全文获取类型
收费全文 | 9940篇 |
免费 | 406篇 |
国内免费 | 83篇 |
专业分类
耳鼻咽喉 | 113篇 |
儿科学 | 107篇 |
妇产科学 | 196篇 |
基础医学 | 1179篇 |
口腔科学 | 246篇 |
临床医学 | 603篇 |
内科学 | 2674篇 |
皮肤病学 | 237篇 |
神经病学 | 864篇 |
特种医学 | 531篇 |
外科学 | 1486篇 |
综合类 | 28篇 |
一般理论 | 1篇 |
预防医学 | 342篇 |
眼科学 | 140篇 |
药学 | 635篇 |
中国医学 | 24篇 |
肿瘤学 | 1023篇 |
出版年
2023年 | 49篇 |
2022年 | 122篇 |
2021年 | 205篇 |
2020年 | 107篇 |
2019年 | 149篇 |
2018年 | 187篇 |
2017年 | 134篇 |
2016年 | 171篇 |
2015年 | 165篇 |
2014年 | 288篇 |
2013年 | 306篇 |
2012年 | 458篇 |
2011年 | 500篇 |
2010年 | 352篇 |
2009年 | 282篇 |
2008年 | 465篇 |
2007年 | 564篇 |
2006年 | 535篇 |
2005年 | 553篇 |
2004年 | 545篇 |
2003年 | 580篇 |
2002年 | 555篇 |
2001年 | 291篇 |
2000年 | 265篇 |
1999年 | 264篇 |
1998年 | 147篇 |
1997年 | 124篇 |
1996年 | 119篇 |
1995年 | 84篇 |
1994年 | 81篇 |
1993年 | 61篇 |
1992年 | 176篇 |
1991年 | 135篇 |
1990年 | 142篇 |
1989年 | 149篇 |
1988年 | 119篇 |
1987年 | 118篇 |
1986年 | 114篇 |
1985年 | 97篇 |
1984年 | 63篇 |
1983年 | 52篇 |
1982年 | 31篇 |
1981年 | 31篇 |
1979年 | 75篇 |
1978年 | 42篇 |
1977年 | 37篇 |
1975年 | 30篇 |
1970年 | 30篇 |
1969年 | 35篇 |
1967年 | 30篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
Mitsuhiro Tozaki Kunihiko Fukuda Masafumi Suzuki 《Magnetic resonance in medical sciences》2006,5(3):137-146
PURPOSE: The purpose of this study was to assess the relationship between the amount of scirrhous component in invasive ductal carcinoma and its MR characteristics. MATERIALS AND METHODS: We retrospectively reviewed 71 consecutive patients with invasive ductal carcinoma smaller than 25 mm (average, 16.6 mm) in diameter. The scirrhous component was defined as invasive foci in small clusters of cancer cells showing desmoplasia. Invasive ductal carcinoma was subclassified into 3 groups in accordance with the amount of the scirrhous component (scirrhous component degree; SCD): SCD I (scirrhous component less than 20%), SCD II (intermediate), and SCD III (more than 80%). Dynamic magnetic resonance (MR) imaging was performed using volumetric interpolated sequence. Prior to dynamic study, T2*-weighted first-pass perfusion images were obtained before, during, and after bolus injection of 0.1 mmol Gd-DTPA/kg. RESULTS: Twenty-eight lesions were classified as SCD I, 14 as SCD II, and 29 as SCD III. Mass margin and signal intensity loss in the perfusion study were significantly different among the 3 SCD groups (P<0.001). The kinetic patterns were significantly different among the 3 SCD groups (P=0.04), and between SCD I/II and SCD III (P=0.03). The presence of enhancing internal septations was significantly different between SCD I/II and SCD III carcinomas (P=0.05). Central enhancement was only observed in SCD I carcinoma (4%; 3/71). CONCLUSION: The histological predominance of the scirrhous component in invasive ductal carcinoma may be one explanation for the differences in morphologic and kinetic patterns on MR imaging. 相似文献
6.
