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1.
2.
A series of 5-aminomethinimino-3-methyl-4-isoxazolecarboxylic acid phenylamides 4 has been prepared by condensation of 5-amino-3-methyl-4-isoxazolecarboxylic acid phenylamides 1 with trichloroacetic aldehyde. Alcoholysis of trichloro derivatives 2 gave 5-alkoxymethine derivatives 3 which, on reaction with an appropriate amine, formed the corresponding compounds 4 . The compounds obtained were evaluated for their immunological activity. The properties of three compounds, described in this report, permitted inhibition of the immune response in all possible ways: diminishing both types of immune response ( 4d ), humoral immune response ( 4a ), or cellular immune response ( 4c ). Preparation 4d is comparable in its effectiveness to CsA, so it may be potentially used as an agent for prolongation of the function of transplanted organs. Two other compounds may potentially be used in cases where only one type the immune response is required for combating pathogen invasion.  相似文献   
3.
Intoxication of rats with mercuric chloride (0.5 mg Hg/kg of body weight, daily for 10 weeks) increased the hepatic contents of soluble and insoluble collagen and elastin. The increase was associated with elevated serum aminotransferase and alkaline phosphatase activities, and decreased total protein level in serum. Inflammatory changes were found in the liver. An increase in the fibrous protein content suggests that inflammatory reaction to mercuric chloride can result in hepatic fibrosis.  相似文献   
4.
Non-competitive, sandwich enzyme immunoassay for both penicillin amidases from Escherichia coli is described. The assay involves the use of monospecific antibodies and their conjugates. The amidases inactivated by heating and by acid- or alkali-treatment cannot be assayed. Reproducible results for each amidase were achieved within 5-6 hours in the range of 3-500 ng/ml (0.25-40 mU/ml) and coefficient of variation was 13%.  相似文献   
5.
Hybridomas secreting monoclonal antibodies specific for Pseudomonas aeruginosa outer membrane antigens were isolated. One of the antibodies was highly specific for the O antigen of the lipopolysaccharide of International Antigen Typing Scheme serotype 5 strains, reacting only weakly with a serotype 17 strain and failing to react with the outer membranes of strains representing 15 other serotypes. This monoclonal antibody was able to agglutinate heat-killed bacterial cells as well as lipopolysaccharide-coated sheep erythrocytes. Two other monoclonal antibodies were able to interact with the outer membranes of strains representing all 17 serotypes, although they were unable to agglutinate heat-killed bacterial cells. One of these was shown to be specific for the major outer membrane lipoprotein H2. The antigenic site against which this monoclonal antibody reacted was present in the outer membranes of two Pseudomonas fluorescens strains, two Pseudomonas putida strains, a Pseudomonas anguilliseptica strain, and an Azotobacter vinelandii strain, but not in the outer membranes of five other bacterial species.  相似文献   
6.
We report on a familial three way translocation involving chromosomes 3, 6, and 15 identified by prometaphase banding and fluorescence in situ hybridisation (FISH). Two mentally retarded sibs with different phenotypic abnormalities, their phenotypically normal sister and mother, and two fetuses of the phenotypically normal sister were analysed. The terminal regions of chromosomes 3q, 6q, and 15q were involved in a reciprocal translocation, in addition to a paracentric inversion of the derivative chromosome 15. Conventional cytogenetic studies with high resolution GTG banding did not resolve this rearrangement. FISH using whole chromosome paints (WCPs) identified the chromosomal regions involved, except the aberrant region of 3q, which was undetectable with these probes. Investigation of this region with the subtelomeric FISH probe D3S1445/D3S1446 showed a balanced karyotype, 46,XX,t(3;15;6) (q29;q26.1;q26), inv der(15) (q15.1q26.1) in two adult females and one fetus. It was unbalanced in two sibs, showing two different types of unbalanced translocation resulting in partial trisomy 3q in combination with partial monosomy 6q in one patient and partial trisomy 15q with partial monosomy 6q in the other patient and one fetus. These represent apparently new chromosomal phenotypes.  相似文献   
7.
From Escherichia coli PCM 271 cells two penicillin amidases were separated by affinity chromatography on immunoadsorbent column. In cells grown in organic medium the activities of the amidase 1 and 2 were 30 and 70% respectively, whereas the activity of the amidase 1 in the cells grown in inorganic medium increased up to 98%. The amidase 1 migrated faster in polyacrylamide gel electrophoresis and was retained on DEAE-cellulose in 10 mM phosphate buffer, pH 8. No catalytic differences were demonstrated between the amidases.  相似文献   
8.
A typology of 156 convicted driving-while-intoxicated (DWI) offenders was developed using cluster analysis and external validation procedures. The typology was derived from 4 variables (alcohol dependence severity, psychiatric severity, bad-driving index, and social instability) selected to maximize the feasibility of performing treatment matching with DWI offenders. Five clusters that suggested specific treatment matching opportunities were identified. The largest, Cluster 4 (31% of cases), showed a low problem profile. However, a moderate-severity group (Cluster 1), a high-risk driver group (Cluster 2), and two high problem-severity groups (Clusters 3 and 5) were also found. Clusters 3 and 5 had high levels of alcohol dependence and psychiatric symptoms but differed significantly on social instability.  相似文献   
9.
The Fc gamma receptor of guinea-pig peritoneal macrophages was purified by affinity chromatography by using rabbit IgG or guinea-pig IgG2 coupled to Sepharose. Lysates prepared by treatment of 125I-labeled macrophages with NP-40 were first applied to BSA-Sepharose and then to IgG-Sepharose and eluted with 0.5 M acetic acid containing 1% NP-40. The specific binding was determined by interaction of the 125I-labeled receptor with IgG-Sepharose in the presence and absence of soluble IgG. The specific binding of the purified receptor was 42-82%. Interactions of the purified receptor with IgG-Sepharose were equally well inhibited by soluble rabbit IgG or guinea-pig IgG2, but not by F(ab')2 fragments. Inclusion of NP-40 in the buffer used in the assay reduced nonspecific binding of the receptor to the affinity gels. The purified receptor can be stored for 20 days at 4 degrees C without a significant loss of the specific binding activity. Analysis of the receptor by SDS-polyacrylamide gel electrophoresis, under nonreducing and reducing conditions, revealed two major peaks of radioactivity corresponding to mol. wts of about 50,000 and 25,000, and one very minor peak corresponding to a mol. wt of about 30,000. The results obtained suggest that the protein of the second major peak is a product of the dissociation of the protein of the first major peak rather than a product of its reduction by 2-mercaptoethanol.  相似文献   
10.
Virulent, viable Shigella sonnei bacilli introduced orally, induced in mice resistance against lethal intravenous (i.v.) infection with dysentery bacilli. The immunized animals survived lethal infection and also bacilli were effectively destroyed in the spleen and liver of the immunized animals. It was shown that orally induced immunity may be transferred into nonimmunized mice by means of serum and spleen cells taken on definite days after immunization of donors. Protective activity of serum appeared to be dependent on the presence of specific antibodies and was correlated with their titer. Protective activity of spleen cells occurred about 6 days after immunization of the cell donors with the bacilli. Cell suspensions, prepared from the spleens taken from donors on day 6, protected 100% of the recipients of these cells from lethal infection. Results of these studies indicate that bacterial infection developing in the intestine mobilizes besides local immunity also general immunity. Mechanism of the general immunity induced by orally administered dysentery bacilli is discussed.  相似文献   
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