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排序方式: 共有2505条查询结果,搜索用时 15 毫秒
51.
Sakamoto K Kase M Mo M Kurata H 《Kyobu geka. The Japanese journal of thoracic surgery》2000,53(1):74-77
Mature teratomas occasionally rupture into adjacent organs such as lung, bronchus, mediastinum and pericardial sac. However, perforation into the pericardial sac is rare. We experienced a case of mediastinal mature teratoma perforated into the pericardial sac. A 16-year-old man was admitted to our hospital due to sudden severe anterior chest pain. Chest X-ray showed a mass shadow in the right middle lung field. Chest CT scan and MRI demonstrated a heterogeneous mass with fat component in the right anterior mediastium adjacent to the pericardium. Some squamous cells were obtained from the mass by CT guided percutaneous needle biopsy. Operation was performed with the diagnosis of mediastinal teratoma. The mass adhered to the pericardium and turbid pericardial effusion was noted. The mass was removed with the pericardium. The mass was 9 x 6.5 x 6 cm in size, which contained yellow sebaceous material and a tuft of white hair. The pathological diagnosis of the mass was mature cystic teratoma with perforation into the pericardial sac. 相似文献
52.
Chemotherapyremainsoneofthemosteffectivetreatmentsfordisseminatedneoplasia[1 ] .However,theef ficacyofmanychemotherapeuticagentsislimitedbytheirtoxicitytonormaltissues,resultinginanarrowtherapeuticindex.Myelosuppressionisthemostfrequentacutedose limitingsideeffectresponsiblefordelaysindrugadminis trationordoseattenuationwithdecreasedantitumorre sponse[2 4] .Particularly,thrombocytopeniaremainsasig nificantcauseofmorbidityincancerpatientsundergoingallogenicorautologousbonemarrow/bloodstemcellt… 相似文献
53.
Kurata C Uehara A Sugi T Ishikawa A Fujita K Yonemura K Hishida A Ishikawa K Tawarahara K Shouda S Mikami T 《Nephron》2000,84(4):312-319
To characterize uremic cardiac autonomic neuropathy, we measured plasma catecholamines, analyzed the 24-hour heart rate variability (HRV), and acquired serial images with (123)I-metaiodobenzylguanidine (MIBG) in 44 patients with chronic renal failure on hemodialysis and in 14 controls. Time-domain measures were calculated using the Marquette HRV program. MIBG clearance rates from the heart and lung were evaluated on planar images, and the regional MIBG uptake in the left ventricular myocardium was evaluated with single-photon emission computed tomography. Compared with controls, plasma dopamine and norepinephrine levels were elevated (p < 0.001 and p = 0.03, respectively), and all the time-domain measures of HRV were reduced in the patients (p < 0.001). The MIBG clearance rate from the heart was higher (p < 0.001), that from the lung was lower (p < 0.001), and the myocardial MIBG distribution was more heterogeneous in patients than in controls (total uptake score p = 0.03). These variables were similar between 26 patients without and 18 patients with hypertension. Uremic cardiac autonomic neuropathy may be characterized by high plasma levels of dopamine and norepinephrine, reduced HRV, and abnormal MIBG kinetics in the heart with heterogeneous myocardial MIBG distribution, suggesting cardiac sympathetic overactivity and parasympathetic deterioration. In addition, abnormal MIBG kinetics in the lung may imply pulmonary sympathetic nervous dysfunction and/or endothelial dysfunction in uremic patients. 相似文献
54.
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56.
Yoshiyuki Kurata Machiko Oshida Hironori Take Takayasu Furubayashi Hirohisa Nakao Yoshiaki Tomiyama Yoshio Kanayama Nobuo Nagao Yasuto Okubo Takeshi Yonezawa and Seiichiro Tarui 《Vox sanguinis》1989,57(3):199-204
A new method was studied for eliminating HLA class I antigens from the surface of platelets without damaging the cells. Platelets were exposed to an acid solution (pH 3.0) to eliminate the antigenicity of HLA class I antigens. The reduction in antigenicities of HLA class I common antigen and individual HLA class I antigens by acid treatment was marked. Patients' sera which contained multispecific HLA antibodies reacted with PBS-treated platelets, but not with acid-treated platelets. No changes were observed in the antigenicities of glycoprotein Ib or glycoprotein IIb/IIIa. The viability of acid-treated platelets was 83%. Ultrastructural investigations revealed no significant difference between the PBS-treated platelets and acid-treated platelets. The platelet function studies showed that the aggregation of acid-treated platelets induced by various agonists was only slightly reduced compared with PBS-treated platelets. We propose that acid-treated platelets are promising for clinical use in patients refractory to platelet transfusions and may be superior to chloroquine-treated platelets for analysis of the specificity of antiplatelet antibodies. 相似文献
57.
