全文获取类型
收费全文 | 39215篇 |
免费 | 3020篇 |
国内免费 | 64篇 |
专业分类
耳鼻咽喉 | 525篇 |
儿科学 | 1406篇 |
妇产科学 | 852篇 |
基础医学 | 5391篇 |
口腔科学 | 442篇 |
临床医学 | 5450篇 |
内科学 | 7431篇 |
皮肤病学 | 740篇 |
神经病学 | 4084篇 |
特种医学 | 931篇 |
外国民族医学 | 1篇 |
外科学 | 4255篇 |
综合类 | 449篇 |
现状与发展 | 1篇 |
一般理论 | 53篇 |
预防医学 | 4344篇 |
眼科学 | 678篇 |
药学 | 2368篇 |
中国医学 | 58篇 |
肿瘤学 | 2840篇 |
出版年
2023年 | 283篇 |
2022年 | 374篇 |
2021年 | 962篇 |
2020年 | 704篇 |
2019年 | 936篇 |
2018年 | 1090篇 |
2017年 | 803篇 |
2016年 | 900篇 |
2015年 | 923篇 |
2014年 | 1347篇 |
2013年 | 2008篇 |
2012年 | 2865篇 |
2011年 | 3028篇 |
2010年 | 1668篇 |
2009年 | 1424篇 |
2008年 | 2456篇 |
2007年 | 2562篇 |
2006年 | 2379篇 |
2005年 | 2373篇 |
2004年 | 2082篇 |
2003年 | 1879篇 |
2002年 | 1810篇 |
2001年 | 447篇 |
2000年 | 429篇 |
1999年 | 411篇 |
1998年 | 407篇 |
1997年 | 330篇 |
1996年 | 272篇 |
1995年 | 234篇 |
1994年 | 237篇 |
1993年 | 216篇 |
1992年 | 230篇 |
1991年 | 230篇 |
1990年 | 228篇 |
1989年 | 203篇 |
1988年 | 174篇 |
1987年 | 180篇 |
1986年 | 179篇 |
1985年 | 146篇 |
1984年 | 153篇 |
1983年 | 149篇 |
1982年 | 163篇 |
1981年 | 172篇 |
1980年 | 150篇 |
1979年 | 155篇 |
1978年 | 120篇 |
1977年 | 136篇 |
1976年 | 124篇 |
1974年 | 139篇 |
1973年 | 103篇 |
排序方式: 共有10000条查询结果,搜索用时 172 毫秒
61.
S. S. Kerwar Susan C. Ridge M. Jane Landes Joseph C. Nolan Arnold L. Oronsky 《Inflammation research》1994,43(3-4):206-210
Rabbit inflamed synovial tissue grown in culture synthesizes a factor that induces collagenase synthesis in chondrocytes and in cartilage. Synthesis of this factor by the synovial tissue is inhibited by cycloheximide but not by indomethacin. The factor has an apparent molecular weight of 30,000, is stable to heat and to trypsin treatment but is inactivated by acid. Induction of collagenase synthesis in chondrocytes occurs after a lag period of 6 hours. 相似文献
62.
63.
64.
Background: Tibialis posterior is a frequent cause of an acquired flatfoot deformity and the prevalence is not known. If tibialis posterior dysfunction was found to occur frequently, a greater awareness may result leading to earlier patient diagnosis, referral and treatment.Objectives: To validate a screening questionnaire for tibialis posterior dysfunction, and to investigate the prevalence of tibialis posterior dysfunction in a high-risk patient population.Methods: The screening questionnaire was given prospectively to 65 patients (44 females, 21 males; mean age 79.6 years) attending an unrelated care of the elderly appointment. A foot and ankle surgery fellow separately examined all feet for tibialis posterior dysfunction.Results: The survey was 100% sensitive and 98.3 % specific at detecting tibialis posterior dysfunction. Six of the 65 patients (5 females, 1 male) had tibialis posterior dysfunction, and two had bilateral involvement. All six of the patients had longstanding symptoms, all had consulted their doctor and three had seen an orthopaedic surgeon; only one of the six patients had been correctly diagnosed.Conclusions: This study suggests that tibialis posterior dysfunction occurs frequently, but is seldom diagnosed in elderly women. Further epidemiologic studies are needed to determine the true prevalence. 相似文献
65.
