全文获取类型
收费全文 | 6401篇 |
免费 | 334篇 |
国内免费 | 72篇 |
专业分类
耳鼻咽喉 | 64篇 |
儿科学 | 189篇 |
妇产科学 | 88篇 |
基础医学 | 784篇 |
口腔科学 | 216篇 |
临床医学 | 390篇 |
内科学 | 1627篇 |
皮肤病学 | 158篇 |
神经病学 | 293篇 |
特种医学 | 350篇 |
外科学 | 1350篇 |
综合类 | 16篇 |
预防医学 | 100篇 |
眼科学 | 53篇 |
药学 | 402篇 |
中国医学 | 9篇 |
肿瘤学 | 718篇 |
出版年
2023年 | 43篇 |
2022年 | 83篇 |
2021年 | 131篇 |
2020年 | 107篇 |
2019年 | 127篇 |
2018年 | 150篇 |
2017年 | 121篇 |
2016年 | 154篇 |
2015年 | 162篇 |
2014年 | 229篇 |
2013年 | 274篇 |
2012年 | 403篇 |
2011年 | 429篇 |
2010年 | 221篇 |
2009年 | 175篇 |
2008年 | 379篇 |
2007年 | 422篇 |
2006年 | 400篇 |
2005年 | 398篇 |
2004年 | 357篇 |
2003年 | 357篇 |
2002年 | 359篇 |
2001年 | 82篇 |
2000年 | 97篇 |
1999年 | 78篇 |
1998年 | 78篇 |
1997年 | 55篇 |
1996年 | 68篇 |
1995年 | 50篇 |
1994年 | 70篇 |
1993年 | 43篇 |
1992年 | 78篇 |
1991年 | 61篇 |
1990年 | 56篇 |
1989年 | 51篇 |
1988年 | 39篇 |
1987年 | 43篇 |
1986年 | 33篇 |
1985年 | 38篇 |
1984年 | 32篇 |
1983年 | 33篇 |
1982年 | 31篇 |
1981年 | 20篇 |
1980年 | 18篇 |
1979年 | 23篇 |
1978年 | 15篇 |
1977年 | 18篇 |
1975年 | 12篇 |
1974年 | 14篇 |
1972年 | 13篇 |
排序方式: 共有6807条查询结果,搜索用时 15 毫秒
1.
Heterozygous nonsense mutations near the C‐terminal region of IGF1R in two patients with small‐for‐gestational‐age‐related short stature 下载免费PDF全文
2.
Akira Sugawara Kazuhisa Takeuchi Takashi Suzuki Keiichi Itoi Hironobu Sasano Sadayoshi Ito 《Hypertension research》2003,26(8):663-668
We describe a case of aldosterone-producing adrenocortical adenoma (APA) associated with a probable post-operative adrenal crisis possibly due to subtle autonomous cortisol secretion. The patient was a 46-year-old female who suffered from severe hypertension and hypokalemia. CT and MRI scans revealed a 2-cm diameter adrenal mass. The patient's plasma aldosterone level was increased, and her plasma renin activity was suppressed, both of which findings were consistent with APA. Cushingoid appearance was not observed. Morning and midnight serum cortisol and plasma adrenocorticotropic hormone (ACTH) levels were all within the normal range. Her serum cortisol level was suppressed to 1.9 microg/dl as measured by an overnight 1-mg dexamethasone suppression test, but was incompletely suppressed (2.7 microg/dl) by an overnight 8-mg dexamethasone suppression test. In addition, adrenocortical scintigraphy showed a strong uptake at the tumor region and a complete suppression of the contra-lateral adrenal uptake. After unilateral adrenalectomy, she had an episode of adrenal crisis, and a transient glucocorticoid replacement improved the symptoms. Histopathological studies demonstrated that the tumor was basically compatible with APA. The clear cells in the tumor were admixed with small numbers of compact cells that expressed 17alpha-hydroxylase, suggesting that the tumor was able to produce and secrete cortisol. In addition, the adjacent non-neoplastic adrenal cortex showed cortical atrophy, and dehydroepiandrosterone sulfotransferase immunoreactivity in the zonae fasciculata and reticularis was markedly diminished, suggesting that the hypothalamo-pituitary-adrenal (HPA) axis of the patient was suppressed due to neoplastic production and secretion of cortisol. Together, these findings suggested that autonomous secretion of cortisol from the tumor suppressed the HPA axis of the patient, thereby triggering the probable post-operative adrenal crisis. Post-operative adrenocortical insufficiency should be considered in clinical management of patients with relatively large APA, even when physical signs of autonomous cortisol overproduction are not apparent. 相似文献
3.
4.
Changes in central dopaminergic systems with the expression of Shh or GDNF in mice perinatally exposed to bisphenol-A. 总被引:1,自引:0,他引:1
Kazuya Miyagawa Minoru Narita Michiko Narita Keiichi Niikura Hisahiko Akama Yuri Tsurukawa Tsutomu Suzuki 《Nihon shinkei seishin yakurigaku zasshi》2007,27(2):69-75
In the previous study, we reported that exposure to bisphenol-A induced the potentiation of dopamine receptor functions in the mouse limbic area, resulting in supersensitivity to methamphetamine-induced pharmacological actions. The present study was undertaken to investigate whether prenatal exposure to bisphenol-A could produce morphological change in dopaminergic neuron and the pattern of expression of genes regulating the dopaminergic neuron development. Here we found that prenatal and neonatal exposures to bisphenol-A increased the tyrosine hydroxylase- and dopamine transporter-like immunoreactivities in the adult mouse limbic area. The present molecular biological study shows that chronic bisphenol-A treatment produced a significant decrease in the dopaminergic neuron development factors, sonic hedgehog and glial cell line-derived neurotrophic factor, which were also decreased by prenatal exposure to bisphenol-A. These results suggest that chronic exposure to bisphenol-A could disrupt the dopaminergic neurotransmission in the process of dopaminergic neuron development. 相似文献
5.
