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排序方式: 共有618条查询结果,搜索用时 15 毫秒
61.
Georgios P. Stathopoulos Georgios S. Stergiou Despina N. Perrea-Kostarelis Ismene A. Dontas Basil G. Karamanos Panayiotis E. Karayiannacos 《Acta oncologica (Stockholm, Sweden)》1995,34(2):253-256
The effect of the cytotoxic drug 5-fluorouracil (5-FU) on plasma lipid levels was studied in patients and animals. Seven patients with metastatic carcinoma of the colon and three with advanced breast cancer were treated with 5-FU monotherapy by i.v. push at a dose of 500 mg/m2/d for 3-5 consecutive days. The animal group comprised 9 rabbits treated with 5-FU by i.v. push at 12-18 mg/kg/d for 2 consecutive days. Measurements of serum lipid levels were performed before and 2 and 4 weeks after 5-FU administration. No obvious change of diet, body weight and bowel habits occurred during the study period. A significant reduction of total plasma cholesterol was observed in both patients and animals. The triglyceride levels were also reduced in the rabbits. Maximal cholesterol-lowering effect was observed in patients and rabbits with higher baseline cholesterol levels. The results suggest that 5-FU might interfere with lipid metabolism. 相似文献
62.
63.
测定了Gemini表面活性剂在pH值为10.86,NaBr浓度为1.0mol/L的溶液气/液界面上的表面压一分子面积的等温线。用自制的Brewster角显微镜(BAM)观察了由Gemini表面活性剂在界面上所形成单分子膜的微区形貌随表面压的变化。结果表明:当pH值为10.86时,Gemini表面活性剂在1.0mol/L NaBr溶液的气/液界面上生成了凝聚态的单分子膜;当表面压较低时,观察到在界面上形成了同心圆结构;随着表面压的增加,这些同心圆可发生聚并而形成多中心结构。 相似文献
64.
Papillary adenoma of the prostatic urethra: Report of two cases 总被引:1,自引:0,他引:1
MUSTAFA ÖZGÜR TAN YAKUP KORDAN NUR DENZ ÖZLEM ERDEM LKER EN BRAHM BOZKIRLI 《International journal of urology》2003,10(8):459-462
Papillary adenoma of the prostatic urethra is a rare cause of hematuria, hemospermia and lower urinary tract obstruction, especially in young adults. We report two cases of papillary adenoma and their endoscopic views. One of the patients had a lesion located on the verumontanum and presented with hematuria, hemospermia and symptoms of lower urinary tract obstruction. The other patient had papillary lesions located in the paramontanal gutter and presented with persistent painless hematuria. The origin of both lesions was proven to be prostatic epithelial differentiation using immunohistochemical identification of prostate-specific antigen. Papillary adenoma is believed to be benign, therefore, both lesions were carefully excised and fulgurated transurethrally. 相似文献
65.
目的 探讨双探头SPECT心肌灌注显像时位移伪影的影像特征和识别方法。方法 将心脏模型置于检查床上,与受检患者的心脏方向一致。在图像采集过程中,模型依次沿相当于患者左右、头尾和前后方向分别在不同起始点、对不同帧数作一定距离的位移。结果位移伪影的共同特点是表现为室壁放射性分布不均匀,“热区”与“冷区”交替出现,在短轴上最早出现,且表现最为明显;伪影进一步发展会在水平长轴和垂直长轴上表现为心尖附近放射性稀疏或缺损,出现与相邻室壁伴行且形态相近的“伴影”。结论位移伪影主要表现为室壁放射性分布不均,“热区”与“冷区”交替出现,在短轴图像上易于早期发现。 相似文献
66.
In this investigation, we studied the importance of cellular glutathione (GSH) in the hexose monophosphate shunt (HMPS) activity of unstimulated human erythrocytes and the mechanism by which pyruvate stimulates the HMPS. The rate of HMPS activity was measured by the production of radioactive CO2 from 14C-1-glucose or 14C-1-ribose using a vibrating reed electrometer and ionization chamber. HMPS activity was not significantly impaired by N-ethylmaleimide (NEM) in concentrations which bound all red cell GSH. Red cells incubated under carbon monoxide (CO), an experimental condition which eliminates peroxide production, still had HMPS activity which was 44% of the value under air. Pyruvate stimulation of the HMPS was unaffected by doses of NEM which bound all cellular GSH or by incubation under CO. These data indicated that pyruvate stimulation of the HMPS occurs by pathways which do not involve peroxide formation, GSH, or oxygen. This study indicates that sulfhydryl blockade of GSH does not necessarily inhibit HMPS activity and that HMPS activity in red cells may respond to reactions not linked directly to glutathione reduction. 相似文献
67.
