全文获取类型
收费全文 | 13335篇 |
免费 | 563篇 |
国内免费 | 151篇 |
专业分类
耳鼻咽喉 | 166篇 |
儿科学 | 215篇 |
妇产科学 | 116篇 |
基础医学 | 1495篇 |
口腔科学 | 356篇 |
临床医学 | 841篇 |
内科学 | 3555篇 |
皮肤病学 | 237篇 |
神经病学 | 872篇 |
特种医学 | 477篇 |
外科学 | 2789篇 |
综合类 | 49篇 |
预防医学 | 302篇 |
眼科学 | 207篇 |
药学 | 816篇 |
中国医学 | 16篇 |
肿瘤学 | 1540篇 |
出版年
2023年 | 93篇 |
2022年 | 169篇 |
2021年 | 337篇 |
2020年 | 192篇 |
2019年 | 219篇 |
2018年 | 293篇 |
2017年 | 231篇 |
2016年 | 295篇 |
2015年 | 314篇 |
2014年 | 419篇 |
2013年 | 532篇 |
2012年 | 801篇 |
2011年 | 858篇 |
2010年 | 479篇 |
2009年 | 421篇 |
2008年 | 746篇 |
2007年 | 780篇 |
2006年 | 793篇 |
2005年 | 875篇 |
2004年 | 800篇 |
2003年 | 758篇 |
2002年 | 736篇 |
2001年 | 231篇 |
2000年 | 237篇 |
1999年 | 236篇 |
1998年 | 221篇 |
1997年 | 158篇 |
1996年 | 150篇 |
1995年 | 103篇 |
1994年 | 103篇 |
1993年 | 96篇 |
1992年 | 145篇 |
1991年 | 135篇 |
1990年 | 129篇 |
1989年 | 120篇 |
1988年 | 113篇 |
1987年 | 92篇 |
1986年 | 73篇 |
1985年 | 86篇 |
1984年 | 49篇 |
1983年 | 46篇 |
1982年 | 26篇 |
1981年 | 24篇 |
1979年 | 30篇 |
1978年 | 30篇 |
1975年 | 26篇 |
1971年 | 23篇 |
1970年 | 22篇 |
1969年 | 24篇 |
1967年 | 23篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
41.
F. F. Isik T. O. McDonald M. Ferguson E. Yamanaka D. Gordon 《The American journal of pathology》1992,141(5):1139-1149
Transplant arteriosclerosis (TA) has emerged as an obstacle to the long-term survival of transplanted organs, especially cardiac transplants. The animal models that have been used to study TA have not been fully characterized with regard to features such as the time course of cell proliferation and the sequence of cell types arriving in the developing intimal lesion. We present a model of TA based on a transplanted segment of abdominal aorta that helps address these questions. Two strains of rats (PVG x DA) underwent orthotopic aortic transplantation without immunosuppression and were killed at 14, 20, 40, and 60 days after transplantation. The within-strain control group displayed minimal evidence of cellular rejection with minimal to absent intimal lesions. In contrast, the allograft group showed a linearly increasing intimal lesion, up through 60 days after transplantation. The mechanism of intimal thickening was by an increase in cell number at the earlier time points with the later deposition of extracellular matrix. The early intimal lesion consisted mostly of mononuclear inflammatory cells (45%) with gradually increasing presence of smooth muscle cells (SMC) in the intima between 20 and 60 days. Conversely, the media showed gradual infiltration by macrophage-type cells with virtual loss of all SMC from the media by 40 days. The proliferative index showed a peak of 6% and 8% at 20 days in both the intima and media, respectively, and was preceded by the presence of macrophages. In fact, most of the proliferating cells at the earlier time points were either monocytes/macrophages, or were immediately adjacent to monocyte-/macrophage-rich regions. This straight artery segment model of transplant arteriosclerosis provides an easily quantifiable system in which the effects of different interventions (e.g., immunosuppressive regimens) can be tested. 相似文献
42.
43.
