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   2720篇
  免费   203篇
  国内免费   27篇
耳鼻咽喉   21篇
儿科学   81篇
妇产科学   75篇
基础医学   343篇
口腔科学   46篇
临床医学   277篇
内科学   702篇
皮肤病学   37篇
神经病学   368篇
特种医学   66篇
外科学   221篇
综合类   7篇
预防医学   256篇
眼科学   13篇
药学   183篇
中国医学   3篇
肿瘤学   251篇
  2024年   7篇
  2023年   53篇
  2022年   97篇
  2021年   143篇
  2020年   76篇
  2019年   102篇
  2018年   107篇
  2017年   93篇
  2016年   102篇
  2015年   119篇
  2014年   136篇
  2013年   147篇
  2012年   251篇
  2011年   236篇
  2010年   103篇
  2009年   113篇
  2008年   178篇
  2007年   174篇
  2006年   145篇
  2005年   139篇
  2004年   103篇
  2003年   105篇
  2002年   83篇
  2001年   17篇
  2000年   9篇
  1999年   15篇
  1998年   13篇
  1997年   9篇
  1996年   12篇
  1995年   9篇
  1994年   3篇
  1993年   3篇
  1992年   5篇
  1991年   7篇
  1990年   6篇
  1989年   4篇
  1988年   4篇
  1987年   3篇
  1985年   4篇
  1983年   1篇
  1982年   2篇
  1980年   1篇
  1973年   5篇
  1972年   1篇
  1970年   1篇
  1967年   1篇
  1964年   1篇
  1963年   1篇
  1960年   1篇
排序方式: 共有2950条查询结果,搜索用时 15 毫秒
71.
Study ObjectivesThe objective of this study was to evaluate the association between gestational sleep deprivation and childhood adiposity and cardiometabolic profile.MethodsData were used from two population-based birth cohorts (Rhea study and Amsterdam Born Children and their Development study). A total of 3,608 pregnant women and their children were followed up until the age of 11 years. Gestational sleep deprivation was defined as 6 or fewer hours of sleep per day, reported by questionnaire. The primary outcomes included repeated measures of body mass index (BMI), waist circumference, body fat, serum lipids, systolic and diastolic blood pressure (DBP) levels in childhood. We performed a pooled analysis with adjusted linear mixed effect and Cox proportional hazards models. We tested for mediation by birthweight, gestational age, and gestational diabetes.ResultsGestational sleep deprivation was associated with higher BMI (beta; 95% CI: 0.7; 0.4, 1.0 kg/m2) and waist circumference (beta; 95% CI: 0.9; 0.1, 1.6 cm) in childhood, and increased risk for overweight or obesity (HR; 95% CI: 1.4; 1.1, 2.0). Gestational sleep deprivation was also associated with higher offspring DBP (beta; 95% CI: 1.6; 0.5, 2.7 mmHg). The observed associations were modified by sex (all p-values for interaction < 0.05); and were more pronounced in girls. Gestational diabetes and shorter gestational age partly mediated the seen associations.ConclusionsThis is the first study showing that gestational sleep deprivation may increase offspring’s adiposity and blood pressure, while exploring possible mechanisms. Attention to glucose metabolism and preterm birth might be extra warranted in mothers with gestational sleep deprivation.  相似文献   
72.
Dengue is an emerging mosquito‐borne viral infection with increasing reports of outbreaks. The clinical picture ranges from a benign febrile illness through to severe and potentially fatal manifestations. No specific anti‐viral treatment exists, and therapy only consists of supportive care. During the last three decades, several attempts to develop an effective vaccine have been made. The first dengue vaccine to obtain licensure was Dengvaxia, which was authorized in 2015 and is currently available in over 20 countries. Its use has been approved with strict limitations regarding age and serostatus of the recipients, highlighting the necessity for a more safe and efficacious vaccine. At present several vaccine, candidates are undergoing clinical and pre‐clinical trials. The most advanced candidates are TDV and TDV 003/005, two live‐attenuated vaccines, but another 15 vaccines are under development, introducing novel immunization strategies to the traditional dengue vaccine scenario. This work reviews the current research status on dengue vaccines.  相似文献   
73.
74.
75.
Precise patterning of 2D materials into micro- and nanostructures presents a considerable challenge and many efforts are dedicated to the development of processes alternative to the standard lithography. In this work we show a fabrication technique based on direct electron beam lithography (EBL) on MoS2 on polydimethylsiloxane (PDMS) substrates. This easy and fast method takes advantage of the interaction of the electron beam with the PDMS, which at high enough doses leads to cross-linking and shrinking of the polymer. At the same time, the adhesion of MoS2 to PDMS is enhanced in the exposed regions. The EBL acceleration voltages and doses are optimized in order to fabricate well-defined microstructures, which can be subsequently transferred to either a flexible or a rigid substrate, to obtain the negative of the exposed image. The reported procedure greatly simplifies the fabrication process and reduces the number of steps compared to standard lithography and etching. As no additional polymer, such as polymethyl methacrylate (PMMA) or photoresists, are used during the whole process the resulting samples are free of residues.

Precise patterning of 2D materials into micro- and nanostructures presents a considerable challenge and many efforts are dedicated to the development of processes alternative to the standard lithography.  相似文献   
76.
