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41.
The objective of this study is to develop a sensitive temperature-responsive material that would function near body temperature. To achieve this purpose, we compounded 2-branched and 4-branched poly(epsilon-caprolactone) macromonomers to modulate the transition temperatures of the resulting cross-linked materials. The temperature-responsive properties were studied using differential scanning calorimetry and X-ray diffraction measurements. As a result, the mixing ratios of each macromonomer or the total macromonomer concentrations were very dominant in modulating the transition temperatures. The materials could successfully control the permeation of the model drug, prednisolone, near body temperature.  相似文献   
42.
Aim:  This study aims to establish a pressure ulcers model that visualizes the microcirculation, and to examine the participation of ischemia‐reperfusion injury in the pathophysiology of pressure ulcers.
Methods:  An original system composed of a new skinfold chamber and compression device allowed loading quantitative vertical stress to the skin. An intravital microscopic technique enabled direct visualization of the microcirculation in the physiological condition and in response to pressure application. To estimate the effect of ischemia‐reperfusion injury, animals were divided into two groups: the compression‐release group in which the animals received four cycles of compression‐release which consisted of 2 hours of compression followed by 1 hour of pressure release; and the compression alone group in which the animals underwent continuous compression for 8 hours. Functional capillary density was quantified before the compression procedure and on day1 (35 hours) after the first evaluation.
Results and Conclusions:  The cyclic compression‐release procedure significantly decreased functional capillary density as compared to continuous compression, indicating that in our experimental setting repetition of ischemia‐reperfusion cycle more severely damaged the microcirculation than single prolonged ischemic insult. The finding supports the significant contribution of ischemia‐reperfusion injury to the pathophysiology of pressure ulcers at the level of dynamic in vivo microcirculation.  相似文献   
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Subdural hygroma is a frequent delayed complication of head trauma. Most hygromas are clinically 'silent' and a few cases have shown slow deterioration in the chronic stage. We report a case of subdural hygroma showing unique radiological findings and rapid deterioration. A 74-years-old female presented with a mild headache and consciousness disturbance after head injury. Computed tomography showed a midline shift as a result of two components piling up in the subdural space; the outer components showed low density, the inner components high density. Magnetic resonance imaging demonstrated that these two subdural components were subdural hygroma and subarachnoid hematoma. Simple burr hole irrigation, rather than large craniotomy, was thought to be more appropriate treatment to reduce the mass effect. Simple burr hole irrigation was performed to remove the subdural hygroma and the patient showed an excellent recovery. Careful examination of the radiological findings prevented an unnecessary procedure in this case. A possible mechanism of this phenomenon is discussed.  相似文献   
45.
Giant aneurysms are the most serious issue of patients with Kawasaki disease (KD). To clarify risk factors for these giant aneurysms, we conducted a matched case-control study. Among the patients reported in nationwide surveys, 117 patients with giant aneurysms had an unequivocal new diagnosis and presented at the treatment center within 9 d of illness. We obtained clinical information on admission of about 69 patients (case) from the treatment centers. One control was selected for each case, an age- and sex-matched patient without coronary involvement, reported from the same treatment center at about the same time as the case, and we obtained the same clinical information about controls. Fourteen variables were analysed with a conditional logistic regression model: body temperature, hematocrit, hemoglobin, numbers of leukocyte and platelets, concentrations of serum albumin, globulin, total cholesterol, sodium, potassium and chloride, erythrocyte sedimentation rate, C-reactive protein and alanine aminotransferase activity. After adjustment for age, duration of illness before admission and use of intravenous gamma globulin therapy, C-reactive protein [odds ratio (OR) = 1.142, 95% confidence interval (CI) 1.054-1.237], alanine aminotransferase activity (OR = 1.008, 95% CI 1.002-1.014), serum sodium concentration (OR = 0.877, 95% CI 0.770-0.999) and serum potassium concentration (OR = 0.319, 95% CI 0.124-0.822) were significantly related to the risk for giant aneurysms. Further analyses with these four explanatory variables revealed that C-reactive protein (OR = 1.159, 95% CI 1.022-1.315) and serum potassium concentration (OR = 0.222, 95% CI 0.052-0.948) met the significant level. Thus, the values for serum C-reactive protein and potassium are independent risk factors for the development of the giant aneurysms of Kawasaki disease.  相似文献   
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Background. A membrane oxygenator consisting of a microporous polypropylene hollow fiber with a 0.2-μm ultrathin silicone layer (cyclosiloxane) was developed. Animal experimental and preliminary clinical studies evaluated its reliability in bypass procedures.

Methods. Five 24-hour venoarterial bypass periods were conducted on dogs using the oxygenator (group A). In 5 controls, bypass periods were conducted using the same oxygenator without silicone coating (group B). As a preliminary clinical study, 14 patients underwent cardiopulmonary bypass with the silicone-coated oxygenator.

Results. Eight to 16 hours (mean, 12.2 hours) after initiation of bypass, plasma leakage occurred in all group B animals, but none in group A. The O2 and CO2 transfer rates after 24 hours in group A were significantly higher than at termination of bypass in group B (p < 0.005 and p < 0.03, respectively). Scanning electron microscopy of silicone-coated fibers after 24 hours of bypass revealed no damage to the silicone coating of the polypropylene hollow fibers. In the clinical study, the oxygenator showed good gas transfer, acceptable pressure loss, low hemolysis, and good durability.

Conclusions. This oxygenator is more durable and offers greater gas transfer capabilities than the previous generation of oxygenators.  相似文献   

49.
This study was undertaken in an attempt to find factors which affected the recent declining birth rate in Tokyo. Vital statistics of the female population, age 20-39, for the period of 1970 through 1985 for Tokyo were compared to national averages. Indices examined were birth rate, percentage of married women, birth rate for married women, and birth rate for married women by live birth order. Results thus obtained were as follows: 1. Birth rates for females aged 20-24 and 25-29 were largely dependent on percentages of married women rather than birth rates for married women both in Tokyo and in the nation as a whole, while the birth rates for females aged 30-34 and 35-39 were more dependent on birth rates for married women. 2. Percentages of married women aged 20-24 and 25-29 decreased during the observation period both in Tokyo and in the nation as a whole. 3. Birth rates for married women aged 30-34 and 35-39 dropped in the first 5 or 10 years of observation in both groups as a result of the reduction in high order live births. Thereafter, the decline changed to an upturn trend. 4. Yearly changes of birth rate, percentage of married women, birth rate for married women, birth rate for married women by live birth order, and birth rate of first child for married women appeared to have the same timing both in Tokyo and in Japan as a whole in each age category.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
50.
p = 0.0007) and tumor necrosis (TN) (HMC: p = 0.0050). Univariate analysis showed that AMC or HMC was a statistically significant predictor of overall survival in all patients ( p = 0.0086 and p = 0.0307, respectively). Multivariate analysis showed that AMC was an independent predictor of node status when we fitted a model with node status, BVI, and either AMC or HMC; but HMC was not independent. However, when we fitted a model including all 11 of the other indicators and AMC or HMC, the node status, HG, and LI were independent predictors, but AMC and HMC were not. Although AMC was a better method than HMC for evaluating angiogenesis, we cannot confirm angiogenesis as a significant independent prognostic factor associated with long-term survival in Japanese breast cancer patients.  相似文献   
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