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91.
BACKGROUND: Pseudoaneurysms (PsAns) of the popliteal and tibioperoneal arteries are very rare and occur as a late complication after arterial injury. This study was undertaken to describe the management of PsAns of the popliteal and tibioperoneal arteries after gunshot injuries in a civilian vascular surgical unit with a large trauma workload. METHODS: A retrospective review of the records of nine patients treated between January 1998 and November 2001 at the Thoracic and Cardiovascular Surgery Department of Numune Education and Research Hospital was undertaken. RESULTS: Nine PsAns of the popliteal and tibioperoneal arteries after gunshot injuries were treated. The delay in diagnosis from the time of injury ranged from 15 days to 14 months, with a median delay of 75 days. One case with graft occlusion was noticed in a patient with a popliteal artery PsAn. In these cases, the early and late patency rate and limb salvage were 100%. CONCLUSION: Early diagnosis of popliteal and tibioperoneal PsAns is an important factor in successful surgical reconstruction. The operative procedures will be simple if the interval between injury and operation is short, and surgical treatment for PsAns includes reconstruction of both arterial and venous arteries.  相似文献   
92.
The concurrence of ambiguous genitalia, nephropathy and predisposition to Wilms' tumor are characteristics of Denys-Drash syndrome. Some of the reported patients do not express the full spectrum of the syndrome, while the occurrence of nephropathy has become a generally accepted common feature of this syndrome. We report an infant with male pseudohermaphroditism due to partial gonadal dysgenesis and nephropathy without Wilms' tumor but with a Wilms' tumor suppressor gene (WT1) mutation. The high risk of Wilms' tumor mandates regular surveillance and the use of prophylactic bilateral nephrectomy as a treatment is not yet clear.  相似文献   
93.
OBJECTIVE: This study was undertaken to assess the left ventricular mass (LV Mass) and systolic and diastolic functions of the left ventricle in children with protein energy malnutrition (PEM). METHODOLOGY: Thirty children, aged between 2 months and 2 years with PEM (four kwashiorkor, seven marasmic- kwashiorkor, 19 marasmus), and 17 healthy, age-matched children, using Doppler echocardiography were studied. RESULTS: The mean LV Mass in the patients was lower than that in the controls (14.5 +/- 5.2 vs 19.8 +/- 4.7 g, P < 0.05). However, the LV Mass/body surface area was not different in the patients with PEM and in the control group (52 +/- 9.2 vs 53.9 +/- 8.2g/m(2), P > 0.05), indicating that LV Mass was reduced in proportion to decrease in body size in malnutrition. Left ventricular septal and posterior wall thickness in PEM were also lower than that in the controls, and the most significant reduction in the LV Mass, septal and posterior wall thickness were found in the kwashiorkor group. Cardiac output was reduced in proportion to decrease in body size in the patient group (1.6 +/- 0.5 vs 2.1 +/- 0.8 L/min, P < 0.05), therefore cardiac index was not significantly different between the patients and the control subjects (5.9 +/- 1.4 vs 5.7 +/- 1.6 L/min/m(2), P > 0.05). Systolic function indices including ejection fraction, fractional shortening, and diastolic function indices were not significantly different in the groups. CONCLUSIONS: We demonstrated that LV Mass and cardiac output were reduced in proportion to decrease in body size in patients with PEM, and LV systolic and diastolic functions were preserved in atrophic hearts.  相似文献   
94.
BACKGROUND AND AIMS: To evaluate treatment results in iatrogenic biliary injuries with concomitant vascular injuries. PATIENTS/METHODS: Between January 1998 and May 2002 (inclusive), angiography was performed in 45 of the 105 patients treated for iatrogenic biliary tract injury. The charts of these 45 patients and 5 other patients in whom vascular injury was diagnosed at operation were evaluated retrospectively. Twenty-nine patients had concomitant vascular injury, the biliovascular injury group (BVI), and the remaining 21 patients had isolated biliary tract injury (IBTI). RESULTS: The most frequent initial operation was a cholecystectomy. The frequency of high-level (Bismuth III or IV) strictures was 90% in the BVI group and 62% in the IBTI group ( P<0.05). Perioperative mortality was 7% in the BVI group and 5% in the IBTI group ( P>0.05). The morbidity in the BVI group was significantly higher ( P<0.05). Two patients in each group were lost to follow up. During a median (range) follow up of 31 months (5-51 months), a successful functional outcome was achieved in 96% of the BVI group and 100% of the IBTI group with a multimodal approach ( P>0.05). CONCLUSIONS: The frequency of high-level biliary injury and morbidity were significantly higher in the BVI group. However, concomitant vascular injury had no significant effect on mortality and medium-term outcome of biliary reconstruction. Thus, routine preoperative angiography is not recommended.  相似文献   
95.
