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71.
We describe emergency airway management with fiberoptic intubation in a patient in the prone position with her neck flexed by a head pin holder during a neurosurgical procedure. Laryngeal mask airway is suggested in emergency difficult airway algorithms; however, this was not feasible in this patient because of her edematous upper airway and limited mouth opening resulting from extreme neck flexion by a head pin holder. The case illustrates the role of fiberoptic intubation in emergency airway management in this critical situation. Maneuvers to facilitate fiberoptic technique are also described.  相似文献   
72.
BACKGROUND: Elimination of abnormally high joint-loading resulting in excessive contact stresses may prevent or reduce the onset of osteoarthrosis in a dysplastic hip. A number of periacetabular osteotomies have been shown to be effective in restoring normal hip-joint mechanics. We treat acetabular dysplasia with a periacetabular osteotomy performed through a modified Ollier transtrochanteric approach. In this report, we describe the operative technique and the clinical and radiographic results. METHODS: Thirty-six patients (thirty-eight hips) in whom a painful dysplastic hip had been treated with a periacetabular osteotomy between March 1991 and June 1999 were included in the study. There were thirty-five female patients and one male patient with a mean age (and standard deviation) at the operation of 29.42 +/- 9.1 years. The technique utilizes a u-shaped skin incision, and a routine osteotomy of the greater trochanter with distal transfer if needed, and allows excellent visualization enabling the surgeon to perform the periacetabular osteotomy without penetrating the joint. RESULTS: At a mean of five years and six months postoperatively, the mean modified Harris hip score had improved from 59.1 +/- 15.8 points preoperatively to 87.97 +/- 14.3 points. Radiographically, the degree of osteoarthrosis had decreased in eleven hips, remained unchanged in twenty-four, and worsened in three. The mean anterior center-edge angle had increased from 22.0 degrees +/- 12.9 degrees to 36.1 degrees +/- 12.3 degrees, the mean lateral center-edge angle had increased from -2.7 degrees +/- 14.4 degrees to 26.6 degrees +/- 14.1 degrees, the mean acetabular index angle had improved from 23.4 degrees +/- 6.6 degrees to 12.7 degrees +/- 4.6 degrees, and the mean acetabular head index had increased from 48.2% +/- 12.7% to 73.1% +/- 16.0%. The Shenton line was restored in eleven hips. Thirty patients (thirty-two hips; 84%) had a satisfactory result. A poor preoperative functional score was associated with an unsatisfactory outcome (p = 0.00191). Complications included prolonged limping (eleven hips); numbness in the distribution of the lateral femoral cutaneous nerve (four); osteonecrosis of the rotated acetabular fragment (two); and acetabulofemoral impingement, heterotopic ossification, and a defect on the rotated ilium (one hip each). CONCLUSIONS: Painful dysplastic hips should be treated before function becomes seriously impaired. We believe that periacetabular osteotomy through a modified Ollier approach, which allows osseous cuts to be made under direct vision, can be learned readily. It provides improved femoral head coverage and relief of symptoms in most painful dysplastic hips in adolescents and young adults.  相似文献   
73.
