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91.
To elucidate the mechanisms of metastasis, we established two sublines HPC-1H5 with a highly liver metastatic cell line and HPC-1P5a with a highly peritoneal disseminating cell line, which were sequentially selected from the parental pancreatic cancer cell line HPC-1. Using these three cell lines, we investigated several biological properties and mRNA levels of differentially-expressed genes involved in cancer metastasis by cDNA macroarray. Microscopic findings for the three cell lines were the same. The tumorigenicity, in vitro growth ability, motile activity, adhesive activity and the production of IL-8 of metastatic sublines were higher than those of parental HPC-1 cells. Particularly, HPC-1H5 cells showed clearly higher levels of IL-8 expression and tumors of HPC-1H5 cells grew faster and bigger than those of HPC-1P5a cells. In cDNA macroarray analysis of HPC-1H5 cells, 22 genes were up-regulated and 44 genes were down-regulated compared with parental HPC-1 cells. In HPC-1P5a cells, 9 genes were up-regulated and 28 genes were down-regulated compared with parental HPC-1 cells. This study provides a demonstration of global gene expression analysis of pancreatic cancer cells with liver metastasis and peritoneal dissemination. Furthermore, our results provide a new insight into the study of liver metastasis and peritoneal dissemination of human pancreatic cancer. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
92.
Recent studies have speculated on the possible role of the mother in transmitting Helicobacter pylori infection to their children. In an attempt to either prove or disprove this supposition, we investigated the rates of infection of children born to H. pylori-positive mothers from birth to 5 years of age using serology and the stool antigen test. When infection of the children did occur, the strains from the children were compared to those of their mothers using DNA analysis. Sixty-nine of the 350 pregnant mothers (19.7%) had a positive serology for H. pylori. Fifty-one children underwent serological examinations and stool antigen tests at 4 to 6 days after birth, followed by 1, 3, and 6 months. They were continuously given the stool antigen test at 4- to 6-month intervals until the age of 5 years. Gastric juice samples were collected from the infected children and their mothers for culture and DNA analyses using a random amplified polymorphic DNA fingerprinting method. None of the 51 children acquired H. pylori infection during the first year of life. Of the 44 children enrolled in a 5-year follow-up study, five (11%) acquired H. pylori infection. They acquired the infection at the age of 1 year 2 months, 1 year 3 months, 1 year 6 months, 1 year 8 months, and 4 years 4 months. Random amplified polymorphic DNA fingerprinting confirmed that the strains of the five children exhibited DNA fingerprinting patterns identical to those of their mothers. These findings suggest that mother-to-child transmission is the most probable cause of intrafamilial spread of H. pylori.  相似文献   
93.
94.
The localization of intraglomerular deposits of fibrin (Fb)/fibrinogen (Fg)-related antigen (FRA) in children with various glomerular diseases was determined by an immunohistopathologic method using an anti-Fg antibody capable of detecting FRA, an anti-D-dimer antibody capable of detecting crosslinked Fb (XLFb) and its derivatives (XLFbDP), and by a method using the effect of monochloroacetic acid (MCA) treatment on kidney sections. In proliferative glomerulonephritis (PGN), XLFbs were detected within the capillaries and extension beyond the mesangium was seen in severe PGN. The FRA within the mesangium of minimal or mild PGN was composed of the non-XLFb substance. The FRA within Bowman's space of most PGN had disappeared after MCA treatment, suggesting a non-XLFb substance. The presence of FRA within electron-dense deposits (EDD) suggested that FRA deposits are associated with immune-complex deposits in the glomeruli.  相似文献   
95.
Two new enzyme-linked immunosorbent assays (ELISAs) with chimeric fusion polypeptides for the detection of human antibodies specific to Epstein-Barr virus nuclear antigen 1 (EBNA-1) are described. One is an indirect ELISA with affinity-purified beta-galactosidase-EBNA-1 fusion protein as the antigen. The other is a "sandwich" assay based on the use of anti-beta-galactosidase antibody to capture beta-galactosidase-EBNA-1 fusion proteins in bacterial extracts. A good correlation was shown between antibody titers determined by the ELISA with the EBNA-1 fusion proteins and those determined by a conventional anticomplement immunofluorescence test which is being widely performed with Raji cells for the purpose of research and clinical diagnosis. The advantage of the ELISAs for seroepidemiologic studies on Epstein-Barr virus was demonstrated by sensitive detection of marginal immunoglobulin G antibody to the EBNA-1 domain in serum samples from patients with infectious mononucleosis.  相似文献   
96.
