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71.
72.
The purpose of our study was to compare power Doppler sonography (US) and conventional color Doppler US in the diagnosis of acute appendicitis by revealing local signs of hyperemia. One hundred consecutive patients (46 males and 54 females, ages 7–61 years; mean, 24.7 years) with clinically suspected acute appendicitis were prospectively examined with power Doppler US and conventional color Doppler US. Of 38 patients who subsequently underwent surgery, appendicitis was proven in 34. The remaining 62 patients who were not submitted to surgery had no clinical evidence of appendicitis over a 2- to 6-month follow-up. At gray-scale US, the appendix was visualized in 30 (88.2%) of the 34 cases with pathologically proven acute appendicitis. Power Doppler US depicted a moderate to marked hypervascularity of the appendiceal wall and surrounding mesoappendix in 28 (93.3%) of these 30 patients. At conventional color Doppler US, flow signal within the appendiceal wall and surrounding mesoappendix was shown in only 21 (70%) of 30 cases (P<0.05). No false-positive diagnosis was made at either power or color Doppler US among the 62 patients without appendicitis. Power Doppler US is more sensitive than conventional color Doppler imaging for revealing signs of local hyperemia in acute appendicitis.  相似文献   
73.
Background: Although cholecystokinin (CCK) is involved in the short-term regulation of satiety, it has not been investigated in obese patients subjected to bariatric restrictive operations. Methods: 8 morbidly obese patients (BMI 49.1 ± 6.9), 7F and 1M, were investigated before and after vertical banded gastroplasty (VBG). 6 healthy lean volunteers served as the control group. CCK was determined (RIA) after an overnight fast and after the administration of an acidified (pH 3) liquid meal. Blood samples were taken 45 min before the meal, 5 min after it and then every 30 min for 3 hours. Results: There were no differences between groups in basal CCK levels. However, the peak of CCK after the meal was significantly higher (P <0.01) in obese patients after VBG (24.9 ± 18 pmol/l) than before VBG (9.8 ± 6.7 pmol/l) and when compared with the control group (8.0 ± 6.3 pmol/l).The time needed to reach the peak was longer in healthy volunteers (105 ± 24.9 min) than in obese patients before VBG (45 ± 40 min) and after VBG (7.5± 12 min) (P<0.01). Conclusions: VBG increases the peak of CCK secretion and shortens the time to reach it. These changes could contribute to the satiety effects of gastric restrictive operations.  相似文献   
74.
BACKGROUND: Graft shortage makes multiorgan procurement mandatory. We describe the results of a simplified method for the en bloc procurement of multiple organs, which permits isolated transplantation of all abdominal grafts, including the pancreas and the small bowel, to different recipients. METHODS: Three hundred forty-three multiorgan procurements were done with a simplified en bloc technique. RESULTS: None of the 1374 grafts that were procured sustained injuries that potentially precluded transplantation. Seventy-two grafts that were procured from 18 donors (5%) who were diagnosed with a neoplasm were discarded. Overall, 339 grafts that were procured from 325 donors were discarded because of specific contraindications, and 963 grafts (74%) were transplanted. Ninety-seven pancreata were transplanted. In 3 instances the pancreas and the small bowel were procured simultaneously and transplanted to different recipients. A total of 287 liver grafts were also transplanted at 13 different institutions. In 42 instances, the liver was not allocated to our center. Forty liver teams (95%) from 11 different institutions agreed to procure their grafts according to the simplified en bloc technique. Our team performed 18 procurements, and a surgeon from the liver transplantation team, who was assisted by one of the members of our team, performed 22 procurements. In all, 576 kidneys were transplanted, either alone or simultaneously, with other abdominal grafts at 15 different institutions. CONCLUSIONS: This procurement method has high yields, allows pancreas and small-bowel procurement, and can be learned readily.  相似文献   
75.
BACKGROUND: Celsior is an extracellular-type, low-viscosity, preservation solution already used for heart, lung, liver, and kidney transplantation. We report the results of a single-center, prospective, randomized pilot study specifically designed to compare the safety profile of Celsior solution with University of Wisconsin (UW) solution in clinical pancreas transplantation. METHODS: A total of 105 consecutive procurements were randomized to graft preservation with UW (n=53) solution or Celsior (n=52) solution. The groups were comparable with regard to all donor and recipient characteristics. RESULTS: Five grafts were discarded and 100 grafts (50 UW vs. 50 Celsior) were transplanted. Mean cold and warm ischemia times were 11.0 +/- 2.1 hr and 37.2 +/- 6.0 min for UW compared with 10.8 +/- 1.8 hr and 38.1 +/- 5.9 min for Celsior (P =not significant). Delayed endocrine pancreas function was recorded in one graft preserved with UW solution. Eleven recipients (UW 12% vs. Celsior 10%, P =not significant) required a relaparotomy. The mean serum levels of glucose, amylase, and lipase remained comparable between the study arms at equivalent intervals after transplantation. One recipient died with functioning grafts in each study arm; two further grafts were lost to arterial thrombosis (Celsior) and chronic rejection (UW), respectively. Actuarial 1-year patient and graft survival rates overlapped in the two study arms (98% and 96%, respectively). CONCLUSIONS: Within the range of cold ischemia time reported in this study, UW and Celsior solutions have similar safety profiles for pancreas preservation.  相似文献   
