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   12638篇
  免费   988篇
  国内免费   511篇
耳鼻咽喉   34篇
儿科学   169篇
妇产科学   104篇
基础医学   535篇
口腔科学   104篇
临床医学   1819篇
内科学   1166篇
皮肤病学   101篇
神经病学   646篇
特种医学   727篇
外国民族医学   3篇
外科学   995篇
综合类   2763篇
现状与发展   1篇
一般理论   3篇
预防医学   670篇
眼科学   372篇
药学   2018篇
  34篇
中国医学   859篇
肿瘤学   1014篇
  2024年   53篇
  2023年   249篇
  2022年   313篇
  2021年   467篇
  2020年   525篇
  2019年   390篇
  2018年   392篇
  2017年   405篇
  2016年   465篇
  2015年   500篇
  2014年   664篇
  2013年   1092篇
  2012年   696篇
  2011年   729篇
  2010年   703篇
  2009年   515篇
  2008年   511篇
  2007年   669篇
  2006年   622篇
  2005年   585篇
  2004年   502篇
  2003年   406篇
  2002年   365篇
  2001年   398篇
  2000年   329篇
  1999年   252篇
  1998年   223篇
  1997年   157篇
  1996年   112篇
  1995年   96篇
  1994年   95篇
  1993年   100篇
  1992年   90篇
  1991年   128篇
  1990年   72篇
  1989年   44篇
  1988年   37篇
  1987年   17篇
  1986年   30篇
  1985年   20篇
  1984年   29篇
  1983年   15篇
  1982年   11篇
  1981年   13篇
  1980年   17篇
  1979年   14篇
  1978年   7篇
  1977年   3篇
  1976年   4篇
  1974年   3篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Abstract. 15 adults, each providing 4 non-adjacent untreated periodontal pockets with a probing depth (PD) exceeding 6 mm. volunteered for a randomized, split-mouth, double-blind, clinical study evaluating subgingival irrigation with chlorhexidine (CHX) or tetracycline HCl (TTC). The study protocol included oral hygiene instructions followed by scaling and root planing. Experimental and immediately adjacent teeth did not receive instrumentation. The 4 deep periodontal pockets in each patient were assigned to be irrigated with 150 ml CHX (0.12%). TTC (10 or 50 mg/ml; TTC10, TTC50), or sterile saline (control) in a single episode. Post-irrigation mechanical plaque control was supported by 2× daily CHX rinses throughout the 12-week observation interval. Recordings of oral hygiene (PlI), gingival health (GI). bleeding on probing (BoP). probing depth (PD), clinical attachment level (CAL), and microbial morphotypes from subgingival paper point samples were performed pre-irrigation. and at 1, 2, 4, 6, 8, 10, and 12 weeks post-irrigation. Mean post-irrigation PlI was low, fluctuating between 0.0 and 0.4, without significant differences between experimental groups. Mean pre-irrigation GI approximated 1.4 and reached 0.8 at the exit of study without significant differences between experimental groups. All experimental sites exhibited BoP pre-irrigation. BoP was significantly reduced in TTC50 compared to TTC10, CHX and control sites from week 8 post-irrigation. PDs were reduced for the experimental groups with TTC50 exhibiting the strongest reduction. CALs remained unaltered from pre-irrigation for TTC10. CHX and control sites over the 12-week observation interval, whereas TTC50 sites consistently improved to significantly differ from all other groups at week 10 and 12 post-irrigation. The distribution of bacterial morphotypes was significantly altered towards one of periodontal health for all experimental groups with a profound effect for TTC50 sites. Our results suggest that subgingival irrigation with TTC solutions at high concentrations may have a rôle in the management of adult periodontitis.  相似文献   
102.
目的探讨微波热凝切割睑球粘连的治疗效果。方法随机抽取1995年1月~1997年12月我科应用微波治疗睑球粘连22例进行回顾性总结。结果22例轻、中、重度睑球粘连患者,经1~4次热凝切割,均痊愈。结论微波技术切割睑球粘连操作简便易行,是一种较为理想的治疗方法。  相似文献   
103.
超声导向肝组织微波固化的实验研究   总被引:2,自引:0,他引:2  
目的:探讨不同穿刺方案形成的肝组织微波凝固区的大小、形态,为临床治疗,特别是大肝癌的治疗,提供实践基础。方法:利用离体新鲜牛肝,比较UMC-I型微波仪单针、两针及多针组合所形成凝固区的大小、形态。结果:单针穿刺可形成3.0cm×4.0cm头宽尾窄的滴水状凝固区。两针组合,距离在2.5~3.0cm之间造成的完全凝固区最大。不同穿刺方案,可形成8cm以下不同直径的球形凝固区。结论:适当的穿刺方案可使8cm以下的球形区域完全凝固  相似文献   
104.
  • ? When Freud first advanced the death drive it was considered a highly controversial theoretical idea. However, with the passage of time it has been slowly gaining support in certain psychoanalytical quarters.
  • ? This paper aims to demonstrate the clinical usefulness of this theory in accordance with the Freudian and Kleinian model.
  • ? Although the case history to be discussed is a severe case of alcohol dependence which had, previously, been unresponsive to treatment, many other maladies, both mental and physical, can be better understood in the context of the death drive being the principal motivating factor.
  相似文献   
105.
