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61.

Objectives

Previous studies have suggested that vascular reactivity may be altered in women with polycystic ovary syndrome (PCOS). We sought to evaluate the vascular reactivity specifically the endothelial function (EF) in women with PCOS and to study the effect of metformin on their EF.

Study design

Thirty-one women diagnosed with PCOS and 33 healthy controls underwent evaluation of EF using a post-ischemia reactive hyperemia technique (Endo-PAT). EF was quantitatively determined as the ratio between the arterial pulse wave amplitude following a 5 min arterial occlusion in the forearm to the pre-occlusion value. Oral metformin 850 mg bid was administered to PCOS patients. After 3 months of treatment EF was reassessed using the same technique.

Results

The average endothelial function was 1.48 ± 0.32 in the PCOS group versus 2.00 ± 0.51 in the controls (P < 0.001). There were no significant changes in the EF among the 18 patients who were treated with metformin, EF index pre- and post-treatment was 1.42 versus 1.43, respectively.

Conclusions

Endothelial dysfunction is more likely to occur among PCOS patients than in healthy controls. These preliminary results suggest that metformin treatment for 3 months in PCOS patients does not improve endothelial function.  相似文献   
62.
PurposeTo assess the feasibility of applying ultra-widefield fundus (UWF) images for macular staphyloma area (MSA) measurement and investigate the associated factors with MSA.MethodsThis is a retrospective study. MSA was measured by UWF imaging. Central foveal thickness, subfoveal choroidal thickness, subfoveal scleral thickness were measured on spectral domain optical coherence tomography. Intraclass correlation coefficients of MSA measurement would be evaluated. Multiple linear regression analysis was used to analyze the associated factors with MSA.ResultsIn total, 135 eyes of 92 patients were enrolled. The mean age was 64.73 ± 10.84 years. Mean MSA on UWF image was 279.67 ± 71.70 mm2. Intraclass correlation coefficients of MSA measurement was 0.965 (95% confidence interval [CI], 0.946 to 0.977; p < 0.001). In the multiple linear regression analysis, after adjusting for subfoveal choroidal thickness, best-corrected visual acuity, central foveal thickness, and subfoveal scleral thickness, the factors independently related to MSA were axial length (β = 8.352; 95% CI, 3.306 to 13.398; p = 0.001), sex (β = −26.673; 95% CI, −51.759 to −1.586; p = 0.037), age (β = 1.184; 95% CI, 0.020 to 2.348; p = 0.046).ConclusionsIt is feasible to measure MSA on UWF image. Female, longer axial length, and older age may indicate larger MSA.  相似文献   
63.
Online education due to the COVID-19 pandemic caused many medical schools to increasingly employ asynchronous and virtual learning that favored student independence and flexibility. At the same time, the COVID-19 pandemic highlighted existing shortcomings of the healthcare field in providing for marginalized and underserved communities. This perspective piece details the authors’ opinions as medical students and medical educators on how to leverage the aspects of pandemic medical education to train physicians who can better address these needs.KEY WORDS: undergraduate medical education, social determinants of health, virtual learning

