全文获取类型
收费全文 | 501篇 |
免费 | 28篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 25篇 |
妇产科学 | 13篇 |
基础医学 | 103篇 |
口腔科学 | 11篇 |
临床医学 | 65篇 |
内科学 | 115篇 |
皮肤病学 | 8篇 |
神经病学 | 45篇 |
特种医学 | 11篇 |
外科学 | 43篇 |
综合类 | 9篇 |
预防医学 | 12篇 |
眼科学 | 23篇 |
药学 | 37篇 |
中国医学 | 3篇 |
肿瘤学 | 12篇 |
出版年
2024年 | 1篇 |
2023年 | 3篇 |
2022年 | 17篇 |
2021年 | 45篇 |
2020年 | 22篇 |
2019年 | 12篇 |
2018年 | 27篇 |
2017年 | 23篇 |
2016年 | 19篇 |
2015年 | 20篇 |
2014年 | 21篇 |
2013年 | 30篇 |
2012年 | 43篇 |
2011年 | 44篇 |
2010年 | 25篇 |
2009年 | 35篇 |
2008年 | 25篇 |
2007年 | 25篇 |
2006年 | 25篇 |
2005年 | 16篇 |
2004年 | 14篇 |
2003年 | 12篇 |
2002年 | 6篇 |
2001年 | 7篇 |
2000年 | 10篇 |
1999年 | 5篇 |
1998年 | 1篇 |
1996年 | 1篇 |
1990年 | 1篇 |
1979年 | 1篇 |
排序方式: 共有536条查询结果,搜索用时 15 毫秒
1.
The finite element model for the propagation of light in scattering media: a direct method for domains with nonscattering regions 总被引:2,自引:0,他引:2
We present a method for handling nonscattering regions within diffusing domains. The method develops from an iterative radiosity-diffusion approach using Green's functions that was computationally slow. Here we present an improved implementation using a finite element method (FEM) that is direct. The fundamental idea is to introduce extra equations into the standard diffusion FEM to represent nondiffusive light propagation across a nonscattering region. By appropriate mesh node ordering the computational time is not much greater than for diffusion alone. We compare results from this method with those from a discrete ordinate transport code, and with Monte Carlo calculations. The agreement is very good, and, in addition, our scheme allows us to easily model time-dependent and frequency domain problems. 相似文献
2.
David P. Bazett-Jones Ren Li Eden Fussner Rosa Nisman Hesam Dehghani 《Chromosome research》2008,16(3):397-412
Electron microscopy has been the ‘gold standard’ of spatial resolution for studying the structure of the cell nucleus. Electron
spectroscopic imaging (ESI) offers advantages over conventional transmission electron microscopy by eliminating the need for
heavy-atom contrast agents. ESI also provides mass-dependent and element-specific information at high resolution, permitting
the distinguishing of structures that are primarily composed of protein, DNA, or RNA. The technique can be applied to understand
the structural consequences of epigenetic modifications, such as modified histones, on chromatin fiber morphology. ESI can
also be applied to elucidate the multifunctional behavior of subnuclear ‘organelles’ such as the nucleolus and promyelocytic
leukemia nuclear bodies.
The authors dedicate this paper to the memory of Ying Ren (1961–2007). We all benefited from knowing her. Our research advanced
through the technical creativity she provided. 相似文献
3.
Ashish Soni Pankaj Kumar Das Abdul Wahab Hashmi Mohammad Yusuf Hesam Kamyab Shreeshivadasan Chelliapan 《Sustainable Chemistry and Pharmacy》2022
Strict environmental concern, depletion, and price hike of building construction materials are driving scientific studies for the search of alternative materials for building construction. To this end sustainable building materials could be a fruitful solution. This review aims to discern the environmental efficacy of solid waste management (SWM) and its relationship with four stimuli i.e., economic structure, regulatory structure, science, and time. The study also highlights the investigation of governance network to figure out the regulatory structure and governance of waste management. Extensive details on solid waste with their sources, recycling potential and their current utilization for substantial development are outlined. A throughout of the production process, properties, advantages, disadvantages, and the global economy of building material developed through recycling of solid waste are discussed. This article also deals with the sustainability, social, and environmental impact of green building materials. The study identifies the future direction for the effective utilization of solid waste for developing building materials. Further, the scope of the present also focusses on the concept of circular economy for developing construction materials through recycling of solid waste, which provides an easy reference for solid waste processing towards sustainability. 相似文献
4.
Behrooz Nikahval Seifollah Dehghani Nazhvani Mohammad Hadi Bagheri Nader Tanideh Mehrangiz Keramati Hamid Reza Gheisari 《Comparative clinical pathology》2012,21(6):1451-1456
The objectives of the present study were to describe radiographic and magnetic resonance imaging (MRI) findings of early osteoarthritis and their relationships at the same time. A total number of ten rabbits were used and randomly divided into two equal groups. In one group, cranial cruciate ligament (CCL) of the left knee was transected to produce experimental osteoarthritis and in the other group, only the articular capsule was entered as sham operation (arthrotomy group). All of the left knees were examined by MRI and radiography before operation to exclude preexisting abnormalities and serve as control. One month postoperation, two conventional radiographic views and MR imaging were performed under general anesthesia. Statistical analysis of the MRI results revealed that there was a significant difference between the CCL-transected group with arthrotomy and control groups. There was no significant difference in the radiographic findings between the operated, arthrotomy and control groups. It was concluded that osteoarthritic changes of the joints can be detectable 1?month postinjury by MRI. Meniscal degeneration and subchondral bone irregularity are detectable diagnostic signs. 相似文献
5.
