全文获取类型
收费全文 | 31833篇 |
免费 | 1545篇 |
国内免费 | 159篇 |
专业分类
耳鼻咽喉 | 329篇 |
儿科学 | 788篇 |
妇产科学 | 394篇 |
基础医学 | 3994篇 |
口腔科学 | 831篇 |
临床医学 | 2094篇 |
内科学 | 8449篇 |
皮肤病学 | 508篇 |
神经病学 | 2210篇 |
特种医学 | 1124篇 |
外科学 | 6026篇 |
综合类 | 138篇 |
一般理论 | 3篇 |
预防医学 | 956篇 |
眼科学 | 373篇 |
药学 | 2187篇 |
中国医学 | 102篇 |
肿瘤学 | 3031篇 |
出版年
2023年 | 181篇 |
2022年 | 308篇 |
2021年 | 558篇 |
2020年 | 292篇 |
2019年 | 414篇 |
2018年 | 514篇 |
2017年 | 451篇 |
2016年 | 502篇 |
2015年 | 481篇 |
2014年 | 656篇 |
2013年 | 838篇 |
2012年 | 1315篇 |
2011年 | 1354篇 |
2010年 | 846篇 |
2009年 | 748篇 |
2008年 | 1333篇 |
2007年 | 1486篇 |
2006年 | 1477篇 |
2005年 | 1548篇 |
2004年 | 1501篇 |
2003年 | 1472篇 |
2002年 | 1397篇 |
2001年 | 1195篇 |
2000年 | 1282篇 |
1999年 | 1099篇 |
1998年 | 433篇 |
1997年 | 310篇 |
1996年 | 318篇 |
1995年 | 292篇 |
1994年 | 259篇 |
1993年 | 259篇 |
1992年 | 777篇 |
1991年 | 717篇 |
1990年 | 678篇 |
1989年 | 733篇 |
1988年 | 647篇 |
1987年 | 606篇 |
1986年 | 547篇 |
1985年 | 521篇 |
1984年 | 342篇 |
1983年 | 284篇 |
1979年 | 263篇 |
1978年 | 187篇 |
1977年 | 160篇 |
1974年 | 157篇 |
1973年 | 166篇 |
1972年 | 167篇 |
1971年 | 157篇 |
1970年 | 155篇 |
1969年 | 143篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Hori Hiroki Ohta Asuka Matsui Honami Yano Kanako Morita-Tominaka Miyuki Linn Zayar Masumoto Daisuke Okumura Yosuke Okamura Satoshi Kurihara Kosuke Hayakawa Akira Rikiishi Takeshi Kobayashi Kyoko 《International journal of clinical oncology / Japan Society of Clinical Oncology》2022,27(1):245-252
International Journal of Clinical Oncology - The practice of cancer diagnosis disclosure to children has been changed with the times. The regulations of clinical trials in the 2000s might change... 相似文献
2.
3.
4.
5.
Yoshifumi Kan 《中华心血管病杂志》2003,31(Z1):62
Many institutions in Japan perform PCI via the radial artery(TRI), due to the adility of TRI to improve the quality of life of patients. However, this procedure involves the significant problem of causing narrowing of the radial artery or occlusion by trans-radial approach. 相似文献
6.
