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71.
The stress of crowding and exposure to inescapable electric shock increased both the incidence and the severity of dental caries in rats housed in a conventional animal facility. Male Osborne-Mendel rats were inoculated intraorally with cariogenic bacteria, fed a high-sucrose diet, and housed in either a conventional or a sheltered facility. Rats in both housing conditions were subdivided into control and stress groups. At the end of the 56-day trial period, stressed rats from conventional housing had a significant increase in both incidence and severity of dental caries in comparison to their controls. In contrast, stressed rats from sheltered housing had a trend toward increased cariogenesis which reached significance in only one of five scores. These rats also failed to gain weight comparable to their controls, making it possible that stress-induced reduction in appetite partially offset stress-induced exacerbation in cariogenesis.This investigation was supported in part by the following Grants from the United States Public Health Service: CA 20093, HL 22727, and HL 07374.  相似文献   
72.
高师贫困生自我效能感与主观幸福感的特点及关系研究   总被引:2,自引:0,他引:2  
目的分析高师贫困生自我效能感、主观幸福感的特点及关系,为心理健康教育提供依据。方法采用一般自我效能感量表、生活满意度量表、快乐感量表,对218名贫困生和216名非贫困生进行测查。结果①高师贫困生生活满意度、快乐感显著低于非贫困生(t=4.811,P〈0.001;t=2.504,P〈0.05),自我效能感差异不显著。②高师贫困生自我效能感存在性别差异(t=2.117,P〈0.05),男生的自我效能感显著高于女生;生活满意度年级差异显著(F=3.547,P〈0.05),大一学生的生活满意度显著高于大二和大三学生,大二和大三之间的差异不显著。③高师贫困生自我效能感与生活满意度、快乐感呈显著正相关(r=0.349,P〈0.01;r=0.436,P〈0.01)。自我效能感水平越高,幸福感越强。结论高师贫困生主观幸福感相对较低,自我效能感与主观幸福感显著相关,通过提升自我效能感水平可以增强主观幸福感。  相似文献   
73.
A pair of monozygotic twins had similar but not identical dental anomalies. One twin had fusion of deciduous mandibular lateral incisor and canine on the left, with normal dentition on the right; the co-twin had right mandibular incisor/canine fusion, with aplasia of the lateral incisor on the left. These findings are discussed in the context of the related phenomena of situs inversus, mirror-imaging in twins, and gradients of severity of anomalies in the four copies of the mandibular developmental dental field. © 1994 Wiley-Liss, Inc.  相似文献   
74.
Little is known concerning the employment characteristics of hygienists practicing in nontraditional settings. Respondents were identified through screening (n = 38,380) a listing of the entire population of hygienists licensed in the United States. The screening identified 1,301 hygienists practicing in nontraditional settings. These hygienists were mailed comprehensive questionnaires; completed questionnaires were returned by 84.3 percent of the hygienists. Data were collected describing hygienists' reasons for seeking employment in nontraditional settings, their sources of information concerning job opportunities in nontraditional settings, benefits, and job satisfaction. The main source of information concerning employment opportunities in nontraditional settings was "word of mouth." Hygienists were motivated to seek employment in nontraditional settings primarily by a desire for a more challenging position and personal satisfaction. The hygienists were overwhelmingly satisfied with all aspects of nontraditional employment except opportunities for advancement. Respondents were found to receive standard benefits similar to those of employees in other industries.  相似文献   
75.
The effects of heat labile, high molecular weight water-soluble toxins from bacterial plaque on HL60 promyelocytic cells were examined. On gel filtration, four inhibitors of HL60 cell growth and two inhibitors of HeLa cell growth (PT1, PT2) were detected. The first and third HL60 cell inhibitors corresponded to the two HeLa cell inhibitors. The last eluted HL60 cell inhibitor (plaque leukotoxin, PL) did not inhibit HeLa cell growth. Anti-PT2 antibodies reduced the activity of enriched PT2 by 20-50%, but all other antisera tested exhibited no effect. Anti-PL antibodies detected antigens from Actinobacillus actinomycetemcomitans, although anti-A. actinomycetemcomitans and anti-Capnocytophaga sputigena antibodies did not react with plaque extract. These findings suggest that the plaque toxins examined in this study were probably not derived from these two bacteria.  相似文献   
76.
