全文获取类型
收费全文 | 4660篇 |
免费 | 208篇 |
国内免费 | 33篇 |
专业分类
耳鼻咽喉 | 47篇 |
儿科学 | 83篇 |
妇产科学 | 34篇 |
基础医学 | 635篇 |
口腔科学 | 82篇 |
临床医学 | 279篇 |
内科学 | 1236篇 |
皮肤病学 | 82篇 |
神经病学 | 417篇 |
特种医学 | 166篇 |
外科学 | 829篇 |
综合类 | 30篇 |
预防医学 | 89篇 |
眼科学 | 75篇 |
药学 | 341篇 |
中国医学 | 12篇 |
肿瘤学 | 464篇 |
出版年
2023年 | 26篇 |
2022年 | 53篇 |
2021年 | 69篇 |
2020年 | 48篇 |
2019年 | 52篇 |
2018年 | 76篇 |
2017年 | 55篇 |
2016年 | 96篇 |
2015年 | 73篇 |
2014年 | 119篇 |
2013年 | 126篇 |
2012年 | 250篇 |
2011年 | 276篇 |
2010年 | 158篇 |
2009年 | 143篇 |
2008年 | 256篇 |
2007年 | 316篇 |
2006年 | 256篇 |
2005年 | 287篇 |
2004年 | 304篇 |
2003年 | 277篇 |
2002年 | 300篇 |
2001年 | 120篇 |
2000年 | 114篇 |
1999年 | 112篇 |
1998年 | 58篇 |
1997年 | 56篇 |
1996年 | 43篇 |
1995年 | 49篇 |
1994年 | 41篇 |
1993年 | 39篇 |
1992年 | 67篇 |
1991年 | 62篇 |
1990年 | 54篇 |
1989年 | 56篇 |
1988年 | 45篇 |
1987年 | 46篇 |
1986年 | 49篇 |
1985年 | 43篇 |
1984年 | 33篇 |
1983年 | 22篇 |
1982年 | 16篇 |
1981年 | 23篇 |
1980年 | 23篇 |
1979年 | 11篇 |
1974年 | 10篇 |
1973年 | 15篇 |
1972年 | 8篇 |
1970年 | 9篇 |
1969年 | 9篇 |
排序方式: 共有4901条查询结果,搜索用时 31 毫秒
101.
102.
103.
104.
105.
Motohiro Hirao Hideyasu Omiya Koji Takami Kazuyoshi Yamamoto Kazuhiro Nishikawa Masataka Ikeda Atsushi Miyamoto Naoki Hama Masakazu Miyake Mamoru Uemura Sakae Maeda Shoji Nakamori Mitsugu Sekimoto 《Esophagus》2016,13(2):163-166
Background and objective
Pulmonary metastasectomy is a standard therapy for some types of metastatic lesions in the lung. Although the prognosis for esophageal cancer patients with pulmonary metastasis is poor, it has been reported that some post-esophagectomy patients have good prognosis after pulmonary metastasectomy. We investigated the role of resecting pulmonary metastases arising from esophageal cancer at our institution.Patients and methods
Seven patients with primary squamous cell carcinoma or adenocarcinoma of the thoracic esophagus who underwent resection of metachronous pulmonary metastases at our institution between 2006 and 2012 were identified from a retrospective database. All patients had undergone curative resection of their primary esophageal carcinoma.Results
Six patients had unilateral and solitary lung metastasis. One patient presented with one metastatic lesion on each side, and he underwent 4 metastasectomy for pulmonary metastasis 3 times. There was no perioperative morbidity or mortality. The disease-free interval after esophagectomy ranged from 191 to 559 days (median, 463 days). Survival after pulmonary metastasectomy ranged from 357 to 3191 days (median, 1803 days). Three patients received systemic chemotherapy before metastasectomy. Currently, 5 patients are alive without evidence of recurrent disease.Conclusion
Pulmonary metastasectomy may be acceptable as a part of multimodal treatment for solitary metachronous pulmonary metastasis in esophageal carcinoma.106.
