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61.
OBJECTIVE: This paper presents our experience with gunshot wounds to the temporal bone and discusses facial nerve lesions, surgical indication, surgical timing, and other findings. STUDY DESIGN: We performed a retrospective review of patients treated for facial nerve lesion after gunshot injury to the temporal bone. SETTING: The study was performed in the Otolaryngology Department of the University of Sao Paulo Medical School, Sao Paulo, Brazil. PATIENTS: Ninety-eight patients treated between 1988 and 1999 were analyzed. INTERVENTION: Facial nerve lesions, bullet locations, and surgical techniques were analyzed. Patients were monitored for 2 years. RESULTS: Gunshot trauma to the temporal bone presented considerable tissue loss resulting from the abrasion effect and severity of the impact. The third segment of the facial nerve was most affected, and the bullet was typically found lodged in the mastoid tip. Postoperative infection was common. Such cases required revision surgery, resulting in worse cosmetic outcomes than in cases of closed trauma. CONCLUSIONS: Surgical exploration of the facial nerve should be performed as soon as possible, since long delays increase the chance of traumatic neuroma and more pronounced scarring around the facial nerve. Open mastoidectomy with meatoplasty is the surgical technique recommended for repairing the mastoid and the facial nerve. In the majority of cases, a cable graft is necessary. Since nerve lesion in proximity to the stylomastoid foramen and extratemporal facial nerve is common, these areas must be explored carefully.  相似文献   
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Colorectal cancer (CRC) is found among those with greatest frequency and exponential increase worldwide, with high mortality rates, which are observed as increasing due to the postsurgical complications that come to present. Systemic inflammation participates in the development and progression of cancer; therefore, inflammatory and/or immunological response markers such as the neutrophil/lymphocyte index (NLI) can aid us in predicting the poor results of our interventions. The purpose of our study was to determine the impact of an NLI of ≥2.6 as a predictor of early postsurgical complications. By means of a prospective cohort, we analyzed 158 patients with CRC who were submitted to elective surgery with a later 30-day follow-up. We found that the preoperatory NLI of ≥2.6 obtained an odds ratio (OR) = 2.24 (95% confidence interval [CI], 1.15-4.36) as a prognostic factor of early postsurgical complications according to the Clavien-Dindo classification scale, which represents a low prognostic impact due to its predictive yield with low accuracy, which is the opposite of what other reports have previously published. The use of chemotherapy before the surgical procedure was also determined to be a risk factor for post-surgical complications.  相似文献   
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Titanium oxide (TiO2) has been widely investigated as a photocatalytic material, and the fact that its performance depends on its crystalline structure motivates further research on the relationship between preparation methods and material properties. In this work, TiO2 thin films were grown on non-functionalized wave-like patterned vertically aligned carbon nanotubes (w-VA-CNTs) via the atomic layer deposition (ALD) technique. Grazing incidence X-ray diffraction (GIXRD) analysis revealed that the structure of the TiO2/VA-CNT nanocomposites varied from amorphous to a crystalline phase with increasing deposition temperature, suggesting a “critical deposition temperature” for the anatase crystalline phase formation. On the other hand, scanning transmission electron microscopy (STEM) studies revealed that the non-functionalized carbon nanotubes were conformally and homogeneously coated with TiO2, forming a nanocomposite while preserving the morphology of the nanotubes. X-ray photoelectron spectroscopy (XPS) provided information about the surface chemistry and stoichiometry of TiO2. The photodegradation experiments under ultraviolet (UV) light on a model pollutant (Rhodamine B, RhB) revealed that the nanocomposite comprised of anatase crystalline TiO2 grown at 200 °C (11.2 nm thickness) presented the highest degradation efficiency viz 55% with an illumination time of 240 min. Furthermore, its recyclability was also demonstrated for multiple cycles, showing good recovery and potential for practical applications.

Amorphous or anatase crystalline TiO2/VA-CNT nanocomposites were grown controlling the synthesis temperature. Photocatalytic degradation of RhB of 55% was achieved after 240 min. The immobilized material remains active after 4 cycles of use.  相似文献   
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We wished to verify whether semen processing by discontinuous double-layered density gradient centrifugation could improve sperm apoptotic DNA fragmentation rates using a commercially available deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling assay in 35 consecutive men presenting for assisted reproductive treatments. Although sperm motility did improve as expected, no effects were observed in sperm apoptotic DNA fragmentation rates, and this should be considered in the routine assisted reproduction setting.  相似文献   
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