全文获取类型
收费全文 | 13427篇 |
免费 | 616篇 |
国内免费 | 84篇 |
专业分类
耳鼻咽喉 | 106篇 |
儿科学 | 276篇 |
妇产科学 | 125篇 |
基础医学 | 1732篇 |
口腔科学 | 335篇 |
临床医学 | 820篇 |
内科学 | 3518篇 |
皮肤病学 | 183篇 |
神经病学 | 871篇 |
特种医学 | 490篇 |
外科学 | 2467篇 |
综合类 | 76篇 |
预防医学 | 339篇 |
眼科学 | 194篇 |
药学 | 795篇 |
中国医学 | 47篇 |
肿瘤学 | 1753篇 |
出版年
2023年 | 105篇 |
2022年 | 204篇 |
2021年 | 334篇 |
2020年 | 163篇 |
2019年 | 215篇 |
2018年 | 317篇 |
2017年 | 212篇 |
2016年 | 292篇 |
2015年 | 259篇 |
2014年 | 384篇 |
2013年 | 455篇 |
2012年 | 791篇 |
2011年 | 806篇 |
2010年 | 490篇 |
2009年 | 404篇 |
2008年 | 789篇 |
2007年 | 820篇 |
2006年 | 803篇 |
2005年 | 859篇 |
2004年 | 790篇 |
2003年 | 744篇 |
2002年 | 778篇 |
2001年 | 196篇 |
2000年 | 208篇 |
1999年 | 221篇 |
1998年 | 218篇 |
1997年 | 170篇 |
1996年 | 148篇 |
1995年 | 145篇 |
1994年 | 126篇 |
1993年 | 115篇 |
1992年 | 155篇 |
1991年 | 161篇 |
1990年 | 122篇 |
1989年 | 124篇 |
1988年 | 144篇 |
1987年 | 108篇 |
1986年 | 93篇 |
1985年 | 89篇 |
1984年 | 65篇 |
1983年 | 74篇 |
1982年 | 34篇 |
1981年 | 40篇 |
1980年 | 32篇 |
1979年 | 34篇 |
1978年 | 24篇 |
1977年 | 32篇 |
1973年 | 23篇 |
1972年 | 26篇 |
1970年 | 21篇 |
排序方式: 共有10000条查询结果,搜索用时 7 毫秒
51.
52.
Masahiko Kawaguchi Masakazu Kuro Hisatoshi Ohsumi Toshito Nakajima Yoshihiro Kuriyama Jun Karasawa 《Journal of anesthesia》1994,8(1):60-63
We assessed the local cerebral blood flow (LCBF) in 40 patients under fentanyl-diazepam anesthesia. The measurement of LCBF
was made using 50%–70% stable xenon with 20 min of inhalation interval and a shuttle method for computed tomography imaging.
All patients were anesthetized with 5.95±1.76 μg·kg−1 fentanyl and 0.22±0.07 mg·kg−1 diazepam under mechanical ventilation during CBF measurement. The values and distribution of LCBF on non-affected hemisphere
appeared to be unaltered by fentanyldiazepam anesthesia. We also assessed the cerebral carbon dioxide reactivity in 6 patients.
The cerebral carbon dioxide reactivity, expressed as percentage change in LCBF per unit change in arterial carbon dioxide
partial pressure, was 5.39±1.07, and there were no significant differences of reactivity among regions studied. In conclusion,
we showed reference values of LCBF and carbon dioxide reactivity, measured by stable xenon-enhanced computed tomography, in
patients under fentanyl-diazepam anesthesia. Carbon dioxide reactivity was preserved in all regions including gray matter,
white matter, and basal ganglia. 相似文献
53.
Atsushi Takai Yoshihiro Okabe Nobuhiro Aoki Mariko Takada Shuji Yamamoto Naoya Kimoto Mikio Fujita Akihiko Okada Chiharu Kawanami Yukinobu Takimoto Akio Orino 《Nihon Shokakibyo Gakkai zasshi》2007,104(10):1498-1503
A 77-year-old man, who underwent segmental pancreatectomy for intraductal papillary mucinous adenoma in 2001, was referred to our hospital with complaints of hematemesis and melena on January, 2004. Emergency upper gastrointestinal endoscopy showed a pulsating submucosal protrusion in the duodenal bulb, which was identified as a gastroduodenal arterial aneurysm measuring 1.5cm on abdominal CT imaging. Transcatheter arterial embolization of the aneurysm with metallic coils was successfully performed. Periodically repeated endoscopic examination has revealed the coils protruding into the duodenal lumen without any serious complication. 相似文献
54.
Takashi Ishimori Satoru Nakano Yasutane Mori Reiko Seo Taro Togami Tetsuya Masada Toshiaki Kusuhara Motoomi Ohkawa Seigo Nagao Yuichi Yamashita Satoshi Sugiura 《Magnetic resonance in medical sciences》2007,6(4):225-229
PURPOSE: We assessed the feasibility of utilizing three-dimensional (3D) phase sensitive inversion recovery (IR) images for preoperatively determining deep brain stimulator position. METHODS: We measured geometric distortion with a grid phantom and evaluated images of 3 volunteers to determine optimum imaging parameters for 3D phase sensitive IR. RESULTS: Geometric distortion measured less than 1.0%. Respective inversion and recovery times, which provided high T(1) contrast between the subthalamic nucleus and adjacent tissue, were 200 and 4000 ms. In studies of 3 volunteers and 2 patients, the subthalamic nucleus was clearly depicted in 3D phase sensitive IR images. The measured coordinates of the subthalamic nucleus agreed well with those calculated by conventional estimation from midpoint of the anterior and posterior commissure. CONCLUSION: Three-dimensional phase sensitive inversion recovery was useful in visualizing the subthalamic nucleus for effective deep brain stimulation. 相似文献
55.
