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ObjectiveTo synthesize the evidence across longitudinal studies comparing survival in dementia with Lewy bodies (DLB) and Alzheimer’s disease (AD).MethodsWe conducted a systematic review and meta-analysis of studies comparing survival in clinically diagnosed DLB to AD. Longitudinal cohort studies were identified through a systematic search of major electronic databases from inception to May 2018. A random effects meta-analysis was performed to calculate survival time and relative risk of death.ResultsOverall, 11 studies were identified including 22,952 patients with dementia: 2029 with DLB (mean diagnosis age 76.3; 47% female) compared with 20,923 with AD (mean diagnosis age 77.2; 65.1% female). Average survival time in DLB from diagnosis was 4.11 years (SD ± 4.10) and in AD 5.66 (SD ± 5.32) years, equating to a 1.60 (95% CI: -2.44 to -0.77) years shorter survival in DLB (p < 0.01). Relative risk of death was increased by 1.35 (95%CI: 1.17–1.55) in DLB compared to AD (p < 0.01). Differences in survival were not explained by follow-up time, age at diagnosis, gender, or cognitive score.ConclusionsThere is consistent evidence for higher and earlier mortality in DLB compared to AD. This is important for all stakeholders and underlines the importance of expanding research into DLB. 相似文献
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Arabella K. Raupach Kaylena A. Ehgoetz Martens Negar Memarian George Zhong Elie Matar Glenda M. Halliday Ronald Grunstein Simon J.G. Lewis 《Journal of sleep research》2020,29(5)
The vast majority of patients with idiopathic rapid eye movement sleep behaviour disorder will develop a neurodegenerative α‐synuclein‐related condition, such as Parkinson’s disease or dementia with Lewy bodies. The pathology underlying dream enactment overlaps anatomically with the brainstem regions that regulate circadian core body temperature. Previously, nocturnal core body temperature regulation has been shown to be impaired in Parkinson’s disease. However, no study to date has investigated nocturnal core body temperature changes in patients with idiopathic rapid eye movement sleep behaviour disorder, which may prove to be an early objective biomarker for α‐synucleinopathies. Ten healthy controls, 15 patients with idiopathic rapid eye movement sleep behaviour disorder, 31 patients with Parkinson’s disease and six patients with dementia with Lewy bodies underwent clinical assessment and nocturnal polysomnography with core body temperature monitoring. A validated cosinor method was utilised for core body temperature analysis. No differences in mesor, nadir or time of nadir were observed between groups. However, when compared with healthy controls, the amplitude of the nocturnal core body temperature (mesor minus nadir) was significantly reduced in patients with idiopathic rapid eye movement sleep behaviour disorder, Parkinson’s disease with concurrent rapid eye movement sleep behaviour disorder and dementia with Lewy bodies (p < 0.001, p = 0.043 and p = 0.017, respectively). Importantly, this relationship was not seen in those patients with Parkinson’s disease without rapid eye movement sleep behaviour disorder. In addition, there was a significant negative correlation between amplitude of the core body temperature and self‐reported rapid eye movement sleep behaviour disorder symptoms. Changes in thermoregulatory circadian rhythm may be specifically associated with the pathology underlying rapid eye movement sleep behaviour disorder rather than simply that of α‐synucleinopathy. These findings implicate thermoregulatory dysfunction as a potential early biomarker for development of rapid eye movement sleep behaviour disorder‐associated neurodegeneration, and suggest that subpopulations with differing pathological underpinnings might exist in Parkinson’s disease. 相似文献
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《Journal of neuroradiology. Journal de neuroradiologie》2020,47(3):216-220
Background and purposeMultinodular and Vacuolating Neuronal Tumor of the cerebrum (MVNT) is a benign –seizure associated– lesion affecting mostly adults. This new entity has been included in the 2016 World Health Organization classification of tumors of the central nervous system.Its pathologic hallmark consist of a subcortical cluster of nodular lesions located on the subcortical white matter.We aim to report a series of cases of presumed MVNT observed in our institution and review the literature.Materials and methodsIn this retrospective study, a search was performed on our hospital information system. Sixteen cases were included. Demographic, clinical and radiological features were detailed in a table.All patients had an MRI acquired either on a 1.5 or a 3 