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81.
Blood compatibility of surfaces modified by plasma polymerization   总被引:3,自引:0,他引:3  
Tubular blood-contacting polymeric materials were modified by plasma polymerization and evaluated in the baboon with respect to their capacity to induce both acute and chronic arterial thrombosis. Polymer surface composition was determined by electron spectroscopy for chemical analysis. Steady-state arterial thromboembolism was initiated by introducing tubular segments into chronic arteriovenous shunts. Rates of platelet destruction induced by the test materials were calculated from 111In-platelet survival measurements. Nine plasma polymers based on tetrafluoroethylene, hexafluoroethane, hexafluoroethane/H2, and methane, when deposited on silicone rubber, consumed platelets at rates ranging from 1.1-5.6 x 10(8) platelets/cm2-day. Since these values were near the lower detection limit for this test system, the plasma polymers were considered relatively nonthrombogenic. Acute thrombus formation was initiated by inserting expanded Teflon (Gore-Tex PTFE) vascular grafts into the shunt system. 111In-platelet deposition was measured by scintillation camera imaging over a 1-h exposure period. Standard PTFE grafts (10 cm x 4 mm i.d.) accumulated approximately 1 x 10(10) platelets over this interval. While modification of PTFE grafts with a plasma polymer based on hexafluoroethane/H2 did not alter graft surface morphology, platelet deposition was reduced by 87% as compared to the controls (p less than 0.001). We conclude that both the surface chemistry and texture of prosthetic materials influence thrombogenesis. The method of plasma polymerization may be useful for assessing the importance of these variables independently and, perhaps, for minimizing certain adverse blood-material interactions.  相似文献   
82.
The Chinese herbal medicine, "Kanbaku-taiso-to" (KT) which is a mixture of Glycyrrhizae Radix, Triticii Semen and Zizyphi Fructus, sometimes shows marked effects on insomnia, infantile convulsions and emotional irritability. To elucidate the mechanism of the sedative effect of KT, effects of KT on the transmembrane ionic currents and local anesthetic action were examined and the following results were obtained. KT showed an inhibition of sodium, calcium and potassium currents in snail neurons. KT showed an inhibitory effect on pentylenetetrazol-induced bursting activity. KT had local anesthetic action on frog nerve fibers. Together with our previous study, these results suggest that KT has an inhibitory effect on hyperexcitability of the neuronal membrane and this is the main cause of the sedative effect of KT.  相似文献   
83.
Microscopic cancer is extremely rare even among "occult breast cancers". We treated a 70 year old woman with complaints of serosanguineous nipple discharge which yielded cytologically Class V cancer cells. Microdochectomy was performed and intraductal carcinoma was verified histologically in serially cut sections. Following a simple mastectomy, she has been well with no evidence of recurrence or metastasis, at this time.  相似文献   
84.
BackgroundSagittal spino-pelvic malalignment in patients with chronic low back pain (CLBP) have been reported in the past, which may also affect cervical spine lesions. The purpose of this study is to investigate the cervical alignment in patients with CLBP.MethodOf the patients who visited an orthopedic specialist due to low back pain lasting more than three months, 121 cases (average 71.5-years-old, 46 male and 75 female) with whole standing spinal screening radiographs were reviewed (CLBP group). Cervical parameters included cervical lordosis (CL), C2–C7 sagittal vertical axis (C2-7 SVA), and the T1 slope minus CL (T1S-CL). Cervical spine deformity was defined as C2-7 SVA >4 cm, CL <0°, or T1S-CL ≧20°. We compared the cervical alignment of these patients with 121 age and gender matched volunteers (control group).ResultsThe prevalence of cervical spine deformity was significantly higher in the CLBP group than in the control group (20.7% vs. 10.7%, P = 0.034). The mean CL was smaller in the CLBP group than in the control group (16.1° vs. 21.4°, P = 0.002). The mean C2-7 SVA was 17.6 mm vs. 18.7 mm in the CLBP group and in the control group, respectively (P = 0.817). The mean T1S-CL was larger in the CLBP group than in the control group (9.1° vs. 3.5°, P < 0.001). Multivariate analysis showed that people with CLBP were more likely to have cervical deformities than people without CLBP (odds ratio 2.16, 95% confidence interval 1.006 to 4.637).ConclusionsThis study results suggest that people with CLBP present with worse cervical sagittal alignment and higher prevalence of cervical spine deformities than age and gender matched volunteers with no CLBP. This means CLBP impacts cervical spine lesions negatively.Level of evidenceⅣ  相似文献   
85.
