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91.
Lutz Claes Nikola Maurer-Klein Thomas Henke Heinz Gerngross Mark Melnyk Peter Augat 《Journal of orthopaedic research》2006,24(6):1178-1185
The aim of this study was to investigate the effect of a moderate soft tissue trauma to the course of fracture healing in a standardized animal model. Thirty-eight Wistar rats were randomly divided into a fracture group (F, n = 19) and a group with a fracture and a soft tissue trauma (F + STT, n = 19). The fracture and the soft tissue trauma were created using an impact device with a standardized energy. All fractures were stabilized by two Kirschner wires. Three rats were measured for blood flow and sacrificed at days 1, 3, 7, and 14, and seven rats at day 28, from both groups. A three-point bending test was performed on the healed tibia after 28 days. During the first 24 h there was a reduction in blood flow, which was more pronounced in the F + STT group than in the F group. From histological sections, the shape of the callus formation, as well as the tissue distribution of newly formed bone, fibrous cartilage and fibrous connective tissue were determined. Distinctly more periosteal new bone formed and a larger callus formed at days 3 and 7 in group F compared to group F + STT. However, by days 14 and 28, the ossification and overall callus size no longer showed differences between the two groups. A fast recovery of blood flow and callus formation took place in the F + STT group, which led to similar histological and biomechanical results in fracture healing observed after 28 days between the two groups. 相似文献
92.
Inflammatory biomarkers in blood of patients with acute brain ischemia 总被引:11,自引:0,他引:11
S. Sotgiu B. Zanda B. Marchetti M. L. Fois G. Arru G. M. Pes F. S. Salaris A. Arru A. Pirisi G. Rosati 《European journal of neurology》2006,13(5):505-513
Although many failed surrogate markers are provided in the literature, inflammation may contribute to the outcome of ischemic stroke. In 50 consecutive patients with acute ischemic stroke, in the absence of symptoms and signs of concomitant infection, we evaluated a panel of biomarkers reported to be variably associated with brain ischemia, and correlate their serum level with the brain lesion volume and clinical outcome. Infarct size was calculated on computed tomography (CT) scans by means of the Cavalieri's method. Neurological impairment was scored by using the Glasgow Coma Scale, Glasgow Outcome Scale and National Institutes of Health (NIH) scales at stroke onset and 3-month follow-up. Some markers showed a direct significant correlation with both initial and final NIH scale and with infarct size, particularly tumor necrosis factor alpha (TNF-alpha) (P=0.002), intercellular adhesion molecule-1 (P<0.01) and matrix metalloproteinase-2/9 (P=0.001). In contrast to previous reports, interleukin-6 (IL-6) serum level showed a significant inverse correlation with both final neurological impairment and infarct size (P<0.001). This novel finding allows us suggesting that IL-6, in the context of a complex pro-inflammatory network occurring during stroke, is associated with neuroprotection rather than neurotoxicity in patients with ischemic brain injury. 相似文献
93.
Alfred Heller Lisa Won Barbara Heller Philip C. Hoffmann 《Clinical and experimental pharmacology & physiology》1995,22(5):375-378
1. The rotation-mediated three-dimensional reaggregate culture system is uniquely suited for studies on developmental neurotoxicity. In this system, it is possible to reconstruct central neuronal pathways and follow their development. 2. Exposure to drugs of abuse including methamphetamine and methylenedioxyamphetamine or the appetite suppressant, fenfluramine, reduces monoamines in the cultures in a dose-dependent manner and interrupts normal monoaminergic development. 3. While the monoaminergic neurones may attain normal rates of development following drug removal, the affected neurones are not capable of overcoming the drug-induced insults and a deficiency in monoamines persists throughout development. 4. In addition, the production of immortalized monoclonal hybrid cells obtained by fusion of fetal mesencephalic neurones with a neuroblastoma has yielded cell lines expressing a dopaminergic phenotype. 5. Such cells have been useful in establishing the relationship of neurotoxicity to cell lineage and can serve as models for the study of the cellular and molecular mechanisms of neurotoxicity. 相似文献
94.
Koibuchi Yukio; Iino Yuichi; Joshita Takashi; Yokoe Takao; Shinkai Hiroko; Kawashima Kenji; Kobayash Junya; Tanaka Sunao; Oyama Tetsunari; Hikino Toshiaki; Morishita Yasuo 《Japanese journal of clinical oncology》1995,25(6):273-277
A 66-year-old woman time of 10 days. One month after radicalmastectomy, there was local recurrence, followed by multiplepulmonary metastases, and the patient died of respiratory failure5 months after surgery. The gray-white-colored tumor measured13x12x;10 cm, and its border was well defined. The tumor wascomposed of diffusely growing round or polygonal cells withvesicular nuclei, prominent nucleoli, and ample cytoplasm containingeosinophilic inclusions. Lymph node involvement was widespread.Both vimentin and keratin were clearly demonstrated by immunohistochemicalstaining. Ultrastructural studies revealed that the MRT cellscontained cytoplasmic whorls of intermediate filaments. 相似文献
95.
