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101.
目的:实验于2006-02/07在锦州医学院科学实验中心完成。将72只健康SD大鼠按随机数字表法分为假手术组、模型组、神经生长因子治疗组,每组24只。采用Logna等改良法复制大脑中动脉血栓模型,动物清醒2h后进行功能评价,动物神经功能达到2级的纳入实验。假手术组除不进行大脑中动脉线栓外,其余同模型组。神经生长因子治疗组于缺血后立即腹腔注射神经生长因子1000μg/kg,1次/d。于缺血后1,3,7,14d处死动物,运用免疫组化和免疫荧光双标的方法观察神经生长因子对脑缺血后神经干细胞巢蛋白的表达及其细胞类型的影响。结果:72只大鼠均进入结果分析。①神经生长因子治疗组和模型组大脑皮质均可见巢蛋白阳性细胞,细胞呈圆形或椭圆形。与模型组相比,除缺血后1d外,神经生长因子治疗组其他时间点的巢蛋白阳性细胞数均明显高于模型组,两组缺血后各时间点的巢蛋白阳性细胞数均高于假手术组[模型组:(3.47±0.51),(5.13±1.14),(13.95±3.56),(8.97±2.08)个;神经生长因子治疗组:(3.81±0.66),(9.88±2.08),(19.87±3.86),(26.17±2.90)个,假手术组:0,P<0.05,P<0.01]。②模型组和神经生长因子治疗组3d时缺血皮质巢蛋白阳性突起主要与胶质纤维酸性蛋白共存,14d时巢蛋白与神经元特异性烯醇化酶共存明显增多。结论:神经生长因子能增加局灶性脑缺血后巢蛋白的阳性细胞的数目,并促进其分化为神经元和神经胶质细胞。  相似文献   
102.
目的:观察针刺足三里、悬钟2穴对缺血性脑卒中脑血管功能的影响,分析其可能的作用机制,并对临床疗效做出评价。方法:选择2004-11/2006-05湖北中医药高等专科学校附属古城医院针灸科、荆州市第五人民医院中医康复科、荆州市第三人民医院中医科3单位缺血性脑卒中患者合适病例160例,采用查随机数字表的方法,将其随机分为对照组和针刺组,各80例。对照组采用现代医学常规干预方法进行治疗:卧床,保持呼吸道通畅,预防感染,控制颅内压、血压,维持水电解质平衡。针刺组在此基础上加针刺足三里、悬钟2穴,采用慢速捻转进针法针刺,留针20~30min,每隔5min行针1次。1次/d。两组患者治疗30d。并以经颅多普勒检测观察缺血性脑卒中患者治疗前后脑血管舒缩反应能力、脑血流自动调节功能、大脑半球侧枝循环代偿功能的变化,同时以治疗前后神经功能缺损程度为指标评价其临床疗效。结果:160例病例全部进入结果分析。①针刺组与治疗前相比,脑血管舒缩反应能力明显加强,差异有显著性意义(t=2.97,P<0.05),且优于对照组(t=2.45,P<0.05)。②针刺组与治疗前相比,脑血流自动调节能力明显改善,差异有非常显著性意义(t=8.01,P<0.01),且优于对照组(t=7.67,P<0.05)。③针刺组与治疗前相比,大脑半球侧枝循环代偿功能得到加强,差异有显著性意义(t=3.15,P<0.05),且优于对照组(t=5.16,P<0.05)。④针刺组与治疗前相比,神经功能缺损积分明显降低,差异有非常显著性意义(t=4.83,P<0.01),且优于对照组(t=5.43,P<0.05)。结论:针刺足三里、悬钟2穴对缺血性脑卒中患者脑血管舒缩反应能力、脑血流自动调节功能、大脑半球侧枝循环代偿功能有明显改善作用,并能促进神经功能的恢复。  相似文献   
103.
