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1.
The purpose of this study was to investigate the application of intravenous iloprost as a novel therapy for the treatment of post-transplant distal limb syndrome (PTDLS). PTDLS is a benign but disabling complication in the first year after renal transplantation. It is characterized by bilateral, often incapacitating pain in the feet and or knees on motion and a significant rise in alkaline phosphatase levels on laboratory evaluation. On MRI, bone marrow edema of the affected bone regions can be demonstrated. PTDLS differs from steroid induced osteonecrosis of the hip in terms of localization, an average cumulative steroid dosage within expected limits, and a benign outcome, as PTDLS does not progress to overt cell necrosis. From August 2003 to April 2005 we treated 10 patients with MRI-proven diagnosis of PTDLS following a standardized regimen of intravenous iloprost over 5 days. Iloprost led to prompt pain relief measured on a visual analogous scale (VAS) ranging from 1 to 10 (5.6 +/- 1.5 before vs. 2.1 +/- 1.3 after treatment, p = 0.0004). PTDLS represents a benign but disabling complication following renal transplantation. Intravenous iloprost might be a promising therapeutic concept leading to a quick relief of symptoms without relevant side effects.  相似文献   
2.
P J George  G Clarke  S Tolfree  C P Garrett    M R Hetzel 《Thorax》1990,45(4):248-253
To determine whether endoscopic laser treatment improves both ventilation and perfusion in patients with advanced lung cancer, krypton-81m ventilation and technetium-99m labelled macro-aggregate perfusion scanning was performed immediately before and two or four days after treatment in a consecutive series of 28 patients. Twelve patients had not received any other treatment before laser therapy and 16 had undergone previous treatments that included radiotherapy. Ventilation and perfusion were quantified by expressing the number of counts in the affected lung as a percentage of the total counts. Ventilation and perfusion improved after laser treatment in 23 patients (82%). The mean ventilation score in the affected lung rose by 50% (p less than 0.001) and the mean perfusion score rose by 24% (p less than 0.001). Incremental changes in ventilation and perfusion scores were positively correlated (r = 0.80). Mean spirometric values, six minute walking distance, the Karnofsky performance index, and breathlessness and wellbeing scores also improved significantly. Patients with main bronchial obstruction who had had no radiotherapy showed the most striking improvements. It is concluded that the removal of intraluminal tumour from the bronchial tree leads to matched improvements in ventilation and perfusion in most patients and that this is associated with valuable improvement in symptoms.  相似文献   
3.
The effects of local tumor hyperthermia on regional lymph node metastases are inconclusive. We studied the effects of hyperthermia on the incidence of popliteal, femoral, and abdominal lymph node metastases in C57BL/6 mice with primary B16 melanomas (F10 variant) growing subcutaneously in the left foot. Tumors were heated to 42.3, 43.5, and 44.2 degrees C for 90 minutes either 7 days after inoculation of 5 X 10(4) viable cells (microscopic tumor = mic) or when the tumors were approximately 3 mm in diameter (macroscopic tumor = mac). Femoral lymph node metastases occurred in 0/21 control animals and in 8/22 (36%), 11/19 (58%), and 11/17 (65%) animals whose primary tumors were heated to 42.3, 43.5, and 44.2 degrees C, respectively. For all three treatments, the increase in metastases as compared to controls was statistically significant (p less than 0.004, Fisher's exact test). The incidence of abdominal lymph node metastasis was slightly higher in the treated groups than controls. Twenty of 21 (95%) control mice developed popliteal lymph node metastases and hyperthermia-induced increases could not be demonstrated. Fifteen of 21 control mice killed 3 weeks after amputation of tumor-containing leg had pulmonary metastases with an average of 6 +/- 4 (standard deviation) lesions per affected mouse. Pulmonary metastases occurred in 