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61.
《Experimental and toxicologic pathology》2014,66(1):73-80
This work aims at characterizing rat mammary tumors induced by 7,12-dimethylbenz(a)anthracene (DMBA) and the respective malignancy potential, commonly graded with histopathology features grouped by intensity levels. Tumors were described over fourteen multiple ranged microscopic parameters and a comprehensive characterization of the histological patterns and their relation with tumor grade was carried out by principal component analysis (PCA). The number of histological patterns present on a tumor tends to correlate with malignant features. High grade tumors are characterized by the presence of several structural patterns, with cribriform prevalence and necrosis. The cribriform pattern correlates with grading, i.e., tumors having a higher predominance of the cribriform pattern are likely to be more malignant. The findings may represent a benchmark for similar characterization studies in other models. 相似文献
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63.
《Acta biomaterialia》2014,10(8):3599-3614
The scales of the arapaima (Arapaima gigas), one of the largest freshwater fish in the world, can serve as inspiration for the design of flexible dermal armor. Each scale is composed of two layers: a laminate composite of parallel collagen fibrils and a hard, highly mineralized surface layer. We review the structure of the arapaima scales and examine the functions of the different layers, focusing on the mechanical behavior, including tension and penetration of the scales, with and without the highly mineralized outer layer. We show that the fracture of the mineral and the stretching, rotation and delamination of collagen fibrils dissipate a significant amount of energy prior to catastrophic failure, providing high toughness and resistance to penetration by predator teeth. We show that the arapaima’s scale has evolved to minimize damage from penetration by predator teeth through a Bouligand-like arrangement of successive layers, each consisting of parallel collagen fibrils with different orientations. This inhibits crack propagation and restricts damage to an area adjoining the penetration. The flexibility of the lamellae is instrumental to the redistribution of the compressive stresses in the underlying tissue, decreasing the severity of the concentrated load produced by the action of a tooth. The experimental results, combined with small-angle X-ray scattering characterization and molecular dynamics simulations, provide a complete picture of the mechanisms of deformation, delamination and rotation of the lamellae during tensile extension of the scale. 相似文献
64.
胡冰 《临床超声医学杂志》2018,20(9)
目的 探索性研究子宫输卵管超声造影中输卵管通而不畅的分级方法及其临床意义。 相似文献
65.
《Journal of family psychotherapy》2013,24(1-2):223-228
Summary This article discusses the use of solution-focused supervision questions and their perceived effect on a class of counseling practicum students. Rating scales have been used as a tool to evaluate therapist development since the 1960s. In this case study, questions were asked of student therapists from the perspective of the client. Student reports find that the questions were beneficial in helping direct future sessions toward client goals. 相似文献
66.
Ji Hyun Lee Chae Young Won Gyong Moon Kim Si Yong Kim 《The Journal of dermatology》2014,41(6):487-493
Actinic keratosis (AK) is a common precursor of sun‐related squamous cell carcinoma. AK is difficult to be differentiated from other malignancies with the naked eyes. Dermoscopic features of AK were previously described in some studies, but not extensively investigated. We investigated the dermoscopic features of AK in Asians and assessed dermoscopy as a post‐treatment monitoring tool of AK. We retrospectively examined 34 AK lesions which had been diagnosed by histology. The changes of dermoscopic features and histopathological findings were assessed in all these lesions before and after treatment. Before treatment, 18 lesions were pigmented and 16 lesions were non‐pigmented AK dermoscopically. The frequent dermoscopic features of AK were keratin/scales (79.4%), red pseudonetwork (73.5%), targetoid‐like appearance (55.9%), rosette sign (38.2%) and absent fissures/ridges, crypts and milia‐like cysts. All the lesions had been treated with either photodynamic therapy, cryotherapy or 5% imiquimod cream. After treatment, dermoscopic features of 33 AK lesions were decreased or disappeared, and skin biopsies confirmed that atypical keratinocytes disappeared. One lesion showed accentuated and new dermoscopic features after treatment, and skin biopsy also showed progressing squamous cell carcinoma. In conclusion, scales, red pseudonetwork, targetoid‐like appearance and rosette sign were common dermoscopic findings of AK in Asians. In most cases, the treatment response correlated with the changes in dermoscopic features. These findings suggest that dermoscopy is a useful tool to monitor AK. 相似文献
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68.
Tumour budding activity and cell nest size determine patient outcome in oral squamous cell carcinoma: proposal for an adjusted grading system 下载免费PDF全文
69.
Arrhythmogenic properties of disordered breathing during sleep in patients with cardiovascular disorders 总被引:1,自引:0,他引:1
The purpose of this study was twofold: to establish an ECG respiration monitoring system, and to evaluate the clinical usefulness of this system. Our purpose was to determine how many patients with cardiovascular disorders may have unrecognized sleep apnea and whether such apneic episodes are an important cause of cardiac arrhythmias. The study group included 81 patients, age range 40-95 years, and 13 healthy males, age range 52-72 years. The 24-h ECG respiration recordings were obtained with the two-channel holter recorder. Airflow at the nose using a nasal thermister or chest wall movement by impedance pneumography was recorded as respiration record on the second channel. Sleep apnea was observed 69% and 77-100% in the control subjects and patients with cardiovascular disorders, respectively. Episodes of sleep apnea were most frequent in the patients with old myocardial infarction. Grading of apneas was defined according to the length of apnea. Short duration apneas were observed only in the control subjects, but longer apneic episodes were observed in patients with cardiovascular disorders. Bradyarrhythmias observed were to be relative to apneic episodes longer than 20 s, while ventricular arrhythmias were observed only in the patients with old myocardial infarction, coincident with apneas lasting longer than 40 s. Atrioventricular conduction disturbances were also observed to be related to the occurrence of sleep apnea. These results suggest that 24-h ECG respiration monitoring is useful not only for the observation of sleep apneic episodes, but also in clarifying the relationship between cardiac arrhythmias and apneic episodes. 相似文献
70.