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71.
Purification of a gelatin-degrading type IV collagenase secreted by ras oncogene-transformed fibroblasts 总被引:3,自引:0,他引:3
C Spinucci S Zucker J M Wieman R M Lysik B Imhof N Ramamurthy L A Liotta H Nagase 《Journal of the National Cancer Institute》1988,80(17):1416-1420
Connective tissue matrix-degrading metalloproteinases play an important role in cancer invasion. In this report we describe the isolation of a metalloproteinase exhibiting both type IV collagenolytic and gelatinolytic activities from the conditioned medium of NIH-3T3 fibroblasts transformed with DNA containing an activated c-Harvey-ras oncogene from T24 bladder cancer cells. This tumor proteinase was purified by anion exchange chromatography, zinc-chelate Sepharose chromatography, and gel permeation chromatography. The final product was homogeneous on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (relative molecular mass = 67,000). Gelatin zymography revealed two bands of gelatinolytic activity, corresponding to molecular weights of 67,000 and 62,000. Upon immunoblotting with the use of an affinity-purified polyclonal rabbit antibody to a peptide region of type IV collagenase that lacks homology with interstitial collagenase or stromelysin, the purified tumor enzyme was identified as type IV collagenase. 相似文献
72.
73.
N-(2-Naphthyl)glycine hydrazide analogues were synthesized and tested for possible in vitro antitubercular activity. N-(2-Naphthyl)alanine hydrazide (3), N-methyl-N-(2-naphthyl)glycine hydrazide (5), N-(6-methoxy-2-naphthyl)glycine hydrazide (7), and 3-(2-naphthylamino)butyric acid hydrazide (23) showed potent inhibitory action against Mycobacterium tuberculosis H37Rv in Youman's medium at concentrations ranging from 0.5 to 10.0 micrograms/mL. These compounds showed significant inhibitory action against isonicotinic acid hydrazide and streptomycin-resistant strains of M. tuberculosis. N-(6-Quinolyl)glycine hydrazide (18) and 3-(2-quinolylamino)butyric acid hydrazide (24), which are bioisosteres of compounds 1 and 23, showed loss of antitubercular activity at low concentrations. 相似文献
74.
A randomized trial of intrapartum versus immediate postpartum treatment of women with intra-amniotic infection 总被引:3,自引:0,他引:3
A randomized trial of intrapartum versus postpartum antibiotic treatment of women with intra-amniotic infection was conducted. Intra-amniotic infection was treated with ampicillin and gentamicin during labor (at the time of diagnosis) in 26 women and immediately after umbilical cord clamping in 19 women. Intrapartum treatment led to a lower incidence of neonatal sepsis (0 versus 21%; P = .03) and a shorter neonatal hospital stay (3.8 versus 5.7 days; P = .02) when compared with postpartum treatment. There were no significant differences in the microbiologic results, the gestational age, or the birth weight between the groups. Intrapartum-treated mothers had a shorter mean postpartum stay, a lower mean number of febrile days, and a lower mean peak postpartum temperature than did postpartum-treated mothers; these differences were all statistically significant (P = .05). The treatment of clinical intra-amniotic infection during labor results in improved outcome. 相似文献
75.
Neonatal serologic response at term to the genital mycoplasmas 总被引:1,自引:0,他引:1
M J Dinsmoor R S Ramamurthy G H Cassell R S Gibbs 《The Pediatric infectious disease journal》1989,8(8):487-491
Genital mycoplasmas are frequently found in the amniotic fluid (AF) of women with ruptured membranes but are infrequent pathogens in the neonates born to these women. The serologic response to the genital mycoplasmas, Mycoplasma hominis and Ureaplasma urealyticum, was studied in 35 mother-baby pairs following term deliveries. Amniotic fluid and neonatal surface cultures were obtained in all cases, as were maternal and neonatal acute and convalescent sera. Despite significant maternal serologic response, there was essentially no neonatal response. Mothers with M. hominis in the AF were significantly more likely than those with negative cultures for M. hominis to exhibit IgG seroconversion and had significantly greater changes in IgG concentrations. Their infants, however, did not exhibit a significant seroresponse regardless of the AF and neonatal culture results. There was also a significant maternal seroresponse to U. urealyticum. However, this did not correlate with the presence of U. urealyticum in the AF. Significantly fewer neonates exhibited a seroresponse to U. urealyticum, again with no relation to culture results. 相似文献
76.
