全文获取类型
收费全文 | 1271篇 |
免费 | 119篇 |
国内免费 | 22篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 41篇 |
妇产科学 | 12篇 |
基础医学 | 63篇 |
口腔科学 | 120篇 |
临床医学 | 86篇 |
内科学 | 128篇 |
皮肤病学 | 14篇 |
神经病学 | 71篇 |
特种医学 | 12篇 |
外科学 | 37篇 |
综合类 | 102篇 |
现状与发展 | 1篇 |
预防医学 | 580篇 |
眼科学 | 10篇 |
药学 | 52篇 |
1篇 | |
中国医学 | 11篇 |
肿瘤学 | 65篇 |
出版年
2024年 | 3篇 |
2023年 | 18篇 |
2022年 | 82篇 |
2021年 | 118篇 |
2020年 | 56篇 |
2019年 | 45篇 |
2018年 | 42篇 |
2017年 | 43篇 |
2016年 | 39篇 |
2015年 | 40篇 |
2014年 | 84篇 |
2013年 | 118篇 |
2012年 | 74篇 |
2011年 | 77篇 |
2010年 | 47篇 |
2009年 | 40篇 |
2008年 | 56篇 |
2007年 | 49篇 |
2006年 | 48篇 |
2005年 | 39篇 |
2004年 | 27篇 |
2003年 | 29篇 |
2002年 | 19篇 |
2001年 | 20篇 |
2000年 | 17篇 |
1999年 | 14篇 |
1998年 | 20篇 |
1997年 | 9篇 |
1996年 | 13篇 |
1995年 | 9篇 |
1994年 | 11篇 |
1993年 | 10篇 |
1992年 | 13篇 |
1991年 | 6篇 |
1990年 | 12篇 |
1989年 | 6篇 |
1988年 | 7篇 |
1987年 | 8篇 |
1986年 | 1篇 |
1985年 | 8篇 |
1984年 | 4篇 |
1983年 | 3篇 |
1982年 | 5篇 |
1981年 | 6篇 |
1980年 | 6篇 |
1979年 | 3篇 |
1978年 | 1篇 |
1976年 | 2篇 |
1975年 | 4篇 |
1971年 | 1篇 |
排序方式: 共有1412条查询结果,搜索用时 15 毫秒
41.
A. R. A. L. Rossini C. L. Hashimoto K. Iriya C. Zerbini E. R. Baba J. P. P. Moraes-Filho 《Diseases of the esophagus》2008,21(4):316-321
SUMMARY. Patients with primary head and neck cancers have a higher risk of developing esophageal cancer. The aim of this study was to investigate esophageal cancer prevalence, its risk factors (ethanol and tobacco consumption) and dietary habits in patients with head and neck cancer. Three hundred and twenty-six adults with primary head and neck cancer were followed by a retrospective observational study in a general university hospital in Sao Paulo, Brazil. Flexible videoendoscopy with lugol chromoscopy was the method used to investigate esophageal cancer prevalence. All subjects were interviewed face-to-face, revealing detailed information about their tobacco and alcohol use, as well as their dietary habits. Thirty-six patients with esophageal cancer were diagnosed and the overall prevalence rate was 11.04%. Patients who developed second esophageal tumors had the following characteristics: earlier age of initial ethanol consumption ( P < 0.05), longer duration period of ethanol consumption ( P < 0.05) and higher weekly consumption rate ( P < 0.05). There was an increased risk of esophageal carcinoma in those patients who both smoked and drank ( P < 0.05). There was no association between carcinoma of the esophagus and dietary habits in patients who developed esophageal neoplasms, compared with those who did not. Prevalence rate of esophageal neoplasms was 11.04% in patients with head and neck carcinoma, whose ethanol consumption was associated with esophageal cancer. There was an increased risk between ethanol and tobacco consumption and esophageal carcinoma development. On the other hand, there was no association regarding dietary habits between patients who developed esophageal cancer and those who did not. 相似文献
42.
Pucciani F Boni D Perna F Bassotti G Bellini M 《Diseases of the colon and rectum》2005,48(11):2094-2099
PURPOSE This retrospective study evaluates the effect of abdominal hysterectomy on patients affected by descending perineum syndrome.
METHODS Eighty-nine female patients affected by descending perineum syndrome and one group of 10 healthy women with normal bowel habits
were studied retrospectively. Thirty-two descending perineum syndrome patients (Group 1) had received an abdominal hysterectomy
for benign diseases, while 57 descending perineum syndrome patients (Group 2) had not undergone this surgery. All 99 subjects
underwent clinical evaluation, computerized anorectal manometry, and defecography.
RESULTS Dyschezia was found predominantly in Group 2 subjects (P < 0.05). Fecal incontinence was significantly higher in Group 1 than in Group 2 (P < 0.05). The worst anal resting pressure was found in the incontinent Group 1 patients (P < 0.01). Rectoanal intussusception was a significant defecographic sign in Group 1 subjects (P < 0.05).