“American medical education needed a revolution,” writes Professor Jon M. Barry in The Great Influenza: The Story of the Deadliest Pandemic in History1. He described a different era of medical education, a time in the late 1800s when medical students graduated without having ever touched a patient. The revolution began at Johns Hopkins Hospital with William Osler’s teaching hospital model for postgraduate training, a model that spread across the nation and has formed the foundation for modern medical education2. A few decades later, the Flexner Report commissioned by the American Medical Association codified recommendations for standardized curriculum based on Osler’s program at Hopkins, giving rise to the biomedical model of medical education3, 4. In the same decade, the 1918 influenza pandemic, one of the deadliest pandemics in the history of humankind, infected approximately one-third of the world’s population, causing an estimated 50 million deaths5. Clearly, as Barry describes, it was a time of great crisis, ripe for great change.The Flexner Report and 1918 pandemic thus led to many medical schools adopting the biomedical model and overhauling their curricula. Since then, shortcomings of the Flexner Report, such as limiting the opportunities of Black physicians and excluding social determinants of health from the medical model4, 6, have been acknowledged and medical education has increasingly prioritized diversity and inclusion and public health education to better serve the diverse health needs of society79. The biopsychosocial model of medicine has largely supplanted the biomedical model7, 8, and many medical schools have modified their biomedical curricula to incorporate systems-based learning and social determinants of health.Yet healthcare is far from perfect today, with issues of cost, access, and systemic inequality still plaguing patients. As medical students and medical educators, we strive for a medical education that will better prepare the next generation of physicians to address these failures of the profession. We also have experienced how the current COVID-19 pandemic, similar to the 1918 influenza pandemic, has caused great crises in healthcare and changes in medical education1012. As vaccines have made a post-COVID era more tangible, we believe the medical field is once again ripe for revolution. In this perspective piece, we detail how we can leverage the current flux in medical education, capitalizing on asynchronous and virtual learning with a focus on social determinants and disparities, to better train physicians who will be prepared to serve the public health in a post-COVID era.  相似文献   
64.
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   
65.
Rhabdomyomas are rare benign tumors arising from skeletal muscle cells, most common cardiac in origin and usually seen in pediatric age group, often associated with neurophakomatosis like tuberous sclerosis. Extracardiac tumors are rare and are classified based on histology into adult, fetal and genital forms. The adult form of extracardiac rhabdomyoma are seen in the head and neck region in vast majority of cases. These can occur within the pharyngeal or laryngeal compartments along with other neck spaces and the orbits. In this case report, we describe the findings of adult extracardiac rhabdomyoma and discuss the striking similarity with lymphomas on imaging.  相似文献   
66.
67.
The majority of patients with advanced, high-grade epithelial-tubo ovarian cancer (EOC) respond well to initial treatment with platinum-based chemotherapy; however, up to 80% of patients will experience a recurrence. Poly(ADP-ribose) Polymerase (PARP) inhibitors have been established as a standard of care maintenance therapy to prolong remission and prevent relapse following a response to first-line platinum-chemotherapy. Olaparib and niraparib are the PARP inhibitors currently approved for use in the first-line maintenance setting in Canada. Selection of maintenance therapy requires consideration of patient and tumour factors, presence of germline and somatic mutations, expected drug toxicity profile, and treatment access. This paper discusses the current clinical evidence for first-line PARP inhibitor maintenance therapy in patients with advanced, high-grade EOC and presents consensus statements and a treatment algorithm to aid Canadian oncologists on the selection and use of PARP inhibitors within the Canadian EOC treatment landscape.  相似文献   
68.
Conductive polymeric hydrogels (CPHs) exhibit remarkable properties such as high toughness, self-recoverability, electrical conductivity, transparency, freezing resistance, stimulus responsiveness, stretch ability, self-healing, and strain sensitivity. Due to their exceptional physicochemical and physio-mechanical properties, among the widely studied CPHs, polyaniline (PANI) has been the subject of immense interest due to its stability, tunable electrical conductivity, low cost, and good biocompatibility. The current state of research on PANI hydrogel is discussed in this short review, along with the properties, preparation methods, and common characterization techniques as well as their applications in a variety of fields such as sensor and actuator manufacturing, biomedicine, and soft electronics. Furthermore, the future development and applications of PANI hydrogels are also mentioned.

Conductive polymeric hydrogels (CPHs) exhibit remarkable properties for advance technological applications.  相似文献   
69.
70.
The impact of COVID-19 vaccination on the alloimmunity of transplant candidates is unknown. We report a case of positive B cell flow cytometry crossmatch in a patient waiting for second kidney transplantation, 37 days after receiving the COVID-19 vaccine. The preliminary crossmatch, using sample collected before COVID-19 vaccination, was negative. The antibodies to mismatched donor HLA-DR7 were detected only with multi-antigen beads but not with single-antigen beads, excluding possible prozone effects in solid-phase antibody assays. The crossmatches were positive with HLA-DR7–positive surrogates (n = 2) while negative with HLA-DR7–negative surrogates (n = 3), which confirms the HLA-DR7 alloreactivity. The antigen configurations on B lymphocytes are similar to that on the multi-antigen beads while distinct from the single-antigen beads. HLA-DR7 was the repeating mismatched antigen with the failing first kidney allograft. The newly emerged antibody to HLA-DR7 probably is the consequence of bystander activation of memory response by the COVID-19 vaccination. This case highlights the importance of verifying allo-sensitization history and utilizing multiple assays, including cell-based crossmatch and solid-phase assays with multi-antigens. COVID-19 immunization may deserve special attention when assessing the immunological risk before and after organ transplantation.  相似文献   
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