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31.
微量元素锌、铜、硒对胎盘镉转运的影响   总被引:1,自引:0,他引:1  
目的:评价微量元素锌、铜、硒对胎盘镉转运的影响。方法:于2002年11月至2003年1月选择湖北省大冶市的待产孕妇,进行问卷调查和体格检查,同时检测全血锌、铜、硒和镉水平。采集新生儿脐血和胎盘标本用于测定镉含量。分析孕妇锌、铜、硒的营养状况是否与胎盘镉转运存在显著关联。结果:47例20~34岁孕妇全血镉(μg/L)为0.8~25.2,新生儿脐血镉(μg/L)为0.020~1.48,孕妇血镉显著高于脐血镉(T=564P<0.01)。孕妇胎盘组织镉含量(μg/g干重)为0.082~3.97。多因素线性回归分析显示,低血铜孕妇与血铜水平正常者相比新生儿脐血镉显著增加,低血锌孕妇的胎盘镉显著高于血锌正常者,低血硒孕妇的胎盘镉显著低于血硒正常者。结论:微量元素铜、锌、硒可能影响胎盘镉转运。  相似文献   
32.
0~6岁儿童骨密度与血清锌、铜、血铅关系的研究   总被引:12,自引:0,他引:12  
【目的】 探讨 0~ 6岁儿童低骨密度与血清锌、铜、血铅的关系 ,为临床儿童低骨密度的预防提供依据。 【方法】 在本院儿保门诊 ,随机抽取己排除影响骨代谢性疾病的 0~ 6岁儿童 2 0 4名 ,用超声骨密度仪测胫骨中段骨密度 ,根据同年龄、同性别骨密度值的百分位数分成低骨密度组与正常对照组 ,同时测定血清锌、铜及全血铅。 【结果】 低骨密度组平均血清锌水平 ( 12 70 .5± 14 6.0 ) μmol/L低于对照组 ( 13 2 2 .1± 166.0 ) μmol/L ,差异有显著性(P <0 .0 5 ) ;锌缺乏患病率 ( 3 0 %)高于对照组 ( 18%) ,差异有显著性 (P <0 .0 5 ) ;低骨密度组平均血清铜值 ( 14 98.6±2 16.8) μmol/L ,稍低于对照组 ( 15 3 4.4± 2 3 0 .6) μmol/L ,但差异无显著性 (P >0 .0 5 ) ;两组铜缺乏患病率、血铅值、铅中毒患病率差异无统计学意义 (P >0 .0 5 )。 【结论】  0~ 6岁儿童低骨密度的发生与锌缺乏有关 ,应加强儿童锌缺乏症的预防和治疗 ,以降低儿童低骨密度的发生。  相似文献   
33.
目的观察联合补充钙、镁、锌、铜及维生素D对中老年妇女骨密度和骨钙索的影响,以及改善骨症状的效果。方法依据人选和排除标准,在上海地区筛选出中老年妇女230人,随机分成干预组和对照组,各组再分为未绝经与绝经组。干预组A:未绝经妇女75名;对照组A:未绝经妇女40名;干预组B:已绝经妇女78名;对照组B:已绝经妇女37名。干预组每日服用2片钙尔奇添佳片(每片含钙273.5mg、VitD1.62μg、镁99.7mg、锌3.08mg、铜0.51mg),干预6个月后再进一步分成低剂量亚组和高剂量亚组,每日服用2或3片钙尔奇添佳片,再干预6个月,总计干预12个月。所有入选者在研究前后各阶段检测腰椎骨密度(BMD)及血清骨钙素(BGP),并进行24小时膳食回顾调查和记录骨症状改善情况。结果(1)骨密度:研究6个月后,干预组腰椎骨密度值较前无显著差异(P〉0.05)。研究12个月后,未绝经干预组骨密度显著增加,未绝经对照组腰椎骨密度则呈显著性下降,但已绝经干预组和对照组的骨密度研究前后无显著变化(P〉0.05)。不同剂量干预亚组骨密度间无显著差异(P〉0.05)。(2)骨钙素:研究6及12个月后各组骨钙素水平均明显降低(P〈0.05);但干预组血清骨钙素水平均明显高于对照组,差异有显著性(P〈0.05)。不同剂量干预亚组的血清骨钙素浓度间无显著差异(P〉0.05)。(3)骨症状:干预后能明显改善局部关节痛和腰背痛等骨症状。结论联合补充钙、镁、锌、铜及维生素D可明显增加未绝经妇女的骨密度和骨钙索,有效改善骨症状;并可明显改善已绝经妇女骨钙素及骨症状,但骨密度改善不明显。低剂量亚组与高剂量亚组的骨质疏松防治效果问无显著性差异。建议中老年妇女尽早补充与骨营养有关的营养素以防治骨质丢失。  相似文献   
34.