22/22 (100%), 17/19 (89%), and 13/17 (76%) of mice whose tumors were heated to 42.3, 43.5, and 44.2 degrees C, respectively. The numbers of metastases for affected mice were significantly increased compared to controls for tumors heated to 43.5 and 44.2 degrees C (28 +/- 43, 43 +/- 52, 119 +/- 121, p greater than 0.02, p less than 0.006, p less than 0.002, for two sample T-test). While 0/8 mic tumors were cured 5/9 mac tumors heated to 44.2 degrees C disappeared (p less than 0.03, Fisher's exact test) and there was a growth delay in the remaining mice. Mic tumors, heated to 43.5 degrees C, had an accelerated onset of growth while mac tumors heated to this temperature had a slight growth delay. Growth of both mic and mac primary tumors heated to 42.3 degrees C was similar to controls. These results show that therapeutic and subtherapeutic local hyperthermia increases metastases to regional lymph nodes and to lungs even when primary tumor growth rate is partially or totally controlled.  相似文献   
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Photodynamic therapy has been used in the management of patients with malignant brain tumors even though the effects of this form of treatment on the adjacent normal brain are incompletely characterized. The authors examined, in sequential experiments, morphologic alterations affecting the cerebral cortex in rats injected with Photophrin II and exposed to light. Initially, minimal cell alterations, including cisternal swelling of both endoplasmic reticulum and Golgi apparatus, involved only neurons located in the superficial layers of the cerebral cortex exposed to light. These changes spread, over a period of several hours, from the surface to the bottom of the cortex and eventually involved the entire cortical segment exposed to light. The earliest structural signs of lethal injury to neurons developed over a period of 18 hours after porphyrins had been photoactivated and astrocytes had been severely damaged. Signs of lethal injury to neurons included an increase in the number of mitochondrial cristae and appearance of amorphous electron-dense deposits within swollen mitochondria. The appearance of these alterations was followed by segregation of intracytoplasmic organelles and fragmentation of nuclear and cytoplasmic membranes. The tissue changes, including those involving neurons, eventually progressed to coagulation necrosis at 48 hours. These observations suggest that prophyrins injected to rats (48 hours before photoactivation) cause swelling and necrosis of astrocytes. This is followed by neuronal necrosis, which appears at two time intervals; the initial neuronal necrosis occurs after the astrocytic disintegration. A second type of neuronal alteration appears after microvessels become thrombosed and ischemia is likely to develop.  相似文献   
7.
Zusammenfassung An vier gesunden jugendlichen Versuchspersonen wurde für den Multifidus-Anteil des M. erector trunci die Häufigkeit synchroner Entladungen zweier differenter Faseraktionspontentiale bei ein- (rechts-) und beidseitiger Ableitung untersucht. Die Beobachtungen genügten den Bedingungen für eine statistische Auswertung. Die Häufigkeit synchroner Impulse wurde durch die prozentuale Differenz der errechneten (= zufälligen) abzüglich der gezählten (= beobachteter) Koinzidenzen ausgedrückt. Die so erhaltenen Mittelwerte (Synchronisationsraten) lagen — in Entsprechung zu den von Buchthal für die Extremitätenmuskeln erhobenen Werten — sowohl für die einseitigen wie für die beidseitigen Ableitungen zweier differenter Aktionspotentiale unter ±10%. Ein signifikanter Unterschied der Synchronisationsrate bei den einzelnen Versuchspersonen fand sich nicht, ebenso keine Beziehung zwischen der Häufigkeit synchroner Entladungen und der mittleren Frequenz. Für die ausgewerteten Beobachtungen wurde die AS-Dauer bei leichter Halteaktivität bestimmt. In einzelnen Fällen konnte eine vollkommene Synchronisation zweier Motoneuronen-Entladungen und eine Abhängigkeit der Aktionspotentiale vom Atemcyclus beobachtet werden.Mit 6 TextabbildungenDie Untersuchungen wurden mit Unterstützung der Deutschen Forschungs-gemeinschaft durchgeführt.  相似文献   
8.
