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91.
Genome profiles of bilateral dysgerminomas, a unilateral gonadoblastoma, and a metastasis from a 46, XY phenotypic female 总被引:3,自引:0,他引:3
Kildal W Kraggerud SM Abeler VM Heim S Tropé CG Kristensen GB Risberg B Lothe RA Danielsen HE 《Human pathology》2003,34(9):946-949
We present a case report of a 16-year-old, phenotypic female with bilateral dysgerminomas, a unilateral gonadoblastoma, and a peritoneal metastasis. The patient's constitutional karyotype was 46,XY. The chromosomal copy number, examined by the comparative genomic hybridization technique, showed 3 gains in the dysgerminoma of the right ovary, 6 gains in the dysgerminoma of the left ovary, and 2 gains and 1 loss in the gonadoblastoma of the left ovary. The metastasis showed 5 gains of which 4 were also observed in the dysgerminoma of the left ovary. The DNA ploidy classifications of the gonadoblastoma and the dysgerminoma in the right ovary were tetraploid, whereas the dysgerminoma in the left ovary and the metastasis were aneuploid. We therefore propose that the metastasis most probably developed from the dysgerminoma of the left ovary. 相似文献
92.
The nucleotide sequence of the Akv murine leukemia virus genome 总被引:15,自引:0,他引:15
93.
A method is described based on crossed immunoelectrophoresis of a complex antigen mixture in agarose gel followed by incubation of the gel with the monoclonal antibody. The bound monoclonal antibody is detected by the use of a secondary enzyme-labelled antibody.Using this technique we have been able to identify the precipitate arc in crossed immunoelectrophoresis of major histocompatibility complex (MHC) class I molecules in a mixture of all detergent solubilized cell membrane molecules by means of a monoclonal antibody, the specificity of which was known independently to be against MHC class I molecules. In other experiments using the same technique we demonstrated the reaction of a monoclonal antibody specific for chicken Ig light chains. 相似文献
94.
Geographical and temporal conservation of antibody recognition of Plasmodium falciparum variant surface antigens 下载免费PDF全文
Nielsen MA Vestergaard LS Lusingu J Kurtzhals JA Giha HA Grevstad B Goka BQ Lemnge MM Jensen JB Akanmori BD Theander TG Staalsoe T Hviid L 《Infection and immunity》2004,72(6):3531-3535
The slow acquisition of protection against Plasmodium falciparum malaria probably reflects the extensive diversity of important antigens. The variant surface antigens (VSA) that mediate parasite adhesion to a range of host molecules are regarded as important targets of acquired protective immunity, but their diversity makes them questionable vaccine candidates. We determined levels of VSA-specific immunoglobulin G (IgG) in human plasma collected at four geographically distant and epidemiologically distinct localities with specificity for VSA expressed by P. falciparum isolates from three African countries. Plasma levels of VSA-specific IgG recognizing individual parasite isolates depended on the transmission intensity at the site of plasma collection but were largely independent of the geographical origin of the parasites. The total repertoire of immunologically distinct VSA thus appears to be finite and geographically conserved, most likely due to functional constraints. Furthermore, plasma samples frequently had high IgG reactivity to VSA expressed by parasites isolated more than 10 years later, showing that the repertoire is also temporally stable. Parasites from patients with severe malaria expressed VSA (VSASM) that were better recognized by plasma IgG than VSA expressed by other parasites, but importantly, VSASM-type antigens also appeared to show substantial antigenic homogeneity. Our finding that the repertoire of immunologically distinct VSA in general, and in particular that of VSASM, is geographically and temporally conserved raises hopes for the feasibility of developing VSA-based vaccines specifically designed to accelerate naturally acquired immunity, thereby enhancing protection against severe and life-threatening P. falciparum malaria. 相似文献
95.
96.
Expression of CD44 in effusions of patients diagnosed with serous ovarian carcinoma – diagnostic and prognostic implications 总被引:2,自引:0,他引:2
Berner HS Davidson B Berner A Risberg B Kristensen GB Trope CG Van de Putte G Nesland JM 《Clinical & experimental metastasis》2000,18(2):197-202
CD44 is a family of cell adhesion molecules involved in a variety of cellular functions. The present study analysed the expression
of two CD44 isoforms in serous effusions of patients diagnosed with ovarian carcinoma and corresponding primary and metastatic
lesions. Fifty-eight effusions, 23 primary ovarian tumours, and 44 metastatic lesions were studied for protein expression
of CD44s and v3-10 using immunohistochemistry. Results were correlated with clinical parameters. CD44v3-10 was seen in carcinoma
cells in the majority of cases at all sites. Malignant effusions showed an up-regulation of CD44s compared to both primary
tumours and metastatic solid lesions. Mesothelial cells frequently expressed CD44s, but were rarely immunoreactive for v3-10.
