全文获取类型
收费全文 | 15277篇 |
免费 | 1512篇 |
国内免费 | 177篇 |
专业分类
耳鼻咽喉 | 74篇 |
儿科学 | 479篇 |
妇产科学 | 197篇 |
基础医学 | 671篇 |
口腔科学 | 626篇 |
临床医学 | 1867篇 |
内科学 | 1833篇 |
皮肤病学 | 175篇 |
神经病学 | 512篇 |
特种医学 | 191篇 |
外科学 | 743篇 |
综合类 | 1372篇 |
现状与发展 | 1篇 |
一般理论 | 1篇 |
预防医学 | 6157篇 |
眼科学 | 214篇 |
药学 | 919篇 |
27篇 | |
中国医学 | 422篇 |
肿瘤学 | 485篇 |
出版年
2024年 | 38篇 |
2023年 | 281篇 |
2022年 | 884篇 |
2021年 | 1135篇 |
2020年 | 714篇 |
2019年 | 588篇 |
2018年 | 559篇 |
2017年 | 562篇 |
2016年 | 572篇 |
2015年 | 649篇 |
2014年 | 982篇 |
2013年 | 1367篇 |
2012年 | 864篇 |
2011年 | 861篇 |
2010年 | 711篇 |
2009年 | 688篇 |
2008年 | 695篇 |
2007年 | 663篇 |
2006年 | 592篇 |
2005年 | 488篇 |
2004年 | 381篇 |
2003年 | 322篇 |
2002年 | 274篇 |
2001年 | 255篇 |
2000年 | 177篇 |
1999年 | 151篇 |
1998年 | 160篇 |
1997年 | 182篇 |
1996年 | 128篇 |
1995年 | 111篇 |
1994年 | 116篇 |
1993年 | 115篇 |
1992年 | 94篇 |
1991年 | 78篇 |
1990年 | 67篇 |
1989年 | 62篇 |
1988年 | 79篇 |
1987年 | 39篇 |
1986年 | 35篇 |
1985年 | 54篇 |
1984年 | 33篇 |
1983年 | 21篇 |
1982年 | 29篇 |
1981年 | 25篇 |
1980年 | 14篇 |
1979年 | 15篇 |
1978年 | 14篇 |
1977年 | 9篇 |
1976年 | 6篇 |
1968年 | 5篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
Frances A. Tylavsky Luhang Han Lauren M. Sims Taylor W. Alex Mason Kecia N. Carroll Nicole R. Bush Kaja Z. LeWinn Melissa M. Melough Terryl J. Hartman Qi Zhao 《Nutrients》2022,14(11)
The objective of this study was to calculate an oxidative balance score (OBS) utilizing diet and lifestyle information collected from 1322 women during the second trimester of pregnancy in the Conditions Affecting Neurocognitive Development and Learning in Early Childhood study. An energy-adjusted OBS was calculated using nutrient information from a Food Frequency Questionnaire (FFQ), lifestyle measures, and plasma folate and vitamin D levels. Using the least absolute shrinkage and selection operator method, 91 food items from the FFQ were selected and they accounted for 82% of the variance in the OBS, with cruciferous vegetables, citrus fruits, fruit juice, and coffee being among the highest anti-oxidant predictors, and red meats and alcohol among the highest pro-oxidant contributors. Urinary F2-isoprostane, an objective indicator of oxidative stress, was lower with increasing OBS quintiles in a stairstep manner (p for trend = 0.0003), suggesting the possible utility of the OBS as an indicator of oxidative stress. The OBS was moderately correlated with the Healthy Eating Index (correlation coefficient = 0.6076), suggesting it provides a distinct measure of a healthy diet. In conclusion, the OBS may serve as a valid reflective indicator of urinary F2-isoprostanes and an epidemiological tool to inform intervention studies, in order to minimize oxidative stress during pregnancy. 相似文献
62.
