全文获取类型
收费全文 | 4944篇 |
免费 | 407篇 |
国内免费 | 14篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 140篇 |
妇产科学 | 78篇 |
基础医学 | 609篇 |
口腔科学 | 208篇 |
临床医学 | 563篇 |
内科学 | 1035篇 |
皮肤病学 | 43篇 |
神经病学 | 513篇 |
特种医学 | 199篇 |
外科学 | 416篇 |
综合类 | 141篇 |
一般理论 | 3篇 |
预防医学 | 606篇 |
眼科学 | 58篇 |
药学 | 439篇 |
中国医学 | 1篇 |
肿瘤学 | 299篇 |
出版年
2022年 | 41篇 |
2021年 | 71篇 |
2020年 | 45篇 |
2019年 | 72篇 |
2018年 | 81篇 |
2017年 | 56篇 |
2016年 | 72篇 |
2015年 | 69篇 |
2014年 | 103篇 |
2013年 | 157篇 |
2012年 | 251篇 |
2011年 | 230篇 |
2010年 | 144篇 |
2009年 | 161篇 |
2008年 | 227篇 |
2007年 | 214篇 |
2006年 | 173篇 |
2005年 | 196篇 |
2004年 | 171篇 |
2003年 | 167篇 |
2002年 | 201篇 |
2001年 | 146篇 |
2000年 | 164篇 |
1999年 | 131篇 |
1998年 | 78篇 |
1997年 | 69篇 |
1996年 | 71篇 |
1995年 | 62篇 |
1994年 | 47篇 |
1993年 | 53篇 |
1992年 | 113篇 |
1991年 | 94篇 |
1990年 | 114篇 |
1989年 | 91篇 |
1988年 | 100篇 |
1987年 | 92篇 |
1986年 | 100篇 |
1985年 | 80篇 |
1984年 | 61篇 |
1983年 | 55篇 |
1982年 | 46篇 |
1981年 | 39篇 |
1980年 | 34篇 |
1979年 | 55篇 |
1978年 | 47篇 |
1977年 | 37篇 |
1974年 | 41篇 |
1973年 | 35篇 |
1970年 | 42篇 |
1968年 | 41篇 |
排序方式: 共有5365条查询结果,搜索用时 15 毫秒
991.
Yuming Guo Shilu Tong Shanshan Li Adrian G Barnett Weiwei Yu Yanshen Zhang Xiaochuan Pan 《Environmental health : a global access science source》2010,9(1):57
Background
A number of epidemiological studies have been conducted to research the adverse effects of air pollution on mortality and morbidity. Hypertension is the most important risk factor for cardiovascular mortality. However, few previous studies have examined the relationship between gaseous air pollution and morbidity for hypertension. 相似文献992.
Darren ER Warburton Sarah Charlesworth Adam Ivey Lindsay Nettlefold Shannon SD Bredin 《The international journal of behavioral nutrition and physical activity》2010,7(1):1-220
This systematic review examines critically the scientific basis for Canada's Physical Activity Guide for Healthy Active Living for adults. Particular reference is given to the dose-response relationship between physical activity and premature all-cause mortality and seven chronic diseases (cardiovascular disease, stroke, hypertension, colon cancer, breast cancer, type 2 diabetes (diabetes mellitus) and osteoporosis). The strength of the relationship between physical activity and specific health outcomes is evaluated critically. Literature was obtained through searching electronic databases (e.g., MEDLINE, EMBASE), cross-referencing, and through the authors' knowledge of the area. For inclusion in our systematic review articles must have at least 3 levels of physical activity and the concomitant risk for each chronic disease. The quality of included studies was appraised using a modified Downs and Black tool. Through this search we identified a total of 254 articles that met the eligibility criteria related to premature all-cause mortality (N = 70), cardiovascular disease (N = 49), stroke (N = 25), hypertension (N = 12), colon cancer (N = 33), breast cancer (N = 43), type 2 diabetes (N = 20), and osteoporosis (N = 2). Overall, the current literature supports clearly the dose-response relationship between physical activity and the seven chronic conditions identified. Moreover, higher levels of physical activity reduce the risk for premature all-cause mortality. The current Canadian guidelines appear to be appropriate to reduce the risk for the seven chronic conditions identified above and all-cause mortality. 相似文献
993.