76.
Surgical technique of total thyroidectomy is nowadays well known. Technology could determine some improvement of this kind of surgery. Two groups of patients that underwent total thyroidectomy were compared retrospectively. In group 1 we described 105 total thyroidectomies performed with ultrasonically activated shears; in group 2, 76 performed with conventional methods of haemostasis. Comparing the two groups for several parameters, it results that in the total thyroidectomies performed with ultrasonically actived shears, operative time is shorter of 24 minutes compared with conventional method (81 vs 105 minutes), the mean amount of intraoperative blood loss is smaller (70 ml vs 125 ml), the postoperative pain is less, the cosmetic result is better (length of incision 6 cm vs 10 cm) and the costs is not more expensive. Complications of thyroid surgery are similar between the two methods. The use of ultrasonically actived shears in total thyroidectomy is safe (no increase of complications) and useful because it reduces operative time, improves the recovery of the patient (less pain, better cosmetic results) and, finally, is not more expensive than conventional method of haemostasis.  相似文献   
77.
A new surgical procedure for the treatment of all types of congenital blepharoptosis is described: suspension of the eyelid to the check ligament of the superior fornix. This is a dynamic suspension technique by which the check ligament, which is an extension of Tenon's capsule and normally inserts into the superior conjunctival fornix, is brought forward and sutured to the tarsus, which raises the eyelid. This technique does not sacrifice or add any tissue and is simple to repeat if necessary. Sixty-two patients were operated on using the technique and followed up for a mean of 23 months (range 3 months to 9.6 years). In a group of patients not operated on before for ptosis, 50 eyelids were raised with 74% normalisation, 22% improvement, and one eyelid each that showed only slight change or overcorrection. In a group of patients with 27 eyelids operated on before using other techniques, 67% of the eyelids were normalised, 30% were improved, and only one eyelid showed no change. In conclusion, this new technique has proved to be quite successful in raising the level of the upper eyelid in congenital blepharoptosis, with results at least comparable to those of most other techniques. The advantages with the check ligament over other techniques are the minimal trauma of the surgery, its simplicity, and its repeatability.  相似文献   
78.
79.
Although the occurrence of concomitant positive BOLD responses (PBRs) and negative BOLD responses (NBRs) to visual stimuli is increasingly investigated in neuroscience, it still lacks a definite explanation. Multimodal imaging represents a powerful tool to study the determinants of negative BOLD responses: the integration of functional Magnetic Resonance Imaging (fMRI) and electroencephalographic (EEG) recordings is especially useful, since it can give information on the neurovascular coupling underlying this complex phenomenon. In the present study, the brain response to intermittent photic stimulation (IPS) was investigated in a group of healthy subjects using simultaneous EEG‐fMRI, with the main objective to study the electrophysiological mechanisms associated with the intense NBRs elicited by IPS in extra‐striate visual cortex. The EEG analysis showed that IPS induced a desynchronization of the basal rhythm, followed by the instauration of a novel rhythm driven by the visual stimulation. The most interesting results emerged from the EEG‐informed fMRI analysis, which suggested a relationship between the neuronal rhythms at 10 and 12 Hz and the BOLD dynamics in extra‐striate visual cortex. These findings support the hypothesis that NBRs to visual stimuli may be neuronal in origin rather than reflecting pure vascular phenomena. Hum Brain Mapp 37:2247–2262, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
80.

Background

Rhinoplasty and rhinoseptoplasty are very important and complex surgical procedures because the nose plays a pivotal aesthetic role in the face and an important functional role in breathing. Mild bulbous, plunging, undefined tips are very common, and tip refining and repositioning often are required surgical procedures.

Methods

For 97 selected patients, the authors performed their personal technique consisting of a transcartilaginous approach, incomplete vertical interruption, and retrograde undermining of the lower lateral cartilages to improve tip projection and definition. The five aspects analyzed were nasal tip symmetry, nostril symmetry, tip projection, tip definition, and appearance of the nasal tip only. Each parameter was assessed using pre- and postoperative quantification according to a visual analog scale. Postoperative evaluation was performed during a mean follow-up period of 1?year.

Results

The results at 1?year showed high rates of improvement in tip definition (mean, 7.9?±?2.4) and nasal tip only evaluation (mean, 6.5?±?3.1). The patients reported an improvement in nasal tip symmetry (mean, 4.2?±?3.2), nostril symmetry (mean, 4.5?±?4.1), and tip projection (mean, 5.8?±?2.9).

Conclusions

This simple, safe, and effective technique is proposed for mild bulbous, plunging, undefined, and hypoprojected tips.  相似文献   
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