Toshio Imaizumi MD PhD Toshimi Honma MD PhD Yoshifumi Horita MD Ikuhide Kohama MD PhD Kei Miyata MD Maiko Kawamura MD Jun Niwa MD PhD 《Journal of neuroimaging》2006,16(3):236-242
BACKGROUND AND PURPOSE: Dot-like low intensity spots (dot-like hemosiderin spots: dotHSs) on gradient echo T2*-weighted MRI have been histologically diagnosed to represent old cerebral microbleeds associated with microangiopathies. They have also been correlated to the fragility of small vessels and the tendency to bleed. Therefore, a substantial number of dotHSs might be associated with a large-sized, deep intracerebral hematoma (ICH). On the other hand, dotHSs may reflect old microbleeds that did not enlarge to symptomatic size. METHODS: To investigate how dotHSs are related to the size (maximal diameter) of primary deep ICH, we analyzed the diameter and the number of dotHSs in 151 patients with deep ICH not associated with subarachnoid hemorrhage or intraventricular hemorrhage (75 males and 76 females, age ranged from 37 to 90 [65.7 +/- 11.3 years old] who were consecutively admitted to Hakodate Municipal Hospital. The hazard ratio (HR) for a maximal diameter of deep ICH < or =2 cm was estimated, using the number of dotHSs and risk factors for stroke. RESULTS: The number of dotHSs associated with the diameter < or =2 cm was 9.2 +/- 11.5, significantly larger than that with the diameter > or =2 cm (4.7 +/- 7.0, P= .012). Multivariate analysis revealed that a maximal diameter of deep ICH of < or =2 cm was found in patients with dotHS (HR, 3.7; 95% confidence interval [CI], 1.4-10.1; P= .009). CONCLUSION: Though small sample size limited the power of our analyses, these findings suggest that the number of dotHSs may be associated with a small diameter of deep ICH. 相似文献
7.
Kenichi Okubo Masashi Kobayashi Hiromasa Morikawa Eiichi Hayatsu 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2006,54(7):268-272
Objective: Induction chemoradiotherapy followed by anatomical resection is a current therapeutic strategy for non-small-cell lung cancer
with mediastinal node involvement. Dense peritracheal fibrosis and sclerosis after chemoradiotherapy cause difficult mediastinal
node dissection. We evaluated a novel technique to make the mediastinal node dissection easier after induction therapy. Methods: At the end of mediastinoscopic node biopsy for staging of lung cancer, cotton-type collagen was inserted anterior and lateral
to the trachea in patients with pathologically confirmed mediastinal node involve-ment (n=45). The induction therapy consisted
of concurrent use of platinum-based chemotherapy and hyperfractionated radiotherapy. After the chemoradiotherapy all patients
underwent a pulmonary resection with complete mediastinal node dissection 7–12 weeks after the collagen insertion. Surgical
findings of the mediastinum and the time for node dissection were compared with those without collagen insertion at mediastinoscopy
after chemoradiotherapy (n=5). Results: All five patients without collagen insertion showed sclerotic and fibrotic change of mediastinal nodes with severe adhesion
to the trachea. In 42 of 45 patients with collagen insertion (93.3%) the collagen remained unabsorbed and separated the mediastinal
nodes from the trachea. Mediastinal node dissection was easily accomplished by removing mediastinal tissues lateral and anterior
to the collagen. The rate of mediastinal node separation was significantly higher with collagen insertion than without (p<
0.0001). The times for node dissection in patients with and without collagen insertion showed no significant difference. Conclusion: Cotton-type collagen insertion at staging mediastinoscopy for lung cancer separates the mediastinal nodes from the trachea
and makes the node dissection easier after induction chemoradiotherapy. 相似文献
8.
Concurrent presence of metabolic syndrome in obstructive sleep apnea syndrome exacerbates the cardiovascular risk: a sleep clinic cohort study. 总被引:2,自引:0,他引:2
Kazuki Shiina Hirofumi Tomiyama Yoshifumi Takata Yasuhiro Usui Kihiro Asano Yoji Hirayama Takeshi Nakamura Akira Yamashina 《Hypertension research》2006,29(6):433-441
This cross-sectional study was conducted to examine whether the obstructive sleep apnea syndrome (OSAS) is associated with elevation of the pulse wave velocity (PWV) and increase in the plasma levels of C-reactive protein (CRP), both of which are known markers of cardiovascular risk, and also to determine if the concurrent presence of the metabolic syndrome might exacerbate this elevation in the levels of these cardiovascular risk markers in subjects with OSAS. With these objectives, the PWV and serum CRP were measured in 184 subjects attending a sleep clinic. It was found that the PWV and CRP were higher in the subjects with OSAS (n=94) than in those without OSAS (n=90). Furthermore, among the subjects with OSAS, the PWV and CRP were higher in those with the concurrent presence of the metabolic syndrome (n= 41; PWV=1,562+/-19 cm/s; CRP=1.8+/-0.2 mg/l) than in those without metabolic syndrome (n=53; PWV=1,432+/-21 cm/s; CRP=1.2+/-0.1 mg/l) (p<0.05). A general linear model analysis demonstrated that OSAS and metabolic syndrome were independently associated with elevated PWV and increase of the plasma levels of CRP. OSAS appears to be associated with increased cardiovascular risk, as reflected by both elevated PWV and increase of the plasma CRP. The concurrent presence of metabolic syndrome may exacerbate this increase in cardiovascular risk in subjects with OSAS. Therefore, the concurrent presence of metabolic syndrome may constitute an additive cardiovascular risk factor in subjects with OSAS. 相似文献
9.