Blood donor genetics and lifestyle affect the quality of red blood cell (RBC) storage. Heterozygotes for beta thalassemia (bThal+) constitute a non-negligible proportion of blood donors in the Mediterranean and other geographical areas. The unique hematological profile of bThal+ could affect the capacity of enduring storage stress, however, the storability of bThal+ RBC is largely unknown. In this study, RBC from 18 bThal+ donors were stored in the cold and profiled for primary (hemolysis) and secondary (phosphatidylserine exposure, potassium leakage, oxidative stress) quality measures, and metabolomics, versus sex- and age-matched controls. The bThal+ units exhibited better levels of storage hemolysis and susceptibility to lysis following osmotic, oxidative and mechanical insults. Moreover, bThal+ RBC had a lower percentage of surface removal signaling, reactive oxygen species and oxidative defects to membrane components at late stages of storage. Lower potassium accumulation and higher uratedependent antioxidant capacity were noted in the bThal+ supernatant. Full metabolomics analyses revealed alterations in purine and arginine pathways at baseline, along with activation of the pentose phosphate pathway and glycolysis upstream to pyruvate kinase in bThal+ RBC. Upon storage, substantial changes were observed in arginine, purine and vitamin B6 metabolism, as well as in the hexosamine pathway. A high degree of glutamate generation in bThal+ RBC was accompanied by low levels of purine oxidation products (IMP, hypoxanthine, allantoin). The bThal mutations impact the metabolism and the susceptibility to hemolysis of stored RBC, suggesting good post-transfusion recovery. However, hemoglobin increment and other clinical outcomes of bThal+ RBC transfusion deserve elucidation by future studies.  相似文献   
77.
Background: A well-balanced nutritional diet pattern has a significant role in the management of diet-related disorders. Currently, there are no specific dietary guidelines to refer to when advising non-diabetic patients with symptoms attributed to hypoglycemia in the postprandial period or patients with confirmed reactive hypoglycemia (RH). The aim of this study was to investigate the impact of the dietary interventions, and their sustained outcome, on the severity of hypoglycemic-like symptoms occurring in non-diabetic patients. Methods: The study group included forty non-diabetic individuals with symptoms consistent with RH. At the baseline, each patient underwent RH diagnosis and complex dietary evaluation. Over a period of six months, each patient had four appointments with a dietitian. Two sessions were focused on a dietary education about low glycemic index diet (LGID) and Mediterranean diet (MD). The said diets were to be followed for a period of three months, with two additional dietary check-ups. Once dietary supervision was completed, patients had no imposed dietary patterns. The final follow-up appointment took place twelve months later and that is when each patient underwent a detailed assessment of their current dietary habits and evaluation of the frequency of symptoms consistent with hypoglycemia. Results: There was a statistically significant reduction in the severity in eight out of the ten analyzed hypoglycemic-like symptoms after the dietary interventions. The most significant change was observed in the following symptoms: hunger (η2 = 0.66), impaired concentration (η2 = 0.61), hand tremor (η2 = 0.55), and fatigue (η2 = 0.51). The outcomes were comparable for both recommended diets, the LGID and the MD. The reduction in hypoglycemic-like symptoms continued after the twelve-month period. The individualized dietary counselling significantly improved the patients’ eating habits in comparison to those present prior to intervention in terms of healthy diet index (F(2,78) = 27.30, p < 0.001, η2 = 0.41, 90%CI [0.26; 0.51]) and unhealthy diet index (F(2,78) = 433.39, p < 0.001, η2 = 0.91, 90%CI [0.89; 0.93]). Conclusions: Healthy modifications in dietary habits may improve patient’s well-being and reduce the severity of their postprandial symptoms attributed to hypoglycemia. Therefore, dietary intervention focused on appropriate nutritional management combined with follow-up consultations may be a beneficial step towards comprehensive treatment of non-diabetic patients who present with hypoglycemic-like symptoms in the postprandial period.  相似文献   
78.
79.
Background and Objective  Prostate cancer (PCa) is a severe public health issue and the most common cancer worldwide in men. Early diagnosis can lead to early treatment and long-term survival. The addition of the multiparametric magnetic resonance imaging in combination with ultrasound (mpMRI-U/S fusion) biopsy to the existing diagnostic tools improved prostate cancer detection. Use of both tools gradually increases in every day urological practice. Furthermore, advances in the area of information technology and artificial intelligence have led to the development of software platforms able to support clinical diagnosis and decision-making using patient data from personalized medicine. Methods  We investigated the current aspects of implementation, architecture, and design of a health care information system able to handle and store a large number of clinical examination data along with medical images, and produce a risk calculator in a seamless and secure manner complying with data security/accuracy and personal data protection directives and standards simultaneously. Furthermore, we took into account interoperability support and connectivity to legacy and other information management systems. The platform was implemented using open source, modern frameworks, and development tools. Results  The application showed that software platforms supporting patient follow-up monitoring can be effective, productive, and of extreme value, while at the same time, aiding toward the betterment medicine clinical workflows. Furthermore, it removes access barriers and restrictions to specialized care, especially for rural areas, providing the exchange of medical images and patient data, among hospitals and physicians. Conclusion  This platform handles data to estimate the risk of prostate cancer detection using current state-of-the-art in eHealth systems and services while fusing emerging multidisciplinary and intersectoral approaches. This work offers the research community an open architecture framework that encourages the broader adoption of more robust and comprehensive systems in standard clinical practice.  相似文献   
80.
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