6.
Kanta Kishi Michiko Muramatsu Denan Jin Keiichi Furubayashi Shinji Takai Hiroshi Tamai Mizuo Miyazaki 《Hypertension research》2007,30(1):77-83
Chymase is known to generate angiotensin II in the vascular wall. In this study we investigated a novel role for chymase other than angiotensin II production in vascular proliferation after balloon injury. Chymase promoted the migration of vascular smooth muscle cells in the matrix-coated invasion chambers and activated promatrix metalloproteinase-2 obtained from the culture medium of vascular smooth muscle cells. Two weeks after balloon injury, significant neointimal formation was found in dog carotid arteries. After injury, active matrix metalloproteinase-2 was increased in parallel with the augmentation of chymase activity that was seen in the proliferating region of the vascular wall. The oral administration of NK3201 (1 mg/kg per day), a chymase inhibitor, prevented neointimal formation and significantly suppressed both active matrix metalloproteinase-2 and chymase activities 2 weeks after injury. These results suggest that chymase inhibitors can prevent the development of intimal hyperplasia via the inhibition of matrix metalloproteinase-2 activation in balloon-injured arteries. 相似文献
7.
Plaque composition and its relationship with acknowledged shear stress patterns in coronary arteries. 总被引:2,自引:0,他引:2
8.
Relation of inflammatory cytokines to atrial fibrillation after off-pump coronary artery bypass grafting. 总被引:5,自引:0,他引:5
Keiichi Ishida Fumio Kimura Mizuho Imamaki Atsushi Ishida Hitoshi Shimura Hiroki Kohno Manabu Sakurai Masaru Miyazaki 《European journal of cardio-thoracic surgery》2006,29(4):501-505
OBJECTIVE: It has been observed that a systemic inflammatory response after on-pump coronary artery bypass grafting (CABG) participates in the pathogenesis of postoperative atrial fibrillation (AF). In patients undergoing off-pump CABG, it is plausible that inflammation is associated with the development of postoperative AF. The present study examined relation of proinflammatory cytokines, which play an important role in the upstream of inflammatory cascade, to the development of AF after off-pump CABG. METHODS: The present study included 39 patients undergoing off-pump CABG. Tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-6, and IL-8, were measured by enzyme-linked immunosorbent assay, on anesthetic induction, after sternotomy before anastomoses, at the completion of anastomoses, 3 and 6h thereafter, and on postoperative days (POD) 1-4. C-reactive protein (CRP) was also measured by turbidimetric immunoassay, preoperatively, and on POD 1, 2, 3, 6, 9, and 13. RESULTS: Eleven patients (28%) developed postoperative AF. Patients with postoperative AF were older (70+/-6.4 years vs 60+/-8.8 years, P=0.001); however, there was no difference in other pre- and perioperative variables. TNF-alpha level did not change during the study period. However, IL-8 and CRP levels significantly increased after the surgery, although there was no significant difference between the two groups. IL-6 level also increased after the surgery with its peak at 6h after the completion of anastomoses. IL-6 levels of 3 and 6h after anastomoses were significantly higher in patients with postoperative AF (360+/-143 pg/ml vs 230+/-94 pg/ml, P=0.0047, 435+/-175 pg/ml vs 247+/-102 pg/ml, P=0.0005, respectively). Logistic regression analysis indicated that the highest quartile of IL-6 level immediately after the surgery (odds ratio 7.63; 95% CI, 1.06-54.9; P=0.04) and age (odds ratio 1.18; 95% CI, 1.01-1.39; P=0.04) independently predict postoperative AF. Furthermore, the maximum level of IL-6 immediately after the surgery significantly correlated to age and intraoperative blood loss (r=0.04, P=0.01, and r=0.47, P=0.04, respectively). CONCLUSIONS: Advanced age was a major risk factor for postoperative AF. Furthermore, inflammatory response induced by surgical trauma was also associated with the development of AF after off-pump CABG. 相似文献
9.
Kazuhiko Kyoshima Susumu Oikawa Miki Kanaji Hideo Zenisaka Takeomi Takizawa Tetsuya Goto Hisayoshi Takasawa Atsushi Watanabe Kazuo Tokushige Keiichi Sakai 《Journal of clinical neuroscience》2003,10(5):571-578
Some chordomas have a very poor prognosis because of their aggressive growth nature, but the efficacy of repeat operations for these cases has not been well documented. This report concerns 3 patients with aggressive chordoma of the clivus, who underwent operations 6 to 12 times over a period of 8 to 17 years because of symptomatic regrowth. Overall mean interval between repeat operations was 18 months with a range from 5 to 57 months and survival times were 9 to19 years after the first surgery. Main symptoms before each operation were diplopia and visual disturbance. Repeat palliative operations by intentional extradural debulking of the tumour to decompress offending neural structures, as well as maximal removal of the tumour, using appropriate skull base approaches, can mitigate progressive symptoms, and may result in better quality and some prolongation of life, although our patients gradually deteriorated neurologically throughout the clinical course. 相似文献
10.