A P Winnie J T Hartman H L Meyers S Ramamurthy V Barangan 《Anesthesia and analgesia》1972,51(6):990-1003
77.
O'Connor RD Gilmore AS Manjunath R Stanford RH Legorreta AP Jhingran PM 《Current medical research and opinion》2006,22(3):453-461
OBJECTIVE: Clinical trials have demonstrated improved efficacy of fluticasone propionate/salmeterol (100/50 mcg) in a single device (FSC) compared with montelukast (10 mg) (MON). This study was designed to assess asthma control, asthma-related quality of life, asthma-related emergency department (ED) visit/hospitalization, treatment-related satisfaction, and productivity losses in patients newly started on FSC or MON. RESEARCH DESIGN AND METHODS: Patients who were newly prescribed FSC or MON during a regularly scheduled office visit were enrolled in a prospective observational study by nearly 500 physicians from eight managed care plans. Patient survey data were collected at baseline and at months 1, 3, 6, and 12, to measure study outcomes. ED visits/inpatient stays were reported from commercial claims data. Multivariate analyses assessed 12-month outcomes, controlling for several baseline patient characteristics. RESULTS: A total of 1414 patients >or= 15 years old were enrolled in the registry (FSC, n = 1061; MON, n = 353), 90% of which completed a 12-month survey. FSC patients had significantly greater improvement in both asthma control and quality of life, and reported significantly higher satisfaction with their medication (p = 0.003) and fewer days at work/school with asthma symptoms (p = 0.04) than MON. Other parameters of productivity losses such as missed work/school days due to asthma were not significantly different between the two groups. FSC use was also significantly associated with a lower risk of an asthma-related ED visit/hospitalization compared with MON (odds ratio = 0.35, 95% confidence interval: 0.15-0.92). CONCLUSION: In a 12-month office-based observational study, patients age 15 and older with persistent asthma, newly started on FSC, improved in symptom, quality of life, treatment, and utilization-related outcomes compared with patients newly started on MON. These results should be interpreted in light of the inherent limitations of non-randomized, uncontrolled studies. 相似文献
78.
Balasubramanya R Garg P Sharma S Vemuganti GK 《Journal of refractive surgery (Thorofare, N.J. : 1995)》2006,22(6):616-617
PURPOSE: To report a case of Acanthamoeba infection following LASIK. METHODS: A 20-year-old woman developed pain, redness, decreased vision, and corneal infiltrate in the right eye 15 days after bilateral LASIK. She did not use contact lenses postoperatively. Patient examination 3 months after surgery revealed a large, central, full-thickness corneal infiltrate with multiple satellite lesions in the right eye. Corneal scrapings were taken and the flap excised, and submitted for histopathologic examination. RESULTS: Microscopic examination of smears revealed Acanthamoeba cysts and non-nutrient agar showed a significant growth of Acanthamoeba. Histopathology examination of the excised flap demonstrated numerous Acanthamoeba cysts in tissue sections. The infiltrate was treated with a combination of topical polyhexamethylene biguanide, chlorhexidine, atropine sulfate, and oral itraconazole and resolved within 2 months. CONCLUSIONS: Laser in situ keratomileusis can be complicated by Acanthamoeba infection. Microbiologic evaluation is essential for accurate early diagnosis and treatment. 相似文献
79.
Sharma N Balasubramanya R Sinha R Titiyal JS Vajpayee RB 《Journal of refractive surgery (Thorofare, N.J. : 1995)》2006,22(4):396-401
PURPOSE: To review the indications, techniques, and results of retreatment LASIK. METHODS: Review of the literature and the authors' experience. RESULTS: Patient selection is the key to successful LASIK enhancement. The enhancement procedure should generally be undertaken 3 months after the initial LASIK procedure. Relifting of the flap may be done easily within 1 year of previous LASIK surgery. A new LASIK flap is required in cases with previously complicated LASIK. LASIK retreatment by lifting the flap is an effective and safe procedure. Overall improvement is seen in uncorrected visual acuity (> or = 20/20 and > or = 20/40) and postoperative spherical equivalent refraction within +/- 0.5 D and +/- 1.0 D. CONCLUSIONS: LASIK retreatment is an effective modality to treat regressions and residual refractive errors. 相似文献
80.