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71.

Background

Lymphaticovenular anastomosis (LVA) is generally an effective procedure for breast cancer treatment-related upper extremity lymphedema (UEL). Clinical improvement is, however, limited by the degree of sclerosis of the lymphatic vessels. We have developed a method by which we use dynamic ultrasonography to depict vessels through which lymph can be propelled into the LVA under the power of the patient's natural hand movements.

Methods

We assessed the dynamic-LVA method by comparing clinical details of 15 cases of breast cancer treatment-related lymphedema treated by dynamic LVA and 15 corresponding cases treated by conventional LVA.

Results

Placement of incisions at a total of 90 forearm sites (three per patient) yielded 90 LVAs (32 in “linear ICG lymphography pattern incisions” and 58 in “stardust pattern incisions”). Sclerotic lymphatic vessels were encountered at greater frequency in “linear pattern incisions” in the dynamic LVA group than in the conventional LVA group (7.1% vs. 38.9%, P?=?0.030). Postoperative volume reduction was significantly greater in the dynamic LVA group than in the conventional LVA group; the UEL index at 1 month was 8.12?±?3.08?vs. 3.74?±?5.82, respectively (P?=?0.018), and at 1 year was 10.23?±?6.16?vs. 2.03?±?9.36, respectively (P?=?0.014).

Conclusions

Dynamic LVA is clinically beneficial because the imaging guides decisions over the locations where the incisions should be placed so that a patient's natural hand motions can be used to propel lymph into the anastomosis despite the presence of sclerosis and because even early improvements are obtained.  相似文献   
72.
Background:   Vertebroplasty is a procedure in which bone cement is injected percutaneously into the vertebral body.
Methods:   We used this technique with 15 patients who had pseudarthrosis or delayed union of osteoporotic spinal fractures with vacuum clefts, and in whom conservative treatment did not relieve persistent pain. The procedure was performed in a short time with little blood loss, and no generic complications, leakage of bone cement to blood vessels or the spinal canal, or neural compression.
Results:   At 1 week after the operation, pain was eliminated in seven patients, alleviated in seven patients, unchanged in one patient, and worsened in none. The rate of alleviation or elimination of pain after 1 week and 6 months was 93% and 85%, respectively. Recurrence of the pain was seen in four cases, but this was caused by new spinal fractures in separate locations, confirmed with magnetic resonance imaging, in three patients, and by multiple myeloma in one patient.
Conclusion:   Thus, vertebroplasty, which alleviates pain rapidly and with low invasiveness, is a new and promising therapy for osteoporotic spinal fractures in which conservative treatment has failed. It seems to provide a large benefit to elderly patients if performed with prudent care with regard to complications at the time of bone cement injection, and in conjunction with treatment for osteoporosis.  相似文献   
73.
Introduction A wrong diagnosis of latent vertebral fracture is often made when it is based on plain X-ray imaging. Magnetic resonance imaging (MRI) has a high degree of accuracy for the definite diagnosis. This study was designed to identify ways to support improvements in the diagnostic accuracy of plain X-ray (X-P).Methods We studied X-P and MRI images of 120 women and men (age range: 50–96 years). Five orthopedists and two radiologists interpreted front and lateral thoracolumbar X-Ps and MRI images. The correct diagnosis rate for the presence and location of incident vertebral fractures and the correct diagnosis rate according to morphological classifications were analyzed.Results A correct diagnosis of incident fractures was made in 51.5% of cases overall. Diagnoses of non-incident fracture based on X-P in those cases with incident fracture based on MRI (false positive) occurred in 24.8% of the patients, while diagnoses of incident fracture based on X-P in those cases without incident fracture based on MRI (false negative) occurred in 6.5% of the patients. The application of morphological classifications (the primary osteoporosis diagnostic criteria and Yoshida’s classification) resulted in the correct diagnosis rate being significantly higher in the group without prevalent fracture even when there were morphological changes (wedge, indented, protruding type) in the anterior bone cortex. Odds ratios were investigated for factors that would affect the correct diagnosis rate, including age, body weight, lumbar vertebrae bone mineral density, and examiner ability. In an overall investigation, age (OR=0.660), body weight (OR=2.082), and examiner ability (p=0.0205) affected the correct diagnosis rate.Conclusion The correct diagnosis rate for incident vertebral fractures with X-Ps was low (24.8%) and in cases with prevalent fractures, the rate was even lower (16.8%), but the number of prevalent fractures and BMD did not exert an effect. One key improving the correct diagnosis rate may be to pay attention to morphological changes in the anterior bone cortex.  相似文献   
74.
75.
Helical Computed Tomography Scanning of the Thorax and Abdomen   总被引:1,自引:2,他引:1  
We applied helical CT to examinations of the abdomen and thorax.Scanning was performed continuously while the couchtop of theCT scanner was shifted at a constant speed. The entire lungfield could be scanned during a single holding of the breathwhen the couchtop speed was 20 mm/s. Tumors as small as 3 mmwere detected. The diagnostic detectability and accuracy ofhelical CT were far superior to those of conventional chestradiography. During abdominal examination, the target organcould be scanned at any specified phase (preferably arterial)during the injection of contrast medium. We detected very smallhepatic tumors which could not be detected by conventional CT.Helical CT produced continuous data, which was reconstructedto display three-dimensional images. Helical CT could be usedin mass screening for the detection of early lung cancer andin computer-aided diagnosis.  相似文献   
76.

