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排序方式: 共有357条查询结果,搜索用时 31 毫秒
1.
联合抗青光眼手术治疗不易控制眼压青光眼的研究   总被引:1,自引:0,他引:1  
采用板层下巩膜床双咬切、睫状体剥离合并睛状体上腔植入硅橡胶条的抗青光眼联合手术治疗不易控制眼压的青光眼46例52眼,其中继发性青光眼27眼,原发闭角青光眼10眼,原发开角青光眼6眼,先天、青少年型青光眼7眼,虹膜角膜内皮综合征2眼。手术总有效率达94%。本术式具有小梁切除、睫状体剥离、睫状体扁平部引流的功能。作者认为用硅橡胶条作植入物,比异体或自体组织作植入物更为理想。  相似文献   
2.
粮谷尘致肺损害的实验研究   总被引:2,自引:1,他引:1  
粮谷尘为混合性粉尘,含游离SiO29.77%,分离培养出普通高温放线菌。染尘动物肺脏早期病变主要为小灶性肺泡炎、灶性间质性肺炎、异物肉芽肿等,大、中支气管壁脱颗粒肥大细胞增多。90d以后,上述病变明显减少,但逐渐出现少数小的细胞结节,间质轻度纤维组织增生、支气管慢性炎症和小叶中央型肺气肿样病变,观察1a(年)未见明显纤维化。  相似文献   
3.
隆鼻硅胶假体雕刻中的四个角度   总被引:1,自引:0,他引:1  
目的探讨隆鼻硅胶假体雕刻中的四个角度与隆鼻并发症的关系。方法总结了420例硅胶假体隆鼻术患者,分析并发症与假体雕刻的关系,提出假体雕刻要与鼻部解剖形态相吻合的四个角度。结果术后1周,发现3例患者假体鼻根部向一侧轻度偏斜,2例6个月后鼻根部假体固定不良。1例术后主诉头痛,取出假体后症状消失。其余未发生并发症。结论假体雕刻与鼻部解剖形态的四个角度相吻合,可以减少并发症的发生,提高美容效果。  相似文献   
4.
OBJECTIVES: This study evaluated the effect of three different surface conditioning methods on the bond strength of a Bis-GMA based luting cement to six commercial dental ceramics. METHODS: Six disc shaped ceramic specimens (glass ceramics, glass infiltrated alumina, glass infiltrated zirconium dioxide reinforced alumina) were used for each test group yielding a total number of 216 specimens. The specimens in each group were randomly assigned to one of the each following treatment conditions: (1) hydrofluoric acid etching, (2) airborne particle abrasion, (3) tribochemical silica coating. The resin composite luting cement was bonded to the conditioned and silanized ceramics using polyethylene molds. All specimens were tested at dry and thermocycled (6.000, 5-55 degrees C, 30 s) conditions. The shear bond strength of luting cement to ceramics was measured in a universal testing machine (1 mm/min). RESULTS: In dry conditions, acid etched glass ceramics exhibited significantly higher results (26.4-29.4 MPa) than those of glass infiltrated alumina ceramics (5.3-18.1 MPa) or zirconium dioxide (8.1 MPa) (ANOVA, P<0.001). Silica coating with silanization increased the bond strength significantly for high-alumina ceramics (8.5-21.8 MPa) and glass infiltrated zirconium dioxide ceramic (17.4 MPa) compared to that of airborne particle abrasion (ANOVA, P<0.001). Thermocycling decreased the bond strengths significantly after all of the conditioning methods tested. SIGNIFICANCE: Bond strengths of the luting cement tested on the dental ceramics following surface conditioning methods varied in accordance with the ceramic types. Hydrofluoric acid gel was effective mostly on the ceramics having glassy matrix in their structures. Roughening the ceramic surfaces with air particle abrasion provided higher bond strengths for high-alumina ceramics and the values increased more significantly after silica coating/silanization.  相似文献   
5.
染矽尘大鼠早期肺组织肿瘤坏死因子的表达   总被引:3,自引:1,他引:3  
目的采用组织芯片和图像分析技术阐述染矽尘大鼠早期肺组织炎性损伤过程中肿瘤坏死因子-α(TNFα)表达的变化规律。方法采用气管暴露法建立矽肺动物模型。免疫组织化学链霉菌抗生物素蛋白-过氧化物酶法(SP)结合组织芯片技术检测肺组织TNFα的表达。用ImageProPlusVersion4.5forWindowsTM图像分析系统对TNFα的表达做定量分析。结果染矽尘组TNFα阳性细胞面积百分比于染尘后第3天时开始升高,一直持续到第14天,第21天后稍有回落。第7天时达高峰,染矽尘组阳性面积百分比较对照组高出6.57,差异有显著性(P<0.01)。结论矽尘可诱导大鼠肺组织炎性损伤早期TNFα的过度表达。  相似文献   
6.
三种手段联合应用治疗瘢痕疙瘩的疗效观察   总被引:2,自引:0,他引:2  
黄方涛  卢彬 《中国医师杂志》2004,6(10):1309-1310
目的 探索治疗瘢痕疙瘩的有效方法,消除临床症状,杜绝或减少术后复发。方法 采用CO2激光清除瘢痕疙瘩。创面湿敷丹参溶液2-3周,待创面基底完全上皮化后继续在创面基底和边缘定期注射丹参注射液2-3月,同时整日敷贴硅凝胶6月。结果 治疗结束后随访1~2年,24例43块瘢痕疙瘩治愈率60.47%,显效率27.91%,总有效率88.37%。达到较满意的临床效果。结论 此方法操作简便,疗效确切,未发现副反应,但仅适合局限的瘢痕疙瘩的治疗。对面积超过15cm^2瘢痕疙瘩并未涉及。  相似文献   
7.
溶剂解吸HPLC法测定工作场所空气中硝基苯   总被引:1,自引:0,他引:1  
目的:建立硅胶管采集工作场所空气中硝基苯的液相色谱分析方法。方法:硅胶管吸附空气中硝基苯,样品经甲醇解吸,HPLC检测。结果:当空气中硝基苯浓度范围在0.67~6.67mg/m^3(参照国标PC-TWA2mg/m^3)时,方法的变异系数为0.3%,回归方程式Y=42769X+74.5,相关系数r=0.9999,检出限0.03μg/ml,以采集3L空气样品计,最低检出浓度0.02mg/m^3。平均解吸效率为98.6%,硅胶吸附8.00μg硝基苯,样品放置2周,回收率仍可达98.8%,变异系数为0.6%。在本实验条件下与苯胺类化合物有较好的分离。结论:本法可应用于工作场所空气中硝基苯浓度的检测。  相似文献   
8.
