全文获取类型
收费全文 | 29057篇 |
免费 | 1359篇 |
国内免费 | 128篇 |
专业分类
耳鼻咽喉 | 312篇 |
儿科学 | 675篇 |
妇产科学 | 368篇 |
基础医学 | 3719篇 |
口腔科学 | 804篇 |
临床医学 | 1903篇 |
内科学 | 7687篇 |
皮肤病学 | 497篇 |
神经病学 | 2076篇 |
特种医学 | 958篇 |
外科学 | 5240篇 |
综合类 | 136篇 |
一般理论 | 3篇 |
预防医学 | 881篇 |
眼科学 | 339篇 |
药学 | 2079篇 |
中国医学 | 96篇 |
肿瘤学 | 2771篇 |
出版年
2023年 | 157篇 |
2022年 | 264篇 |
2021年 | 474篇 |
2020年 | 247篇 |
2019年 | 356篇 |
2018年 | 432篇 |
2017年 | 393篇 |
2016年 | 413篇 |
2015年 | 415篇 |
2014年 | 567篇 |
2013年 | 721篇 |
2012年 | 1140篇 |
2011年 | 1177篇 |
2010年 | 716篇 |
2009年 | 631篇 |
2008年 | 1173篇 |
2007年 | 1288篇 |
2006年 | 1283篇 |
2005年 | 1391篇 |
2004年 | 1315篇 |
2003年 | 1293篇 |
2002年 | 1222篇 |
2001年 | 1163篇 |
2000年 | 1257篇 |
1999年 | 1075篇 |
1998年 | 399篇 |
1997年 | 276篇 |
1996年 | 288篇 |
1995年 | 266篇 |
1994年 | 224篇 |
1993年 | 238篇 |
1992年 | 760篇 |
1991年 | 697篇 |
1990年 | 665篇 |
1989年 | 723篇 |
1988年 | 640篇 |
1987年 | 598篇 |
1986年 | 542篇 |
1985年 | 517篇 |
1984年 | 336篇 |
1983年 | 282篇 |
1979年 | 260篇 |
1978年 | 185篇 |
1977年 | 160篇 |
1974年 | 154篇 |
1973年 | 167篇 |
1972年 | 167篇 |
1971年 | 156篇 |
1970年 | 155篇 |
1969年 | 143篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
71.
C Kodama Y Mizoguchi N Kawada Y Sakagami S Seki K Kobayashi S Morisawa 《Osaka city medical journal》1989,35(1):1-11
When heat-killed Propionibacterium acnes, a gram-positive anaerobe, is intravenously injected into mice followed by an intravenous injection of gram-negative lipopolysaccharide (LPS) 7 days later, most of the mice die of massive hepatic cell necrosis within 24 hours of LPS injection. Using this experimental model, acute hepatic failure was induced in mice, and the tryptophan metabolism in the liver, brain and kidney was studied. As a result, the tryptophan level was remarkably high in all three organs, and the metabolism of both the tryptamine pathway and serotonin pathway was induced. However, in the brain, the tryptamine metabolism was more induced compared to the serotonin, suggesting that the metabolites of tryptamine, may be involved in hepatic encephalopathy. 相似文献
72.
73.
E Kakizoe Y Kobayashi K Shimoura K Hattori J Jidoi 《Journal of pharmacological and toxicological methods》1992,28(3):175-180
A reflectance spectrophotometric measurement was developed to analyze the microcirculation of the skin in real time. The relative absorption (RA) spectra were obtained from skin tissue 10 times per second using a spectro-multi-channel-photodetector system. In this system, white light was projected onto the skin of the back of the anesthetized rat and the spectrum of the reflected light between 450 and 643 nm was analyzed. Two absorption peaks at wavelengths of about 540 and 577 nm were observed, corresponding to the absorption peaks in the oxyhemoglobin (HbO2) spectrum. Either phlebotomy or the i.v. injection of norepinephrine (NE) reduced the RA spectrum. Peaks of the reduction in spectrum [(RA spectrum before the treatment) - (RA spectrum after the treatment)] were observed at about 540 and 577 nm. Injection of NE (0.75-48 ng/100 g B.W., i.v.) reduced the RA value at 577 nm dose-dependently, suggesting a decrease in the skin blood flow due to vasoconstriction. In addition, the content of HbO2 and capillary permeation were measured at the same time after the i.v. injection of Evans blue (EB) dye. As indices of HbO2 content and capillary permeation, RA changes at 540 and 610 nm (the latter is an absorption peak in the EB spectrum) were measured in real time, respectively. Both RA values increased dose-dependently after the intradermal injection of histamine (0.3-100 micrograms/site), suggesting the presence of vasodilation and an increase in permeability. The time at which the RA value for HbO2 reached a maximum was shorter than that for EB. These observations suggest that the method described here can detect changes in the HbO2 content and permeation of skin microcirculation at the same time, and in real time. 相似文献
74.
Patients on long-term hemodialysis (HD) are known to develop amyloid osteoarthropathy, evidenced as cystic radiolucencies on X-rays of the affected joints. To study the relationship between cystic radiolucencies and amyloid osteoarthropathy in 394 patients, we classified the severity of the cystic radiolucencies seen in the wrist joint on a 4-point scale and evaluated the association between lesion severity (grade) and several parameters. Biopsy was performed in 8 patients with 11 bone cysts of the wrist joint who had been operated for carpal tunnel syndrome. HD for 10 years or longer, age 50 or older and the presence of carpal tunnel syndrome were associated with severe cyst rating. There was no association between lesion grade and serum level of PTH-C, aluminum or beta 2-microglobulin (B2M). Ten of the 11 biopsied bone cysts in 8 patients with carpal tunnel syndrome demonstrated amyloid deposits which reacted with B2M. We conclude that a cystic radiolucency observed in the wrist joint of a patient undergoing HD indicates the deposition of amyloid. The cyst grade provides a useful marker for the severity of amyloid osteoarthropathy in HD patients. 相似文献
75.
