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We describe a new vascular access grafting technique featuring end-to-end anastomosis to a deep vein in the forearm, designed to create a functional arteriovenous fistula in the forearm of patients whose subcutaneous veins are not usable for this purpose because of occlusion or attenuation. This new technique offers a valuable option in this setting.  相似文献   
74.
 One hundred fifteen asymptomatic Japanese volunteers aged from 13 to 76 years were examined by magnetic resonance imaging (MRI) to evaluate age-related meniscal degeneration and to determine the prevalence of discoid menisci. Each meniscus was graded in the anterior and posterior portions according to intrameniscal MRI signals. Discoid meniscus was diagnosed if a bow-tie configuration was noted on three or more contiguous sagittal sections. Meniscal abnormalities on MRI became more prevalent with age in both men and women. The posterior horn of the medial meniscus showed a significantly higher prevalence of degeneration than other parts of the meniscus. Discoid menisci were noted in 15 subjects (13% prevalence), always representing the lateral meniscus. Subchondral changes were observed in 13 subjects more than 40 years old, mostly women, and were located in the medial compartment. These abnormalities were not correlated with severity of degeneration in the posterior portion of the medial meniscus. This study demonstrates considerable prevalence of meniscal abnormalities in asymptomatic Japanese subjects. Received: January 15, 2001 / Accepted: December 13, 2001  相似文献   
75.
Predicting pelvic lymph node metastasis in endometrial carcinoma   总被引:9,自引:0,他引:9  
BACKGROUND: To determine the possibility of individualizing the pelvic lymph node dissection in patients with endometrial cancer, the relationship between pelvic lymph node (PLN) metastasis and various prognostic factors was retrospectively investigated. METHODS: From 1979 to 1994, 175 patients with endometrial carcinoma were treated with either total or radical hysterectomy combined with a PLN dissection as initial therapy. The prognostic factors examined included clinical stage, patient age, histological grade, the microscopic degree of myometrial invasion (DMI), cervical invasion, adnexal metastasis, and macroscopic tumor diameter (TD). RESULTS: Of the 175 patients undergoing PLN dissection, 24 (14%) had PLN metastasis. An endometrial cancer with PLN metastasis had a significantly longer diameter than those without PLN metastasis. The frequency of PLN metastasis increased along with increases in tumor diameter. A logistic regression analysis revealed DMI and TD to be independently correlated with PLN metastasis. The formula based on the coefficients of TD and DMI obtained from the analysis also showed a good correlation, which allowed us to estimate the probability of patients having PLN metastasis. CONCLUSIONS: DMI and TD could accurately estimate the status of PLN in endometrial carcinoma patients.  相似文献   
76.
Local blood flow of the bowel wall was measured by hydrogen clearance method both in the muscular and submucosal layers in the mongrel dog, separately and concurrently. A platinum wire electrode with a bare tip of 0.5 mm in length and 0.2 mm in diameter was inserted into each layer. About 10 per cent hydrogen gas was inhalated directly through the side hole attached to the endotracheal tube for 1–2 minutes and the obtained clearance curves were plotted on the semi-logarithmic scale, which was almost monoexponential. The results obtained were as follows:
  1. Mean basal perfusion rate of the muscular layer of the intestine was 0.81–0.92 ml/min/gm, whereas that of the submucosal layer was 1.29–1.31 ml/min/gm, respectively. There was little difference of perfusion rates between the small and the large intestine. The results showed good correlationship with those reported by other authors.
  2. The effect of vasoactive substances such as vasoconstrictor and vasodilator on the local blood flow in the bowel wall was confirmed.
  3. This method is repeatedly applicable for measurement and also renders the information on the distribution of blood flow in the splanchnic area.
  相似文献   
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BACKGROUND AND AIMS: Many falls in the elderly are caused by tripping. After tripping, a certain level of lower-extremity functional fitness is necessary, in order to make protective responses and to avoid falling. The purpose of this study was to test whether our new exercise program (a square-stepping exercise: SSE) would improve lower-extremity functional fitness in the elderly. METHODS: Fifty-two individuals aged 60-80 years were divided into two groups (non-randomized control design); SSE (n=26) and controls (n=26). Lower-extremity functional fitness was defined as standing up from a lying position (agility), chair-stand in ten seconds (leg power), walking round two cones (locomotion speed), sit-and-reach (flexibility) and single-leg balance with eyes closed (balance). The SSE group participated in a six-month regimen of SSE once a week. SSE was performed on a thin mat of 250 cm by 100 cm, partitioned into 40 small squares (25 cm each side). SSE included not only forward steps but also backward, lateral and oblique steps, and step patterns were progressively made more complicated. Controls maintained their usual lifestyles. RESULTS: In the SSE group, significant improvements were observed in agility, leg power, locomotion speed, flexibility and balance. No significant changes were detected in any tests in the control group. CONCLUSIONS: The SSE program improved lower-extremity functional fitness, lack of which constitutes a risk factor for falls in the elderly. This program should be tested further to determine if it can effectively reduce the incidence of falls in the elderly.  相似文献   
79.
Serotonergic fibers have a general feature of extending diffusely throughout the brain and appear to innervate broad areas rather uniformly. The present study revealed marked regional difference in their immunoreactivities against serotonin transporter by using two antibodies that recognize either N- or C-terminal domain of the transporter. C-terminal-specific labeling was ubiquitous, whereas N-terminal-specific labeling was confined to hippocampal CA1 region, somatosensory cortex, and other areas, suggesting novel non-uniformity in the serotonergic system.  相似文献   
80.
BACKGROUND: The beneficial effects of beta-blocker therapy in patients with heart failure have been confirmed. However, the effects of beta-blockers on myocardial perfusion defects are unclear. The aim of this study was to evaluate the effect of beta-blockers on myocardial perfusion defects estimated by thallium-201 myocardial scintigraphy in patients with dilated cardiomyopathy (DCM) and to investigate the relationships between beta-blocker treatment and myocardial damage and cardiac function. METHODS:201Tl and echocardiography were performed in 37 patients before and after 6 months of beta-blocker therapy. Extent score (ES) by 201Tl was used to quantitate myocardial perfusion defects before and after treatment. RESULTS: ES was significantly decreased by beta-blocker therapy. According to the change in ES, DCM patients were classified into three groups, patients who improved, patients showing no change and patients who deteriorated. In the improvement and no-change groups, beta-blocker therapy induced a reduction in left ventricular dimensions and an associated increase in ejection fraction. However, in the deterioration group, left ventricular dimensions and ejection fraction were unchanged. There was a significant relationship between the change in left ventricular dimension at end-diastole and the change in ES. CONCLUSIONS: beta-Blocker therapy could attenuate myocardial perfusion defects in some patients with DCM. The improvement in left ventricular function associated with beta-blocker therapy may be related to the attenuation in myocardial perfusion defects.  相似文献   
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