Developing a better method for the metallization of silicon solar cells is integral part of realizing superior efficiency. Currently, contact realization using screen printing is the leading technology in the silicon based photovoltaic industry, as it is simple and fast. However, the problem with metallization of this kind is that it has a lower aspect ratio and higher contact resistance, which limits solar cell efficiency. The mounting cost of silver pastes and decreasing silicon wafer thicknesses encourages silicon solar cell manufacturers to develop fresh metallization techniques involving a lower quantity of silver usage and not relying pressing process of screen printing. In recent times nickel/copper (Ni/Cu) based metal plating has emerged as a metallization method that may solve these issues. This paper offers a detailed review and understanding of a Ni/Cu based plating technique for silicon solar cells. The formation of a Ni seed layer by adopting various deposition techniques and a Cu conducting layer using a light induced plating (LIP) process are appraised. Unlike screen-printed metallization, a step involving patterning is crucial for opening the masking layer. Consequently, experimental procedures involving patterning methods are also explicated. Lastly, the issues of adhesion, back ground plating, process complexity and reliability for industrial applications are also addressed.  相似文献   
35.
Purpose: The aim of this study was to examine the feasibility of using nanoparticle-enhanced transmission ultrasound (NETUS) as an image-based monitoring modality for microwave hyperthermia treatment.

Methods: A dedicated transmission ultrasound imaging system was used to obtain acoustic projections and ultrasound computed tomography images. Initially, speed-of-sound based images were used to non-invasively monitor temperature changes in in vitro and ex vivo specimens, induced by a microwave needle-type applicator. Next, the hyperthermia acceleration ability of two ultrasound nanoparticles based contrast agents (iron oxide and copper oxide) was examined and visualised. Finally, a two-step image guided microwave therapeutic procedure using NETUS was investigated in a realistic breast mimicking phantom. First, the pathology simulating region borders were detected. Then, a microwave-induced temperature elevation was non-invasively monitored.

Results: The transmission ultrasound scanning system was able to detect temperature changes with a resolution of less than 0.5?°C, both in vitro and ex vivo. In accordance with previous studies, it was visually demonstrated that iron oxide nanoparticles expedite the heating process (p?Conclusions: NETUS can combine enhanced target visualisation with non-invasive thermometry and accelerated heating effect. Quantitative feedback, however, requires a tissue-specific calibration-curve. A proof of concept for microwave hyperthermia treatment monitoring using NETUS was established. The suggested methodology may potentially provide a non-invasive cost-effective means for monitoring thermal treatment of the breast.  相似文献   
36.
Wilson's disease (WD) is an autosomal‐recessive disorder of impaired copper metabolism resulting in accumulation of copper primarily in the liver but ultimately in many organs and tissues. A small number of patients with WD initially present with fulminant hepatic failure (FHF), hypercupremia, and intravascular hemolysis. The therapeutic goals for these patients include quickly removing the copper and preparing the patient for liver transplantation. Here, we report on a 6‐year‐old male with WD in FHF with anemia, renal insufficiency, and coagulopathy. The patient received a series of therapeutic plasma exchanges (TPE) as adjunctive therapy to remove copper and stabilize his coagulopathy and anemia until a transplant was possible. A total of five single plasma volume (1500 mL) TPE were performed over the course of 11 days with plasma as the replacement fluid. Laboratory results demonstrated temporary improvement after each procedure. Liver transplantation was performed 12 days after beginning TPE and 35 days after admission to the hospital. TPE was a successful adjunctive therapy to bridge this patient with WD to transplantation. J. Clin. Apheresis 27:282–286, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
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Abstract:  One of the targets of modern plant physiology is to identify tools for improving seed germination and plant growth under unfavorable environmental conditions. Seeds of Brassica oleracea rubrum were pretreated with melatonin at concentrations: 1, 10, and 100 μ m using a hydropriming method. Air-dried seeds of each experimental variants that were nonpretreated (control), hydroprimed (H) or hydroprimed with melatonin (HM1, HM10, and HM100) were germinated in darkness for 3 days at 25°C. Young seedlings were then transferred to the light and grown for an additional 5 days. Both germination and growth tests were performed in water and in CuSO4 water solutions in concentrations of 0.5 and 1 m m . H, HM1 and HM10 improved seed germination both in water and in the presence of Cu2+. One or 10 μ m melatonin eliminated the inhibitory effect of the 0.5 m m metal concentration on the fresh weight of seedlings. HM100 had a negative effect; thus seed germination was lower and seedlings had poor establishment. The toxic effect of Cu2+ manifested by membrane peroxidation and DNA endoreplication blocking in the seedlings grown from nontreated (control) and H seeds was not observed in the seedlings grown from HM1 and HM10 seeds; in contrast, HM100 enhanced the toxic effect of Cu2+.  相似文献   
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