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1.
Using 4 and 8-channel super-parallel magnetic resonance (MR) microscopes with a horizontal bore 2.34T superconducting magnet developed for 3-dimensional MR microscopy of the large Kyoto Collection of Human Embryos, we acquired T(1)-weighted 3D images of 1204 embryos at a spatial resolution of (40 microm)(3) to (150 microm)(3) in about 2 years. Similarity of image contrast between the T(1)-weighted images and stained anatomical sections indicated that T(1)-weighted 3D images could be used for an anatomical 3D image database for human embryology.  相似文献   
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Morphogenesis in the developing embryo takes place in three dimensions, and in addition, the dimension of time is another important factor in development. Therefore, the presentation of sequential morphological changes occurring in the embryo (4D visualization) is essential for understanding the complex morphogenetic events and the underlying mechanisms. Until recently, 3D visualization of embryonic structures was possible only by reconstruction from serial histological sections, which was tedious and time-consuming. During the past two decades, 3D imaging techniques have made significant advances thanks to the progress in imaging and computer technologies, computer graphics, and other related techniques. Such novel tools have enabled precise visualization of the 3D topology of embryonic structures and to demonstrate spatiotemporal 4D sequences of organogenesis. Here, we describe a project in which staged human embryos are imaged by the magnetic resonance (MR) microscope, and 3D images of embryos and their organs at each developmental stage were reconstructed based on the MR data, with the aid of computer graphics techniques. On the basis of the 3D models of staged human embryos, we constructed a data set of 3D images of human embryos and made movies to illustrate the sequential process of human morphogenesis. Furthermore, a computer-based self-learning program of human embryology is being developed for educational purposes, using the photographs, histological sections, MR images, and 3D models of staged human embryos.  相似文献   
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Combined therapy of stent graft implantation and open surgery is an alternative method for aortic aneurysm. Seven patients with aortic aneurysm [annulo aortic ectasia (AAE) + Marfan syndrome (4), AAE + arch aneurysm + s/o Beh?et disease (1), acute dissected aneurysm (type A) (1), thoracic aortic true aneurysm (1)] were successfully treated by means of elephant trunk method using a stent graft during total arch replacement. There was no complication related to the stent graft during the perioperative period. Postoperative computed tomographic scans were performed 1 and 6 months later. There was no endleak and no migration, and the aortic diameter around the stent graft was not changed in six patients. However, one patient showed thrombus around the stent graft, because of endleak 2 months after the operation. Such patients should therefore have careful long-term follow-up.  相似文献   
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We treated two occupational lung diseases in different situations during military training. The purpose of this study is to investigate the availability of CT scanning for the evaluation of inhalation pulmonary edema. Two soldiers suffered severe lung edema after using a spray for the daily maintenance of their firearms. Four soldiers suffered severe dyspnea after undertaking drills in a narrow zone where numerous smoke bombs had been used. We evaluated these patients from several aspects. CT scans of the chest of spray-induced patients revealed bilateral infiltration predominantly in the upper lung fields. The patients received steroid pulse treatment and gradually recovered. CT scans of the chest of smoke-induced patients revealed bilateral ground-glass attenuation with peripheral lung sparing. The patients gradually recovered with steroid therapy. In accordance with previous studies, CT scans of the chest in our patients demonstrated that the periphery of the lungs remained normal, except in cases of serious injury. When differential diagnosis is required, we consider that CT scans of the chest are particularly useful; CT findings are useful in determining the severity of lung injury as well as the diagnosis of inhalation pulmonary edema.  相似文献   
