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101.
Yusuke Demizu Kazufumi Kagawa Yasuo Ejima Hideki Nishimura Ryohei Sasaki Toshinori Soejima Toshihiro Yanou Masakazu Shimizu Yoshiya Furusawa Yoshio Hishikawa Kazuro Sugimura 《Radiotherapy and oncology》2004,71(2):207-211
We investigated the biological effect of combining carbon-beam and X-ray in vitro. The results showed that when we employed Gray equivalent as the indication of therapeutic dose, the effects could be explained with simple additive way in the treatment plan. This fact provides important information about the combined therapy of carbon-beam and X-ray. 相似文献
102.
Effects of perioperative protease inhibitor on inflammatory cytokines and acute-phase proteins in patients with hepatic resection 总被引:35,自引:0,他引:35
Ambiru S Miyazaki M Sasada K Ito H Kimura F Nakagawa K Shimizu H Ando K Nakajima N 《Digestive surgery》2000,17(4):337-343
AIM: The objective of this study was to examine the effects of perioperative administration of ulinastatin, or urinary trypsin inhibitor (UTI), on inflammatory cytokines and acute-phase proteins induced by inflammatory cytokines in patients who had undergone hepatic resection. METHOD: Twenty patients admitted to the hospital for hepatic resection were equally randomized to one of two groups: the UTI group, those who were administered perioperative UTI, and the control group. RESULTS: The UTI group had no adverse effects from using UTI. Production of serum interleukin-6 (IL-6) tended to be attenuated in the UTI group when compared with the control group. Moreover, the UTI group had significantly decreased positive acute-phase C-reactive protein (p < 0.05) and significantly increased negative acute-phase protein prealbumin and retinol-binding protein (p < 0.05). Serum IL-6 levels significantly correlated with serum C-reactive protein levels on postoperative day 1 (r = 0.70, p < 0.01). CONCLUSION: These results suggest that perioperative administration of UTI might deserve further assessment for use in modulating acute-phase responses without adverse effects in patients who have undergone hepatic resection. 相似文献
103.
Overexpression of truncated I kappa B alpha potentiates TNF-alpha-induced apoptosis in mesangial cells 总被引:4,自引:0,他引:4
Hirahashi J Takayanagi A Hishikawa K Takase O Chikaraishi A Hayashi M Shimizu N Saruta T 《Kidney international》2000,57(3):959-968
BACKGROUND: Dysregulation of apoptosis is one of the likely underlying mechanisms of mesangial proliferative glomerulonephritis (GN), a disease in which proinflammatory cytokines exhibit a wide range of biological activities. Among them, tumor necrosis factor-alpha (TNF-alpha) induces two conflicting pathways, one leading to activation of the nuclear factor-kappa B (NF-kappa B), and the other leading to caspase-mediated apoptosis. We investigated whether or not specific inhibition of NF-kappa B affects TNF-alpha-induced apoptosis in rat mesangial cells (MCs). METHODS: To specifically inhibit NF-kappa B activation, we constructed a recombinant adenovirus vector expressing a truncated form of I kappa B alpha (AdexI kappa B delta N) that lacks the phosphorylation sites essential for the activation of NF-kappa B. Electrophoretic mobility shift assay was performed to evaluate NF-kappa B activity. Nuclear morphology was observed by staining with Hoechst-33258. DNA fragmentation was detected using an ELISA kit with an antihistone antibody. To investigate the regulation of apoptosis, we measured caspase-3 and caspase-8 activity by ELISA, and examined the Bcl-2 and Bax protein level by Western blot. RESULTS: TNF-alpha-induced NF-kappa B activation was blocked by overexpression of I kappa B delta N. Overexpression of I kappa B delta N potentiated TNF-alpha-induced apoptosis compared to mock transfection, and the potentiation was abolished by treatment with a caspase-3 inhibitor, Z-DEVD-FMK. Overexpression of I kappa B delta N augmented TNF-alpha-induced caspase-3 and caspase-8 activity, but did not affect Bcl-2 or Bax protein expression. CONCLUSION: Overexpression of I kappa B delta N potentiates TNF-alpha-induced apoptosis and augments caspase-8 and caspase-3 activity in rat MCs without changing Bcl-2 or Bax protein expression. These results suggest the potential usefulness of AdexI kappa B delta N to induce apoptosis in MCs under inflammatory conditions. 相似文献
104.
105.