Hanzhi Yu Runming Du Minmin Wang Fengyun Yu Juntao Yang Lirui Jiao Zhuoran Wang Haitao Liu Peixin Wu Till Brnighausen Lan Xue Chen Wang Shannon McMahon Pascal Geldsetzer Simiao Chen 《JMIR Public Health and Surveillance》2022,8(6)
BackgroundCOVID-19 vaccines are in short supply worldwide. China was among the first countries to pledge supplies of the COVID-19 vaccine as a global public product, and to date, the country has provided more than 600 million vaccines to more than 200 countries and regions with low COVID-19 vaccination rates. Understanding the public’s attitude in China toward the global distribution of COVID-19 vaccines could inform global and national decisions, policies, and debates.ObjectiveThe aim of this study was to determine the attitudes of adults living in China regarding the global allocation of COVID-19 vaccines developed in China and how these attitudes vary across provinces and by sociodemographic characteristics.MethodsWe conducted a cross-sectional online survey among adults registered with the survey company KuRunData. The survey asked participants 31 questions about their attitudes regarding the global allocation of COVID-19 vaccines developed in China. We disaggregated responses by province and sociodemographic characteristics. All analyses used survey sampling weights.ResultsA total of 10,000 participants completed the questionnaire. Participants generally favored providing COVID-19 vaccines to foreign countries before fulfilling domestic needs (75.6%, 95% CI 74.6%-76.5%). Women (3778/4921, 76.8%; odds ratio 1.18, 95% CI 1.07-1.32; P=.002) and those living in rural areas (3123/4065, 76.8%; odds ratio 1.13, 95% CI 1.01-1.27; P=.03) were especially likely to hold this opinion. Most respondents preferred providing financial support through international platforms rather than directly offering support to individual countries (72.1%, 95% CI 71%-73.1%), while for vaccine products they preferred direct provision to relevant countries instead of via a delivery platform such as COVAX (77.3%, 95% CI 76.3%-78.2%).ConclusionsAmong our survey sample, we found that adults are generally supportive of the international distribution of COVID-19 vaccines, which may encourage policy makers to support and implement the distribution of COVID-19 vaccines developed in China worldwide. Conducting similar surveys in other countries could help align policy makers’ actions on COVID-19 vaccine distribution with the preferences of their constituencies. 相似文献
63.
Utano Nakamura Taichi Nohmi Riho Sagane Jun Hai Kento Ohbayashi Maiko Miyazaki Atsushi Yamatsu Mujo Kim Yusaku Iwasaki 《Nutrients》2022,14(12)
Gamma-aminobutyric acid (GABA) is present in the mammalian brain as the main inhibitory neurotransmitter and in foods. It is widely used as a supplement that regulates brain function through stress-reducing and sleep-enhancing effects. However, its underlying mechanisms remain poorly understood, as it is reportedly unable to cross the blood–brain barrier. Here, we explored whether a single peroral administration of GABA affects feeding behavior as an evaluation of brain function and the involvement of vagal afferent nerves. Peroral GABA at 20 and 200 mg/kg immediately before refeeding suppressed short-term food intake without aversive behaviors in mice. However, GABA administration 30 min before refeeding demonstrated no effects. A rise in circulating GABA concentrations by the peroral administration of 200 mg/kg GABA was similar to that by the intraperitoneal injection of 20 mg/kg GABA, which did not alter feeding. The feeding suppression by peroral GABA was blunted by the denervation of vagal afferents. Unexpectedly, peroral GABA alone did not alter vagal afferent activities histologically. The coadministration of a liquid diet and GABA potentiated the postprandial activation of vagal afferents, thereby enhancing postprandial satiation. In conclusion, dietary GABA activates vagal afferents in collaboration with meals or meal-evoked factors and regulates brain function including feeding behavior. 相似文献
64.
Dongdong Lu Yu Pi Hao Ye Yujun Wu Yu Bai Shuai Lian Dandan Han Dongjiao Ni Xinhua Zou Jinbiao Zhao Shuai Zhang Bas Kemp Nicoline Soede Junjun Wang 《Nutrients》2022,14(12)
Constipation is a common problem in sows and women during late pregnancy. Dietary fiber has potential in the regulation of intestinal microbiota, thereby promoting intestinal motility and reducing constipation. However, the effects of fibers with different physicochemical properties on intestinal microbe and constipation during late pregnancy have not been fully explored. In this study, a total of 80 sows were randomly allocated to control and one of three dietary fiber treatments from day 85 of gestation to delivery: LIG (lignocellulose), PRS (resistant starch), and KON (konjaku flour). Results showed that the defecation frequency and fecal consistency scores were highest in PRS. PRS and KON significantly increased the level of gut motility regulatory factors, 5-hydroxytryptamine (5-HT), motilin (MTL), and acetylcholinesterase (AChE) in serum. Moreover, PRS and KON promoted the IL-10 level and reduced the TNF-α level in serum. Furthermore, maternal PRS and KON supplementation significantly reduced the number of stillborn piglets. Microbial sequencing analysis showed that PRS and KON increased short-chain fatty acids (SCFAs)-producing genera Bacteroides and Parabacteroides and decreased the abundance of endotoxin-producing bacteria Desulfovibrio and Oscillibacter in feces. Moreover, the relative abundance of Turicibacter and the fecal butyrate concentration in PRS were the highest. Correlation analysis further revealed that the defecation frequency and serum 5-HT were positively correlated with Turicibacter and butyrate. In conclusion, PRS is the best fiber source for promoting gut motility, which was associated with increased levels of 5-HT under specific bacteria Turicibacter and butyrate stimulation, thereby relieving constipation. Our findings provide a reference for dietary fiber selection to improve intestinal motility in late pregnant mothers. 相似文献
65.
