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41.
The hypothesis, a relationship between gingival tissue platelet activating factor (PAF) levels and healing after periodontal surgery, was tested by measuring PAF levels in gingival tissues collected from sites that had undergone flap surgery and guided tissue regeneration (GTR) or flap surgery alone. Using a split-mouth design, 20 intrabony defects were randomly assigned to treatment with flap surgery and GTR (group 1) or with flap surgery alone (group 2). Gingival tissue samples were obtained at surgery (baseline) and at 6-month follow-up evaluation visit. One half of each sample was used for analysis of PAF levels by high-performance liquid chromatography, and the other half of the sample was used for histomorphometric analysis that included measurements of number and diameter of blood vessels. PAF levels and diameter of blood vessels were significantly decreased (p < 0.01), and the number of blood vessels was significantly increased (p < 0.05) in both groups after 6 months compared to the baseline values. Postoperative number of blood vessels were significantly higher in group 1 (p < 0.05), whereas there was no significant difference in postoperative PAF levels between the two groups (p > 0.05). Based on the reported results, it is suggested that a decrease in gingival PAF levels might be found after conventional and regenerative periodontal surgery.  相似文献   
42.
Guided tissue regeneration is based on preventing the more rapidly proliferating epithelium from growing into the periodontal defect after surgical procedures incorporating barrier membranes. The aim of this study was to compare the proliferative activity of gingival epithelium using proliferating cell nuclear antigen (PCNA) as a marker of cell proliferation after surgical treatments with bioactive glass graft material and bioabsorbable membrane. Using split mouth design, 20 intrabony defects were randomly assigned treatments with bioactive glass (BG group) or bioabsorbable membrane (BM group). Gingival biopsies were taken at preoperative and postoperative 12 weeks. After histological processing, the number of the inflammatory cells was measured in hematoxylin and eosin-stained sections; PCNA expression was determined in immunohistochemically-stained sections. At postoperative 12 weeks, the number of the inflammatory cells was significantly decreased (p < 0.01), PCNA expression was significantly increased (p < 0.001) in both treatment groups compared to baseline data. There was no significant difference in PCNA expression between baseline values of two groups (p > 0.05), while at postoperative 12 weeks, increase in BG group was significantly greater than that in BM group (p < 0.001). These results suggest that epithelial cell proliferation is more prominent after treatment of intrabony defects with bioactive glass compared to the treatment with bioabsorbable membrane.  相似文献   
43.
The objective of this study was to determine the optimum concentrations of rainbow trout seminal plasma (RTS) supplemented extenders for goat semen quality at post-thaw and after incubation. Five sexually mature Saanen goat (Capra aegagrus hircus) were used for semen collection. Pooled semen was diluted with soybean lecithin-based extender without RTS (control) or supplemented with different concentrations of RTS (1%, 2%, 4% or 8%), at a final concentration of 150 × 106 spermatozoon/ml. Sperm motility, plasma membrane functional integrity (HOST), damaged acrosome (PSA-FITC), mitochondrial activity (rhodamine123) and DNA integrity (TUNEL) were evaluated. Spermatological parameters were evaluated at post-thaw and after 6 hr incubation. RTS8 group preserved sperm motility, acrosomal integrity, plasma membrane functional integrity and mitochondrial function better than the control group (p < .05). The study demonstrated that RTS supplemented lecithin-based extenders have useful effects on goat spermatozoa. In addition, the results of the current study represented the positive effect of using 8% RTS supplemented extender.  相似文献   
44.
Purpose

To describe a successful five-level cervical corpectomy and circumferential reconstruction in a patient with a plexiform neurofibroma causing a severe kyphotic deformity.

Methods

Case report.

Results

43-year-old man with history of Neurofibromatosis presented with signs and symptoms of myelopathy with spastic lower extremities and gait difficulties. Imaging studies demonstrated a severe kyphotic deformity of the cervical spine with associated cord compression secondary to an anteriorly positioned plexiform neurofibroma. Two-stage surgical procedure was designed to treat this lesion. Stage I consisted of tracheostomy placement, transmandibular, circumglossal approach to the anterior cervical spine, C2–C6 corpectomies, and C1–C7 reconstruction with a custom titanium cage/plate. Stage II consisted of suboccipital craniectomy, C1–C2 laminectomies, and occipital-cervical thoracic instrumented fusion (O-T8). There were no operative complications, but the patient did develop a small pulmonary embolism post-operatively treated with anticoagulation. Patient required two-weeks of inpatient rehabilitation following surgery. Gastrostomy tube and tracheostomy were successfully discontinued with preserved swallowing and respiratory function. Patient-reported outcome measurements revealed significant and sustained improvement post-operatively.