CONCLUSIONS Clinical evaluation and instrumental data suggested a possible link between fecal incontinence and abdominal hysterectomy
in patients affected by descending perineum syndrome. 相似文献
43.
《Sleep medicine》2021
Study objectivesTo examine the associations between screen time, the time spent on different screen devices, and sleep in a sample of Finnish preschool children.MethodsThe current study analyzed cross-sectional data from the DAGIS study carried out in Finland in 2015–2016 on 736 children aged 3–6 years. Parents reported in a 7-day diary the durations the child used screen devices daily, with separate details about watching TV or DVDs, using tablets or smartphones, and using computers. In addition, parents reported children's bedtimes and wake-up times, which were further used in calculating sleep duration. Parents answered questions regarding their child's sleep consistency. Statistical analyses included adjusted general linear modeling.ResultsAn hourly increase in total screen time was associated with 11 min later bedtime (p < 0.001) and 10 min shorter sleep duration (p < 0.001). More TV/DVD watching was associated with later bedtimes (p = 0.016) and a shorter sleep duration (p = 0.001). More smartphone/tablet use was associated with later bedtimes (p = 0.005), later wake-up times (p = 0.038), and weaker sleep consistency (p = 0.024). More computer use was associated with later bedtimes (p = 0.046). Results did not differ between genders.ConclusionsIncreased screen time was associated with later bedtimes and shorter sleep duration among preschool children. Adverse associations with sleep outcomes were found for each screen device. Attention should be paid to promoting balanced use of screens and regular sleep habits in young children. 相似文献
44.
《Sleep medicine》2021
ObjectiveTo determine the differences between sleep habits and circadian preference in school-aged children attending a Mexican double-shift school system.MethodsThis cross-sectional study consisted of 400 elementary public-school children (mean age = 10.77, SD = 0.70 y, from fourth, fifth and sixth grades) in Reynosa, Tamaulipas, in northeastern Mexico. Attending a double-shift school system: 200 from the morning shift and 200 in the afternoon shift. Specific questions regarding sleep habits were collected and for circadian preference, the Morningness-Eveningness Scale for Children (MESC) was used.ResultsMultivariate analysis reported no sex differences. Children attending at the morning shift during weekdays rose earlier, reported shorter time in bed and earlier midpoint of sleep than those in the afternoon shift. On weekends, morning shift children went to bed later than afternoon shift. Morning shift reported greater social jetlag, shorter average sleep length and more sleep deficit than afternoon shift. During weekdays and weekends evening type children went to bed later, rose later and reported later midpoint of sleep. Also, evening type reported more social jetlag than morning types.ConclusionThis study suggests that early school start times can have a detrimental effect on Mexican children. Moreover, the morning shift children may be at more risk of poor health due to the higher social jetlag, as well as a higher tendency to be sleep deprived. On the other hand, the afternoon shift represents an important social environment that allows children to follow their natural physiological needs and a more optimal sleep health. 相似文献
45.
《Sleep medicine》2021
Study objectivesTo investigate circadian typology in a large, representative sample of Norwegian adolescents, and its implications for sleep health.MethodsThe sample included 3920 1st year high school students aged 16–17 years. Respondents completed a web-based survey, including the short version of the Horne-Ostberg Morningness-Eveningness Questionnaire (rMEQ), the Munich Chronotype Questionnaire (MCTQ) and items on sleep-related behaviors (eg electronic media usage in bed, consumption of caffeinated beverages), sleep beliefs and daytime sleepiness. Data were analyzed using one-way ANOVAs and Chi-squared tests.ResultsIn all, 7.8% were categorized as morning, 52.3% as intermediate and 39.9% as evening types, respectively. Evening types had later sleep timing, longer sleep latency, more social jetlag and shorter school day sleep duration than morning types, with intermediate types displaying a sleep pattern between these two extremes. None of the circadian types met the minimum recommended amount of sleep on school nights (ie 8+ hours), and only morning types had a mean sleep duration of 7+ hours (7:19 h, nearly 1 h more than evening types who slept 6:20 h, p < 0.001). Evening types reported more use of electronic media in bed, more consumption of caffeinated beverages and more daytime sleepiness than the other circadian types. They were also less satisfied with their school day sleep duration and perceived it more difficult to change their sleep pattern.ConclusionsResults from this study suggest that eveningness represents a sleep health challenge for older adolescents. 相似文献
46.
47.