Agustina Heredia-Martinez Guillermo Rosa-Diez Jorge R. Ferraris Anna-Karin Sohlenius-Sternbeck Carina Nihlen Annika Olsson Jon O. Lundberg Eddie Weitzberg Mattias Carlstrm Rafael T. Krmar 《Nutrients》2022,14(12)
Nitric oxide (NO) contributes to maintaining normal cardiovascular and renal function. This bioactive signalling molecule is generally formed enzymatically by NO synthase in the vascular endothelium. NO bioactivity can also be attributed to dietary intake of inorganic nitrate, which is abundant in our diet, especially in green leafy vegetables and beets. Ingested nitrate is reduced to nitrite by oral commensal bacteria and further to NO systemically. Previous studies have shown that dialysis, by means of removing nitrate and nitrite from the body, can reduce NO bioactivity. Hence, dietary intervention approaches aimed to boost the nitrate–nitrite–NO pathway may be of benefit in dialysis patients. The purpose of this study was to examine the kinetics of plasma nitrate and nitrite after a single intake of nitrate-rich concentrated beetroot juice (BJ) in adult hemodialysis (HD) patients and in age-matched healthy volunteers (HV). Eight HD patients and seven HV participated in this single center, randomized, single-blind, placebo-controlled, crossover study. Each participant received a sequential single administration of active BJ (70 mL, 400 mg nitrate) and placebo BJ (70 mL, 0 mg nitrate) in a random order separated by a washout period of seven days. For the kinetic analysis, blood samples were collected at different time-points before and up to 44 h after BJ intake. Compared with placebo, active BJ significantly increased plasma nitrate and nitrite levels both in HD patients and HV. The area under the curve and the maximal concentration of plasma nitrate, but not of nitrite, were significantly higher in HD patients as compared with HV. In both groups, active BJ ingestion did not affect blood pressure or plasma potassium levels. Both BJs were well tolerated in all participants with no adverse events reported. Our data provide useful information in planning dietary nitrate supplementation efficacy studies in patients with reduced NO bioactivity. 相似文献
66.
Jing Ying Lim Roslee Rajikan Noh Amit Nazlena Mohamad Ali Haslina Abdul Hamid Huey Yin Leong Maslina Mohamad Bi Qi Koh Aini Musa 《Nutrients》2022,14(12)
Dietary intervention is generally accepted as the mainstay of treatment for patients with disorders of amino acid metabolism (AAMDs). However, dietary adherence to a low-protein diet is always reported as a common challenge among these patients. This study explored the perception of barriers and motivators to dietary adherence among caregivers of AAMD patients in Malaysia. Twenty caregivers of children with AAMDs receiving ongoing treatment at the genetic clinic participated in an online focus group discussion from November to December 2021. Findings showed a total of five interrelated main themes identified from focus group discussion (FGD) exploring parents’ experiences related to the management of their child’s daily diet. The barriers to dietary adherence were burden of dietary treatment, diet and dietary behavior, parenting challenges, limited knowledge related to dietary treatment, and challenges in healthcare system delivery. Key factors facilitating good dietary adherence include good knowledge of dietary treatment, parental coping strategies, social coping, and dietary behavior. In conclusion, despite the existence of several barriers to the implementation of dietary treatment, caregivers managed to use a wide range of coping strategies to overcome some, if not all, of the challenges. The important next step is to develop, in conjunction with multidisciplinary healthcare professionals, feasible implementation strategies that could address these barriers and at the same time improve the quality of life of caregivers. 相似文献
67.