A study of caries experience and gingivitis prevalence in 6-, 9- and 12-yr-old children attending primary schools in Brisbane was undertaken in November/December 1983. Children from high socioeconomic level (SEL) schools exhibited lower dmft and DMFT scores at all ages. At age 6 yr the proportion of children with caries-free primary dentitions was for high SEL Schools 70%, for middle SEL schools 52% and for low SEL Schools 23%. At 12 yr DMFT scores were 1.8 (high), 2.1 (middle) and 3.3 (low). Similar differences in gingivitis prevalence occurred, children from high SEL schools displaying a much lower proportion of bleeding sites than those from middle and low SEL schools. For selection of children at "high risk" to gingival disease for intensive prevention programmes, an increased emphasis on probing techniques is indicated to achieve diagnostic consistency.  相似文献   
77.
The COVID-19 pandemic has significantly impacted daily activities worldwide. University students may have experienced substantial changes in daily living as a result of restrictions on university attendance. The return to normalcy may take a long time, and understanding the influence that shifts in daily routines have had on the lifestyles of university students may inform approaches to support overall well-being. We analyzed changes in the lifestyles of students enrolled at a health sciences university during the COVID-19 pandemic. This longitudinal study took place at the Faculty of Medicine and Nursing in the University of the Basque Country in Spain, and the final sample consisted of 113 nursing students, 109 medical students, and 45 physiotherapy students. Our results demonstrate changes in lifestyles of university students during the pandemic. MedDiet adherence scores and the percentage of students with high adherence increased during the pandemic. This increase was due to the increased consumption of vegetables and nuts. In terms of physical activity, the practice of moderate and intense physical activity was maintained. These results provide important information for both public health authorities and educational institutions to guide strategies to maintain the well-being of students and enhance opportunities for young adults to lead a healthy lifestyle.  相似文献   
78.
79.
Meal timing is an important consideration when assessing health. The primary outcome of this pilot study was to examine the feasibility and preliminary efficacy of early time-restricted eating (eTRE) on diet quality in a sample of college students attending a large southwestern university. Cardiometabolic indices and anthropometric measures were also obtained. The study was planned as an eight-week intervention; however, COVID-19 necessitated laboratory closures that disrupted data collection at week eight. Hence, only data obtained at week zero (baseline) and week four were viable for analysis and are presented herein. Twenty-five healthy participants were randomized to the intervention group (eTRE) which consisted of a daily 6-hour eating window or the control group (CON) which consisted of a daily 16-hour eating window. Each week, participants were permitted one day off from their respective study protocol. Seventeen participants completed all aspects of the study, and diet quality data were obtained from one additional participant (n = 18). Preliminary findings indicate that the 6-hour eTRE protocol may be beneficial for weight reduction and for reducing energy-dense foods typically consumed during the evening hours or later at night. Future research should accommodate individual preferences with regard to the initiation time of the eating window while also providing evidence-based nutrition recommendations to improve diet quality.  相似文献   
80.
重点高中生的心理状态与高考成绩的相关性研究   总被引:5,自引:1,他引:4  
目的;了解重点高中学生的心理状态与高考成绩之间的关系。方法:以398例应届生为对象,应用16PF人格测验,气质测量工具(STI,TTI)及焦虑自评量表(SAS),对考生进行测试分析,结果:文理科学生的16PF的人格特质有明显的差别,判别分析和多因素回归分析显示16PF人格特质中的Q1因素(实验性F=8.76,P<0.01),Q2因素(独立性F=8.23,P<0.01),与高考成绩呈正相关,与M因素(幻想性F=4.88,P<0.01),呈负相关;气质中的神经过程灵活性(F=8.15,P<0.01)和时间特质中的灵活性(F=12.36,P<0.01)与高才成绩呈正相关。结论:高考生的实验性,独立性高分及幻想性低分的个性特质和气质上的灵活性有助于高考成绩的发挥,学生文理科分班宜参考学生人格特质这一特点,。  相似文献   
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