Keiko Nawata Hiromi Ishida Naoko Yamashita Kazuhiro Uenishi 《SANGYO EISEIGAKU ZASSHI》2006,48(5):176-182
The present study examined the relationship between number of steps and body mass index (BMI) among male workers in the metropolitan area. The number of subjects were 310 (aged 30-59) and they were studied for seven consecutive days. The number of steps was measured by a pedometer. Energy expenditure was assessed by the activity record method. Energy intake was assessed by a food frequency questionnaire. Height and body weight were examined by a self-administered questionnaire. BMI of 81 subjects (26.1%) was greater than 25 kg/m2. The number of steps was 10,682 +/- 4,365 on working days, and 7,135 +/- 4,536 on holidays. Average energy expenditure in seven days was 2,259 +/- 378 kcal/d. The physical activity level (PAL) was 1.5 +/- 0.1. There was a significant correlation between BMI and the number of steps in a working day (r=-0.188, p<0.01). In addition, there were significant correlations between PAL and daily steps on working days (r=0.301, p<0.001), and on holidays (r=0.296, p<0.001). Subjects were divided into four groups according to the median number of steps on working days and energy intake (I; > or =9,894 steps, <1,901 kcal, II; > or =9,894 steps, > or =1,901 kcal, III; <9,894 steps, <1,901 kcal, IV; <9,894 steps, > or =1,901 kcal). BMI of Group IV (24.7 kg/m2) was significantly higher than that of the other Groups. Group III had the highest proportion of subjects (15.7%) with lifestyle related diseases. 相似文献
44.
Tomomi Iwashita Kazuo Kitazawa Jun-Ichi Koyama Hisashi Nagashima Toru Koyama Yuichiro Tanaka Kazuhiro Hongo Hiroshi Okudera Kazufumi Okamoto 《Journal of clinical neuroscience》2007,14(1):68-71
A patient with cerebral deep sinus thrombosis, which was not diagnosed on the first examination, is reported. A 46-year-old woman presented with headache and vomiting. Neurological examination and a brain computed tomography (CT) scan showed no obvious abnormal findings. The patient suffered disturbed consciousness on the day after the examination, and was admitted to our emergency centre. A CT scan and magnetic resonance imaging revealed an ischaemic lesion in the left basal ganglia, suggesting deep sinus occlusion. Anticoagulant therapy was administered. One day after admission, a CT scan showed a haematoma and severe brain swelling in the same region. Cerebral angiography demonstrated a straight sinus occlusion. Intracranial pressure was not controlled with hypothermia, and the patient died 25 days after admission. Review of the initial CT scan revealed subtle, early findings of deep venous thrombosis that were missed on first examination. 相似文献
45.
Yuji Katayama Naoki Minato Masayuki Sakaguchi Atsushi Nakashima Kazuhiro Hisajima 《Annals of thoracic and cardiovascular surgery》2005,11(6):419-423
Pseudoaneurysm is an uncommon and serious complication of infective endocarditis (IE). It is often fatal because of its rapid progress, high rates of rupture and recurrence, and worsening effects on the systemic condition. We report the rare case of a patient who developed a pseudoaneurysm of the sinus of Valsalva two months after emergency aortic valve replacement for active IE. At the previous operation, we had directly closed a small fistulous hole in the non-coronary sinus of Valsalva using two mattress sutures with autologous pericardial pledgets, because the tissue surrounding the hole did not appear to be infected on visual inspection. A pseudoaneurysm developed from this portion due to detachment of sutures. If the fistula had been completely resected during the first surgery instead of performing a simple closure, the pseudoaneurysm of the sinus of Valsalva would not have formed. However, the primary aim of the first emergency surgery was to spare the life of a critically ill patient. In the second surgery, the pseudoaneurysm was completely resected with the aortic wall--including the non-coronary sinus of Valsalva and the communicating hole. Then, patch plasty of the non-Valsalva sinus was successfully performed. 相似文献
46.