Recently, we have proposed a model for the development of ovarian surface epithelial tumors. In this model, all histologic types of surface epithelial tumors are divided into 2 categories designated type I and type II which correspond to 2 pathways of tumorigenesis. Type I tumors include low-grade serous carcinoma, mucinous carcinoma, endometrioid carcinoma, malignant Brenner tumor, and clear cell carcinoma which develop slowly in a stepwise fashion from well-recognized precursors, namely atypical proliferative (borderline) tumors. Type II tumors are high-grade, rapidly growing tumors that typically have spread beyond the ovaries at presentation. They include high-grade serous carcinoma ("moderately" and "poorly" differentiated), malignant mixed mesodermal tumors (carcinosarcomas), and undifferentiated carcinoma. These tumors are rarely associated with morphologically recognizable precursor lesions and it has been proposed that they develop "de novo" from ovarian inclusion cysts. This model implies that the pathogenesis of type I and type II tumors are separate and independent but it is not clear whether some type II tumors develop from type I tumors. In this study, we attempted to address this issue by determining the clonality of 6 cases of high-grade serous carcinomas that were closely associated with atypical proliferative serous (borderline) tumors and invasive low-grade micropapillary serous carcinomas. We reviewed 210 ovarian serous tumors from the surgical pathology files of the Johns Hopkins Hospital and identified 3 high-grade serous carcinoma that were directly associated with atypical proliferative serous (borderline) tumors and 3 that were associated with invasive low-grade micropapillary serous carcinomas. A morphologic continuum between the high-grade carcinoma and the low-grade tumors was observed in 4 cases whereas in the remaining 2 cases the high-grade and low-grade components were separate. Mutational analyses for KRAS, BRAF, and p53 genes were performed on microdissected samples from the high-grade and low-grade tumor areas for each case. All 6 tumors demonstrated wild-type BRAF and p53 genes. Only 2 of the 6 cases were informative from a molecular genetic standpoint. In those 2 cases we found the same mutations of KRAS in both the atypical proliferative serous (borderline) tumor and the high-grade serous carcinoma component of the tumor, indicating a clonal relationship. The above results suggest that the majority of high-grade and low-grade carcinomas develop independently but in rare cases, a high-grade serous carcinoma may arise from an atypical proliferative serous (borderline) tumor.  相似文献   
74.
Keloids are locally aggressive scars that typically invade into healthy surrounding skin and cause both physical and psychosocial distress to the patient. These pathological scars occur following minimal skin trauma after a variety of causes including burns and trauma. Although the pathogenesis of keloid disease is not well understood, it is considered to be the end product of an abnormal healing process. The aim of this review was to investigate the molecular and cellular pathobiology of keloid disease in relation to the normal wound healing process. The molecular aberrances in keloids that correlate with the molecular mechanisms in normal wound healing can be categorized into three groups: (1) extracellular matrix proteins and their degradation, (2) cytokines and growth factors, and (3) apoptotic pathways. With respect to cellular involvements, fibroblasts are the most well‐studied cell population. However, it is unclear whether the fibroblast is the causative cell; they are modulated by other cell populations in wound repair, such as keratinocytes and macrophages. This review presents a detailed account of individual phases of the healing process and how they may potentially be implicated in aberrant raised scar formation, which may help in clarifying the mechanisms involved in keloid disease pathogenesis.  相似文献   
75.
BACKGROUND: The purpose of this report is to present long-term outcomes of gamma knife radiosurgery for intracranial mature teratoma after debulking surgery. METHODS: Three patients with intracranial mature teratoma had initial target volumes of 5.4, 18.7, and 5.1 cm(3), respectively, and were treated by gamma knife radiosurgery between 1993 and 2004. Marginal doses of 17, 12.5, and 13.5 Gy, respectively, were delivered to the tumors at isodose levels of 50%, 50%, and 62%, respectively. The first patient received radiosurgery after surgical removal and conventional radiotherapy. The second patient received similar management, including surgery and radiotherapy, with tumor recurrence. Two additional operations and subsequent radiosurgery were performed on this patient. Based on the favorable results of the first 2 patients, we performed radiosurgery instead of conventional radiotherapy after subtotal surgical removal in the last patient. By reviewing literatures concerning the therapeutic modalities and the long-term results of our 3 patients, we discuss the role of radiosurgery in treating intracranial mature teratoma. RESULTS: A follow-up period of 121, 89, and 31 months, respectively, demonstrated tumor volume reduction rates of 70%, 89%, and 48%, respectively. No evidence of further tumor progression and no radiosurgery-related complication or morbidity was noted. The school performances of the affected children are all above average. CONCLUSIONS: Gamma knife radiosurgery provides a safe and effective alternative as the adjuvant treatment of intracranial mature teratoma after surgical debulking. Previous conventional radiotherapy does not alter final tumor control. Radiosurgery should be considered when residual tumor growth continues with no related symptoms or evaluations of tumor markers during follow-up.  相似文献   
76.
