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41.
We have previously described the development of new hepatic surgical techniques using the ultrasonic surgical dissector. With 10 years' experience, we have found that major liver resections have been simplified and that the technique is repeatable in hands other than our own. Thirty-three patients had 37 tumors, averaging 5.65 cm in size, resected with an average blood loss of only 1,020 mL per case, which included 5 right trisegmentectomies, 12 lobectomies, 15 segmental resections, and 4 subsegmental resections. Twenty-two patients had metastatic colorectal cancer. Blood transfusion requirements averaged only 2.24 units in long-term survivors, which was significantly less than the 3.5 units received by patients who have since died (p = 0.092). There were no operative deaths. The median survival of these 22 patients was 56 months, and the 5-year actuarial survival rate was 35%. All of the early deaths occurred in patients with more than four tumors, and no patient with less than four tumors died before 42 months with recurrent disease. Six patients had bilateral tumors, and the fact that patients survived into the fourth and fifth post-resectional year indicates that resection was worthwhile. All these patients had Dukes' C primary tumors, but we found no statistical difference in survival between patients with Dukes' B and Dukes' C lesions. The results indicate that hepatic resection with the ultrasonic surgical dissector decreases blood loss, requires few transfusions, is safe to perform, and is associated with excellent long-term survival.  相似文献   
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Assessment of attitudes amongst health care professionals to suicide prevention reveals a considerable degree of doubt with regards to its feasibility and appropriateness. The various professional groups may vary considerably in the degree of negative attitudes which they exhibit. Such findings suggest that there is an urgent need to ensure that health care professionals are fully informed about the key facts concerning suicide and preventive strategies. Key elements of clinical practice and service organization with regards to suicide prevention are discussed.  相似文献   
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Introduction There have been many surgical techniques described for the treatment of pilonidal sinuses. Recurrent disease causes significant morbidity particularly with time from work. Aim To assess the rhomboid flap's role in promoting one‐stage primary healing in pilonidal disease and to evaluate the morbidity and recurrence. Methods Fifty‐three patients were prospectively recruited of which 27 had previous multiple abscess formation requiring surgical drainage from their pilonidal disease, although none had acute disease at the time of surgery. By using the transposition flap, we were able to obliterate the natal cleft and therefore the rolling action of the buttocks between the cleft in these patients and thereby remove one of the factors involved in pilonidal disease. Hospital stay, healing time, wound infection, wound breakdown and recurrence were noted. Results There were 47 males and 6 females with a median age of 28 years (range 16–64 years). Median follow‐up was 24 months (range 3–36 months). Post‐operative morbidity involved superficial wound infection in 7 (13%) which settled with out‐patient dressings. There were four recurrences (7%), two occurred between the flap and the anal canal, and the other two in the flap margin needing intervention. All the patients healed their wounds and the median healing time was 14 days. Conclusion As this condition affects a predominantly young population causing significant time off from work, we feel that the Rhomboid Flap is useful for difficult cases in that it allows early return to full activity and does not necessitate prolonged postoperative care.  相似文献   
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Brain structures activated during ethanol withdrawal have been mapped by visualizing c-fos mRNA expression. The regional distribution of c-fos mRNA in brain during ethanol withdrawal can be mimicked by acute injection of N-methyl-D-aspartic acid (NMDA) and is stereospecifically blocked by the NMDA receptor antagonist, MK-801. The findings reveal that the dentate gyrus and piriform cortex are selectively activated during ethanol withdrawal and suggest that this may be mediated by glutamate activation of NMDA receptors.  相似文献   
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The objectives of this study were to use computer-generated phantoms containing real subject motion to: (1) compare the sensitivity of four commonly used fMRI software packages and (2) compare the sensitivity of three statistical analysis strategies with respect to motion correction. The results suggest that all four packages perform similarly in fMRI statistical analysis with SPM2 having slightly higher sensitivity. The most sensitive analysis technique was to perform motion correction and include the realignment parameters as regressors in the general linear model. This approach applies to all four packages examined and can be most beneficial when stimulus-correlated motion is present.  相似文献   
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Adenosine as a vasodilator in primary pulmonary hypertension   总被引:7,自引:0,他引:7  
BACKGROUND. The acute administration of vasodilator drugs to patients with primary pulmonary hypertension has been advocated to identify those with reversible pulmonary vasoconstriction. Unfortunately, the usefulness of the drugs currently available is limited by accompanying systemic hypotension. A vasodilator with effects confined to the pulmonary circulation would therefore be advantageous in such patients. METHODS AND RESULTS. The purine nucleoside adenosine was infused into the pulmonary artery in seven patients with primary pulmonary hypertension (baseline pulmonary vascular resistance [PVR], 442-1,295 dyne/cm/sec-5) to determine its effect on PVR. In all patients, there was a dose-dependent and significant reduction (mean maximal percent decrease from baseline, 38.9%; p less than 0.001) in PVR mediated through a decrease in pulmonary artery pressure and an increase in cardiac output. Systemic vascular resistance (SVR) also decreased, but the ratio of PVR to SVR decreased (maximal mean percent decrease from baseline) by 10.5% (p less than 0.025), indicating that adenosine has a preferential vasodilator effect on the pulmonary circulation when administered in this manner. CONCLUSIONS. Because of its pharmacokinetic and vasodilator properties, adenosine may have a specific role in the investigation of primary pulmonary hypertension.  相似文献   
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