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61.
Four monoclonal antibodies against human erythrocyte membrane antigens were established. The antigenic determinants of KOR-E1, E3, E6 were Pr1h antigen, Wrb antigen, and the trypsin sensitive portion of glycophorin A (EnaTS) respectively. The antigen recognized by KOR-E4 could not be determined. The reactivities of these antibodies with normal hematopoietic cells, malignant hematopoietic cell lines (N = 31), and fresh leukemic cells obtained from 128 patients with various types of leukemias were studied. All antibodies reacted only with erythrocytes among peripheral blood cells, and also KOR-E6 reacted only with erythroid cells among bone marrow cells. KOR-E3 had no reactivity with any cell lines examined, and KOR-E1 and KOR-E4 were reactive with some lymphoid cell lines. However, KOR-E6 had specific reactivities with erythroid (HEL, K562), megakaryocytic (CMK-1), multiphenotypic (KOPM-28), and basophilic (KU-812) cell lines. The antigen (glycophorin A) recognized by KOR-E6 was expressed on a small population of mononuclear cells separated from acute lymphoblastic leukemia (3/70), acute myelogenous leukemia (2/12), monosomy 7-myeloproliferative disorder (1/1), juvenile CML (1/1), and transient myeloproliferative disorder with Down's syndrome (4/12), although it could not be determined whether these cells were leukemic cells or not. KOR-E6 was reactive with a large population of leukemic blasts in erythroleukemia (2/2) and acute megakaryoblastic leukemia (3/6). Thus, KOR-E6 appears to be an erythroid marker of leukemic cells.  相似文献   
62.
Summary The nucleotide sequences of tRNAAsn (GUU) and tRNATyr (GUA) genes from tomato mitochondria and their flanking regions have been determined. The tomato mitochondrial tRNAAsn gene is located 2.1 kb downstream from the tRNACys gene reported previously (Izuchi and Sugita 1989) and shows a nearly complete identity with the corresponding chloroplast gene. The tRNATyr gene, which shows only 73% homology with the corresponding chloroplast gene, has to be considered a native mitochondrial tRNA gene and is 535 bp from the chloroplast-like tRNAAsn gene on the same strand. Northern hybridization analysis revealed that the three tRNA genes are transcribed in tomato mitochondria. Southern hybridization analysis of tomato, sugar beet, rice and wheat mitochondrial DNAs, with oligonucleotide probes for mitochondrial or chloroplast tRNA genes, demonstrated that the mitochondrial tRNACys gene found in tomato is present in dicot plants but not in monocots. On the other hand, a chloroplast-like tRNACys gene exists in monocot plants.  相似文献   
63.
Summary Monoclonal antibody (MCA) G-22 is directed against a human glioma-associated surface antigen. Its availability for the radioimmunodetection of human glioma was analyzed by utilizing the xenografts in athymic mice. Nude mice with subcutaneous grafts of U251-MG or U251-SP glioma received intravenous administration of 123I or 131I labeled F(ab)2 fragment or whole immunoglobulin. Results of radioimaging revealed that 123I-labeled antibody was better than the 131I-labeled. It was also noted that administration of 123I-labeled F(ab)2 fragment of G-22 MCA enabled the imaging of human glioma xenografts weighing 80–650 mg after 48 hours. When biodistribution of 123I MCA was compared between G-22 and control antibodies, the percentages of dose/g in tumors were 5.228–1.799 at 30 hours and 4.112–1.132 at 48 hours with G-22 and they were 4.164–1.248 and 0.314–0.142 with control. The tumor/blood ratio until 72 hours after injection was constantly above 1 with G-22 and less than 1 with control antibody. These results indicate the potential usefulness of G-22 MCA for the radioimmunodetection of human gliomas.  相似文献   
64.
Placement of stents for the tracheal or carinal stenosis have a meaning of maintaining the airway. Failure of the stenting causes death. In cases of severe airway stenosis and low pulmonary function, the pulmonary support method should be performed instead of intubation and mechanical ventilation. Generally, PCPS (percutaneous cardio-pulmonary support system) is used as a pulmonary support. This method was very useful to place stents for airway stenosis. We concluded that PCPS was useful in emergency cases, and in cases of severe fixed type airway stenosis and low pulmonary function it had be on stand-by.  相似文献   
65.
The authors report a 3-year-old male with glutaric aciduria type II, whose magnetic resonance imaging studies revealed agenesis of the cerebellar vermis and hypoplastic temporal lobes. Proton magnetic resonance spectroscopy in the parietal white matter revealed a markedly increased choline/creatine ratio, suggesting a demyelinating process. Gas chromatographic analysis of urinary organic acids should be studied in any patient with agenesis of the cerebellar vermis and cystic renal disease to exclude glutaric aciduria type II.  相似文献   
66.
