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排序方式: 共有6137条查询结果,搜索用时 15 毫秒
991.
TM Karsten JH Allema M Reinders TM van Gulik LT de Wit PC Verbeek K Huibregtse GN Tytgat DJ Gouma 《Canadian Metallurgical Quarterly》1996,162(11):881-888
OBJECTIVE: To analyse the outcome of preoperative biliary drainage in patients being operated on for a tumour in the pancreatic head. DESIGN: Retrospective study. SETTING: University hospital, The Netherlands. SUBJECTS: Consecutive series of 241 patients. MAIN OUTCOME MEASURES: Decline in bilirubin concentrations and bacterial contamination of bile as a result of preoperative drainage. Incidence of postoperative complications in patients who underwent preoperative drainage and those who did not. RESULTS: 184/241 patients underwent preoperative biliary drainage. Endoscopic drainage was the most effective, shown by a median reduction in bilirubin concentrations of 82%, 74%, and 50% after endoscopic drainage (n = 149), papillotomy (n = 25) and external drainage (n = 10), respectively. Bacterial contamination of bile was significantly more common when an endoprosthesis was used, but did not result in a higher rate of infective complications. 163 Whipple's resections, 33 total pancreatectomies, and 45 biliary-enteric bypasses were performed. 137/241 (57%) patients had postoperative complications. There was no significant difference in the incidence of postoperative complications between patients who had preoperative biliary drainage and those who did not (p = 0.4). 相似文献
992.
DJ As D Schikora A Greiner M Lübbers J Mimkes K Lischka 《Canadian Metallurgical Quarterly》1996,54(16):R11118-R11121
993.
Bone metastases from colorectal cancer are uncommon and usually present late in the natural history of metastatic disease. This case report describes a 48-year-old man who developed an unusual distribution of bony metastases with multifocal osteolytic tarsal metastases 50 months after excision of a rectal carcinoma. An open biopsy was required to establish the diagnosis, exclude osteomyelitis and allow palliative radiotherapy to be given. 相似文献
994.
BD Sidell ME Vayda DJ Small TJ Moylan RL Londraville ML Yuan KJ Rodnick ZA Eppley L Costello 《Canadian Metallurgical Quarterly》1997,94(7):3420-3424
The important intracellular oxygen-binding protein, myoglobin (Mb), is thought to be absent from oxidative muscle tissues of the family of hemoglobinless Antarctic icefishes, Channichthyidae. Within this family of fishes, which is endemic to the Southern Ocean surrounding Antarctica, there exist 15 known species and 11 genera. To date, we have examined eight species of icefish (representing seven genera) using immunoblot analyses. Results indicate that Mb is present in heart ventricles from five of these species of icefish. Mb is absent from heart auricle and oxidative skeletal muscle of all species. We have identified a 0.9-kb mRNA in Mb-expressing species that hybridizes with a Mb cDNA probe from the closely related red-blooded Antarctic nototheniid fish, Notothenia coriiceps. In confirmation that the 0.9-kb mRNA encodes Mb, we report the full-length Mb cDNA sequence of the ocellated icefish, Chionodraco rastrospinosus. Of the eight icefish species examined, three lack Mb polypeptide in heart ventricle, although one of these expresses the Mb mRNA. All species of icefish retain the Mb gene in their genomic DNA. Based on phylogeny of the icefishes, loss of Mb expression has occurred independently at least three times and by at least two distinct molecular mechanisms during speciation of the family. 相似文献
995.
SW Hughes TJ D'Arcy DJ Maxwell W Chiu A Milner JE Saunders RJ Sheppard 《Canadian Metallurgical Quarterly》1996,22(5):561-572
A system is described for calculating volume from a sequence of multiplanar 2D ultrasound images. Ultrasound images are captured using a video digitising card (Hauppauge Win/TV card) installed in a personal computer, and regions of interest transformed into 3D space using position and orientation data obtained from an electromagnetic device (Polhemus, Fastrak). The accuracy of the system was assessed by scanning 10 water filled balloons (13-141 mL), 10 kidneys (147-200 mL) and 16 fetal livers (8-37 mL) in water using an Acuson 128XP/10 (5 MHz curvilinear probe). Volume was calculated using the ellipsoid, planimetry, tetrahedral and ray tracing methods and compared with the actual volume measured by weighing (balloons) and water displacement (kidneys and livers). The mean percentage error for the ray tracing method was 0.9 +/- 2.4%, 2.7 +/- 2.3%, 6.6 +/- 5.4% for balloons, kidneys and livers, respectively. So far the system has been used clinically to scan fetal livers and lungs, neonate brain ventricles and adult prostate glands. 相似文献
996.
997.
998.
B Yung IA Campbell JS Elborn JS Harvey DJ Shale 《Canadian Metallurgical Quarterly》1996,90(6):353-356
Between September 1987 and April 1995, 33 totally implantable venous access devices (TIVADs) were implanted at the Cardiff Adult Cystic Fibrosis Centre, U.K., for the purpose of intermittent antibiotic therapy, including 22 PORT-A-CATH (Simcare Ltd.) devices (PCs) to 18 patients, and 11 P.A.S.PORT (Simcare Ltd.) devices (PPs) to nine patients. There were 50 complications during 25 824 days of catheter function which were severe enough to lead to removal of the devices in eight patients (six PCs and four PPs). Overall, patients' acceptance of these devices was excellent. Despite a shorter functional time and a higher rate of complications in PPs compared with PCs, PPs were preferred by many patients for cosmetic reasons. Totally implantable venous access devices provide safe, effective and convenient means of venous access in cystic fibrosis patients requiring intermittent antibiotic therapy. 相似文献
999.
We have solved the solution structure of the aminoglycoside antibiotic tobramycin complexed with a stem-loop RNA aptamer. The 14 base loop of the RNA aptamer 'zippers up' alongside the attached stem through alignment of four mismatches and one Watson-Crick pair on complex formation. The tobramycin inserts into the deep groove centered about the mismatch pairs and is partially encapsulated between its floor and a looped out guanine base that flaps over the bound antibiotic. Several potential intermolecular hydrogen bonds between the charged NH3 groups of tobramycin and acceptor atoms on base pair edges and backbone phosphates anchor the aminoglycoside antibiotic within its sequence/structure specific RNA binding pocket. 相似文献
1000.
JA Bartlett DJ Sexton 《Canadian Metallurgical Quarterly》1998,33(12):53-6, 61-4, 67-9; discussion 69-71
Four cases illustrate some of the issues involved in treating HIV-infected patients in a primary care setting. Primary care physicians are hard-pressed to achieve the same results as infectious disease specialists, yet are increasingly responsible for performing the initial tests, choosing the therapeutic regimen, ensuring the patient's compliance with the regimen, and monitoring the results. 相似文献