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91.
OBJECTIVE: Enlargement of the ascending aorta is often combined with valvular, coronary, or other cardiac diseases. Reduction aortoplasty can be an optional therapy; however, indications regarding the diameter of aorta, the history of dilatation (poststenosis, bicuspid aortic valve), or the intraoperative management (wall excision, reduction suture, external reinforcement) are not established. METHODS: In a retrospective study between 1997 and 2005, we investigated 531 patients operated for aneurysm or ectasia of the ascending aorta (diameter: 45-76mm). Of these, in 50 patients, size-reducing ascending aortoplasty was performed. External reinforcement with a non-coated dacron prosthesis was added in order to stabilize the aortic wall. RESULTS: Aortoplasty was associated with aortic valve replacement in 47 cases (35 mechanical vs 12 biological), subvalvular myectomy in 29 cases, and CABG in 13 cases. The procedure was performed with low hospital mortality (2%) and a low postoperative morbidity. Computertomographic and echocardiographic diameters were significantly smaller after reduction (55.8+/-9mm down to 40.51+/-6.2mm (CT), p<0.002; 54.1+/-6.7mm preoperatively down to 38.7+/-7.1mm (echocardiography), p<0.002), with stable performance in long-term follow-up (mean follow-up time: 70 months). CONCLUSIONS: As demonstrated in this study, size reduction of the ascending aorta using aortoplasty with external reinforcement is a safe procedure with excellent long-term results. It is a therapeutic option in modern aortic surgery in patients with poststenotic dilatation of the aorta without impairment of the sinotubular junction of the aortic valve and root.  相似文献   
92.
We studied the kinematics of 8 ligamentous unstable elbow joint preparations after application of the Orthofix elbow external fixation device. Valgus, varus, external rotatory, and internal rotatory load tests were performed in lateral collateral ligament (LCL)-deficient and LCL/medial collateral ligament (MCL)-deficient joints. After placement of the fixator, the mean extension decreased significantly to 19.5 degrees +/- 7.2 degrees in the LCL-deficient joint and to 19.1 degrees +/- 6.6 degrees in the LCL/MCL-deficient joint compared with the mean extension of the intact joint, which was 10.5 degrees +/- 4.2 degrees. After application of the fixator, valgus displacement was significantly decreased by 4.0 degrees +/- 3.4 degrees in the LCL-deficient joint and by 3.6 degrees +/- 3.3 degrees in the LCL/MCL-deficient joint compared with the intact joint. External rotatory displacement was significantly decreased in the LCL-deficient joint by 4.9 degrees +/- 3.7 degrees and in the LCL/MCL-deficient joint by 5.0 degrees +/- 4.7 degrees. Internal rotatory displacement was significantly decreased by 3.3 degrees +/- 2.7 degrees in the LCL-deficient joint, but it was not significantly changed in the LCL/MCL-deficient joint. The Orthofix elbow external fixator guided elbow motion to a more varus position compared with the intact elbow and decreased the range of motion of the joint, constraining mainly extension. We conclude that the fixator stabilized the ligamentous unstable elbow joint efficiently but at the expense of changes in the normal motion pattern.  相似文献   
93.
de Heer J  Holst JJ 《Diabetes》2007,56(2):438-443
Glucagon-like peptide (GLP)-1 mimetics have been reported to cause hypoglycemia when combined with sulfonylureas. This study investigated the impact of tolbutamide on the glucose dependence of the GLP-1-mediated effects on insulin, glucagon, and somatostatin secretion in the in situ perfused rat pancreas. At 3 mmol/l glucose, GLP-1 alone did not augment insulin secretion, whereas tolbutamide alone caused a rapid increase in insulin secretion. However, when GLP-1 and tolbutamide were administered simultaneously, insulin secretion increased significantly to 43.7 +/- 6.2 pmol/min (means +/- SE), exceeding the sum of the responses to GLP-1 (2.0 +/- 0.6 pmol/min; P = 0.019) and tolbutamide (11.3 +/- 3.8; P = 0.005) alone by a factor of 3.3. At 11 mmol/l glucose, co-infusion of GLP-1 and tolbutamide augmented insulin secretion to 141.7 +/- 10.3 vs. 115.36 +/- 14.1 (GLP-1) and 42.5 +/- 7.3 pmol/min (tolbutamide). Interestingly, increases in somatostatin secretion, both by glucose and GLP-1, were consistently paralleled by suppression of glucagon release. In conclusion, we demonstrate uncoupling of GLP-1 from its glucose dependence by tolbutamide. This uncoupling probably explains the tendency of GLP-1 to provoke hypoglycemia in combination with sulfonylureas. The results suggest that closure of ATP-sensitive K(+) channels by glucose might be involved in the glucose dependence of GLP-1's insulinotropic effect and that somatostatin acts as a paracrine regulator of glucagon release.  相似文献   
94.
BACKGROUND: Optimal management in patients with umbilical hernias and liver cirrhosis with ascites is still under debate. The objective of this study was to compare the outcome in our series of operative versus conservative treatment of these patients. METHODS: In the period between 1990 and 2004, 34 patients with an umbilical hernia combined with liver cirrhosis and ascites were identified from our hospital database. In 17 patients, treatment consisted of elective hernia repair, and 13 were managed conservatively. Four patients underwent hernia repair during liver transplantation. RESULTS: Elective hernia repair was successful without complications and recurrence in 12 out of 17 patients. Complications occurred in 3 of these 17 patients, consisting of wound-related problems and recurrence in 4 out 17. Success rate of the initial conservative management was only 23%; hospital admittance for incarcerations occurred in 10 of 13 patients, of which 6 required hernia repair in an emergency setting. Two patients of the initially conservative managed group died from complications of the umbilical hernia. In the 4 patients that underwent hernia correction during liver transplantation, no complications occurred and 1 patient had a recurrence. CONCLUSIONS: Conservative management of umbilical hernias in patients with liver cirrhosis and ascites leads to a high rate of incarcerations with subsequent hernia repair in an emergency setting, whereas elective repair can be performed with less morbidity and is therefore advocated.  相似文献   
95.
BACKGROUND: The aim of the study was to determine the early postoperative kinetics of serum procalcitonin (PCT) levels in uncomplicated heart transplant patients under induction therapy using antithymocyte globulin (ATG). METHODS: PCT serum concentrations were measured for 7 days in 30 adult patients (26 males, 4 females, mean age 54.5 +/- 7.7 years) undergoing uncomplicated orthotopic heart transplantation. Of the 30 patients, 28 received ATG and 2 with the same immunosuppression regimen had no induction therapy. The induction therapy consisted of 100 mg/day ATG and was started 6 hours postoperatively. RESULTS: Mean PCT levels immediately before HTX were <0.3 ng/mL in both groups. After the first ATG infusion patients developed a significant (p < 0.05) elevation in PCT plasma levels without any incidence of infectious disease with peak levels up to 11.7 +/- 19.7 ng/mL on postoperative day (POD) 1. Thereafter values continuously decreased independently of further ATG administration in all patients (6.7 +/- 10.5 ng/mL on POD 3, 3.2 +/- 7.4 ng/mL on POD 5 and 1.2 +/- 3.0 ng/mL on POD 7). In the non-ATG group a mild postoperative rise in the serum PCT was observed. The values peaked on POD 2 with 2.0 +/- 1.6 ng/mL and normalized within four days. CONCLUSIONS: Perioperative administration of ATG is associated with significantly increased PCT levels even in uncomplicated heart transplant recipients. This phenomenon should not be misinterpreted as systemic infection, as systemic inflammatory reaction that seems to be induced by ATG therapy is responsible for increased PCT production.  相似文献   
96.
BACKGROUND: Minimally invasive approaches to the hip show promise of less muscle trauma compared to conventional approaches. What is the risk of damage to the superior gluteal nerve? We studied the course of the superior gluteal nerve. METHOD: 20 legs of 11 formalin-fixed Caucasian cadavers were dissected and the course and the distances of the superior gluteal nerve branches from the tip of the greater trochanter were documented. RESULTS: The branch of the gluteal superior nerve leading to the gluteal minimus muscle was 33 (20-50) mm from the tip of the greater trochanter, within a deeper layer. The nearest point of the superior gluteal nerve branches from the tip of the greater trochanter in the posterior region was 19 (10-30) mm, in the middle region 20 (20-30) mm and in the anterior region 20 (10-35) mm. In half of the cases, a distal intermuscular branch between gluteal medius and tensor fasciae latae muscle could be found, mean 27 (10-40) mm caudal and 38 (25-60) mm ventral to the tip of the greater trochanter. This distal branch is considered to create a loop with upper branches of the superior gluteal nerve within the tensor fasciae muscle. INTERPRETATION: The safe zone for the superior gluteal nerve was smaller than previously reported. Use of a minimal direct lateral approach puts the inferior branches within the gluteal medius at risk; however, a minimal anterolateral approach to the hip may compromise branches of the superior gluteal nerve to the tensor fasciae latae muscle.  相似文献   
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99.

