全文获取类型
收费全文 | 5622篇 |
免费 | 439篇 |
国内免费 | 5篇 |
学科分类
医药卫生 | 6066篇 |
出版年
2023年 | 41篇 |
2022年 | 26篇 |
2021年 | 114篇 |
2020年 | 70篇 |
2019年 | 112篇 |
2018年 | 135篇 |
2017年 | 112篇 |
2016年 | 128篇 |
2015年 | 141篇 |
2014年 | 188篇 |
2013年 | 289篇 |
2012年 | 389篇 |
2011年 | 412篇 |
2010年 | 193篇 |
2009年 | 171篇 |
2008年 | 384篇 |
2007年 | 373篇 |
2006年 | 410篇 |
2005年 | 422篇 |
2004年 | 407篇 |
2003年 | 364篇 |
2002年 | 335篇 |
2001年 | 57篇 |
2000年 | 37篇 |
1999年 | 57篇 |
1998年 | 71篇 |
1997年 | 61篇 |
1996年 | 53篇 |
1995年 | 52篇 |
1994年 | 33篇 |
1993年 | 34篇 |
1992年 | 28篇 |
1991年 | 22篇 |
1990年 | 28篇 |
1989年 | 25篇 |
1988年 | 18篇 |
1987年 | 19篇 |
1986年 | 16篇 |
1985年 | 19篇 |
1984年 | 26篇 |
1983年 | 11篇 |
1982年 | 22篇 |
1981年 | 28篇 |
1980年 | 26篇 |
1979年 | 15篇 |
1978年 | 17篇 |
1976年 | 10篇 |
1975年 | 9篇 |
1974年 | 13篇 |
1973年 | 8篇 |
排序方式: 共有6066条查询结果,搜索用时 374 毫秒
1.
2.
3.
Several studies have demonstrated that a descending dopaminergic pathway innervates the dorsal and the intermediate gray matter of the spinal cord and have suggested that this pathway is involved in pain modulation and in the control of autonomie functions. Other studies have also demonstrated the presence of dopamine (DA) and DA metabolites as well as of DA receptors in the ventral cord. There is also evidence for the implication of DA in the control of motor functions at the spinal level. The occurrence of a dopaminergic innervation in the ventral horn has been, however, disputed until recently. But recent work has demonstrated that the motoneural cell groups in the ventral horn (lamina IX) are a target for descending dopaminergic fibers. In addition, the possibility that DA is a mediator of primary afferent fibers has also been postulated. Finally, the occurrence of dopaminergic cell bodies has been suggested in the spinal cord. This indicates that DA is probably implicated in a complex manner in spinal functions. In the present paper the possible involvement of DA in sensory and in motor functions at spinal level will be discussed in view of neurochemical observations made in polyarthritic rats, in which pain-related behavior and reduction of locomotor activity associated with a marked decrease in mobility, are observed. 相似文献
4.
5.
Human papillomavirus genotype distribution in low-grade cervical lesions: comparison by geographic region and with cervical cancer. 总被引:13,自引:0,他引:13
Gary M Clifford Rashida K Rana Silvia Franceschi Jennifer S Smith Gerald Gough Jeanne M Pimenta 《Cancer epidemiology, biomarkers & prevention》2005,14(5):1157-1164
Low-grade squamous intraepithelial lesions (LSIL) associated with certain human papillomavirus (HPV) genotypes may preferentially progress to cervical cancer. HPV genotyping may thus have the potential to improve the effectiveness of screening programs and to reduce overtreatment. LSIL cases (n = 8,308) from 55 published studies were included in a meta-analysis. HPV genotype distribution was assessed by geographic region and in comparison with published data on cervical squamous cell carcinoma (SCC). HPV detection in LSIL was 80% in North America but less than 70% in other regions, most likely reflecting regional differences in LSIL diagnosis. Among 5,910 HPV-positive LSILs, HPV16 was the most common genotype (26.3%) followed by HPV31 (11.5%), HPV51 (10.6%), and HPV53 (10.2%). HPV-positive LSILs from Africa were 2-fold less likely to be infected with HPV16 than those in Europe, and HPV-positive LSILs from North America were more likely to be infected with HPV18 than those from Europe or South/Central America. Interpretation for rarer genotypes was hampered by variation in HPV testing methodology. SCC/LSIL prevalence ratios indicated that HPV16 was 2-fold and HPV18 was 1.5-fold more common in SCC than in HPV-positive LSIL, thus appearing more likely to progress than other high-risk genotypes (SCC/LSIL prevalence ratios between 0.05 and 0.85). HPV53 and HPV66 showed SCC/LSIL ratios of 0.02 and 0.01, respectively. HPV genotype distribution in LSIL differs from that in cervical cancer, highlighting the importance of HPV genotype in the risk of progression from LSIL to malignancy. Some regional differences in the relative importance of HPV genotypes in LSIL were noted. 相似文献
6.
Sheela R Geraghty Barbara S Davidson Barbara B Warner Amy L Sapsford Jeanne L Ballard Betsy A List Rachel Akers Ardythe L Morrow 《Journal of human lactation》2005,21(1):59-66
Although there are well-established clinical human milk banks in the United States, there are no milk banks specifically intended to foster research on human milk. The authors' goal was to establish a milk bank with a core data set to support exploratory and hypothesis-driven studies on human milk. Donations to the Cincinnati Children's Research Human Milk Bank are accepted within the context of ongoing, hypothesis-driven research or on an ad hoc basis. Donors must give informed consent, and scientists wishing to use the samples must have Institutional review board approval for their use. Development of more research human milk banks can potentially provide resources for multidisciplinary collaboration and advance the study of human milk and lactation. 相似文献
7.
8.
9.
10.