Hereditary apolipoprotein A-1 (ApoA-1) amyloidosis is a rare disease characterized by progressive deposition of amyloid fibrils in the kidney, heart, and liver. We observed a 45-year-old male patient with liver failure. Liver dysfunction was detected at 30 years of age during an annual health check-up. At 35 years of age, renal dysfunction was also found. At 40 years of age, the pathologic findings of the liver revealed amyloid deposition. A testis biopsy specimen taken at 42 years of age to identify the cause of male infertility showed amyloid accumulation. At 43 years of age, the amyloid results and genetic profile led to a definitive diagnosis of hereditary ApoA-1 amyloidosis caused by Glu34Lys mutation. A family history was absent. Liver failure showed Budd-Chiari–like formation, including enlargement of the caudate lobe and liver congestion. Although the patient showed end-stage liver cirrhosis and renal failure, only liver transplant was performed considering the burden for a living donor. The enlarged liver (4.9 kg) showed amyloid deposition in parenchyma and the space of Disse. Amyloid also accumulated in the giant spleen. The APOA1 mutation Glu34Lys is extremely rare, and in this case hepatic failure was successfully treated by liver transplant to both replace organ function and reduce production of the amyloidogenic ApoA-1–variant protein. Careful observation for reaccumulation of amyloidosis in the organ is required.  相似文献   
86.
87.
Transgenic expression in medaka of the Xiphophorus oncogene xmrk, under a pigment cell specific mitf promoter, induces hyperpigmentation and pigment cell tumors. In this study, we crossed the Hd-rR and HNI inbred strains because complete genome information is readily available for molecular and genetic analysis. We prepared an Hd-rR (p53+/−, p53−/−) and Hd-rR HNI hybrid (p53+/−) fish-based xmrk model system to study the progression of pigment cells from hyperpigmentation to malignant tumors on different genetic backgrounds. In all strains examined, most of the initial hyperpigmentation occurred in the posterior region. On the Hd-rR background, mitf:xmrk-induced tumorigenesis was less frequent in p53+/− fish than in p53−/− fish. The incidence of hyperpigmentation was more frequent in Hd-rR/HNI hybrids than in Hd-rR homozygotes; however, the frequency of malignant tumors was low, which suggested the presence of a tumor suppressor in HNI genetic background fish. The effects on tumorigenesis in xmrk-transgenic immature medaka of a single 1.3 Gy irradiation was assessed by quantifying tumor progression over 4 consecutive months. The results demonstrate that irradiation has a different level of suppressive effect on the frequency of hyperpigmentation in purebred Hd-rR compared with hybrids.  相似文献   
88.
Pharyngeal cancer patients treated with intensity-modulated proton therapy (IMPT) using a model-based approach were retrospectively reviewed, and acute toxicities were analyzed. From June 2016 to March 2019, 15 pharyngeal (7 naso-, 5 oro- and 3 hypo-pharyngeal) cancer patients received IMPT with robust optimization. Simulation plans for IMPT and intensity-modulated X-ray therapy (IMXT) were generated before treatment. We also reviewed 127 pharyngeal cancer patients with IMXT in the same treatment period. In the simulation planning comparison, all of the normal-tissue complication probability values for dysphagia, dysgeusia, tube-feeding dependence and xerostomia were lower for IMPT than for IMXT in the 15 patients. After completing IMPT, 13 patients completed the evaluation, and 12 of these patients had a complete response. The proportions of patients who experienced grade 2 or worse acute toxicities in the IMPT and IMXT cohorts were 21.4 and 56.5% for dysphagia (P < 0.05), 46.7 and 76.3% for dysgeusia (P < 0.05), 73.3 and 62.8% for xerostomia (P = 0.43), 73.3 and 90.6% for mucositis (P = 0.08) and 66.7 and 76.4% for dermatitis (P = 0.42), respectively. Multivariate analysis revealed that IMPT was independently associated with a lower rate of grade 2 or worse dysphagia and dysgeusia. After propensity score matching, 12 pairs of IMPT and IMXT patients were selected. Dysphagia was also statistically lower in IMPT than in IMXT (P < 0.05). IMPT using a model-based approach may have clinical benefits for acute dysphagia.  相似文献   
89.
90.
In this study, we examined complement activation by mycoloyl glycolipids (MGL) such as trehalose-6,6'-dimycolate (TDM), often termed cord factor, and trehalose-6-monomycolate from Mycobacterium tuberculosis and Rhodococcus ruber, and also examined the effect of complement binding to MGL on phagocytosis by human monocytes. TDM and TMM, but not glucose mycolate, mannose mycolate or fructose mycolate which differ from TMM only in carbohydrate moiety, exhibited complement activation. TDM and TMM of M.tuberculosis exhibited stronger complement activation than those of R.ruber, the mycolic acids of which are much shorter than those of M.tuberculosis. Neither mycolic acids nor trehalose, which are products of TDM and TMM by hydrolytic cleavage, exhibited no complement activation. TDM activated complement through the alternative pathway, since supplementation with C4-deficient serum completely restored classical pathway-mediated hemolytic activity of complement which had been previously consumed by TDM. Next, we examined the effects of TDM and TMM on phagocytosis by human monocytes. Coating of heat-killed Staphylococcus aureus cells with TDM or TMM did not enhance their phagocytosis by monocytes, while, in the presence of complement, phagocytosis of these cells increased significantly. These findings suggest that TDM and TMM act as virulence factors that enhance the entry of mycobacteria into phagocytes via binding of C3 through activation of the alternative complement pathway.  相似文献   
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