全文获取类型
收费全文 | 30812篇 |
免费 | 3135篇 |
国内免费 | 98篇 |
专业分类
耳鼻咽喉 | 375篇 |
儿科学 | 1030篇 |
妇产科学 | 708篇 |
基础医学 | 4246篇 |
口腔科学 | 802篇 |
临床医学 | 3946篇 |
内科学 | 5980篇 |
皮肤病学 | 361篇 |
神经病学 | 2347篇 |
特种医学 | 1064篇 |
外国民族医学 | 1篇 |
外科学 | 4648篇 |
综合类 | 664篇 |
现状与发展 | 1篇 |
一般理论 | 27篇 |
预防医学 | 3003篇 |
眼科学 | 612篇 |
药学 | 2316篇 |
中国医学 | 134篇 |
肿瘤学 | 1780篇 |
出版年
2022年 | 216篇 |
2021年 | 491篇 |
2020年 | 278篇 |
2019年 | 418篇 |
2018年 | 571篇 |
2017年 | 412篇 |
2016年 | 446篇 |
2015年 | 468篇 |
2014年 | 798篇 |
2013年 | 1048篇 |
2012年 | 1618篇 |
2011年 | 1813篇 |
2010年 | 891篇 |
2009年 | 801篇 |
2008年 | 1443篇 |
2007年 | 1630篇 |
2006年 | 1467篇 |
2005年 | 1544篇 |
2004年 | 1347篇 |
2003年 | 1307篇 |
2002年 | 1225篇 |
2001年 | 876篇 |
2000年 | 858篇 |
1999年 | 842篇 |
1998年 | 375篇 |
1997年 | 349篇 |
1996年 | 334篇 |
1995年 | 294篇 |
1994年 | 271篇 |
1993年 | 244篇 |
1992年 | 613篇 |
1991年 | 566篇 |
1990年 | 537篇 |
1989年 | 502篇 |
1988年 | 500篇 |
1987年 | 482篇 |
1986年 | 460篇 |
1985年 | 497篇 |
1984年 | 387篇 |
1983年 | 333篇 |
1982年 | 251篇 |
1981年 | 261篇 |
1980年 | 211篇 |
1979年 | 335篇 |
1978年 | 275篇 |
1977年 | 246篇 |
1976年 | 212篇 |
1974年 | 239篇 |
1973年 | 241篇 |
1972年 | 214篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
Pretreatment of bone with osteoclasts affects phenotypic expression of osteoblast-like cells. 总被引:5,自引:0,他引:5
B D Boyan Z Schwartz C H Lohmann V L Sylvia D L Cochran D D Dean J E Puzas 《Journal of orthopaedic research》2003,21(4):638-647
Implant surface morphology regulates osteoblast phenotypic expression. Osteoblast sensitivity to non-biologic surfaces suggests that native bone surface features may also affect osteoblast response. To test this, MG63 osteoblast-like cells were grown for 7 days on bovine cortical bone wafers pretreated with rat bone marrow osteoclasts for 0, 10 or 20 days. Response to osteoclast-treated surfaces was compared to the response of MG63 cells to titanium surfaces with smooth and rough microtopographies. Cell number, differentiation (alkaline phosphatase activity and osteocalcin levels), and local factors (PGE(2) and TGF-beta1) were measured in confluent cultures. Compared to culture on plastic, cell number was reduced on all three types of bone wafers; this effect was dose-dependent with increasing resorption of the surface. Alkaline phosphatase specific activity was increased (P相似文献
73.
74.
75.
Effects of acetaminophen on adverse effects of influenza vaccination in health care workers. 总被引:1,自引:1,他引:0 下载免费PDF全文
F Y Aoki A Yassi M Cheang C Murdzak G W Hammond L H Sekl B Wright 《Canadian Medical Association journal》1993,149(10):1425-1430
OBJECTIVE: To evaluate the effects of acetaminophen on the incidence of adverse effects to, and the immunogenicity of, whole-virus influenza vaccine in health care workers. DESIGN: Prospective, randomized, double-blind placebo-controlled trial. SETTING: Health Sciences Centre, an acute care teaching hospital in Winnipeg. PARTICIPANTS: Of 474 hospital personnel who agreed to undergo influenza vaccination during the 1990-91 season 262 volunteered to participate in the study. INTERVENTIONS: A dose of 0.5 mL of inactivated trivalent whole-virus influenza vaccine was injected into the deltoid muscle. Volunteers were randomly assigned to ingest two capsules of acetaminophen in a half dose (162.5 mg per capsule) or a full dose (325 mg per capsule) or two identical placebo capsules. Capsules were to be taken at vaccination and at 4, 8 and 12 hours afterward. Subjects were asked to answer questions regarding six symptoms in a diary for the 3 days after vaccination and to record their ingestion of the study medication. MAIN OUTCOME MEASURES: Incidence of local (sore arm) and systemic (headache, fever, muscle ache, nausea and diarrhea) side effects as well as serum titres of hemagglutination inhibition (HAI) antibody to vaccine antigens before vaccination and 2 weeks and 6 months afterward. RESULTS: A total of 87, 87 and 88 subjects received the half dose, full dose and placebo respectively; 96% returned the diaries, 83% ingested all four doses of medication, and 87% volunteered all blood samples. Compared with the placebo group the incidence of sore arm was 25% to 28% lower in the half-dose and full-dose groups respectively at 24 hours after vaccination, and the rate of nausea was 90% lower in the full-dose group. The HAI titres were similar among the groups at the three test times. CONCLUSIONS: The full dose of acetaminophen significantly reduced the incidence of sore arm and nausea without affecting the antibody response. Acetaminophen use may increase the acceptance of influenza vaccine by health care workers in whom concern about side effects is an impediment to vaccination. 相似文献
76.
77.
A L Harris S Nicholson R Sainsbury C Wright J Farndon 《Journal of the National Cancer Institute. Monographs》1992,(11):181-187
Analysis of epidermal growth factor receptor (EGFr) and estrogen receptor (ER) was performed on tumor samples from 231 patients with operable breast cancer followed for up to 6 years after surgery. The median duration of follow-up in patients still alive at the time of analysis was 45 months. Thirty-five percent of patients (82) had tumors greater than 10 fmol/mg of 125I-EGF binding (EGFr+) and 47% (109) had cystolic ER concentration greater than 5 fmol/mg (ER+), with a marked inverse relationship between EGFr and ER (P less than .00001). EGFr was second only to axillary-node status as a prognostic marker for all patients in terms of both relapse-free and overall survival in univariate analysis (P less than .001, log-rank EGFr + v EGFr-). For patients with histologically negative axillary nodes, EGFr was superior to ER in predicting relapse and survival (P less than .01 and P less than .005, respectively, compared to P less than .1 and P less than .1, log-rank). In a multivariate (Cox model) analysis, only EGFr--out of EGFr, ER, size, and grade--was predictive for either relapse-free or overall survival for patients with node-negative disease (P = .052 and P = .026, respectively). One hundred eighty-seven case patients in the series were assessed for neu expression immunochemically, and 31 were positive. There was a highly significant increased risk of relapse and death in the positive group. In patients with otherwise good prognostic markers (ER+, node-negative, well-differentiated tumors), neu expression predicted for significantly worsened overall survival.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
78.
79.
Lateral orbitotomy--a review 总被引:2,自引:0,他引:2
Lateral orbitotomy is the standard surgical approach to lesions in the middle third of the orbit, to many lesions in the posterior third of the orbit and to benign lacrimal gland tumours. The indications, surgical technique and complications are discussed. 相似文献
80.