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21.
Images can be distorted in the real world via many sources like faulty sensors, artifacts generated by compression algorithms, defocus, faulty lens, and poor lighting conditions. Our biological vision system can identify the quality of image by looking at the images, but developing an algorithm to assess the quality of an image is a very challenging task as an image can be corrupted by different types of distortions and statistical properties of different types of distortions are dissimilar. The main objective of this article is to propose an image quality assessment technique for images corrupted by blurring and compression-based artifacts. Machine learning-based approaches have been used in recent times to perform this task. Images can be analyzed in different transform domains like discrete cosine transform domain, wavelet domains, curvelet domains, and singular value decomposition. These domains generate sparse matrices. In this paper, we propose no-reference image quality assessment algorithms for images corrupted by blur and different compression algorithms using sparsity-based features computed from different domains and all features pooled by support vector regression. The proposed model has been tested on three standard image quality assessment datasets LIVE, CSIQ, and TID2013, and correlation with subjected human opinion scores has been presented along with comparative study with state-of-the-art quality measures. Experiments run on standard image quality databases show that the results obtained are outperforming the existing results.  相似文献   
22.
White spot syndrome virus (WSSV) is a large dsDNA virus responsible for white spot disease in shrimp and other crustaceans. VP28 is one of the major envelope proteins of WSSV and plays a crucial role in viral infection. In an effort to develop a vaccine against WSSV, we have constructed a recombinant baculovirus with an immediate early promoter 1 which expresses VP28 at an early stage of infection in insect cells. Baculovirus expressed rVP28 was able to maintain its structural and antigenic conformity as indicated by immunofluorescence assay and western blot analysis. Interestingly, our results with confocal microscopy revealed that rVP28 was able to localize on the plasma membrane of insect cells infected with recombinant baculovirus. In addition, we demonstrated with transmission electron microscopy that baculovirus successfully acquired rVP28 from the insect cell membrane via the budding process. Using this baculovirus displaying VP28 as a vaccine against WSSV, we observed a significantly higher survival rate of 86.3% and 73.5% of WSSV-infected shrimp at 3 and 15 days post vaccination respectively. Quantitative real-time PCR also indicated that the WSSV viral load in vaccinated shrimp was significantly reduced at 7 days post challenge. Furthermore, our RT-PCR and immunohistochemistry results demonstrated that the recombinant baculovirus was able to express VP28 in vivo in shrimp tissues. This study will be of considerable significance in elucidating the morphogenesis of WSSV and will pave the way for new generation vaccines against WSSV.  相似文献   
23.
MicroRNA (miRNA) are small non-coding RNA molecules about 21-25 nucleotides long. They control gene regulation by translational repression and cleavage. Several studies have shown that many miRNA are associated with the etiology of different diseases. Recent developments in diverse miRNA profiling platforms like microarray and quantitative real-time PCR may enable the identification of specific miRNA as novel diagnostic and predictive markers for various diseases. MiRNAs could even be used as therapeutic drug targets. Multiple sclerosis (MS) is a chronic autoimmune disease affecting the central nervous system. Dysregulated immune system processes result in demyelination of neurons and consequently, electrical impulses that travel along the nerves are disrupted resulting in the impairment of organs. In the past three years, there has been an increased interest in establishing miRNA-based biomarkers for MS. So far, there are six studies on miRNA expression in MS patients in which first miRNAs were discovered as potential disease markers. For instance, one study showed that blood levels of miR-145 can discriminate MS patients from healthy controls, and another showed that active lesions in the brain are characterized by a strong up-regulation of miR-155. Studies on experimental autoimmune encephalomyelitis (EAE), the animal model of MS, further support the significance of miRNA as e.g. mice with miR-155 deletion are highly resistant to EAE. Such investigations help to understand the molecular processes involved in the disease. The identification of miRNA markers that are associated with type of MS, individual disease activity or clinical progression under treatment may open new avenues for early diagnosis and optimized therapy of MS.  相似文献   
24.
Peripheral artery disease (PAD) results from progressive narrowing of arteries secondary to atherosclerosis and is defined as an Ankle Brachial Index of <0.9. PAD is highly prevalent and is an increasing burden on both the economy and the patient, especially given the rapid shift in demographics in the United States. Despite its prevalence and association with cardiovascular disease, PAD is still underdiagnosed and undertreated. This may, in part, be related to lack of recognition from the physician's side or paucity of evidence from clinical trials. It has been shown that medical therapy approved for cardiovascular disease is effective in the treatment of PAD and decreases cardiovascular events. Various revascularization strategies are also available for improving symptoms and quality of life in these patients, yet they are underutilized. In an attempt to increase its recognition, PAD has been considered a coronary artery disease equivalent. This article reviews the diagnosis and management of PAD. © 2011 Wiley Periodicals, Inc. The authors have no funding, financial relationships, or conflicts of interest to disclose.  相似文献   
25.
Persons aged 65 years or older, often referred to as the elderly, are a rapidly increasing population in the United States. Cardiovascular disease is the most common cause of morbidity and death in this age group, and acute coronary syndrome accounts for a significant proportion of the deaths. Percutaneous coronary intervention is a well-established treatment for acute coronary syndrome and symptomatic coronary artery disease. However, community studies have shown that elderly patients are less likely to undergo revascularization, perhaps due to a "treatment-risk" paradox: elderly patients-at higher risk of morbidity and death from acute coronary syndrome-are denied revascularization even though they are likely to benefit from it. Age alone is one of the many reasons why percutaneous coronary intervention is avoided in elderly patients. This review examines past clinical trials and the existing evidence that supports performing percutaneous coronary intervention in elderly patients.  相似文献   
26.