CD44s immunoreactivity in cancer cells in effusions was significantly more often observed in patients with FIGO stage 3 than
in stage 4 patients (P = 0.045). Staining results did not correlate with age, effusion site, metastatic site, tumour grade or residual tumour mass
after initial surgery. Likewise, comparison of overall and disease-free survival with expression of the CD44 isoforms studied
did not reveal any statistically significant associations. The up-regulation in CD44 levels in effusions, primarily in stage
3 disease, suggests that adhesion of ovarian carcinoma cells to mesothelium may be regulated at the level of CD44s expression,
and provides further evidence of phenotypic alteration in the transition from primary tumour cell clones to effusions. The
similar expression profile of CD44 in carcinoma cells in peritoneal and pleural effusions supports our previous observations
and the hypothesis that carcinoma cells in peritoneal effusions are truly metastatic.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
97.
Tacjana Pressler Gitte Kronborg Geoffry H. Shand Bendt Mansa Niels Høiby 《Medical microbiology and immunology》1992,181(6):339-349
IgG subclass antibodies to Pseudomonas aemginosa outer membrane proteins (OMP) were investigated in serum from cystic fibrosis (CF) patients by immunoblotting and enzyme-linked immunosorbent assay (ELISA). Fifteen patients (eight in good and seven in poor clinical condition) have been followed for an average of 13 years with multiple serum samples covering the preinfection, and early and late stages of chronic infection. Laser-scanning densitometry of photographs taken from immunoblots was used to quantify antibody level and compare with ELISA titres. The earliest anti-OMP antibodies to appear were of the IgG1 subclass. There was no significant difference in IgG subclass antibody levels to OMPs between patients in relatively good and poor clinical condition. Data presented indicate a high positive correlation among measurements of IgG subclass antibodies to P. aeruginosa OMPs using ELISA and immunoblotting. 相似文献
98.
Andreassen S Riekehr C Kristensen B Schønheyder HC Leibovici L 《Artificial intelligence in medicine》1999,15(2):121-134
Causal probabilistic networks, also called Bayesian networks, allow both qualitative knowledge about the structure of a problem and quantitative knowledge, derived from case databases, expert opinion and literature to be exploited in the construction of decision support systems for diagnosis, treatment and prognosis. This mixing of qualitative and quantitative knowledge will be illustrated, using the selection of antibiotics for a subset of patients with severe infections. The subset consists of patients where bacteria or fungi have been found in the blood. A simple pathophysiological model of infection is used to calculate a prognosis, dependent on the choice of antibiotics. A decision-theoretic approach is used to balance the therapeutic benefit of antibiotic treatment against the cost of antibiotics in the form of direct monetary cost, side effects and ecological cost. A retrospective trial on patients with bacteria or fungi in the blood stemming from the urinary tract indicates that with this approach, it may be possible to suggest balanced choices of antibiotics that not only achieve greater therapeutic benefit, but also reduce the cost of therapy. 相似文献
99.
Novel mouse model of chronic Pseudomonas aeruginosa lung infection mimicking cystic fibrosis 下载免费PDF全文
Hoffmann N Rasmussen TB Jensen PØ Stub C Hentzer M Molin S Ciofu O Givskov M Johansen HK Høiby N 《Infection and immunity》2005,73(4):2504-2514
Pseudomonas aeruginosa causes a chronic infection in the lungs of cystic fibrosis (CF) patients by establishing an alginate-containing biofilm. The infection has been studied in several animal models; however, most of the models required artificial embedding of the bacteria. We present here a new pulmonary mouse model without artificial embedding. The model is based on a stable mucoid CF sputum isolate (NH57388A) with hyperproduction of alginate due to a deletion in mucA and functional N-acylhomoserine lactone (AHL)-based quorum-sensing systems. Chronic lung infection could be established in both CF mice (Cftr(tmlUnc-/-)) and BALB/c mice, as reflected by the detection of a high number of P. aeruginosa organisms in the lung homogenates at 7 days postinfection and alginate biofilms, surrounded by polymorphonuclear leukocytes in the alveoli. In comparison, both an AHL-producing nonmucoid revertant (NH57388C) from the mucoid isolate (NH57388A) and a nonmucoid isolate (NH57388B) deficient in AHL were almost cleared from the lungs of the mice. This model, in which P. aeruginosa is protected against the defense system of the lung by alginate, is similar to the clinical situation. Therefore, the mouse model provides an improved method for evaluating the interaction between mucoid P. aeruginosa, the host, and antibacterial therapy. 相似文献
100.
Hvidtjørn D Grove J Schendel D Vaeth M Ernst E Nielsen L Thorsen P 《Human reproduction (Oxford, England)》2005,20(9):2550-2551
BACKGROUND: In a Danish population-based cohort study assessing the risk of cerebral palsy in children born after IVF, we made some interesting observations regarding 'vanishing co-embryos'. METHODS and RESULTS: All live-born children born in Denmark from 1 January 1995 to 31 December 2000 were included in this analysis. The children conceived by IVF/ICSI (9444) were identified through the IVF Register, the children conceived without IVF/ICSI (395 025) were identified through The Danish Medical Birth Register. Main outcome measure was the incidence of cerebral palsy. Within the IVF/ICSI children we found indications of an increased risk of cerebral palsy in those children resulting from pregnancies, where the number of embryos transferred was higher than the number of children born. CONCLUSIONS: The association between vanishing embryo syndrome and incidence of cerebral palsy following IVF requires further investigation in larger, adequately powered, studies. 相似文献