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91.
YOSHIKAZU MURAWAKI YUJIRO IKUTA YUUKO NISHIMURA MASAHIKO KODA HIRONAKA KAWASAKI 《Journal of gastroenterology and hepatology》1996,11(5):443-450
In order to elucidate collagen metabolism in hepatocellular carcinoma (HCC) tissue, we compared levels of different potential markers of collagen metabolism and plasma transforming growth factor-β1 in patients with HCC and in patients with liver cirrhosis. Serum levels of prolyl hydroxylase and the tissue inhibitor of metalloproteinase-1 in patients with HCC were significantly higher than those in patients with liver cirrhosis and increased with the size of the HCC tumour, whereas the serum levels of procollagen type III propeptide and type IV collagen 7S domain were similar in the two groups. In HCC, the increased plasma transforming growth factor-β1 levels were closely correlated with serum levels of prolyl hydroxylase and the tissue inhibitor of metalloproteinase-1. These findings suggest that, in HCC tissue, the intracellular biosynthesis of collagen is enhanced, whereas the secretion of procollagen is disturbed and the degradation of collagen is suppressed by the excess production of the tissue inhibitor of metalloproteinase-1. The results also suggest that plasma transforming growth factor-β1 plays an important role in the altered metabolism of collagen in HCC. 相似文献
92.
实验冻伤大鼠神经纤维的超微结构改变 总被引:2,自引:1,他引:1
为探讨冷冻损伤发生、发展及转归的规律,采用健康Wistar大鼠,分为冻伤组(20只)和对照组(5只)。电镜下观察大鼠后肢冷冻至-20℃后即刻、4小时、24小时及72小时时周围神经的超微结构改变。冻后即刻,神经髓鞘即出现轻度变性;冻后1~24小时,有髓神经雪旺细胞及轴突严重变性,而无髓神经变性较轻;冻后72小时,神经溃变及修复并存,无髓神经较有髓神经易于修复。 相似文献
93.
94.
Gérard Brunel Edmond Benqué Frédéric Elharar Catherine Sansac Jean François Duffort Pierre Barthet Eric Baysse Neal Miller 《Clinical oral implants research》1998,9(5):303-312
The aim of the present study was to evaluate the combined application of different bioabsorbable materials for healing of residual peri‐implant defects after placement of non‐submerged implants into fresh extraction sockets. Second and third mandibular premolars were extracted from 10 Beagle dogs, the coronal part of the distal sockets were surgically enlarged and this was followed by immediate placement of specially designed hollow‐screw non‐submerged dental implants. For each animal, the coronal peri‐implant defects were further treated with one of the 4 following procedures: 1) no treatment, control site: 2) grafting with porous hydroxyapatite (HA); 3) collagen membrane tightly secured around the implant and over the defect and 4) grafting with HA covered with a collagen membrane. After 16 weeks of healing, specimens were removed from the mandibule and prepared for a histomorphometric evaluation. The bone-to-implant contact length (BIC) was measured and compared amongst the different treatment modalities. In the defect area, the irregular bone regeneration was similar between all the treatment procedures ( P >0.10). In the sites covered with a collagen membrane alone, the total BIC (47%) was greater than in control sites (28.7%. P <0.05) or sites grafted with HA (22.2%, P <0.02). Total BIC in sites treated with the HA‐membrane combination (43%) was only significantly different from sites treated with HA ( P <0.10). It is concluded that the use of bioabsorbable materials results in a limited increase of osseointegration when used in conjunction with immediate placement of non-submerged implants, although the principle of the one stage surgical approach can be maintained. 相似文献
95.
Seiitsu Ono Takashi Imai Shigeru Munakata Keiichi Takahashi Fumio Kanda Kazuki Hashimoto Takahiko Yamano Natsue Shimizu Koichi Nagao Mitsuo Yamauchi 《Journal of the neurological sciences》1998,160(2):565-147
During the last 10 years, we have demonstrated morphological and biochemical abnormalities of skin extracellular matrices in amyotrophic lateral sclerosis (ALS). However, currently little is known concerning collagen of the spinal cord in ALS. We measured the amount of collagen and characterized collagen at light and electron microscopic levels in posterior funiculus, posterior half of lateral funiculus and anterior horn of cervical enlargement of the spinal cord obtained from ten patients with ALS, 11 patients with other neurologic diseases (control group A), and ten patients without neurologic ones (control group B). In posterior half of lateral funiculus and anterior horn, (1) by light microscopy, there was no significant difference in vessel wall area between ALS patients and control groups A and B; (2) ultrastructurally, collagen bundles were more fragmented and widely separated, and the fibrils were randomly oriented in the perivascular space of capillaries in ALS patients, which were not observed in any areas of control groups or in posterior funiculus of ALS patients; and (3) the collagen contents in ALS were significantly lower (P<0.001 and P<0.001, respectively) than those in control groups A and B. Fragmented and widely separated collagen bundles in the interstitial tissue surrounding capillaries and markedly decreased amount of collagen in posterior half of lateral funiculus and in anterior horn of ALS could be related to the degeneration of the upper and lower motor neurons in the spinal cord in ALS, that is, selective neuronal vulnerability in ALS. 相似文献
96.