ABSTRACT

In this reflective article we introduce Moving Space, a creative movement and art project supporting female Asylum Seekers as they move through the transient space of temporary accommodation. We explore how this cross-modal approach supports women to anchor experiences of displacement, loss and trauma through the use of embodied and visual creative process. Moreover, we argue that the transient nature of the therapeutic space brings into focus women’s resourcefulness and resilience despite the adversity and uncertainty they are experiencing.  相似文献   
106.
107.
Sperm penetration assay (SPA) scores obtained from cryobanked semen were correlated with therapeutic insemination (TI) fecundity in a group of established sperm donors, thereby evaluating the efficacy of the SPA in screening donors for sperm banking. While the SPA has been used to separate fertile from infertile males, we altered assay conditions to use frozen semen and to distinguish performance among fertile donors. Three frozen ejaculates from 11 pregnancy-proven donors were analysed. Of 905 TI cycles, 275 recipients achieved 95 pregnancies. There were no significant relationships between fecundity and donor semen, washed sperm parameters, sperm recoveries or recipient age. A significant relationship was revealed between mean SPA scores (range 8.7-66.6 penetrations/ovum) and donor fecundity (range 0.04-0.16, P < 0.03). Sperm concentration was varied in an effort to establish the most sensitive test condition. Using 0.25x10(6) motile spermatozoa/ml, a highly significant relationship was observed (P < 0.002). The four donors with the lowest SPA scores achieved the four lowest fecundities. It is concluded that a modified SPA can be used on frozen donor semen to estimate donor fertility potential. If applied routinely in donor semen banking, poor quality applicants could be excluded, thereby increasing pregnancy rates while decreasing donor screening costs.  相似文献   
108.
The purpose of this study was to assess the time of onset of action of acrivastine in suppressing the wheal response to histamine (10 mg/ml) and allergen (10000 and 100000 BU/ml) in the skin prick test. Ten subjects with a well-documented allergy to pollen received single doses of 8 mg of acrivastine and placebo according to a randomized, double-blind, placebo-controlled, crossover treatment design. Duplicate skin prick tests were performed 0, 15, 20, 25, 30, and 60 min after medication. The results demonstrated a statistically significant suppression of the wheal reactions 15–20 min after medication, depending on the reaction producers used. The sum of all three producers showed a statistically significant effect on the wheal reaction 15 min after medication. The upper 95% confidence limit for time lag from dosing of acrivastine until reduction from placebo level commences was 6.5 min. The study substantiates that orally administered acrivastine has a rapid onset of action in the skin of allergic subjects. The results indicate that allergen SPT is a more sensitive tool for studying antihistaminergic activity than histamine SPT.  相似文献   
109.
目的 探讨血管内栓塞治疗脑动静脉畸形(AVM)的临床效果和安全性.方法 应用血管内栓塞治疗脑AVMll例,栓塞剂为NBCA,栓塞后3例行手术切除,3例行γ-刀治疗.结果 1例完全栓塞,5例栓塞70%—90%,3例栓塞50%—70%,2例栓塞小于50%.生活、工作完全正常治愈5例,症状明显改善4例,症状无改善2例.结论 血管内栓塞治疗脑AVM的方法是相对安全的,可治愈部分脑AVM,对于大型、重要功能区的脑AVM,血管内栓塞联合手术或放疗可提高治愈率,降低致残率和死亡率.  相似文献   
110.
目的: 探讨肾母细胞瘤术前经动脉化疗栓塞的疗效机制。方法: 17例肾母细胞瘤患儿介入治疗后再行肿瘤切除,另 22例行单纯手术切除。对照分析2组肾母细胞瘤样本中细胞和间质的变化,采用原位细胞凋亡(TUNEL 法) 检测瘤细胞凋亡,并通过免疫组化法检测瘤细胞P53、Bcl-2 和Bax蛋白的表达。术后随访2年以上。结果: 介入组与单纯手术组的肿瘤坏死区域平均面积分别为60%、15 %(Uc = 2.84);肿瘤组织呈X3、X4退变者分别为58.8%(10/17)和4.55%(1/22)(2c= 11.4)、间质纤维组织增生程度中、重度变化者分别为64.7%(11/17)和18.2%(4/22)(Uc = 2.72)、淋巴细胞侵润者分别为70.6%(12/17)和18.2%(4/22)(2c=10.9),2组有显著差异(P<0.01);介入组肿瘤细胞分裂指数的中位数为0.2/10高倍视野,明显低于单纯手术组的1.4/10高倍视野(Uc = 54.50 ,P<0.01);94.9(37/39)的病例中均有不同数量的阳性凋亡细胞出现。介入组肿瘤细胞凋亡指数的中位数为25.9/10高倍视野,明显高于单纯手术组的12.8/10高倍视野(Uc = 117.00,P<0.05)。P53和Bcl-2蛋白表达与瘤细胞凋亡及分化程度均无相关性(P>0.05),但Bax 蛋白在介入组瘤细胞表达率(80.0%)明显高于单纯手术组(40.0%),差异显著(P<0.05)。介入组2年无瘤生存率为73.3%(11/15),单纯手术组为42.9%(6/14)。结论: 经动脉化疗栓塞治疗能够有效杀伤肿瘤细胞、抑制肿瘤生长,诱导由Bax蛋白介导的肿瘤细胞凋亡。  相似文献   
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