全文获取类型
收费全文 | 1871篇 |
免费 | 116篇 |
国内免费 | 22篇 |
专业分类
耳鼻咽喉 | 43篇 |
儿科学 | 56篇 |
妇产科学 | 20篇 |
基础医学 | 230篇 |
口腔科学 | 52篇 |
临床医学 | 192篇 |
内科学 | 429篇 |
皮肤病学 | 15篇 |
神经病学 | 260篇 |
特种医学 | 133篇 |
外科学 | 183篇 |
综合类 | 4篇 |
预防医学 | 74篇 |
眼科学 | 53篇 |
药学 | 119篇 |
中国医学 | 4篇 |
肿瘤学 | 142篇 |
出版年
2023年 | 8篇 |
2022年 | 17篇 |
2021年 | 38篇 |
2020年 | 25篇 |
2019年 | 23篇 |
2018年 | 32篇 |
2017年 | 33篇 |
2016年 | 45篇 |
2015年 | 52篇 |
2014年 | 66篇 |
2013年 | 83篇 |
2012年 | 99篇 |
2011年 | 105篇 |
2010年 | 75篇 |
2009年 | 65篇 |
2008年 | 94篇 |
2007年 | 118篇 |
2006年 | 90篇 |
2005年 | 99篇 |
2004年 | 113篇 |
2003年 | 122篇 |
2002年 | 110篇 |
2001年 | 36篇 |
2000年 | 40篇 |
1999年 | 39篇 |
1998年 | 23篇 |
1997年 | 22篇 |
1996年 | 22篇 |
1995年 | 16篇 |
1994年 | 21篇 |
1993年 | 15篇 |
1992年 | 17篇 |
1991年 | 15篇 |
1990年 | 32篇 |
1989年 | 15篇 |
1988年 | 27篇 |
1987年 | 7篇 |
1986年 | 11篇 |
1985年 | 11篇 |
1984年 | 13篇 |
1983年 | 7篇 |
1982年 | 9篇 |
1981年 | 8篇 |
1979年 | 10篇 |
1974年 | 7篇 |
1972年 | 11篇 |
1971年 | 11篇 |
1969年 | 7篇 |
1967年 | 6篇 |
1966年 | 8篇 |
排序方式: 共有2009条查询结果,搜索用时 312 毫秒
61.
62.
Yamaguchi M Azuma H Fujihara M Hamada H Ikeda H 《Scandinavian journal of immunology》2007,65(6):581-588
The number of mast cells (MC) that can be obtained from tissue is limited, making it difficult to study the role of MC. Cultured MC derived from cord blood (CB)-CD34(+) cells proliferate well compared with those derived from adult CD34(+) cells; however, they have been reported to be phenotypically or functionally immature regardless of culture system. For example, very few cells express FcepsilonRI. To resolve this problem, we addressed the effect of human bone marrow stromal cell line on the development of cultured MC. CB-CD34(+) (1 x 10(4)) cells were cultured for 8 weeks in a serum-free medium containing rhIL-6 and rhSCF with or without a human bone marrow stromal cell line, namely, co-culture and liquid culture, and were compared in various regards. MC were basically determined by metachromatic staining of granules. The number of MC obtained (60.3 +/- 15.8 x 10(5) versus 2.0 +/- 1.0 x 10(5)), percentage of FcepsilonRI(+) cells (29.3 +/- 9.4% versus 1.9 +/- 0.8%), histamine content (9.7 +/- 2.8 pg/cell versus 5.8 +/- 2.3 pg/cell), and IgE-mediated histamine release (46 +/- 10% versus 17 +/- 7%) were higher (P < 0.01 and P < 0.05) in the co-culture than in the liquid culture. When CB-CD34(+) cells were developed in liquid culture with the co-culture supernatant (CM), a significant increase (P < 0.01) in the percentage of FcepsilonRI(+) cells and in cell number was observed but these values were lower than those of co-cultured MC. We concluded that this co-culture system was useful for obtaining a considerable number of mature MC with a high basal level of functional FcepsilonRI expression from CB-CD34(+) cells. Yet unknown humoral factors in CM may partly mediate this effect. 相似文献
63.
64.
65.
Masumoto Yoshinobu Fukunishi Shigeo Fukui Tomokazu Yoshiya Shinichi Nishio Shoji Fujihara Yuki Okahisa Shohei Okada Taishi Kanto Makoto Goshi Ariha Morio Futoshi Takeda Yu 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2020,30(3):465-472
European Journal of Orthopaedic Surgery & Traumatology - Combined anteversion (CA) technique (stem-first procedure) is generally accepted as the optimal technique to attain an appropriate CA... 相似文献
66.
Mari Akiyama Katsuhiro Kobayashi Takushi Inoue Tomoyuki Akiyama Harumi Yoshinaga 《Brain & development》2014
Purpose: Ictal fear is an uncommon condition in which fear manifests as the main feature of epileptic seizures. The literature has suggested that ictal fear is generally associated with poor seizure outcomes. We wanted to clarify the variability in seizure outcome of children with ictal fear. Subjects and methods: We identified five pediatric patients with ictal fear who were followed up on at Okayama University Hospital between January 2003 and December 2012. We retrospectively reviewed their clinical records and EEG findings. Results: The onset age of epilepsy ranged from 8 months to 9 years and 10 months. The common ictal symptoms were sudden fright, clinging to someone nearby, and subsequent impairment of consciousness, which were often accompanied by complex visual hallucinations and psychosis-like complaints. Ictal fear, in four patients, was perceived as a nonepileptic disorder by their parents. Ictal electroencephalograms (EEG) of ictal fear were obtained in all patients. Three showed frontal onset, while the other two showed centrotemporal or occipital onsets. Two patients were seizure free at last follow-up, while seizures persisted in the other three. A patient with seizure onset during infancy had a favorable outcome, which was considered to be compatible with benign partial epilepsy with affective symptoms. Conclusion: Ictal fear is not always associated with a symptomatic cause or a poor seizure outcome. It is quite important to make a correct diagnosis of ictal fear as early as possible to optimize treatment. 相似文献
67.