Intragraft events preceding chronic renal allograft rejection in a modified tolerance protocol 总被引:3,自引:0,他引:3
BACKGROUND: Inbred miniature swine treated for 12 days with high-dose cyclosporine A develop tolerance to histocompatibility complex (MHC) class I-mismatched renal allografts. When this protocol was modified by adding thymectomy before transplant, all animals developed acute rejection. Thereafter, by day 100, one half developed chronic rejection (progression group) and the other half recovered (recovery group). This provides an excellent experimental model to identify the mechanisms of chronic rejection as well as the early changes that may predict chronic rejection. METHODS: We assessed the cellular infiltration, immune activation, humoral immunity, and cell- and antibody-mediated graft injury in the progression and the recovery groups. In addition, we also examined circulating donor reactive cytotoxic T lymphocyte (CTL) and antidonor antibody in both groups. RESULTS: From days 8 to 18 after transplantation, the two groups were indistinguishable. Both showed acute rejection with endarteritis (type II); had IgG and IgM deposition in glomeruli and small vessels; had an infiltrate with similar numbers of T cells, proliferating (PCNA+) and activated (interleukin-2 receptor+) cells; and had a similar degree of parenchymal cell apoptosis [in situ DNA nick-end labeling (TUNEL)+]. However, by days 30 to 60, the two groups could be distinguished by several intragraft features. The recovery group became tolerant and had diminished T-cell infiltration, activation and proliferation, and no detectable antibody deposition. The number of TUNEL+-injured parenchymal cells decreased. In contrast, the progression group showed persistent cell infiltration with activation and proliferation. Significantly prominent TUNEL+ apoptotic parenchymal cells in tubules, glomeruli, peritubular capillaries and arteries were seen from day 30 to day 100. Circulating donor reactive CTL and antidonor class I IgG were detected in the progression group at higher levels than in the recovery group from days 30 to 60. CONCLUSION: In tolerance-induction protocols, unstable tolerance induction is associated with the persistent immunologic activation that mediates immunologic destruction of graft parenchymal cells and chronic rejection. Certain of the described immunopathologic findings (activation, proliferation, apoptosis, and antibody deposition) may be useful in distinguishing the type of rejection, that is, whether the allograft will progress to chronic rejection or recovery. 相似文献
106.
107.
A prospective study was conducted in Takayama, Gifu, Japan, to evaluate the association between diet and the onset of menopause. A total of 1,130 female residents aged 35-54 years who were premenopausal and completed a validated semiquantitative food frequency questionnaire in 1992 were contacted by mail with a follow-up questionnaire in 1998 to update information on menopause. Onset of menopause was defined as a woman's age at the last menstrual period prior to stopping menstruation for 12 months. During the 6-year study period, 296 women experienced natural menopause. The Cox proportional hazards model was used to estimate hazard ratios of the onset of menopause after controlling for age, total energy, body mass index, years of smoking, and age at which regular menstrual cycle began. The authors found that green and yellow vegetable intake was significantly inversely associated with the 6-year incidence of menopause (hazard ratio = 0.71, 95% confidence interval: 0.54, 0.95 for the highest vs. lowest tertile of intake, p for trend = 0.02). Association of carotene intake with the incidence of menopause was of borderline significance (hazard ratio = 0.78, 95% confidence interval: 0.59, 1.04, p for trend = 0.07). 相似文献
108.
109.
目的:探讨小柴胡汤对鼠肝纤维化的抑制作用及该抑制作用与活性伊东细胞间的相互关系。方法:分别腹腔注射二甲基亚硝基胺和猪血清复制两种肝纤维化动物模型并投予小柴胡汤观察其预防与治疗作用。结果:小柴胡汤可促进肝维生素 A 含量恢复;降低肝胶原含量和明显抑制肝前α-Ⅰ型胶原的基因表达;显著减少Ⅰ、Ⅲ型胶原在肝脏沉积,明显减少。α-平滑肌原纤维阳性的伊东细胞的数目。结论:小柴胡汤可防治鼠肝纤维化的发生与发展。 相似文献
110.
Uemura H Cho M Nakagawa Y Shimizu K Yoshikawa M Kim S Hirao Y 《Hinyokika kiyo. Acta urologica Japonica》2000,46(10):745-748
MN/CA IX is considered as a carbonic anhydrase isoenzyme expressed in the normal alimentary tract in a tissue-specific manner. This antigen is activated in the majority of renal cell carcinomas (RCC) but not in the normal kidney tissues. Our previous study revealed that increase of malignant potential is related to down-regulation of MN/CA9. To investigate the mechanism of MN activation in RCC, we examined the methylation status of this gene (MN/CA9) in RCC cell lines (SKRC-1, 6, 10, 12, 14, 44, 59). Moreover, we analyzed the circulating blood of patients for the presence of RCC cells by RT-PCR, to determine whether detection of circulating RCC cells could be useful as a biomarker. CpG methylation was investigated at 7 CpG sites in the MN/CA9 5' region. Clear mRNA signals were observed in 5 cell lines (SKRC-1, 6, 10, 44, 59), e.g., MN/CA9 positive. These 5 MN-positive cell lines showed hypomethylation in the 5' region. In contrast, all CpG sites were methylated in the remaining 2 lines and 3 normal kidney tissue samples. These results suggest that hypomethylation in the 5' region may play an important role in the expression of MN/CA9 in RCC. RT-PCR analysis of blood samples from RCC patients revealed the presence of circulating MN-positive cancer cells in the blood. Although a significant correlation with tumor stage and grade was not observed, the analysis of blood samples from patients with metastases resulted in a high detection rate of 82%. These findings suggest the usefulness of MN/CA IX as a potential diagnostic marker for detection of RCC. 相似文献