全文获取类型
收费全文 | 8018篇 |
免费 | 820篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 55篇 |
儿科学 | 133篇 |
妇产科学 | 156篇 |
基础医学 | 1198篇 |
口腔科学 | 198篇 |
临床医学 | 905篇 |
内科学 | 1672篇 |
皮肤病学 | 63篇 |
神经病学 | 954篇 |
特种医学 | 368篇 |
外科学 | 965篇 |
综合类 | 173篇 |
一般理论 | 2篇 |
预防医学 | 820篇 |
眼科学 | 264篇 |
药学 | 497篇 |
中国医学 | 7篇 |
肿瘤学 | 411篇 |
出版年
2021年 | 127篇 |
2020年 | 78篇 |
2019年 | 132篇 |
2018年 | 131篇 |
2017年 | 108篇 |
2016年 | 104篇 |
2015年 | 120篇 |
2014年 | 176篇 |
2013年 | 272篇 |
2012年 | 435篇 |
2011年 | 388篇 |
2010年 | 214篇 |
2009年 | 197篇 |
2008年 | 350篇 |
2007年 | 345篇 |
2006年 | 356篇 |
2005年 | 316篇 |
2004年 | 326篇 |
2003年 | 260篇 |
2002年 | 312篇 |
2001年 | 252篇 |
2000年 | 204篇 |
1999年 | 197篇 |
1998年 | 92篇 |
1997年 | 81篇 |
1996年 | 97篇 |
1995年 | 81篇 |
1994年 | 73篇 |
1993年 | 63篇 |
1992年 | 213篇 |
1991年 | 182篇 |
1990年 | 178篇 |
1989年 | 192篇 |
1988年 | 175篇 |
1987年 | 159篇 |
1986年 | 145篇 |
1985年 | 161篇 |
1984年 | 132篇 |
1983年 | 118篇 |
1982年 | 72篇 |
1981年 | 61篇 |
1980年 | 65篇 |
1979年 | 105篇 |
1978年 | 85篇 |
1977年 | 80篇 |
1975年 | 70篇 |
1974年 | 85篇 |
1973年 | 78篇 |
1972年 | 70篇 |
1970年 | 69篇 |
排序方式: 共有8841条查询结果,搜索用时 15 毫秒
31.
M P Slade A M Brooks W E Gillies 《Australian and New Zealand journal of ophthalmology》1989,17(4):445-450
Two cases are reported: a father and son with a new syndrome consisting of a severe congenital glaucoma associated with a form of palmoplantar keratoderma showing features of mutilating palmoplantar keratoderma. Both the glaucoma and keratoderma may be attributed to an autosomal dominantly inherited genetic mutation of a single chromosome affecting two tissues of neural crest origin, the ectodermal tissues of the hands and feet and the cranial mesenchyme from which the tissues of the chamber angle develop. Elucidation of the precise chromosomal abnormality causing these defects may help in understanding the inheritance and aetiology of glaucoma. 相似文献
32.
33.
34.
A unilateral supratentorial lesion may cause hypometabolism in the contralateral cerebellar hemisphere (crossed cerebellar diaschisis). We analyzed glucose metabolism, measured by PET-FDG, in the posterior fossa in 67 patients (78 PET studies) with primary unilateral supratentorial brain tumors selected for visually obvious metabolic asymmetry in the cerebellar hemispheres. We found that glucose utilization was 17% lower in the contralateral cerebellar cortex (compared with the ipsilateral one), consistent with the selection criterion, and 19% lower in the ipsilateral pons, wherein lie the first order synapses of the corticopontocerebellar pathway. This finding helps to validate the prevalent view that cerebellar diaschisis is due to interruption of afferent input from the corticopontocerebellar pathway. However, glucose metabolism in the contralateral dentate nucleus was relatively preserved--only 2% less than the ipsilateral dentate. This "dentate sparing" suggests preservation of afferent input to the largest of the deep cerebellar nuclei from the Purkinje cells in the cortex, despite interruption of the major excitatory input to the Purkinje cells. 相似文献
35.
36.
37.