Keiko Imamura Kenji Wada Kenichi Yasui Kazuhiro Nakaso Yasuhiro Watanabe Hisanori Kowa Kenji Nakashima 《Clinical neurology》2004,44(7):446-449
A 61-year-old man had been treated for malignant fibrous histiocytoma with the pulmonary and the lymph node metastasis in the department of orthopedics in our hospital. He was admitted to our department because of an acute onset of conscious disturbance and non-fluent aphasia. Diffusion-weighted imaging (DWI) showed high signal intensity areas in the bilateral cerebella, thalami and posterior lobes. T2WI did not show any mass effects. Enhanced CT did not reveal any enhanced lesion. He was diagnosed as having cerebral embolism, and his conscious disturbance was improved after medication. Eight weeks later, he presented dysphagia, dysarthria, and ataxia in his extremities. DWI showed multiple lesions of low signal intensity located at the identical place where had showed high signal intensity in the initial DWI. T2WI showed high signal intensity area with mass effect. It was indicated that cerebral metastasis might grow after tumorgenic embolism. This is a rare case that tumor emboluses were developed to the metastatic brain tumors. 相似文献
47.
Shuichiro Uchiyama Kazuo Chijiiwa Masahide Hiyoshi Motoaki Nagano Jiro Ohuchida Koki Nagaike Masahiro Kai Kazuhiro Kondo 《Journal of gastrointestinal surgery》2007,11(11):1570-1572
Mucin-producing tumor in the bile duct is referred to clinically as mucin-producing bile duct tumor (MPBT). Intraductal papillary
neoplasm of the biliary tract that resembles an intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a rare category
of MPBT and is not well characterized. We, herein, report a case of MPBT of the caudate lobe of the liver that showed papillary
growth and communicated with the bile duct of the caudate lobe and protruded into the common hepatic duct. Histologically,
MPBT cells showed papillary overgrowth with abundant mucinous secretions, resembling an IPMN of the pancreas. The MPBT cells
showed the same immunostaining pattern as that of cells from IPMN of the pancreas. 相似文献
48.
Masaaki Kohta Hiroaki Minami Kazuhiro Tanaka Keiichi Kuwamura Takeshi Kondoh Eiji Kohmura 《Journal of clinical neuroscience》2007,14(2):167-170
A 52-year-old man fell from standing and a computed tomography (CT) scan revealed traumatic intracerebral haematoma and subarachnoid haemorrhage in the temporal cortex. He was treated without surgery and discharged. On day 30 after the accident, he had no neurological deficit. On day 37 he complained of headache and urinary incontinence, and on day 39 he was hospitalized due to progressive neurological deterioration (reduced conciousness, dilated pupils, and left hemiplegia). A CT scan revealed a diffuse low-density in the right cerebral hemisphere with marked midline shift. Emergency decompressive craniectomy and right temporal lobectomy were performed. Angiography after surgery revealed moderate vasospasm in the right middle and anterior cerebral arteries. The patient remained severely disabled. Delayed onset neurological deterioration can be caused by brain oedema and vasospasm after traumatic brain injury, despite an intervening period of improvement. 相似文献
49.
50.
Takao Kamezaki Kiyoyuki Yanaka Keishi Fujita Kazuhiro Nakamura Yasushi Nagatomo Tadao Nose 《Journal of clinical neuroscience》2004,11(3):311-313
Subdural hygroma is a frequent delayed complication of head trauma. Most hygromas are clinically 'silent' and a few cases have shown slow deterioration in the chronic stage. We report a case of subdural hygroma showing unique radiological findings and rapid deterioration. A 74-years-old female presented with a mild headache and consciousness disturbance after head injury. Computed tomography showed a midline shift as a result of two components piling up in the subdural space; the outer components showed low density, the inner components high density. Magnetic resonance imaging demonstrated that these two subdural components were subdural hygroma and subarachnoid hematoma. Simple burr hole irrigation, rather than large craniotomy, was thought to be more appropriate treatment to reduce the mass effect. Simple burr hole irrigation was performed to remove the subdural hygroma and the patient showed an excellent recovery. Careful examination of the radiological findings prevented an unnecessary procedure in this case. A possible mechanism of this phenomenon is discussed. 相似文献