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排序方式: 共有456条查询结果,搜索用时 15 毫秒
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M. Ballas A. Madrigal + R. Bontrop M. J. Giphart J. Bodmer + S. F. Goldmann 《Tissue antigens》1989,34(4):223-232
A panel of eleven HLA-DR5 homozygous lymphoblastoid cell lines was investigated for structural heterogeneity on the product level. HLA class II antigens were isolated by immunoprecipitation with different anti-class II monoclonal antibodies and separated by two-dimensional (2-D) gel electrophoresis. As a result, three distinct DRB1, one commonly expressed DRB3, and two distinct DQ gene products could be identified that combined to four different haplotypes associated with HLA-DR5. A hitherto serologically undetected split of HLA-DRw11 was presented by three cell lines. HLA-DRw11 and HLA-DRw12 were found to be related allospecifities that differ only in their DRB1 locus products, but are closely associated with the supertypic DRB3 allele HLA-DRw52b and with HLA-DQw7. The DRB3 alleles HLA-DRw52a and DRw52c were not detected in our cell line panel, indicating that these supertypic determinants are in negative linkage disequilibrium with HLA-DR5. Our data suggest that intra HLA-DR/DQ crossing-over events contribute to the development of the HLA class II polymorphism. Evidence is presented that the T cell defined HLA-D allospecifities are commonly determined by DRB1 and DQ gene products. 相似文献
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Five cases of cervical pregnancy collected over an 8-year period (1971--1978) are analyzed. The incidence of cervical pregnancy at this institution is 1:7040 pregnancies. All cases were diagnosed prior to 12 weeks' gestation, and conservative treatment was instituted in each case. Etiology, criteria, definition, and clinical and pathologic signs are discussed. Several unusual features are emphasized, particularly conservative treatment and the use of ultrasound as a diagnostic aid. 相似文献
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Ballas LK Elkin EB Schrag D Minsky BD Bach PB 《International journal of radiation oncology, biology, physics》2006,66(4):1204-1211
PURPOSE: About half of all cancer patients in the United States receive radiation therapy as a part of their cancer treatment. Little is known, however, about the facilities that currently deliver external beam radiation. Our goal was to construct a comprehensive database of all radiation therapy facilities in the United States that can be used for future health services research in radiation oncology. METHODS AND MATERIALS: From each state's health department we obtained a list of all facilities that have a linear accelerator or provide radiation therapy. We merged these state lists with information from the American Hospital Association (AHA), as well as 2 organizations that audit the accuracy of radiation machines: the Radiologic Physics Center (RPC) and the Radiation Dosimetry Services (RDS). The comprehensive database included all unique facilities listed in 1 or more of the 4 sources. RESULTS: We identified 2,246 radiation therapy facilities operating in the United States as of 2004-2005. Of these, 448 (20%) facilities were identified through state health department records alone and were not listed in any other data source. CONCLUSIONS: Determining the location of the 2,246 radiation facilities in the United States is a first step in providing important information to radiation oncologists and policymakers concerned with access to radiation therapy services, the distribution of health care resources, and the quality of cancer care. 相似文献
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Marakis G Pavlidis TE Ballas K Karvounaris D Rafailidis S Sakantamis AK 《Journal of laparoendoscopic & advanced surgical techniques. Part A》2006,16(6):582-586
BACKGROUND: The influence of laparoscopic cholecystectomy on coagulation and fibrinolysis is debatable. There have been a few but controversial studies and the need for routine antithrombotic prophylaxis is unclear. MATERIALS AND METHODS: In this prospective study we investigated changes in coagulation and fibrinolysis parameters in laparoscopic cholecystectomy. Blood samples taken before, during, and after surgery from 38 consecutive patients were analyzed. Measured parameters included the international normalized ratio, prothrombin time, partial thromboplastin time, antithrombin III activity, platelet count, mean platelet volume, fibrinogen, and D-dimers. RESULTS: Statistically significant changes included increased perioperative international normalized ratio and D-dimers, and postoperative antithrombin III, fibrinogen, and D-dimers, as well as decreased perioperative antithrombin III and fibrinogen and postoperative international normalized ratio, platelet count, and mean platelet volume. Values of partial thromboplastin time had no statistically significant changes. CONCLUSION: Reduced coagulation activity and increased fibrinolytic activity occur during and after laparoscopic cholecystectomy. 相似文献
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C Dimopoulos M Scouteris B Hatziconstantinou L Polyzos P Ballas G Daicos 《European urology》1975,1(3):145-150
Ten cases of pheochromocytomae, of which eight were benign and two malignant have been considered. All patients presented with hypertension, either paroxysmal (7 cases) or permanent (3 cases). It is essential to emphasize that the initial symptomatology of these patients on their admission to the hospital was often atypical and misleading: in 2 cases, the symptomatology was urological, in 2 cases psychatric and in one digestive. Quantitative determination of catecholamines and their metabolites was positive in 7 cases out of 10. Retropneumoperitoneal insufflation combined with intravenous urography and tomographies provided valuable information in each case. The surgical removal of these tumours, which was unilateral and in normal position, in each case, was carried out without complications. Sudden blood pressure variations observed during the operation could be controlled without difficulty. In 6 patients, the blood pressure became normal and remained so for 4 years. In 2 other patients, the blood pressure came back to normal after the operation, but presented a slight increase 1 year later. Pheochromocytomae, which are often masked by a misleading symptomatology, must be systematically searched for in all hypertensive patients, despite the characteristics of the hypertension. Surgical removal, if done early enough, produces cure of the hypertension. 相似文献