The pathogenesis of hepatitis C virus (HCV)-associated insulin resistance remains unclear. Therefore, we investigated mechanisms for HCV-associated insulin resistance. Homeostasis model assessment for insulin resistance was increased in patients with HCV infection. An increase in fasting insulin levels was associated with the presence of serum HCV core, the severity of hepatic fibrosis and a decrease in expression of insulin receptor substrate (IRS) 1 and IRS2, central molecules of the insulin-signaling cascade, in patients with HCV infection. Down-regulation of IRS1 and IRS2 was also seen in HCV core-transgenic mice livers and HCV core-transfected human hepatoma cells. Carbobenzoxy-l-leucyl-l-leucyl-l-leucinal, a potent proteosomal proteolysis inhibitor, blocked down-regulation of IRS1 and IRS2 in HCV core-transfected hepatoma cells. In human hepatoma cells, HCV core up-regulated suppressor of cytokine signaling (SOCS) 3 and caused ubiquitination of IRS1 and IRS2. HCV core-induced down-regulation of IRS1 and IRS2 was not seen in SOCS3(-/-) mouse embryonic fibroblast cells. Furthermore, HCV core suppressed insulin-induced phosphorylation of p85 subunit of phosphatidylinositol 3-kinase and Akt, activation of 6-phosphofructo-2-kinase, and glucose uptake. In conclusion, HCV infection changes a subset of hepatic molecules regulating glucose metabolism. A possible mechanism is that HCV core-induced SOCS3 promotes proteosomal degradation of IRS1 and IRS2 through ubiquitination.  相似文献   
97.
The nuclear factor kappa-B 2 (NFKB2) gene is a member of the NFKB/Rel gene family, which is known to be a pivotal regulator of the acute phase of the inflammatory response and of immune responses. We identified three novel single nucleotide polymorphisms (SNPs) and determined their allelic frequencies, as determined by the sequencing of 48 alleles of the entire gene in a Japanese population sample. Two of the three polymorphisms were identified at nucleotide (nt) position 1837 (T/C) and nt position, 1867 (GG/G) in the upstream region of the gene. The other polymorphism was identified at nt position 2584 (G/T) within intron 1. These polymorphisms will be useful in genetic studies of the processes involved in inflammatory responses and in bone differentiation. Received: October 17, 2000 / Accepted: October 23, 2000  相似文献   
98.
S Nakajima  K Nakajima  A P Kendal 《Virology》1983,131(1):116-127
We have determined nucleotide sequences of the HA1 portion of the hemagglutinin (HA) gene of the parental A/USSR/90/70 (H1N1) virus and its eight variants selected in vitro with six monoclonal antibodies to study antigenic determinants. The HA1 gene of one of the variants (B-1-23) was cloned in bacteria and its nucleotide sequence was determined by the Maxam-Gilbert method. The nucleotide sequence of the variant was confirmed by the dideoxy chain termination method. The gene sequences of the other viruses were determined by the latter method. Three variants with reduced reactivity in HI test only with the selecting antibodies possessed one amino acid substitution. On the other hand, most other variants which had the changed reactivity to multiple antibodies in HI test possessed more than one substitution. Comparison of the amino acid sequences of the HA1 molecule, deduced from the nucleotide sequences, suggested that the monoclonal antibodies W18 and 264 reacted with epitopes located on the area involving amino acid residues 125C and 189-190, respectively, whereas, the antibodies 22 and 70 reacted with epitopes involving amino acid residues 129, 132, and 157. The epitope recognized by antibody 110 overlapped with that of W18, and the epitope recognized by antibody 385 was located on the area involving at least amino acid residues 129, 159, and 189, which overlapped with some of the above epitopes. The sequence analysis with B-1-23 variant selected with antibody 264 clearly showed that in A/USSR/77 viruses, a single substitution at amino acid residue 190 effectively changes the epitope and caused a significant antigenic variation detectable by postinfection ferret sera.  相似文献   
99.
Chromosome 1p36 deletion syndrome is characterized by hypotonia, moderate to severe developmental and growth retardation, and characteristic craniofacial dysmorphism. Muscle hypotonia and delayed motor development are almost constant features of the syndrome. We report a 4-year-old Japanese girl with 1p36 deletion syndrome whose muscle pathology showed congenital fiber type disproportion (CFTD) myopathy. This is the first case report of 1p36 deletion associated with CFTD. This association may indicate that one of the CFTD loci is located at 1p36. Ski proto-oncogene −/− mice have phenotypes that resemble some of the features observed in patients with 1p36 deletion syndrome. Because fluorescent in situ hybridization analysis revealed that the human SKI gene is deleted in our patient, some genes in 1p36, including SKI proto-oncogene, may be involved in muscle hypotonia and delayed motor development in this syndrome. Received: March 4, 2002 / Accepted: July 7, 2002  相似文献   
100.
Summary Experimental infection with HVJ (haemagglutinating virus of Japan—the Sendai strain of parainfluenza 1 virus) in mice was studied. Aerosol infection of newborn mice with the wild-type virus (HVJ-W) retarded the development of body weight and killed the animals within a few weeks. Large amounts of virus were isolated from both the lungs and the nasal turbinates of infected mice. In contrast, newborn mice exposed by inhalation to a temperature-sensitive(ts) mutant (HVJ-pB) derived from an HVJ carrier culture showed no clinical signs and grew equally well as mock-infected animals. No infectious virus could be recovered from the lungs although thets mutant grew to moderate titre in the nasal turbinates.The prior inoculation of newborn mice with thets mutant virus induced a state of significant resistance to subsequent challenge with the virulent wild-type virus.No replication of challenge virus in both lungs and nasal turbinates could be detected and the animals were protected a lethal infection. It is suggested that an avirulent temperature-sensitive mutant which has lost the capacity to replicate in the lower respiratory tract but is still capable of multiplying in the nasal turbinates may be a promising candidate for use in live vaccines especially against the infectious disease of the lower respiratory tract.With 2 Figures  相似文献   
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