全文获取类型
收费全文 | 5728篇 |
免费 | 308篇 |
国内免费 | 65篇 |
专业分类
耳鼻咽喉 | 52篇 |
儿科学 | 47篇 |
妇产科学 | 31篇 |
基础医学 | 574篇 |
口腔科学 | 72篇 |
临床医学 | 358篇 |
内科学 | 1717篇 |
皮肤病学 | 73篇 |
神经病学 | 392篇 |
特种医学 | 222篇 |
外科学 | 1007篇 |
综合类 | 12篇 |
一般理论 | 1篇 |
预防医学 | 115篇 |
眼科学 | 157篇 |
药学 | 354篇 |
中国医学 | 21篇 |
肿瘤学 | 896篇 |
出版年
2023年 | 44篇 |
2022年 | 66篇 |
2021年 | 147篇 |
2020年 | 79篇 |
2019年 | 132篇 |
2018年 | 153篇 |
2017年 | 139篇 |
2016年 | 148篇 |
2015年 | 152篇 |
2014年 | 204篇 |
2013年 | 203篇 |
2012年 | 406篇 |
2011年 | 434篇 |
2010年 | 287篇 |
2009年 | 205篇 |
2008年 | 363篇 |
2007年 | 351篇 |
2006年 | 368篇 |
2005年 | 379篇 |
2004年 | 325篇 |
2003年 | 337篇 |
2002年 | 371篇 |
2001年 | 79篇 |
2000年 | 80篇 |
1999年 | 80篇 |
1998年 | 87篇 |
1997年 | 57篇 |
1996年 | 54篇 |
1995年 | 57篇 |
1994年 | 41篇 |
1993年 | 39篇 |
1992年 | 34篇 |
1991年 | 19篇 |
1990年 | 24篇 |
1989年 | 25篇 |
1988年 | 24篇 |
1987年 | 9篇 |
1986年 | 15篇 |
1985年 | 10篇 |
1984年 | 10篇 |
1983年 | 11篇 |
1982年 | 6篇 |
1981年 | 11篇 |
1980年 | 11篇 |
1979年 | 4篇 |
1978年 | 3篇 |
1977年 | 5篇 |
1966年 | 2篇 |
1962年 | 1篇 |
1957年 | 1篇 |
排序方式: 共有6101条查询结果,搜索用时 33 毫秒
71.
72.
73.
Kohta Fujiwara Jun Hata Yuji Oshima Sawako Hashimoto Takeshi Yoshitomi 《Seminars in ophthalmology》2018,33(6):813-819
Purpose: To estimate the prevalence and risk factors for polypoidal choroidal vasculopathy (PCV) in a general Japanese population. Methods: This population-based, cross-sectional study was conducted in 2007 with subjects from the Hisayama Study. Of the 3,648 residents in Hisayama, Japan, 2,663 who were ≥ 50 years old were enrolled in this study. The characteristics of PCV were determined by fundus examination or based on indocyanine green and fluorescein angiographic findings. We evaluated the contributions of the risk factors for PCV. Results: Among the 207 participants with age-related macular degeneration (AMD), 174 (6.5%) had early AMD, and 33 (1.2%) had late AMD, including 10 participants with PCV (0.4%). Male and smoking habit were significant risk factors for the development of PCV. Conclusions: The prevalence of PCV is higher among Japanese subjects than Caucasians in Western countries. Male gender and smoking habit were significant risk factors for PCV in a general Japanese population. 相似文献
74.
Shota Hamada Shiro Hinotsu Katsuhito Hori Hiroshi Furuse Takehiro Oikawa Junichi Kawakami Seiichiro Ozono Hideyuki Akaza Koji Kawakami 《Supportive care in cancer》2012,20(4):813-820
Purpose
The objective of this study was to estimate the cost of antiemetic therapy for chemotherapy-induced nausea and vomiting (CINV) in daily practice in Japan. 相似文献75.
76.
77.
Hiyama T Tanaka S Yoshihara M Sasao S Kose K Shima H Tuncel H Ueno Y Ito M Kitadai Y Yasui W Haruma K Chayama K 《Journal of gastroenterology and hepatology》2004,19(7):756-760
BACKGROUND: Gastric cancer can progress through two pathways of genomic instability: chromosomal (CIN) and microsatellite instability (MSI). It is hypothesized that these two pathways are not always independent and that some tumors show overlap between these two mechanisms. METHODS: A total of 98 sporadic gastric cancers were classified based on their MSI status, using microsatellite assay with BAT26. Evidence for CIN was investigated by identifying loss of heterozygosity (LOH) events on chromosome arms, 5q, 10p, 17p, 17q, and 18q, which are regions harboring tumor suppressor genes that are significant in gastric cancer development. RESULTS: Twelve tumors (12%) showed high-frequency MSI (MSI-H). Overall, 43 of the tumors (44%) had at least one LOH event, with most frequent chromosomal losses observed on 10p and 18q (30%, respectively), followed by 5q (21%), 17p (14%), and 17q (12%). Interestingly, overlap was observed between CIN and MSI pathways. Of 43 cancers with LOH events, four (9%) were also MSI-H. It was also found that 48% of cancers without MSI-H had no LOH events identified, comprising a subgroup of tumors that were not representative of either of these two pathways of genomic instability. CONCLUSION: These results suggest that molecular mechanisms of genomic instability are not necessarily independent and may not be fully defined by either the MSI or CIN pathways in sporadic gastric cancers. 相似文献
78.
