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1.
CS_2作业工人血清脂质过氧化水平与LDH同功酶谱研究张文昌,连祥霖,张连娜,杨乃富(福建医学院劳动卫生学教研室,福州350004)结果表明,高接触水平组(浓度为10.42~46.54mg/m3或Σmg·年≥50)血清LPO含量与对照比较,显著性增高?..  相似文献   
2.
铅防护服的性能检测与分析   总被引:1,自引:0,他引:1  
铅防护服用于放射诊断与治疗中医护人员和患者的X射线防护。透视和拍片可以用于检查铅防护服裂缝、开线和破洞等破损状况。通过建立铅防护服的淘汰标准,定期检测、科学更新,保证最佳的放射安全。  相似文献   
3.
A VDD pacing system with bipolar single-pass leads, were implanted in 36 consecutive patients (average age 72 ± 2years) with high degree atrioventricular block and normal sinus node function. At implant the atrial signal amplitude was 2.6 ± 0.2mV measured by a pacing system analyser (PSA), 1.8 ± 0.1mV measured peak-to-peak from the telemetered calibrated electrogram, and 1.3 ± 0.1mV measured from the sensing threshold. At one month follow-up the peak-to-peak amplitudes (mV) of the telemetered atrial electrograms were not significantly different measured continuously during resting supine with quiet breathing (1.4 ± 0.1), sitting (1.6 ± 0.2). standing (1.5 ± 0.1), arm swinging (1.4 ± 0.2), hyperventilation (1.3 ± 0.1), Vaisalva manoeuvre (1.4 ± 0.1), and treadmill exercise (1.9 ± 0.6). The telemetered atrial electrogram amplitude and the atrial sensing threshold varied between 1.2 ± 0.09mV and 1.8 ± 0.1mV, and between 0.95 ± 0.07mV and 1.3 ± 0.01mV, respectively at 0.5, 1, 3, 6 and 12 months follow-up, but the changes were statistically nonsignificant. The Event Summary showed sensing of 98% to 99% of the atrial events at the different follow-up periods.  相似文献   
4.
Objective: To examine the relationship between ambient lead levels and blood lead levels and to explore the modifiers of the relationship between ambient lead and blood lead. Method: A cross-sectional study was conducted in two lead battery factories. Blood lead level and ambient lead concentration were measured for each participant concurrently. A structured questionnaire was administered to collect sociodemographic characteristics and occupational history. Design: Biological and personal environmental measurements of 219 lead-exposed workers were analyzed by both simple and multiple linear regression. A regression model was selected for interpretation. Results: A high correlation (r=0.62) between ambient lead (PbA) and blood lead (PbB) was observed. In addition, numerous factors, including age, sex, alcohol consumption, personal hygiene practice and type of lead exposure, were also found to influence blood lead levels. Although PbB was highly correlated with PbA, blood lead level may not be effectively lowered by reducing ambient lead level. Based on the regression coefficients, improvement of hygienic practice was more effective at lowering PbB than reducing ambient lead level. Good hygienic practice may be the preferential way to reduce lead exposure in current conditions. Conclusion: Education of correct work practice may be more important than engineering control in the developing countries to lower blood lead levels in lead battery factories. Received: 28 May 1996/Accepted: 30 August 1996  相似文献   
5.
本文研究营养性驱铅饮料的动物和人群试验。饮料与铅料动物组间比较,饮料组动物的尿、粪排铅量高,分别是对照组的1.5倍和1.1倍;血、肝、肾中含量低;体内 Zn、Cu、Fe 等微量元素基本稳定。其体重增长与对照组相一致。人群试验:试验组尿铅排出明显,试验末(2月后)仅为试验初的21.7%;血铅平均减少0.39μmol/l;血中 Hb、δ-ALAD 和尿中δ-ALA 等均恢复良好;不影响体内Zn、Cu 等微量元素,无不良反应。  相似文献   
6.
