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1.
Defects in the sacrococcygeal and ischial soft tissues can be treated with gluteus maximus and posterior thigh V-Y advancement flaps. However, late complications include recurrence and dehiscence of the suture line. Increasing the amount of the soft tissues over the bony prominences and multilayered closure may have an advantage for long-term durability. We modified the V-Y advancement technique by de-epithelialising the medial parts of the flap and burying them under the opposing edge of the wound or the flap. Sixteen patients with various defects of the sacrococcygeal and ischial soft tissues were operated on using this technique. All the flaps healed well with no partial or complete loss of the flap. Three patients developed complications. The main advantage of our technique is the use of healthy tissues to obliterate the dead spaces under the edges of the wound or the opposing flap. In this way, not only the defect in the skin but the defect in the subcutaneous tissue, with its iceberg tip at the surface, is treated effectively. To have an additional layer of tissue between the bone and the superficial tissues provides an extra cushion of soft tissue and avoids putting the suture line directly over the bony prominences. We used this modification safely for both unilateral and bilateral flaps. It could also be used successfully in other parts of the body.  相似文献   
2.
Reversed flaps from the forearm have been firmly established for hand coverage. Each has its own advantages and disadvantages. The reversed anterior interosseous flap is one option with special advantages in hand reconstruction. From January 2002 to July 2003 we used this flap in five consecutive male patients aged between 36 and 59. The defects were located on the first web space (2), on the dorsal side of the thumb (1), on the first metacarpal bone (1), and on the volar side of the wrist (1). Flap size was between 6 x 3 cm and 11 x 7 cm. All flaps healed without any problem and no complication was observed during the postoperative period. The major advantage of this flap is the preservation of the main arteries of the upper limb. Other advantages are as follows: good texture and colour for hand reconstruction, satisfactory rotation arc, and availability of composite and fascial flaps. Besides its advantages, the major disadvantages are unsightly donor area scar and the need for meticulous technique. As a conclusion, we found this flap very useful in hand reconstruction for coverage of small and moderate sized soft tissue defects of the hand.  相似文献   
3.
A 19-year-old immunocompetent man was admitted to hospital with diplopia, nausea, vomiting and change in mental status. The patient had a history of tuberculous meningitis that was diagnosed at another hospital 6 months before the present admission, and at that time anti-tuberculosis treatment was initiated using a first-line drug combination. A computed tomography (CT) scan of the brain revealed non-communicating hydrocephalus. A ventriculo-peritoneal shunt was inserted surgically. Two months later, the patient was hospitalized again for fever, dysphagia and left hemiparesis. At that time, his cranial CT findings were within normal limits; however, magnetic resonance imaging (MRI) revealed an irregular multilocular peripheral contrast-enhancing lesion in the posterior fossa. The abscess was surgically drained. The presence of acid-fast bacilli in the abscess material was demonstrated by Ziehl-Neelsen staining. Mycobacterium tuberculosis grew on Lowenstein-Jensen culture medium, and the strain was found to be resistant to isoniazid. One month after the operation, the patient became quadriparetic. Cervical MRI revealed a cervico-thoracic syringomyelitic cavity, after which a syringoperitoneal shunt was placed. Treatment with four drugs was continued for 10 months, and then treatment with three drugs for a total period of 18 months. The patient recovered, with residual quadriparesis. Even though very rare, isoniazid-resistant M. tuberculosis may be the causative agent of progressive tuberculosis.  相似文献   
4.
OBJECTIVES: We compared the clinical and hemodynamic results following surgical repair of traumatic brachial artery injury using two different techniques micro- and macrovascular repair. MATERIALS AND METHODS: This was a retrospective study of 27 patients who had sustained penetrating, clean cut injuries of the brachial artery. Macrovascular techniques and a saphenous vein graft was used in 13 patients, while 14 patients were treated by primary microsurgical technique. Postoperatively, patients were followed for a mean of 26 months. All patients had color Doppler examination of the brachial artery, digital artery pressures and transcutaneous oxygen saturation determined. RESULTS: Clinical results based on distal pulses, Allens test and digital pressures were similar in the two groups. Color Doppler showed 8/13 anastomotic stenoses in macrovascular vein grafted repairs and 2/14 in microvascular repairs (p<0.05). The ratio of flow velocity proximal compared distal to the injury was significantly decreased in patients who had macrovascular repairs. CONCLUSION: Using ratio between proximal and distal site of anastomosis maximal peak systolic velocity as a objective color Doppler parameter, we were able to demonstrate differences in the hemodynamic status following macrovascular repair with vein grafts and microvascular primary repair. The results emphasize the importance of using a standard repair technique for similar injuries rather than the preference of the surgeon.  相似文献   
5.
The narrowing of an extraction site often becomes problematic when attempting to restore the space with a conventional wide-diameter implant. A woman is presented who was treated with a square head, mini-dental implant-supported fixed denture for a maxillary with a narrowed edentulous area, with a mesiodistal width of 5 mm. The implant, with a diameter of 2.4 mm, was inserted without reflecting the mucoperiosteal flap and was loaded immediately. During 12 months of follow-up, there has been no bone resorption and no inflammation observed around the implant. In conclusion, in terms of both clinical and aesthetic criteria, small diameter, mini-dental implants can be successfully used as an alternative to treatment with fixed partial dentures.  相似文献   
6.