Epstein AL; Samoszuk M; Stathopoulos E; Naeve GS; Clevenger CV; Weil S; Marder RJ 《Blood》1987,70(4):1124-1130
A monoclonal antibody, designated BM-1, which is reactive in B5 formalin-fixed, paraffin-embedded tissues, has been generated against a cytoplasmic and nuclear antigen expressed in human myeloid precursor cells and derived leukemias. Using the avidin-biotin-complex immunoperoxidase procedure, BM-1 was found to stain selectively myeloid precursor cells in normal bone marrow and mature granulocytes in the blood. In a screen of 26 normal adult and fetal human organs fixed in B5 formalin, BM-1 was negative in all nonhematopoietic tissues with the exception of tissue granulocytes and scattered cells in the peripheral cortex of the thymus. Likewise a screen of 30 solid tumor cell lines including a spectrum of carcinomas, sarcomas, and neural-derived tumors was negative. BM-1 was also negative with 21 T and B cell lymphomas and 11 Hodgkin's disease tumors. A preliminary study of tumors of the hematopoietic system revealed that BM-1 was reactive with M2 and M3 acute myelogenous leukemias (AML), chronic myelogenous leukemias (CML) and myelomonocytic leukemias, and granulocytic sarcomas. M1, M4, M5, and M6 AML clot preparations were negative in this study, indicating that BM-1 may have a role in the histopathologic diagnosis of myelogenous leukemia. Myeloid leukemic cell lines HL-60, ML-2, KG1, and TPH-1-O showed BM-1 nuclear and/or cytoplasmic reactivity in a subpopulation of cells, but erythroid and lymphoid leukemias and all lymphoma cell lines were negative. Immunoperoxidase studies of a panel of fetal tissues showed BM-1 positive cells in the peripheral cortex of the thymus and portal myelopoietic regions of the liver at 18 weeks gestation. Finally, DNA-cellulose and solid phase radioimmunoassay (RIA) techniques developed in our laboratory demonstrate that the BM-1 antigenic domain is reactive only after binding to eukaryotic but not prokaryotic single- or double-stranded DNA. Immunoblot techniques using a DNA-cellulose purified protein sample revealed that BM-1 recognizes a 183 kD protein. These studies indicate that BM-1 is recognizing a myeloid-specific antigen that, because of its DNA binding characteristics, may have an important role in the differentiation of myeloid cells at the molecular level. 相似文献
68.
Alexopoulos D Toulgaridis T Davlouros P Christodoulou J Stathopoulos C Hahalis G 《International journal of cardiology》2003,87(2-3):159-166
BACKGROUND: Coronary artery calcium, detected non-invasively, correlates well with angiographically documented coronary artery disease (CAD). This study was conducted to evaluate the diagnostic efficacy of coronary artery calcium detected by digital cinefluoroscopy for CAD and assess the effects of age and sex on it. METHODS: In 242 patients who underwent coronary angiography, coronary calcium status was determined and related to angiographic findings. RESULTS: Calcium detection had a sensitivity 85%, specificity 52%, positive predictive value 92%, negative predictive value 33% and diagnostic accuracy 81% for significant CAD. There was a better positive predictive value in men (95% vs. 80%) and negative predictive value in women (65% vs. 16%), while a higher sensitivity and diagnostic accuracy was found in older than in younger (90% and 86% vs. 78% and 74%). The sensitivity of the method increased with the number of the diseased vessels. CONCLUSIONS: Coronary calcium can be quite accurately detected by digital cinefluoroscopy. This, however, should be made in the context of sex and age. 相似文献
69.
目的探讨老年冠心病合并糖尿病患者经皮冠状动脉介入(PCI)置入雷帕霉素洗脱支架(SES)治疗的远期疗效。 方法回顾性随机入选2003年1月至2007年12月住院期间老年冠心病合并糖尿病患者行PCI 100例,并入选同时期100例无糖尿病的冠心病患者行PCI为对照组。随访5年,随访包括心绞痛复发、死亡、心肌梗死、卒中和再次血运重建的主要不良心脑血管事件。结果 两组支架术成功率均为100%。随访率100%,随访5年,糖尿病组与非糖尿病组术后并发症发生率(8.0%、7.0%)、卒中发生率(5%、3.0%)、心源性死亡率(0%、0%)差异无显著性(均为ρ〉0.05)。再次血运重建率(30.0%、14.0%)、非致死性心肌梗塞(6.0%、2.0%)心绞痛复发率(42%、20%)、全因死亡率(10%、2.0%)糖尿病组高于非糖尿病组;但心源性病死率均为0%。结论:老年患者选择性冠脉内置入药物洗脱支架安全,成功率高,远期疗效尚好,但糖尿病仍是远期不良预后的独立预测因素。 相似文献
70.
Zaravinos A Radojicic J Lambrou GI Volanis D Delakas D Stathopoulos EN Spandidos DA 《The Journal of urology》2012,188(2):615-623