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1.
A retrospective study was done in 316 patients with primary cervical adenocarcinoma treated at the Research Institute for Clinical and Experimental Oncology in Brno over a period of 40 years (1939-1978). The treatment results were compared to those in 2571 patients with epidermoid carcinomas of the uterine cervix treated at the Institute over the same period. The 5-year survival rate was significantly lower in adenocarcinoma patients (in Stage I patients, 77.8% vs. 84.5%, and, in the whole group, 60.8% vs. 70.3%). The assessment of the treatment results of this study has clearly showed that in cervical adenocarcinomas, surgery combined with radiotherapy was much more effective than radical radiotherapy alone (77.4% vs. 64.7%). In contrast to this, in epidermoid carcinomas the treatment results were better after radical radiotherapy (86.5% vs. 81.3%). Thus, in the prognosis of cervical adenocarcinomas the mass of the tumor, the size of the uterus, as well as the grading play a role. That means that primary cervical adenocarcinomas at early stages can be successfully treated by a combination of radical surgery and radiotherapy, while radiotherapy of advanced stages of this tumor is less successful. 相似文献
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In an effort to identify the pathway leading to the formation of 1-beta-D-arabinofuranosylcytosine-diphosphate (ara-CDP)-choline from 1-beta-D-arabinofuranosylcytosine (ara-C) treatment of cultured cells, as well as of cells obtained from leukemia patients, we probed the enzymatic steps involved in the CDP-choline pathway for phosphatidylcholine biosynthesis. Ara-C-triphosphate was not a substrate for CTP:phosphocholine cytidylyltransferase activity under the conditions employed, whereas CTP and dCTP were utilized to form CDP-choline and dCDP-choline, respectively. When presented together, ara-C-triphosphate and CTP inhibited the enzymatic conversion of CTP to CDP-choline in the presence of phosphocholine, with a Ki of 6 mM. Since CTP:phosphocholine cytidylyltransferase did not appear to be responsible for the increased levels of ara-CDP-choline, we next studied the other enzyme in the pathway for phosphatidylcholine synthesis that could form ara-CDP-choline, CDP-choline:1,2-diacylglycerol cholinephosphotransferase. CDP-choline:1,2-diacylglycerol cholinephosphotransferase activity present in microsomes isolated from L5178Y murine leukemia cells exhibited a reversal of its normal catalytic activity, using CMP and 1-beta-D-arabinofuranosylcytosine-monophosphate (ara-CMP) along with phosphatidylcholine to produce either CDP-choline or ara-CDP-choline, plus diradylglycerol. The Vmax and Km values for CMP were 0.78 +/- 0.04 nmol/min/mg and 340 +/- 20 microM, respectively, whereas the Vmax and Km for ara-CMP were 0.22 +/- 0.06 nmol/min/mg and 1410 +/- 540 microM, respectively. A Ki value of 3 mM was obtained for ara-CMP under the cell-free assay conditions used. These results indicate that ara-CDP-choline most likely arises from a reversal of the CDP-choline:1,2-diacylglycerol cholinephosphotransferase utilizing ara-CMP, rather than from the catalysis of ara-C-triphosphate plus phosphocholine to ara-CDP-choline by CTP:phosphocholine cytidylyltransferase. It is speculated that this mechanism may explain, in part, the rapid cellular lysis observed with high dose ara-C therapy. 相似文献
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The advantages of the new, safer, but more expensive iodinated contrast agents are discussed, and opinions on which patient groups should receive the agents are presented. 相似文献
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J Snajdauf M Rygl J Kalousová A Kucera O Petr? K Pycha V Mixa R Keil Z Hríbal 《Zeitschrift für Kinderchirurgie》2007,17(5):317-321
