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71.
P53 overexpression in colorectal metastases confined to the liver and outcome of liver resection 总被引:2,自引:0,他引:2
Heisterkamp J van Bommel J Hop WC Tilanus HW Zondervan PE IJzermans JN 《Hepato-gastroenterology》1999,46(30):3109-3114
BACKGROUND/AIMS: The results of hepatic surgery for colorectal metastases are distorted by the high incidence of recurrence, despite an apparently radical resection. Selection of high-risk patients is a mandatory step towards effective application of neo-adjuvant chemotherapy. In this study, expression of the tumor suppresser gene p53 in colorectal liver metastases was correlated with recurrence after resection. METHODOLOGY: In a retrospective case-series p53 expression was assessed using standard immunohistochemical methods in the paraffin-embedded specimens of 45 liver resections for colorectal metastases, performed in 43 patients in a single institution between '86 and '96. Hospital and office charts were reviewed and follow-up was completed with a General Physicians' questionnaire in October '97. Relapse-free and cancer-specific survival from diagnosis of hepatic metastases were assessed and compared for p53+ and p53- groups. RESULTS: Median survival was 36 months with an estimated 5-year cancer-specific survival of 43% (95% confidence interval 35%-51%). Relapse-free and cancer-specific survival were not significantly different between p53+ (n = 24, 53%) and p53- (n = 21) groups (P = 0.86 and P = 0.91 respectively). P53 expression was not associated with other potential predictors, which were not of predictive value either. CONCLUSIONS: Patients at risk for recurrent disease following partial hepatectomy for colorectal metastases cannot be identified by p53 expression. 相似文献
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In a preterm infant, chest tubes were inserted for treatment of bilateral pneumothoraces. Hemorrhagic pericardial effusion with cardiac tamponade developed, probably resulting from traumatic injury by the left chest tube. The infant survived due to timely diagnostic and therapeutic intervention. No recurrence of pericardial effusion was seen and follow-up showed normal psychomotor development. 相似文献
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Edo O. Schraa Sylvia N. Schotman Marcel Scheringa Mohamed R. Daha Richard L. Marquet Jan N.M. IJzermans 《Xenotransplantation》1996,3(4):321-327
Abstract: Discordant grafting, the best alternative for future transplantation, is hampered by hyperacute rejection (HAR). Yet, there might be a difference in susceptibility to HAR between organs. In allogeneic transplantation the liver is less sensitive to antibody mediated rejection. In order to investigate whether this might also occur in discordant xenotransplantation, we performed orthotopic liver transplantation (OLT) from Dunkin Hartley guinea pigs (GP) to Brown Norway rats. Five groups were studied. In group 1, untreated controls survived for 1.5 to 4.5 hr (n = 5). In order to investigate how long a recipient could survive without a functioning graft, animals in group 2 underwent total hepatectomy (tHx) with portal-caval shunt, resulting in survival times ranging from 2 to 7 hr (n = 5). Antibody reduction by splenectomy (Spx) on day -5 (group 3) did not increase survival time (1 to 2 hr, n = 5). Complement depletion by cobra venom factor (CVF) prolonged the survival time up to 35 hr (n = 7, group 4). One animal lived for 4 days. The combined treatment of Spx and CVF resulted in similar survival times as following CVF alone, ranging from 2 hr to 6 days (n = 6, group 5). Surprisingly, none of the grafts in either of the groups showed classical signs of hyperacute rejection, like hemorrhage, edema, or obstruction of capillaries and veins as seen in the GP to rat heart transplantation model. Also liver enzyme parameters indicated no ongoing rejection. Immunohistochemistry revealed deposits of complement factors C1q, C3, and C6 on Kupffer cells but not on endothelial cells. These results indicate that, in this particular discordant model, the liver is not affected by the classical features of HAR. The beneficial effect of CVF on recipient survival therefore may rather be due to inhibition of a lethal secondary response evoked by the graft than to inhibition of HAR. 相似文献
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Synthesized and directly acquired spin-echo images were compared in order to assess the validity of magnetic resonance (MR) image synthesis as a method enabling retrospective formation of images by interactive manipulation of scan parameters. Synthetic images subjectively compared favorably in both accuracy and precision with acquired images when formed for the same values of echo (TE) and repetition times (TR) and for interpolated and extrapolated values of both TE and TR. Plots of synthetic and acquired signals within the same pixel sectors quantitatively showed comparable values for several regions of interest in the brain. Percent error and noise-normalized differences between acquired and synthetic images were tested as a quantitative measure of accuracy. Percent error was consistently less than 5% for brain parenchyma, and synthetic signals were accurate to within four times the noise level at acquisition. The apparent signal-to-noise ratio of synthetic images was comparable, superior, or inferior to similar acquired images, depending on the values of TE and TR. Total acquisition time required for synthetic formation of images for arbitrary values of TE and TR was equivalent to that of a single direct acquisition with a TR of 2,500 msec. 相似文献
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Ocular complications of orbital venography 总被引:1,自引:0,他引:1