全文获取类型
收费全文 | 509篇 |
免费 | 49篇 |
专业分类
耳鼻咽喉 | 8篇 |
儿科学 | 14篇 |
妇产科学 | 19篇 |
基础医学 | 95篇 |
口腔科学 | 16篇 |
临床医学 | 65篇 |
内科学 | 93篇 |
皮肤病学 | 14篇 |
神经病学 | 39篇 |
特种医学 | 26篇 |
外科学 | 51篇 |
综合类 | 2篇 |
预防医学 | 43篇 |
眼科学 | 3篇 |
药学 | 46篇 |
中国医学 | 4篇 |
肿瘤学 | 20篇 |
出版年
2023年 | 3篇 |
2022年 | 4篇 |
2021年 | 8篇 |
2020年 | 14篇 |
2019年 | 26篇 |
2018年 | 40篇 |
2017年 | 29篇 |
2016年 | 30篇 |
2015年 | 21篇 |
2014年 | 46篇 |
2013年 | 69篇 |
2012年 | 33篇 |
2011年 | 26篇 |
2010年 | 34篇 |
2009年 | 18篇 |
2008年 | 14篇 |
2007年 | 6篇 |
2006年 | 14篇 |
2005年 | 7篇 |
2003年 | 3篇 |
2001年 | 2篇 |
2000年 | 8篇 |
1999年 | 2篇 |
1998年 | 10篇 |
1997年 | 4篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1992年 | 5篇 |
1991年 | 4篇 |
1990年 | 2篇 |
1988年 | 2篇 |
1986年 | 2篇 |
1985年 | 8篇 |
1984年 | 3篇 |
1982年 | 2篇 |
1981年 | 4篇 |
1980年 | 3篇 |
1975年 | 4篇 |
1972年 | 3篇 |
1971年 | 2篇 |
1969年 | 3篇 |
1934年 | 2篇 |
1929年 | 1篇 |
1928年 | 1篇 |
1926年 | 2篇 |
1925年 | 1篇 |
1924年 | 3篇 |
1904年 | 1篇 |
排序方式: 共有558条查询结果,搜索用时 15 毫秒
101.
Predrag Ujić Igor Čeliković Aleksandar Kandić Ivana Vukanac Mirjana Đurašević Dušan Dragosavac Zora S. Žunić 《Applied radiation and isotopes》2010,68(1):201-206
The main scope of this paper is to point out the importance of introducing radon and thoron exhalation measurements from building materials in the regulating frame. Currently (2009), such a regulation of this kind of exposure is not explicitly included in the Serbian regulating network. To this end, this work reports concentration measurements of 226Ra, 232Th and 40K and radon and thoron exhalation rates from building materials used in Serbia. Following detailed analysis, it was noticed that both internal exposures to radon and/or thoron exhaling from building materials may exceed external exposures to their precursors contained therein. 相似文献
102.
103.
104.
Željka Babić Blanka Tariba Jelena Kovačić Alica Pizent Veda M. Varnai Jelena Macan 《Contraception》2013,87(6):790-800
Background and Study DesignIt is well documented that copper (Cu) blood levels are elevated in combination oral contraceptive (COC) users. The aim of this study was to establish the range of Cu increase in OC users compared to nonusers through a systematic literature overview and quantitative data analysis.ResultsTwenty-six articles were included in the meta-analysis. The increase in Cu level exponentially decreased in COC users over time, with a rapid decline through the 1960s and 1970s. After controlling for the publication year, use of COC increases the mean serum/plasma Cu level by 0.57 mg/L (95% confidence interval 0.49–0.66 mg/L).ConclusionCOCs commonly raise serum Cu to levels between 1.5 and 2 mg/L, which are above reference levels. Although these levels are not considered toxic, there are suggestions that such Cu increase could be implicated in oxidative pathophysiological processes in the body. Further research on safety of COCs use, including oxidative-stress-related effects, is warranted. 相似文献
105.
Zdeňka Žáková Manfred Pum Pavel Sedláček Hana Mlejnková František Hindák 《Oceanological and hydrobiological studies.》2013,42(4):412-419
The representatives of the genus Compsopogon Montagne in Bory et Durieaux (Rhodophyta) are basically tropical or subtropical algae. In central Europe they are only found in aquaria and in water bodies affected by thermal effluents, like the species C. aeruginosus (J. Agardh) Kützing in the Pulkau River (Austria), a tributary of the Dyje /Thaya River (Austria, Czech Republic). The first observation of this species was made in 2007 in the Pulkau River. In autumn 2010 the species was also observed at lower densities in an approximately 20 km section of the Dyje/Thaya River between the mouth of the Pulkau River (A) and the Nové Mlýny Reservoir (CR). Recently, the species was found also in Skryjský Brook, a tributary of the Jihlava River, below the cooling water effluent from the Dukovany Nuclear Power Plant, South Moravia, Czech Republic. This is the second finding of representatives of the genus Compsopogon in rivers in central Europe. 相似文献
106.
