全文获取类型
收费全文 | 26111篇 |
免费 | 1330篇 |
国内免费 | 147篇 |
专业分类
耳鼻咽喉 | 256篇 |
儿科学 | 508篇 |
妇产科学 | 369篇 |
基础医学 | 3205篇 |
口腔科学 | 596篇 |
临床医学 | 1718篇 |
内科学 | 6884篇 |
皮肤病学 | 1080篇 |
神经病学 | 1930篇 |
特种医学 | 781篇 |
外科学 | 4353篇 |
综合类 | 89篇 |
一般理论 | 4篇 |
预防医学 | 663篇 |
眼科学 | 513篇 |
药学 | 1590篇 |
中国医学 | 62篇 |
肿瘤学 | 2987篇 |
出版年
2023年 | 123篇 |
2022年 | 244篇 |
2021年 | 516篇 |
2020年 | 282篇 |
2019年 | 384篇 |
2018年 | 509篇 |
2017年 | 428篇 |
2016年 | 476篇 |
2015年 | 500篇 |
2014年 | 664篇 |
2013年 | 762篇 |
2012年 | 1284篇 |
2011年 | 1316篇 |
2010年 | 874篇 |
2009年 | 740篇 |
2008年 | 1288篇 |
2007年 | 1394篇 |
2006年 | 1465篇 |
2005年 | 1505篇 |
2004年 | 1459篇 |
2003年 | 1421篇 |
2002年 | 1401篇 |
2001年 | 756篇 |
2000年 | 741篇 |
1999年 | 734篇 |
1998年 | 339篇 |
1997年 | 255篇 |
1996年 | 260篇 |
1995年 | 208篇 |
1994年 | 160篇 |
1993年 | 176篇 |
1992年 | 452篇 |
1991年 | 396篇 |
1990年 | 404篇 |
1989年 | 421篇 |
1988年 | 390篇 |
1987年 | 341篇 |
1986年 | 340篇 |
1985年 | 281篇 |
1984年 | 232篇 |
1983年 | 172篇 |
1982年 | 85篇 |
1979年 | 146篇 |
1978年 | 110篇 |
1977年 | 108篇 |
1974年 | 105篇 |
1973年 | 86篇 |
1972年 | 96篇 |
1971年 | 85篇 |
1970年 | 87篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
21.
Joe Matsumoto Tetsufumi Kojima Tetsuya Shimizu Shuji Kitashiro Kazuya Konishi Yoshiyuki Matsumura You Kawarada Hitoshi Ikeda Takashi Yoshiki 《Annals of thoracic and cardiovascular surgery》2002,8(3):151-153
In lung cancer patients, hypercalcemia is a fairly common metabolic problem associated with malignancy. However, the occurrence of hypercalcemia in lung cancer patients means an ominous prognostic sign. As hypercalcemia often causes early death, quick diagnosis and treatment for hypercalcemia are required. A 69-year-old woman was admitted to our hospital with anorexia caused by hypercalcemia. On admission, serum level of PTH was elevated and PTHrP was normal. From the results of CT findings and transbronchial lung biopsy, the cause of the hypercalcemia was determined as lung cancer incidentally complicated with primary hyperparathyroidism. First, serum calcium level was returned to normal through hydration with saline and bisphosphonates. Next, left hemithyroidectomy for primary hyperparathyroidism was performed. Histologically, the tumor was diagnosed as parathyroid adenoma. Fifteen days later, left lower lobectomy for primary lung cancer was performed under a video-assisted thoracoscopic approach. Histologically, the tumor was diagnosed as a moderately differentiated adenocarcinoma. Four years and three months after the operation, the patient is alive and well with no sign of recurrence. When a lung cancer patient is complicated with hypercalcemia, we need to consider that primary hyperparathyroidism is a possible cause of the hypercalcemia. 相似文献
22.
K Hatakeyama M Aihara A Shimizu N Uchida T Inukai 《No to hattatsu. Brain and development》1991,23(1):76-80
Higher cerebral dysfunctions such as aphasia, apraxia and agnosia have seldom been reported in multiple sclerosis (MS). 12 year-old right-handed boy felt unsteadiness of the body and headache for several days. Two months later, he had the same episode and complained of visual disturbance, and weakness and sensory disturbance on the face and the extremities. Additionally, he showed amnestic aphasia, acalculia, ideomotor apraxia, finger agnosia and right-left disorientation. Cerebrospinal fluid examinations revealed increases IgG, myelin basic protein and neuron specific enolase (11%, 25 ng/ml and 28.8 ng/ml, respectively). X-ray CT scan and MRI-CT examinations revealed sclerotic lesions on the left parietal white matter and the right mid-brain. The diagnosis was made as MS. He was treated with m-PSL (methyl-prednisolone) pulse therapy for three weeks and consecutively treated with PSL for four weeks. He recovered gradually, but visual disturbance and facial palsy remained. After seven months MRI-CT showed a high signal intensity on the left parietal white matter in spite of the disappearance of the lesion on X-ray CT scan. We suggest that these higher cerebral dysfunctions may result from the lesion of the left parietal white matter which produces a disconnection between each cortical area. 相似文献
23.