We have examined whether propofol activates complement. In the first study, blood was mixed with saline, propofol or the lipid solvent for propofol, and the activated complement 3 (C3a) and 4 (C4a) concentrations in the supernatant were assayed. In the second study, blood and propofol were mixed with various levels of nafamostat mesilate (anti-complement agent) up to 0.3 mmol/l and the C3a was assayed. In the third study, the time course of plasma C3a concentration in patients during propofol anaesthesia was examined. The results showed that the lipid solvent activated complement and produced similar levels of C3a to propofol, probably via both the classical and alternative pathways. This activation was not inhibited by any of the nafamostat concentrations used. There was no significant change in plasma C3a concentration during propofol anaesthesia. These results suggest that C3a is generated by the lipid solvent, but its accumulation during propofol anaesthesia is minimal.  相似文献   
67.
BACKGROUND: A randomized, controlled clinical trial was conducted in 1991 to compare an intravenous megadose of methylprednisolone with a control drug (mecobalamin) for treating acute idiopathic optic neuritis. CASES: Sixty-six cases from 22 clinical centers throughout Japan were examined to evaluate the treatment on visual function parameters, such as visual acuity, visual field, color vision, contrast sensitivity, and critical flicker frequency. OBSERVATIONS: The methylprednisolone pulse treatment group showed faster recovery of visual function, particularly the visual acuity at 1 week (P<.05), Humphrey field analyzer mean deviation at 3 weeks (P<.05), and color vision at 1 week (P<.05). Recovery of contrast sensitivity at several different spatial frequencies was significant in the pulse treatment group at 1 (P<.01), 2 (P<.05), and 4 weeks (P<.05) after the start of treatment. Visual function test results at 12 weeks and 1 year were essentially the same in the two treatment groups. Side effects appeared more frequently in the pulse treatment group than in the control (P<.05). CONCLUSIONS: Pulse treatment does not appear effective for idiopathic optic neuritis even though visual function in the pulse treatment group of this trial recovered more quickly during the initial phase compared to the controls. More effective and specific treatment should be established for optic neuritis.  相似文献   
68.
We studied 132 families with a family history of breast cancer (familial aggregation cases, FA cases) to assess the breast cancer risk presented by such a family history. For comparison with these FA cases, we randomly selected 132 control families of sporadic cases (SP controls) by adjusting for the age of the proband at surgery. Information on family history was collected for all first-degree female relatives and maternal and paternal grandmothers. Japanese women with a first-degree relative affected by breast cancer were found to have an increased risk of the disease. The odds ratio (OR) for women with a family history of breast cancer was 1.99 (95% confidence interval [ CI ], 1.48-2.66). The OR for FA-case doughters of women with breast cancer was 1.54 (95% CI, 0.91-2.63). A higher risk was not observed if a woman's mother had breast cancer. If the proband had a sister with breast cancer, a slightly increased risk of other cancers of the proband was observed (OR, 1.85 [ 0.87-3.92]). These results suggest that a family history of breast cancer in Japanese women may affect their risk of developing cancer of the breast and other organs.  相似文献   
69.
A reconstituted lipid peroxidation system containing NADPH-cytochrome c reductase isolated from detergent-solubilized rat liver microsomes was used to determine the effects of several compounds, including drugs, on the lipid peroxidation activity. EDTA and ferrous ion were essential requirements for reconstitution of the activity. The addition of 1,10-phenanthroline to the system containing both EDTA and ferrous ion further enhanced the activity. Pyrocatecol, thymol, p-aminophenol, imipramine, p-chloromercuribenzoate (PCMB) and alpha-tocopherol exhibited strong inhibition, aniline, N-monomethylaniline, aminopyrine, benzphetamine, SKF 525-A and NADP exhibited moderate inhibition, and phenol, benzoic acid, acetanilide and nicotinamide exhibited less or no inhibition at the concentrations lower than 1000 micron M. Metal ions such as Hg+, Hg2+, Co2+, Cu2+, Mn2+ and U6+ inhibited lipid peroxidation strongly. In addition, Cd2+, St2+ and Ca2+ exhibited less potent to moderate inhibition, and Ba2+ and Mg2+ were without effects on the activity. Among sulfhydryl compounds tested, dithiothreitol inhibited lipid peroxidation to a greater extent than did the other three compounds, glutathione, cysteine and mercaptoethanol.  相似文献   
70.
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