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11.
 In order to determine the dynamics of hematopoietic cell turnover, proliferative activity and incidence of apoptosis (programmed cell death) were evaluated in bone marrow trephine biopsies. Selection of patients (20 in each group) included in addition to a control group, idiopathic thrombocytopenia (ITP), reactive thrombocytosis (TH), secondary polycythemia-smokers' polyglobuly (PG), primary (essential-hemorrhagic) thrombocythemia (PTH), polycythemia vera (PV), and finally acute myeloid leukemia (AML). Apoptosis was demonstrated by the in situ end-labeling technique (ISEL) and proliferative activity by applying the monoclonal antibody PC10 raised against proliferating cell nuclear antigen (PCNA). To assess dynamic features of hematopoiesis, an index was calculated consisting of the ratio between PCNA-positive nuclei and the apoptotic cell fraction. This factor was termed the hematopoietic turnover index (HTI). Morphometric analysis revealed that the HTI was significantly increased in AML and PV. According to cell culture studies both disorders are characterized by either a prevalent proliferation of the myeloid or erythroid cell mass. On the other hand, PG, PTH, and TH showed no relevant enhancement of this index in comparison to the control specimen. In vitro experiment results are in keeping with the finding that PG and PTH are not associated with a significant expansion of the erythroid lineage (CFU-E). Similar to ITP and TH, in PTH megakaryocyte proliferation (CFU-MEG) is the predominant feature of cell turnover. Differences between PTH and TH are in line with the reduced in vitro formation of CFU-MEG in the latter disorder. In conclusion, our in situ study on turnover rates of the bone marrow in various neoplastic and reactive lesions extends previous experimental data on hematopoietic cell kinetics. Received: 10 March 1997 / Accepted: 18 May 1997  相似文献   
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Long-term outcome of completion gastrectomy for nonmalignant disease   总被引:1,自引:1,他引:0  
Between 1989 and 1995 we performed completion gastrectomy for non-malignant disease in 21 patients (11 men and 10 women, mean age 48.4 years). These patients had undergone a total of 48 prior gastric operations. Indications for completion gastrectomy in this group were anastomotic ulceration with stricture in eight patients, alkaline reflux gastritis and/or esophagitis in eight, postsurgical gastroparesis in two, gastroesophageal necrosis in two, and gastrocutaneous fistula in one. Major preoperative symptoms included nausea and vomiting in 16 cases, abdominal pain in 15, dysphagia in 14, heartburn in seven, and weight loss in five. Following completion gastrectomy, five patients (24%) had serious complications and there was one postoperative death (5%). Five patients were lost to follow-up. For the remaining 15 patients, mean follow-up has been 30 months with a range of 1 to 70 months. These patients were all interviewed and eight (53%) report significant improvement, two (13%) report moderate improvement, and four (27%) report no improvement; one patient (7%) has had worsening of symptoms since undergoing completion gastrectomy. The average body weight index was essentially unchanged after completion gastrectomy. We conclude that completion gastrectomy with Roux-en-Y esophagojejunostomy results in a favorable outcome in the majority of selected patients with diseases of the foregut who are unresponsive to less radical treatment. Presented at the Thirty-Seventh Annual Meeting of The Society for Surgery of the Alimentary Tract, San Francisco, Calif., May 19–22, 1996.  相似文献   
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Dissociative responses to trauma have been hypothesized to be associated with long-term increases in psychopathology. The purpose of this study was to examine dissociative responses to premilitary, combat-related and postmilitary traumatic events and long-term psychopathology in Vietnam combat veterans with (n = 34) and without (n = 28) posttraumatic stress disorder (PTSD). PTSD patients reported higher levels of dissociative states at the time of combat-related traumatic events than non-PTSD patients. Higher levels of dissociative states persisted in PTSD patients in the form of higher levels of dissociative states in response to postmilitary traumatic events. In addition, dissociative responses to combat trauma were associated with higher long-term general dissociative symptomatology as measured by scores on the Dissociative Experience Scale, as well as increases in the number of flashbacks since the time of the war. These findings are consistent with previous formulations that dissociation in the face of trauma is a marker of long-term psychopathology.  相似文献   
