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61.
放线瑞香宁碱的解热镇痛作用   总被引:1,自引:0,他引:1  
洪庚辛  滕忠  覃文才  韦宝伟 《药学学报》1988,23(10):779-782
从青藤科植物黑吹风(Illigera sp)总生物碱中分离出一个单体,经化学鉴定命名为放线瑞香宁碱(actinodapbnine简称Ac)。分子式C_(18)H_(17)NO_4,为10-甲氧基-1,2-(次甲二氧基)-6-去甲阿朴菲-9-醇(图1)。动物实验表明,Ac具有解痉、镇痛、局麻及降低小鼠体温等作用,并证明其镇痛作用系非中枢性。本文进一步研究其镇痛作用和对不同动物正常  相似文献   
62.
目的:比较师范院校贫困新生与非贫困新生的心理健康状况。方法:于2005-10在衡阳师范学院完成调查。采用整群抽样横断面调查方法,以衡阳师范学院2005级3089名新生为调查对象,运用症状自评量表对其进行集体测查。在统一指导语下,学生根据最近1周内的自我感觉答题,独立完成,当场收卷。结果数据运用光电阅读机(OMR2000)输入计算机心理测评工具箱标准版V3.0系统进行总分和因子分的统计。量表中没有回答的项目记为"没有",5个以上项目未答者视为问卷无效以及总分低于95分的问卷因缺乏可靠性均不进行分析。所有数据输入电脑后用SPSS11.0软件进行统计分析;群体差异比较用t和Z检验。结果:共发放3089份问卷,收回有效答卷2994份,有效率为96.92%,其中贫困新生有效答卷510份,占17.03%。问卷结果显示,师范院校贫困新生在人际关系、偏执和精神病性3项因子上的得分分别为1.86±0.54,1.70±0.48和1.58±0.43,明显高于非贫困新生(1.78±0.51,1.65±0.46,1.53±0.39,t=3.34,2.02,2.92,P<0.05)。从阳性因子的人数比率来看,师范院校贫困新生在总分阳性的人数比率为0.28,明显低于非贫困新生(0.33,Z=-2.27,P<0.05);而在人际关系、偏执和精神病性3项因子阳性的人数比率分别为0.35,0.30,0.16,明显高于非贫困新生(0.31,0.24,0.13,Z=1.73,2.72,1.71,P<0.05)。结论:师范院校贫困新生的整体心理健康状况并不比非贫困新生差,但是在人际关系敏感、偏执和精神病性3个问题上明显比非贫困新生要严重。  相似文献   
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PURPOSE: To prospectively examine the outcomes of excluded abdominal aortic aneurysms (AAA) that continue to expand without evidence of endoleak. METHODS: From 1984 to 1998, 1218 patients underwent operative retroperitoneal exclusion of AAA and aortoiliac reconstructions. During the procedure, the aneurysm sac was ligated proximally, as well as distally, which created an ideal in-vivo model of excluded AAA sacs with or without endoleaks. From January 2002 to June 2003, 15 of these patients were identified as having an increase in AAA sac size with or without an endoleak on duplex ultrasonography. These patients were prospectively evaluated by computed tomography and diagnostic arteriography. Patients with a demonstrable endoleak underwent embolization, and the remainder underwent open surgical exploration. RESULTS: Eight patients had arteriographically demonstrated endoleaks that were treated with coil embolization. The remaining 7 patients (6 men; mean age 76 years, range 68-81) without a demonstrable endoleak underwent elective surgical exploration and sac endoaneurysmorrhaphy. The mean time interval between the original surgery and aneurysm sac exploration was 76 months (range 52-92); during this time, the mean aneurysm sac size increased by 2.7 cm (range 1.3-5.2). The mean sac pressure was 53 mmHg, and the sac walls were noticeably thickened, with markedly dilated vasa vasorum. The sac contained yellow, fibrinous material with clear serous fluid (5 patients without any evidence of retrograde flow) or liquefied thrombus with serosanguinous fluid (2 patients with retrograde flow from lumbar arteries). No AAA sacs were pulsatile. CONCLUSIONS: Continued expansion of excluded AAA sacs can occur from causes other than a missed endoleak. Exudation of fluid from thickened sac wall and vasa vasorum, as well as local enzymatic activity, might lead to the formation of a sac hygroma. Furthermore, these findings raise questions as to the need for surgical exploration of all patients with an enlarging AAA sac in the setting of low sac pressures and no definable endoleak.  相似文献   
66.
