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991.
Diaz F Chai HB Mi Q Su BN Vigo JS Graham JG Cabieses F Farnsworth NR Cordell GA Pezzuto JM Swanson SM Kinghorn AD 《Journal of natural products》2004,67(3):352-356
Cytotoxicity-based, bioassay-guided fractionation of the chloroform-soluble extracts of both the roots and leaves of Picramnia latifolia led to the isolation of two new anthrone C-glycosides, picramniosides G (1) and H (2), two new oxanthrone C-glycosides, mayosides D (3) and E (4), and a new benzanthrone natural product, 6,8-dihydroxy-10-methyl-7H-benz[de]anthracen-7-one (5), together with 10 known compounds, 6,8-dihydroxy-4-methyl-7H-benz[de]anthracen-7-one (6), nataloe-emodin (7), chrysophanein, chrysophanol, 1,5-dihydroxy-7-methoxy-3-methylanthraquinone, pulmatin, 7-hydroxycoumarin, 7-hydroxy-6-methoxycoumarin, beta-sitosterol, and beta-sitosterol glucoside. The structures of 1-5 were established by spectroscopic methods, including 1D and 2D NMR, HRMS, and CD data interpretation. The cytotoxic activity of all isolates was evaluated in a small panel of human cancer cell lines. Compound 7 exhibited significant in vitro cytotoxic activity in the tested cell lines, but no significant activity was observed with an in vivo hollow fiber model at doses of 6.25, 12.5, 25, and 50 mg/kg/injection. 相似文献
992.
Angèle S Falconer A Edwards SM Dörk T Bremer M Moullan N Chapot B Muir K Houlston R Norman AR Bullock S Hope Q Meitz J Dearnaley D Dowe A Southgate C Ardern-Jones A Easton DF Eeles RA Hall J 《British journal of cancer》2004,91(4):783-787
The risk of prostate cancer is known to be elevated in carriers of germline mutations in BRCA2, and possibly also in carriers of BRCA1 and CHEK2 mutations. These genes are components of the ATM-dependent DNA damage signalling pathways. To evaluate the hypothesis that variants in ATM itself might be associated with prostate cancer risk, we genotyped five ATM variants in DNA from 637 prostate cancer patients and 445 controls with no family history of cancer. No significant differences in the frequency of the variant alleles at 5557G>A (D1853N), 5558A>T (D1853V), ivs38-8t>c and ivs38-15g>c were found between the cases and controls. The 3161G (P1054R) variant allele was, however, significantly associated with an increased risk of developing prostate cancer (any G vs CC OR 2.13, 95% CI 1.17-3.87, P=0.016). A lymphoblastoid cell line carrying both the 3161G and the 2572C (858L) variant in the homozygote state shows a cell cycle progression profile after exposure to ionising radiation that is significantly different to that seen in cell lines carrying a wild-type ATM gene. These results provide evidence that the presence of common variants in the ATM gene, may confer an altered cellular phenotype, and that the ATM 3161C>G variant might be associated with prostate cancer risk. 相似文献
993.
994.
Hao C Song JH Hsi B Lewis J Song DK Petruk KC Tyrrell DL Kneteman NM 《Cancer research》2004,64(23):8502-8506
Tumor necrosis factor (TNF) family ligand TNF-alpha and Fas ligand (FasL) can trigger apoptosis in solid tumors, but their clinical usage has been limited by hepatotoxicity. TNF-related apoptosis-inducing ligand (TRAIL) is a newly identified member of the TNF family, and its clinical application currently is under a similar debate. Here, we report a recombinant soluble form of human TRAIL (114 to 281 amino acids) that induces apoptosis in tumor cells but not human hepatocytes. We first isolated human hepatocytes from patients and showed that the human hepatocytes expressed Fas but no TRAIL death receptor DR4 and little DR5 on the cell surface. Antibody cross-linked FasL, but not TRAIL, triggered apoptosis of the human hepatocytes through cleavage of caspases. We then examined TRAIL hepatotoxicity in severe combined immunodeficient/Alb-uPA chimeric mice harboring human hepatocytes. Intravenous injection of FasL, but not TRAIL, caused apoptotic death of human hepatocytes within the chimeric liver, thus killing the mice. Finally, we showed that repeated intraperitoneal injections of TRAIL inhibited intraperitoneal and subcutaneous tumor growth without inducing apoptosis in human hepatocytes in these chimeric mice. The results indicate that the recombinant soluble human TRAIL has a profound apoptotic effect on tumor cells but is nontoxic to human hepatocytes in vitro and in vivo. 相似文献
995.
996.
