全文获取类型
收费全文 | 1756篇 |
免费 | 95篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 15篇 |
妇产科学 | 16篇 |
基础医学 | 403篇 |
口腔科学 | 7篇 |
临床医学 | 90篇 |
内科学 | 295篇 |
皮肤病学 | 4篇 |
神经病学 | 221篇 |
特种医学 | 32篇 |
外科学 | 47篇 |
综合类 | 3篇 |
预防医学 | 374篇 |
眼科学 | 12篇 |
药学 | 305篇 |
中国医学 | 5篇 |
肿瘤学 | 22篇 |
出版年
2023年 | 16篇 |
2022年 | 35篇 |
2021年 | 47篇 |
2020年 | 43篇 |
2019年 | 38篇 |
2018年 | 32篇 |
2017年 | 36篇 |
2016年 | 36篇 |
2015年 | 62篇 |
2014年 | 113篇 |
2013年 | 107篇 |
2012年 | 82篇 |
2011年 | 122篇 |
2010年 | 91篇 |
2009年 | 89篇 |
2008年 | 89篇 |
2007年 | 99篇 |
2006年 | 90篇 |
2005年 | 95篇 |
2004年 | 81篇 |
2003年 | 78篇 |
2002年 | 59篇 |
2001年 | 52篇 |
2000年 | 36篇 |
1999年 | 29篇 |
1998年 | 17篇 |
1997年 | 18篇 |
1996年 | 21篇 |
1995年 | 8篇 |
1994年 | 5篇 |
1993年 | 5篇 |
1992年 | 4篇 |
1991年 | 8篇 |
1990年 | 4篇 |
1989年 | 7篇 |
1988年 | 7篇 |
1987年 | 6篇 |
1986年 | 7篇 |
1985年 | 10篇 |
1984年 | 12篇 |
1983年 | 12篇 |
1982年 | 5篇 |
1981年 | 6篇 |
1980年 | 9篇 |
1979年 | 7篇 |
1978年 | 3篇 |
1977年 | 9篇 |
1976年 | 5篇 |
1975年 | 2篇 |
排序方式: 共有1854条查询结果,搜索用时 17 毫秒
1.
2.
3.
《Ticks and Tick》2020,11(6):101540
Powassan virus (POWV) is a tickborne flavivirus discovered in Ontario, Canada in 1958 that causes long-term neurological sequelae in about half the reported cases and death in a little more than 10 % of cases. The incidence of POWV disease is rising in the United States but there is limited understanding of the scope and causes of recent changes in POWV epidemiology. We focus on quantifying the increase in human POWV disease incidence and infection prevalence in the United States. We also examine differences in the frequency of symptomatic cases and asymptomatic or mildly symptomatic cases, as well as limitations in national and state surveillance for POWV infection. We searched SCOPUS for all articles containing original POWV prevalence research, case studies, or literature reviews published in English. Case studies were supplemented by Morbidity and Mortality Weekly Report POWV data from the Centers for Disease Control and Prevention (CDC) and surveillance information from state health department websites. An increase in the number of POWV cases has been reported in the United States over the past 50 yr, and the geographic range of human POWV cases has expanded. The age distribution of symptomatic POWV cases has shifted, with significantly more individuals over 40 yr old being diagnosed after 1998. The emergence of POWV is due in large part to: (i) a change in transmission of POWV from a vector that rarely bites people (Ixodes cookei) to a new vector that often bites people (Ixodes scapularis) and has expanded its geographic range, (ii) enhanced surveillance efforts for arboviruses, and (iii) a greater awareness of POWV infection. 相似文献
4.
5.
《Vaccine》2019,37(48):7178-7182
The Ebola virus epidemic in West Africa proved to be the largest in the history of filovirus outbreaks, causing the World Health Organization to declare a public health emergency of international concern in August of 2014. In collaboration with domestic and international partners, the Biomedical Advanced Research and Development Authority (BARDA) initiated several vaccine development projects in support of the overall response efforts. The urgency associated with the epidemic triggered the clinical evaluation of lead vaccine candidates starting in late 2014. Here we will discuss development of the lead vaccine candidates for Ebola virus, specifically Zaire ebolavirus. 相似文献
6.
《Vaccine》2019,37(31):4310-4317
ONRAB® is a human adenovirus rabies glycoprotein recombinant vaccine developed to control rabies in wildlife. To support licensing and widespread use of the vaccine, safety studies are needed to assess its potential residual impact on wildlife populations. We examined the persistence of the ONRAB® vaccine virus in captive rabies vector and non-target mammals. This research complements work on important rabies vector species (raccoon, striped skunk, and red fox) but also adds to previous findings with the addition of some non-target species (Virginia opossum, Norway rats, and cotton rats) and a prolonged period of post vaccination monitoring (41 days). Animals were directly inoculated orally with the vaccine and vaccine shedding was monitored using quantitative real-time PCR applied to oral and rectal swabs. ONRAB® DNA was detected in both oral and rectal swabs from 6 h to 3 days post-inoculation in most animals, followed by a resurgence of shedding between days 17 and 34 in some species. Overall, the duration over which ONRAB® DNA was detectable was shorter for non-target mammals, and by day 41, no animal had detectable DNA in either oral or rectal swabs. All target species, as well as cotton rats and laboratory-bred Norway rats, developed robust humoral immune responses as measured by competitive ELISA, with all individuals being seropositive at day 31. Similarly, opossums showed good response (89% seropositive; 8/9), whereas only one of nine wild caught Norway rats was seropositive at day 31. These results support findings of other safety studies suggesting that ONRAB® does not persist in vector and non-target mammals exposed to the vaccine. As such, we interpret these data to reflect a low risk of adverse effects to wild populations following distribution of ONRAB® to control sylvatic rabies. 相似文献
7.
8.
Janna Lesser Deborah Koniak-Griffin Evelyn Gonzalez-Figueroa Rong Huang William G Cumberland 《The Journal of the Association of Nurses in AIDS Care》2007,18(2):18-27
Pregnant and parenting adolescents living in inner cities are at risk for acquiring HIV through unprotected sexual activity. In addition to individual risk behaviors, a lack of socioeconomic and other environmental resources create risk environments that make certain communities vulnerable to both adolescent pregnancy and HIV/AIDS. Research indicates that adolescent parents, many who have histories of childhood trauma, may use their experience of young parenthood and the concomitant feelings of parental protectiveness as a source of renewed hope for their future. The purpose of this report is to explore the relationship between history of childhood abuse and high risk behaviors in adolescent Latino mothers and fathers enrolled in a randomized clinical trial of a culturally rooted, couple-focused HIV prevention program. In addition, this report describes the HIV prevention program that was designed specifically for young Latino parents wherein maternal and paternal protectiveness are viewed as intrinsic and developing critical factors that promote resiliency and motivate behavioral change. 相似文献
9.
10.
A randomized, double-blind, placebo-controlled clinical trial was conducted to determine the effects of a low-dose (<2 times the Recommended Dietary Allowance) micronutrient supplement containing trace minerals (zinc and selenium) and/or vitamins/provitamins (vitamin C, α-tocopherol, and β-carotene) on the incidence of respiratory and urogenital infections in institutionalized elderly. After 2 years, there was a significant decrease in the mean number of infections in elders given trace elements (p < 0.01) but not vitamins. 相似文献