全文获取类型
收费全文 | 3724篇 |
免费 | 202篇 |
国内免费 | 33篇 |
专业分类
耳鼻咽喉 | 30篇 |
儿科学 | 52篇 |
妇产科学 | 52篇 |
基础医学 | 503篇 |
口腔科学 | 73篇 |
临床医学 | 281篇 |
内科学 | 920篇 |
皮肤病学 | 40篇 |
神经病学 | 240篇 |
特种医学 | 131篇 |
外科学 | 620篇 |
综合类 | 17篇 |
一般理论 | 1篇 |
预防医学 | 94篇 |
眼科学 | 114篇 |
药学 | 334篇 |
中国医学 | 3篇 |
肿瘤学 | 454篇 |
出版年
2023年 | 27篇 |
2022年 | 41篇 |
2021年 | 96篇 |
2020年 | 45篇 |
2019年 | 83篇 |
2018年 | 95篇 |
2017年 | 56篇 |
2016年 | 108篇 |
2015年 | 110篇 |
2014年 | 122篇 |
2013年 | 159篇 |
2012年 | 267篇 |
2011年 | 265篇 |
2010年 | 164篇 |
2009年 | 111篇 |
2008年 | 212篇 |
2007年 | 247篇 |
2006年 | 258篇 |
2005年 | 224篇 |
2004年 | 196篇 |
2003年 | 190篇 |
2002年 | 188篇 |
2001年 | 70篇 |
2000年 | 82篇 |
1999年 | 57篇 |
1998年 | 54篇 |
1997年 | 41篇 |
1996年 | 30篇 |
1995年 | 20篇 |
1994年 | 23篇 |
1993年 | 17篇 |
1992年 | 24篇 |
1991年 | 39篇 |
1990年 | 26篇 |
1989年 | 31篇 |
1988年 | 22篇 |
1987年 | 22篇 |
1986年 | 20篇 |
1985年 | 12篇 |
1984年 | 12篇 |
1983年 | 14篇 |
1982年 | 6篇 |
1979年 | 6篇 |
1977年 | 8篇 |
1975年 | 7篇 |
1974年 | 6篇 |
1971年 | 6篇 |
1970年 | 5篇 |
1968年 | 4篇 |
1966年 | 4篇 |
排序方式: 共有3959条查询结果,搜索用时 15 毫秒
1.
2.
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
3.
Shinya Yura Shintaro Terahata Noritaka Ohga Tomomi Yamashita 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,103(6):820-824
A 54-year-old man presented with an 8-year history of a hard asymptomatic mass of the left submandibular area. Total excision of the left submandibular gland with radical neck dissection was performed under a diagnosis of a submandibular tumor, probably a malignant mixed tumor. The pathologic diagnosis was carcinosarcoma consisting of carcinomatous and sarcomatous elements. The epithelial component was composed of squamous cell carcinoma, undifferentiated carcinoma, and adenocarcinoma. The nonepithelial component was composed of chondrosarcoma, osteosarcoma, spindle cell sarcoma, rhabdomyosarcoma, and liposarcoma. In the central area of the tumor, a few remnants of benign pleomorphic adenoma were identifiable. The finding suggested that in our patient, the carcinosarcoma arose from a preexisting pleomorphic adenoma. In view of the expected aggressive nature of the tumor, the patient was treated with postoperative radiotherapy of 60 Gy total, in 30 daily fractions of 2 Gy, and chemotherapy. He currently remains well and free of disease 24 months after treatment. 相似文献
4.
K Suzuki Y Ichinose K Hashimoto K Matsumoto T Suzuki K Imai H Yamanaka 《Hinyokika kiyo. Acta urologica Japonica》1990,36(5):557-560
Transrectal ultrasonotomography is useful in following patients with benign prostatic hypertrophy, because prostatic shape and weight are precisely assumed. We studied the effect of chlormadinone acetate (CMA) on benign prostatic hypertrophy. CMA (50 mg/day) was administered to 30 patients with benign prostatic hypertrophy. Weight reduction over 10% of the gland was noticed in 24 cases (80%). Mictional conditions were improved in 70% subjectively and in 71.4% objectively. However, the number of nocturia decreased in only 18.9%. Reduction rate of the weight was unrelated with the weight of prostate before administration of CMA. Duration of administration of CMA and the reduction rate were estimated. There was no definite difference in reduction rate for the first 15 months, but there was a slightly high reduction rate after administration of CMA for more than 24 months. In 3 cases, the shape and weight of prostate were studied after discontinuation of CMA. The size of prostate showed a tendency to increase gradually. 相似文献
5.
