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1.
Yoshie Ochiai Kazuhiro Kurisu Takashi Kajiwara Hiroshi Kumeda Ryuji Tominaga 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2004,52(2):81-83
We describe a case of type B aortic dissection with large ascending aortic aneurysm occurring 12.8 years after aortic root
replacement (Cabrol procedure) in a non-Marfan patient with cystic medial necrosis of the aorta. We have successfully performed
an extended total aortic arch replacement using a four-branched graft through the “L-indsion” approach (a combination of a
left anterior thoracotomy and upper half median sternotomy). Of note, a histological specimen from the aneurysmal ascending
aortic wall revealed “healed aortic dissection” with fibrous tissue replacing the media and intima in addition to multiple
foci of cystic medial necrosis. 相似文献
2.
目的 探讨在“2× 4”矫治技术中弓丝弯制的方法及原理。方法 替牙牙合时期前牙反牙合患者 2 4例 ,使用粗弓丝 ,在其弓丝上弯制各种曲形 ,并根据不同错牙合类型 ,处理各种曲与牙齿、带环关系 ,防止出现磨牙旋转移动等异常。结果 2~ 6个月纠正反牙合 ,2 4例替牙牙合时期反牙合患者得以早期矫治。结论 本方法矫治时间短 ,效果明显 ,操作简单 ,能够达到较为理想的矫治效果 相似文献
3.
Leon A. Weisberg Jack Greenberg Antonio Stazio 《Computerized medical imaging and graphics》1988,12(6):379-383
The clinical and computerized tomographic (CT) findings in 10 patients with cerebral toxoplasmosis are reviewed. All patients with cerebral toxoplasmosis were homosexuals and/or intravenous drug users, and all patients had other manifestations of AIDS. Two presented with focal seizures, 4 presented with focal neurological deficit which progressively worsened, and 4 had evidence of diffuse neurological dysfunction (altered consciousness, generalized seizures). CT showed a single lesion in 3 patients and multiple lesions in 7 patients. Two patients had hypodense nonenhancing lesions(s). Eight patients had hypodense lesions with peripheral or nodular enhancement. The lesions were more commonly located in the cerebral hemispheres and subcortical gray matter nuclear masses (thalamus, basal ganglia). The finding of a hypodense lesion with a central slightly hyperdense noncalcified region that showed dense nodular homogeneous enhancement was quite characteristic of cerebral toxoplasmosis, but this pattern may also be seen in other neurological conditions including brain lymphomas. 相似文献
4.
MRI demonstration and CT correlation of the brain in patients with idiopathic intracerebral calcification 总被引:2,自引:0,他引:2
Twenty-two patients aged 36–63 years were diagnosed as having Fahr's syndrome on the basis of the presence on CT of unexpected extensive calcification of the basal ganglia. Even when associated with calcification of other brain areas, the main diagnostic criterion remained basal ganglia calcification larger than 800 mm2. Normal values of parathormone, serum calcium and phosphorus excluded hypercalcaemia and hypoparathyroidism. Mitochondrial CNS disease was excluded clinically. MRI and repeated CT and neurological examination were performed in all of the patients. The patients were divided into two groups: neurologically asymptomatic (group 1) and neurologically symptomatic (group 2). T2-weighted sequences demonstrated hyperintense areas in all of the patients involving the white and the grey matter of the brain. In group 1 the hyperintense lesions were significantly smaller than in group 2. The neurological symptoms correlated better with the hyperintensities on T2-weighted MR images than with the calcification demonstrated on CT. Hyperintensities in T2-weighted MRI and the areas shown by CT to have calcification had different locations. In 15 patients with dementia, the white matter of the entire centrum semiovale was bilaterally hyperintense. In another 3 patients with hemiparesis, hyperintense areas in the internal capsule, contralateral to the side of hemiparesis, were demonstrated in the T2-weighted sequence. The hyperintense T2 signals may reflect a slowly progressive, metabolic or inflammatory process in the brain which subsequently calcifies and are probably responsible for the neurological deficit observed. 相似文献
5.
C. Bosman E. Bonucci P. Gugliantini L. Saguí 《Virchows Archiv : an international journal of pathology》1977,373(1):23-35
Summary An ultrastructural study of chondrodystrophia calcificans congenita is reported. Foci of initial calcification of cartilage are characterized by coexistence of three different types of crystals, probably due to abnormal proteoglycan composition of cartilage matrix. The calcification process in chondrodystrophia calcificans congenita is apparently not related to matrix vesicles as it is in normal cartilage. 相似文献
6.
