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991.
992.
Functional reconstruction of the anterior mandibular defect in combination with a significant glossectomy is a challenging problem for reconstructive micro‐surgeons. In this retrospective study, clinical results were compared between mandibular reconstruction plate (MRP) procedures and double flap transfers. The subjects were 23 patients who underwent immediate reconstruction, after an anterior segmental mandibulectomy in combination with a significant glossectomy, from 1993 to 2009. The patients were divided into two groups based on the reconstructive methods used: MRP and soft tissue free flap transfer (MRP group: 12 patients) or double free flap transfer (double flap group: 11 patients). Operative stress, postoperative complications and oral intake ability were compared between the groups. The rate of recipient‐site complication in the double flap group tended to be lower than that in the MRP group. The most frequent complications in the MRP group included infection and orocutaneous fistula. Operative stresses (operation time and blood loss) were significantly less in the MRP group than in the double flap group. Overall, 19 patients (82.6%) were able to tolerate an oral diet without the need for tube feeding. This study demonstrates that laryngeal preservation is possible in more than 80% of patients even after such an extensive ablation. Double flap transfer provides a more stable wound closure than MRP and should be the preferred reconstructive procedure if the patients can tolerate the associated operative stresses. © 2012 Wiley Periodicals, Inc. Microsurgery, 2012.  相似文献   
993.
Mongolian spots are congenital and confluent hyperpigmented areas that are usually grayish blue in color. They are found most frequently in the sacral region in infants and typically disappear during childhood. Occasionally, they persist to adulthood. We retrospectively examined outcomes of laser treatment of persistent Mongolian spots. We used Q-switched alexandrite laser to treat persistent Mongolian spots of 16 Japanese patients at 14?years old or older. A good therapeutic outcome was achieved overall; however, postinflammatory hyperpigmentation and hypopigmentation were observed in two patients, respectively. While laser treatment was effective for all seven patients with extrasacral Mongolian spots, four out of ten patients with sacral Mongolian spots were refractory to treatment. Of these patients, two received laser irradiation only twice and abandoned treatment, simply because of unsatisfactory results without any adverse events. The other two patients received treatments at intervals of 3?months, which resulted in postinflammatory hyperpigmentation. Contrary to children, who generally show good response after two or three sessions of irradiation, we should consider more frequent irradiation, longer intervals between treatment sessions, and use of bleaching creams in the treatment of persistent sacral Mongolian spots in adults.  相似文献   
994.
The authors reported a subclavian artery stenting (SAS) using gadolinium contrast medium. The patient was a 65-year-old female who presented dizziness and right upper extremity pain with movement. Digital subtraction angiography revealed right subclavian artery occlusion with subclavian steal phenomenon. We tried to treat this lesion using SAS. However, iodinated contrast medium caused the allergy in this patient and the treatment was discontinued. Therefore, SAS was performed with gadolinium contrast medium. Using gadolinium contrast medium, it is possible to confirm large arteries like innominate artery and subclavian artery. The stenting procedure was performed without complication. The usage of gadolinium contrast medium has the limit and some strategies are important to reduce the usage of gadolinium contrast medium in SAS. First, PercuSurge GuardWire? was placed in the right internal carotid artery to confirm the anatomy, to decide working angle, and to treat the common carotid artery in case of dissection. Second, a "U" shaped guide wire was placed in the distal end from the brachial artery. Guide wire from femoral side was able to pass the lesion at midpoint of the "U" shaped one. SAS using gadolinium contrast medium may be an alternative treatment if a patient with subclavian artery stenosis or occlusion is allergic to iodinated contrast medium.  相似文献   
995.
There have been few reports regarding the efficacy of posterior instrumentation alone as surgical treatment for patients with pyogenic spondylitis, thus avoiding the morbidity of anterior surgery. We report the clinical outcomes of six patients with pyogenic spondylitis treated effectively with a single-stage posterior fusion without anterior debridement at a mean follow-up of 2.8 years (2 to 5). Haematological data, including white cell count and level of C-reactive protein, returned to normal in all patients at a mean of 8.2 weeks (7 to 9) after the posterior fusion. Rigid bony fusion between the infected vertebrae was observed in five patients at a mean of 6.3 months (4.5 to 8) post-operatively, with the remaining patient having partial union. Severe back pain was immediately reduced following surgery and the activities of daily living showed a marked improvement. Methicillin-resistant Staphylococcus aureus was detected as the causative organism in four patients. Single-stage posterior fusion may be effective in patients with pyogenic spondylitis who have relatively minor bony destruction.  相似文献   
996.
A non-functioning paraganglioma is usually benign, however, it may cause distant metastases. There is no histological appearance for the diagnosis of malignancy or absolute criteria for predicting malignant potential. Bony metastases from paraganglioma are known to occur, but, skull metastases are very rare. We report a case of intracranial metastases from a renal paraganglioma. A 61-year-old male presented with temporal headache and exophthalmos on the left side. Seven years prior, he underwent surgery to remove a mass in the right renal hilum, which was diagnosed as renal cell carcinoma at that time. Computed tomography and magnetic resonance imaging showed a ring-like enhanced mass in the left middle fossa, which destroyed the sphenoid bone and the lateral wall of the orbit. Another osteolytic lesion was revealed in the occipital bone. The fragile tumor was totally resected. Histopathological study revealed the Zellballen pattern with extensive coagulation necrosis. No apparent nuclear atypia or mitosis were present. Immunohistochemistry showed reactivity for synaptophysin and chromogranin A in the tumor cells. Review of the surgical specimen of the previously resected renal tumor revealed the same pathological and immunohistochemical findings as those of chief cells in the middle fossa tumor. Thus, this tumor was diagnosed as a malignant paraganglioma metastasized from renal paraganglioma. After six cycle chemotherapy with cyclophosphamide and vincristine, his condition was stable for two years, however, he died four years after the diagnosis of malignancy.  相似文献   
997.