Recently, elevated titers of antibody to HTLV I have been demonstrated in patients with tropical spastic paraparesis and multiple sclerosis. We evaluated the possible role of human retroviruses HTLV I and III in Canadian patients with multiple sclerosis and chronic idiopathic myelopathy. Using sensitive enzyme immunoassays, we were unable to find antibody to either HTLV I or III in 201 patients with multiple sclerosis, 29 patients with chronic myelopathy, 51 patients with other neurological disorders, or 29 normal subjects. These data do not support a role for these viruses in the cause of sporadic multiple sclerosis and chronic myelopathy in a regionally based Canadian population, but do not exclude a role for other antigenically distinct retroviruses.  相似文献   
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“Dirty-appearing white matter” (DAWM) in multiple sclerosis (MS) is defined as a region(s) with ill-defined borders of intermediate signal intensity between that of normal-appearing white matter (NAWM) and that of plaque on T2-weighted and proton density imaging. To delineate the histopathology of DAWM, four formalin-fixed cerebral hemisphere slices of three MS patients with DAWM were scanned with T2- weighted and proton density sequences. The myelin water fraction (MWF) was obtained by expressing the short T2 component as a fraction of the total T2 distribution. Hemispheric sections were then stained with Luxol fast blue (LFB) for myelin phospholipids, for myelin basic protein (MBP) and 2’,3’-cyclic nucleotide 3’-phosphohydrolase (CNP) for myelin; Bielschowsky silver impregnation for axons; and for glial fibrillary acidic protein (GFAP) for astrocytes. Compared to NAWM, DAWM showed reduction in MWF, corresponding to a reduction of LFB staining. DAWM also showed reduced Bielschowsky staining. Quantitatively, the change in MWF in DAWM most consistently correlated with the change in LFB staining. The findings of this preliminary study suggest that DAWM is characterized by loss of myelin phospholipids, detected by the short T2 component, and axonal reduction. † Deceased  相似文献   
69.
Neuropsychological performance in patients with mild multiple sclerosis   总被引:2,自引:0,他引:2  
Although changes in cognitive function in patients with multiple sclerosis (MS) have been reported, these changes have been traditionally associated with the later stages of the disease. In the current study, a comprehensive neuropsychological battery was administered to MS patients (N = 86) in whom the disease progression was relatively mild and in remission and a demographically well-matched control group (N = 46). Besides the expected differences in tests of motor function, the two groups also differed on a number of cognitive tests with no motor demands. The two cognitive functions that appear impaired were learning and memory. Given that similar deficits have been found in MS patients with more severe symptoms, it is argued that changes in cognitive function can occur in the mild stages of the disease.  相似文献   
70.
目的:由于技术原理的限制,目前尚不能对所有的HLA等位基因进行严格的区分,特别是以往没有发现的新基因序列只能通过测序的方法解决,然而,当遇到等位基因杂合时,测序给出的结果仍然无法确认新的序列改变发生在等位基因的哪一侧,这时需要用分子生物学方法分离杂合子然后进行测序才能确定新的基因序列。采用基因克隆方法确认HLA新等位基因。 方法:实验于2006-01/05在河南省红十字血液中心HLA实验室,美国海军骨髓库HLA实验室完成。造血干细胞血样由中华骨髓库提供。采用荧光微珠HLA分型方法对中华骨髓库捐献者血样进行HLA分型检测,无法给出确切结果的摸棱两可结果标本用基因克隆(TOPO TA Cloning)、DNA测序的方法确认新的HLA基因序列。 结果:通过克隆分离杂合等位基因,再进行测序确认发现新的序列与B^*3709相比,出现4个核苷酸改变:1.355nt C〉A,2.363nt C〉G,3.412nt G〉A,4.477ntC〉G,而且均发生在H哺B基因外显子3(exon3)。4处改变引起氨基酸编码改变:①编码95CTC〉ATC,氨基酸改变L〉1(亮氨酸〉异亮氨酸)。②97AGC〉AGG.S〉R(丝氨酸〉精氨酸)。③114GAC〉AACD〉N(天门冬氨酸〉天冬酰胺)。(9135GCC〉GCGA=A无氨基酸改变。 结论:①新的基因序列已经在GenBnak注册,被WHO的HLA因子命名委员会得到正式命名为HLA-B^*3712基因。②基因克隆是确认HLA新基因的根本方法。  相似文献   
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