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排序方式: 共有463条查询结果,搜索用时 15 毫秒
41.
Kristina Scheibe Christina Kersten Anabel Schmied Michael Vieth Tatjana Primbs Birgitta Carlé Ferdinand Knieling Jing Claussen Alexander C. Klimowicz Jie Zheng Patrick Baum Sebastian Meyer Sebastian Schürmann Oliver Friedrich Maximilian J. Waldner Timo Rath Stefan Wirtz George Kollias Clemens Neufert 《Gastroenterology》2019,156(4):1082-1097.e11
42.
Catherine M Capio Cindy HP Sit Kathlynne F Eguia Bruce Abernethy 《Pediatrics international》2014,56(4):651-653
Recent reports indicate an increasing prevalence of overweight among Filipino children. Considering the known association of physical activity (PA) with obesity, this study reports the findings of an objective monitoring of PA in a sample of Filipino children. The study also explores the relationship of PA with fundamental movement skills (FMS) proficiency. Thirty‐two children (6.54 ± 2.45 years old) wore an accelerometer for 7 days of PA monitoring and were assessed on five FMS (throw, catch, kick, run, jump). The children met the World Health Organization's recommendation of 60 min of PA per day, with more active time being accrued during weekdays than weekends. Children with greater FMS proficiency were found to spend more time in PA than those who were less skillful during weekends. Further research is recommended to examine PA and FMS proficiency associations, exploring the role of social interactions on weekends and weekdays. 相似文献
43.
目的:观察胸腰段椎弓根CT测量在椎弓根螺钉内固定中的作用,寻找一种个体化椎弓根螺钉置入的方法。方法:选择1999-02/2006-03河北工程大学附属医院收治的T12和/或L1段骨折患者59例,行螺旋CT检查及图像三维重建,重建结束后,得到胸腰段标本的三维图像,通过旋转和切割进行图像处理并测量,模拟出T11~L2的椎弓根形态,根据CT测量椎弓根的实际投照点进行调整,即横断面上椎弓根轴线与矢状位上椎弓根轴线的交点,在确定进钉点时选择下关节突为参照物,选用合适直径的螺钉进行植钉,植入螺钉后,连接棒或板系统。结果:262个椎弓根行植钉术,242个完全在椎弓根内,仅有20个螺钉穿透椎弓根皮质。术后平均随访16.1个月,均无临床并发症的发生,Frankel平均增加1.4级。术后有2例患者出现断钉(3枚),1例患者出现断棒,所植入的螺钉与机体生物相容性好,无不良反应的发生。结论:利用三维CT测量的数据辅助,严格按照个体化的椎弓根的轴线方向植钉,在置钉时应考虑到螺钉本身直径的因素,可以提高植钉的成功率。 相似文献
44.
目的:探讨综合式家庭治疗对抑郁患者及家属的效果。方法:于2002-11/2003-11选择郑州市第八人民医院符合中国精神障碍分类与诊断标准第3版抑郁症诊断标准的抑郁患者为实验对象。患者家住郑州市区并有直系亲属与其同住,无严重躯体疾病。76例自愿参加本实验,按随机数字表分为实验组与对照组。实验组男14例,女25例,平均(36±6)岁,首次发病年龄(28±7)岁,病程(5.6±5.4)年,住院次数(2.1±2.8)次,读书年限(11.2±2.4)年。对照组男13例,女24例,平均(35±6)岁,首次发病年龄(28±7)岁,病程(5.9±5.8)年,住院次数(2.2±2.6)次,读书年限(10.8±5.8)年。以上各变量两组间差异无显著性意义,具有较好的可比性。于患者住院时与实验组家属见面建立初步医患关系,但不干预住院期间的治疗。出院后实验组接受家庭治疗,对照组接受普通门诊治疗。家庭治疗是结合中国家庭心理行为特征,参考国外家庭系统模式、心理教育模式、认知行为模式等心理治疗理论发展起来的。分积极干预和维持治疗两个阶段。积极干预的疗程一般为1年半至2年,以药物治疗、心理教育、家庭干预为主要手段。采用汉密顿抑郁量表评价临床症状,用临床总体量表-疗效总评量表评定临床疗效,用修订社会功能缺陷筛选表评价患者社会功能,用修订社会功能缺陷筛选表得分百分率描述患者最近半年社会功能缺陷的严重程度(0%为最好,100%为最差),分别于入院时、出院时、随访6个月后进行评定。评价家庭负担的方法:要求关键亲属从6个方面评价疾病最近半年对家庭生活的影响程度(0:没有影响;1:轻度;2:中度;3:重度)。结果:76例患者均均进入结果分析。①两组患者入院时和出院时的汉密顿抑郁量表及临床整体量表-疗效总评估量表评分差异无显著性意义,但通过出院后24个月家庭心理治疗之后,实验组与对照组汉密顿抑郁量表及临床整体量表-疗效总评估量表评分差异有显著性意义,实验组疗效要明显好于对照组[汉密顿抑郁量表:(7.08±4.21),(12.26±0.85)分,P<0.01;临床整体量表-疗效总评估量表评分:(1.48±0.15),(2.63±0.12)分,P<0.05]。②随访期间实验组总的社会功能缺陷轻于对照组[再住院天数:(0.97±15.41),(7.61±26.14)d;全天工作时间:(86.7±48.10)%,(68.4±32.10)%;社会功能缺陷程度:(12.10±18.10)%,(38.10±15.20)%,P均<0.01]。实验组家庭随访期间受到的经济压力和情绪影响明显低于对照家庭,家属之间关系明显好于对照组[(0.78±0.61),(1.51±0.83)分;(1.76±0.52),(2.15±0.68)分;(0.43±0.69),(0.96±0.78)分,P均<0.05]。结论:综合式家庭治疗是治疗抑郁症的一个有效方法。 相似文献
45.