T. R. Brooks 《Journal of the National Medical Association》1996,88(5):300-304
This study was undertaken to determine the association between health providers'' stress and performances, and patients who presented with disability forms that the providers did not feel were justified. Two questionnaires were given to health-care providers at the Family Practice Clinic, Martin Luther King/Drew Medical Center, Los Angeles, California. One questionnaire assessed the level of stress they suffered from, and a second questionnaire assessed how these types of patients may affect their general performance. The data suggested that the performance of providers was definitely affected by hostile, demanding, threatening, and malingering patients. The students, residents, nurses, and clinic administrative staff were all affected. Third-year medical students and foreign-trained doctors appeared not to be affected as much, probably because of a lack of knowledge about the "system" or because they preferred not to "rock the boat". 相似文献
38.
Murine neurotropic retrovirus spongiform polioencephalomyelopathy: acceleration of disease by virus inoculum concentration. 总被引:4,自引:1,他引:4 下载免费PDF全文
A 10-fold reduction in the incubation period of murine neurotropic retrovirus spongiform polioencephalomyelopathy was effected by a 1,000-fold concentration of the cloned virus inoculum. 相似文献
39.
Atm is a stress-induced DNA damage checkpoint protein kinase with multiple roles in cell-cycle progression. Recent evidence indicates that Atm also plays a role in stem cell maintenance and self-renewal. It is not known whether Atm has a role during tissue regeneration. Using liver regeneration as a model system, we examined the role of Atm in this process. Here, we show that the expression levels of Atm protein were gradually increased during liver regeneration and this was correlated with the onset of DNA replication. The induction of Stat3 and JNK signaling, which are essential processes in normal regeneration response, was attenuated during the early phases of liver regeneration in Atm-deficient mice. P53 was transiently phosphorylated at serine 23 during liver regeneration in an Atm-dependent manner. In addition, we found that cyclin A induction was delayed and p21 was over-expressed, both of these processes were correlated with reduced and delayed DNA replication in Atm(-/-) mice during liver regeneration. Finally, we show that increased apoptosis was observed in Atm(-/-) mice in response to partial hepatectomy, indicating that Atm is required for the survival of hepatocytes. Collectively, these data indicate that liver regeneration is impaired in Atm-deficient mice. Given that liver is the first line of defense against environmental toxins, the elucidation of the function of Atm and Atm-mediated signaling pathways in liver metabolism and in response to environmental toxins is of fundamental interest. 相似文献
40.
Longitudinal study of viruses associated with canine infectious respiratory disease 总被引:6,自引:1,他引:6 下载免费PDF全文
In this investigation a population of dogs at a rehoming center was monitored over a period of 2 years. Despite regular vaccination of incoming dogs against distemper, canine adenovirus type 2 (CAV-2), and canine parainfluenza virus (CPIV), respiratory disease was endemic. Tissue samples from the respiratory tract as well as paired serum samples were collected for analysis. The development of PCR assays for the detection of CPIV, canine adenovirus types 1 and 2, and canine herpesvirus (CHV) is described. Surprisingly, canine adenovirus was not detected in samples from this population, whereas 19.4% of tracheal and 10.4% of lung samples were positive for CPIV and 12.8% of tracheal and 9.6% of lung samples were positive for CHV. As reported previously, a novel canine respiratory coronavirus (CRCoV) was detected in this population (K. Erles, C. Toomey, H. W. Brooks, and J. Brownlie, Virology 310:216-223, 2003). Infections with CRCoV occurred mostly during the first week of a dog's stay at the kennel, whereas CPIV and CHV were detected at later time points. Furthermore, the evaluation of an enzyme-linked immunosorbent assay for detection of antibodies to CPIV and an immunofluorescence assay for detection of antibodies to CHV is described. This study shows that CPIV is present at kennels despite vaccination. In addition, other agents such as CHV and CRCoV may play a role in the pathogenesis of canine respiratory disease, whereas CAV-2 and canine distemper virus were not present in this population, indicating that their prevalence in the United Kingdom is low due to widespread vaccination of dogs. 相似文献