全文获取类型
收费全文 | 63430篇 |
免费 | 4443篇 |
国内免费 | 994篇 |
专业分类
耳鼻咽喉 | 1037篇 |
儿科学 | 6180篇 |
妇产科学 | 834篇 |
基础医学 | 6506篇 |
口腔科学 | 1682篇 |
临床医学 | 6254篇 |
内科学 | 6901篇 |
皮肤病学 | 743篇 |
神经病学 | 12838篇 |
特种医学 | 983篇 |
外国民族医学 | 1篇 |
外科学 | 3169篇 |
综合类 | 5078篇 |
现状与发展 | 3篇 |
一般理论 | 2篇 |
预防医学 | 9828篇 |
眼科学 | 379篇 |
药学 | 4894篇 |
17篇 | |
中国医学 | 783篇 |
肿瘤学 | 755篇 |
出版年
2024年 | 215篇 |
2023年 | 1284篇 |
2022年 | 2246篇 |
2021年 | 3130篇 |
2020年 | 2689篇 |
2019年 | 2394篇 |
2018年 | 2334篇 |
2017年 | 2403篇 |
2016年 | 2460篇 |
2015年 | 2263篇 |
2014年 | 3929篇 |
2013年 | 5272篇 |
2012年 | 3263篇 |
2011年 | 3779篇 |
2010年 | 2852篇 |
2009年 | 2975篇 |
2008年 | 3071篇 |
2007年 | 2820篇 |
2006年 | 2448篇 |
2005年 | 2044篇 |
2004年 | 1711篇 |
2003年 | 1606篇 |
2002年 | 1327篇 |
2001年 | 1066篇 |
2000年 | 881篇 |
1999年 | 760篇 |
1998年 | 684篇 |
1997年 | 577篇 |
1996年 | 458篇 |
1995年 | 447篇 |
1994年 | 382篇 |
1993年 | 352篇 |
1992年 | 371篇 |
1991年 | 289篇 |
1990年 | 270篇 |
1989年 | 230篇 |
1988年 | 262篇 |
1987年 | 208篇 |
1986年 | 252篇 |
1985年 | 384篇 |
1984年 | 341篇 |
1983年 | 243篇 |
1982年 | 271篇 |
1981年 | 265篇 |
1980年 | 246篇 |
1979年 | 240篇 |
1978年 | 171篇 |
1977年 | 178篇 |
1976年 | 160篇 |
1975年 | 115篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
11.
N. R. Galloway J. Tolia C. Barber 《Documenta ophthalmologica. Advances in ophthalmology》1986,63(1):31-36
The pattern evoked electroretinogram (PERG) was investigated in 11 patients with unilateral optic nerve disease and in a series of age-matched controls. The visually evoked potential (VEP) was also measured. The PERG showed a similar reduction to the VEP in optic nerve disease. Serial studies indicate that the PERG may not be affected immediately in some instances but may show a gradual decline over several months. 相似文献
12.
13.
14.
Monica Conciatori Christopher J Stodgell Susan L Hyman Melanie O'Bara Roberto Militerni Carmela Bravaccio Simona Trillo Francesco Montecchi Cindy Schneider Raun Melmed Maurizio Elia Lori Crawford Sarah J Spence Lucianna Muscarella Vito Guarnieri Leonardo D'Agruma Alessandro Quattrone Leopoldo Zelante Daniel Rabinowitz Tiziana Pascucci Stefano Puglisi-Allegra Karl-Ludvig Reichelt Patricia M Rodier Antonio M Persico 《Neuropsychopharmacology》2004,55(4):413-419
BACKGROUND: The HOXA1 gene plays a major role in brainstem and cranial morphogenesis. The G allele of the HOXA1 A218G polymorphism has been previously found associated with autism. METHODS: We performed case-control and family-based association analyses, contrasting 127 autistic patients with 174 ethnically matched controls, and assessing for allelic transmission disequilibrium in 189 complete trios. RESULTS: A, and not G, alleles were associated with autism using both case-control (chi(2) = 8.96 and 5.71, 1 df, p <.005 and <.025 for genotypes and alleles, respectively), and family-based (transmission/disequilibrium test chi(2) = 8.80, 1 df, p <.005) association analyses. The head circumference of 31 patients carrying one or two copies of the G allele displayed significantly larger median values (95.0th vs. 82.5th percentile, p <.05) and dramatically reduced interindividual variability (p <.0001), compared with 166 patients carrying the A/A genotype. CONCLUSIONS: The HOXA1 A218G polymorphism explains approximately 5% of the variance in the head circumference of autistic patients and represents to our knowledge the first known gene variant providing sizable contributions to cranial morphology. The disease specificity of this finding is currently being investigated. Nonreplications in genetic linkage/association studies could partly stem from the dyshomogeneous distribution of an endophenotype morphologically defined by cranial circumference. 相似文献
15.