Conclusions

Five-level cervical corpectomy including C2 can be safely and successfully performed via a transmandibular, circumglossal approach. Circumferential reconstruction utilizing a custom anterior titanium cage and plate system manufactured from a pre-operative CT scan was utilized in this case. Long segment occipital-cervical-thoracic reconstruction is recommended in such a case. Using such a technique, improvement in myelopathy, correction of deformity, and improved quality of life can be achieved.

  相似文献   
45.
Background contextWound dehiscence and surgical site infections (SSIs) can have a profound impact on patients as they often require hospital readmission, additional surgical interventions, lengthy intravenous antibiotic administration, and delayed rehabilitation. Negative pressure wound therapy (NPWT) exposes the wound site to negative pressure, resulting in the improvement of blood supply, removal of excess fluid, and stimulation of cellular proliferation of granulation tissue.PurposeTo assess the incidence of wound infection and dehiscence in patients undergoing long-segment thoracolumbar fusion before and after the routine use of NPWT.Study designRetrospective study.Patient sampleOne hundred sixty patients undergoing long-segment thoracolumbar spine fusions were included in this study.Outcome measuresPostoperative incidence of wound infection and dehiscence.MethodsAll adult patients undergoing thoracolumbar fusion for spinal deformity over a 6-year period at Duke University Medical Center by the senior author (CB) were included in this study. In 2012, a categorical change was made by the senior author (CB) that included the postoperative routine use of incisional NPWT devices after primary wound closure in all long-segment spine fusions. Before 2012, NPWT was not used. After primary wound closure, a negative pressure device is contoured to the size of the incision and placed over the incision site for 3 postoperative days. We retrospectively review the first 46 cases in which NPWT was used and compared them with the immediately preceding 114 cases to assess the incidence of wound infection and dehiscence.ResultsOne hundred sixty (NPWT: 46 cases, non-NPWT: 114 cases) long-segment thoracolumbar spine fusions were performed for deformity correction. Baseline characteristics were similar between both cohorts. Compared with the non-NPWT cohort, a 50% decrease in the incidence of wound dehiscence was observed in the NPWT patient cohort (6.38% vs. 12.28%, p=.02). Similarly, compared with the non-NPWT cohort, the incidence of postoperative SSIs was significantly decreased in the NPWT cohort (10.63% vs. 14.91%, p=.04).ConclusionsRoutine use of incisional NPWT was associated with a significant reduction in the incidence of postoperative wound infection and dehiscence.  相似文献   
46.
BackgroundIncidental durotomies occur in up to 17% of spinal operations. Controversy exists regarding the short- and long-term consequences of durotomies.PurposeThe primary aim of this study was to assess the effect of incidental durotomies on the immediate postoperative complications and patient-reported outcome measures.Study designProspective study.Patient sampleA total of 1,741 patients undergoing index lumbar spine fusion were selected from a multi-institutional prospective data registry.Outcome measuresPatient-reported outcome measures used in this study included back pain (BP-Visual Analog Scale), leg pain (LP-Visual Analog Scale), and Oswestry Disability Index.MethodsA total of 1,741 patients were selected from a multi-institutional prospective data registry, who underwent primary lumbar fusion for low back pain and/or radiculopathy between January 2003 and December 2010. We collected and analyzed data on patient demographics, postoperative complications, back pain, leg pain, and functional disability over 2 years, with risk-adjusted propensity score modeling.ResultsIncidental durotomies occurred in 70 patients (4%). Compared with the control group (n=1,671), there was no significant difference in postoperative infection (p=.32), need for reoperation (p=.85), or symptomatic neurologic damage (p=.66). At 1- and 2-year follow-up, there was no difference in patient-reported outcomes of back pain (BP-Visual Analog Scale), leg pain (LP-Visual Analog Scale), or functional disability (Oswestry Disability Index) (p>.3), with results remaining consistent in the propensity-matched cohort analysis (p>.4).ConclusionWithin the context of an on-going debate on the consequences of incidental durotomy, we found no difference in neurologic symptoms, infection, reoperation, back pain, leg pain, or functional disability over a 2-year follow-up period.  相似文献   
47.
OBJECTIVE: Postural phenomena, cardiac arrhythmias and autonomic dysfunction are responsible for presyncope and syncope in patients with mitral valve prolapse (MVP). In this study, arrhythmia and vasovagal syncope incidence were investigated in children with MVP. METHODS: Between April 2005 and December 2006, 37 children with MVP and 26 healthy children were evaluated.Telecardiography, electrocardiography (ECG), echocardiography, Holter monitoring, exercise test and head-up tilt test were performed. RESULTS: The MVP group consisted of 19 boys and 18 girls with a mean age of 11.8 years. The control group was similar with respect to age and gender. Telecardiography, ECG, Holter monitoring, exercise test and QTc of all children were within normal limits.There was a statistically significant difference between the two groups in terms of QT dispersion. The tilt table test was positive in 11 of 37 (29.7%) children with MVP and in 1 of 26 (3.8%) normal healthy children. This difference was statistically significant (P < 0.01). CONCLUSION: Arrhythmia and syncope frequency was found to be higher in children with MVP than in the normal population. The risk of vasovagal syncope indicated by a positive tilt test was found to be increased in children with MVP. Therefore, patients and families must be informed about the conditions that may predispose to vasovagal syncope and caution should be recommended in these patients.  相似文献   
48.
Obstructive sleep apnea syndrome affects 0.7-3% of children and snoring is an important symptom. We aimed to evaluate the prevalence of habitual snoring and sleep-disordered breathing in primary school students in Afyonkarahisar city. There are 41 primary schools in ü? education regions in Afyonkarahisar city. One school from each region was randomly selected and all the students in that school were given a questionnaire. Of the 1100 given questionnaires 786 (71.5%) were filled in adequately and were accepted for evaluation. Of the students 407 (51.8%) were girls and 379 (48.2%) were boys. Mean age was 9.9 +/- 2.0 (7-15). The prevalence of habitual snoring was found as 4.8%. With regard to gender, occasional snoring and habitual snoring was significantly more prevalent than never snoring in boys. The prevalence of sleep disordered breathing symptoms was found to be significantly higher in habitual snorers. Maternal and paternal smoking frequency and passive smoke exposure was more common in habitual snorers but there were no significant differences among the groups. Hyperactivity symptoms were significantly higher in habitual snorers. In our study, school performance was found to be 10.9 folds lower in habitual snorers than non-snorers. We think that questioning the obstructive sleep apnea syndrome symptoms in children and performing diagnostic procedures and treatment when suspected will decrease the morbidity.  相似文献   
49.
50.
Abstract