Inorganic nanoparticles such as silica particles offer many exciting possibilities for biomedical applications. However, the possible toxicity of these particles remains an issue of debate that seriously impedes their full exploitation. In the present work, commercially available fluorescent silica nanoparticles 25, 45 and 75 nm in diameter optimized for cell labelling (C-Spec® particles) are evaluated with regard to their effects on cultured cells using a novel multiparametric setup. The particles show clear concentration and size-dependent effects, where toxicity is caused by the number and total surface area of cell-associated particles. Cell-associated particles generate a short burst of oxidative stress that, next to inducing cell death, affects cell signalling and impedes cell functionality. For cell labelling purposes, 45 nm diameter silica particles were found to be optimally suited and no adverse effects were noticeable at concentrations of 50 μg ml?1 or below. At this safe concentration, the particles were found to still allow fluorescence tracking of cultured cells over longer time periods. In conclusion, the data shown here provide a suitable concentration of silica particles for fluorescent cell labelling and demonstrate that at safe levels, silica particles remain perfectly suitable for fluorescent cell studies.  相似文献   
9.
Silica and asbestos cause pneumoconioses known as silicosis and asbestosis, respectively, that are each characterized by progressive pulmonary fibrosis. While local effects of inhaled silica particles alter the function of alveolar macrophages and sequential cellular and molecular biological events, general systemic immunological effects may also evolve. One well-known health outcome associated with silica exposure/silicosis is an increase in the incidence of autoimmune disorders. In addition, while exposure to silica—in the crystalline form—has also been seen to be associated with the development of lung cancers, it remains unclear as to whether or not silicosis is a necessary condition for the elevation of silica-associated lung cancer risks. Since asbestos is a mineral silicate, it would be expected to also possess generalized immunotoxicological effects similar to those associated with silica particles. However, asbestos-exposed patients are far better known than silicotic patients for development of malignant diseases such as lung cancer and mesothelioma, and less so for the development of autoimmune disorders. With both asbestos and crystalline silica, one important dysregulatory outcome that needs to be considered is an alteration in tumor immunity that allows for silica- or asbestos- (or asbestos-associated agent)-induced tumors to survive and thrive in situ. In this review, the immunotoxicological effects of both silica and asbestos are presented and contrasted in terms of their abilities to induce immune system dysregulation that then are manifest by the onset of autoimmunity or by alterations in host-tumor immunity.  相似文献   
10.
Abstract

Background:

Brick manufacturing constitutes an important industrial sector in Egypt with considerable exposure to silica.

Objectives:

We aimed for evaluating hepatic functions in silica-exposed workers in the clay brick industry, and the possible role of matrix remodeling and immunological factors.

Methods:

A case–control study, 87 workers as exposed and 45 as control subjects. Questionnaire, clinical examination, and laboratory investigations: liver functions, matrix metalloproteinase-9, immunoglobulins G and E, and anti-liver kidney microsomal antibody.

Results:

In the exposed workers, mean levels of liver functions, matrix metalloproteinase-9 (MMP-9), and IgG and IgE were significantly higher. In the silicotic subgroup the mean level of GGT was almost twice the level in the non-silicotic subjects. Logistic regression showed that abnormal GGT and ALT were associated with production workers.

Conclusion:

Workers in the clay brick industry showed evidence of liver disease that could be related to matrix remodeling.  相似文献   
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