High rate of A2142G point mutation associated with clarithromycin resistance among Iranian Helicobacter pylori clinical isolates 下载免费PDF全文
Reza Khashei Mahintaj Dara Abdollah Bazargani Kamran Bagheri Lankarani Alireza Taghavi Maryam Moeini Behzad Dehghani Maryam Sohrabi 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2016,124(9):787-793
This study aimed to investigate the clarithromycin resistance and its associated molecular mechanisms among Helicobacter pylori isolates from dyspeptic patients in Shiraz, Iran. From January to May 2014, 100 H. pylori strains were isolated from patients with gastroduodenal disorders. The resistance to clarithromycin was quantitatively evaluated, using Epsilometer (E‐test) method. Polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) was performed on all the isolates to detect A2143G and A2142G mutations in 23S rRNA gene. The H. pylori isolation rate was found to be 31.4%. E‐test showed that 20% of isolates were resistant to clarithromycin (MIC ≥ 1 mg/L). MIC of clarithromycin ranged between 0.016 and 24 mg/L. Findings of PCR‐RFLP showed that the A2142G was the most (90%) frequently point mutation, followed by the A2143G (10%). No statistically significant difference was found between H. pylori clarithromycin resistance point mutations and patients’ gender or age. To the best of our knowledge, this is the first report of high frequency of A2142G point mutation in Iran and probably in other regions of the world. Considering the increasing trend of H. pylori resistance to clarithromycin due to these mutations, it is crucial to investigate the new therapeutic approaches against H. pylori infection. 相似文献
6.
7.
Disasters are fortunately rare occurrences. However, accurate and timely information and communication are vital to adequately
prepare individual health organizations for such events. The current article investigates the health related communication
and information systems for emergency management in Iran. A mixed qualitative and quantitative methodology was used in this
study. A sample of 230 health service managers was surveyed using a questionnaire and 65 semi-structured interviews were also
conducted with public health and therapeutic affairs managers who were responsible for emergency management. A range of problems
were identified including fragmentation of information, lack of local databases, lack of clear information strategy and lack
of a formal system for logging disaster related information at regional or local level. Recommendations were made for improving
the national emergency management information and communication system. The findings have implications for health organizations
in developing and developed countries especially in the Middle East. Creating disaster related information databases, creating
protocols and standards, setting an information strategy, training staff and hosting a center for information system in the
Ministry of Health to centrally manage and share the data could improve the current information system. 相似文献
8.
Arash Arya Majid Haghjoo Zahra Emkanjoo Mohammad Reza Dehghani Mohammad Ali Sadr-Ameli 《Journal of interventional cardiac electrophysiology》2006,17(1):59-63
Objective We conducted this study to compare the rate of ≥1 inappropriate therapy between ICDs from two manufacturers which use different
discriminatory protocols.
Method One hundred sixty two patients (mean age 58 ± 13 years, 126 male) who received ICDs between January 2001 and 2005 were included
in the study. Clinical, electrocardiographic, and ICD stored data and electrograms were collected and analyzed. Immediately
after implantation all the detection and discrimination criteria were activated with the nominal values in order to compare the two discriminatory protocols under the default manufacturer’s settings.
Results During the follow up period of 14.3 ± 10 months, 49 (30%) patients received ≥1 inappropriate ICD therapy. The rate of ≥1 inappropriate
ICD therapy in manufacturer A and B ICDs was 26% (n = 29) and 41% (n = 20), respectively. Comparing the rate of ≥1 inappropriate ICD therapy between the two groups by Kaplan–Meier analysis and
the log rank test resulted in P = 0.04.
Conclusion Having all discriminatory variables activated with the nominal values, discriminatory performance differs between the two manufacturers. Further larger-scale studies are warranted to prospectively
compare the performance of various available ICDs’ discriminatory protocols, and define the optimum combination of discriminators in each ICD to decrease the rate of inappropriate therapy. 相似文献
9.
Liver transplantation as a definitive treatment for familial hypercholesterolemia: A series of 36 cases 下载免费PDF全文
Mohsenreza Mansoorian Kourosh Kazemi Saman Nikeghbalian Alireza Shamsaeefar Maral Mokhtari Seyed Mohsen Dehghani Ali Bahador Heshmatollah Salahi Hamid Amoozgar Seyed Ali Malek Hosseini 《Pediatric transplantation》2015,19(6):605-611
FH is a genetic disorder characterized by an increase in serum LDL and total cholesterol values. The afflicted patients are at increased risk of premature atherosclerosis and myocardial infarction. Different treatment modalities are present, including pharmacological agents and surgical procedures. The most effective method of therapy in refractive cases is liver transplantation. Herein, we report our experience on 36 cases of patients with FH undergoing liver transplantation in our center, the main referral center of liver transplantation in Iran. The clinical findings, hospital courses, post‐operative complications, and patient follow‐up are also described. 相似文献