不同孔径纳米羟基磷灰石人工骨修复兔桡骨缺损效果比较 总被引:4,自引:7,他引:4
目的:纳米级的羟基磷灰石材料与人体内组织成分更为相似,具有更佳的生物性能。评价不同孔径的多孔纳米羟基磷灰石人工骨的骨缺损修复能力,从而筛选出适合的孔径以达到骨传导功能与生物力学性能的良好统一。方法:实验于2005-10/2006-10在深圳市第二人民医院中心实验室完成。①实验材料:纳米羟基磷灰石人工骨以硝酸钙和磷酸二氢铵为原料,采用溶胶-絮凝法制备粉体,运用压力成型、木模成型和浸渍成型分别制得孔隙分布均匀的孔径分别为50~150μm、100~250μm和300~500μm的多孔纳米羟基磷灰石人工骨。②实验动物:雄性新西兰大白兔60只随机分为植入50~150μm孔径材料组、植入100~250μm孔径材料组、植入300~500μm孔径材料组、空白对照组,每组15只。实验过程中对动物处置符合动物伦理学要求。③实验方法:制备双侧桡骨骨缺损动物模型,然后用3种不同孔径的纳米羟基磷灰石人工骨材料植入骨缺损处进行修复,空白对照组不植入任何材料。④实验评估:术后4,8和12周分别行大体标本观察、X射线片观察、扫描电镜观察及生物力学测试,比较各组材料修复骨缺损的能力。结果:实验动物均进入结果分析。①X射线片检查结果:术后4周、8周、12周,植入100~250μm孔径材料组X射线评分高于植入50~150μm,300~500μm孔径材料组,差异有显著性意义(P<0.05)。②生物力学检测结果:术后4周、8周、12周,植入100~250μm孔径材料组生物力学强度高于植入50~150μm,300~500μm孔径材料组,差异有显著性意义(P<0.05)。③扫描电镜观察结果:植入100~250μm孔径材料组成骨效果明显优于植入50~150μm,300~500μm孔径材料组和空白对照组。结论:纳米羟基磷灰石人工骨具有良好的成骨能力,但其骨修复能力受孔径因素的影响,孔径100~250μm的纳米羟基磷灰石人工骨材料成骨能力较好。 相似文献
46.
47.
Illés Z Stern JN Reddy J Waldner H Mycko MP Brosnan CF Ellmerich S Altmann DM Santambrogio L Strominger JL Kuchroo VK 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(32):11749-11754
A humanized mouse bearing the HLA-DR2 (DRA/DRB1*1501) protein associated with multiple sclerosis (MS) and the myelin basic protein (MBP) 85-99-specific HLA-DR2-restricted T cell receptor from an MS patient has been used to examine the effectiveness of modified amino acid copolymers poly(F,Y,A,K)n and poly-(V,W,A,K)n in therapy of MBP 85-99-induced experimental autoimmune encephalomyelitis (EAE) in comparison to Copolymer 1 [Copaxone, poly(Y,E,A,K)n]. The copolymers were designed to optimize binding to HLA-DR2. Vaccination, prevention, and treatment of MBP-induced EAE in the humanized mice with copolymers FYAK and VWAK ameliorated EAE more effectively than Copolymer 1, reduced the number of pathological lesions, and prevented the up-regulation of human HLA-DR on CNS microglia. Moreover, VWAK inhibited MBP 85-99-specific T cell proliferation more efficiently than either FYAK or Copolymer 1 and induced anergy of HLA-DR2-restricted transgenic T cells as its principle mechanism. In contrast, FYAK induced proliferation and a pronounced production of the antiinflammatory T helper 2 cytokines IL-4 and IL-10 from nontransgenic T cells as its principle mechanism of immunosuppression. Thus, copolymers generated by using different amino acids inhibited disease using different mechanisms to regulate T cell responses. 相似文献
48.
