全文获取类型
收费全文 | 9573篇 |
免费 | 605篇 |
国内免费 | 249篇 |
专业分类
耳鼻咽喉 | 17篇 |
儿科学 | 175篇 |
妇产科学 | 1280篇 |
基础医学 | 1275篇 |
口腔科学 | 37篇 |
临床医学 | 596篇 |
内科学 | 1054篇 |
皮肤病学 | 116篇 |
神经病学 | 546篇 |
特种医学 | 140篇 |
外科学 | 893篇 |
综合类 | 1127篇 |
现状与发展 | 1篇 |
一般理论 | 26篇 |
预防医学 | 1513篇 |
眼科学 | 20篇 |
药学 | 894篇 |
2篇 | |
中国医学 | 326篇 |
肿瘤学 | 389篇 |
出版年
2024年 | 20篇 |
2023年 | 139篇 |
2022年 | 258篇 |
2021年 | 368篇 |
2020年 | 322篇 |
2019年 | 346篇 |
2018年 | 304篇 |
2017年 | 298篇 |
2016年 | 330篇 |
2015年 | 266篇 |
2014年 | 497篇 |
2013年 | 705篇 |
2012年 | 401篇 |
2011年 | 485篇 |
2010年 | 413篇 |
2009年 | 430篇 |
2008年 | 460篇 |
2007年 | 442篇 |
2006年 | 399篇 |
2005年 | 374篇 |
2004年 | 294篇 |
2003年 | 302篇 |
2002年 | 253篇 |
2001年 | 217篇 |
2000年 | 223篇 |
1999年 | 170篇 |
1998年 | 132篇 |
1997年 | 135篇 |
1996年 | 90篇 |
1995年 | 110篇 |
1994年 | 108篇 |
1993年 | 87篇 |
1992年 | 89篇 |
1991年 | 98篇 |
1990年 | 71篇 |
1989年 | 69篇 |
1988年 | 66篇 |
1987年 | 64篇 |
1986年 | 60篇 |
1985年 | 73篇 |
1984年 | 89篇 |
1983年 | 56篇 |
1982年 | 40篇 |
1981年 | 54篇 |
1980年 | 48篇 |
1979年 | 41篇 |
1978年 | 41篇 |
1977年 | 27篇 |
1976年 | 18篇 |
1975年 | 17篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
《Vaccine》2022,40(16):2370-2378
Porcine reproductive and respiratory syndrome virus (PRRSV) and Mycoplasma hyopneumoniae (M. hyopneumoniae, Mhp) are two of the most common pathogens involved in the porcine respiratory disease complex (PRDC) resulting in significant economic losses worldwide. Vaccination is the most effective approach to disease prevention. Since PRRSV and Mhp co-infections are very common, an efficient dual vaccine against these pathogens is required for the global swine industry. Compared with traditional vaccines, multi-epitope vaccines have several advantages, they are comparatively easy to produce and construct, are chemically stable, and do not have an infectious potential. In this study, to develop a safe and effective vaccine, B cell and T cell epitopes of PRRSV-GP5, PRRSV-M, Mhp-P46, and Mhp-P65 protein had been screened to construct a recombinant epitope protein rEP-PM that has good hydrophilicity, strong antigenicity, and high surface accessibility, and each epitope is independent and complete. After immunization in mice, rEP-PM could induce the production of high levels of antibodies, and it had good immunoreactivity with anti-rEP-PM, anti-PRRSV, and anti-Mhp antibodies. The anti-rEP-PM antibody specifically recognizes proteins from PRRSV and Mhp. Moreover, rEP-PM induced a Th1-dominant cellular immune response in mice. Our results showed that the rEP-PM protein could be a potential candidate for the development of a safe and effective multi-epitope peptide combined vaccine to control PRRSV and Mhp infections. 相似文献
2.
3.
