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951.
We report a case of synovial sarcoma in the neck that was initially considered to be a benign soft-tissue tumour. The mass appeared to originate in the perivertebral space, extending to the spinal canal via the C3/4 and C4/5 neural foramina. The mass also encased the right vertebral artery and this suggested a malignant soft-tissue tumour.  相似文献   
952.
BACKGROUND AND PURPOSE: Diffusion tensor imaging (DTI) was introduced as a good technique to evaluate structural abnormalities in the white matter. In this study, we used DTI to examine anisotropic changes of the pyramidal tracts displaced by chronic subdural hematoma (CSDH).MATERIALS AND METHODS: Twenty-six patients with unilateral CSDH underwent DTI before and after surgery. We measured fractional anisotropy (FA) values in pyramidal tracts of bilateral cerebral peduncles and calculated the ratio of the FA value on the lesion side to that on the contralateral side (FA ratio) and compared the ratios with motor weakness. Moreover, the relationships between FA ratios and clinical factors such as age, sex, midline shift, interval from trauma, and hematoma attenuation on CT were evaluated.RESULTS: FA values of pyramidal tracts on the lesion side were significantly lower than those on the contralateral side (0.66 ± 0.07 versus 0.74 ± 0.05, P < .0001). The FA ratio was correlated to the severity of motor weakness (r2 = 0.32, P = .002). FA ratios after surgery improved significantly compared with those before surgery (0.96 ± 0.08 versus 0.89 ± 0.07, P = .0004). Intervals from trauma and the midline shift were significantly associated with decreased FA ratios (P = .0008 and P = .037).CONCLUSIONS: In patients with CSDH, a reversible decrease of FA in the affected pyramidal tract on DTI was correlated to motor weakness. These anisotropic changes were considered to be caused by a reversible distortion of neuron fibers and vasogenic edema due to the hematoma.

Chronic subdural hematoma (CSDH) is a progressive space-occupying lesion, which may lead to reversible reduction in cerebral function due to brain compression or brain displacement. The causes, clinical characteristics, and therapeutic management of CSDH are well established; however, the detailed physiology, including the mechanisms of appearance with motor dysfunction in patients, is still controversial.14Diffusion tensor imaging (DTI) reveals the tissue microstructure and architecture of white matter tracts, including pyramidal tracts, and extracts the principal diffusivities, mean diffusivities (MD), and fractional anisotropy (FA). Previously, it was reported that decreased FA in the pyramidal tracts on DTI was associated with secondary degeneration and could be a reliable measure of motor weakness.58 The purpose of this study was to investigate changes of DTI in affected pyramidal tracts of patients with CSDH and to evaluate the association between changes of FA and clinical factors such as age, sex, hematoma thickness, midline shift, interval from the trauma, and attenuation on CT.  相似文献   
953.