Background

For patients with merkel cell carcinoma (MCC), the status of regional lymph nodes at presentation is the single most important prognosticating tool, and the procedure is used for managing MCC patients with early stage disease identifying regional nodal micrometastasis.

Methods

A retrospective study was conducted of MCC patients treated at the University Hospital of Aarhus, Denmark, between 1998 and 2013. Outcomes of interest included the time and type of first recurrence after first treatment. In 2010, our institution began using sentinel lymph node biopsy (SLNB) for MCC patients with clinically early stage disease.

Results

Thirty four patients were identified, 61.8 % of the patients presented with stage I disease, 21.5 % with stage II, 11.8 % with stage III and 5.9 % with stage IV. Thirteen patients (38.2 %) had disease recurrence, with local recurrence in three patients, regional recurrence in seven patients and distant recurrence in three patients. Median length of follow-up for all patients was 14.5 months (range 0–86). Since 2010, SLNB has been performed in seven patients; all with negative sentinel lymph nodes (SLN). Three patients had tumour located to the head and neck, three patients to the extremities and one patient to the truncus. Nodal recurrence developed in one of these patients after 5.9 months.

Conclusions

The majority of patients develop recurrence within the first 2 years after initial treatment, most representing with nodal metastasis. The introduction of SLNB may hopefully detect nodal involvement in an early stage, improving the outcome for patients with MCC. Level of Evidence: Level IV, risk/prognostic study.  相似文献   
100.
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