To clarify when and how rapidly individual muscles are damaged in the course of Duchenne muscular dystrophy (DMD), we followed X-ray CT of whole body skeletal muscles from 29 cases of DMD patients (age ranging 3 to 23 years) for a period of 2 to 6 years. Each patient had 2 to 5 scans with an average of 3.3. We evaluated chronological changes of 23 muscles from the entire body using the muscle damage stage defined as follows. The stages were classified into the following 5 stages: stage 0; normal, 1; area of fatty replacement less than 10% of whole muscle area, 2; area of fatty replacement between 10 to 50%, 3; area of fatty replacement 50 to 90%, 4; almost complete fatty replacement. Each muscle had its own period of rapid degeneration starting at 5 to 10 years of age and, continuing 5 to 10 years. In some muscles such as gluteus maximus or quadriceps femoris, fatty replacement started at 5 years or earlier and progressed for five years, while other muscles such as splenius capitis, damage started much later, e.g. around 10 years of age and the progression was much slower. There was a variation of at least 5 years among individual patients in any muscle damage stage, reflecting the variability of clinical severity in each patient. On the basis of the above results we defined the whole body muscle damage index as a summation of the muscle damage stages of the following five muscles: gluteus maximus, quadriceps femoris, gracilis, medial head of gastrocnemius and splenius capitis.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
24.
25.
26.
27.
Kimiaki Hashiguchi Takato Morioka Fumiaki Yoshida Yasushi Miyagi Shinji Nagata Ayumi Sakata Tomio Sasaki 《Seizure》2007,16(3):238-247
OBJECTIVE: To investigate the correlation between scalp-recorded electroencephalographic (EEG) and electrocorticographic (ECoG) activities during ictal periods. METHODS: Simultaneous EEG and ECoG recordings with chronic subdural electrodes were performed in eight patients with partial epilepsy. RESULTS: In two cases where the ictal ECoG discharges originated in deep brain structures such as the hippocampus and interhemispheric surface of the frontal lobe, ictal discharges could not be detected on EEG until they expanded to the cortex of convexity. In four cases, the ictal onset zones were located in the lateral convexity. When synchronous or near synchronous ictal ECoG discharges with amplitudes of 200-2000muV were recorded on more than 8-15cm(2) of cortex, corresponding discharges were recorded on EEG in these four cases. However, in a case of frontal lobe epilepsy, asynchronous ictal ECoG discharges were recorded on 10 electrodes of convexity but no ictal EEG activity was recorded. Furthermore, in two frontal lobe epilepsy cases, ictal EEG discharges did not always reflect the ictal ECoG spike, but occasionally reflected slow background ECoG activity around the ictal discharges. CONCLUSIONS: Multiple factors such as the width of the cortical area involved, amplitude of ictal discharges and degree of synchronization of electrical potentials play important roles in the appearance of ictal EEG recordings, and the relationship between ictal EEG and ECoG is not straightforward. 相似文献
28.
29.
Effect of the free radical scavenger MCI-186 on spinal cord reperfusion after transient ischemia in the rabbit 总被引:4,自引:0,他引:4
Kenichi Hashizume Toshihiko Ueda Hideyuki Shimizu Atsuo Mori Ryohei Yozu 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(8):426-433
Objective: Paraplegia remains a serious complication of aortic operations. The production of free radicals during reperfusion
after transient ischemia is believed to induce secondary spinal neuronal injury, resulting in paraplegia. The aim of the present
study was to clarify the protective effect and method of administration of antioxidants on the neurological and histological
outcome in the animal model for reperfusion injury after transient spinal cord ischemia. Methods: New Zealand white rabbits underwent surgical exposure of the abdominal aorta that was clamped for 15 minutes to achieve spinal
cord ischemia. Group A animals received two 10 mg/kg doses of 3-methyl-l-phenyl-2-pyrazolin-5-one (MCI-186) at the time of
release of the aortic clamp and 30 minutes later. In group B, MCI-186, 5 mg/kg, was given three times, at the time of aorta
clamp release, 30 minutes and 12 hours later. In group C (control group), one dose of vehicle was administered. Neurological
status was assessed using modified Tarlov’s score until 168 hours after operation. Spinal cord sections were examined microscopically
to determine the extent of ischemic neuronal damage. Results: Groups A and B animals had better neurological function than group C (p(0.001). In contrast, group C animals exhibited paraplegia or paraparesis with marked neuronal necrosis. The number of surviving
neurons within examined sections of the spinal cord was significantly greater in group B than in group C (p(0.001). Conclusion: In a 15-minute ischemia-reperfusion model using rabbits, systemic repetitious administration of MCI-186, a free radical scavenger,
was found to have a protective effect on the spinal cord neurons both neurologically and histologically. We postulate that
the drug minimizes the delayed neuronal cell death for reperfusion injury after transient ischemia by reducing the free radical
molecules. Moreover, it was thought that we could protect delayed neuronal cell death more effectively by administering MCI-18612
hours later. 相似文献
30.