Phase I clinical trials of the purine analog 2',3'-dideoxyinosine (ddl) revealed that 10% of the patients developed pancreatitis, yet there was no clear relationship between increasing doses of ddl and the development of pancreatitis. To test the effects of chronic ddl administration on the structure and function of the rat pancreas, male Wistar rats were given ddl at 100 mg/kg/day i.p. for 35 days or 1400 mg/kg/day for 30 days, in two divided doses. Serum amylase levels, pancreatic tissue water content (edema) and pancreatic morphology by light and electron microscopic examination of pancreata from ddl-treated rats were similar to those of rats receiving saline injections only (controls). 2',3'-Dideoxyinosine administration did not alter the subcellular distribution of the lysosomal enzyme cathepsin B, whose redistribution to a more dense zymogen granule-enriched subcellular fraction is an early indicator of acute pancreatitis. Dispersed pancreatic acini from rats receiving ddl (100 mg/kg/day for 30 days) were incubated in vitro for 15 min with either caerulein or carbamylcholine as secretory stimuli. There was no detectable difference in the stimulatable amylase secretion from ddl-treated animals compared to the control group. Based on these findings, we conclude that ddl has no direct toxic effect on the rat pancreas. 2',3'-Dideoxyinosine may be contributing to pancreatitis in acquired immunodeficiency syndrome patients by potentiating other pancreatotoxic agents or by its action on a pancreas that is already altered by the human immunodeficiency virus infection.  相似文献   
104.
Although empirical evidence suggests that global hopelessness differentiates depression from anxiety, the degree to which depressed and anxious patients endorse hopelessness about specific life events has yet to be investigated. In the present study, outpatients with major depression (n = 64), outpatients with generalized anxiety disorder (n = 29), and outpatients with other psychiatric disorders (n = 56) completed the Imagined Outcome Test, in which they described the personal problem that was most distressing to them, imagined the worst and best possible outcomes, and rated the likelihood that these outcomes would actually occur. Depressed outpatients rated worst outcomes as being more likely and best outcomes as being less likely than outpatients in the other two groups. Results support the hypothesis that hopelessness about the resolution of life problems is unique to depression.  相似文献   
105.
目的:通过长骨干骨折脂肪栓塞综合征患者内固定植入物及其方式的合理选择,以最大限度减少手术创伤及减少对骨折端的刺激,有效避免脂肪栓塞综合征的复发。方法:①对象:选择1998-02/2006-03唐山市第二医院创伤科收治长骨干骨折行内固定植入的脂肪栓塞综合征患者26例。②方法:采用非扩髓髓内钉固定股骨干、胫骨干中段骨折及多段骨折、微创经皮钢板内固定股骨干远端骨折及胫骨干远近端骨折、钢板固定肱骨干、桡骨骨折;术后早期进行系统的康复治疗;并接受随访。术后定期复查X线片,并观察材料及宿主反应。结果:①术后随访:16例患者术后随访12~24个月,10例患者随访25~108个月。②X线摄片评定骨折愈合结果:长骨干骨折髓内钉固定于术后10~17周临床愈合;微创经皮钢板固定,于术后9~19周临床愈合;钢板固定,于术后13~20周临床愈合。无髓内钉松动及断钉、断板等并发症,肌力5级,未发现脂肪栓塞综合征后遗症。③植入物与组织的生物相容性能评估:术后无切口感染、局部炎症反应、排异反应。结论:对于长骨干骨折的脂肪栓塞综合征患者,非扩髓髓内钉、微创经皮钢板及钢板3种内固定植入物及植入方式均可满足不同部位及类型长骨干骨折的需要,植入物与人体具有良好的生物相容性,不增加脂肪栓塞综合征复发率及后遗症。  相似文献   
106.
目的:综述干细胞治疗糖尿病的研究现状及未来发展。资料来源:应用计算机检索Pubmed2000-01/2006-11有关干细胞治疗糖尿病方面文献,检索词“diabetes mellitus and stem cell not review”,限定文章语言种类为English。资料选择:对检索到的干细胞治疗糖尿病相关文献进行整理,选取针对性强文章。同一领域文献则选择近期发表或权威杂志文章。资料提炼:共检索到359篇相关文献,有关胚胎干细胞、胰腺干细胞、造血干细胞、神经干细胞、骨髓基质干细胞在糖尿病方面研究文章50篇,其中29篇符合要求。资料综合:干细胞极强的自我更新能力和多向分化潜能为糖尿病的细胞治疗开辟了新途径,按其发育阶段不同可以将干细胞分为胚胎干细胞和胰腺干细胞、造血干细胞、神经干细胞、骨髓基质干细胞等成体干细胞。干细胞移植是治疗糖尿病的一条新途径。干细胞生成胰岛素分泌细胞前需要经过诱导分化、细胞选择和细胞成熟3个阶段。干细胞治疗糖尿病研究已取得一定进展,部分实验已纠正糖尿病动物的高血糖状态。结论:干细胞定向分化为胰岛β细胞研究为糖尿病患者点燃了新希望,其勿庸置疑的成为治疗糖尿病的最佳种子细胞。  相似文献   
107.