Takako Miyamae Masaaki Mori Yasuji Inamo Youichi Kohno Shuji Takei Motoharu Maeda Takuji Murata Shuji Nakata Hiroshi Kawai Yukiko Hirano Yukiji Date Katsuhiko Kitamura Shumpei Yokota 《Ryūmachi》2003,43(3):538-543
OBJECTIVES: To reveal the frequency and the clinical characteristics of dystrophic calcification that occurs in children with juvenile dermatomyositis, multi-center analysis was constructed. METHOD: Fifty children with JDM were enrolled, and 14 of them (28.0%) were complicated with calcinosis. Clinical symptoms and laboratory tests at onset, initial therapy and disease course were compared in children with and without calcinosis. RESULTS: The mean age of the onset of calcinosis was 4.78 +/- 3.33 years, and it was younger than those of children without calcinosis (8.66 +/- 3.85 years) (P = 0.0017). No differences of clinical manifestation except Gower's sign were observed. The frequency of positive anti-nuclear antibody was 7.1% in children with calcinosis and 52.9% without calcinosis (P = 0.0112). The initial therapy of methylprednisolon pulses gave no effects on prognosis of calcium deposition. The calcinosis appeared in 1.56 +/- 1.91 year after the onset of the disease. The various types of calcium deposition including large tumorous clumps, subcutaneous plaques or nodules, sheet-type calcification were deserved. They appeared over knee joints (64.3%), elbow joint (64.3%), and hip processes (50.0%). Calcinosis affecting the subcutaneous tissues frequently resulted in painful superficial ulceration of the overlying skin (42.9%), local infection (50.0%), and limitation of joint movement (14.3%). Although aluminum phosphate was effective in 2 children among 7, no other effective treatment was recommended. In 5 cases, surgical removal of tumorous clumps was operated. Thus, juvenile dermatomyositis is frequently complicated with calcinosis. This type of calcinosis was found to be unlikely to resolve completely, and resulted in severe disability in children. 相似文献
7.
Active production of anti-human T-lymphotropic virus type I (HTLV-I) IgM antibody in HTLV-I-associated myelopathy 总被引:2,自引:0,他引:2
Kunihiko Nagasato Tatsufumi Nakamura Ohishi Kiyosumi Kohji Shibayama Masakatsu Motomura Ichinose Katsuhiro Mitsuhiro Tsujihata Shigenobu Nagataki 《Journal of neuroimmunology》1991,32(2):105-109
We investigated the presence of anti-human T-lymphotropic virus type I (HTLV-I) IgM in sera and cerebrospinal fluid from patients with HTLV-I-associated myelopathy (HAM) by Western blot analysis. Analyses of 36 serum samples revealed that most patients (31/36; 86.1%) had anti-HTLV-I IgM, whereas only four of 23 (17.4%) HTLV-I carriers had it. In studies of cerebrospinal fluid, anti-HTLV-I IgM was detected in 24 of 36 (66.7%) HAM patients, whereas none was detected in nine HTLV-I carriers. The differences were statistically significant (p less than 0.01). These results suggest that persistent active replication of HTLV-I occurs in the central nervous system as well as in the peripheral blood of HAM patients, and may contribute to the development of HAM. 相似文献
8.
K Murata H Itoh G Todo T Itoh M Kanaoka M Furuta K Torizuka 《Investigative radiology》1986,21(1):24-30
This study was undertaken to clarify the microvascular anatomy of the normal human bronchial circulation, focusing on the bronchial venous system and its communication with the pulmonary circulation. Ten normal lungs obtained at autopsy were studied. Bronchial arteriography was performed in six lungs, pulmonary arteriography in two lungs, and pulmonary venography in another two. Using radiologic methods, including microradiography, and serial histologic sections, we found numerous bronchial venous plexuses around the airways and blood vessels into which the bronchial capillaries drained. Frequent communications of the venous plexuses with the pulmonary veins and neighboring alveolar capillaries were also demonstrated. The bronchial venous plexus and its close connection with the pulmonary circulation may be important in various pathologic conditions involving the interstitial space, such as interstitial pulmonary edema. 相似文献
9.
10.
Staging of esophageal carcinoma in vitro with 4.7-T MR imaging 总被引:4,自引:0,他引:4