Reporting of diabetes on death certificates of 1872 people with type 2 diabetes in Tayside, Scotland
BACKGROUND: It has been suggested that diabetes is under-recorded on death certificates. METHODS: We examined the death certificates of 1,872 people with type 2 diabetes in Tayside, Scotland, to determine how frequently diabetes was recorded. RESULTS: Diabetes was mentioned on the certificates of 42.8% and was the underlying cause of death for 6.4%. There was mention of diabetes for 51.3% of the 811 people for whom cardiovascular disease was the underlying cause of death. Being male was associated with less frequent mention of diabetes, with more frequent mention associated with increasing duration of diabetes, increasing age and underlying cardiovascular cause of death. CONCLUSIONS: This study highlights the limitations of using routine mortality data for monitoring the burden of diabetes in populations. 相似文献
994.
In this study, immunizations at 2 weeks vs. 6 weeks intervals, with an HIV-1 envelope protein in adjuvants, through intra-nasal (IN), intra-muscular (IM), IN followed by IM (IN/IM) and IM/IN, were compared for induction of mucosal and systemic immune responses. IN/IM immunizations at 2, but not at 6, week intervals induced the highest mucosal and systemic immune responses compared to other immunization routes. Following a resting memory phase, IN boosting of IN/IM-immunized mice, compared to IM-boosting of IM-immunized mice, induced increased IgA responses. Thus, depending on the immunization intervals, IN/IM may be more effective than IM immunizations for short- and long-term immunity. 相似文献
995.
Adverse event reports following yellow fever vaccination 总被引:1,自引:0,他引:1
Lindsey NP Schroeder BA Miller ER Braun MM Hinckley AF Marano N Slade BA Barnett ED Brunette GW Horan K Staples JE Kozarsky PE Hayes EB 《Vaccine》2008,26(48):6077-6082
Yellow fever (YF) vaccine has been used for prevention of YF since 1937 with over 500 million doses administered. However, rare reports of severe adverse events following vaccination have raised concerns about the vaccine's safety. We reviewed reports of adverse events following YF vaccination reported to the U.S. Vaccine Adverse Event Reporting System (VAERS) from 2000 to 2006. We used estimates of age and sex distribution of administered doses obtained from a 2006 survey of authorized vaccine providers to calculate age- and sex-specific reporting rates of all serious adverse events (SAE), anaphylaxis, YF vaccine-associated neurotropic disease, and YF vaccine-associated viscerotropic disease. Reporting rates of SAEs were substantially higher in males and in persons aged > or =60 years. These findings reinforce the generally acceptable safety profile of YF vaccine, but highlight the importance of physician and traveler education regarding the risks and benefits of YF vaccination, particularly for travelers > or =60 years of age. Vaccination should be limited to persons traveling to areas where the risk of YF is expected to exceed the risk of serious adverse events after vaccination, or if not medically contraindicated, where national regulations require proof of vaccination to prevent introduction of YF. 相似文献
996.