目的:介绍了Bateson提出双重束缚概念的过程,阐述双重束缚概念的特征,并且论述了这一概念对心理治疗起到的积极作用以及概念本身存在的问题。资料来源:应用计算机在ProQuest数据库、EBSCOhost数据库中搜索1980-01/2006-05相关文章,检索的关键词为“doublebind”,“paradox”;在西南大学图书馆手工查找有关“双重束缚”资料。资料选择:对查找的资料进行筛选,纳入阐述双重束缚提出的历史、概念以及应用的文献。排除:①非实证研究和综述。②管理、文化和道德中双重束缚的研究。③重复性的研究。资料提炼:共收集49篇文章,选择与本文相关的28篇进行综述。另外还参考《理解人性》,《家庭治疗基础》两本书籍。资料综合:“双重束缚”是Bateson结合“再学习”和“Russellian矛盾”两个概念提出的。对“双重束缚”的各种定义均体现了这一概念的如下特征:矛盾性、命令性、不平等性、不可逃避性和长期性。“双重束缚”在心理治疗中有广泛的应用,但是各种对“双重束缚”的研究都存在着不足。结论:“双重束缚”的提出有其特定的历史背景,它对精神分裂、精神错乱的形成有一定的解释力。  相似文献   
108.
Critical for success of any gene therapy approach is the efficient packaging, effective cell specific delivery and nuclear translocation of the nucleic acid with minimal toxicity. Delivery systems utilizing a wide variety of viral vectors have traditionally been used to modify genomic DNA. However, drawbacks to the viral vectors include difficulties in large-scale production, potential contamination by wild-type viral particles and immunogenicity. Thus, efficient non-viral delivery of both plasmids for transgene expression and short oligonucleotides for modulating cellular functions has been developed. Gene therapy is now a consideration in the treatment of certain inherited and acquired genetic disorders associated with cardiovascular disease (CVD). Furthermore, many other cardiovascular conditions are potential targets for gene therapy, and advances in knowledge will increase the ability to link specific genes to a disease, resulting in the identification of further targets. With improvements in delivery and targeting, gene therapy is likely to substantially augment established and emerging therapies in reducing the global burden of cardiovascular disease.  相似文献   
109.
Impaired endothelium-dependent vasodilation (EDV) is an early marker of atherosclerosis. The aim of the present study was to investigate how meals with different fat contents influence endothelial vasodilatory function. A total of 26 young, healthy men and women aged 20-30 years ingested an ordinary Western meal [34 energy% (E%) fat, n =10], or isocaloric meals with low-fat (20 E%, n =8), or minimal-fat (3 E%, n =8) content. EDV was assessed as forearm blood flow (FBF) during local administration of 4 microg/min methacholine chloride (Mch-FBF) and endothelium-independent vasodilation as FBF during administration of 10 microg/min sodium nitroprusside (SNP-FBF) at baseline and 1 and 2 h after each meal. FBF was determined by venous occlusion plethysmography. An endothelial function index (EFI) was calculated as the Mch-FBF/SNP-FBF ratio. Both Mch-FBF and the EFI were decreased at 1 h after the 34 E% fat meal ( P <0.01 and P <0.05 respectively), but approached fasting levels after 2 h. Mch-FBF and EFI did not change significantly in the group consuming the 20 E% fat meal, but increased in the 3 E% fat group ( P <0.01 and P <0.05 compared with baseline for Mch-FBF and EFI respectively). SNP-FBF was not significantly affected by any of the meals. In conclusion, low-fat meals did not attenuate EDV, in contrast with an ordinary Western meal, which transiently impaired EDV. Our findings indicate that a dietary fat content of 20 E% or less might be beneficial to endothelial vasodilatory function.  相似文献   
110.
We are now approaching the reality of success in gene therapy as our knowledge of the genetic basis of disease continues to grow, coupled with improved delivery methods for therapeutic nucleic acid molecules. It is apparent that gene therapy can be divided into two specific and very different approaches in which gene replacement, or augmentation, is differentiated from gene repair. In fact, gene augmentation is characterized by the delivery of the coding sequence of the gene of interest in an expression cassette. In contrast, gene repair differs in that the process targets for correction of the mutation responsible for the genetic disorder. The in situ repair of a gene has many advantages over conventional replacement methods. This review will concentrate on the various strategies currently available for gene repair. The potential benefits of correction versus augmentation will be addressed and possible future developments outlined.  相似文献   
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