Expression of GPIV and Naka antigen on monocytes in Naka -negative subjects whose platelets lack GPIV
Hironori Take Hirokazu Kashiwagi Yoshiaki Tomiyama Shigenori Honda Yumiko Honda Hajime Mizutani Takayasu Furubayashi Takahiro Karasuno Tetsuo Nishiura Yoshio Kanayama Yoshiyuki Kurata Yuji Matsuzawa 《British journal of haematology》1993,84(3):387-391
Summary. The platelet antigen Naka was once considered to be a platelet-specific alloantigen and is carried on platelet membrane glycoprotein (GP) IV. Recent studies suggest that Naka -negative subjects lack platelet GPIV. GPIV is an important adhesive receptor and expressed on the surface of monocytes as well as of platelets. In the present study, flow cytometry was used to detect GPIV and Naka antigen on the surface of monocytes. Naka antigen was expressed on monocytes as well as on platelets in Naka -positive subjects ( n = 6) (P-GPIV-positive subjects). To our surprise, monocytes of Naka -negative subjects ( n = 7) (P-GPIV-negative subjects) having no anti-Naka antibody in their serum expressed GPIV and Naka antigen to almost the same degree as did the monocytes of P-GPIV-positive subjects. Competitive experiments using OKM5 (a monoclonal antibody against GPIV) and anti-Naka antibody showed that the epitope of anti-Naka antibody on monocytes was very close to that of OKM5. In two P-GPIV-negative subjects having anti-Naka antibody in their serum, GPIV and Naka antigen were not expressed on the surface of either monocytes or platelets. These results indicate that the GPIV molecules and Naka antigen are expressed on the surface of monocytes in the majority of P-GPIV-negative subjects, but that in a very few P-GPIV-negative subjects neither GPIV nor Naka antigen is expressed on the surface of their monocytes. We hypothesize that P-GPIV-negative subjects who carry neither GPIV nor Naka antigen on their monocytes produce anti-Naka antibody as a result of transfusion or pregnancy. 相似文献
58.
El-Samad H Kurata H Doyle JC Gross CA Khammash M 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(8):2736-2741
Molecular biology studies the cause-and-effect relationships among microscopic processes initiated by individual molecules within a cell and observes their macroscopic phenotypic effects on cells and organisms. These studies provide a wealth of information about the underlying networks and pathways responsible for the basic functionality and robustness of biological systems. At the same time, these studies create exciting opportunities for the development of quantitative and predictive models that connect the mechanism to its phenotype then examine various modular structures and the range of their dynamical behavior. The use of such models enables a deeper understanding of the design principles underlying biological organization and makes their reverse engineering and manipulation both possible and tractable The heat shock response presents an interesting mechanism where such an endeavor is possible. Using a model of heat shock, we extract the design motifs in the system and justify their existence in terms of various performance objectives. We also offer a modular decomposition that parallels that of traditional engineering control architectures. 相似文献
59.
Akira Kurata Teruhito Mochizuki Yasushi Koyama Toyoaki Haraikawa Jun Suzuki Yuji Shigematsu Jitsuo Higaki 《Circulation journal》2005,69(5):550-557
BACKGROUND: The present study was designed to: (i) detect myocardial ischemia in contrast enhanced multi-slice spiral computed tomography (CE-MSCT) using adenosine triphosphate (ATP) pharmacological stress test; and (ii) evaluate the potential of ATP stress CE-MSCT in a clinical setting. METHODS AND RESULTS: Twelve patients underwent ATP stress CE-MSCT and stress thallium-201 myocardial perfusion scintigraphy (MPS) and 9 of the patients received conventional coronary angiography (CAG). Dual CE-MSCT scans were performed for stress and rest images, with and without intravenous infusion of ATP (0.16 mg.kg-1.min-1) at intervals of 20 min. Myocardial perfusion and coronary artery were visually evaluated using MSCT and compared the results obtained from MPS and CAG. Of 36 territories, stress images of CE-MSCT described 26 hypo-perfusion areas and MPS described 22 redistributions. The agreement between MSCT and MPS was 83% (30/36, p<0.05). In 141 coronary artery segments of 9 patients undergoing CAG, rest images of CE-MSCT, which had significantly higher assessability than stress images (89% vs 48%, p<0.05), described 76% (13/17) of culprit coronary stenoses. CONCLUSIONS: Although CT-angiography should be currently assessed using rest images, ATP stress CE-MSCT can describe both ATP-induced myocardial ischemia and coronary artery stenoses in patients with coronary artery disease. 相似文献
60.
Highly variable sequences in the env V3 region of HIV type 1 distributing among Thai carriers from 1995 to 1997 总被引:2,自引:0,他引:2
Auwanit W Ayuthaya PI Duangchanda S Mukai T Kurata T Ikuta K 《AIDS research and human retroviruses》2000,16(3):283-289
The amino acid sequences of the Env V3 region of HIV-1 subtype E in Thailand were highly variable in the samples obtained from 1995 to 1997, compared with the previously reported sequences in samples obtained from 1990 to 1993. The sequences of the V3 region in the samples from five provinces in Thailand revealed that the variability was much higher in the samples from Bangkok and Ubonrachathani than in those from Chiangmai, Prathumthani, and Trang. There was no apparently different level of diversity at the V3 region in the samples from symptomatic and asymptomatic individuals. The V3 loop motif in most (66.7%) of the samples was GPGQ, although this motif was more heterogeneous in the samples from Bangkok and Ubonrachathani than in those from the other three provinces. The N-linked glycosylation sites in the V3 region among these samples were relatively conserved. There was no apparent difference in the presence of positively charged amino acids at positions 306 and 320 between the samples from symptomatic and asymptomatic individuals. 相似文献