Tesla scanner. Sequences performed included T1, T2, GRE/SWI, T2 FLAIR and DWI. Gadolinium enhanced T1-WI wer available in 11 patients and follow-up MRI were available in 7 patients.ResultsPatient ages ranged from 16 to 77 years (mean 42 years). Seizure and non-focal headache were by far the most common neurological complaints for which MRI was requested. All lesions consisted of clusters of multiple, discrete, round or ovoid, intra-axial, FLAIR and T2-WI hyperintense nodules. Follow-up MRI scans showed no changes between studies.ConclusionsMVNT is a benign, stable lesion that exhibits a typical radiological pattern that most of the times sufficed to arrive to a diagnosis, without the need of pathological confirmation. We confirm that our demographic, clinical and radiological findings are in accordance with those published in international literature. 相似文献
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Birds in the genus Pitohui and Ifrita carry potent neurotoxins that are most abundant in skin and feathers. It was unknown precisely how or where in the skin these chemicals are stored. Here, we report high‐resolution electron microscopy using OsO4 staining to visualize the location of alkaloids. Our images suggest that toxic alkaloids accumulate in multigranular bodies of epidermal cells and are likely secreted as part of the avian epidermal barrier, where they are made available for chemical defense. 相似文献
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Masaaki Taniguchi Toshiki Yoshimine Amami Kato Motohiko Maruno Norio Hirabuki Hironobu Nakamura 《Neurological research》2013,35(5):433-438
AbstractA case of dysembryoplastic neuroepithelial tumor in the left insular cortex manifesting with intractable seizures is presented. The multichannel magnetoencephalography (MEG) localized equivalent current dipoles of epileptic discharges at the cerebral cortex adjacent to the tumor. The total removal of the tumor resulted in complete disappearance of seizures. This case demonstrated that multichannel MEG was useful in the three-dimensional localization of irritative zone in the concealed cortices such as inside the sylvian fissure. [Neural Res 1998; 20: 433–438] 相似文献
59.
Harunobu Sato Tetsuya Tsukamoto Yoshihisa Mizuno Tomoaki Ichikawa Yoshihito Kotani Katsuyuki Honda Kouhei Hatta Makoto Kuroda 《Digestive endoscopy》2014,26(6):749-751
Malakoplakia in the gastrointestinal tract is rare in healthy young people without underlying disease. Sufficient tissue is required for accurate diagnosis. We describe a malakoplakia that developed in a healthy young woman and was treated by endoscopic mucosal resection (EMR). A 40‐year‐old woman with a history of taking oral contraceptives until one year earlier was referred to our hospital with anal bleeding and constipation. A colonoscopy carried out at our another hospital 18 months earlier disclosed no abnormal findings. Colonoscopy at presentation revealed a yellowish‐white tumor, 5 mm in diameter, in the rectum. The lesion was slightly protruded and had a smooth flat surface, without erosion or ulceration. EMR was carried out for a definitive diagnosis. Histopathological examination showed that the tumor contained granular histiocytes, positive for CD68 and negative forcytokeratin (AE1/AE3). Several histiocytes contained intracytoplasmic round bodies (Michaelis–Gutmann bodies), which reacted positively with periodic acid‐Schiff and calcium (Von Kossa) stains. Intracytoplasmic Escherichia coli (von Hansemann bodies) were identified by Giemsa staining. Based on these results, the tumor in the rectum was diagnosed as a malakoplakia. Following EMR, the patient did not receive further treatment for malakoplakia because she had no symptoms associated with malakoplakia. She has been well for more than 9 months, with no symptoms of disease. Awareness of colorectal malakoplakia is important in patients taking steroids, including oral contraceptives. 相似文献
60.
Gregor K. Wenning MD PhD MSc Irene Litvan MD Eduardo Tolosa MD 《Movement disorders》2011,26(6):1083-1095
During the last decades, atypical parkinsonian disorders such as multiple system atrophy, dementia with Lewy bodies, progressive supranuclear palsy, and corticobasal degeneration along with secondary parkinsonian disorders have been increasingly recognized as important causes of parkinsonism. Although treatment options are largely limited to date, remarkable progress has occurred through advances in the fields of molecular biology and diagnostic neuroimaging, resulting in intense preclinical drug discovery programs. Early‐investigation‐assisted clinical diagnosis has become more crucial than ever because disease‐modifying therapies will hopefully become available within this decade. © 2011 Movement Disorder Society 相似文献