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   10439篇
  免费   886篇
  国内免费   89篇
耳鼻咽喉   5篇
儿科学   855篇
妇产科学   30篇
基础医学   1686篇
口腔科学   142篇
临床医学   369篇
内科学   824篇
皮肤病学   134篇
神经病学   358篇
特种医学   40篇
外科学   114篇
综合类   545篇
一般理论   1篇
预防医学   4993篇
眼科学   13篇
药学   937篇
  4篇
中国医学   252篇
肿瘤学   112篇
  2024年   21篇
  2023年   169篇
  2022年   733篇
  2021年   935篇
  2020年   477篇
  2019年   463篇
  2018年   418篇
  2017年   391篇
  2016年   390篇
  2015年   467篇
  2014年   595篇
  2013年   953篇
  2012年   505篇
  2011年   568篇
  2010年   407篇
  2009年   382篇
  2008年   403篇
  2007年   413篇
  2006年   284篇
  2005年   274篇
  2004年   256篇
  2003年   229篇
  2002年   202篇
  2001年   167篇
  2000年   126篇
  1999年   109篇
  1998年   110篇
  1997年   86篇
  1996年   90篇
  1995年   82篇
  1994年   79篇
  1993年   51篇
  1992年   68篇
  1991年   43篇
  1990年   47篇
  1989年   39篇
  1988年   50篇
  1987年   33篇
  1986年   30篇
  1985年   41篇
  1984年   31篇
  1983年   30篇
  1982年   31篇
  1981年   25篇
  1980年   18篇
  1979年   18篇
  1978年   25篇
  1977年   11篇
  1976年   16篇
  1975年   9篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
111.
IgE介导的食物过敏诊断程序及临床评价   总被引:12,自引:3,他引:9  
目的 对IgE介导的食物过敏的诊断流程进行临床评价。探讨高效的食物过敏诊断程序。方法 0~6岁患儿88例,以支气管哮喘、过敏性鼻炎、特应性皮炎以及消化道症状为主要临床表现,进行食物过敏原皮肤点刺试验(skin prick test,SPT),皮肤试验阳性者检测血清特异性IgE(sIgE)、sIgE阳性者进一步进行双盲安慰剂食物激发试验(double-blind placebo-control food challenge,DBPCFC)证实诊断。sIsE阴性者通过DBPCFC建立或排除诊断。结果 88例患儿中SPT(+)者25例。其中SPT(+)sIgE(+)者16例,SPT(+)sIsE(-)者9例;前者经DBPCFC进一步证实为食物过敏的有14例;后者通过DBPCFC建立诊断的3例。排除诊断的6例,根据SPT(+)sIgE(+)或SPT(+)sIsE(-)诊断食物过敏的阳性预计值为87.5%.阴性预计值为77.8%。结论 皮肤点刺试验结合sIgE检测有较高的食物过敏确诊率,当前两者不一致时,需要通过DBPCFC建立诊断。  相似文献   
112.
Nephropathy caused by diabetes mellitus (DM) is the main cause of end-stage renal disease (ESRD). To understand the association of dietary intake with renal function indicators among patients with diabetic nephropathy (DN), this cross-sectional study was conducted at the dietetic consultation clinic of the Taoyuan Armed Forces General Hospital in Taiwan. In total, 317 participants were recruited for this study. Patients with diabetes who had a urinary albumin–creatinine ratio (UACR) of ≥30 mg/g were defined as having DN. The anthropometric characteristics, blood biochemistry, and renal function of the participants were assessed. Furthermore, a semiquantitative food frequency questionnaire (SQFFQ) was administered to investigate the dietary intake of the participants in the DM and DN groups. The result showed that participants in the DN group were older, had longer diabetes duration and poorer glycemic control and renal function than those in the DM group. Logistic regression models revealed that intake of high-fat marine fishes had the lowest odds ratio (OR) for DN risk compared with other fishes (OR: 0.868; 95% CI: 0.781–0.965, p = 0.009). Shellfish, soybean products, and skim milk also provided better protective effects to decrease the risk of DN. A further analysis of polyunsaturated fatty acids revealed that Σn-3 PUFAs significantly reduced DN risk, while Σn-6 PUFAs did not, especially EPA (OR: 0.821; 95% CI: 0.688–0.979, p = 0.029) and DHA (OR: 0.903; 95% CI: 0.823–0.992, p = 0.033) regardless of whether the variables were adjusted, including diabetes duration, age, and HbA1c. Our findings suggest that a diet that incorporates high-fat fish, shellfish, soybean products, and a lower Σn-6/Σn-3 ratio can mitigate DN risk.  相似文献   
113.
Increased fruit and vegetable (FV) intake is associated with decreased risk of nutrition-related chronic diseases. Sociodemographic disparities in FV intake indicate the need for strategies that promote equitable access to FVs. The United States Department of Agriculture’s Gus Schumacher Nutrition Incentive Program (GusNIP) supports state and local programs that offer nutrition incentives (NIs) that subsidize purchase of FVs for people participating in the Supplemental Nutrition Assistance Program (SNAP). While a growing body of research indicates NIs are effective, the pathways through which GusNIP achieves its results have not been adequately described. We used an equity-focused, participatory process to develop a retrospective Theory of Change (TOC) to address this gap. We reviewed key program documents; conducted a targeted NI literature review; and engaged GusNIP partners, practitioners, and participants through interviews, workshops, and focus groups in TOC development. The resulting TOC describes how GusNIP achieves its long-term outcomes of increased participant FV purchases and intake and food security and community economic benefits. GusNIP provides NIs and promotes their use, helps local food retailers develop the capacity to sell FVs and accept NIs in accessible and welcoming venues, and supports local farmers to supply FVs to food retailers. The TOC is a framework for understanding how GusNIP works and a tool for improving and expanding the program.  相似文献   
114.