Masato Nakajima Koji Tsuchiya Yoshihiro Honda Hiroshi Koshiyama Tatsuho Kobayashi 《General thoracic and cardiovascular surgery》2009,57(12):654-656
Although the causes of stroke are diverse, thromboembolism due to a mobile aortic thrombus is rare. We describe a surgical
case of acute massive pulmonary embolism after critical cerebral infarction associated with a mobile ascending aortic thrombus
in a 52-year-old woman. Concomitant surgical removal of the aortic thrombus and pulmonary embolectomy was performed successfully,
and the patient has been stable without recurrent thromboembolic complications after 18 months of follow-up. 相似文献
56.
K. Miyashita T. Sekita S. Minakuchi Y. Hirano K. Kobayashi & M. Nagao 《Journal of oral rehabilitation》1998,25(7):545-552
SUMMARY The purpose of this study was (1) to assemble and verify a system to measure the three‐dimensional (3‐D) movement of the upper and lower complete dentures and the movement of the mandible simultaneously, and (2) to analyse the relation between denture movements and the path of closure of the mandible during function. A 3‐D motion capture system with four infrared TV cameras was used for this purpose. The relation between the dentures and the mandibular movements was analysed through the change of the inner product of normal vectors of the denture occlusal planes and mandibular planes. The mandibular movements were classified into two types the normal stroke (the path of closure was on the ipsilateral side of mastication) and the reverse stroke (on the contralateral side). The results showed that the system could measure the denture mobility within a 0·3 mm error. The mobility of the upper dentures had a correlation to the path of closure of the mandible regardless of the working side or nonworking side, and the lower dentures had a tendency to move toward the working side. 相似文献
57.
Yuichi Ando Kenji Kikuchi Naoya Ichikawa Kazuhiko Meigata Yuji Nomura Kenshi Watanabe Yoshifumi Beck Hisakazu Degawa Shinji Tomikawa Takeshi Nagao Hisanori Chida 《Surgery today》1997,27(4):353-356
We herein report the case of a 53-year-old man with a nonspecific acute colonic ulcer whose liver function deteriorated after he had undergone hepatectomy. He was referred to our hospital for a hepatoma caused by hepatitis B virus and a right hemihepatectomy was performed. His liver function was poor after the operation, and minor complications such as pleural effusion and biliary fistula developed. A large amount of melena was seen 29 days after the hepatectomy and he developed hemorrhagic shock. Superior mesenteric arteriography revealed pooling of blood in both the hepatic flexure of the ascending colon and the cecum. An emergency right hemicolectomy was performed. There was a 5 x 1-mm ulcer 18 cm distal to the ileocecal valve. Numerous erosions were observed to be scattered throughout the colonic mucosa. The patient recovered slowly and was discharged 6 months after the hepatectomy. This is the first report of an acute colonic ulcer that could have been caused by liver dysfunction. 相似文献
58.
A case is reported of unexpected atrial fibrillation in response to tooth extraction under intravenous sedation in a 70-yr-old patient with thoracic aneurysm of the aorta. Atrial fibrillation developed after the additional injection of a 2% solution of lidocaine containing 1:200,000 epinephrine. After 20 min, the arrhythmia disappeared spontaneously. The arrhythmia was associated with insufficient analgesia for tooth extraction, epinephrine in the local anesthetic, decreased blood pressure, and the presence of cardiovascular disease. Even when a low concentration of epinephrine is employed, caution should be paid to development of unexpected cardiovascular reactions in elderly patients with severe cardiovascular disease. We conclude that an electrocardiogram, blood pressure device, and pulse oximeter should be used in high-risk patients in order to prevent and detect potentially dangerous cardiovascular emergencies, even if dental treatment is scheduled under local anesthesia. 相似文献
59.
60.
Seiitsu Ono Takashi Imai Shigeru Munakata Keiichi Takahashi Fumio Kanda Kazuki Hashimoto Takahiko Yamano Natsue Shimizu Koichi Nagao Mitsuo Yamauchi 《Journal of the neurological sciences》1998,160(2):565-147
During the last 10 years, we have demonstrated morphological and biochemical abnormalities of skin extracellular matrices in amyotrophic lateral sclerosis (ALS). However, currently little is known concerning collagen of the spinal cord in ALS. We measured the amount of collagen and characterized collagen at light and electron microscopic levels in posterior funiculus, posterior half of lateral funiculus and anterior horn of cervical enlargement of the spinal cord obtained from ten patients with ALS, 11 patients with other neurologic diseases (control group A), and ten patients without neurologic ones (control group B). In posterior half of lateral funiculus and anterior horn, (1) by light microscopy, there was no significant difference in vessel wall area between ALS patients and control groups A and B; (2) ultrastructurally, collagen bundles were more fragmented and widely separated, and the fibrils were randomly oriented in the perivascular space of capillaries in ALS patients, which were not observed in any areas of control groups or in posterior funiculus of ALS patients; and (3) the collagen contents in ALS were significantly lower (P<0.001 and P<0.001, respectively) than those in control groups A and B. Fragmented and widely separated collagen bundles in the interstitial tissue surrounding capillaries and markedly decreased amount of collagen in posterior half of lateral funiculus and in anterior horn of ALS could be related to the degeneration of the upper and lower motor neurons in the spinal cord in ALS, that is, selective neuronal vulnerability in ALS. 相似文献