PURPOSE: To analyze magnetic resonance (MR) patterns of fractures and pseudoarthrosis of the ankylosing spondylitic spine, and related changes in the dura and adjacent soft tissue. MATERIALS AND METHODS: Sixteen patients with radiographically evident fractures or pseudoarthrosis of the spine were included. Each underwent MR studies. Ten patients among them underwent surgical operations. RESULTS: Both transdiscal (n = 12) and transvertebral (n = 4) fractures were identified. The levels were located from T9 to L3. Five of 16 patients had pseudoarthrosis. The fractures or pseudoarthrosis had two patterns: low signal on T1-and high signal on T2-weighted images, and low signal on both T1-and T2-weighted images. Disruption of anterior longitudinal ligament (ALL) was identified in 14 patients. Seven patients had vertebral translation, all had disruption of the ALL. Dural adhesions were noted in five patients and manifested as linear epidural enhancements with triangular blunt edges. CONCLUSION: MR patterns of ankylosing spondylitis are important in evaluating complications of fractures or pseudoarthrosis, as well as changes in dura, soft tissue, and ligaments.  相似文献   
77.
Plasmapheresis not only removes circulating antibodies but also modulates cellular immunity, including lymphocyte subsets. To investigate the effect of double‐filtration plasmapheresis (DFPP) on the ratio of lymphocyte subsets in patients with myasthenia gravis (MG), we examined the percentages of B‐cells, T‐cells, T helper (Th) cells, T suppressor (Ts) cells, natural killer (NK) cells, NKT cells, and Th/Ts ratio before and after a single DFPP session and after a course of DFPP. A total of 26 patients were recruited; their peripheral blood lymphocyte subsets were assayed using flow cytometry. After a single session of DFPP treatment, the percentages of T‐cells (P = 0.0200), Th cells (P = 0.0178), and the Th/Ts ratio (P = 0.0309) decreased significantly, whereas the percentage of NK cells (P = 0.0007) increased significantly. More importantly, after one course of DFPP treatment, the reduced clinical quantitative MG (QMG) score was correlated with the decrease of the percentage of T‐cells (r = 0.5005, P = 0.0092). Fourteen thymectomized MG patients had decreased percentages of T‐cells (P = 0.0304) and Th cells (P = 0.0444), whereas they had increased NK cells (P = 0.0197) after a single DFPP session. Here, transiently decreased percentages of T‐cells after the full DFPP course could enhance the effectiveness of plasmapheresis for MG patients.  相似文献   
78.
Metabolic adaptation of the chick embryo to chronic hypoxia   总被引:1,自引:0,他引:1  
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79.
80.
PURPOSE: To explore whether insulin resistance and beta-cell dysfunction are both related to diabetic retinopathy (DR) in type II diabetics by using a community-based study in Kinmen, Taiwan. METHODS: A screening program for DR was performed by a panel of ophthalmologists who used ophthalmoscopy and 45 degrees color retinal photographs on dilated pupils to determine a consensus grade of diabetic retinopathy. Screening, which was conducted between 1999 and 2002, involved 971 patients diagnosed with type II diabetes. The Homeostatis Model Assessment (HOMA) method was used to determine insulin resistance and beta-cell dysfunction. RESULTS: Seven hundred twenty-five diabetics who attended ophthalmological fundus checkups were studied. The overall response rate was 75%. After excluding 10 insulin-treated diabetics, diabetic retinopathy at first eye screening among the remaining 715 diabetics was 18.5%. Based on the multiple logistic regression, DR was found to be strongly related to both baseline insulin resistance (IR) and beta-cell dysfunction regardless of duration of diabetes. The strength of the relationships was maintained after adjustment for confounders. Those who were in the 2nd, 3rd, and 4th quartile of HOMA IR had 1.38 times (95% CI: 0.62-3.05), 2.37 times (95% CI: 1.19-4.69), and 4.16 times (95% CI: 2.15-8.06) the risk for DR compared to that in the 1st quartile, respectively. A reduced risk for DR in relation to HOMA beta-cell dysfunction for the 2nd, 3rd, and 4th quartile were 64% (95% CI: 27%-82%), 82% (95% CI: 58%-92%), and 82% (95% CI: 60%-92%) compared to that in the 1st quartile, respectively. CONCLUSIONS: Insulin resistance and beta-cell dysfunction are both associated with diabetic retinopathy in type II diabetes.  相似文献   
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