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   10682篇
  免费   937篇
  国内免费   205篇
耳鼻咽喉   21篇
儿科学   425篇
妇产科学   85篇
基础医学   874篇
口腔科学   249篇
临床医学   816篇
内科学   1880篇
皮肤病学   93篇
神经病学   634篇
特种医学   146篇
外科学   435篇
综合类   886篇
现状与发展   1篇
预防医学   3624篇
眼科学   36篇
药学   731篇
  5篇
中国医学   317篇
肿瘤学   566篇
  2023年   225篇
  2022年   313篇
  2021年   984篇
  2020年   615篇
  2019年   507篇
  2018年   452篇
  2017年   398篇
  2016年   393篇
  2015年   448篇
  2014年   680篇
  2013年   911篇
  2012年   577篇
  2011年   572篇
  2010年   464篇
  2009年   446篇
  2008年   476篇
  2007年   444篇
  2006年   356篇
  2005年   297篇
  2004年   235篇
  2003年   234篇
  2002年   193篇
  2001年   138篇
  2000年   145篇
  1999年   119篇
  1998年   96篇
  1997年   101篇
  1996年   91篇
  1995年   77篇
  1994年   72篇
  1993年   65篇
  1992年   79篇
  1991年   61篇
  1990年   52篇
  1989年   48篇
  1988年   54篇
  1987年   45篇
  1986年   44篇
  1985年   47篇
  1984年   38篇
  1983年   33篇
  1982年   33篇
  1981年   32篇
  1980年   29篇
  1979年   18篇
  1978年   25篇
  1977年   13篇
  1976年   7篇
  1975年   7篇
  1974年   11篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
51.
BackgroundBrain iron deficiency (BID), especially for the substantia nigra (SN), without peripheral iron deficiency (ID) has been well documented as a ubiquitous finding for restless legs syndrome (RLS) patients. This close association suggests the biology of RLS BID can produce RLS symptoms. Association, however, cannot establish such a direct relationship. Instead, the BID of RLS could be experimentally produced to determine if it then produces significant RLS-like biological or behavioral features. Forward genetics approach led to identification from the BXD strains the BXD40 females (BXD40f) as a putative animal model for the RLS BID. The BXD40f on an iron-sufficient diet have a lower iron in the VMB (containing the SN) during the active but not inactive period. This was not found for the other BXD strains evaluated. The BXD40f on an ID diet uniquely have even greater reduced VMB but not peripheral iron, matching the RLS BID pathophysiology. A prior report found that the BXD40f on an iron-sufficient diet had an RLS-like behavior of increased activity occurring only in the last part of the active period that was not present in the other strains without the low VMB iron. This increased activity matches the circadian pattern of symptoms in RLS patients with increased urge or drive to move in the last part of the day. This study asks first: if you decrease the VMB iron by an iron deficient diet do the RLS-like behaviors worsen; and second will the dopaminergic treatments effective for RLS also reduce the worsened RLSlike behaviors.MethodsIn sum, 13 BXD40f mice post weaning were randomly assigned for 100 days to either a iron-sufficient diet (n = 6) or an ID diet (N = 7). They were then evaluated for 24-h activity in their home cage using implanted G2 EMitter telemetry device. At 3 h before the end of the active period IP doses were given every other day of either: saline (vehicle only), 12.5 mg levodopa, 25 mg levodopa, 0.5 mg quinpirole, or 1 0.0 mg quinpirole.ResultsThe ID compared to irons-sufficient diet produced earlier onset of the RLS-like behavior matching the earlier onset of symptoms with increasing severity of RLS. The dopaminergic treatments significantly reduced the RLS-like behavior. Added analyses of the RLS-like behaviors as decreased resting times showed similar results to activity increases.ConclusionsThese data demonstrate both that The BXD40f provide a useful animal model of RLS and also strongly support the hypothesis that the biology of RLS BID can produce RLS symptoms.  相似文献   
52.
推进“健康中国”行动要落脚在个人健康行动上,而发动自我健康行动的根本动力是责任,责任动力带动利益动力形成供需两端发力,并通过社会协同,以社区卫生服务为抓手,通过家庭医生签约服务对社区家庭健康负责,指导和管理家庭及个人健康行动,以点带面推动“健康中国”行动呈现全民健康行动的局面。  相似文献   
53.
54.
55.
Eating habits begin forming early in life when parental beliefs and behaviours often play a major role in shaping dietary intake. We aimed to assess maternal beliefs about the cost, social status, and nutritional value of foods in Samoa—a setting with an alarming burden of childhood obesity—and to determine how those beliefs may be related to child dietary intake. Samoan mothers (n = 44) sorted photographs of 26 foods commonly consumed in children in Samoa by cost, social status, and nutritional value (healthfulness). Responses were then assessed for their association with child dietary intake (reported using a food frequency questionnaire) using Pearson correlations. Mothers indicated that traditional Samoan foods were healthier, of higher social status, and lower cost compared with non‐traditional/imported food items. Compared with nutritional experts and a market survey of food prices, mothers demonstrated strong nutritional (r = .87, 95% CI [0.68, 0.95], p < .001) and consumer (r = .84, 95% CI [0.68, 0.93], p < .001) knowledge. The perceived cost of food was more strongly associated (r = ?.37, 95% CI [?0.66, 0.02], p = .06) with child dietary intake than either healthfulness or social status, with decreasing consumption reported with increasing food cost. Our findings contradicted the notion that the high social status of imported foods may be contributing to increased intake and rising prevalence of childhood obesity in this developing country setting. Despite their nutritional knowledge, Samoan mothers may need additional support in applying their knowledge/beliefs to provide a healthy child diet, including support for access to reasonably priced healthy foods.  相似文献   
56.
57.
58.
59.
60.
目的探究生酮饮食结合抗癫痫药物对难治性癫痫患者发作频率、血清单胺类神经递质的影响。方法将2016年1月至2018年2月我院神经内科收治的72例难治性癫痫患儿纳入研究,所有患儿均在原有抗癫痫药物基础上进行至少3个月的生酮饮食治疗,于治疗后3、6、12个月时统计癫痫发作频率,复查脑电图评价脑部放电控制情况;于治疗6个月时采用韦氏儿童智力量表对患儿治疗前后的认知功能进行评价,测定事件相关电位P300及血清去甲肾上腺素(NE)、多巴胺(DA)、5-羟色胺(5-HT)水平。结果所有患儿均接受随访,治疗维持3、6、12个月的患者分别为72例、60例、38例。生酮饮食治疗3、6、12个月时临床发作控制有效率分别为40.3%、50%、55.3%,完全控制发作率分别为2.8%、18.3%、21.1%;脑电波减少有效率分别为50%、68.3%、76.3%;与治疗前比较,治疗6个月时患儿言语智商、操作智商、全量表智商得分未见显著性改变(P 0.05);与治疗前比较,治疗6个月时患儿N_2PL显著降低,P3波幅及血清NE、DA、5-HT等神经递质水平显著升高(P 0.05)。结论总体上生酮饮食结合抗癫痫药物治疗难治性癫痫有效,不仅可降低癫痫发作次数,也可一定程度改善患儿认知功能,其机制可能与其对神经递质的调控相关。  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