Satomi-Kobayashi Seimi Kawashima Seinosuke Sakoda Tsuyoshi Ueyama Tomomi Hirase Tetsuaki Kawai Miki Toh Ryuji Iwai Kenji Yokoyama Mitsuhiro 《Circulation journal》2004,68(3):247-253
BACKGROUND: Glycogen synthase kinase-3 beta (GSK-3beta) is involved in many cellular processes, such as metabolism, apoptosis, differentiation and proliferation. Insulin-like growth factor-1 (IGF-1), which is well known to have a hypertrophic effect on cardiomyocytes, inactivates (phosphorylates) GSK-3beta in some cell types. The role of GSK-3beta in cardiomyocytes as a negative regulator of cardiac hypertrophy has been recently reported and the present study investigated the role of GSK-3beta in the cardiac hypertrophy of cultivated neonatal rat cardiomyocytes induced by IGF-1. METHODS AND RESULTS: First, the IGF-1 induced signal transduction leading to GSK-3beta in neonatal rat cardiomyocytes was examined. The phosphatidylinositol (PI) 3-kinase/Akt/GSK-3 beta signaling induced by IGF-1 was investigated using inhibitors of PI 3-kinase and Ad AktAA, a dominant negative form of Akt. Furthermore, using Ad MEK DN, a dominant negative form of MEK, it was found that MEK negatively regulates Akt phosphorylation upon IGF-1 stimulation. Next, it was examined whether GSK-3beta acts as a negative regulator in the cardiac hypertrophy induced by IGF-1. Sustained stimulation by IGF-1 caused cardiac hypertrophy in protein synthesis and cellular morphology, and overexpression of unphosphorylatable GSK-3beta (Ad GSK-3beta S9A) repressed these hypertrophic effects of IGF-1. CONCLUSIONS: GSK-3beta may play an important role as a negative regulator of cardiac hypertrophy induced by IGF-1. 相似文献
6.
Hitoshi Matsuda Tomomi Hasegawa Takayo Maekawa Yutaka Okita 《Annals of thoracic and cardiovascular surgery》2005,11(2):132-134
A 23-year-old man was admitted for an aortic root aneurysm with mild aortic valve regurgitation (AR) and a small pressure gradient. At surgery, findings of aortic valve, one normal left posterior commissure and very rudimentary right anterior commissure, was compatible with the uni-commisural aortic valve. Aortic root replacement with valve-sparing technique was performed. Four years later no residual AR was observed. 相似文献
7.
Kunihiro Ichinose Mitsuru Nakamura Kenji Takezawa Ichiro Masutomi Yoichi Shima Yoko Hirayama Kahoko Sorimachi Teruhiko Shimizu Hiroyo Ishikawa Namiko Kaji Sayaka Nakajima Michiko Wataru Shiho Nishigaki Hiroshi Suwa Yosuke Toyama Masaki Okumura Yoshikazu Ishitsuka Ken Shimizu Kazuya Kokubo Kenji Sasaki Shodai Saito 《Seishin shinkeigaku zasshi》2006,108(9):945-954
8.
Yasuomi Ouchi Teiji Nakayama Toshihiko Kanno Etsuji Yoshikawa Tomomi Shinke Tatsuo Torizuka 《Journal of cerebral blood flow and metabolism》2007,27(4):803-810
Differentiation of impaired gait seen in idiopathic normal pressure hydrocephalus (iNPH) from parkinsonian gait is sometimes a great challenge and important for future medication in the clinical setting. To investigate dopaminergic contribution to its pathophysiology, two aspects of the trans-synaptic dopamine functions in the striatal region in eight iNPH patients na?ve to dopaminergic drugs were examined using positron emission tomography with a presynaptic marker [11C]CFT ([11C]2-beta-carbomethoxy-3beta-(4-fluorophenyl) tropane) that binds to dopamine transporter and a postsynaptic marker [11C]raclopride that binds to D2 receptor. Quantitative values of binding potentials (BPs) for [11C]CFT and [11C]raclopride were compared between patients and eight age-matched healthy subjects. The BPs and magnetic resonance imaging-based morphometric measures in iNPH were used for correlation analyses between the magnitude of binding of these in vivo markers and clinical severity of the patients. Analysis of variance showed significant reduction in [11C]raclopride binding in the putamen and nucleus accumbens (P<0.05, corrected for multiple comparison) and unchanged striatal [11C]CFT binding in iNPH. The dorsal putamen [11C]raclopride binding correlated negatively with gait severity (r=0.720, P<0.05), and the nucleus accumbens [11C]raclopride binding correlated positively with emotional recognition score (r=0.727, P<0.05) in the disease group. No significant relationship was observed between BPs and morphometric measures. The current result of the postsynaptic D2 receptor reduction along with preserved presynaptic activity in the nigrostriatal dopaminergic system reflects a pathophysiology of iNPH. Postsynaptic D2 receptor hypoactivity in the dorsal putamen may predict the severity of gait impairment in iNPH. 相似文献
9.
10.
Rats and guinea pigs were exposed continuously to 0.4 ppm NO2, 0.4 ppm O3 or a combination of the two gases for 2 weeks. The concentration of lipid peroxides in lungs of rats and guinea pigs exposed to NO2 alone or O3 alone did not change. The lipid peroxide level of rats inhaling the combined gases also did not change. However, the level of lipid peroxides in guinea pigs exposed to a combination of the two gases was increased to 2.2 times of the control level, showing a synergistic interaction. No increases of antioxidative protective enzyme activities and of antioxidants (such as NPSH, VE, VC) in guinea pigs exposed to NO2, O3 or the combined gases were found. In rats, no changes in enzyme activities and of the antioxidant contents were observed after NO2 alone, but O3 exposure produced slight increases of NPSH, VC, and GPx-H2O2. On the other hand, in rats exposed to the combined gases, marked synergistic increased of many antioxidative factors such as NPSH, VC, G6PD, GPx-cum.OOH and GPx-H2O2 were found. The results show that those animals which are able to increase antioxidative protective factors in the lung following exposure to the combined gases do not respond with a significant increase in lipid peroxides. On the other hand, in animals with poor induction-ability of these factors lipid peroxides are formed. This might explain why guinea pigs were the most sensitive to the effects of the combined gases. Furthermore, it was shown that in guinea pigs the increased level of lipid peroxides and that in rats the increased activities of antioxidative enzymes and the increased contents of the antioxidants were synergistic following exposure to the combined gases. 相似文献