全文获取类型
收费全文 | 2463篇 |
免费 | 80篇 |
国内免费 | 25篇 |
专业分类
耳鼻咽喉 | 17篇 |
儿科学 | 46篇 |
妇产科学 | 81篇 |
基础医学 | 324篇 |
口腔科学 | 42篇 |
临床医学 | 165篇 |
内科学 | 510篇 |
皮肤病学 | 41篇 |
神经病学 | 127篇 |
特种医学 | 63篇 |
外科学 | 483篇 |
综合类 | 18篇 |
预防医学 | 27篇 |
眼科学 | 92篇 |
药学 | 146篇 |
中国医学 | 4篇 |
肿瘤学 | 382篇 |
出版年
2023年 | 11篇 |
2022年 | 37篇 |
2021年 | 55篇 |
2020年 | 27篇 |
2019年 | 35篇 |
2018年 | 47篇 |
2017年 | 41篇 |
2016年 | 36篇 |
2015年 | 45篇 |
2014年 | 58篇 |
2013年 | 79篇 |
2012年 | 159篇 |
2011年 | 183篇 |
2010年 | 114篇 |
2009年 | 100篇 |
2008年 | 143篇 |
2007年 | 137篇 |
2006年 | 162篇 |
2005年 | 150篇 |
2004年 | 146篇 |
2003年 | 144篇 |
2002年 | 155篇 |
2001年 | 49篇 |
2000年 | 27篇 |
1999年 | 32篇 |
1998年 | 46篇 |
1997年 | 43篇 |
1996年 | 37篇 |
1995年 | 27篇 |
1994年 | 33篇 |
1993年 | 24篇 |
1992年 | 17篇 |
1991年 | 14篇 |
1990年 | 15篇 |
1989年 | 20篇 |
1988年 | 19篇 |
1987年 | 15篇 |
1986年 | 7篇 |
1985年 | 10篇 |
1984年 | 14篇 |
1983年 | 5篇 |
1982年 | 11篇 |
1981年 | 8篇 |
1980年 | 5篇 |
1979年 | 4篇 |
1978年 | 4篇 |
1977年 | 3篇 |
1974年 | 4篇 |
1937年 | 2篇 |
1917年 | 1篇 |
排序方式: 共有2568条查询结果,搜索用时 10 毫秒
31.
Matsunobu S Amanuma M Tsukuda S 《Nihon Igaku Hōshasen Gakkai zasshi. Nippon acta radiologica》2004,64(1):31-34
PURPOSE: To evaluate the image quality and vascular selectivity of MR venography of the head using an MP-RAGE technique when obtained with a body radiofrequency transmitter coil system. MATERIALS AND METHODS: A total of 24 patients were imaged with a head or body RF transmission system. Subtraction MRA was processed with 0.1 mmol Gd-DTPA administration, and signal-to-noise ratios of the vascular system were measured. Venous demonstration and selectivity were also assessed. RESULTS: MP-RAGE MR venography with a body transmission system showed almost the same signal intensity for the venous and arterial systems, resulting in nonspecific vascular demonstration, while the head transmission system showed semi-selective venograms owing to inflow-induced high signal on precontrast images. However, MRA with a body transmission system provided a 1.5- to 2.5-fold higher signal-to-noise ratios based on higher gradient performance and excellent demonstration of the head veins, especially those below the skull base. CONCLUSION: Although selective venography was difficult, MRA with a body transmission coil provided excellent vascular images of the brain. 相似文献
32.
Nogawa T Takahashi S Okano A Kawatani M Uramoto M Saito T Osada H 《The Journal of antibiotics》2012,65(3):123-128
Two new 6,6-spiroacetal polyketides, spirotoamides A (1) and B (2), were isolated from a microbial metabolite fraction library of Streptomyces griseochromogenes JC82-1223 by screening of structurally unique compounds based on a search of spectral database. The fraction library was constructed using a systematic separation method to efficiently discover new metabolites from microbial sources such as actinomycetes and fungi. The structures of 1 and 2 were elucidated by 2D-NMR and mass spectrometric measurements. They belong to a class of polyketides, and contain a 6,6-spiroacetal core structure and a carboxamide group. The biosynthetic pathway of 1 and 2 is discussed in the text. 相似文献
33.
Kunio Okuda Toshiro Nakashima Masahiko Okudaira Masayoshi Kage Yoshibumi Aida Masao Omata Hirotaka Musha Shunji Futagawa Mitsuo Sugiura Haruo Kameda 《Liver international》1981,1(4):255-263
ABSTRACT— Hepatic venograms made in 40 authentic cases of idiopathic portal hypertension (Banti's syndrome) were compared with 13 normal venograms and venograms obtained in 88 cases of cirrhosis, and analyzed in the light of the pathological changes seen in 16 postmortem liver specimens. There were frequent anastomoses between hepatic vein radicles, approximation of middle-size branches to the liver surface, reduction in the angles between the main hepatic vein and its tributaries, and difficulty in opacifying portal vein branches in wedged retrograde portography. These angiographic alterations were corroborated by gross pathological findings which comprised displacement of middle-size hepatic vein branches closer to the liver surface and their approximation among themselves, and seem to be accounted for by the disappearance of liver parenchyma secondary to the peripheral portal circulatory failure. 相似文献
34.