Tomoyuki Akiyama Katsuhiro Kobayashi Akihito Higashikage Junko Sato Harumi Yoshinaga 《Brain & development》2014
Objective: We intended to investigate the effects of age, gender, and medications on amino acid cerebrospinal fluid (CSF)/plasma ratios in children, and to determine whether amino acid transports across the blood–CSF barrier in children differ from those in adults. Patients and methods: Amino acid concentrations measured by ion-exchange high-performance liquid chromatography were used (CSF from 99 children, simultaneously collected plasma from 76 children). Influence of age, gender, and medications on the amino acid CSF concentrations and CSF/plasma ratios were analyzed by linear multiple regression. Interactions of amino acid transports were analyzed by correlation analysis of CSF/plasma ratios. Results: CSF/plasma ratios of serine, valine, histidine, and arginine were higher in younger children. The glutamate CSF/plasma ratio was higher in older children. Serine, alanine, threonine, valine, and histidine CSF/plasma ratios were lower in females. Glutamine, methionine, tyrosine, and phenylalanine CSF/plasma ratios were elevated with valproate therapy. Serine, threonine, valine, leucine, and tyrosine CSF/plasma ratios were lower with clobazam therapy. The asparagine CSF/plasma ratio was elevated with pyridoxal phosphate therapy. Transports of most essential neutral amino acids interacted with each other, as did neutral amino acids with low molecular weights. Cationic amino acids interacted with each other and some essential neutral amino acids. Acidic amino acids had no interactions with other amino acids. Conclusions: Age, gender, and anti-epileptic drugs affect amino acid CSF/plasma ratios in children. Transport interactions between amino acids in children showed no remarkable difference from those of adults and generally followed the substrate specificities of multiple amino acid transport systems. 相似文献
68.
Jong-Hwan Park Masashi Miyashita Masaki Takahashi Noriaki Kawanishi Harumi Hayashida Hyun-Shik Kim Katsuhiko Suzuki Yoshio Nakamura 《Journal of Sports Science and Medicine》2014,13(3):624-631
Although numerous sources of evidence show that regular physical activity is beneficial to health, most individuals do not engage in a sufficient amount of physical activity to meet the guidelines set out by expert panels. In addition, the minimum amount of physical activity associated with reduced cardiovascular disease risk markers is not clear in older adults. The purpose of this study was to determine the effects of a 12-week walking program involving an exercise volume below the current minimum physical activity recommendation on cardiovascular disease risk markers in older adults. The participants were recruited from the following two groups separately: a walking group (n = 14) and a control group (n = 14). In the walking group, participants walked 30 to 60 minutes per session on 2 days per week for 12 weeks (average walking time, 49.4 ± 8.8 min/session). Plasma oxidised low-density lipoprotein concentrations tended to be lower than baseline values in the walking group after 12 weeks (paired t-test, p = 0.127). The ratio of oxidised low-density lipoprotein to high-density lipoprotein cholesterol was significantly lower than the baseline ratio in the walking group after 12 weeks (paired t-test, p = 0.035). Resting systolic blood pressure and diastolic blood pressure were significantly lower than baseline values in the walking group after 12 weeks (paired t-tests, p = 0.002, p < 0.0005, respectively). Our findings demonstrate that a 12-week walking program comprising a low volume of physical activity confers a benefit to cardiovascular-related health in older adults.
Key Points
- It is important to consider baseline physical activity levels when evaluating physical activity program.
- Being physically active is important to reduce the potential risk marker of cardiovascular disease in older adults.
- These data imply that a small volume of 12-week walking program confers a benefit to cardiovascular-related health in older adults.
69.
70.
Yasuhiro Matsubayashi MD Akihiro Yoshida PhD Hideki Suganami PhD Momoko Oe MS Takaaki Sato MD Yuta Yaguchi MD Kazuya Fujihara MD Takaho Yamada MD Shiro Tanaka PhD Kohei Kaku MD Hirohito Sone MD 《Diabetes, obesity & metabolism》2021,23(7):1660-1665
Sodium-glucose cotransporter-2 inhibitors (SGLT2) are drugs that have been reported to have several effects through the regulation of plasma volume, for example, antihypertensive effects. This study aimed to clarify the impact of long-term administration and subsequent discontinuation of the SGLT2 inhibitor tofogliflozin on estimated plasma volume (ePV), brain natriuretic peptide (BNP) and the relationship between changes in ePV, BNP and body weight (BW). Data from 157 participants with type 2 diabetes receiving tofogliflozin monotherapy in a phase 3 study were analysed. Changes in variables or correlations among them during a 52-week administration and a 2-week post-treatment period were investigated. Percent change in ePV was calculated using the Strauss formula. Significant decreases in BW, ePV and ln-transformed BNP (ln-BNP) were noted by week 52. %ΔBW was not significantly correlated with %ΔePV and Δln-BNP, while %ΔePV was significantly correlated with Δln-BNP. Two weeks after discontinuation of tofogliflozin, BW, ePV and ln-BNP were significantly increased. %ΔBW was significantly correlated with %ΔePV and Δln-BNP. Furthermore, ePV and BNP were significantly higher than baseline levels. 相似文献