BackgroundPreoperative carbohydrate loading is a component of Enhanced Recovery After Surgery (ERAS) protocols, but there is limited literature in bariatric surgery patients.ObjectivesThe objective of this study was to characterize the impact of preoperative carbohydrate loading on postoperative bariatric surgery outcomes.SettingUniversity Hospital.MethodsPatients undergoing a primary minimally invasive Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG) between 2018 and 2020 were randomized to standard management or intervention. Standard management patients were nothing by mouth (NPO) after midnight prior to surgery. Intervention patients consumed 2 carbohydrate drinks: 1 the night before and another 3 hours prior to surgery. Primary outcomes analyzed included postoperative nausea and vomiting (PONV), length of stay, and overall complications.ResultsIn total, 134 patients were analyzed: 64 intervention (47.8%) and 70 (52.2%) standard. In the end, 7% and 15% of patients were lost to follow-up at 6-weeks and 3-months, respectively. There was no statistically significant difference in length of stay (2.0 ± 1.2 vs 2.1 ± .9 d; P = .65) or postoperative outcomes between the 2 groups. There were no episodes of aspiration among the intervention group. Among RYGB patients, intervention patients had a shorter duration of nausea compared with standard patients. There was no significant difference in glycemic control among patients with and without diabetes.ConclusionsPreoperative carbohydrate drinks can be administered to bariatric surgery patients without significant risks. Carbohydrate loading preoperatively can decrease the duration of PONV in RYGB patients. Carbohydrate drinks can be safely included in bariatric ERAS protocols for patients with and without diabetes, although the benefits remain unknown.  相似文献   
9.
Carotid restenosis after endarterectomy is observed in up to 24.1% of patients with long-term follow up. Indication for reintervention in asymptomatic patients however should be reserved for greater than 80% stenosis. Treatment options include repeat surgical reconstruction as well as intraoperative or percutaneous balloon angioplasty +/- stenting. We compared our past experience with 66 operative reconstructions in 64 patients with a recent series of 60 patients who underwent intraoperative balloon-dilatation and stenting. After conventional surgery 2 patients (3.1%) suffered a permanent neurological deficit, one patient developed a TIA (1.5%). After intraoperative dilation and stenting 8 patients (13.3%) suffered a stroke; 2 patients died after surgery (one stroke, one myocardial infarction) (mortality 3.3%). When compared to conventional operative repair intraoperative carotid balloon angioplasty and stenting of restenosis is complicated by a substantial increase in morbidity and mortality and cannot be recommended as routine therapy.  相似文献   
10.
OBJECTIVE: This randomized, double-blind, placebo-controlled study with treatment lasting 16 weeks and withdrawal lasting 6 weeks tried to determine whether stopping nitrates has an effect on left-ventricular end-systolic volume in patients with heart failure who were chronically treated with captopril and diuretics. PATIENTS AND METHODS: The study group comprised 29 patients with previous myocardial infarction, symptoms of mild-to-moderate heart failure, ejection fraction below 40%, no exercise-induced angina and no electrocardiographic signs of ischemia. After all patients had been treated with captopril (target dose: 25 mg twice daily), diuretics and the study drug (target dose: 40 mg isosorbide dinitrate twice daily or placebo) for 16 weeks, the study drug was withdrawn. The patients were then maintained on captopril and diuretics at constant doses for a 6-week withdrawal period. Radionuclide ventriculography with right-heart catheterization was performed at rest and during supine bicycle exercise after 16 weeks of double-blind treatment and at the end of the 6-week withdrawal period. RESULTS: The changes in resting parameters following the withdrawal of the study drug were not different between the groups. At comparable maximum workload (placebo group 68 +/- 15 W, nitrate group 68 +/- 20 W), nitrate withdrawal caused a decrease in ejection fraction (placebo withdrawal: +0.8 +/- 4.0%; nitrate withdrawal: -2.7 +/- 4.3%, p < 0.02) and increases in left-ventricular end-diastolic volume (-9 +/- 35 vs. 23 +/- 48 ml, p < 0.02) and end-systolic volume (-9 +/- 33 vs. +24 +/- 47 ml; p < 0.01). CONCLUSION: The addition of nitrates to a baseline therapy with captopril and diuretics might reduce exercise-induced left-ventricular dilatation in patients with heart failure from coronary disease.  相似文献   
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