We report our clinical experience with the newly developed Amplatzer device in transcatheter closure of nine atrial septal defects (ASDs), one ventricular septal defect (VSD), and one patent arterial duct (PDA). Eleven patients with ASD (age range 2.5-18 years) selected according to the location and size of the defect by transesophageal echocardiography (TEE), a five-year-old patient with muscular VSD and a one-year-old patient with PDA were considered for transcatheter closure with Amplatzer devices. All procedures were performed under general anesthesia with fluoroscopic and TEE guidance, following a routine hemodynamic evaluation in the catheter laboratory. The optimal device size was selected after the balloon sizing of the ASDs. The sizes of the VSD and PDA were measured on TEE and angiography. The patients were discharged at 24 hours, after an evaluation with x-ray, electrocardiogram (ECG), and echocardiography; they were on 3-5 mg/kg/day aspirin and infective endocarditis prophylaxis for six months after the procedure. They were reassessed at six to eight weeks and Holter monitoring was done in addition. Devices were used for nine ASD patients, and for the VSD and the PDA patients. Mean ASD size was 14.3 +/- 5.3 mm at TEE and 18.3 +/- 4.3 mm at balloon sizing (p=0.02). The mean size of the device was 18.7 +/- 4.2 mm. The procedure time and the fluoroscopy time were 46.1 +/- 12.3 and 12.9 +/- 1.6 minutes, respectively. Immediately after the procedure, four patients (44%) had trivial shunts (TS). TS remained in only two during discharge, and no shunt was observed at second evaluation. The devices were similarly applied to VSD (12-7 mm) and PDA (8-6 mm) patients. Both cases had TS immediately, which disappeared at 24 hours. None of the patients had major complications. Junctional rhythm developed in one patient, and another patient had frequent supraventricular extrasystoles. Amplatzer is an effective and safe device for transcatheter closure of ASD, VSD, or PDA, especially in pediatric patients.  相似文献   
96.
The laryngeal mask airway (LMA) is a new device for controlling the airway during many procedures. Aside from its use in different kinds of surgical procedures, fiberoptic flexible bronchoscopy can also be performed easily with this mask in children under sedation. This procedure was performed via LMA in 36 children (aged 2-16 years) who suffered from different kinds of respiratory diseases and were seen at Hacettepe University Ihsan Do?ramaci Children's Hospital, Pediatric Chest Disease Unit, during a seven-month period. The procedure was performed with success and no complications occurred. To the best of our knowledge, this is the first report from Turkey on flexible bronchoscopic evaluation via LMA in children with different kinds of respiratory diseases. We suggest that this technique can be used safely.  相似文献   
97.
98.
The phase change behavior of vanadium dioxide (VO2) has been widely explored in a variety of optical and photonic applications. Commonly, its optical parameters have been studied in two extreme regimes: hot (metallic) and cold (insulating) states. However, in the transition temperatures, VO2 acts like an inherent metamaterial with mixed metallic-insulating character. In this range, the portions of metallic and insulating inclusions are tuned by temperature, and therefore a gradual change of optical parameters can be achieved. In this paper, a universal hybrid modeling approach is developed to model VO2 in the intermediate region. For this aim, the measured reflectivity data, is analyzed and matched through the transfer matrix method (TMM) simulations where an effective medium theory (EMT) is employed. Based on the findings of this approach, not only the relative portions of inclusions are tailored but also their grain shapes are significantly altered in the transition range. Finally, the modeling approach is testified by experimental findings through dynamic device applications operating at short and mid infrared wavelengths. In addition, the hysteretic behaviors on electrical, optical, and structural parameters of the VO2 film along the heating and cooling cycles are demonstrated by the experiments and scrutinized by the simulations.

A universal hybrid modeling approach is developed to model VO2 in transition, revealing dynamic behavior of metallic inclusions and grain shapes.  相似文献   
99.
Transient myeloproliferative disorder (TMD) typically presents with pancytopenia, hepatosplenomegaly, and immature circulating white blood cells, and affects approximately 10 % of neonates with Down syndrome. The authors report a neonate with Down syndrome who developed acute widespread pustular eruptions as a sign of TMD. The white blood cell counts on the first day of life were markedly elevated, with blasts seen on examination of the peripheral blood smear. And the patient was noted to have a few erythematous papules and pustules especially on the face. On the following days pathergy positive crusted papules and pustules were increased and spread to trunk and extremities. Skin biopsy specimens showed pustular dermatitis, with subcorneal vesiculopustules and perivascular inflammation in superficial dermis. These lesions improved parallel with the hematologic improvement within two weeks. The authors aim to alert clinicians about this uncommon cause of vesiculopustular eruption with the present illustrative case and review the literature.  相似文献   
100.
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