Barquinero J; Kiem HP; von Kalle C; Darovsky B; Goehle S; Graham T; Seidel K; Storb R; Schuening FG 《Blood》1995,85(5):1195-1201
We have studied the role of different conditioning regimens for engraftment of genetically marked hematopoietic repopulating cells in dogs. Peripheral blood (PB) and/or marrow cells collected after treatment with recombinant canine stem cell factor (rcSCF) or cyclophosphamide were transduced in a vector-containing long-term culture system. Three different vector-producing cell lines with similar viral titers were used. In two of them, the neo-containing LN vector was packaged either in the PA317 cell line with an amphotropic murine retrovirus envelope or the PG13 cell line with the gibbon ape leukemia virus (GALV) envelope. The MFG/GC vector produced in PA317 cells contained the human glucocerebrosidase gene. Nineteen dogs received either no conditioning (group A, n = 5), irradiation to both humeri with 1,000 cGy (group B, n = 5), a sublethal dose of cyclophosphamide 40 mg/kg (group C, n = 4), a sublethal dose of 200 or 300 cGy total body irradiation (TBI) (group D, n = 3), or an otherwise lethal dose of 920 cGy TBI (group E, n = 3) before intravenous (groups A, C, D, E) or intramedullary (group B) infusion of the transduced autologous hematopoietic cells. Transduction efficiency of hematopoietic cells at the time of infusion into the animals was similar among the different conditioning groups. Dogs were observed for at least 6 months. PB granulocytes were obtained at least every 3 weeks after transplant and analyzed by polymerase chain reaction for the presence of the transduced genes. The percentages of positive results in dogs more than 4 weeks after transplantation were 0% without conditioning, 5% with local irradiation, 18% with sublethal cyclophosphamide, 33% with sublethal TBI, and 17% with otherwise lethal TBI. Analyzing the influence of conditioning regimens by a generalized estimating equation (GEE) technique, which considered the use of different retrovirus vectors and the number of mononuclear cells infused as potential confounding variables, we found that engraftment of genetically marked repopulating cells was significantly improved (P < .001) in dogs receiving systemic conditioning with either otherwise lethal TBI, sublethal TBI, or sublethal cyclophosphamide compared to dogs with local irradiation only or no conditioning. Within the limitation of the experimental design, these data suggest that myeloablative or myelosuppressive conditioning improves engraftment of genetically marked hematopoietic repopulating cells. 相似文献
49.
Deletions of the cyclin-dependent kinase inhibitor genes p16INK4A and p15INK4B in non-Hodgkin's lymphomas 总被引:7,自引:0,他引:7
The tumor suppressor genes p16INK4A and p15INK4B map to the 9p21 chromosomal locus and are either homozygously deleted or mutated in a wide range of human cancer cell lines and tumors. Although chromosome 9 abnormalities have been described in non-Hodgkin's lymphomas (NHLs), to date, the mutational status of these genes has not been determined for these malignancies. A total of five cell lines and 75 NHLs were examined for homozygous deletions or point mutations in the coding regions of both the p15 and p16 genes using Southern blot and/or polymerase chain reaction-single-strand conformation polymorphism analyses. Homozygous deletions of either the p16 gene or both the p15 and p16 genes were observed in one diffuse large B-cell lymphoma cell line and two uncultured lymphomas consisting of one large B-cell and one mixed T-cell lymphoma. In contrast, point mutations were not detected in either the cell lines or lymphomas. These results indicate that the rate of alterations in the p15 and p16 genes is low for lymphomas, but loss of p16 and/or p15 may be involved in the development of some lymphomas. 相似文献
50.
In patients with inflammatory bowel disease, chronic intestinal inflammation severely increases the risk for cancer development. In fact, various aspects of inflammation such as oxidative stress, cyclooxygenases and proinflammatory cytokines have been shown to support many aspects of cancer growth. During recent years, various experimental studies have increased our understanding of the molecular mechanisms leading to colitis-associated cancer. In particular, cytokines such as TNF-α or IL-6, which are involved in the pathogenesis of inflammation and cancer development, could be promising targets for the molecular prevention of colitis-associated cancer. 相似文献