Caputo A Brocca-Cofano E Castaldello A Voltan R Gavioli R Srivastava IK Barnett SW Cafaro A Ensoli B 《Vaccine》2008,26(9):1214-1227
The development of a vaccine against HIV/AIDS capable of inducing broad humoral and cellular responses at both systemic and mucosal sites, able to stop or reduce viral infection at the portal of entry, represents the only realistic way to control the infection caused by HIV world-wide. The promising results obtained with the HIV-1 Tat-based vaccines in preclinical and clinical settings, the evidence that a broad immunity against HIV correlates with reduced viral load or virus control, as well as the availability of novel gp140 V2-loop deleted HIV-1 Env (DeltaV2Env) immunogens capable of inducing cross-reactive neutralizing antibodies, have led to the design of new vaccine strategies based on the combination of non-structural and structural proteins. In this study, we demonstrate that immunization with a biologically active HIV-1 Tat protein in combination with the oligomeric HIV-1 gp140 DeltaV2Env and/or SIV Gag proteins, delivered intranasally with the detoxified LTK63 mucosal adjuvant, whose safety has been recently shown in humans, elicits long-lasting local and systemic antibody and cellular immune responses against the co-administered antigens in a fashion similar to immune responses induced by vaccination with Tat, DeltaV2Env and Gag proteins alone. The results indicate lack of antigen interference implying that HIV-1 Tat is an optimal co-antigen for combined vaccine strategies employing DeltaV2Env and/or Gag proteins. 相似文献
997.
998.
OBJECTIVE: To evaluate the relative skeletal and dental changes produced by the crown- or banded-type Herbst appliance in growing Class II division 1 malocclusion cases. MATERIALS AND METHODS: Several electronic databases were searched with the help of a health sciences librarian, without language limitation. Abstracts that appeared to fulfill the initial selection criteria (Herbst use and clinical trial) were selected by consensus, and their original articles were then retrieved. Clinical trials were selected that used lateral cephalograms to assess immediate skeletal and dental changes from the use of either crown or banded Herbst appliances. Clinical trials that employed other simultaneous potentially growth-modifying appliances or surgery were excluded. A comparable untreated Class II division 1 malocclusion control group was required to factor out normal growth changes. References from the selected articles were also hand searched. RESULTS: Only three articles meet the selection criteria. Proclination and anterior movement of the lower incisors, overjet reduction, and improvement of first molar relationship thorough mesial movement of the first molars, reduction of ANB angle, and an increase in the mandibular plane angle were reported. There were mixed findings as to mandibular sagittal length and position and increases in lower face height, both anteriorly and posteriorly. No statistically significant changes were noted in the sagittal length or position of the skeletal maxilla. CONCLUSIONS: Dental changes have more impact than skeletal changes in the correction of Class II division 1 malocclusions with the crown or banded Herbst appliance. 相似文献
999.
Future challenges and therapeutic opportunities in type 2 diabetes: Changing the paradigm of current therapy 下载免费PDF全文
David R. Owens CBE MD FRCP Louis Monnier MD Anthony H. Barnett MD FRCP 《Diabetes, obesity & metabolism》2017,19(10):1339-1352
Most algorithms for type 2 diabetes mellitus (T2DM) do not recommend treatment escalation until glycated haemoglobin (HbA1c) fails to reach the recommended target of 7% (53 mmol/mol) within approximately 3 months on any treatment regimen (“treat to failure”). Clinical inertia and/or poor adherence to therapy contribute to patients not reaching glycaemic targets when managed according to this paradigm. Clinical inertia exists across the entire spectrum of anti‐diabetes therapies, although it is most pronounced when initiating and optimizing insulin therapy. Possible reasons include needle aversion, fear of hypoglycaemia, excessive weight gain and/or the need for increased self‐monitoring of blood glucose. Studies have suggested, however, that early intensive insulin therapy in newly diagnosed, symptomatic patients with T2DM with HbA1c >9% (75 mmol/mol) can preserve beta‐cell function, thereby modulating the disease process. Furthermore, postprandial plasma glucose is a key component of residual dysglycaemia, evident especially when HbA1c remains above target despite fasting normoglycaemia. Therefore, to achieve near normoglycaemia, additional treatment with prandial insulin or a glucagon‐like peptide‐1 receptor agonist (GLP‐1 RA) is often required. Long‐ or short‐acting GLP‐1 RAs offer effective alternatives to basal or prandial insulin in patients inadequately controlled with other therapies or basal insulin alone, respectively. This review highlights the limitations of current algorithms, and proposes an alternative based on the early introduction of insulin therapy and the rationale for the sequential or fixed combination of GLP‐1 RAs with insulin (“treat‐to‐success” paradigm). 相似文献
1000.