INTRODUCTION: Major or complicated pancreatic trauma in children is uncommon and management strategies remain controversial. The aim of this study was to evaluate our experience with both early and delayed surgery in these pediatric cases. METHODS: We carried out a retrospective analysis of data of pediatric patients with major or complicated pancreatic injury operated on between January 1994 and December 2005 in our pediatric trauma center. RESULTS: Thirteen children (9 boys and 4 girls) with a mean age of 8.5 years (range 3 - 16 years) were operated for major or complicated pancreatic injury. The extent of injury was: grade II (major contusion without duct injury or tissue loss) in 4 children; grade III (distal transection) in 5 children and grade IV injury (proximal transection) in four patients. Pseudocyst developed in 8 children: 4 with grade II injury, 2 with grade III injury and 2 with grade IV injury (one with abdominal pseudocyst and one with an abdominal and a mediastinal pseudocyst). Early diagnosis and operation was achieved in 5 cases, while delayed diagnosis and operation occurred in 8. Three children underwent cystogastrostomy; 6 had a spleen-sparing distal pancreatectomy and 4 had resection with Roux-en-Y jejunostomy drainage. Endoscopic retrograde cholangiopancreaticography (ERCP) was the most useful diagnostic tool in assessing ductal injury. There were no deaths or long-term morbidity in our group of patients. CONCLUSIONS: Our results support the view that early operation is important in ductal pancreatic injury. We recommend transferring children with a suspected ductal injury to a tertiary center with experience in both pediatric ERCP and pancreatic surgery. 相似文献
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Jan Stulik Tobias Rainer Pitzen Jan Chrobok Sabine Ruffing Jörg Drumm Laurentius Sova Ravel Kucera Tomas Vyskocil Wolf Ingo Steudel 《European spine journal》2007,16(10):1689-1694
Anterior cervical plate fixation is an approved surgical technique for cervical spine stabilization in the presence of anterior
cervical instability. Rigid plate design with screws rigidly locked to the plate is widely used and is thought to provide
a better fixation for the treated spinal segment than a dynamic design in which the screws may slide when the graft is settling.
Recent biomechanical studies showed that dynamic anterior plates provide a better graft loading possibly leading to accelerated
spinal fusion with a lower incidence of implant complications. This, however, was investigated in vitro and does not necessarily
mean to be the case in vivo, as well. Thus, the two major aspects of this study were to compare the speed of bone fusion and
the rate of implant complications using either rigid- or dynamic plates. The study design is prospective, randomized, controlled,
and multi-centric, having been approved by respective ethic committees of all participating sites. One hundred and thirty-two
patients were included in this study and randomly assigned to one of the two groups, both undergoing routine level-1- or level-2
anterior cervical discectomy with autograft fusion receiving either a dynamic plate with screws being locked in ap - position
(ABC, Aesculap, Germany), or a rigid plate (CSLP, Synthes, Switzerland). Segmental mobility and implant complications were
compared after 3- and 6 months, respectively. All measurements were performed by an independent radiologist. Mobility results
after 6 months were available for 77 patients (43 ABC/34 CSLP). Mean segmental mobility for the ABC group was 1.7 mm at the
time of discharge, 1.4 mm after 3 months, and 0.8 mm after 6 months. For the CSLP- group the measurements were 1.0, 1.8, and
1.7 mm, respectively. The differences of mean segmental mobility were statistically significant between both groups after
6 months (P = 0.02). Four patients of the CSLP-group demonstrated surgical hardware complications, whereas no implant complications were
observed within the ABC-group (P = 0.0375). Dynamic plate designs provided a faster fusion of the cervical spine compared with rigid plate designs after prior
spinal surgery. Moreover, the rate of implant complications was lower within the group of patients receiving a dynamic plate.
These interim results refer to a follow-up period of 6 months after prior spinal surgery. Further investigations will be performed
2 years postoperatively. 相似文献
9.
A modified technique for catheterization of the pulmonary artery was developed. It involves the passage of a tapered, movable-core, J-tipped guide wire across the right ventricle into the pulmonary artery followed by the advancement of a straightened Grollman pigtail catheter. The technique was successful in 34 of 34 pulmonary artery catheterizations. The method avoids prolonged catheter manipulation within the right ventricle. In addition, since the catheter does not cross the tricuspid valve until the guide wire has been advanced, the occasional complication of the pigtail "hooking" on a tricuspid valve leaflet or chordae tendineae during catheter withdrawal and manipulation is prevented. 相似文献
10.