Objective:

Primary cervical spinal tumors are rare tumors of the spine and are associated with significant morbidity and mortality. Such tumors include multiple myeloma, chordomas, giant cell tumors, hemangiomas, osteosarcomas, chondrosarcomas, synovial sarcomas, aneurysmal bone cysts (ABC), hemangiomas, eosinophilic granulomas, osteoid osteomas, and osteoblastomas. We review the surgical decision-making process and identify critical key steps for surgical complication avoidance. We also present case illustrations demonstrating such pathological diagnoses and surgical treatments performed.

Methods:

We retrospectively review the literature regarding the most common primary cervical spinal tumors that have undergone surgical resection with or without adjuvant treatment.

Results:

En bloc resection of primary cervical tumors resulted in significantly increased progression-free survival and overall survival. From the limited data, adjuvant treatment with proton-beam therapy for chordomas has potential benefit. Neo-adjuvant chemotherapy for Ewing’s sarcoma and osteogenic sarcoma has shown some promise, with en bloc resection demonstrating stronger benefit for osteogenic sarcoma.

Discussion:

En bloc resection for primary spinal tumors has proven to be the standard of care in spinal oncology. Adjuvant and neo-adjuvant treatments such as chemotherapy and radiotherapy variants (conventional, proton beam, cyberknife) need to be studied further in most primary tumor types to become standard of care. Chordoma management is more widely studied with en bloc resection and adjuvant proton-beam therapy demonstrating improved progression-free survival and overall survival. Surgical management and adjuvant treatment strategies are case dependent, depending on tumor histology, patient neurological examination, prior surgeries at that level, and prior adjuvant treatment.  相似文献   
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