《Anales de pediatría (Barcelona, Spain : 2003)》2020,92(4):200-207
IntroductionMore than five million children have been conceived by assisted reproductive techniques (ART) around the world. Most authors agree that there are no differences in psychomotor development in comparison to naturally conceived children. However, these results are still contradictory.ObjectiveTo determine whether children born from a cohort of ART-clinical gestations have a higher risk of suffering neurodevelopmental disorders in comparison to a control group. The potential associated ART-factors associated were also determined.Material and methodsThe study included the assessment of children up to 3 years old conceived by ART, and born from a cohort of women treated by the reproduction unit of a public hospital from May 2012 to May 2014. A simultaneous assessment was made of matched controls, by following the newborn naturally conceived after the ART-case, of the same group of maternal age, gestational age, and type of gestation.ResultsThere were 243 clinical gestations and 267 ART-newborns, of which 231 were assessed (87%). A simultaneous assessment was carried out in 208/230 controls (90%). There were no differences in neurodevelopmental disorders (global developmental delay, autism spectrum or language delay). Multivariate analysis of potential ART factors only showed an association between transfer of frozen embryos with language delay that has not been previously described.ConclusionsThere were no differences between groups after adjusting the results according to maternal age, multiple pregnancy, and other possible confounding factors, supporting that the role of these factors may be more relevant than the ART itself. The association between frozen embryo transfer and language delay has not been previously described. Thus, more studies are needed to confirm or refute this relationship. 相似文献
4.
Sierra Holland 《Sociology of health & illness》2019,41(1):52-66
Medical interactions around reproduction are increasingly extending beyond the physician's office and onto the Internet, where negotiation with medical authority occurs in complex and dynamic ways. Recently, scholars have noted the Internet's potential for creating spaces where women can dialogue with and reconstruct medical authority, yet this growing body of work is overwhelming heteronormative. This paper thus interrogates how lesbian women use the Internet to challenge, deploy, and rework medical authority around reproduction while navigating the transition to parenthood. I draw from 17 online journals authored by lesbian couples during the conception, pregnancy, and birth of their first child, each spanning between 18 months and 2 years, in order to understand how the transition process unfolds over time. I argue that lesbian couples engage with medical authority when seeking affirmation and normalisation yet discard and publicly reject the heteronormative assumptions that accompany reproductive medicine. Further, they chart a new process that I term ‘constructing queer mother‐knowledge’, in which they critique and balance knowledges from institutionalised medicine, their own bodies, and their queer communities. With this new concept, I complicate understandings of lesbian mothers‐to‐be and their interactions with medical authority as they build subversive families. 相似文献
5.
Elizabeth A. Mosley PhD MPH Amy J. Schulz PhD MPH MSW Lisa H. Harris MD PhD Barbara A. Anderson PhD 《Women & health》2020,60(7):806-820
ABSTRACT Abortion is legal in South Africa, but negative abortion attitudes remain common and are poorly understood. We used nationally representative South African Social Attitudes Survey data to analyze abortion attitudes in the case of fetal anomaly and in the case of poverty from 2007 to 2016 (n = 20,711; ages = 16+). We measured correlations between abortion attitudes and these important predictors: religiosity, attitudes about premarital sex, attitudes about preferential hiring and promotion of women, and attitudes toward family gender roles. Abortion acceptability for poverty increased over time (b = 0.05, p < .001), but not for fetal anomaly (b = ?0.008, p = .284). Highly religious South Africans reported lower abortion acceptability in both cases (Odds Ratio (OR)anomaly = 0.85, p = .015; ORpoverty = 0.84, p = .02). Premarital sex acceptability strongly and positively predicted abortion acceptability (ORanomaly = 2.63, p < .001; ORpoverty = 2.46, p < .001). Attitudes about preferential hiring and promotion of women were not associated with abortion attitudes, but favorable attitudes about working mothers were positively associated with abortion acceptability for fetal anomaly ((ORanomaly = 1.09, p = .01; ORpoverty = 1.02, p = .641)). Results suggest negative abortion attitudes remain common in South Africa and are closely tied to religiosity, traditional ideologies about sexuality, and gender role expectations about motherhood. 相似文献
6.