Camphausen K Ménard C Sproull M Goley E Basu S Coleman CN 《International journal of radiation oncology, biology, physics》2004,58(5):1064-1539
PURPOSE: Previous studies have demonstrated that urinary 8-iso-prostaglandin F (PGF)2alpha serves as a powerful biomarker of lipid peroxidation in diseases in which oxidative stress plays an important role in its pathophysiology. The goal of this study was to measure the urinary isoprostane levels in patients with prostate cancer treated with radiotherapy (RT) in an effort to determine whether isoprostane levels are elevated compared with in historical controls, whether the levels increase after RT, and whether such an increase would correlate positively with the degree of GU symptoms during treatment. METHODS AND MATERIALS: Urine samples were obtained before and during RT from patients enrolled on a recently reported Phase III trial examining the therapeutic efficacy of ibuprofen in decreasing the acute urinary symptoms of RT. Radioimmunoassays were performed on urine samples for 8-iso-PGF2alpha or 15-keto-dihydro-PGF2alpha. RESULTS: Fifteen patients provided samples both before and during RT. The levels of 8-iso-PGF(2alpha) and 15-keto-dihydro-PGF2alpha in the urine samples obtained before prostate RT (0.27 and 0.41 nmol/mmol creatinine) did not differ appreciably from the values observed in a normal cohort (0.27 and 0.46 nmol/mmol creatinine) and did not change after RT (0.23 and 0.37 nmol/mmol creatinine). CONCLUSION: We were unable to detect an increase in either 8-iso-PGF2alpha or 15-keto-dihydro-PGF2alpha in the urine of patients with prostate cancer compared with in historical normal controls. We were also unable to measure an increase in either of the eicosanoids during RT to the prostate gland. 相似文献
997.
Parker C Warde P Norman A Panzarella T Catton C Horwich A Huddart R Dearnaley D 《International journal of radiation oncology, biology, physics》2004,58(1):53-58
PURPOSE: Serum hemoglobin level (Hb) is a significant determinant of treatment outcome after radical radiotherapy (RT) for several cancer types, but its importance in prostate cancer is not well established. METHODS AND MATERIALS: Two treatment-specific cohorts of men with localized prostate cancer (T1-4, Nx/N0, M0) were analyzed. Seven hundred six men who received radical RT at Princess Margaret Hospital between 1987 and 2000 comprise the RT-alone cohort, of whom 536 had a pre-RT Hb. Six hundred fifty-eight men received 3-6 months' neoadjuvant androgen deprivation (NAD) and radical RT at Royal Marsden Hospital between 1989 and 2000 and comprise the NAD + RT cohort, of whom 475 had a pre-NAD Hb and 513 a pre-RT Hb. Time to biochemical failure (TTBF) was the primary end point. Univariate and multivariate analyses using the Cox proportional hazards regression model were used for each data set independently to study the prognostic role of pre-RT Hb, pre-NAD Hb, nadir Hb (lowest Hb during RT), Hb decrement (pre-NAD Hb - pre-RT Hb), Gleason score, presenting PSA, and T stage. RESULTS: On univariate analysis, no significant association was seen between TTBF and any of the Hb variables for either data set. On multivariate analysis, TTBF was associated with presenting PSA (p < 0.001), Gleason score (p < 0.01), and (for the NAD + RT data set) T stage (p < 0.001), but not pre-NAD Hb (p = 0.24) or pre-RT Hb (p > 0.3). CONCLUSION: Hemoglobin level is not an important determinant of RT outcome in localized prostate cancer. 相似文献
998.
999.
The effect on the fetus of medications used to treat pregnant inflammatory bowel-disease patients 总被引:5,自引:0,他引:5
Moskovitz DN Bodian C Chapman ML Marion JF Rubin PH Scherl E Present DH 《The American journal of gastroenterology》2004,99(4):656-661
OBJECTIVES: We reviewed data to investigate the effect of 5-ASA drugs, metronidazole, ciprofloxacin, prednisone, 6-mercaptopurine, azathioprine, and cyclosporine on pregnancy outcomes in patients with inflammatory bowel disease (IBD). METHODS: One hundred and thirteen female patients with a total of 207 documented conceptions were studied. Treatment information included: smoking history (patient and spouse), dates of conception and termination, and outcome of pregnancy (spontaneous abortion, therapeutic abortion, maternal or fetal illness resulting in abortion, premature birth, healthy full-term birth, multiple births, ectopic pregnancy, congenital defects), weight of baby, type of delivery (cesarian section, vaginal), medication history during each trimester (mean dose, maximum dose, frequency). We analyzed the effect on pregnancy outcome of medication use during the first trimester or at any time during the pregnancy. RESULTS: Thirty-nine patients (34.5%) had ulcerative colitis (UC), 73 (64.5%) had crohn's disease (CD), and 1 patient (1%) had indeterminate colitis. For 100 of the 207 conceptions, the patients were on 5-ASA drugs at some time during the pregnancy, 49 on prednisone, 101 on an immunomodulator (6-MP/azathioprine), 27 on metronidazole, 18 on ciprofloxacin, and 2 on cyclosporine. In 85 (31%) of the conceptions, patients were on none of these medications. No significant differences were found among the groups in each pregnancy with respect to outcome (p values 0.091 to 0.9). In multivariate analyses controlling for age of mother, there was no evidence that 5-ASA type drugs or any type of drug influenced pregnancy outcome. CONCLUSIONS: In 113 female patients with 207 conceptions none of the drugs used to treat IBD is associated with poor pregnancy outcomes. 相似文献
1000.
Corwin ND 《Annals of internal medicine》2004,140(9):763; author reply 763