Mayumi Ujihara Sumiko Hamanaka Sachie Matsuda Fumitaka Numa Hiroshi Kato 《The Journal of dermatology》1994,21(1):56-58
A 76-year-old female was admitted with many bullae and erythema on her trunk and extremities. A biopsy specimen showed significant intercellular edema in the lower epidermis and eosinophilic infiltration into the dermis and the epidermis. Immunofluorescent staining revealed the deposition of IgG in the intercellular area of her prickle cells. From these histologic findings and the typical clinical features, we diagnosed her as having pemphigus vulgaris. Examination of her blood revealed that she also suffered from autoimmune hemolytic anemia. Despite intensive treatment with prednisolone, she finally died. This case is of interest because of its rarity and the TNFα detected significantly in the blister fluid of this patient. 相似文献
96.
The present study investigated the phototoxic effect of bergamot oil and its photosensitive component, bergapten, on sunburn cell (SBC) production in guinea pig skin. The back skin was pretreated with bergamot oil or bergapten and exposed to monochromatic light under various conditions. After irradiation, skin specimens were excised, and histological sections were prepared. The number of sunburn cells in the interfollicular epidermis was counted. The SBC formation by bergamot oil or bergapten plus UVB radiation was the same as that without pretreatment with any photosensitizer. In contrast, a significant number of SBCs were induced by bergamot oil or bergapten plus UVA radiation, but no SBCs were found after the treatment with UVA alone. The result indicates that bergamot oil or bergapten was photosensitized by UVA irradiation. The SBCs were linearly increased in a UV-dose dependent manner. On the basis of the regression lines, an action spectrum and spectral peak for the photosensitizers plus UVA were obtained. The action spectrum for bergamot oil- and bergapten-induced SBC formation was in the ranges of 325–365 nm and 325–350 nm, and their spectral peaks were at 335–345 nm and 335–350 nm, respectively. The data are in good accordance with those estimated from skin erythema reactions. Therefore, counting SBCs is a very useful parameter for quantitative evaluation of phototoxicity. 相似文献
97.
Masayoshi Johno Munashi Oishi Masahiro Kohmaru Kohji Yoshimura Tomomichi Ono 《The Journal of dermatology》1994,21(3):197-204
A boy with skin eruptions resembling varicella and specific for Langerhans cell histiocytosis (LCH) is reported. At his initial visit when he was four months old, vesiculopustular lesions were present over the entire body; these had first appeared on the third day post partus. Histopathological, immunohistochemical, and electron microscopical examination confirmed the Langerhans cell phenotype and Birbeck granules in the responsible cells. He also had hydronephrosis, recurrent fever, and cutaneous bacterial infections. His parents refused further medical treatment and he died of diarrhea with cachexia about two years later. LCH may present diagnostic difficulties by manifesting as a skin eruption which resembles varicella. 相似文献
98.
99.
Summary In this study the technique of labelling the cell membrane with DPH fluorescence polarization was used to observe the membrane
fluidity of B lymphocytic cell lines and tonsillar cells from healthy persons; the modulation effect on membrane-fluidity
induced by McAbs against isotypic and idiotypic determinants of IgM from patients with leukemia was studied as well. The expression
of the corresponding isotypic and idiotypic determinants of IgM on the cell membrane was determined. The results show that
the membrane fluidity of leukemic cell lines is remarkably higher than that of tonsillar cells from healthy persons, and McAbs
against isotypic determinants of leukemic IgM can enhance the membrane fluidity of all kinds of cells mentioned above. However,
the anti-idiotypic monoclonal antibody increased only the membrane fluidity of leukemic cell lines. These results indicated
that there was a close relationship between the effect of McAbs on cell membrane fluidity and the expression of corresponding
isotypic and idiotypic determinants of IgM on the cell membrane. 相似文献
100.
Clonal deletion and anergy are two major mechanisms of self-tolerance. However, the molecular mechanisms underlying clonal deletion and anergy, as well as the threshold of TCR affinity/avidity required for these processes, are not known. Expression of the V beta 8.1 TCR correlates with the reactivity of the T cells to the minor lymphocyte stimulating locus-1a (Mls-1a) and T cells expressing this TCR are deleted in the thymus of Mls-1a mice. Similarly, in TCR V beta 8.1 transgenic mice, the number of CD4+CD8-T cells is reduced in Mls-1a mice. However, small numbers of CD4+CD8-T cells remain in the periphery of adult Mls-1a transgenic mice. We have generated T cell clones from TCR V beta 8.1 transgenic mice by stimulation of lymph node T cells with C57BL/6 alloantigens. Interestingly, CD4+CD8-V beta 8.1+ clones isolated from the transgenic mice of Mls-1a background responded to the self-antigen Mls-1a, to which they did not respond in primary assay. Reactive patterns of the clones were compared with clones derived from Mls-1b mice. Proliferation and cytokine production of the clones from Mls-1a mice to the self-antigen Mls-1a were generally reduced when compared with clones from Mls-1b mice. More importantly, T cell clones from Mls-1a mice required more Mls-1a antigen for their activation, and were more susceptible to the inhibitory effects of anti-CD4 antibody on the proliferative responses to Mls-1a than those from Mls-1b mice. These results suggest that the T cell receptor on clones derived from Mls-1a mice have functional but reduced affinity/avidity for self-antigen Mls-1a. 相似文献