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The anti-migraine drug sumatriptan often induces unpleasant somatosensory side effects, including a dislike of being touched. With a double-blind cross-over design, we studied the effects of sumatriptan and saline on perception (visual analogue scale) and cortical processing (functional magnetic resonance imaging) of tactile stimulation in healthy subjects. Soft brush stroking on the calf (n=6) was less pleasant (p<0.04) and evoked less activation of posterior insular cortex in the sumatriptan compared to the saline condition. Soft brushing activated pain processing regions (anterior insular, lateral orbitofrontal, and anterior cingulate cortices, and medial thalamus) only in the sumatriptan condition, whereas activation of somatosensory cortices was similar in both conditions. Soft brush stroking on the palm (n=6) was equally pleasant in both conditions. One possible mechanism for the activation of pain processing regions by brush stroking is sensitization of nociceptors by sumatriptan. Another possibility is inhibition of a recently discovered system of low-threshold unmyelinated tactile (CT) afferents that are present in hairy skin only, project to posterior insular cortex, and serve affective aspects of tactile sensation. An inhibition of impulse transmission in the CT system by sumatriptan could disinhibit nociceptive signalling and make light touch less pleasant. This latter alternative is consistent with the observed reduction in posterior insular cortex activation and the selective effects of stimulation on hairy compared to glabrous skin, which are not explained by the nociceptor sensitization account.  相似文献   
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We report a case of biventricular implantable cardioverter-defibrillator (ICD) insertion in which standard lead placement techniques could not achieve left ventricular capture. Protrusion of the guidewire beyond a venous stenosis provided adequate left ventricular capture.  相似文献   
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Background

Recent studies have suggested that stent-grafting may improve the treatment outcome of patients with esophageal perforation, but evidence on this is still lacking.

Methods

Data on 194 patients who underwent conservative (43 patients), endoclip (4 patients) stent-grafting (63 patients) or surgical treatment (84 patients) for esophageal perforation were retrieved from nine medical centers.

Results

In-hospital/30-day mortality was 17.5 %. Three-year survival was 67.1 %. Age, coronary artery disease, and esophageal malignancy were independent predictors of early mortality. Chi squared automatic interaction detection analysis showed that patients without coronary artery disease, without esophageal malignancy and younger than 70 years had the lowest early mortality (4.1 %). Surgery was associated with slightly lower early mortality (conservative 23.3, endoclips 25.0 %, stent-grafting 19.0 %, surgery 13.1 %; p = 0.499). One center reported a series of more than 20 patients treated with stent-grafting which achieved an early mortality of 7.7 % (2/26 patients). Stent-grafting was associated with better survival with salvaged esophagus (conservative 76.7 %, endoclips 75.0 %, stent-grafting 77.8 %, surgery 56.0 %; p = 0.019). Propensity score adjusted analysis showed that stent-grafting achieved similar early mortality (p = 0.946), but significantly higher survival with salvaged esophagus than with surgical treatment (p = 0.001, OR 0.253, 95 % CI 0.110–0.585). Primary surgical repair was associated with somewhat lower early mortality (14.6 vs. 19.0 %; p = 0.561) and better survival with salvaged esophagus (85.4 vs. 77.8 %; p = 0.337) than stent-grafting.

Conclusions

Esophageal perforation was associated with a rather high mortality rate in this all-comers population. Stent-grafting failed to decrease operative mortality, but it improved survival with salvaged esophagus. The results of one of the centers indicate that increasing experience with this less invasive procedure may possibly improve the outcome of these patients.  相似文献   
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Background

Controversy exists regarding the effectiveness and safety of laparoscopic Roux-en-Y gastric bypass (LRYGB) in elderly patients. We evaluated our outcomes of LRYGB in patients aged ≥55 years.

Methods

A total of 549 consecutive patients underwent LRYGB as primary operation and 132 were ≥55 years old. Patients were divided in two groups: group <55 years comprised 417 patients, with mean age (±SD) of 41.15 ± 8.47 years; group ≥55 years comprised 132 patients, with mean age of 59.43 ± 3.81 years. Mean preoperative body mass index was 47.01 ± 7.47 and 46.21 ± 7.47 respectively, whereas mean excess weightloss percent (EW%) was 88.06 ± 30.28 and 84.86 ± 29.87 %. Early morbidity (30 days) and outcomes at 6, 12, and 24 months follow-up were evaluated.

Results

Significant difference was found in operative time (84.19 ± 29.05 vs. 90.89 ± 30.95 min, p = 0.03). One conversion to open procedure occurred in group <55 years, whereas three occurred in group ≥55 years (p = 0.04). Intraoperative complications occurred in 22 patients (5.27 %) in group <55 years versus 19 in group ≥55 years (14.39 %), which was statistically significant (p = 0.001). One case of death occurred in the younger group. Overall postoperative morbidity rate was 18.7 % in group <55 years and 25.76 % in group ≥55 years, with no significant difference (p = 0.08). Mean EWL% at 12 months in group <55 years was 65.95.05 ± 26.96 versus 62.61 ± 41.78 in group ≥55 years, whereas at 24 months it was 65.08 ± 29.68 versus 64.48 ± 18.44 with no significant difference between the groups (p = 0.51; p = 0.92).

Conclusions

LRYGB for patients ≥55 years achieves outcomes and complications rates comparable to the younger population. Patients should not be denied bariatric surgery for the age alone.  相似文献   
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