首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1110篇
  免费   30篇
  国内免费   15篇
耳鼻咽喉   5篇
儿科学   30篇
妇产科学   65篇
基础医学   78篇
口腔科学   223篇
临床医学   82篇
内科学   353篇
皮肤病学   4篇
神经病学   31篇
特种医学   20篇
外科学   95篇
综合类   48篇
预防医学   32篇
眼科学   23篇
药学   30篇
中国医学   1篇
肿瘤学   35篇
  2024年   1篇
  2023年   10篇
  2022年   7篇
  2021年   12篇
  2020年   14篇
  2019年   12篇
  2018年   19篇
  2017年   12篇
  2016年   7篇
  2015年   14篇
  2014年   21篇
  2013年   29篇
  2012年   51篇
  2011年   78篇
  2010年   42篇
  2009年   30篇
  2008年   68篇
  2007年   77篇
  2006年   86篇
  2005年   67篇
  2004年   88篇
  2003年   80篇
  2002年   67篇
  2001年   67篇
  2000年   36篇
  1999年   39篇
  1998年   22篇
  1997年   29篇
  1996年   14篇
  1995年   7篇
  1994年   6篇
  1993年   5篇
  1992年   4篇
  1991年   9篇
  1990年   3篇
  1989年   6篇
  1988年   4篇
  1987年   1篇
  1985年   2篇
  1984年   2篇
  1982年   1篇
  1979年   2篇
  1978年   2篇
  1976年   1篇
  1965年   1篇
排序方式: 共有1155条查询结果,搜索用时 406 毫秒
91.
OBJECTIVES: The aim was to demonstrate the equivalent efficacy of intranasal estradiol (Aerodiol Servier, Istanbul, Turkey) 300 mg/day relative to a standard oral estradiol therapy of 2 mg/day and to assess the therapeutic value of the potential benefits of Aerodiol. METHODS: Two hundred and one postmenopausal women with severe menopausal symptoms were recruited to the trial. Women received either intranasal Aerodiol 300 microg/day (one spray delivery of 150 microg per nostril) or an oral estradiol 2 mg for 24 weeks. Severity of symptoms were compared based on the Kupperman index (KI) at the end of 24 weeks. RESULTS: The KI score decreased markedly in both groups between W0 and W24. At W24, the two treatments were shown to be statistically equivalent (P<0.001). The incidence of adverse events was very similar in both groups; those related to treatment were of mild or moderate intensity in 95% of cases for the nasal group and 90% for the oral group. CONCLUSIONS: In conclusion, pulsed estrogen therapy using Aerodiol is safe, easily used and highly efficient in alleviating postmenopausal symptoms with a dose of 300 microg. The dose of 300 microg in one administration per day offers the optimal therapy whilst being easily adaptable to each patient's clinical response.  相似文献   
92.
Prior studies have suggested that intravenous diltiazem reduces the probability of spontaneous conversion of atrial fibrillation (AF) to sinus rhythm in the electrophysiology laboratory and in patients with postoperative AF. Whether diltiazem exerts the same effect in patients presenting to the emergency department (ED) with spontaneous AF is unclear. Fifty patients presenting to the ED with new-onset or paroxysmal AF and a rapid ventricular rate (>100 beats per minute) were randomly assigned to receive intravenous diltiazem or esmolol during the first 24 hours of presentation. Conversion to sinus rhythm occurred in 10 patients (42%) in the diltiazem group compared with 10 patients (39%) in the esmolol group (P = 1.0). Diltiazem does not decrease the likelihood of spontaneous conversion of AF to sinus rhythm in the ED setting.  相似文献   
93.
Rapid rhythms often arise in the pulmonary veins during atrial fibrillation (AF). The activation patterns within pulmonary veins during these rapid rhythms are not well described. In 39 patients with paroxysmal AF, ostial recordings were obtained during AF in 110 pulmonary veins with a decapolar distal ring catheter. Pulmonary vein tachycardia (PVT) was defined as a pulmonary vein (PV) rhythm that had a cycle length shorter than at the adjacent left atrium. During AF, PVT was recorded in 93% of PV's, usually in the form of intermittent bursts that had a mean duration of 1,325 +/- 647 ms and mean cycle length of 125 +/- 20 ms. The mean cycle length of continuous PVT's (141 +/- 25) was longer than the mean cycle length of intermittent bursts of PVT (P < 0.05). The intermittent PVT's were associated with a shorter left atrial cycle length than were the continuous PVT's. In 90% of PVTs, complex activation patterns attributable to simultaneous recordings from two or more overlapping fascicles were present at a segment of the pulmonary vein ostium, and the mean cycle length of these recordings was 80 +/- 32 ms. PVT during AF is much more often intermittent than continuous. The relationship between PVT cycle length and left atrial cycle length suggests that PVT's influence the left atrium during AF. PVT must be distinguished from recordings within PV's that have a short cycle length as a result of simultaneous recordings from two or more overlapping fascicles.  相似文献   
94.
