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571.
Background/PurposeBidirectional trafficking of cells between the mother and the fetus is routine in pregnancy and a component of maternal-fetal tolerance. Changes in fetal-to-maternal cellular trafficking have been reported in prenatal complications, but maternal-to-fetal trafficking has never been studied in the context of fetal intervention. We hypothesized that patients undergoing open fetal surgery would have altered maternal-fetal cellular trafficking.MethodsCellular trafficking was analyzed in patients with myelomeningocele (MMC) who underwent open fetal surgical repair (n = 5), patients with MMC who had routine postnatal repair (n = 6), and healthy control healthy patients (n = 9). As an additional control for the fetal operation, trafficking was also analyzed in patients who were delivered by an ex utero intrapartum treatment procedure (n = 6). Microchimerism in maternal and cord blood was determined using quantitative real-time polymerase chain reaction for nonshared alleles.ResultsMaternal-to-fetal trafficking was significantly increased in patients who underwent open fetal surgery for MMC compared with healthy controls, patients who underwent postnatal MMC repair, and patients who underwent ex utero intrapartum treatment. There were no differences in fetal-to-maternal cell trafficking among groups.ConclusionPatients undergoing open fetal surgery for MMC have elevated levels of maternal microchimerism. These results suggest altered trafficking and/or increased proliferation of maternal cells in fetal blood and may have important implications for preterm labor.  相似文献   
572.
Objective: To identify the main characteristics of victims of motorcycle accidents in Fars Province, Iran. Methods: This cross-sectional study was conducted in Fars Province which has the fourth largest population of all 31 provinces in Iran from March 2009 to June 2010. We included data from all 542 recorded cases of fatalities due to motor vehicle accidents. Data were recorded from the forensic medicine registry consisting of demographic and accident-related information. Demographic information consisted of name, age, sex, status of fatal victim (motorcycle driver vs passenger) and educational level. Results: Of the 2 345 autopsy records from the forensic medicine archives, 542 (23.1%) gave the cause of death as motor vehicle accidents. Mean age of these victims was (31.4+/-6.5) years, and the male to female ratio was 28. Head injury was the most common cause of death in these victims, and overall they tended to have a low level of education. Motorcycle accidents frequently involved younger age groups (15-35 years), and head trauma related with non-use of a helmet was the most common cause of death. Conclusions: Head injury is frequent among victims in the province we studied. This situation may be related to the victims' low socioeconomic status and little education regarding traffic laws leading to speeding and disregard of these laws along with their weak enforcement.  相似文献   
573.
To study the function of individual neurons that are embedded in a complex neural network is difficult in mice. Conditional mutagenesis permits the spatiotemporal control of gene expression including the ablation of cells by toxins. To direct expression of a tamoxifen-inducible variant of Cre recombinase (CreERT2) selectively to cortical neurons, we replaced the coding region of the murine Nex1 gene by CreERT2 cDNA via homologous recombination in embryonic stem cells. When injected with tamoxifen, adult NEX-CreERT2 mice induced reporter gene expression exclusively in projection neurons of the neocortex and hippocampus. By titrating the tamoxifen dosage, we achieved recombination in single cells, which allowed multiphoton imaging of neocortical neurons in live mice. When hippocampal projection neurons were genetically ablated by induced expression of diphteria toxin, within 20 days the inflammatory response included the infiltration of CD3+ T cells. This marks a striking difference from similar studies, in which dying oligodendrocytes failed to recruit cells of the adaptive immune system.  相似文献   
574.
Coronary artery aneurysms are rare malformations caused by atherosclerosis, connective tissue disease or vasculitides, and are usually discovered incidentally with invasive coronary angiography. A case involving a 58-year-old male presenting with an acute coronary syndrome who was found on invasive angiogram to have a giant aneurysm of the left anterior descending coronary artery is described. The incidence, pathophysiology and management of giant aneurysms in the context of an acute coronary syndrome are reviewed.  相似文献   
575.
While brain connectivity analyses have been demonstrated to identify ill patients for a number of diseases, their ability to predict cognitive impairment after brain injury is not well established. Traditional post brain injury models, such as stroke, are limited for this evaluation because pre‐injury brain connectivity patterns are infrequently available. Patients with severe carotid stenosis, in contrast, often undergo non‐emergent revascularization surgery, allowing the collection of pre and post‐operative imaging, may experience brain insult due to perioperative thrombotic/embolic infarcts or hypoperfusion, and can suffer post‐operative cognitive decline. We hypothesized that a distributed function such as memory would be more resilient in patients with brains demonstrating higher degrees of modularity. To test this hypothesis, we analyzed preoperative structural connectivity graphs (using T1 and DWI MRI) for 34 patients that underwent carotid intervention, and evaluated differences in graph metrics using the Brain Connectivity Toolbox. We found that patients with lower binary component number, binary community number and weighted community number prior to surgery were at greater risk for developing cognitive decline. These findings highlight the promise of brain connectivity analyses to predict cognitive decline following brain injury and serve as a clinical decision support tool. Hum Brain Mapp 37:2185–2194, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
576.
