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31.
Summary Calcified tissue in the iliac crest and the adjoining ala of the ilium was investigated by scanning electron micrographs of thick, polished sections from which the marrow had been removed. Some quantitative properties of the trabeculae and of the marrow spaces were obtained from measurements on the images of the polished surfaces. Most of the cortex of the crest was porous, about 25% void, of varying thickness, intruding into the cancellous space in some regions. A structure containing about 35% by volume of bone was found at and near the anterior superior spine. Compact bone of normal appearance began as thin medial and proximal sheets below the crest, and thickened until at 20–30 mm it was substantial. The cancellous bone contained by these structures was varied. Two main zones were distinguished, whose junction ran from just below the anterior superior spine to the lower portion of the iliac fossa. In the lateral zone, adjacent to the crest, there were arch-like structures, commencing from the medial and proximal walls, and meeting, or even crossing, near the centre. The medial zone was distinguished by large marrow cavities and strongly orientated trabeculae. The relative volume of bone was similar in the two zones, falling from a maximum of 15–20% to about 5% in the regions of the anterior inferior spine and the iliac fossa. The average width of the trabeculae was significantly greater in the medial than in the lateral zone (W b (m)0.16 mm, Wb(l)0.12 mm). Inclusions of very heavily constructed trabeculae, having average widths of about 0.35 mm, were found in both zones.  相似文献   
32.
Objective : To investigate if Chlamydia pneumoniae is present in the wall of the thoracic aorta in patients operated on for aneurysm or aortic dissection. Design : Consecutive patients undergoing surgery for thoracic aortic aneurysm (TAA, 32 patients) and for aortic dissection (6 patients) were included in this prospective study. Tissue samples from the aorta were analysed for the presence of C. pneumoniae by polymerase chain reaction (PCR), histopathology, immunohistochemistry and in one aortic tissue sample C. pneumoniae was verified by electron microscopy and immunogold labelling technique. Cultured Hep 2 cells infected with C. pneumoniae were used as a positive control for electron microscopy. Sera for microimmunofluorescence were obtained in 36/38 and throat swabs for C. pneumoniae PCR in 17/38 patients. Results : Chlamydia pneumoniae was detected by PCR in 4 of 32 TAA tissue samples (12%) and in 0 of 6 patients operated on for aortic dissection. Chlamydia pneumoniae inclusion bodies in one of the PCR positive tissue samples were verified by electron microscopy. IgG antibodies to C. pneumoniae were present in 17/31 (55%) and IgA in 15/31 (48%) of the TAA patients and in none of five tested patients with dissection. None of the tested throat swabs was positive. Conclusion : In this study we report the presence of C. pneumoniae by PCR and electron microscopy in the wall of TAA. A high prevalence of serum IgA antibodies to C. pneumoniae was found in TAA patients. In contrast no signs of C. pneumoniae were detected in patients with thoracic aortic dissection.  相似文献   
33.
34.
The purpose of this study is to compare scanning electron microscopy findings of the blister roof in three distinct bullous diseases: one intraepidermal acantholytic (pemphigus foliaceus); one due to hemidesmosomal dysfunction (bullous pemphigoid); and one secondary to anchoring fibril dysfunction - type VII collagen (dystrophic epidermolysis bullosa). In pemphigus foliaceus, acantholytic phenomena were readily demonstrated. In bullous pemphigoid, the epidermis had a solid aspect. In dystrophic epidermolysis bullosa a net was seen in the blister roof.  相似文献   
35.
Abstract

The ability of an experimental lazaroid, U74389G, to prevent damage to hippocampal CA 1 cytoarchitecture due to transient global ischemia was studied by light and electron microscopy. Post-ischemic rats were given a single i.p. dose of lazaroid (6 or 18 mg kg-1) at 5 min after revival by cardiopulmonary resuscitation (CPR). Without lazaroid treatment the number of normal-appearing neurons in the CA1 region declined from a normal value of 75.49± 2.21 to 8.40± 10.08 per 100 μ,m2 on day 7 after the ischemic episode, and there was extensive damage visible in the cytoarchitecture of this region. In lazaroid treated rats, the normal cytoarchitecture was retained and the number of normal-appearing cells was maintained at 15.1O± 2.22 per 100 ¼,m2? Ultrastructure studies indicated that pyknotic pyramidal cells laden with Pysosomal aggregates were common in untreated post-ischemic rats but rare in lazaroid-treated rats. These results indicate that U74389G maintained the structural integrity of this region of the brain after transient global ischemia and suggest that this lazaroid may be an effective neuroprotectant. [Neural Res 1997; 19: 431-434]  相似文献   
36.
本文对脱皮马勃、大马勃、紫色马勃及其伪品粗皮马勃进行了性状和显微鉴定的研究,为马勃鉴定提供了依据。  相似文献   
37.
