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941.
A single center, prospective, epidemiologic study was conducted to estimate the incidence of deep venous thrombosis detected by venography in patients in Japan undergoing total hip arthroplasty or total knee arthroplasty without prophylactic anticoagulant therapy. Venograms of 164 patients who had total hip arthroplasty and 138 patients who had total knee arthroplasty were evaluated. The incidences of deep venous thrombosis were 22.6% in patients who had total hip arthroplasty and 48.6% in those who had total knee arthroplasty. The incidences of proximal deep venous thrombosis were 9.8% in patients who had total hip arthroplasty and 14.5% in those who had total knee arthroplasty. Statistical analysis revealed that the type of operation influenced the development of deep venous thrombosis. Patients who had total knee arthroplasty were 3.2 times more likely to have deep venous thrombosis develop than were patients who had total hip arthroplasty. Body mass index and age were identified as statistically significant risk factors.  相似文献   
942.
Alterations of the p16INK4a/p14ARF pathway in clear cell sarcoma   总被引:1,自引:0,他引:1  
Clear cell sarcoma (CCS) is a very rare soft tissue sarcoma with a poor prognosis. It has become apparent through immunohistochemical, ultrastructural, and microarray analyses that CCS is a soft tissue melanocytic neoplasm. Alterations in the p16INK4a/p14ARF gene are common in malignant melanoma, which is the prototypical melanocytic neoplasm. In the present study, we performed a clinicopathologic analysis and investigated p16 and cyclin D1 expression by immunohistochemistry in 14 cases. Furthermore, we investigated genetic changes of various tumor suppressor genes and an oncogene, including p16INK4a/p14ARF, p53, beta-catenin, and APC, in 11 cases. The 5-year overall survival rate in all the patients was 33.3%. A high mitotic rate was a significant adverse prognostic factor (P = 0.004). Decreased expression of p16 was observed in 4 (28.6%) of 14 cases. Overexpression of cyclin D1 was observed in 9 cases (64.3%). SSCP analysis followed by DNA direct sequencing revealed point mutations of the p16INK4a gene in 2 of 11 cases (18.2%). In addition, one case with the p14ARF mutation and 2 cases with the p53 mutation were observed. None of the cases harbored mutation of the beta-catenin or APC gene. Homozygous deletion of the p16INK4a/p14ARF gene was detected in one case. Methylation-specific PCR did not reveal hypermethylation of the p16INK4a/p14ARF promoter region in any of the cases. Three cases harbored genetic alterations of the p16INK4a/p14ARF gene (27.3%). All tumors with genetic alterations of the p16INK4a/p14ARF or p53 gene showed a high mitotic rate or tumor necrosis. These alterations were considered to be influential in the poor prognosis of CCS patients.  相似文献   
943.

Purpose

The clinical implications of mucinous components in rectal tumors, especially with regard to the efficacy of neoadjuvant chemoradiotherapy, remain unclear.

Methods

One hundred and thirty rectal cancer patients who received curative resection after neoadjuvant chemoradiotherapy were retrospectively reviewed. Patients were classified into 3 groups according to the proportion of extracellular mucin: low (<5 %), moderate (5–25 %), and high (>25 %).

Results

There were 82 (63.1 %), 26 (20.0 %), and 22 (16.9 %) patients in the low, moderate, and high mucin groups, respectively. Patients with a high mucinous tumor component were significantly more likely to have an advanced tumor stage (p = 0.010) and a shorter disease-free (p = 0.002) and distant recurrence-free survivals (p < 0.001), whereas the mucinous tumor component showed no correlation with local recurrence (p = 0.101). A high mucinous component was also an independent predictive factor for a shorter disease-free survival (p = 0.041, hazard ratio = 2.56) and distant recurrence-free survival (p = 0.001, hazard ratio = 5.74) according to a multivariate analysis.