Captopril improves impaired endothelium-dependent vasodilation in hypertensive patients. 总被引:7,自引:0,他引:7
Y Hirooka T Imaizumi H Masaki S Ando S Harada M Momohara A Takeshita 《Hypertension》1992,20(2):175-180
Animal studies suggest that some angiotensin converting enzyme inhibitors augment endothelium-dependent vasorelaxation. We aimed to determine if captopril augments endothelium-dependent vasodilation in middle-aged hypertensive patients. By using strain-gauge plethysmography, forearm vasodilation evoked with intra-arterial acetylcholine (4, 8, 16, and 24 micrograms/min) or nitroprusside (0.2, 0.4, 0.8, and 1.2 micrograms/min) was examined before and after captopril administration (25 mg per os). Before captopril, forearm vasodilation with acetylcholine was less in hypertensive patients (n = 12) than in age-matched (n = 7) or young (n = 7) normotensive subjects, but forearm vasodilation with nitroprusside did not differ among the three groups. Captopril improved forearm vasodilation in hypertensive patients (n = 7) with acetylcholine but nitroprusside did not. In contrast, nifedipine (10 mg per os) did not alter forearm vasodilation with acetylcholine or nitroprusside in hypertensive patients (n = 5). The decreases in mean blood pressure caused by captopril and nifedipine in hypertensive subjects were comparable. Captopril did not alter forearm vasodilation with acetylcholine or nitroprusside in young normotensive subjects (n = 7). These results suggest that captopril in hypertensive patients may acutely improve impaired endothelium-dependent forearm vasodilation that does not result from reduction in blood pressure per se. 相似文献
107.
Attenuated forearm vasodilative response to intra-arterial atrial natriuretic peptide in patients with heart failure 总被引:2,自引:0,他引:2
Y Hirooka A Takeshita T Imaizumi S Suzuki M Yoshida S Ando M Nakamura 《Circulation》1990,82(1):147-153
It has been shown that renal responses to atrial natriuretic peptide (ANP) are markedly attenuated in patients with heart failure. This study aimed to determine if vasodilative response to ANP is altered in patients with heart failure. In patients with heart failure (n = 7) and age-matched normal subjects (n = 7), forearm blood flow was measured using a strain-gauge plethysmograph during intra-arterial infusion of alpha-human ANP (50, 100, 200, and 400 ng/min) or nitroglycerin (100, 200, 400, and 600 ng/min). Forearm vasodilatation evoked with intra-arterial alpha-human ANP in patients with heart failure was considerably less (p less than 0.01) than that in normal subjects. In contrast, nitroglycerin produced comparable forearm vasodilatation in the two groups. Plasma ANP and cyclic guanosine monophosphate (GMP) levels at rest were higher in patients with heart failure than in normal subjects (p less than 0.05 for both), but the increases in plasma ANP and cyclic GMP in the venous effluents during intra-arterial ANP infusion did not differ between the two groups. These results indicate that the direct vasodilative effect of ANP on forearm vessels was attenuated in patients with heart failure as compared with that in normal subjects. The mechanisms responsible for this alteration are not clear but might involve mechanisms other than down-regulation of the ANP receptors because the increases in venous plasma cyclic GMP caused by intra-arterial ANP were comparable between patients with heart failure and normal subjects. 相似文献
108.