In 2010, the World Health Organization Global Code of Practice for International Recruitment of Health Personnel (the WHO Code) was adopted by the 193 Member States of the WHO. The WHO Code is a tool for global diplomacy, providing a policy framework to address the challenges involved in managing dentist migration, as well as improving the retention of dental personnel in source countries. The WHO Code recognizes the importance of migrant dentist data to support migration polices; minimum data on the inflows, outflows and stock of dentists are vital. Data on reasons for dentist migration, job satisfaction, cultural adaptation issues, geographic distribution and practice patterns in the destination country are important for any policy analysis on dentist migration. Key challenges in the implementation of the WHO Code include the necessity to coordinate with multiple stakeholders and the lack of integrated data on dentist migration and the lack of shared understanding of the interrelatedness of workforce migration, needs and planning. The profession of dentistry also requires coordination with a number of private and nongovernmental organizations. Many migrant dentist source countries, in African and the South‐Asian WHO Regions, are in the early stages of building capacity in dentist migration data collection and research systems. Due to these shortcomings, it is prudent that developed countries take the initiative to pursue further research into the migration issue and respond to this global challenge.  相似文献   
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28.
Background: Polypharmacy has been reported to increase the risks for inappropriate prescribing, adverse drug reactions, geriatric syndromes, and morbidity and mortality in elderly populations in the United States and Europe. Data on prescribing patterns and polypharmacy in the elderly population in India are limited.Objectives: The aims of this study were to assess prescribing patterns and to determine the predictors of high-level polypharmacy in the elderly population in 2 tertiary care hospitals in India.Methods: This prospective surveillance study used medical records from patients aged 60 to 95 years admitted to the medicine wards of the 2 tertiary care hospitals between January 2008 and June 2009. Data on medication prescribing from admission through discharge were reviewed. Diseases were coded using the World Health Organization (WHO) International Classification of Diseases, 10th Revision, and medications were coded using the WHO Anatomical, Therapeutic, and Chemical classification. Concordance of prescribing with the indications in the product labeling as listed in the American Hospital Formulary Services Drug Information 2007 was determined. The prevalences of polypharmacy (5–9 medications) and high-level polypharmacy (≥10 medications) were determined. Bivariate analysis and multivariate logistic regression analysis were used to determine the influential predictors of high-level polypharmacy during hospital stays.Results: Data from 814 patients were included (493 [60.6%] men, 321 [39.4%] women; median age, 66 years [range, 60–95 years]). Systemic antibacterials were the most commonly prescribed therapeutic class of medications (574 [70.5%]), and pantoprazole was the most commonly prescribed medication (498 [61.2%]). The majority (7/10 [70.0%]) of the most commonly prescribed medications were prescribed as indicated. Medications prescribed “off-label” included pantoprazole (432/498 [86.7%]), ceftriaxone (212/259 [81.9%]), and atorvastatin (109/237 [46.0%]). Polypharmacy and high-level polypharmacy were prescribed in 366 (45.0%) and 370 (45.5%) patients, respectively. On multivariate logistic regression analysis, multiple (≥3) diagnoses (odds ratio [OR] = 1.55; 95% CI, 1.16–2.08; P = 0.003), angina pectoris (OR = 2.58; 95% CI, 1.50–4.37; P < 0.001), and a length of stay ≥10 days (10–<15 days, OR = 3.14; 95% CI, 2.09–4.71; P < 0.001; and ≥15 days, OR = 5.74; 95% CI, 2.43–13.51; P < 0.001) were found to be predictors of high-level polypharmacy during hospital stays.Conclusions: The campaign for rational drug use in hospitalized elderly patients in India should promote pantoprazole, ceftriaxone, and atorvastatin prescribing in concordance with their indications. Interventions to reduce the high-level polypharmacy in the elderly during their stays in tertiary care hospitals in India should focus on patients with ≥3 diagnoses, angina pectoris, and/or ≥10 days of hospital stay.  相似文献   
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30.
The aim of our study was to assess the attitudes of postgraduate orthodontic students in India towards patient-centered care. Two hundred and two students from eighteen dental schools across India completed the modified Patient-Practitioner Orientation Scale (PPOS), a self-administered eighteen-item questionnaire that evaluates the practice orientation of the students in terms of doctor versus patient-centeredness. The results revealed that the attitudes of the orthodontic postgraduate students in India were generally more doctor-centered (mean PPOS score of 3.38). As compared to their male counterparts, the female students were more considerate of the role of psychosocial factors in health and the importance of warm doctor-patient relationships (mean caring subscale score of 3.8 vs. 3.54, p<0.05). The third-year students were relatively more patient-centered than their first-year colleagues (mean PPOS score of 3.56 vs. 3.27, p<0.05) and were more willing to share power and information with their patients (mean sharing score of 3.24 vs. 2.92, p<0.01). In general, the students became more patient-centered as they progressed through their postgraduate course. The results of the study clearly imply the need for more active measures in order to develop a more patient-centered orthodontic health care system in India.  相似文献   
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