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PURPOSE: The development of overall survival of a DOSAK (German-Austrian-Swiss Cooperative Group on tumours of the maxillofacial region) clinic's overall population comprising a time period of more than 20 years (1983-2004) should be assessed. At a cutoff date (January 1st, 1997), a change from a primarily surgically based to a consequent multi-modality treatment regimen was implemented. The periods of time before and after that change should be compared. METHODS AND PATIENTS: The data of the DOSAK registry entries on 1038 patients suffering from primary untreated oral and oropharyngeal carcinomas were updated with respect to follow-up and mortality data to achieve a 100% quality of follow-up. The end point (death) was reached in 67% of the overall population. Statistical analysis was carried out by the Trium Analysis Online corporation, Munich. RESULTS: The portion of female and older tumor patients increased, more than half of all tumor patients were clearly in stage IV of the disease at first referral. The portion of patients operated on persisted approximately (80%), the portion of additional treatment modalities could be increased considerably. The fact of a bony infiltration by the tumor and the operability remained highly significantly relevant for survival in multivariate analysis, despite of multi-modality treatment. The survival rate of the patients remained significantly dependent on the clinical stage of the disease in multivariate analysis but could be improved by 10% in the clinical stages II and III and in the patients who could not be operated on. All in all, the cutoff date was statistically relevant for survival in multivariate analysis, i.[Symbol: see text]e. the change in the treatment regimen had a verifiable positive effect on the survival of a unicentric overall population. CONCLUSION: Survival improvement in an overall population via change in treatment strategy is possible in relatively short time; the clinical stages II and III and the non-operable patients have the greatest benefit from a multi-modality treatment.  相似文献   
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BACKGROUND CONTEXT: Posterior lumbar interbody fusion (PLIF) is a popular method of arthrodesis for surgical treatment of instabilities and degenerative conditions of the spine. With the introduction of threaded titanium cage devices, surgeons began performing PLIF procedures using these cages as stand-alone devices. Complications have been reported, however, including pseudarthrosis with persistent pain. Outcomes after revision surgical treatment for these patients with failed PLIF are not known. PURPOSE: To prospectively evaluate clinical outcomes of revision fusion surgery in patients who previously underwent posterior lumbar interbody fusion with stand-alone metallic cages resulting in pseudarthrosis. STUDY DESIGN/SETTING: Prospective case series. METHODS: Nineteen patients referred to the senior author were evaluated and diagnosed with pseudoarthrosis having previously undergone a PLIF procedure with stand-alone metallic cages. History, physical exam, and imaging studies were performed preoperatively and postoperatively. All underwent revision posterolateral fusion with iliac crest graft and pedicle screw instrumentation. Patient demographics, SF-36, and Oswestry Disability Index (ODI) data were collected prior to surgery and two years postoperatively. RESULTS: Patients undergoing revision fusion surgery were found to have had extensive facetectomies and pseudarthrosis intraoperatively. Outcomes data was collected on eighteen of nineteen patients (95%). Mean clinical follow up was 3.2 years (range 2.5-3.5 years). Seventeen patients (94%) achieved a solid fusion. Improvement was noted in seven of eight SF-36 sub-categories, but was significant only in two (Physical Function and Role Emotional). There was no significant difference in ODI scores. CONCLUSIONS: Pseudarthrosis should be considered in the differential diagnosis if severe symptoms persist in patients who undergo PLIF with stand-alone metallic cages. Successful revision fusion did not always correlate with improved clinical outcomes in these challenging patients undergoing further surgery. Performing PLIF using stand-alone metallic cages, especially after total resection of the facet joints, is not advocated unless supplemental instrumentation is utilized.  相似文献   
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The purpose of this study was to evaluate the dose to normal tissues as a function of increasing margins around the lumpectomy cavity in accelerated partial breast irradiation (APBI) using 3D-conformal radiotherapy (3DCRT). Eight patients with Stage 0-I breast cancer underwent treatment planning for 3DCRT APBI. The clinical target volume (CTV) was defined as a 15-mm expansion around the cavity limited by the chest wall and skin. Three planning target volumes (PTV1, PTV2, PTV3) were generated for each patient using a 0, 5-, and 10-mm expansion around the CTV, for a total margin of 15, 20, and 25 mm. Three treatment plans were generated for every patient using the 3 PTVs, and dose-volume analysis was performed for each plan. For each 5-mm increase in margin, the mean PTV:total breast volume ratio increased 10% and the relative increase in the mean ipsilateral breast dose was 15%. The mean volume of ipsilateral breast tissue receiving 75%, 50%, and 25% of the prescribed dose increased 6% to 7% for every 5 mm increase in PTV margin. Compared to lesions located in the upper outer quadrant, plans for medially located tumors revealed higher mean ipsilateral breast doses and 20% to 22% more ipsilateral breast tissue encompassed by the 25% IDL. The use of 3DCRT for APBI delivers higher doses to normal breast tissue as the PTV increases around the lumpectomy cavity. Efforts should be made to minimize the overall PTV when this technique is used. Ongoing studies will be necessary to determine the clinical relevance of these findings.  相似文献   
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