Effects of HMGB1 on ischemia-reperfusion injury in the rat heart 总被引:1,自引:0,他引:1
Susumu Oozawa Shuji Mori Toru Kanke Hideo Takahashi Keyue Liu Yasuko Tomono Masato Asanuma Ikuko Miyazaki Masahiro Nishibori Shunji Sano 《Circulation journal》2008,72(7):1178-1184
BACKGROUND: Coronary ischemia-reperfusion (I/R) injury causes cardiomyocyte necrosis in a multi-step process that includes an inflammatory reaction. A recent study has suggested that high-mobility group box 1 (HMGB1) is a late mediator of lethal sepsis and an early mediator of inflammation and necrosis following I/R injury. In the present study a neutralizing monoclonal antibody (mAb) for HMGB1 was used to clarify the role of HMGB1 in cardiac I/R injury. METHODS AND RESULTS: Rats underwent 30 min of left coronary artery occlusion followed by 60 min reperfusion. An intravenous injection of anti-HMGB1 mAb or control IgG was administered just before reperfusion. The infarct size was enlarged in the anti-HMGB1 mAb group in comparison with the control group (p<0.05). The treatment of anti-HMGB1 mAb significantly increased the plasma troponin-T and norepinephrine (NE) content in the heart in comparison with the control (p<0.05). Moreover, the production of dihydroxyphenylglycol was reduced in the anti-HMGB1-treated group (p<0.05). CONCLUSION: This study shows for the first time the effects of treatment with neutralizing anti-HMGB1 mAb on I/R injury in the rat heart. The findings support the novel view that I/R-induced HMGB1 may be an important factor in the modulation of interstitial NE. 相似文献
35.
Numerical chromosomal abnormality in gastric MALT lymphoma and diffuse large B-cell lymphoma 总被引:1,自引:0,他引:1
Watanobe I Takamori S Kojima K Fukasawa M Beppu T Futagawa S Hirai S 《Journal of gastroenterology》2002,37(9):691-696
Background: We investigated numerical chromosomal abnormalities, using the fluorescence in situ hybridization (FISH) method, in gastric
mucosa-associated lymphoid tissue (MALT) lymphoma and diffuse large B-cell lymphoma (DLBL). We also compared the histopathological
findings, including the presence or absence of Helicobacter pylori infection, with the analytical results. Methods: Sixteen patients who underwent operation for malignant gastric lymphoma in our department were divided into three groups:
patients with low-grade gastric MALT lymphoma (l-MALT; n = 5), those with high-grade gastric MALT lymphoma (h-MALT; n = 8), and those with DLBL (n = 3). Numerical abnormalities of chromosomes 8, 9, 12, and 17 were investigated by the FISH method, and the presence or absence
of H. pylori infection was microscopically examined. Results: Numerical abnormality was observed in chromosome 12 in 11 patients (68.8%), in chromosome 8 in 10 (62.5%), and in chromosome
17 in 5 (31.3%), showing a high frequency. H. pylori infection was detected in 80% and 50% of patients with l-MALT and h-MALT, respectively, but no H. pylori infection was observed in patients with DLBL. Conclusions: A new biological characteristic of gastric MALT lymphoma was obtained, i.e., a high frequency of numerical abnormalities
of chromosomes 12, 8, and 17. There was no correlation between the numerical chromosomal abnormalities and the clinicopathological
findings.
Received: September 5, 2001 / Accepted: February 22, 2002
Acknowledgments. We sincerely appreciate the instruction and cooperation provided by Mr. A. Furuhata, Mr. S. Nakamura, and the staff, Department
of Collaborative Pathology, Juntendo University, Tokyo, Japan.
Reprint requests to: I. Watanobe 相似文献
36.