Massimo Corsalini Daniela Di Venere Francesco Pettini Dorina Lauritano Massimo Petruzzi 《International journal of medical sciences》2013,10(12):1784-1789
BACKGROUND: Burning Mouth Syndrome (BMS) is a chronic disease characterized by absence of any lesions and burning of the oral mucosa associated to a sensation of dry mouth and/or taste alterations. The purpose of our study is to estimate signs and symptoms of Temporomandibular Disorders (TMD) in patients with BMS and to investigate for the existence of an association between BMS and TMD.MATERIALS AND METHODS: Forty-four BMS patients were enrolled; BMS subtype was established according to the classification of Lamey. After a gnathological evaluation, according to the protocol of the European Academy of Craniomandibular Disorders, patients were classified by RDC/TMD criteria. The data were compared and analyzed using a chi-square test to describe the existence of an association between BMS and TMD.RESULTS: 65.9% the BMS patients showed disorders classified as primary signs and symptoms of TMD according to RDC / TMD criteria, and 72.7% showed parafunctional habits. The chi-square test revealed a statistically significant association (p = 0.035) between BMS and TMD.CONCLUSION: The data suggest that there is a possible relationship not yet well understood between BMS and TMD, may be for neurophatic alterations assumed for BMS that could be also engaged in TMD pathogenesis. 相似文献
48.
Genshi Egusa Fumiyo Murakami Chikako Ito Yasuko Matsumoto Seijiro Kado Midori Okamura Hiroshi Mori Kiminori Yamane Hitoshi Hara Michio Yamakido 《Atherosclerosis》1993,100(2):249-255
To investigate the association of westernized food habits and concentrations of serum lipids in the Japanese, we studied 1200 healthy Japanese living in Hiroshima prefecture and 1483 ethnic Japanese from Hiroshima prefecture living in the Hawaii Islands and Los Angeles. The nutritional assessments were made by the same dietitians. No major difference was observed in the total energy intake between the Japanese and the Japanese-Americans in both males and females. However, the intake of animal fat and simple carbohydrates (especially fructose) were markedly greater, and that of complex carbohydrates lower, in the Japanese-Americans compared with the Japanese. The mean serum cholesterol (CH), LDL-CH and serum triglyceride (TG) levels were significantly higher in the Japanese-Americans in both sexes. The mean HDL-CH concentration was similar between the two groups in males, but it was approximately 7 mg/dl higher in Japanese-American females. Using the 75 percentile values of CH and TG in the Japanese in Hiroshima, the frequency of WHO types IIa and IIb hyperlipidemia was about twice as high in the Japanese-Americans. These results suggest that westernized food habits in the Japanese include qualitative changes in animal fat, simple carbohydrate and complex carbohydrate diet rather than an increase in the total energy intake. These changes are associated with marked increases in the concentrations of serum CH and TG and increased prevalence of types IIa and IIb hyperlipidemia. 相似文献
49.
A. Maugeri S. Kunzova J.R. Medina-Inojosa A. Agodi M. Barchitta M. Homolka N. Kiacova H. Bauerova O. Sochor F. Lopez-Jimenez M. Vinciguerra 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2018,28(8):847-855
Background and Aims
The frequency and timing of meals may affect cardiovascular health (CVH) outcomes, but large-scale epidemiological studies are lacking. The aim of this study was to understand the relationship between eating time interval and frequency, and measures of ideal CVH in the Kardiovize Brno cohort study, a random urban sample population in Central Europe.Methods and Results
1659 members of the Kardiovize Brno 2030 cohort were included in a cross-sectional study (mean age = 46.86 years; 44.6% male). Exposure variables were eating time interval and frequency, and skipping meals. Primary outcomes were indices of CVH, including body mass index, diet, physical activity, smoking, blood pressure, glucose and cholesterol, and the composite CVH score. Cluster analysis and binary logistic regression analysis were used to evaluate eating habits and the association between variables.After adjustment for well-known risk factors, subjects who skipped breakfast or the afternoon snack had a higher risk of poor CVH (OR = 1.613; 95%CI = 1.121–2.320; p = 0.010; OR = 1.409; 95%CI = 1.110–1.788; p = 0.005, respectively). Moreover, we identified three clusters of individuals based on eating habits; from cluster 1 to cluster 3, eating time interval and frequency increased and this was associated with increases in CVH score from 8.70 (SEM = 0.10) in cluster 1, and 9.06 (SEM = 0.08) in cluster 2 to 9.42 (SEM = 0.09) in cluster 3 (p-trend = 0.019).Conclusions
Our findings suggest that skipping breakfast or the afternoon snack are risk factors for poor CVH, while higher eating time interval and frequency may promote ideal CVH. 相似文献50.
目的:了解南充市农村中老年居民膳食习惯和高血压患病的现状,探索膳食因素对高血压的影响,为倡导科学合理的膳食习惯,预防高血压,控制心血管疾病的发生发展提供科学依据。方法:对南充市蓬安县两个乡镇439名40岁以上居民进行高血压的检测和膳食行为进行问卷调查。结果:该地农村中老年居民高血压的患病率为23.9%。多因素Logistic回归分析发现,喝牛奶、吃蔬菜水果、豆制品和动物内脏是高血压发生的保护因素;饮酒、吃咸的、腌制的食物是高血压发生的主要危险因素。结论:农村中老年居民高血压的患病率较高,且存在一些不合理的膳食习惯,应开展有效的营养知识的普及及正确饮食习惯的宣传教育,倡导科学合理的膳食习惯,预防高血压等慢性疾病。 相似文献