In this paper, we review optical techniques used for micro-manipulation of small particles and cells in microfluidic devices. These techniques are based on the object's interaction with focused laser light (consequential forces of scattering and gradient). Inorganic objects including polystyrene spheres and organic objects including biological cells were manipulated and switched in and between fluidic channels using these forces that can typically be generated by vertical cavity surface emitting laser (VCSEL) arrays, with only a few mW optical powers. T-, Y-, and multi-layered X fluidic channel devices were fabricated by polydimethylsiloxane (PDMS) elastomer molding of channel structures over photolithographically defined patterns using a thick negative photoresist. We have also shown that this optical manipulation technique can be extended to smaller multiple objects by using an optically trapped particle as a handle, or an optical handle. Ultimately, optical manipulation of small particles and biological cells could have applications in biomedical devices for drug discovery, cytometry and cell biology research.  相似文献   
7.
8.
Clinical and Experimental Nephrology - The kidneys are vital organs that play an important role in removing waste materials from the blood, electrolyte balance, blood pressure regulation, and red...  相似文献   
9.
OBJECTIVE: An evaluation of growth hormone (GH) testing for GH deficiency (GHD) in childhood is confounded by the lack of a world-wide consensus on the definition of GHD. Although a single GH test remains the most powerful biochemical tool in the evaluation of a child with growth failure, the test remains far from ideal. Withdrawal of somatostatin (SS) infusion is followed by a rebound rise of GH thought to be mediated by endogenous GH-releasing hormone (GHRH) function. This study was designed to compare the GH response to 90 min SS infusion in children with normal GH secretion versus children with GH deficiency. METHODS: Ten children with GHD and 10 healthy controls (NC) have been evaluated for GH response to somatostatin infusion withdrawal (SSIW) and compared with response of two provocative tests, glucagon plus propranolol test and L-Dopa test. All children received constant infusion of somatostatin for 90 min (3 microg/kg per h, Stilamin, Serono, Aubonne, Switzerland). In order to determine GH, blood samples were obtained 90 min before the SS infusion and 0, 15, 30, 45, 60, 75, and 90 min after the cessation of infusion. RESULTS: Growth hormone peak levels with SSIW were significantly lower in GH deficient children than in healthy children (2.5 +/- 1.2 ng/dL, vs 21.9 +/- 5.3 ng/dL, respectively, P < 0.01). No adverse effects were observed during or after somatostatin infusion. CONCLUSION: In the present study, SSIW elicited a significant GH rise in healthy children but not in children with GH deficiency. Although further controlled studies using more data are necessary to expand these findings, the results suggested that children with GH deficiency can be reliably discriminated from healthy children by SSIW.  相似文献   
10.
BACKGROUND: Ventilator-associated pneumonia is the leading nosocomial infection in critically ill patients. The frequency of ventilator-associated pneumonia caused by multidrug-resistant bacteria has increased in recent years, and these pathogens cause most of the deaths attributable to pneumonia. The authors, therefore, evaluated factors associated with selected multidrug-resistant ventilator-associated pneumonia in critical care patients. METHODS: The authors prospectively recorded potential risk factors at the time of intensive care unit admission. An endotracheal aspirate was obtained in all patients who met clinical criteria for pneumonia. Patients were considered to have ventilator-associated pneumonia only when they met the clinical criteria and aspirate culture was positive for bacteria 48 h or more after initiation of mechanical ventilation. Pediatric patients were excluded. Adult patients with ventilator-associated pneumonia were first grouped as "early-onset" (< 5 days) and "late-onset," determined by episodes of ventilator-associated pneumonia, and then, assigned to four groups based on the bacteria cultured from their tracheal aspirates: Pseudomonas aeruginosa, Acinetobacter baumanii, methicillin-resistant staphylococci, and all others. The first three bacteria were considered to be multidrug resistant, whereas the others were considered to be antibiotic susceptible. Potential risk factors were evaluated with use of univariate statistics and multivariate regression. RESULTS: Among 486 consecutive patients admitted during the study, 260 adults underwent mechanical ventilation for more than 48 h. Eighty-one patients (31%) experienced 99 episodes of ventilator-associated pneumonia, including Pseudomonas(33 episodes), methicillin-resistant staphylococci (17 episodes), Acinetobacter(9 episodes), and nonresistant bacteria (40 episodes). Sixty-six of these episodes were early onset and 33 episodes were late onset. Logistic regression analysis identified three factors significantly associated with early-onset ventilator-associated pneumonia caused by any one of the multidrug-resistant bacterial strains: emergency intubation (odds ratio, 6.4; 95% confidence interval, 2.0-20.2), aspiration (odds ratio, 12.7; 95% confidence interval, 2.4-64.6), and Glasgow coma score of 9 or less (odds ratio, 3.9; 95% confidence interval, 1.3-11.3). A. baumanii-related pneumonia cases were found to be significantly associated with two of these factors: aspiration (odds ratio, 14.2; 95% confidence interval, 1.5-133.8) and Glasgow coma score (odds ratio, 6.0; 95% confidence interval, 1.1-32.6). CONCLUSIONS: The authors recommend that patients undergoing emergency intubation or aspiration or who have a Glasgow coma score of 9 or less be monitored especially closely for early-onset multidrug-resistant pneumonia. The occurrence of aspiration and a Glasgow coma score of 9 or less are especially associated with pneumonia caused by A. baumanii.  相似文献   
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