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71.
A 73-year-old man on dialysis for chronic renal dysfunction was referred to our hospital for surgical treatment of an abdominal aortic aneurysm (AAA). Preoperative angiography showed a remarkably developed meandering artery branching from the inferior mesenteric artery (IMA). The superior mesenteric and celiac arteries were occluded at the origin, and all blood flow to the abdominal organs was apparently supplied by collateral circulation from the IMA. Considering the risk of mesenteric ischemia after aortic clamping in conjunction during surgery, we used a perfusion catheter with a 12-F balloon to create a shunt to the IMA from the subclavian artery. The operation was successful and the patient recovered uneventfully. We describe this surgical procedure for its effectiveness in preventing postoperative mesenteric ischemia in a rare case of an AAA with complex branching lesions.  相似文献   
72.
LRRK2 G2019S is the most common known cause of Parkinson disease (PD) in patients of European origin, but little is known about its distribution in other populations. The authors identified two of 586 Japanese patients with PD heterozygous for the mutation who shared a haplotype distinct from that observed in Europeans. This suggests that G2019S originated from separate founders in Europe and Japan and is more widely dispersed than previously recognized.  相似文献   
73.
We report two cases of aortic valve replacement (AVR) for severe aortic stenosis (AS) before the cancer operations. Severe AS poses a great risk for noncardiac surgery. In the ACC/AHA 2007 Guideline on Perioperative Cardiovascular Evaluation and Care for Noncardiac Surgery, if the AS is symptomatic, elective noncardiac surgery should generally be postponed or canceled. Such patients require AVR before elective noncardiac surgery. On the other hand, in patients with severe AS who refuse cardiac surgery, noncardiac surgery can be performed with a mortality risk of approximately 10%. In our cases, severe AS was found in the preoperative examination. We informed them about necessary AVR before noncardiac surgery, and patients consented to our suggestion. AVR was performed around 7 days after this consent, and cancer operation was performed around 30 days after the AVR. However, there are no clear guidelines for this interval between AVR and cancer operation. In our cases the patients underwent the cardiac surgery and noncardiac surgery in a short period without serious complication in the perioperative management. It is very important to discuss among surgeon, cardiovascular surgeon, cardiologist and anesthesiologist. Especially anesthesiologist should take an important role in organizing these departments for such patients.  相似文献   
74.
We reviewed 75 patients (57 men and 18 women), who had undergone tension-band laminoplasty for cervical spondylotic myelopathy (42 patients) or compression myelopathy due to ossification of the posterior longitudinal ligament (33 patients) and had been followed for more than ten years. Clinical and functional results were estimated using the Japanese Orthopaedic Association score. The rate of recovery and the level of postoperative axial neck pain were also recorded. The pre- and post-operative alignment of the cervical spine (Ishihara curve index indicating lordosis of the cervical spine) and the range of movement (ROM) of the cervical spine were also measured. The mean rate of recovery of the Japanese Orthopaedic Association score at final follow-up was 52.1% (SD 24.6) and significant axial pain was reported by 19 patients (25.3%). Axial pain was reported more frequently in patients with ossification of the posterior longitudinal ligament than in those with cervical spondylotic myelopathy (p = 0.027). A kyphotic deformity was not seen post-operatively in any patient. The mean ROM decreased post-operatively from 32.8° (SD 12.3) to 16.2° (SD 12.3) (p < 0.001). The mean ROM ratio was 46.9% (SD 28.1) for all the patients. The mean ROM ratio was lower in patients with ossification of the posterior longitudinal ligament than in those with cervical spondylotic myelopathy (p < 0.001). Compared to those with cervical spondylotic myelopathy, patients with ossification of the posterior longitudinal ligament had less ROM and more post-operative axial neck pain.  相似文献   
75.
PURPOSE: Both mucin-producing carcinomas and nabothian cysts in the cervix show very high signal intensity on T2-weighted images (WI). The purpose of this study was to evaluate the potential of MR imaging in differentiating mucin-producing carcinomas from nabothian cysts. MATERIALS AND METHODS: Forty-six patients who underwent hysterectomy and had very high signal intensity lesions in the uterine cervix on T2-WI were included in this study. The pathological diagnoses were mucin-producing carcinoma in 13 patients, non-mucin-producing carcinoma accompanied with nabothian cyst in four patients, and nabothian cyst in 29 patients. T1-WI, T2-WI, and Gd-T1-WI were obtained in all patients. Malignancies were diagnosed on Gd-T1-WI as follows: (1) an enhanced lesion, (2) an irregular margin, (3) iso-intensity on T1-WI. In contrast, high signal intensity on T1-WI was considered benign. RESULTS: Thirteen of 17 malignant lesions and three of 29 benign lesions were enhanced. Irregular margins were observed in 12 of 17 malignant lesions and four of 29 benign lesions. Nineteen benign lesions and seven malignant lesions demonstrated high signal intensity on supplemental T1-WI. Combining the lesion criteria of enhancement, irregular lesion margin, and iso-intensity on T1-WI, the overall accuracy, sensitivity, and specificity rates of diagnosing malignancy were 89%, 88%, and 90%, respectively (p < 0.01). CONCLUSION: MR imaging accurately differentiated mucin-producing carcinomas from nabothian cysts that showed high signal intensity on T2-WI in the cervical stroma. For diagnosing mucin-producing carcinomas and nabothian cysts when signal intensity was remarkably high on T2-WI, Gd-T1-WI findings provided key information for differentiation, and T1-WI was useful for improving specificity.  相似文献   
76.