 To monitor the lead hazards in industries and to investigate the prevalence of elevated blood lead levels (BLLs) in lead-exposed workers, a lead surveillance system (PRESS-BLLs) has been established and operated in Taiwan, Republic of China, since July 1993. A cohort of lead-exposed workers who received a periodic annual health examination at 55 accredited hospital laboratories was constructed. A total of 9807 separate BLL measurements were reported to the system in 1994. The mean BLL was 15.8 μg/dl in male workers and 11.6 μg/dl in female workers. The mean BLL of lead-exposed workers was significantly (P<0.05, z-test) higher than that of the general Taiwanese population (8.6 μg/dl for males and 6.7 μg/dl for females). In addition, the BLLs of 983 (10.0%) workers exceeded the regulatory action level (40 μg/dl for males; 30 μg/dl for females). The workplaces and homes of 57% of the workers with elevated BLLs were thoroughly investigated to determine the sources of lead contamination. These actions identified the causes of elevated BLLs and set up strategies to reduce workers’ lead exposure. The establishment of this occupational lead surveillance system represents a method for monitoring of lead hazards from occupational and environmental settings to prevent lead poisoning. The information acquired from the system can help in the setting up of a priority of prevention and the development of control measures. It is also useful for further monitoring of changes in the BLLs of the lead-exposed-worker cohort. The Health Department of Taiwan can use this information to evaluate the effectiveness of current industrial hygiene practice. Subjects with elevated BLLs have been medically treated and placed on long-term follow-up for sequelae. Received: 2 September 1996/Accepted: 29 November 1996  相似文献   
7.
Although the adverse effect on pregnancy outcomes at high levels of lead exposure in the workplace has been recognized for years, there is uncertainty regarding the impact of exposure at the lower community exposure levels commonly encountered today. This review summarizes the epidemiologic literature and discusses pertinent methodologic issues and possible sources of interstudy variation. The authors conclude that prenatal lead exposure is unlikely to increase the risk of premature membrane rupture but does appear to increase the risk of preterm delivery. Whether prenatal lead exposure decreases gestational age in terms of infants is unclear. Prenatal lead exposure also appears to be associated with reduced birth weight, but results vary in relation to study design and degree of control for confounding. Adjustment for gestational age, a possible confounder of the birth weight-lead exposure association, did not yield clearer results.  相似文献   
8.
Lead poisoning in a precious metals refinery fire assayer and a routine OSHA inspection prompted an investigation of the index facility, a survey of the industry, and efforts to notify assayers of this previously unrecognized hazard. Air and blood samples were obtained at the index facility. Management personnel from all fire assay laboratories in Rhode Island and southern Massachusetts were interviewed. The industry's trade association, OSHA, NIOSH, trade unions, and the media were asked to assist in a nationwide notification effort. Assayers at the index facility had excessive exposures to lead due to an age-old, lead-based assaying method that remains the industry gold standard. Blood lead levels of the three assayers (mean 61.3 μ/dl, range 48–86 μg/dl) were considerably higher than those of 16 other refinery workers (mean 27.4 μg/dl, range 13–49 μg/dl). The industry survey revealed inadequate knowledge of both the lead hazard and the applicability of the OSHA lead standard. Notification efforts failed in large part due to economic obstacles. The notification of workers at high risk of lead exposure and the eradication of occupational lead poisoning will require greater attention to economic forces. © 1994 Wiley-Liss, Inc.  相似文献   
9.
铅是一种对全身组织有广泛亲和力的毒物,作用的基点是体内一些生物大分子(蛋白质、脂类、核酸),进而使大分子受损,影响到细胞功能.  相似文献   
10.
目的 :探讨右室心内膜永久性起搏电极植入术中 ,心尖部起搏与流入道起搏二者在术中起搏参数比较 ,以及流入道起搏电极植入方法。方法 :选择本院行永久性心脏起搏器安置术的 67例患者为研究对象 ,在右室心尖部起搏电极不易固定或测试起搏参数不理想时 ,改为右室流入道起搏 (12例 )。结果 :①右室心尖部及流入道两种位置起搏阈值、R波振幅、心肌阻抗比较无显著性差异 ;②术后随访 2~ 14个月两组病例均未发生电极脱位、感知异常、膈肌收缩。结论 :①右室流入道起搏与心尖部起搏一样是电极植入的有效部位 ;②右室流入道起搏与心尖部起搏一样心室电极植入技术简单易行  相似文献   
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