Vitamin E stabilization successfully improved long‐term oxidation resistance of wear‐resistant ultra‐high‐molecular‐weight polyethylene (UHMWPE) used for joint implants. Stabilization can be achieved by blending an antioxidant into the UHMWPE resin powder before consolidation and irradiation. Balancing the wear resistance and vitamin E content in the blend is the current challenge with this approach, because vitamin E hinders crosslinking of UHMWPE during irradiation, which decreases wear resistance. The vitamin E concentration in the blend is generally limited to less than 0.3 wt%. Wear‐ and oxidation‐resistant UHMWPE has been obtained previously by consolidating blends of pre‐irradiated UHMWPE powders (XPE) into an unmodified polyethylene matrix (PE), where the improvement in wear rate depended on the radiation dose and fraction of XPE. We hypothesized that increasing the vitamin E content in the unirradiated matrix would not compromise wear and would further improve the oxidative stability of XPE/PE blends. Pin‐on‐disk wear testing showed that the XPE/PE blends containing 0.1–1.0 wt% vitamin E in the matrix had comparable wear rates. We used an aggressive accelerated aging test in the presence of the pro‐oxidant squalene and oxidation induction time (OIT) test and found that higher amounts of vitamin E resulted in stronger oxidation resistance for XPE/PE blends. The mechanical strength and toughness of the blends were not affected by changing the vitamin E content in the matrix. Stabilizing UHMWPE with higher vitamin E content may extend the service life of UHMWPE implants. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1860–1867, 2018.
  相似文献   
95.
目的在严格选择适应证的前提下,探讨成人牙周炎继发错牙合畸形患者正畸治疗的效果。方法分析19例成人牙周炎继发错牙合畸形患者的矫治过程,并对矫治效果进行评价。结果总成功率达到84.21%。结论在正确选择适应证、严格控制牙周状况、注意牙周炎矫治特点的情况下,成人牙周炎继发错牙合畸形的正畸治疗可以取得良好效果。  相似文献   
96.
Silver sulfadiazine 1%, mupirocin 2%, and fusidic acid 2% were compared to assess the antibacterial effect of a once-daily application on experimental rat 15% full-skin thickness burn wounds seeded 24 hours earlier with a 10 standard strain of methicillin-resistant staphylococci. The quantitative counts of seeded organism in burn eschar and subjacent muscle were determined at postburn day 7, beside the cultures of blood and lung biopsies. All tested topical agents were equally effective against methicillin-resistant in reducing local burn wound bacterial count and preventing systemic infection.  相似文献   
97.
Autonomic function is impaired in anemic patients with various etiologies such as vitamin B12 deficiency, sickle cell trait, and thalassemia major. However, there are insufficient data about autonomic functions in patients with iron deficiency anemia, the leading cause for anemia in the general population. In the present study we aimed to investigate the autonomic status in iron deficiency anemia by analyzing the heart rate variability (HRV). Age- and gender-matched 43 patients with iron deficiency anemia and 39 healthy subjects were undertaken into 24-hr Holter monitoring for assessing the HRV. We used serum levels of iron, iron binding capacity, C-reactive protein, vitamin B12, and folate to exclude other causes of anemia. While age, gender, vitamin B12 and folate levels were not different between the groups, HRV values were lower in patients with iron deficiency anemia compared to control group, which reflects parasympathetic withdrawal. Blood hemorheological factors such as decreased viscosity and/or altered red cell deformability may be responsible for this decreased parasympathetic activity. However, these components do not display remarkable contribution in iron deficiency anemia. Therefore, we speculated a probable link between anemia and the accentuated sympathetic activity that may be triggered by hypoxia sensed through carotid bodies. Despite lacking adequate convincing evidence concerning exact mechanism of carotid body activation, it is assumed as due either to hypoxia-related mitochondrial respiratory chain inhibition or potassium channel suppression that leads to intracellular calcium accumulation. In conclusion, the present study demonstrates an altered autonomic balance in patients with true iron deficiency anemia.  相似文献   
98.
99.
100.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号