Conclusions

Because the mucinous components showed little correlation with local recurrence, mucinous cancer should not be a determining factor for chemoradiotherapy. However, the frequent occurrence of metachronous distant metastasis among patients with a high mucin component makes this a possible indicator for more robust postoperative adjuvant treatment and close surveillance of recurrence.
  相似文献   
944.
945.
Periprocedural hemodynamic instability with carotid angioplasty and stenting   总被引:10,自引:0,他引:10  
Taha MM  Toma N  Sakaida H  Hori K  Maeda M  Asakura F  Fujimoto M  Matsushima S  Taki W 《Surgical neurology》2008,70(3):279-85; discussion 285-6
BACKGROUND: Carotid angioplasty and stenting is used for treatment of carotid stenosis. Stent deployment may induce HDI and thereby cause systemic or neurologic deficits. This study defines characteristics and predictors of HDI with CAS. METHODS: A total of 132 patients who had undergone CAS were evaluated for periprocedural and postprocedural HDI (hypertension, systolic blood pressure >160 mm Hg; hypotension, systolic blood pressure <90 mm Hg; or bradycardia, heart rate <60 beats per minute). RESULTS: Frequencies of HDI were 6.8% for hypertension, 32.6% for hypotension, and 15.9% for bradycardia. In addition, CAS of the right side (P < .01), carotid bulb lesions (P < .05), eccentric posterior carotid plaque (P < .0001), and general anesthesia (P < .05) were associated significantly with postprocedural HDI. Male sex (OR, 3.4; 95% CI, 1.8-67.2; P < .001), age of 80 years or older (OR, 0.4; 95%CI, 0.1-1.4; P = .011), and plaque ulceration (OR, 0.5; 95% CI, 0.1-9.5; P = .008) independently predicted postprocedural hypertension. Male sex (OR, 2.5; 95% CI, 1.3-24.9; P < .001), preprocedural major stroke (OR, 0.1; 95% CI, 0.01-0.8; P = .002), carotid bulb lesions (OR, 1.6; 95% CI, 1.1-25.9; P = .024), and contralateral carotid occlusion (OR, 0.6; 95% CI, 0.2-4.9; P = .040) all predicted postprocedural hypotension. Bradycardia was associated with diabetes mellitus (OR, 0.7; 95% CI, 0.3-2.4; P = .033), preprocedural TIA (OR, 1.7; 95% CI, 1.4-17.9; P = .020), and minor stroke (OR, 1.5; 95% CI, 1-10.9; P = .037). In 5 patients, HDI predisposed neurologic or systemic deterioration. CONCLUSIONS: Hemodynamic instability is common with CAS; hypotension and bradycardia are more frequent than hypertension. Some clinical, angiographic, and procedural variables can predict these HD changes.  相似文献   
946.
The aim of this report is to present the preliminary results of a Phase II study of high-dose (74 Gy RBE) proton beam therapy (PBT) with concurrent chemotherapy for unresectable locally advanced non-small-cell lung cancer (NSCLC). Patients were treated with PBT and chemotherapy with monthly cisplatin (on Day 1) and vinorelbine (on Days 1 and 8). The treatment doses were 74 Gy RBE for the primary site and 66 Gy RBE for the lymph nodes without elective lymph nodes. Adapted planning was made during the treatment. A total of 15 patients with Stage III NSCLC (IIIA: 4, IIIB: 11) were evaluated in this study. The median follow-up period was 21.7 months. None of the patients experienced Grade 4 or 5 non-hematologic toxicities. Acute pneumonitis was observed in three patients (Grade 1 in one, and Grade 3 in two), but Grade 3 pneumonitis was considered to be non-proton-related. Grade 3 acute esophagitis and dermatitis were observed in one and two patients, respectively. Severe ( ≥ Grade 3) leukocytopenia, neutropenia and thrombocytopenia were observed in 10 patients, seven patients and one patient, respectively. Late radiation Grades 2 and 3 pneumonitis was observed in one patient each. Six patients (40%) experienced local recurrence at the primary site and were treated with 74 Gy RBE. Disease progression was observed in 11 patients. The mean survival time was 26.7 months. We concluded that high-dose PBT with concurrent chemotherapy is safe to use in the treatment of unresectable Stage III NSCLC.  相似文献   
947.