The structure of hard tissue areas (with osteoid and calcified matrix) in 10 osteoblastic, chondroblastic, and fibroblastic osteogenic sarcomas was studied in the electron microscope. Neoplastic cells commonly associated with these areas and presumably actively involved in the production of hard tissue were osteo-blastlike cells types 1 and 3, chondroblastlike cells type 1, and fibroblastlike cells, as defined and characterized in previous studies. The cells differed from those in soft tissue areas of osteogenic sarcomas in but one respect: they usually showed presence of irregular extrusions at their surfaces. Other types of osteoblastlike and chondroblastlike cells occurred rarely or not at all. Two types of multinucleated giant cells were recognized in these areas, one showing a fine structure reminiscent of that in osteoclasts, the other probably being of a neoplastic nature and engaged in the production of the calcifying matrix. The evidence suggested that neoplastic osteoblastlike, chondroblastlike, and fibrolastlike cells as well as certain multincleated giant cells might all be involved in the mineralization process and/or the formation of osteoid in osteogenic sarcomas. Although phenotypically of highly variable appearance, all these different cells may thus functionally (and probably histogenetically) be closely related.
The mineralization process in the tumor tissue appeared to be a modification of what occurs in normal ossification, possibly with an alternative or complementary pathway involving the production of spherical bodies with layered contents. 相似文献
The mineralization process in the tumor tissue appeared to be a modification of what occurs in normal ossification, possibly with an alternative or complementary pathway involving the production of spherical bodies with layered contents. 相似文献
7.
许铁华 《中国临床解剖学杂志》1988,(2)
本文测量了58具成年尸体食管胸段的长度,用内外相关和自身比例的方法,着重对食管胸段前邻器官的占位及其在胸骨上的投影作了定位研究,并结合临床应用进行了讨论。 相似文献
8.
Paolo Masiello Generoso Mastrogiovanni Pierpaolo Chivasso Donato Triggiani Francesco Cafarelli Severino Iesu 《Journal of cardiac surgery》2021,36(1):371-373
Reimplantation of the supra‐aortic vessels can be challenging with Thoraflex Hybrid. A device modification made the vessel lengths more appropriate and the position of the neo‐vessels in the chest avoided malpositioning and kinking and facilitated sternum closure; this may improve operating times as well as allowing complete and continuous cerebral trivascular perfusion and corrects positioning of the intrathoracic vessels. 相似文献
9.
Adenohypophyses of human newborns contain characteristic psammoma bodies. Their numbers are maximal within 2 weeks of the
neonatal period and diminish thereafter. They are very rare in infant pituitaries, seeming to disappear by shrinkage in that
there is a significant direct correlation between their number and size. The bodies were found to contain a high concentration
of endogenous peroxidase, thus suggesting that the enzyme may be responsible for their disappearance. A statistical majority
of psammoma bodies were located within follicular lumens. By immunohistochemistry, the follicular epithelium surrounding psammoma
bodies showed immunoreactivity for various pituitary hormones. Light microscopy demonstrated that adenohypophysial cells surrounding
psammoma bodies contain randomly, scattered granules or globules exhibiting peroxidase activity. Extrusion of such granules
into follicular lumens may play a role in the genesis of the concretions. The conspicuous lamellar nature of the calcified
psammoma bodies suggests that waves of calcium deposition occur during their morphogenesis. Despite histologic similarities,
the histochemical characteristics of this type of psammoma body differ from those in other organs as well as from the calcification
encountered in prolactin (PRL)-producing pituitary adenomas. 相似文献
10.
Tetsuo Hadama Yoshiaki Mori Osamu Shigemitsu Tatsunori Kimura Shinji Miyamoto Hidenori Sako Tooru Soeda Toshihide Yoshimatsu Yuzo Uchida 《Surgery today》1996,26(1):60-63
We report herein the rare case of a 79-year-old man who suffered permanent paraplegia after undergoing an otherwise successful total arch replacement for a ruptured aortic arch aneurysm. During cardiopulmonary bypass, perfusion to the distal aorta was maintained from the femoral artery, and postoperative aortography showed intact tributaries from the aorta including the intercostal arteries. Postoperative paraplegia is an extremely rare complication of operations on the aortic arch; however, we speculate that the paraplegia in this patient could be attributed either to a steal phenomenon involving the radicular artery, or to the anatomical particularity of the spinal cord artery described by Cole and Gutelius as the segmental system. 相似文献