Purpose  

To investigate the long-term time course of the contrast effects after the intravenous injection of gadofluorine M or gadofluorine P in mice.  相似文献   
954.
The honeybee product propolis and its extracts are known to have biological effects such as antibiotic, anti-viral, anti-inflammatory and anti-tumor activities. This study was designed to investigate whether water-soluble propolis (WSP) inhibits tumor growth. The tumor cell line used was mouse sarcoma 180 (S-180), and its growth was determined in vitro and in vivo with exposure to different concentrations of WSP. The effects of WSP on tumor cells in vitro were evaluated by measuring the intracellular uptake of 3H-thymidine. 3H-thymidine uptake was inhibited in accordance with the concentration of WSP. The minimum concentration of WSP necessary for 3H-thymidine uptake inhibition was 1.0 microg/ml and uptake was suppressed to 88% of the level in non-treated cells at this concentration. In an experiment using tumor-bearing mice, oral administration of WSP was begun 24 hours after transplantation of S-180 cells. WSP was administered to the mice 5 times, every other day for 10 days. The doses were 320 mg/kg (10 mg/mouse) or 960 mg/kg (30 mg/mouse) of body weight. All mice were sacrificed 10 days after transplantation, and tumor growth was evaluated. The orally administered WSP significantly inhibited the growth of transplanted tumors (p < 0.05). Furthermore, histological findings revealed a significant reduction in mitotic cells and tumor invasion of the muscular tissue at both dose-levels of WSP.  相似文献   
955.
AIM: To investigate the effect of pre-existing fetal inflammation on hemodynamics during the first postnatal 24 h in extremely premature infants or= 3 than infants with no fetal inflammation (49% vs 17%) (P=0.04). Infants with fetal inflammation had significantly higher heart rate (P=0.005), catecholamine index (P=0.019) and volume load (P=0.021). CONCLUSION: Histological evidence of fetal inflammation in extremely premature infants is associated with circulatory disturbances over the first 24 h of life and increases in the incidence of IVH >or= 3.  相似文献   
956.
957.
BACKGROUND: Lung injury after cardiopulmonary bypass is a serious complication for infants with congenital heart disease and pulmonary hypertension. Excessive neutrophil sequestration in the lung occurring after reestablishment of pulmonary circulation implies that interaction between neutrophils and pulmonary endothelium is the major cause of lung injury. METHODS: Thirty infants with either ventricular septal defect or atrioventricular septal defect and with pulmonary hypertension were enrolled in this study. We performed continuous pulmonary perfusion during total cardiopulmonary bypass on 16 patients (perfused group) and conventional cardiopulmonary bypass on 14 patients (control group). PaO2/FiO2 and neutrophil counts were assessed from immediately before surgery to 24 hours after termination of cardiopulmonary bypass. RESULTS: PaO2/FiO2 was higher in the perfused group than in the control group, and the difference was significant throughout the study period. Neutrophil counts decreased below prebypass values in both groups at 30 minutes after aortic unclamping, and the difference was significant in the control group but was not in the perfused group. Duration of postoperative ventilatory support was significantly less in the perfused group. CONCLUSIONS: Our study demonstrates that arrested pulmonary circulation during cardiopulmonary bypass is the major risk factor of lung injury and that continuous pulmonary perfusion is effective in preventing lung injury.  相似文献   
958.
Current surgical management of rectal cancer   总被引:2,自引:0,他引:2  
The management of rectal cancer has undergone significant evolution over the past decade with improvements in both surgical technique and adjuvant therapies. The progression of surgical management has been of particular interest, as surgery is the only potentially curative treatment. The major goals of surgery are to optimize oncologic outcome and maintain anorectal and genitourinary function. There are presently two approaches to rectal cancer surgery: total mesorectal excision (TME), which is the gold standard in the Western world, and lateral lymph node dissection, which was originally developed in Japan. Although the results of lateral lymph node dissection are similar to TME with prior radiotherapy, low positive lateral lymph node yields, questionable prognostic significance, and high morbidity are the main drawbacks of this procedure. Despite the current quality of these surgical procedures, locoregional treatment is limited as advanced primary rectal cancer may be associated with systemic spread of disease. Adjuvant therapy therefore plays a key role in obtaining further improvement in survival. In this article, evidence for the use and benefits of lateral lymph node dissection surgery for rectal cancer patients in Japan is reviewed, and its application in association with TME and other modalities considered.  相似文献   
959.

Purpose

Preventing a recurrence of Crohn’s disease is a problem that remains to be solved. We evaluated the impact of using infliximab as a postoperative therapy on preventing the surgical recurrence of Crohn’s disease.

Methods

We performed a pair-matched study comparing 100 patients who had received postoperative infliximab maintenance therapy with those who had not between 1995 and 2010. The patients were matched by gender, Vienna classification and age at the time of the operation. Crohn’s disease-related reoperation was evaluated as surgical recurrence.

Results

In the postoperative infliximab maintenance therapy group, infliximab was administrated within 8 weeks after the operation. The median follow-up period was 36 months in the postoperative infliximab maintenance therapy group and 51 months in the control group. Surgical recurrences were recognized in 37 patients (three in the postoperative infliximab maintenance therapy group and 34 in the control group). A univariate analysis by the Kaplan–Meier method identified a body mass index >18 at the time of the operation (HR 0.19, p = 0.01) and postoperative infliximab maintenance therapy (HR 0.22, p = 0.0022) as factors related to the reduction of surgical recurrence. The multivariate analysis revealed that postoperative infliximab maintenance therapy was the only significant factor preventing surgical recurrence.

Conclusion

Postoperative infliximab maintenance therapy for Crohn’s disease prevents surgical recurrence, at least within 3 years after the operation.  相似文献   
960.
A 25-year-old factory worker sustained inhalation injury and 2 per cent deep burns while fighting a fire in his factory (LSI factory) which was made of new synthetic building materials. He became unconscious and inhaled noxious substances from the smoke. Although he survived the acute stages following injury, his pulmonary function subsequently deteriorated with a damaged trachea and bronchi, repeated attacks of pneumonia, atelectasis, pneumothorax and lung fibrosis, leading to death with hypercapnia (PaCO2 more than 100 mmHg) after 205 days in hospital. Autopsy revealed scarring contraction and dilatation of the trachea and bronchi, acquired bronchiectasis, lobular pneumonia, bleeding, hyperaemia and oedema of the lungs. Systemic administration of corticosteroids was only transiently beneficial in reducing the increased airway resistance.  相似文献   
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