16.
Jae-Seung Paick Soo Woong Kim Seung-June Oh Ja Hyeon Ku 《International journal of urology》2007,14(8):699-703
AIM: We evaluated differences between men and women with lower urinary tract symptoms (LUTS) combined with nocturia. METHODS: A total of 71 age-matched female-male pairs (median 58, range 20-81 years) who had moderate to severe LUTS and nocturia of more than once per night were enrolled in this study. RESULTS: In the younger group (<50 years), the International Prostate Symptom Score (I-PSS) results of the sexes were not significantly different. However, although total I-PSS results in the elderly group (> or =50 years) were not significantly different, quality of life index scores for women were higher (P = 0.002). On frequency-volume (FV) charts, mean total daytime voided volume (DVV) was significantly higher in younger men than in younger women (P = 0.017), but the mean nocturnal polyuria index (NPi) for women was higher than that for men (P = 0.047). However, maximum DVV (P = 0.009), mean DVV (P < 0.0001), total DVV (P < 0.0001), and mean nocturnal urine volume (P = 0.009) were significantly higher in elderly men than in elderly women. However, numbers of daytime voids were not different. CONCLUSION: Elderly women with LUTS have lower functional bladder capacities than elderly men, as suggested by their smaller mean voided volumes. However, no significant differences were observed between numbers of daytime voids, which was probably due to the smaller total daytime voided volumes of elderly women. In addition, although NPi for younger women and nocturnal urine volume for elderly men was higher, no other differences were observed in terms of other night-time parameters. 相似文献
17.
18.
The involvement of children in research studies is historically fraught with difficulties. Experiments on children without their consent or knowledge have been carried out in the past and thus the need for stringent ethical control is undoubtedly necessary. However this paper argues that the need to protect children from unethical research has somehow become entwined in the web of secrecy that surrounds the very nature of child abuse. In the name of 'protection' are children in danger of not having their voice heard?
In the foreword to 'Listening to Children' (Alderson, 1995) Roger Singleton writes, 'much research is carried out on and about children, but seldom with children. Children themselves are often strangely silent'. This paper draws on recent literature on the institutional abuse of young people in residential care and the lack of voice that those abused in residential care have traditionally had, suggesting that their silence is not 'strange' but perhaps contrived.
This paper does not repeat the work of Alderson (1995) and make suggestions as to how research with children may best be carried out, but seeks to address the issues in relation to research with children who are in institutions. 相似文献
In the foreword to 'Listening to Children' (Alderson, 1995) Roger Singleton writes, 'much research is carried out on and about children, but seldom with children. Children themselves are often strangely silent'. This paper draws on recent literature on the institutional abuse of young people in residential care and the lack of voice that those abused in residential care have traditionally had, suggesting that their silence is not 'strange' but perhaps contrived.
This paper does not repeat the work of Alderson (1995) and make suggestions as to how research with children may best be carried out, but seeks to address the issues in relation to research with children who are in institutions. 相似文献
19.
E. Isometsa M. Heikkinen M. Henriksson M. Marttunen H. Aro J. Lonnqvist 《Acta psychiatrica Scandinavica》1997,95(4):297-305
As part of a nation-wide psychological autopsy we examined the differences in DSM-III-R mental disorders, recent life events and other characteristics between urban (n=143) and rural (n=85) completed suicides in a random sample of 229 cases from the National Suicide Prevention Project in Finland for the period 1987-1988. Psychoactive substance use disorders (48% vs. 34%), cluster B personality disorders (24% vs. 9%) and psychiatric comorbidity (66% vs. 42%) were found more commonly among urban than rural suicides. Urban suicides were also more often reported to be preceded by a recent separation (25% vs. 8%), whereas rural suicide victims tended to have lacked a close companion of the opposite sex (36% vs. 18%) and to have had physical disorders (56% vs. 40%). Overall, urban and rural suicides may vary with regard to the prevalence of some mental disorders, their comorbidity, and physical disorders, as well as the preceding life situation. This variation may also imply the need for differences in strategies for suicide prevention in each setting. 相似文献
20.
Examined are several measures currently used in the assessment of child abuse, sexual abuse, and trauma. These measures include
structured clinical interviews, self report measures, screening inventory, symptom checklist, and some measures that include
decision making properties. Issues and implications for clinical practice are explored. 相似文献