Epidermolysis bullosa acquisita (EBA) is an autoimmune blistering disease characterized by autoantibodies to type VII (anchoring fibril) collagen. Therefore, it is a prototypic autoimmune disease defined by a well-known autoantigen and autoantibody. In this study, we injected hairless immune competent mice with purified immunoglobulin G (IgG) fraction of serum from rabbits immunized with the non-collagenous amino-terminal domain (NC1) of human type VII collagen, the domain known to contain immunodominant epitopes. As a control, identical mice were injected with the IgG fraction of serum from non-immunized rabbits. Mice injected with immune IgG developed subepidermal skin blisters and erosions, IgG deposits at the epidermal-dermal junction of their skin, and circulating anti-NC1 antibodies in their serum-all features reminiscent of patients with EBA. Similar concentrations of control IgG purified from normal rabbits did not induce disease in the mice. These findings strongly suggest that autoantibodies that recognize human type VII collagen in EBA are pathogenic. This murine model, with features similar to the clinical, histological, and immunological features of EBA, will be useful for the fine dissection of immunopathogenic mechanisms in EBA and for the development of new therapeutic interventions.  相似文献   
577.
578.
Purpose: To determine the distribution of near point of convergence (NPC) and its related factors in 6 to 12-year-old children. Methods: In a cross-sectional study in 2015, the urban and rural children of Shahroud, north of Iran, were sampled. All rural schoolchildren were invited to the study, and in the urban area, we conducted random cluster sampling. Examinations included measurement of uncorrected and corrected visual acuity, manifest, subjective, and cycloplegic refraction. NPC and near point of accommodation (NPA) were measured with the best optical correction. Results: Of the 6624 sampled schoolchildren, 5620 participated in the study, and after applying the exclusion criteria, the final analysis was conducted on data from 5444 students; their mean age was 9.24 ± 1.71 years (6–12 years) and 53.6% (n = 2918) of them were male. Mean NPC was 8.08 cm [95% confidence interval (CI): 7.96–8.19]; 8.07 cm (95% CI: 7.92–8.22) in males and 8.08 cm (95% CI: 7.91–8.25) in females (p = 0.954). NPC significantly recessed with age (p < 0.001). Mean NPC in emmetropic, myopic, and hyperopic children were 8.13, 7.04, and 8.23 cm, respectively (p < 0.001). The multiple linear regression model revealed significant associations for NPC with age (coefficient = 0.10, 0.95% CI: 0.05–0.15, p < 0.001), spherical equivalent refraction (coefficient = 0.17, 95% CI: 0.10–0.24, p < 0.001), and NPA (coefficient = 0.83, 0.95% CI: 0.76–0.90, p < 0.001). Conclusion: Mean NPC in 6–12-year-old Iranian children was 8.08 cm, which is worse than values reported in previous studies. Mean NPC showed a slight recession with age. Myopic schoolchildren had the least remote and hyperopes had the most remote NPC values. More remote values of NPA were associated with receded NPC.  相似文献   
579.
This study aimed to investigate the recycling opportunities for industrial byproducts and their contribution to innovative concrete manufacturing processes. The attention was mainly focused on municipal solid waste incineration fly ash (MSWI-FA) and its employment, after a washing pre-treatment, as the main component in artificially manufactured aggregates containing cement and ground granulated blast furnace slag (GGBFS) in different percentages. The produced aggregates were used to produce lightweight concrete (LWC) containing both artificial aggregates only and artificial aggregates mixed with a relatively small percentage of recycled polyethylene terephthalate (PET) in the sand form. Thereby, the possibility of producing concrete with good mechanical properties and enhanced thermal properties was investigated through effective PET reuse with beneficial impacts on the thermal insulation of structures. Based on the obtained results, the samples containing artificial aggregates had lower compressive strength (up to 30%) but better thermal performance (up to 25%) with respect to the reference sample made from natural aggregates. Moreover, substituting 10% of recycled aggregates with PET led to a greater reduction in resistance while improving the thermal conductivity. This type of concrete could improve the economic and environmental aspects by incorporating industrial wastes—mainly fly ash—thereby lowering the use of cement, which would lead to a reduction in CO2 emissions.  相似文献   
580.
Paediatric burns are a major public health issue because of long-term physical, psychological and social consequences and the high cost of treatment. The aim of this study was to design and evaluate a mobile-based self-management application for caregivers of children with severe burns. A participatory design technique was employed to develop the Burn application, which included three main phases: the determination of application requirements, the design and evaluation of the low-fidelity prototype, and the design and evaluation of the high-fidelity prototypes. In the first phase, application requirements were determined via validated paper questionnaires using the Delphi technique. In the second step, a low-fidelity prototype was prepared using conceptual models and evaluated through a focus group with specialists. Seven specialists reviewed the application and evaluated how this prototype meets functional requirements and objectives. The third phase was performed in three stages. First, the high-fidelity prototype was designed and developed by the JAVA programming language. Second, a cognitive walk-through was carried out to show how users can interact with the mobile application and how it works. Third, this program was installed on the mobile phones of 28 caregivers of burned children, eight IT experts, and two general surgeries, and the prototype's usability was evaluated. In the present study, most caregivers of children with burns stated that after discharge, they face problems regarding infection control and wound care (4.07) and how to perform physical activity (4.12). User registration, educational materials, caregiver-clinician communication, chat box, and appointment booking, safe login were the most important characteristic of the Burn application. Mean usability evaluation scores were in the range of 7.92 ± 0.238 to 8.10 ± 0.103, which is considered at a “good” level. From the Burn program design experience, it can be concluded that co-design with health care specialists can significantly support and meet the specialists' and patients' needs and ensure the program's usefulness. In addition, application evaluation by users involved and not involved in the application design process can help enhance usability.  相似文献   
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