Togo S Nagano Y Masui H Tanaka K Miura Y Morioka D Endo I Sekido H Ike H Shimada H 《Hepato-gastroenterology》2005,52(63):913-919
BACKGROUND/AIMS: To determine an appropriate surgical treatment for patients with multiple liver metastases, we evaluated the efficacy of two-stage hepatectomy in patients with multiple bilobular liver metastases from colorectal carcinoma. METHODOLOGY: Some patients with multiple liver metastases are not candidates for a complete resection by a single hepatectomy, even when downstaged by chemotherapy, after portal embolization. In two-stage hepatectomy, the highest possible number of tumors is resected in a first, noncurative intervention, and the remaining tumors are resected after a period of liver regeneration. Two-stage hepatectomy was performed in 11 patients. RESULTS: Two-stage hepatectomy was feasible in all of the 11 patients. In 3 of them, the first stage was a major resection (more extensive than a lobectomy). This first hepatectomy was uneventful in all patients. The second hepatectomy was also uneventful in nine patients, but in one of the other two, a perihepatic fluid infection occurred, and in the other, postoperative liver failure developed due to a right subphrenic abscess. However, all patients were discharged. The percentage of the expected resection volume at one time, calculated from CT volumetry, was 75.5+/-1.2% and the prognostic score as surgical risk was 56.6+/-4.5. In two-stage hepatectomy cases, the percentage of the resected volume and the prognostic score in the first hepatectomy were 25.4+/-6.4% and 6.7+/-7.3, and in the second, 45.7+/-4.5% and 28.5+/-5.8. During the follow-up procedures, a residual hepatic recurrence was observed in 6 patients, and pulmonary recurrence in 9. The 1- and 3-year survival rates after the first hepatectomy were 90% and 45%, with median survivals of 18 months from the first hepatectomy. CONCLUSIONS: Two-stage hepatectomy is a surgical modality intended for patients with initial unresectable metastases. However, following such surgery, protective treatment against residual liver recurrence and lung metastasis will be a most important issue. 相似文献
79.
Takashi Tsukahara Masaru Tamura Hiromichi Yamazaki Hideyuki Kurihara Shigeru Matsuzaki 《Journal of cancer research and clinical oncology》1992,118(3):171-175
Summary The effects of -difluoromethylornithine (DFMO), radiation and the therapy of their combination were investigated in rats bearing G-XII glioma. DFMO treatment as well as radiation therapy prolonged the survival period when compared to the results in non-treated control rats. The combination therapy showed a greater effect on the survival rate than the single therapies, the effect being additive. The concentration of putrescine, spermidine, andN
1-acetylspermidine in tumor tissues was lowered by DFMO, while that of spermine was slightly elevated. Radiation decreased the concentration of all the polyamines, putrescine, spermidine, spermine andN
1-acetylspermidine. The concomitant treatment with DFMO and radiation further decreased the concentrations of putrescine andN
1-acetylspermidine in tumor tissues. The survival period of glioma-bearing rats is inversely correlated with the tissue levels of putrescine plusN
1-acetylspermidine.Abbreviations DFMO
-difluoromethylornithine
- BrdUrd
bromodeoxyuridine 相似文献
80.
Extremely early onset of ranitidine action on human histamine H2 receptors expressed in HEK293 cells
Fukushima Y Ishikawa T Saitoh T Tateishi K Ogihara T Fujishiro M Shojima N Honda M Kushiyama A Anai M Sakoda H Ono H Onishi Y Otsuka H Katagiri H Nagai R Omata M Asano T 《Digestion》2003,68(2-3):145-152
BACKGROUND/AIMS: Histamine H2 receptor antagonists are considered to exert their effects on gastric acid secretion more rapidly than proton pump antagonists. However, there are no reports concerning the direct interaction of a histamine H2 receptor antagonist with the human H2 receptor in terms of onset of action. This study aims to characterize how rapidly famotidine and ranitidine, the most widely used histamine H2 receptor antagonists, interact with the human histamine H2 receptor. METHODS: HEK293 cell lines, stably expressing human histamine H2 receptors, were obtained. The dose- and time-dependent effects of famotidine and ranitidine on [3H]-tiotidine binding and histamine-stimulated cAMP production were analyzed. RESULTS: Ranitidine inhibited both [3H]-tiotidine binding and histamine-stimulated cAMP production more promptly than did famotidine. Inhibition of histamine-stimulated cAMP production by Cmax doses of famotidine (20 mg p.o.) and ranitidine (150 mg p.o.) peaked by 15 and 2 min, respectively. [3H]-tiotidine binding was not saturated by 60 min at the famotidine Cmax, while the ranitidine Cmax had produced saturation by 15 min. CONCLUSION: Ranitidine inhibits the human histamine H2 receptor very rapidly. 相似文献