Background: Excessive mileage can be detrimental to bone mineral density among long-distance runners. The negative effects of mileage could be alleviated by appropriate nutrition. The purpose of this study was to analyse the dietary-lifestyle patterns in relation to bone mineral density and bone turnover markers among amateur marathoners. Methods: A total of 53 amateur male distance runners were divided into two clusters by k-means cluster analysis. Bone mineral density was measured by dual X-ray absorptiometry (DXA). Blood was drawn to analyse bone resorption marker C-terminal telopeptide (cTX) and bone formation marker amino-terminal propeptide of type I collagen (PINP). Food frequency intake and lifestyle information were measured by multicomponent questionnaire KomPAN®. Yearly average mileage per month was taken from each participant. Results: There were two distinguished clusters: Less-healthy-more-active-low-Z-score (LessHA) (n = 33) and More-healthy-less-active-high-Z-score (MoreHLA) (n = 20). LessHA had a lower frequency intake of pro-healthy food groups, a lower number of meals during a typical day, and a higher mileage training than the group of athletes who followed the MoreHLA. Athletes following the LessHA pattern also had a lower Z-score in the lumbar spine and femoral bone and a lower PINP. Conclusion: The current study suggests that pro-healthy dietary patterns and lower mileage may favour higher bone mineral density in male amateur marathoners.  相似文献   
115.
116.
Toxic ingredients in food can lead to serious food-related diseases. Such compounds are bacterial toxins (Shiga-toxin, listeriolysin, Botulinum toxin), mycotoxins (aflatoxin, ochratoxin, zearalenone, fumonisin), pesticides of different classes (organochlorine, organophosphate, synthetic pyrethroids), heavy metals, and natural antinutrients such as phytates, oxalates, and cyanide-generating glycosides. The generally regarded safe (GRAS) status and long history of lactic acid bacteria (LAB) as essential ingredients of fermented foods and probiotics make them a major biological tool against a great variety of food-related toxins. This state-of-the-art review aims to summarize and discuss the data revealing the involvement of LAB in the detoxification of foods from hazardous agents of microbial and chemical nature. It is focused on the specific properties that allow LAB to counteract toxins and destroy them, as well as on the mechanisms of microbial antagonism toward toxigenic producers. Toxins of microbial origin are either adsorbed or degraded, toxic chemicals are hydrolyzed and then used as a carbon source, while heavy metals are bound and accumulated. Based on these comprehensive data, the prospects for developing new combinations of probiotic starters for food detoxification are considered.  相似文献   
117.
Queensland is home to the largest diaspora of Māori and Pasifika peoples in Australia. They form an understudied population concerning experiences and challenges of food insecurity. This community co-designed research aims to explore the conceptualization of household food security by Māori and Pasifika peoples living in south-east Queensland. Participatory action research and talanoa were used to collect and analyse forty interviews with leaders representing 22 Māori and Pasifika cultural identities in south-east Queensland. Eight key themes emerged that conceptualise food security as an integral part of the culture and holistic health. These themes included: spirituality, identity, hospitality and reciprocity, stigma and shame, expectations and obligations, physical and mental health and barriers and solutions. Addressing food insecurity for collectivist cultures such as Māori and Pasifika peoples requires embracing food sovereignty approaches for improved food security through the co-design of practical solutions that impact social determinants and strengthen existing networks to produce and distribute affordable and nutritious food.  相似文献   
118.
儿童食物过敏发生率逐年增加,成为一个受到社会各界关注的重要健康问题。近期研究发现维生素D从胎儿时期即可影响人体免疫系统的调节作用,母体低水平的维生素D会增加子代过敏性疾病的风险。但目前国内外关于母体维生素D营养状态与子代食物过敏相关研究较少,为此本文就母体维生素D营养状态与子代食物过敏发生相关性进行综述。  相似文献   
119.
目的客观评价推拿治疗小儿泄泻伤食证的有效性。方法多中心、分层区组随机、平行对照临床研究方法。由3个中心协作完成小儿急性泄泻伤食证111例,包括观察组(推拿治疗)80例、对照组(培菲康和思密达治疗)31例。袪除脱落病例后,观察组76例、对照组30例。治疗2个疗程(6 d)后观察疗效。结果观察组疗效显著优于对照组(P<0.01)。2个疗程后,观察组主症总积分及分症(大便质地、质量)积分改善均优于对照组(P<0.01),而两组分症(大便次数、性状)积分改善差异无统计学意义。观察组总积分改善优于对照组(P<0.01)。结论推拿辨证疗法治疗小儿泄泻伤食证疗效优于西药(思密达+培菲康),值得推广应用。  相似文献   
120.
目的建立以红曲为原料的保健食品中总洛伐他汀含量测定的方法。方法用高效液相色谱法一次测定保健食品中两种结构形式洛伐他汀的总含量,色谱条件为:色谱柱(zorbaxC18,4.6×250mm,5μm);流动相:甲醇-水-磷酸(385:115:0.14);检测波长:238nm;流速:1.0mL/min。结果洛伐他汀在2.0~300μg/mL范围内线性关系良好,r=0.9999;平均回收率为99.5%,RSD为0.57%(n=9)。结论该高效液相色谱法简单、灵敏、快速、准确,适用于以红曲为原料的保健食品中总洛伐他汀的含量测定。  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