Kathryn E Arnold Jody L Schweitzer Barbara Wallace Monique Salter Ruth Neeman W Gary Hlady Bernard Beall 《Infection control and hospital epidemiology》2006,27(12):1377-1384
OBJECTIVE: To describe investigation of a tightly clustered outbreak of invasive group A streptococcal (GAS) disease associated with a high mortality rate in a long-term care facility (LTCF). DESIGN: Cross-sectional carriage survey and epidemiologic investigation of LTCF resident and employee cohorts. SETTING: A 104-bed community LTCF between March 1 and April 7, 2004. PATIENTS: A cohort of LTCF residents with assigned beds at the time of the outbreak. INTERVENTIONS: Reinforcement of standard infection control measures and receipt of chemoprophylaxis by GAS carriers. RESULTS: Four confirmed and 2 probable GAS cases occurred between March 16 and April 1, 2004. Four case patients died. The final case occurred during the investigation, before the patient was determined to be a GAS carrier. No case occurred during the 6 months after the intervention. Disease was caused by type emm3 GAS; 16.5% of residents and 2.4% of employees carried the outbreak strain. Disease was clustered in 1 quadrant of the LTCF and associated with nonintact skin. GAS disease or carriage was associated with having frequent personal visitors. CONCLUSIONS: Widespread carriage of a virulent GAS strain likely resulted from inadequate infection control measures. Enhanced infection control and targeted prophylaxis for GAS carriers appeared to end the outbreak. In addition to employees, regular visitors to LTCFs should be trained in hand hygiene and infection control because of the potential for extended relationships over time, leading to interaction with multiple residents, and disease transmission in such residential settings. Specific attention to prevention of skin breaks and proper wound care may prevent disease. The occurrence of a sixth case during the investigation suggests urgency in addressing severe, large, or tightly clustered outbreaks of GAS infection in LTCFs. 相似文献
66.
Julie Hicks Patrick Jenessa C. Johnson R. Turner Goins David K. Brown 《Quality of life research》2004,13(5):959-967
This study investigates functional disability among some of the nation's most vulnerable older adults: rural Medicaid recipients. Data were provided by 221 older adults (mean age = 75.9 years; 82% women) who were receiving community-based long-term care services through Medicaid. Participants self-reported functional ability involving the completion of six basic activities of daily living (BADLs), three cognitive instrumental activities of daily living (IADLS), and four physical IADLs. Self-reports of depressed affect and the number of physical health conditions were also obtained. Path analysis was used to examine all of the associations among age, gender, number of chronic health conditions, depressed affect and functional disability. The tested model was significant [chi2 (DF = 3, n = 221) = 5.052, p = 0.168; TLI = 0.945; CFI = 0.992; RMSEA = 0.056] and explained 45.1% of the variance in BADL disability. Depressed affect significantly predicted disability in cognitive IADLs and physical IADLs, which predicted disability in BADLs. Age and gender had indirect effects on BADL, through their association with cognitive IADLs and physical IADLs. The number of chronic health conditions exerted both indirect and direct effects on BADL disability. Results are discussed within the context of the growing literature that suggests the importance of psychological variables as predictors of functional disability. Moreover, we discuss whether community-based long-term care is appropriate for older adults with high levels of functional disability. 相似文献
67.
68.
The effects of glycine on the phasic changes in locomotor activity in the rat, caused by a persistent infusion of dopamine (DA) into the nucleus accumbens (ACB) were investigated. Dopamine (25 μg/24 hr), infused into the nucleus accumbens for 13 days, caused hyperactivity, with two peaks occurring on days 3–4 and 9–11. Glycine (12.5 or 25 μg/24 hr) infused into the nucleus accumbens on its own did not alter the locomotor activity, yet when infused at the same time as DA (25 μg/24 hr), glycine (12.5 or 25 μg/24 hr) inhibited the development of the first peak of hyperactivity induced by DA, with no effect on the second peak. A larger dose of glycine (50 μg/24 hr), infused alone, significantly increased locomotor activity, and a combination of this dose with DA (25 μg/24 hr), led to a temporal shift in the response to DA such that the first peak of hyperactivity was delayed to “fuse” with the second peak. The locomotor response to a threshold dose of DA (6.25 μg/24 hr) plus glycine (50 μg/24 hr) was no greater than could be accounted for by the hyperactivity response to glycine alone (50 μg/24 hr). Strychnine (10 μg/24 hr), infused into the nucleus accumbens, produced no alteration in locomotor activity. Similarly, when infused together with DA (25 μg/24 hr), strychnine (10 μg/24 hr) caused no significant alteration in the phasic hyperactivity induced by DA. However, strychnine (10 μg/24 hr), infused together with DA and glycine (25 and 12.5 μg/24 hr respectively), prevented the inhibition by glycine of the first peak of hyperactivity induced by DA. The results indicate that while glycine may not normally exert a tonic modulatory influence on those mechanisms in the nucleus accumbens which regulate locomotor activity, when applied exogenously glycine can partially moderate the locomotor response to DA, through an action on strychnine-sensitive receptors. 相似文献
69.
R W Arnold G B Stickler W M Bourne J F Mellinger 《Journal of pediatric ophthalmology and strabismus》1987,24(3):151-155
A case with ocular (corneal crystals and retinal pigment epithelial mottling), muscle (oropharyngeal and hand weakness and atrophy), and renal (proteinuria and hypertension) abnormalities is described. We believe that this represents a previously unrecognized syndrome. 相似文献
70.