Xuan Wang Tiantian Li Hongrui Li Dajun Li Xianyun Wang Ai Zhao Wannian Liang Rong Xiao Yuandi Xi 《Nutrients》2022,14(12)
Inflammation is known as an important mechanism of cognitive dysfunction. Systemic immune inflammation index (SII) and system inflammation response index (SIRI) are two blood inflammatory markers, which are related to many chronic diseases including cognitive impairment. It is recognized that dietary inflammatory index (DII), which is used to estimate the overall inflammatory potential of diet, may be related to mild cognitive impairment (MCI) as well. This study aimed to explore the relationship between SII, SIRI and DII, as well as the role of these inflammatory indexes on MCI in elderly people. A total of 1050 participants from Beijing were included. Neuropsychological tests were used for cognitive evaluation. Energy-adjusted DII scores were calculated based on semi-quantitative food frequency questionnaire. Blood samples were tested for calculating SII and SIRI. Log-binomial regression models were used to estimate the correlation of indexes. After adjusting demographic characteristics, SII and SIRI in MCI individuals were higher than controls (p ≤ 0.001). DII, SII and SIRI had positive relationship with MoCA scores (p < 0.005). DII also correlated with SIRI in MCI (β = 0.11, p = 0.031). Higher DII and SIRI could definitely increase the risk of MCI, as well as DII and SII (p < 0.005). In conclusion, DII was positively correlated with blood inflammation. The elderly with higher level of DII and SIRI, or DII and SII could be considered as people with higher risk of developing MCI. 相似文献
68.
Nicole Fakhoury Sayegh Gessica N. H. A. Heraoui Hassan Younes Lea Nicole Sayegh Christa Boulos Raymond Sayegh 《Nutrients》2022,14(12)
Non-alcoholic fatty liver disease (NAFLD) is considered the most common liver injury worldwide. NAFLD can evolve into non-alcoholic steatohepatitis (NASH) with or without fibrosis. The objectives of this study were to determine the nutritional profile and dietary patterns of NAFLD Lebanese patients and to report the type of diet-related to the presence of hepatic fibrosis. We hypothesized that the traditional pattern was related to a low risk of fibrosis. This cross-sectional study included 320 eligible Lebanese NAFLD patients. Three dietary patterns were identified: the Traditional diet, the High Fruit diet, and the Westernized diet. Multivariate analysis showed a significant relationship between high adherence to the traditional diet and absence of hepatic fibrosis with a decreased risk of 82%, p = 0.031 after adjusting for its covariables. Fruits were absent from this dietary pattern. Although our results pointed to a possible relationship between fibrosis in NAFLD patients and fruit intake, experimental studies are needed to show whether this is a causal relationship. However, the results obtained in this study may contribute to the planning of dietary interventions and recommendations and enable a better follow-up for NAFLD patients with fibrosis. 相似文献
69.
Je-Young Park Jeng-Feng Chen Hosung Choi Wilson W.S. Ho Ni Nyoman Indra Lesthari Joyce Teng Ee Lim Ting Song Lim Stephen Lowe Beverly Ong-Amoranto Vasanop Vachiramon Rungsima Wanitphakdeedecha Martina Kerscher 《The Journal of clinical and aesthetic dermatology》2022,15(6):10
ObjectiveWe sought to examine the current skin quality trends and gaps in clinical practice in the Asia Pacific region and develop a practical guide to improve skin quality.MethodsMedical practitioners from 11 countries in the Asia Pacific region completed an online survey on current trends in skin quality treatment. A panel of 12 leading experts convened for a virtual meeting to develop a practical guide for skin quality improvement.ResultsA total of 153 practitioners completed the survey. The four most common skin quality issues were uneven skin tone, skin surface unevenness, skin laxity, and sebaceous gland hyperactivity and enlarged pores. Most practitioners reported using a combination of treatment modalities for each skin quality issue. It was also observed that each treatment modality could be used to treat several skin quality issues. A multimodal approach targeting different interrelated issues across the tissue planes was recommended for balanced results. The panel developed a practical guide for the appropriate combinations and sequence of treatments, and created treatment protocols for specific skin quality outcome goals. The guide employed an “inside-out” approach, treating the deeper tissue planes prior to the superficial layers to achieve harmonious results.LimitationsFuture studies are needed to support the recommended treatment protocols for skin quality improvement.ConclusionThese findings provide valuable insights on current skin quality trends and gaps in clinical practice. The practical guide provides a framework for practitioners to customize their treatment plan according to each patient’s needs. 相似文献
70.
目的了解潍坊市1—6岁儿童厌食症形成的原因,为制定儿童饮食行为干预措施提供科学依据。方法选取2009年12月至2013年12月期间在潍坊市益都中心医院及青州市中医院就诊的1—6岁厌食症儿童,对其抚养人进行喂养情况的问卷调查,并对问卷结果进行分析。结果断乳时间过晚、过多零食、强迫进食、贪玩为儿童厌食症发病关系密切的高危因素(OR值分别为1.446、1.328、1.422和1.369,均P〈0.05)。结论防治厌食症应注意优化家庭养育环境,按时断乳,平衡日常饮食,养成良好饮食习惯,并针对儿童喂养做好宣传教育,指导家长科学喂养,以促进儿童健康。 相似文献