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The human type II alveolar epithelial cells lost their specific characteristics during cultivation. We examined the ultrastructural and biochemical nature of the human type II cells cultured by two culture systems. To make a physiological alveoli model, the epithelial cells were seeded onto the cell culture insert and allowed contact with the air directly. The cells exposed to the air expressed polarity and immature lamellar bodies in their cytoplasm. Separately, the alveolar epithelial cells were cultured as spheroids to construct the three-dimensional condition. These cells expressed mature morphological characteristics as epithelial cells and lamellar bodies. The expression of the surfactant apoprotein-A (SP-A) and -C (SP-C) mRNA was compared in the cells cultured as a monolayer, the air exposed and the spheroids. SP-A mRNA was detected in all the cultured epithelial cells, but SP-C mRNA, a specific protein for the type II cells, was expressed only in the cells forming spheroids. The expression of uPA, one of the fibrinolytic enzymes, its receptor (uPAR) and its inhibitor-1 (PAI-1) were also examined. The epithelial cells exposed to the air and formed spheroids expressed a larger amount of uPA mRNA than the monolayer, although the amount of uPAR mRNA were comparable in these cells. The amount of PAI-1 mRNA significantly increased when the epithelial cells were exposed to the air. These results indicate that the type II alveolar epithelial cells induced and preserved their specific characteristics by taking the physiological three-dimensional structure, and these characteristics were partially restored by exposure to the air. Those findings suggest that the alveolar epithelial cells should be cultivated in three-dimensional form with contact to the air to regenerate an appropriate alveolar tissue.  相似文献   
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The present study aimed to describe the positional changes of the ocular organs during craniofacial development; moreover, we examined the relationships among the ocular organs and other internal structures. To do this, we traced the positions of the ocular organs in 56 human early fetal samples at different stages of development using high‐resolution magnetic resonance imaging and phase‐contrast X‐ray computed tomography. The eyes were located on the lateral side in the ventral view at Carnegie stage (CS) 16, and then changed their positions medially during development. The eyes remained in the neurocranium until CS17. However, the eyes changed their positions medially and caudally in the viscerocranium after CS18. The positional relationship between the eyes and pituitary gland changed in the lateral view as development progressed. Specifically, they were close to each other at CS17, but moved apart during the later stages of development. These positional changes were also demonstrated quantitatively with morphometric analyses. Based on the present data, the positional changes of the eyes can be categorized into phases, as follows: Phase 1, dramatic positional changes (early fetal period until CS23); and Phase 2, mild positional changes (stabilized; early fetal period after CS23). Notably, all absolute lengths measured in the present study linearly increased as the crown‐rump length increased irrespective of the phase, while features of the measured angles and ratios differentially changed in Phases 1 and 2. The present data may help improve our understanding of both the normal and abnormal development of the ocular organs and craniofacial area. Anat Rec, 300:2107–2114, 2017. © 2017 Wiley Periodicals, Inc.  相似文献   
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Though stenoses of the descending aorta and its branches are seen with congenital anomalies or systemic inflammation, occlusion of the descending aorta is extremely rare. A patient with an occluded hypoplastic descending thoracic aorta required re-operation because of graft failure between the descending thoracic aorta and the infrarenal abdominal aorta. The etiology of the aortic occlusion in this case is unknown, but inflammation, such as Takayasu disease, is speculated.  相似文献   
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To clarify the special instruments and equipment used for minimally invasive cardiac surgery (MICS), we examined the initial experiences with MICS operations with ministernotomy or minithoracotomy at our institution. Fifty adult patients with congenital, valvular, and/or ischemic heart diseases underwent MICS operations, and all surgical procedures were completed without conversion to full sternotomy. The length of the skin incision was about 10 cm or less in all patients. Postoperative recovery was favorable, and the majority of the patients were discharged from the hospital around the end of the second postoperative week. In this series of patients, an oscillating bone saw, lifting type retractor, 2 blade spreader, cannula with a balloon, and right-angled aortic clamp among other items, were very useful for successfully performing various operations with MICS approaches and techniques. The associated results suggest that MICS with ministernotomy or minithoracotomy was feasible using special instruments and equipment and could be encouraged for adult patients with various cardiovascular diseases.  相似文献   
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