Leiomyosarcoma originating in Meckel's diverticulum: Report of a case and a review of 59 cases in the English literature 总被引:1,自引:0,他引:1
Nobuyuki Shimizu Shu Kuramoto Toshiki Mimura Kaoru Kobayashi Masanori Kobayashi Shigeru Sakai Michio Kaminishi Takeshi Oohara 《Surgery today》1997,27(6):546-549
A 49-year-old woman was referred to our hospital with complaints of epigastric colicky pain and high fever. Abdominal computed
tomography and ultrasonography showed a solid tumor in the lower abdomen. Laparotomy revealed a neoplastic mass arising in
Meckel's diverticulum; therefore, a segment of the ileum, including the tumor-possessing diverticulum, was resected with a
lymph node dissection. A histologic examination confirmed the lesion to be leiomyosarcoma. In the English literature, 59 cases
of leiomyosarcoma in Meckel's diverticulum were reported from 1941 to 1994. The majority of patients were in their 4th decade
of life, with both sexes equally affected. The most frequent symptoms associated with this disease were abdominal pain with
nausea, vomiting, and melena. The majority were larger than egg-size. Although Meckel's diverticulum is difficult to diagnose
preoperatively, mesenteric arteriography may at times prove useful. The standard management of this particular tumor is wide
segmental resection, including the tumor and diverticulum with lymph node dissection. 相似文献
76.
77.
K Yamashita S Kobayashi H Fukuda H Koide K Okada T Tsunematsu 《Nihon Ronen Igakkai zasshi. Japanese journal of geriatrics》1991,28(4):546-550
The authors examined the relationship between cerebral white matter changes and mental function, blood pressure in 39 neurologically normal aged (21 males, 18 females, mean age 75.0 years) who had no latent lesions on MRI images. The severity of cerebral white matter changes was estimated by T1 value images on MRI and was measured in the bilateral frontal lobe on an axial slice at the level of the basal ganglia and in the bilateral anterior, middle, and posterior portions on axial slices at the level of the body of the lateral ventricle. Mental function was measured by the Hasegawa's dementia rating scale (HDS) and Kohs' block design test (Kohs' test). The severity of cerebral frontal white matter changes increased significantly with age (p less than 0.05). However there was no significant correlation between the severity of cerebral white matter changes and HDS, Kohs' test. The severity of frontal white matter changes correlated with the mean arterial blood pressure (p less than 0.02). These results suggest that the severity of cerebral white matter changes is not related with mental function in the normal elderly, and that the severity of frontal white matter lesions is related with mean arterial blood pressure. 相似文献
78.
Mariko Hosono H. Kobayashi Ryota Fujimoto Kazushige Tsutsui Yoshihiko Kotoura Tadao Tsuboyama Hikaru Hayashi Takashi Nakamura Junji Konishi 《Skeletal radiology》1997,26(9):525-528
Objective. To clarify the MRI features of parasymphyseal insufficiency fractures of the os pubis. Design and patients. MRI was performed in four postmenopausal women with parasymphyseal insufficiency fractures. The diagnosis was confirmed with
plain films in every patient. T1-weighted and T2-weighted images were obtained in four patients using a 1.5-T unit. Postcontrast
T1-weighted imaging was also done in three patients. Results and conclusions. MRI of pubic parasymphyseal insufficiency fracture characteristically demonstrates a hyperintense mass lesion with a hypointense
rim on T2-weighted imaging, showing peripheral and septal enhancement after contrast administration. It is important to have
this entity in mind in patients with osteoporosis, especially in patients with a history of pelvic irradiation for malignant
disease, so as not to misinterpret it as a chondroid tumor or bone metastasis. 相似文献
79.
In 195 elderly head-injured patients, Glasgow Coma Scale (GCS) scores (admission and 72 hours) and intracranial pressure (ICP) 0-12 days after injury were compared to 6 month Glasgow Outcome Scores. All patients remaining comatose at least 72 hours after injury died within 6 months. The mortality rate among patients with ICP greater than 20 mm Hg was higher both at 72 hours and at 6 months after injury. The 6 month mortality rate was 75% overall and 90% among patients with elevated ICP. This increased mortality in elderly patients with initially elevated ICP indicates that nurses and other health professionals should consider ICP as well as level of consciousness when counseling patients and families regarding the likely outcome after major head injuries. 相似文献
80.
Protein kinase C (PKC) activity was examined in the cytosolic and particulate fractions of homogenates obtained from 12 papillary thyroid carcinomas, 12 follicular thyroid adenomas, and the adjacent normal thyroid tissue. Particulate PKC activity was elevated significantly in thyroid carcinomas compared with normal thyroid tissue (P < 0.01) and adenomas (P < 0.05). By contrast, cytosolic PKC activity of carcinomas and adenomas was lower significantly than that of normal thyroid tissue (P < 0.01). The percentage of particulate PKC activity in carcinoma and adenoma was higher than in normal thyroid tissue (carcinoma, P < 0.001; adenoma, P < 0.01). The average particulate PKC activity of carcinomas more than 3 cm in diameter was significantly lower than that of carcinomas less than or equal to 3 cm in diameter (P < 0.05). The average cytosolic PKC activity of carcinomas more than 3 cm also was lower significantly than that of smaller carcinomas (P < 0.05). These results suggest that alterations in PKC activity may be important in the development of papillary thyroid cancer. 相似文献