Gonadotropin-inhibitory hormone neurons interact directly with gonadotropin-releasing hormone-I and -II neurons in European starling brain 总被引:3,自引:0,他引:3
Ubuka T Kim S Huang YC Reid J Jiang J Osugi T Chowdhury VS Tsutsui K Bentley GE 《Endocrinology》2008,149(1):268-278
Gonadotropin-inhibitory hormone (GnIH) is a hypothalamic dodecapeptide (SIKPSAYLPLRF-NH(2)) that directly inhibits gonadotropin synthesis and release from quail pituitary. The action of GnIH is mediated by a novel G-protein coupled receptor. This gonadotropin-inhibitory system may be widespread in vertebrates, at least birds and mammals. In these higher vertebrates, histological evidence suggests contact of GnIH immunoreactive axon terminals with GnRH neurons, thus indicating direct regulation of GnRH neuronal activity by GnIH. In this study we investigated the interaction of GnIH and GnRH-I and -II neurons in European starling (Sturnus vulgaris) brain. Cloned starling GnIH precursor cDNA encoded three peptides that possess characteristic LPXRF-amide (X = L or Q) motifs at the C termini. Starling GnIH was further identified as SIKPFANLPLRF-NH(2) by mass spectrometry combined with immunoaffinity purification. GnIH neurons, identified by in situ hybridization and immunocytochemistry (ICC), were clustered in the hypothalamic paraventricular nucleus. GnIH immunoreactive fiber terminals were present in the external layer of the median eminence in addition to the preoptic area and midbrain, where GnRH-I and GnRH-II neuronal cell bodies exist, respectively. GnIH axon terminals on GnRH-I and -II neurons were shown by GnIH and GnRH double-label ICC. Furthermore, the expression of starling GnIH receptor mRNA was identified in both GnRH-I and GnRH-II neurons by in situ hybridization combined with GnRH ICC. The cellular localization of GnIH receptor has not previously been identified in any vertebrate brain. Thus, GnIH may regulate reproduction of vertebrates by directly modulating GnRH-I and GnRH-II neuronal activity, in addition to influencing the pituitary gland. 相似文献
109.
Ozaki K Oda H Suzuki T Ohno Y Tsuchida K Takahashi K Miida T 《Journal of cardiology》2008,51(1):70-73
A 69-year-old woman underwent percutaneous coronary intervention for a severe stenotic lesion in the bifurcation of the mid-left anterior descending artery and first diagonal branch. A single stent was implanted into the left anterior descending artery. After the stent strut was dilated by balloon inflation in the diagonal branch, dissection occurred at the ostium of the diagonal branch and resulted in side branch occlusion due to hematoma. Bailout stenting was performed in the diagonal branch, but thrombus projection occurred in the left anterior descending artery. Aspiration, balloon inflation and thrombolytic therapy were performed, but distal embolism developed. This case illustrates that thrombus projection caused by stenting in a side branch may occur as a rare complication in percutaneous coronary intervention. 相似文献
110.
BACKGROUND: The use of methylene blue chromoendoscopy in the diagnosis of specialized intestinal metaplasia in short-segment Barrett's esophagus is controversial. This study evaluated the use of magnifying endoscopy with methylene blue for this purpose. METHODS: A total of 30 patients (21 men, 9 women; median age 61 years, range 32-79 years) with short lengths of columnar-lined esophagus were enrolled in a prospective trial of magnifying endoscopy with methylene blue in which the appearance after methylene blue staining was used to target biopsy specimens. Patients were screened for Helicobacter pylori infection, and only those without infection were enrolled (because many Japanese patients have pan-gastritis caused by H pylori infection, and intestinal metaplasia distal to the squamocolumnar junction may be secondary to H pylori-induced gastritis). All biopsy specimens were stained with H and E; MUC2 immunostaining was used to identify specialized intestinal metaplasia. RESULTS: Thirty patients with short-segment columnar-lined esophagus underwent magnifying endoscopy with methylene blue. Ninety-three biopsy specimens were obtained, 33 from methylene blue-stained areas and 60 from unstained areas, each about 7 mm from the marginal edge of stained areas. Specialized intestinal metaplasia was confirmed in biopsy specimens from 28 of the 33 stained areas (sensitivity 84.8%); in biopsy specimens from 55 of the 60 unstained areas, specialized intestinal metaplasia was not found (specificity 91.7%). In magnified views of methylene blue-positive areas, a tubular, cavernous, or elliptical pattern was seen. Sixteen of 21 men (76.2%) and 3 of 9 women had specialized intestinal metaplasia, and short-segment Barrett's esophagus was diagnosed in these patients. Even in patients with less than 1 cm of columnar-lined esophagus, 8 of 10 stained areas contained specialized intestinal metaplasia (sensitivity 80%) and 23 of 24 unstained areas did not (specificity 95.8%). Six of 12 patients (50%) with less than 1 cm of columnar-lined esophagus had specialized intestinal metaplasia. In total, 19 of 30 patients had specialized intestinal metaplasia. CONCLUSIONS: Magnifying endoscopy with methylene blue selectively detects specialized intestinal metaplasia within short-segment columnar-lined esophagus. 相似文献