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1.
A case of hemangiopericytoma in the male pelvis is presented in which computed tomography demonstrated a well-circumscribed, homogeneous enhancing mass with feeding vessels.  相似文献   
2.
Compound nerve action potential (CNAP) of the mixed peripheral nerve is composed of A alpha beta, A delta, and C potentials. All components of CNAPs in the sciatic nerve were recorded by stimulating the tibial nerve of both control and lead-poisoned rats. Marked decrease of nerve conduction velocity and prolonged duration were found in A alpha beta and A delta fibers especially in large myelinated A alpha beta fibers. The amplitude decreased in A alpha beta potential, but the area did not change. In C potential produced by activation of unmyelinated fibers, nerve conduction velocity slightly decreased, but the amplitude and area did not significantly change. Pathologic correlates revealed prominent segmental demyelination with significant decrease of large myelinated fiber densities. Minimal axonal degeneration of unmyelinated fibers was present. We can conclude that electrophysiologic changes in the lead-poisoned rats correlate with pathologic changes in them.  相似文献   
3.
Dengue and the more severe dengue hemorrhagic fever have been a very critical public health problem globally. Millions of people especially in the tropical areas get infected with dengue. An efficient diagnostic is very important for early screening of dengue infection. In dengue-infected patients, the nonstructural protein NS1 is present on the surface of infected cells and secreted in plasma. The NS1 antigen is an important target for developing a quick diagnostic largely due to its long presence in the blood. We have developed a simple-to-use immunoswab-based diagnostic procedure employing monoclonal antibodies and the second-generation quadromas. The detection limit for NS1 has been established to be in the subnanogram range. The assay is very sensitive, has a visual end point, and also being extremely inexpensive. With this assay, screening time for a dengue-infected person would be very rapid.  相似文献   
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Cochlear implant (CI) users with a prelingual onset of hearing loss show poor sensitivity to interaural time differences (ITDs), an important cue for sound localization and speech reception in noise. Similarly, neural ITD sensitivity in the inferior colliculus (IC) of neonatally-deafened animals is degraded compared with animals deafened as adults. Here, we show that chronic bilateral CI stimulation during development can partly reverse the effect of early-onset deafness on ITD sensitivity. The prevalence of ITD sensitive neurons was restored to the level of adult-deaf (AD) rabbits in the early-deaf rabbits of both sexes that received chronic stimulation and behavioral training with wearable bilateral sound processors during development. We also found a partial improvement in neural ITD sensitivity in the early-deaf and stimulated rabbits compared with unstimulated rabbits. In contrast, chronic CI stimulation did not improve temporal coding in early-deaf rabbits. The present study is the first report showing functional restoration of ITD sensitivity with CI stimulation in single neurons and highlights the importance of auditory experience during development on the maturation of binaural circuitry.SIGNIFICANCE STATEMENT Although cochlear implants (CI) are highly successful in providing speech reception in quiet for many profoundly deaf people, CI users still face difficulty in noisy everyday environment. This is partly because of their poor sensitivity to differences in the timing of sounds arriving at the two ears [interaural time differences (ITDs)], which help to identify where the sound is coming from. This problem is especially acute in those who lost hearing early in life. Here, we present the first report that sensitivity of auditory neurons to ITDs is restored by CI stimulation during development in an animal model of neonatal deafness. These findings highlight the importance of providing early binaural auditory experience with CIs in deaf children.  相似文献   
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The COVID‐19 pandemic has placed an extraordinary demand on the United States health care system. Many institutions have canceled elective and non‐urgent procedures to conserve resources and limit exposure. While operational definitions of elective and urgent categories exist, there is a degree of surgeon judgment in designation. In the present commentary, we provide a framework for prioritizing head and neck surgery during the pandemic. Unique considerations for the head and neck patient are examined including risk to the oncology patient, outcomes following delay in head and neck cancer therapy, and risk of transmission during otolaryngologic surgery. Our case prioritization criteria consist of four categories: urgent—proceed with surgery, less urgent—consider postpone > 30 days, less urgent—consider postpone 30 to 90 days, and case‐by‐case basis. Finally, we discuss our preoperative clinical pathway for transmission mitigation including defining low‐risk and high‐risk surgery for transmission and role of preoperative COVID‐19 testing.  相似文献   
8.
Oral cancer is on the rise globally and survival rates, despite improvements in clinical care, have not significantly improved. Early detection followed by immediate intervention is key to improving patient outcomes. The use of biomarkers has changed the diagnostic landscape for many cancers. For oral cancers, visual inspection followed by a tissue biopsy is standard practice. The discovery of microRNAs as potential biomarkers has attracted clinical interest but several challenges remain. These microRNAs can be found in bodily fluids such as blood and saliva which have been investigated as potential sources of biomarker discovery. As oral cancer is localized within the oral cavity, saliva may contain clinically relevant molecular markers for disease detection. Our review provides an outline of the current advances for the application of salivary microRNAs in oral cancer. We also provide a technical guide for the processing of salivary RNAs to ensure accurate clinical measurement and validation.  相似文献   
9.
Cerebral microbleeds (CMBs) are known to be associated with cognitive impairments in the elderly and in patients with various diseases; however, the nature of this association has not yet been evaluated in Parkinson’s disease (PD). In the present study, we analyzed the incidence of CMBs in PD according to cognitive status, and the impact of CMBs on cognitive performance was also evaluated. The CMBs in PD with dementia (n = 36), mild cognitive impairment (MCI, n = 46), or cognitively normal (n = 41) were analyzed using conventional T2*-weighted gradient-recalled echo images. Additionally, the relationship between the presence of CMBs and cognitive performance on individual tests of cognitive subdomains was analyzed using a detailed neuropsychological test. CMBs occurred more frequently in PD patients with dementia (36.1 %) compared to those with MCI (15.2 %), those who are cognitively normal (14.6 %), and normal controls (12.2 %, p = 0.025). However, the significant association of CMBs with PD dementia disappeared after adjusting white matter hyperintensities (WMHs) as a covariate. The frequencies of deep, lobar, and infratentorial CMBs did not differ among the four groups. After adjusting for age, sex, years of education, and WMHs, PD patients with CMBs had poorer performance in attention domain compared with those without CMBs (34.9 vs 42.6, p = 0.018). The present data demonstrate that even though CMBs were inseparably associated with the presence of WMHs, CMBs occur more commonly in PD patients with dementia than in those without dementia. Additionally, the burden of CMBs may contribute to further cognitive impairment in PD.  相似文献   
10.
Loss of heterozygosity studies of a variety of human tumors suggest that there are several tumor suppressor genes on chromosome arm 8p. To localize these genes more precisely, we utilized polymerase chain reaction amplification of microsatellite repeat polymorphisms and examined the allelic loss patterns of 17 marker loci on 8p in a population of 59 supraglottic laryngeal squamous cell carcinomas. Twenty-three of these tumors (39%) had an allelic loss at one or more of the markers examined. The allelic loss patterns of these tumors support the presence of at least three different tumor suppressor genes on 8p: one in 8p23, one in 8p22–23, and another in 8p21. Genes Chromosom Cancer 16:164–169 (1996). © 1996 Wiley-Liss, Inc.  相似文献   
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