PURPOSE: To clarify whether processed digital chest radiography can improve the detection rate for small peripheral lung cancer. MATERIAL AND METHODS: Five radiologists independently interpreted 54 digitized chest radiographs of 18 patients with small peripheral lung cancers measuring less than 20 mm, which were displayed following 3 types of digital processing: 1) an original version; 2) unsharp mask processing with a type 1 filter (very low-frequency-enhancing, mid-frequency-suppressing, and high-frequency-enhancing filter); and 3) unsharp mask processing with a type 2 filter (very low- and high-frequency-enhancing filter). A total of 1,620 pooled observations were evaluated by receiver operating characteristic (ROC) analysis. RESULTS: The mean area under the ROC curves was 0.68 for the type 1 filter, 0.68 for the type 2 filter, and 0.65 for the unprocessed (original) image. There were no statistically significant differences among these 3 kinds of image processing (p>0.05). In all types of images, the small lung cancer with an alveolar lining tumor growth was less visible than a solid tumor growth (p<0.01); the sensitivity increased with tumor size when the 3 groups of cancers, those measuring less than 10 mm, 11-15 mm, and 16-20 mm, were compared (p<0.01). CONCLUSION: Unsharp mask-image processing of digital chest radiography will not improve the detection rate of small peripheral lung cancer, probably due to a substantial drawback: the limited conspicuity of cancer lesions in the surrounding lung and superposition of structures.  相似文献   
77.
BACKGROUND AND OBJECTIVES: This study compared the surface morphology as well as the biocompatibility of dental root cementum treated with Er:YAG laser irradiation alone and with the laser irradiation followed by chemical and/or mechanical conditioning. STUDY DESIGN/MATERIALS AND METHODS: Healthy cementum plates were randomly assigned to the following control and treatment groups: (1) untreated control (C), (2) Er:YAG laser irradiation (L), (3) laser plus tetracycline HCl (TC) placement (L+TP), (4) laser plus TC burnishing (L+TB), (5) laser plus EDTA gel placement (L+EP), (6) laser plus EDTA gel burnishing (L+EB), (7) laser plus saline solution burnishing (L+SB), and (8) laser plus minocycline-HCl paste placement (L+MP). Specimens were subjected to scanning electron microscopy (SEM), histological observation and attachment assay using periodontal ligament (PDL) fibroblasts. RESULTS: The laser irradiation produced a thin affected layer (5.7 microm thickness) with a superficial microstructure on the cementum surface. The characteristic microstructures of the lased surface were fragile and could be removed by chemical and/or mechanical conditioning treatments. The L+TB group exhibited marked exposure of collagen fibers after removal of the microstructures on the lased surface. The L+EP group presented a peculiar, smooth surface without exposure of collagen fibers and a uniform arrangement of spherical microparticles on the ultra-high magnification of SEM. In cell attachment assay, the L+TB group exhibited the greatest number of attached cells among all the groups, followed by the L+EP, L+SB and control group. The laser alone group exhibited the lowest number of cells. CONCLUSIONS: The characteristic microstructure of the root cementum surface after Er:YAG laser irradiation has a tendency to hinder the early attachment of PDL cells. However, chemical and/or mechanical root conditioning treatment may improve and increase the biocompatibility of the Er:YAG laser-treated root cementum by removing the microstructures of the surface and/or further exposing the collagen fibers.  相似文献   
78.
A 72-year-old man was admitted to another hospital because of general fatigue and dyspnea secondary to renal insufficiency. Abdominal computed tomography (CT) and magnetic resonance imaging showed left atrophic kidney, right hydronephrosis, and an intra-pelvic mass of soft-tissue density located anterior to the sacrum, involving the right ureter at the level between the 5th lumber vertebra and the sacrum. He was referred to our hospital after percutaneous nephrostomy was constructed into right kidney. CT-guided needle biopsy revealed the idiopathic retroperitoneal fibrosis, leading us to give him steroid therapy. Three weeks later, radiographic findings showed a remarkable reduction of the mass and the improvement of the right ureteral stricture.  相似文献   
79.
Background A reliable marker of chemoradiosensitivity that would enable appropriate and individualized treatment of thoracic squamous cell esophageal cancer has long been sought. We investigated whether regenerating gene (REG) Iα is such a marker. Methods We assessed expression of REG Iα in untreated endoscopic biopsy specimens and examined the correlation between REG Iα expression and the clinical responses to definitive chemoradiotherapy and prognosis. We also examined the relationship between REG Iα expression in the resected tumor and the prognosis of patients who received esophagectomy for thoracic squamous cell esophageal cancer. Results Among the 42 patients treated with definitive chemoradiotherapy, 8 of the 23 REG I-positive patients (35%) showed complete responses to chemoradiotherapy, while only one of the 19 REG I-negative patients did so. The survival rate among the REG I-positive patients was significantly better than among the REG I-negative patients. For the 76 patients treated surgically, there was no significant difference in the survival rates among the REG I-positive and REG I-negative patients. Conclusions REG Iα expression in squamous cell esophageal carcinoma may be a reliable marker of chemoradiosensitivity. We anticipate that it will enable us to provide more appropriate and individualized treatment to patients of advanced esophageal squamous cell carcinoma.  相似文献   
80.
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