Hamida Hamdi 《Andrologia》2019,51(10)
Sertraline is an antidepressant medication used extensively in the therapy of depression. The present investigation was intended to estimate the actual protective role of wheat germ oil on sertraline‐caused testicular injury in albino rats. Sertraline (human therapeutic dose, 15.63 mg/kg) was orally administrated to rats for 28 successive days. Sertraline‐administered rats were concurrently supplemented with wheat germ oil (human therapeutic dose, 68.75 mg/kg) for 28 successive days. Sertraline administration induced an elevation in testicular DNA damage and acute testicular damage illustrated by the histopathological alterations including marked degeneration and necrosis of germ cells lining seminiferous tubules, as well as interstitial oedema, congestion of interstitial blood vessel. Wheat germ oil administration potentially mitigated the histopathological alterations of sertraline‐administered rats. Lipid peroxidation, oxidative stress biomarker, showed a significant elevation in testicular tissue of sertraline‐administered rats. Furthermore, glutathione content and catalase activity were decreased in testicular tissue of sertraline‐administered rats. Serum testosterone level was elevated in sertraline‐administered rats. Wheat germ oil significantly reduced lipid peroxidation of testicular tissue and improved the antioxidant defences. Finally, wheat germ oil has a preventive role against testicular damage induced by sertraline in rats probably via its potential to prevent reactive oxygen species. 相似文献
7.
8.
N. V. Bashmakova G. N. Chistiakova I. A. Gazieva Y. M. Trapeznikova D. O. Mazurov 《Gynecological endocrinology》2015,31(10):31-33
AbstractThis study was undertaken to compare the concentrations of pro- and anti-angiogenic growth factors, nitric oxide (NO) stable metabolites in maternal serum and embryonic left ventricular (LV) isovolumic relaxation time (IRT, ms) during the first trimester in two groups of women: with pregnancy conceived by assisted reproductive technologies (ART, n?=?39) and normally conceived (control group, n?=?68) pregnancy. The concentration of vasoconstrictor endothelin 1 was 45.5 times more in ART than in control group. On the contrary, the concentrations of NO stable metabolites in ART were 1.9 times less than in control women. The assessment of angiogenic suppressors in ART women demonstrates the decrease in s-endoglin concentration was 1.6 times and in soluble receptor to vascular endothelial growth factor concentration was 2.0 times in comparison with control group. There was a significant increase in LV IRT in ART embryos in comparison to control ones. These data suggest significant changes in pro- anti-angiogenic factors balance and increase in vascular impedance in ART-conceived embryos. 相似文献
9.
ABSTRACTScreening rates for trauma are low in health care settings. We examined the association between health care providers’ (HCPs) experience of physical or sexual trauma and their screening of female patients for trauma. HCPs at an urban academic medical institution were surveyed from September through November 2016. The Brief Trauma (BTQ) and Sexual and Physical Abuse History Questionnaires (SPAHQ) assessed their own experiences of trauma. The Screening Practices Questionnaire (SPQ) assessed HCPs trauma screening. Multiple regression analyses were performed. Among 212 respondents aged 22–67 years, most were female (78.3%) and white (76.1%). Nurses (41.0%) were the largest occupational group. Overall, 85.8% reported having experienced trauma. No significant difference was observed in median SPQ scores between HCPs who had experienced trauma (3.88 [Interquartile Range (IQR) 3.44–4.31]) and those who had not (4.00 [IQR 3.47–4.33], p = .645). In an adjusted model, screening policy awareness and having an obstetrics & gynecology or psychiatry specialty were associated with higher SPQ scores (p < .001). The prevalence of trauma experience in this sample was high, but not associated with screening. Screening policy awareness and practice specialty were associated with screening. HCP factors associated with greater trauma screening should be explored. 相似文献
10.