George Thabit III MD 《Operative Techniques in Sports Medicine》1998,6(3):157-160
The Holmium:YAG (Ho:YAG) laser is the arthroscopic laser of choice. The arthroscopic surgeon can ablate, coagulate, or shrink periarticular soft tissues by manipulating Ho:YAG laser power settings. The ability to ablate soft tissue in a hemostatic fashion greatly facilitates the treatment of labral tear, synovitis, subacromial arch decompression, and distal clavicle arthritis. The nonablative application of Ho:YAG laser energy has been used successfully to treat glenohumeral instability. The laser-assisted capsular shift (LACS) procedure, in conjunction with standard labral repair techniques, successfully treats unidirectional and multidirectional shoulder instability Neuromuscular rehabilitation is accelerated. Excellent clinical results may be achieved with appropriate surgical technique and postoperative rehabilitation. 相似文献
97.
Norio Ohkoshi Hldehlro Mizusawa Nobuko Shiraiwa Shin'Ichi Shoji Katsutoshi Harada Kazuo Yoshizawa 《Muscle & nerve》1995,18(11):1265-1271
Lmmunohistochemical analyses were made of the superoxide dismutases (Mn-SOD and CuiZn-SOD) in biopsied muscles from 7 patients with mitochondrial encephalomyopathies that included mitochondrial encephalomyopathy, lactic acidosis and strokelike episodes (MELAS), and chronic progressive external ophthalmoplegia (CPEO). Mn-SOD mainly was present in the subsarcolemmal region, but it also was found in a coarsely granular, reticular, or diffuse pattern of staining within the muscle fibers. These Mn-SOD-positive fibers corresponded almost completely to the ragged-red fibers. The immunoreaction for CuiZn-SOD was weakly positive in some of the muscle fibers positive for Mn-SOD. In CPEO, Mn-SOD-positive fibers predominantly showed decreased cytochrome c oxidase (COX) activity. In MELAS, Mn-SOD-positive fibers tended to be stained deeply for COX although a few were COX-negative. These findings suggest that Mn-SOD-positive fibers can be used to make a differential diagnosis between CPEO and MELAS and that in mitochondrial encephalomyopathies Mn-SOD in the raggedred fibers may protect against oxidative stress. © John Wiley & Sons, Inc. 相似文献
98.
膳食纤维与不同蛋白质联用对大鼠胆固醇代谢的影响 总被引:6,自引:0,他引:6
杨东仁 《中国慢性病预防与控制》1998,6(1):17-19,23
观察4种膳食纤维在两种蛋白来源下,对高脂血症大鼠生长、血脂、肝胆固醇、粪类固醇及胆汁成分的影响。结果表明:①四种膳食纤维均可降低大鼠血清TC水平,尤以豆胶效果显著。②豆胶显著升高HDL-C/LDL-C。膳食蛋白为大豆蛋白时,豆胶、沙棘皮可显著升高血清HDL-C、HDL-C/TC。③豆胶显著减少肝胆固醇累积,两种沙棘皮与大豆蛋白联用降脂强于与酪蛋白共用。④蛋白来源显著影响粪类固醇的排出,纤维类型可影响中性固醇排出并与蛋白质有交互作用。提示:蛋白质与膳食纤维之间的交互作用是探讨营养素与脂质代谢不可忽视的因素。 相似文献
99.
A significant increase of cutaneous laser Doppler flowmetry was found before blood flow decreases with increasing pressure during a 5 mmHg min−1 increase of pressure strain on the finger. Pre-treatment with a local anaesthetic or chronically applied capsaicin, resulted in the disappearance of the vasodilatory response. These results suggest an original vasodilatory axon reflex response to non-noxious pressure strain which is initiated by capsaicin-sensitive nerve terminals in the human skin. 相似文献
100.
The binding of type I collagen to its receptor initiates platelet aggregation, but the relationship of the receptor to other signal transduction components is not yet established. Correlation of platelet aggregation and anti-type I collagen receptor antibody immunoprecipitation of type I collagen treated [32PO4]-labeled platelets showed that there are two phosphoproteins (Mr 53 kDa and 21 kDa) that coprecipitated with the 65 kDa platelet type I collagen receptor. In the present investigation, we have identified one of the phosphoproteins. A soluble component the 100,000×g supernatant fraction of 53 kDa protein is recognized by polyclonal anti-PP1 antibody. The activity of the precipitated phosphatase is inhibited by okadaic acid and inhibitor 1, suggesting that it is protein phosphatase 1 (PP 1). Phosphorylation decreases PP 1 activity as was found with [32PO4]-phosphorylase b as the substrate. The immunocoprecipitation of the type-1 collagen receptor and PP 1 inot the result of cross reactivity of the anti-type I collagen receptor antibody with the PP I protein. These results indicate that the platelet type I collagen receptor, PP 1, and unidentified 21 kDa protein are in close association with the platelet type I collagen receptor upon the binding of type I collagen by the receptor. Copyright © 1996 Elsevier Science Ltd 相似文献