目的通过角膜共焦显微镜(CCM)评价肌萎缩侧索硬化症患者小纤维病变情况及其诊断价值。方法肌萎缩侧索硬化症患者57例, 为2015年6月至2016年2月北京大学第三医院神经内科门诊和住院患者, 男性37例、女性20例, 年龄24~80(52±11)岁。健康对照组30名, 男性21名、女性9名, 年龄23~76(55±13)岁。采用CCM量化分析角膜神经纤维的角膜神经纤维长度(NFL), 神经分支密度(NBD), 神经纤维密度(NFD), 神经纤维弯曲度(NFT), 并同时进行接触性热痛诱发电位(CHEP), 皮肤交感反射(SSR)等检查。计量资料用xˉ±s或M(Q1, Q3)表示;计量资料符合正态分布者组间比较用t检验, 偏态分布计量资料可用秩和检验等非参数检验, 计数资料分析用χ2检验。多因素计量资料相关分析用简单相关分析。所有统计分析采用SPSS 12.0软件处理。结果肌萎缩侧索硬化症组角膜NFL、NFD均显著低于健康对照组[(12.2±4.4)mm/mm2比(15.1±4.5)mm/mm2, P=0.028;(50.8±24.0)个/mm...  相似文献   
38.
目的:采用激光共聚焦显微镜技术动态观察一株女性阴道来源卷曲乳杆菌生物膜的形成过程. 方法:使用体外盖玻片生物膜培养法,培养阴道来源卷曲乳杆菌的生物膜,在培养2、4、8、12、16、20、24、48、72、96、120 h后取出盖玻片,用异硫氰酸荧光素标记的刀豆蛋白A( fluorescein isothiocyanate-conjugatedconcanavalin A,FITC-conA)和碘化丙啶( andpropidium,PI)双重免疫荧光染色,激光共聚焦显微镜( confocal laser scanning microscopy, CLSM)观察卷曲乳杆菌生物膜形成过程与特点. 结果:获得生物膜形成过程不同时间点的CLSM图像,观察到卷曲乳杆菌在4 h即开始有散在的细菌黏附于盖玻片上,为可逆吸附期;8~20 h细菌黏附量逐渐增加,进入不可逆吸附期,20 h细菌聚集成团,生物膜初步形成;24~48 h形成大片的生物膜菌落,细菌镶嵌在大量多糖基质中,结构紧密,形态稳定,生物膜成熟;72 h后生物膜菌落开始解聚. 培养20 h乳杆菌生物膜密度为42. 7 × 10 -3 ± 6. 83 × 10 -3 ,24 h上升为102.5 ×10 -3 ±23.14 ×10 -3,两者相比差异具有统计学意义(P<0.05),表明培养24 h乳杆菌生物膜形成. 结论:该株阴道来源卷曲乳杆菌在体外可形成生物膜,24 h可形成成熟的生物膜,72 h生物膜开始解聚再定植.  相似文献   
39.
省、市、县三级实验室分别采用镜检法、胶体金法及巢式PCR法对泰安市2015-2019年输入性疟疾进行诊断与复核。共诊断与复核输入性疟疾病例122例,其中镜检法和胶体金法的符合率分别为94.3%(115/122)和95.9%(117/122),镜检阴性率为5.7%(7/122),均为恶性疟;胶体金法阴性率为4.1%(5/122),3例非恶性疟和2例恶性疟阴性,3种检验方法符合率差异有统计学意义(P <0.05)。其中恶性疟和间日疟诊断符合率最高,均达100%,对卵形疟诊断符合率最低,仅为12/18,对4种疟原虫实验室诊断符合率差异有统计学意义(P <0.01)。医疗机构中初诊合格率为94.3%(115/122),市、县级疾病预防控制机构复核合格率分别为97.5%(119/122)和95.1%(116/122),差异无统计学意义(P> 0.05)。今后应继续加强市、县级疟疾实验室镜检人员技能培训,积极开展疟疾核酸检测,以进一步提升医疗及疾病预防控制机构的疟疾诊断水平。  相似文献   
40.
Summary Intercellular adhesion molecule-1 (ICAM-1) is a membrane bound molecule that plays an important role in the pathogenic inflammatory responses observed in vasculitis. The aim of this study was to determine whether levels of soluble ICAM-1 sICAM-1) shedding into the circulation reflect the vascular injury found in nailfold capillaroscopy as well as systemic vasculitis in RA patients. We determined serum levels of sICAM-1 and soluble interleukin-2 receptor (sIL-2R) by an enzyme-linked immunosorbent assay in 79 RA patients. Serum level of sICAM-1 were significantly increased in RA patients compared to 30 healthy controls. RA patients with clinical signs of systemic vasculitis showed significantly higher levels of sICAM-1 than those without vascular involvement. Although no significant correlation between sICAM-1 levels and the capillaroscopy findings were found, 75% of the patients with severe vascular changes in capillaroscopy exceeded normal sICAM-1 cut off value. Serum sICAM-1 concentrations correlated significantly with the erythrocyte sedimentation rate and serum sIL-2R, but not with the duration of RA, radiological stages, Ritchie index, age or type of treatment. These findings suggest that increased levels of sICAM-1 in serum of RA patients reflect systemic vascular involvement rather than a local vascular injury.  相似文献   
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