cytotoxic lymphocyte (CTL) responses to eliminate the virus during the cell-associated stages of its life cycle. The vaccine should also be capable of inducing immunity at the mucosal surfaces, the primary route of transmission. Recombinant Bacille Calmette-Guérin (BCG) expressing viral proteins offers an excellent candidate vaccine in view of its safety and ability to persist intracellularly, resulting in the induction of long-lasting immunity and stimulation of the cellular immune response. BCG can be administered orally to induce HIV-specific immunity at the mucosal surfaces. The immunogenicity of four recombinant BCG constructs expressing simian immunodeficiency virus (SIV) Gag, Pol, Env, and Nef proteins was tested in rhesus macaques. A single simultaneous inoculation of all four recombinants elicited SIV-specific IgA and IgG antibody, and cellular immune responses, including CTL and helper T cell proliferation. Our results demonstrate that BCG recombinant vectors can induce concomitant humoral and cellular immune responses to the major proteins of SIV. 相似文献
99.
Susan E. Gardner Donald C. Anderson Bette J. Webb Ann E. Stitzel Morven S. Edwards Roger E. Spitzer Carol J. Baker 《Infection and immunity》1982,35(3):800-808
The relative roles of serum factors required for opsonization of type XIV Streptococcus pneumoniae were investigated by means of luminol-enhanced chemiluminescence (CL), bactericidal, and immunofluorescence assays employing adult sera containing high (>1,000 ng of antibody nitrogen per ml) or low (<200 ng of antibody nitrogen per ml) antibody concentrations as determined by radioimmunoassay. Specific antibody concentration correlated directly with both total and heat-labile CL activity (P < 0.005) and with the bactericidal index (P < 0.05) at a serum concentration of 10%. The importance of specific antibody as an opsonin was confirmed by the abolition of CL activity and immunoglobulin immunofluorescence observed after absorption of heated sera with type XIV pneumococcal cells and by the dose response in CL and bactericidal activity observed with the addition of immunoglobulin G to hypogammaglobulinemic serum. A role for the classical complement pathway in opsonization was indicated by significantly greater CL integrals for high-antibody sera than for low-antibody sera depleted of factor D and by the bactericidal activity noted for untreated, but not magnesium ethylene glycol-bis(β-aminoethyl ether)-N,N-tetraacetic acid-chelated low-antibody sera. The alternative pathway contributed more than half of the CL activity of both high- and low-antibody sera. However, after magnesium ethylene glycol-bis(β-aminoethyl ether)-N,N-tetraacetic acid chelation, only sera with high antibody concentrations or agammaglobulinemic serum reconstituted with immunoglobulin G with high specific antibody levels supported significant bactericidal activity. Therefore, type-specific antibody and complement promote opsonization of type XIV S. pneumoniae, and this may occur via either complement pathway. These results suggest that CL is a suitable tool to delineate serum factors and their contribution to opsonization, but results must be related to other functional assays. 相似文献
100.
High-level expression of EphA2 receptor tyrosine kinase in prostatic intraepithelial neoplasia 总被引:11,自引:0,他引:11 下载免费PDF全文
Zeng G Hu Z Kinch MS Pan CX Flockhart DA Kao C Gardner TA Zhang S Li L Baldridge LA Koch MO Ulbright TM Eble JN Cheng L 《The American journal of pathology》2003,163(6):2271-2276
EphA2 is a transmembrane receptor tyrosine kinase that is overexpressed in many carcinomas. Specific targeting of EphA2 with monoclonal antibodies is sufficient to inhibit the growth, migration and invasiveness of aggressive cancers in animal models. Using immunohistochemical analyses, we measured the expression of EphA2 in prostatic adenocarcinoma, high-grade prostatic intraepithelial neoplasia, and adjacent benign prostate tissue from ninety-three radical prostatectomy specimens. These results were related to multiple clinical and pathologicalcharacteristics. The fraction of cells staining positively with EphA2 in benign prostatic epithelium (mean, 12%) was significantly lower than that in high-grade prostatic intraepithelial neoplasia (mean, 67%, P < 0.001) and prostatic adenocarcinoma (mean, 85%, P < 0.001). Moreover, the intensity of EphA2 immunoreactivity in prostatic adenocarcinoma was significantly higher than in benign prostatic tissue (P < 0.001) or high-grade prostatic intraepithelial neoplasia (P < 0.001). Benign prostatic epithelium showed weak or no immunoreactivity for EphA2 in all cases examined. Whereas EphA2 immunoreactivity related to neoplastic transformation, it did not correlate with other clinical and pathological parameters examined. Our data suggest that EphA2 levels increase as prostatic epithelial cells progress toward a more aggressive phenotype. Progressively higher levels of EphA2 in high-grade prostatic intraepithelial neoplasia and prostatic carcinoma are consistent with recent evidence that EphA2 functions as a powerful oncogene. Moreover, the presence of high levels of EphA2 in these cells suggests opportunities for prostate cancer prevention and treatment. 相似文献