Background

Nanoparticle albumin-bound (nab) paclitaxel is a promising new therapeutic agent for all histologic types of non–small-cell lung cancer (NSCLC). We recently performed a phase 2 study of weekly nab-paclitaxel in patients with previously treated advanced NSCLC, finding promising activity and acceptable toxicity for this regimen. We have now designed a randomized phase 3 intergroup study (J-AXEL, UMIN000017487) to examine the clinical benefit and safety of nab-paclitaxel compared to docetaxel in patients with previously treated advanced NSCLC.

Patients and Methods

Patients are randomized to receive either docetaxel (60 mg/m2 on day 1 every 3 weeks, control arm) or nab-paclitaxel (100 mg/m2 on days 1, 8, and 15 every 3 weeks, experimental arm), with each drug being administered until disease progression or unacceptable toxicity. The study will evaluate the noninferiority of nab-paclitaxel relative to docetaxel for the primary end point of overall survival.

Conclusion

If the primary objective is achieved, this study will provide evidence for a new alternative treatment option for patients with previously treated advanced NSCLC.  相似文献   
948.
BACKGROUND CONTEXT: Perforation of the esophagus after anterior cervical spine surgery is a rare, but well-recognized complication. The management of esophageal perforation is controversial, and either nonoperative or operative treatment can be selected. PURPOSE: Several reports have described the use of a sternocleidomastoid muscle flap for esophageal repair. In this case report, we describe a longus colli muscle flap as a substitute for a sternocleidomastoid flap in a patient with an esophageal perforation. STUDY DESIGN: Case report. PATIENT SAMPLE: A 20-year-old man sustained cervical spinal cord injury, on diving and hitting his head against the bottom of a pool. A C6 burst fracture was observed with posterior displacement of a bone fragment into the spinal canal. The patient exhibited complete paralysis below the C8 spinal segment level. METHODS: The patient underwent subtotal corpectomy of the sixth cervical vertebra with the iliac bone graft and augmented posterior spinal fixation (C5-7) with pedicle screws. After the primary operation, the patient showed signs of infection such as throat pain, a high fever, and osteolytic change of the grafted bone by cervical radiograph. A second operation was performed to replace the graft bone using fibula. On the day after the operation, food residue was confirmed in the suction drainage tube, suggesting esophagus perforation. A third operation was immediately performed to confirm and treat esophagus perforation, although apparent esophageal perforation could not be detected at the second operation. Because the erosion around the perforation of the esophageal posterior wall was extensive, a longus colli muscle flap transposition was accordingly performed into the interspace between the esophageal posterior wall and the grafted bone in addition to simple suturing of the perforation. RESULTS: Neither high fever nor pharyngeal pain has recurred at latest follow-up, 5 years after surgery. CONCLUSIONS: To the best of our knowledge, this is the first report concerning the use of a longus colli muscle flap for esophageal perforation after anterior cervical spine surgery.  相似文献   
949.
An arthroscopic and anatomical investigation was performed to define the abnormal conditions of the popliteal tendon area in a lateral meniscus. Arthroscopic findings for 100 patients and anatomical observations of 10 amputated knees were analyzed. Five of the 10 dissected menisci were also examined histologically. Menisco-tibial coronary ligaments were classified into two types, as follows: type I--a coronary ligament covering an entire popliteal tendon beneath the meniscus; type II--a popliteal tendon visible beneath the meniscus through defects of the coronary ligament. Twenty-one of 100 cases were classified as type I, and 79 were classified as type II. Three of the 10 anatomical dissections were type I, and the remaining 7 were type II. Menisci in which the type I coronary ligaments were thought to be torn and menisci with type II coronary ligaments showed a rather marked mobility, but no conclusion could be reached.  相似文献   
950.
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