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We describe an infertile man with normal secondary sexual characteristics and a 45X karyotype. Physical examination showed bilateral soft small testes and the semen contained no sperm. Serum testosterone, estrogen and gonadotropin levels were within normal range. Biopsy of the testis showed germinal aplasia. 相似文献
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Somites are formed by periodic segmentation of the presomitic mesoderm (PSM). This periodic event is controlled by the segmentation clock, where Notch signaling plays an essential role. The basic helix-loop-helix factor Hes7, a Notch effector, is cyclically expressed by negative feedback and regulates cyclic expression of Lunatic fringe (Lfng), a Notch modulator. Lfng then seems to periodically inhibit Notch, leading to oscillation in Notch activity. It is thought that these coupled negative feedback loops by Hes7 and Lfng are important for sustained and synchronized oscillations in the PSM. Of interest, another Notch effector, Hes1, is cyclically expressed by many cell types such as neuroblasts, suggesting that this clock is widely distributed and regulates many biological events. This review summarizes the recent finding about roles and mechanism of Notch signaling in the segmentation clock and discusses the significance of Hes1 oscillation in non-PSM cells. 相似文献
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Yoshito Tomimaru Ken Kodama Jiro Okami Kazuyuki Oda Koji Takami Masahiko Higashiyama 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2006,54(5):193-198
Objective Postoperative pericardial effusion commonly occurs after open heart surgery. However, after general thoracotomy such as pulmonary
resection, there have been few reports of pericardial effusion. The purpose of this study is to investigate patients with
pericardial effusion following pulmonary resection.Methods: Among 2,385 patients with pulmonary resection for lung neoplasm in our institute, eight patients, whose pericardium had
never been opened during the operation, developed pericardial effusion. The clinical characteristics of the eight patients
were analyzed.Results: Pericardial effusion after pulmonary resection was divided into two subtypes: pericardial effusion in three patients with
left thoracotomy occurring within 30 days postoperatively, and pericardial effusion in the remaining five patients with right
thoracotomy occurring more than 30 days postoperatively. Pericardiotomy or pericardiocentesis was performed in three symptomatic
patients, and the remaining five asymptomatic patients were treated with diuretics. Pericardial effusion disappeared in three
of the five patients about 1–3 months after the conservative treatment, while, in the remaining patients, because pericardial
effusion had increased gradually, pericardiocentesis was performed.Conclusion: From our experience, the treatment strategy of drainage for early pericardial effusion and diuretics for late pericardial
effusion seems to be appropriate. (Jpn J Thorac Cardiovasc Surg 2006; 54:193-198) 相似文献
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Yoshito Sadahira Masaharu Mori Michitaka Ozaki Michiyasu Awai 《Pathology international》1987,37(11):1719-1729
The so-called Potter's lesion, previously described as preneoplastic in the lymph nodes of C58 mice, develops frequently in autoimmune NZB mice. These lesions were characterized in the present study by bands or sheets of palestaining histiocytic cells in the cortex and medulla of the lymph node, and multiple small nodules of the same cells were found in the red pulp of the spleen and the liver. Electron microscopically, the cells had pleomorphic cytoplasm with long processes, electron-dense bodies, abundant mitochondria, and a characteristic labyrinth structure with many C-type viruses. Mac-1 antigen, IgG-Fc receptor, ferritin, and ACPase activity were identified on these cells. Intraperitoneally-injected iron colloids were found in the lesions of the spleen and liver but not in those of the lymph nodes. The lymph node lesions appeared when the mice were about 3 months of age and enlarged until the mice were around 10 months old, after which they gradually receded and were replaced by small vessels and fibroblastic cells. These data indicate that the lesions represent reactive hyperplasia of the macrophage system and may have no direct association with the development of malignant lymphoma in NZB mice. 相似文献
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Y. Suzuki S. Ehara H. Shiraishi J. Nishida G. Murooka Y. Tamakawa 《Skeletal radiology》1997,26(2):128-130
The case of a 14-year-old girl with rhabdomyosarcoma of the right foot is reported. Plain radiography showed a large nonspecific
soft tissue tumor between the metatarsals with bowing of the metatarsals away from the mass. MR imaging showed a large soft
tissue mass involving the metatarsals. The findings were conflicting, because the tumor had an infiltrative soft tissue mass
and bowing of the metatarsals more suggestive of slow expansive growth. Bowing of short tubular bones may be a process similar
to cortical saucerization, which is typically seen in Ewing’s sarcoma, and it can be one of the findings of high grade neoplasms,
such as embryonal rhabdomyosarcoma. 相似文献