Involvement of central metastin in the regulation of preovulatory luteinizing hormone surge and estrous cyclicity in female rats 总被引:10,自引:0,他引:10
Kinoshita M Tsukamura H Adachi S Matsui H Uenoyama Y Iwata K Yamada S Inoue K Ohtaki T Matsumoto H Maeda K 《Endocrinology》2005,146(10):4431-4436
Ovulation is caused by a sequence of neuroendocrine events: GnRH and LH surges that are induced by positive feedback action of estrogen secreted by the mature ovarian follicles. The central mechanism of positive feedback action of estrogen on GnRH/LH secretion, however, is not fully understood yet. The present study examined whether metastin, the product of metastasis suppressor gene KiSS-1, is a central neuropeptide regulating GnRH/LH surge and then estrous cyclicity in the female rat. Metastin had a profound stimulation on LH secretion by acting on the preoptic area (POA), where most GnRH neurons projecting to the median eminence are located, because injection of metastin into the third ventricle or POA increased plasma LH concentrations in estrogen-primed ovariectomized rats. Metastin neurons were immunohistochemically found in the arcuate nucleus (ARC) to be colocalized with estrogen receptors with some fibers in the preoptic area (POA) in close apposition with GnRH neuronal cell bodies or fibers. Quantitative RT-PCR has revealed that KiSS-1 and GPR54 mRNAs were expressed in the ARC and POA, respectively. The blockade of local metastin action in the POA with a specific monoclonal antibody to rat metastin completely abolished proestrous LH surge and inhibited estrous cyclicity. Metastin-immunoreactive cell bodies in the ARC showed a marked increase and c-Fos expression in the early proestrus afternoon compared with the day of diestrus. Thus, metastin released in the POA is involved in inducing the preovulatory LH surge and regulating estrous cyclicity. 相似文献
37.
Toko Maehara Kenjiro Matsumoto Kazuhide Horiguchi Makoto Kondo Satoshi Iino Shunji Horie Takahisa Murata Hirokazu Tsubone Shoichi Shimada Hiroshi Ozaki Masatoshi Hori 《British journal of pharmacology》2015,172(4):1136-1147
Background and Purpose
Post-operative ileus (POI) is induced by intestinal inflammation. Here, we aimed to clarify the effects of 5-HT3 receptor antagonists against POI.Experimental Approach
We administered three 5-HT3 receptor antagonists, ondansetron, tropisetron and palonosetron, to a mouse model of POI induced by surgical intestinal manipulation (IM). Immunohistochemistry, intestinal transit, inflammatory mediator mRNA expression and 5-HT content were measured. In some experiments, 5-HT3A receptor null mice were used.Key Results
Three 5-HT3 receptor antagonists reduced IM-induced infiltration of inflammatory CD68-positive macrophages and myeloperoxidase-stained neutrophils. Ondansetron exhibited no anti-inflammatory actions in 5-HT3A receptor null mice. Ondansetron inhibited expression of the chemokine CCL2, IL-1β, IL-6, TNF-α and iNOS mRNAs up-regulated by IM, and also ameliorated the delayed gastrointestinal transit. Peritoneal macrophages, but not most infiltrating monocyte-derived macrophages, expressed 5-HT3 receptors. IM stimulation increased the 5-HT content of peritoneal lavage fluid, which up-regulated mRNA expression of proinflammatory cytokines in peritoneal macrophages. Immunohistochemical localization of 5-HT3 receptors suggests that ondansetron suppressed expression of these mRNAs in activated peritoneal macrophages, adhering to the serosal region of the inflamed intestinal wall.Conclusion and Implications
5-HT3 receptor antagonists were anti-inflammatory, mainly targeting peritoneal macrophages expressing these receptors. They also restored the delayed gastrointestinal transit by IM. 5-HT3 receptor antagonists should be therapeutically useful agents against POI. 相似文献38.
Makoto Nishio Atsushi Horiike Hiroshi Nokihara Hidehito Horinouchi Shinji Nakamichi Hiroshi Wakui Fumiyoshi Ohyanagi Keita Kudo Noriko Yanagitani Shunji Takahashi Yasutoshi Kuboki Noboru Yamamoto Yasuhide Yamada Masaichi Abe Takashi Tahata Tomohide Tamura 《Investigational new drugs》2015,33(3):632-640
39.
Osami Honjo Masaaki Kawada Teiji Akagi Yasuhiro Kotani Kozo Ishino Shunji Sano 《Circulation journal》2007,71(4):613-616
Left ventricular (LV) retraining followed by anatomical repair would be a superior alternative in patients with congenitally corrected transposition (ccTGA) having a deconditioned morphologically left ventricle (MLV); however, LV retraining in older children is a challenging task. A retraining process of the MLV in a teenage patient with ccTGA is reported here. Cardiac catheterization at 7 years of age revealed low pressure of the MLV (33/4 mm Hg) and a LV to right ventricular pressure ratio (LVp/RVp ratio) of 0.32. The first pulmonary artery banding (PAB) was performed at 10 years of age. Although the LVp/RVp ratio reached 0.68, there was no evidence of adequate LV hypertrophy. The second PAB was performed 2 years after the initial PAB, resulting in an increase in the LVp/RVp ratio to 0.93 and an adequate LV hypertrophy. The double switch procedure was successfully performed at 13 years of age. Although the ejection fraction of the MLV mildly decreased, the patient has been doing well during a follow-up period of 4 years. The MLV in the teenage patient with ccTGA was successfully trained using a retraining strategy and has sustained systemic circulation after anatomical repair. 相似文献
40.
DNA chip, expression profile, and SNP analyses applied for clinical gastroenterology] 总被引:1,自引:0,他引:1
Shunji Mishiro 《Nihon Shokakibyo Gakkai zasshi》2004,101(2):121-126