Katsuo Kamata Ayako Makino Noriyasu Kanie Shu-ichi Oda Takayuki Matsumoto Tsuneo Kobayashi Toyohiko Kikuchi Masato Nishimura Toshio Honda 《Journal of Smooth Muscle Research》2006,42(2-3):75-88
Anthocyanins, which are responsible for a variety of bright colors (including red, blue, and purple) in fruits, vegetables, and flowers, are consumed as dietary polyphenols. Anthocyanin-containing fruits are thought to decrease coronary heart disease and are used in anti-diabetic preparations. Diabetes is associated with a variety of cardiovascular complications that may be mediated by endothelial dysfunction, and so this study was designed mainly to characterize the influence of a synthesized anthocyanidin derivative (HK-008) over acetylcholine (ACh)-induced relaxation in mesenteric arterial beds isolated from rats. In a glucose-tolerance test in intact rats, HK-008 (30 mg/kg) reduced the glucose level as effectively as the same dose of glibenclamide. The aortic relaxation induced by pinacidil (an ATP-sensitive potassium channel opener) was greatly inhibited by glibenclamide (10 microM), and also significantly inhibited by HK-008 (10 microM). Interestingly, the ACh-induced relaxation in the perfused, preconstricted mesenteric arterial bed was significantly enhanced by HK-008 (10 microM), and this enhancement was significantly attenuated by indomethacin (10 microM). The ACh-induced mesenteric relaxation was impaired by an increase in oxidative stress, viz. superoxide-generating treatment [xanthine oxidase (XO; 0.1 U/ml) plus hypoxanthine (HX; 10 microM)]. However, this impairment was strongly suppressed by HK-008 (10 microM). These results suggest that HK-008 increases endothelium-induced relaxation by suppressing oxidative stress or modulating prostanoids signaling. This compound may therefore be useful against certain cardiovascular disorders. 相似文献
10.
Neurotransmitter- or neuromodulator-like actions ofl-DOPA were investigated with intracellular recordings from submucous plexus neurons of the guinea-pig caecum.l-DOPA at 30 nM augmented the amplitude of fast EPSPs, but did not affect depolarizations elicited by puff application of acetylcholine (ACh). The augmenting effect ofl-DOPA on the fast EPSPs was counteracted byl-DOPA methyl ester. The fast EPSPs were depressed by 10 μMl-DOPA, but transiently augmented after rinsing the drug.l-DOPA methyl ester did not affect the inhibitory action ofl-DOPA on the fast EPSPs, but antagonized the potentiation following the inhibition. The depolarization elicited by exogenously applied. ACh was inhibited by 10 μMl-DOPA. Intracellular Ca2+ concentrations ([Ca2+]i) of the neuronal soma were measured with fura-2 microfluorophotometry. The transient increase in the [Ca2+]i evoked by the somatic action potential (Δ[Ca2+]AP) was facilitated by 30 nMl-DOPA, but decreased by the drug at 10 μM. It is concluded thatl-DOPA at low concentrations enhances the Δ[Ca2+]AP, increasing the neurotransmitter release, but at high dose diminishes the Δ[Ca2+]AP, inhibiting the neurotransmission. 相似文献