A 32-year-old Filipino female presented with Takayasu's arteritis manifesting as an abrupt onset of syncope. Physical examination revealed diminished consciousness, right hemiparesis, and a large discrepancy in blood pressure between the upper and lower extremities. Magnetic resonance imaging revealed cerebral infarcts in the left basal ganglia and the left temporal lobe. Angiography revealed complete occlusion of the left common carotid artery and severe stenosis of the brachiocephalic artery, the right common carotid artery, and the left subclavian artery. Based on the clinical examination and studies, the diagnosis was Takayasu's arteritis, type I. The patient's condition stabilized after 2 months of prednisone and anti-platelet therapy. Single stage multiple stenting in the brachiocephalic artery, the right common carotid artery, and the left subclavian artery was then performed using high pressure inflation to dilate the arteries due to the remarkably rigid lesions that resulted from extensive and diffuse fibrosis throughout the vessel walls. Although a small intimal flap occurred during inflation of the left subclavian artery, re-dilation was possible with the stent. Even with evidence of notable recovery in blood pressure and cerebral blood flow, no further neurological improvement was observed. In view of the favorable short- and intermediate-term results, single stage multiple stenting may be the optimum treatment option for first-line stent-supported angioplasty in patients with Takayasu's arteritis.  相似文献   
998.
Desmosterolosis is an autosomal recessive disease caused by mutations in the 3β-hydroxysterol-Delta24 reductase (DHCR24) gene, with severe developmental anomalies including short limbs. We utilized DHCR24 knockout (KO) mice to study the underlying bone pathology. Because the KO mice died within a few hours after birth, we cultured metatarsal bones from newborn mice. The growth of bones from KO mice was significantly retarded after 1 week of culture. Absence of proliferating chondrocytes in the growth plate and abnormal hypertrophy of prehypertrophic chondrocytes were observed in the bones from KO mice. Hypertrophic differentiation was evidenced by higher expression of Indian hedgehog, alkaline phosphatase, and matrix metalloproteinase 13. Since elevated levels of reactive oxygen species (ROS) during chondrogenesis are known to inhibit proliferation and to initiate chondrocyte hypertrophy in the growth plate, and since DHCR24 acts as a potent ROS scavenger, we hypothesized that the abnormal chondrocyte proliferation and differentiation in KO mice were due to decreased ROS scavenging activity. Treatment with an antioxidant, N-acetyl cysteine, could correct the abnormalities observed in the bones from KO mice. Treatment of bones from wild-type mice with U18666A, a chemical inhibitor of DHCR24, resulted in short broad bones with a disrupted proliferating zone. Treatment of ATDC cells with hydrogen peroxide (H2O2) induced hypertrophic changes as evidenced by the expression of the marker genes specific for hypertrophic chondrocyte differentiation. H2O2-induced hypertrophic change was prevented by adenoviral delivery of DHCR24. Induction of chondrocyte differentiation in ATDC cells by insulin was associated with increased ROS production that was markedly enhanced by treatment of ATDC5 cells with DHCR24 siRNA. This is the first demonstration that DHCR24 plays an important role in long bone growth by protecting chondrocytes from ROS  相似文献   
999.
1000.
BackgroundImmune checkpoint inhibitors (ICIs) are increasingly being used for the treatment of upper gastrointestinal cancers [esophageal cancer and gastric cancer (GC)]. They cause imbalances in immunological tolerance, resulting in immune-related adverse events (irAEs). Although irAEs have been reported to be associated with the efficacy of ICIs in some cancers, the relationship between irAEs and prognosis of upper gastrointestinal cancers remains unknown. This study aimed to investigate the prognostic impact of irAEs in patients with advanced or recurrent upper gastrointestinal cancer treated with nivolumab.MethodsWe retrospectively divided the patients (n=96) who received nivolumab into two groups: the irAEs group (n=41) and non-irAEs group (n=55), according to the Common Terminology Criteria for Adverse Events ver. 5.0.ResultsirAEs were significantly associated with good performance status and high serum albumin levels (all P<0.05). The irAEs group had a significantly longer overall survival (OS) than the non-irAEs group [log-rank P=0.003; univariate hazard ratio (HR) =0.36, 95% confidence interval (CI) =0.21–0.65, P<0.01; multivariate HR =0.47, 95% CI =0.26–0.88, P=0.018]. Importantly, in both esophageal cancer and GC, the irAEs group experienced favorable clinical outcomes compared with the non-irAEs group. In the multivariate analysis, male sex (P<0.01), presence of irAEs (P=0.018), and good pretreatment performance status (P<0.01) were independent prognostic factors.ConclusionsAmong patients with upper gastrointestinal cancer treated with nivolumab, the prognosis of patients who developed irAEs was better than that of patients who did not develop irAEs. Long-term continuation of nivolumab by early detection of irAEs and an appropriate response to irAEs are important.  相似文献   
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