Probucol is an antihyperlipidemic drug with potent antioxidant properties. Oxidative stress plays an important role in the pathogenesis of diabetic retinopathy. In this study, we aimed to investigate the protective effects of probucol against diabetes-induced retinal vascular dysfunction in a rat model of diabetes. Diabetes was induced by a combination of streptozotocin treatment and D-glucose feeding, and retinal vasodilator responses were assessed by measuring the diameter of retinal arterioles. The vasodilator effect of salbutamol, a β2-adrenoceptor agonist, on retinal arterioles was significantly diminished 2 weeks after the induction of diabetes. In non-diabetic rats, vasodilator responses to salbutamol were significantly reduced after an intravitreal injection of iberiotoxin, a blocker of large-conductance KCa (BKCa) channels. However, this effect was not observed in diabetic rats. Probucol had no significant effect on salbutamol-induced changes in diameter of retinal arterioles in non-diabetic rats, whereas it could prevent the attenuation of retinal vasodilator response to salbutamol in diabetic rats. These results suggest that the reduced function of BKCa channels is involved in the attenuation of β2-adrenoceptor-mediated retinal vasodilation in diabetic rats. Probucol preserves the BKCa channel function in retinal arterioles under diabetic conditions; therefore, it may show beneficial effects on diabetic retinopathy by preventing or slowing the impairment of the retinal circulation in patients with diabetes mellitus.

  相似文献   
77.

Introduction

At present, cribriform arrangements are regarded as a pattern of acinar adenocarcinoma. However, recent studies have indicated that clinical outcomes for lung adenocarcinoma patients with cribriform subtype are unfavorable. To validate the prognostic significance of the cribriform pattern, we analyzed a series of 735 Japanese patients with resected lung adenocarcinoma, which was restaged according to the eighth edition of the TNM staging system.

Methods

Tumors were classified in accordance with the 2015 WHO classification of lung carcinomas. The cribriform pattern was defined by invasive back-to-back fused tumor glands with poorly formed glandular spaces or invasive tumor nests of tumors cells that produce glandular lumina. Recurrence-free probability (RFP) and overall survival (OS) was analyzed using the log-rank test and the Cox proportional hazards model.

Results

After the addition of the cribriform pattern, 54 of 90 acinar-predominant tumors were reclassified as cribriform subtype. Five-year RFP for patients with the cribriform subtype (51%) was lower than it was for patients with acinar and papillary subtype (81% and 80%, respectively) but was comparable to that for patients with solid subtype (48%). Five-year OS for patients with the cribriform subtype (49%) was lower than it was for patients with acinar and papillary subtype (90% and 81%, respectively). On multivariate analysis adjusted for the eighth edition of the TNM staging system, the cribriform subtype was an independent prognostic factor of a worse RFP and OS.

Conclusions

We have validated that the cribriform subtype is an independent factor of poor prognosis in patients with resected lung adenocarcinoma.  相似文献   
78.
79.
OBJECTIVE AND METHODS: We examined the prognostic significance of electrocardiographic predictors (number of leads with ST depression, maximal ST depression, QT dispersion), C-reactive protein, fibrinogen, myosin light chain 1 and creatine kinase MB fraction in 62 patients with unstable angina showing ST depression during an anginal attack. RESULTS: During the 90-day follow-up period, 15 patients (24%) exhibited new cardiac events (death, myocardial infarction or urgent revascularization). Using multivariate analysis, the number of leads with ST depression [relative risk 6.305 (95% confidence intervals 1.831-21.71), p<0.01] during an anginal attack was found to be an independent risk factor to predict cardiac events. Other predictors did not have prognostic significance. CONCLUSION: The number of leads with ST depression during an anginal attack is an independent risk predictor for new cardiac events in high risk patients with unstable angina.  相似文献   
80.
PURPOSE: The susceptibility of male p53 nullizygote (-/-), heterozygote (+/-), and wild-type (+/+) mice to 1,2-dimethylhydrazine (DMH) induction of colon carcinogenesis was investigated. METHODS: In a preliminary short-term experiment, male mice of three genotypes were given s.c. of 20 mg/kg DMH once weekly for 5 weeks. In a medium-term experiment, mice were given weekly s.c. of DMH for 15 weeks. In a long-term experiment, male p53 (+/-) and (+/+) mice were given weekly injections of DMH for 15 weeks, and killed at week 30. RESULTS: In the medium-term experiment, carcinomas were observed in 70% of p53 (-/-) mice, although there were no carcinomas in p53 (+/+) and (+/-) mice. In the long-term experiment, there was no significant difference in incidences of adenomas and carcinomas between p53 (+/+) and (+/-) mice. PCR-single strand conformation polymorphism analysis of exons 5-8 of p53 gene revealed four mutations in one focal atypia, one adenoma, and two carcinomas, out of 56 colonic proliferative lesions in the medium- and long-term experiments. CONCLUSIONS: These results suggest that p53 might not be a direct target of DMH but complete loss of p53 might elevate susceptibility to DMH-induced colorectal carcinogenesis.  相似文献   
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