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Intracerebral vascular reactivity induced by the nitric oxide (NO) donor isosorbide dinitrate (IDN, 5 mg sublingually) is more major and longer-lasting in migraine patients who develop delayed headache in response to the drug. The headache is purportedly due to neuronally-mediated vascular mechanisms. Indomethacin inhibits prostaglandin synthesis, which is involved in NO generation. Indomethacin also decreases cerebral blood flow by constricting precapillary resistance vessels. In the present study, the hemodynamic effects of indomethacin were evaluated in migraine patients and healthy controls by means of transcranial Doppler monitoring. Indomethacin caused a significant decrease in mean flow velocity in the middle cerebral artery. This was an additional effect to the mean velocity decrease induced by IDN. The interactions between the two drugs suggest that their effects on cerebral hemodynamics (and pain) may be of relevance both in understanding the role of NO in migraine pathogenesis and in evaluating symptomatic treatments for migraine attacks.  相似文献   
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Laparoscopic bile duct injuries. Risk factors, recognition, and repair.   总被引:18,自引:0,他引:18  
Records of 11 patients undergoing biliary reconstruction after laparoscopic cholecystectomy are reviewed. Ductal injuries resulted from failure to define the anatomy of Calot's triangle. Risk factors include scarring, acute cholecystitis, and obesity. Presenting findings included anorexia, ileus, failure to thrive, pain, ascites, and jaundice. All patients required hepaticojejunostomies, which were multiple and above the hepatic bifurcation in four patients. Given the extensive nature of these injuries and the frequent need for intrahepatic anastomosis and early stenosis of repairs by referring physicians, we recommend reconstruction be undertaken by an experienced hepatobiliary surgeon. To avoid injuries, a greater appreciation of risk factors and anatomic distortion and variance and strict adherence to principles of dissection and identification of anatomic structures are suggested. The use of cholangiography and a low threshold for conversion to the open procedure are advised.  相似文献   
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The effects of linoleic acid, linoleic acid anilide, and arachidonic acid on the expression of CD11b/CD18, CD11c/CD18 integrins and l-selectin on human neutrophils were studied by flow cytometry in a whole blood assay. None of these compounds had any effect on the basal expression of CD11b, CD11c, or l-selectin in the concentration range of 20–100 μM. However, linoleic acid at a concentration of 1000 μM slightly up-regulated CD11b and CD11c by a factor of 2.1 and 1.7, respectively. Linoleic acid, linoleic acid anilide, and arachidonic acid did not affect the formyl-methionyl-leucyl-phenylalanine induced up-regulation of CD11b or CD11c. However, linoleic acid and linoleic acid anilide slightly inhibited the phorbol myristate acetate (PMA)-induced expression of CD11b, which was decreased by 27 and 21% at concentrations of 100 and 1000 μM, respectively. Likewise, arachidonic acid at 40 μM inhibited the PMA-induced expression of CD11b by 19%. Our results suggest that linoleic acid, linoleic acid anilide, and arachidonic acid do not dramatically affect the expression of leukocyte adhesion molecules in a whole blood assay. Received: 17 February 1997  / Accepted: 5 May 1997  相似文献   
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Self-efficacy in weight management   总被引:10,自引:0,他引:10  
Self-efficacy is an important mediating mechanism in advancing understanding of the treatment of obesity. This study developed and validated the Weight Efficacy Life-Style Questionnaire (WEL), improving on previous studies by the use of clinical populations, cross-validation of the initial factor analysis, exploration of the best fitting theoretical model of self-efficacy, and examination of change in treatment. The resulting 20-item WEL consists of five situational factors: Negative Emotions, Availability, Social Pressure, Physical Discomfort, and Positive Activities. A hierarchical model was found to provide the best fit to the data. Results from two separate clinical treatment studies (total N = 382) show that the WEL is sensitive to changes in global scores as well as to a subset of the five situational factor scores. Treatment programs may be incomplete if they change only a subset of the situational dimensions of self-efficacy. Theoretical and clinical implications are discussed.  相似文献   
100.
Background: The Heller-Dor operation has recently been proposed for the treatment of esophageal achalasia even via a laparoscopic approach. Methods: To measure the medium-term effectiveness of this new minimally invasive technique, an evaluation of pre- and postoperative symptoms, esophagogram, endoscopic findings, esophageal manometry, and pH monitoring was prospectively designed in 43 patients with primary esophageal achalasia. The mean clinical follow-up for all the patients is 12 months (range 3–43), while the mean radiological follow-up is 11 months (range 1–23). Endoscopic data 1 year after surgery are currently available for 27 patients (63%), whereas a 12-month (range 1–26) functional follow-up (including manometric and pH-monitoring studies of the esophagus) is currently available for 35 patients (81.4%). Results: No dysphagia was reported in 38 cases (88.4%); two (4.6%) complained of occasional swallowing discomfort which regressed spontaneously; two (4.6%) had persistent dysphagia which regressed with pneumatic dilatation. One patient (2.8%) reported mild occasional dysphagia after a 1-year asymptomatic period. Preoperatively, esophagograms showed an average maximum diameter of 40.6 ± 9.1 mm which decreased to 24.1 ± 6.0 mm after operation. Mean lower esophageal sphincter (LES) resting and residual pressures decreased significantly from 28.6 ± 10.7 mmHg to 8.8 ± 4.1 mmHg and from 17.0 ± 9.7 mmHg to 4.7 ± 4.0 mmHg, respectively (p < 0.0001). These effects on esophageal diameter and LES function seem to persist over time. The complete absence of any peristaltic contractions recorded preoperatively in all cases remained unchanged after surgery in all but four patients. However, this rare recovery of peristalsis proved to be transient, and patients revealed a manometric impairment of their esophageal body function, but without complaining of dysphagia. Twenty-four-hour pH monitoring showed abnormal gastroesophageal reflux episodes in two (5.7%) of the 35 patients who were monitored: one was asymptomatic; the other had heartburn and endoscopically demonstrated grade II esophagitis. Conclusions: Laparoscopic Heller-Dor operation achieves excellent medium-term results which, together with the already-demonstrated advantages of a minimal surgical trauma and rapid convalescence, validate the use of such a minimally invasive approach to treat patients with primary achalasia of the esophagus. Received: 19 March 1996/Accepted: 15 May 1996  相似文献   
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