Fedor Valić PhD Eugenija Žusbrevekin MD 《Archives of environmental & occupational health》2013,68(5):359-364
Symptoms of byssinosis were found in 39% of 102 female hemp workers who were nonsmokers. A higher prevalence of chronic bronchitis (P < 0.01) was found in workers with symptoms of byssinosis than in those without such symptoms. In hemp workers, either with or without symptoms of byssinosis, FEV1.0 and FVC significantly decreased during work on the study days, Mondays and Thursdays; significantly lower reductions were registered on Thursdays. Inhalation of metaproterenol sulfate (Alupent) before work significantly diminished FEV1.0 reduction, although not completely preventing it. Metaproterenol inhalation after work significantly increased FEV1.0, indicating the reversibility of acute lung function changes during work. Comparison of lung function values measured before work with values obtained in the control group indicates a chronic effect of hemp dust on ventilatory function. 相似文献
107.
108.
Objectives
The incidence of cervical spine injuries in suicidal hangings with a short-drop has been reported to be extremely low or non-existent. The aim of this study was to determine the frequency and pattern of cervical spine injuries in suicidal hanging.Methods
A retrospective autopsy study was performed and short-drop suicidal hanging cases with documented cervical spine injuries were identified. This group was further analyzed with regard to the gender and age of the deceased, the position of the ligature knot, the presence of hyoid–laryngeal fractures, and the level of cervical spine injury.Results
Cervical spine injuries were present in 25 of the 766 cases, with an average age of 71.9 ± 10.7 years (range 39–88 years). In 16 of these 25 cases, the ligature knot was in the anterior position. The most common pattern of cervical spine injury included partial or complete disruption of the anterior longitudinal ligament and widening of the lower cervical spine disk spaces, associated with absence of hyoid–laryngeal fractures.Conclusions
Cervical spine injuries are not commonly found in short-drop suicidal hanging, occurring in only 3.3 % of all observed cases. Cervical spine injury may be occurring in 80 % of subjects aged 66.5 years and above. The most common pattern of cervical spine injury included anterior longitudinal ligament disruption of the lower cervical spine, disk space widening, and no vertebral body displacement. These injuries were mainly associated with an anterior knot position, and may be a consequence of loop pressure to the posterior neck and cervical spine hyperextension. 相似文献109.
110.
Irena Hočevar-Boltežar Mojca Matičič Maja Šereg-Bahar Nina Gale Mario Poljak Boštjan Kocjan Miha Žargi 《European archives of oto-rhino-laryngology》2014,271(12):3255-3262
In the case of an aggressive course of recurrent respiratory papillomatosis (RRP), adjuvant therapy can be used besides surgery. The aim of the study was to investigate the influence of vaccination with a quadrivalent vaccine against human papilloma viruses (HPV) types 6, 11, 16 and 18 on the course of RRP. Eleven subjects aged 13–46 years with a rapid growth of laryngeal papillomas were included in the study. They were vaccinated with three doses of the quadrivalent prophylactic HPV vaccine (Silgard®, MSD) and followed up for 12–52 months. The intervals between the successive surgical procedures, the extension of the disease (Derkay score) at each surgery, and the number of surgical procedures per year before vaccination and after its completion were compared. The mean interval between the surgical procedures was 271.2 days before the vaccination and 537.4 days after it (p = 0.034). The mean number of surgeries per year was 2.16 before the vaccination and 0.93 after it (p = 0.022). The Derkay score did not change significantly after vaccination. Complete remission of the disease was observed in one patient, partial response to the vaccination was observed in seven patients and no response was observed in three patients. In conclusion, vaccination with the quadrivalent HPV vaccine can favorably influence the course of RRP in patients with the rapid growth of the papillomas. It significantly prolongs the intervals between the surgical procedures and reduces the number of procedures needed in the majority of patients. The present investigation can serve as a pilot study for further research. For a final conclusion a longer follow-up and studies on more patients are necessary. 相似文献