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251.
The p38 mitogen-activated protein kinase pathway regulates interleukin-6 synthesis in response to tumor necrosis factor in osteoblasts 总被引:2,自引:0,他引:2
252.
Liu KJ Atten MJ Lichtor T Cho MJ Hawkins D Panizales E Busker J Stone J Donahue PE 《The American surgeon》2001,67(3):215-9; discussion 219-20
Serum amylase and lipase elevation has been observed in trauma patients and patients with traumatic intracranial bleeding. However, the causes of this elevation have not been clearly elucidated. A further question remains as to whether other intracranial events are associated with such enzyme elevation as well. We retrospectively reviewed 75 patients consecutively admitted to Cook County Hospital Neurosurgical Intensive Care Unit over a 3-month period for trauma, infection, tumor, or other space-occupying lesions with an unstable condition or neurological deficit. Eleven patients (15%) had elevated amylase and lipase levels. The patients were divided into two groups: Group I (n = 64) had normal and Group II (n = 11) had raised amylase and lipase levels [amylase 402 +/- 444 U/L with normal < or = 125 U/L and lipase 474 +/- 313 U/L with normal < or = 55 U/L]. All Group II patients suffered an intracranial event. Twenty-four Group I (38%) and 10 Group II (91%) patients required craniotomy (P < 0.01). No patients had clinical or radiographic evidence of pancreatitis. In summary, intracranial events are associated with serum amylase and lipase elevation probably through centrally activated pathways. Because of the lack of diagnostic value, routine pancreatic enzyme monitoring should not be performed in this patient population. 相似文献
253.
Rhee YG Cho NS 《Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.]》2007,16(2):188-192
Humeral avulsion of the glenohumeral ligament (HAGL) is a rare lesion. The purpose of this study was to analyze the clinical manifestations of HAGL lesions in patients who underwent operative treatment for anterior shoulder instability. Six patients with HAGL lesions were studied. Four patients had an HAGL lesion associated with a Bankart lesion, and two had an isolated HAGL lesion. The range of motion at final follow-up showed a loss of 1 degree in forward flexion and of 15 degrees in external rotation. During an operation to treat anterior shoulder instability, a thorough examination for not only Bankart lesions but also other associated lesions, including an HAGL lesion, should be considered to lower the risk of redislocation. In repairing an HAGL lesion, the surgeon should keep in mind the possibility of a postoperative loss of external rotation and follow an active rehabilitation protocol to obtain successful results. 相似文献
254.
255.
256.
Cho TJ Kim JA Chung CY Yoo WJ Gerstenfeld LC Einhorn TA Choi IH 《Calcified tissue international》2007,80(3):192-200
Distraction osteogenesis is a special form of bone healing in which well-controlled distraction stresses and consequent tensile
strains within callus tissue induce very efficient new bone formation. Proinflammatory cytokines are involved during the early
phase of fracture healing and callus remodeling. Temporal expression patterns of proinflammatory cytokines were assessed in
Sprague-Dawley rat tibial models of distraction osteogenesis and acute lengthening, and only interleukin-6 (IL-6) was found
to be specifically induced during the distraction phase. IL-6 immunoreactivity was detected not only in hemopoietic cells
and osteoblasts but also in the spindle-shaped cells of the fibrous interzone, where most of the tensile strains are concentrated.
In vitro study revealed that IL-6 did not affect the proliferation of C3H10T1/2 cells, mouse bone marrow stromal cells (MSCs), or
MC3T3-E1 cells; but its blocking antibody reduced the proliferation of C3H10T1/2 cells and MSCs. The mRNA expression of COL1A1
and osteopontin were not changed by IL-6 or its blocking antibody, but the alkaline phosphatase activities of MC3T3-E1 cells
were increased by IL-6 and decreased by its blocking antibody. These findings indicate that IL-6 is a proinflammatory cytokine
that responds to tensile strain during distraction osteogenesis. IL-6 negatively affects the proliferation of primitive mesenchymal
cells, whereas the differentiation of more mature osteoblastic lineage cells is enhanced by IL-6 in vitro. IL-6 appears to be one of the cytokines involved in the complex network of signal cascades evoked during distraction osteogenesis
and may differentially affect immature and mature osteoblastic lineage cells. 相似文献
257.
258.
Kwan Chang Kim Kwang Ree Cho Yong-Jin Kim Dae-Won Sohn Ki-Bong Kim 《European journal of cardio-thoracic surgery》2007,31(2):261-266
OBJECTIVE: We evaluated the long-term results of the Cox-Maze III procedure (CM-III) for persistent atrial fibrillation (AF) associated with rheumatic mitral valve (MV) disease. METHODS: We analyzed 127 patients who underwent the CM-III combined with a rheumatic MV procedure between 1994 and 2004. In-hospital mortalities were excluded from the study. RESULTS: There were 10 late deaths and the mean follow-up duration was 7.1+/-2.8 years (range, 13 months to 11.5 years). Normal sinus rhythm was restored in 88.2% (112/127) after the CM-III. Right atrial contractility was demonstrable in 100% (112/112) and left atrial contractility in 68.8% (77/112) of the patients restored to sinus rhythm. Fifteen patients never regained sinus rhythm after the CM-III (AF treatment failure). Permanent pacemakers were implanted in 4.7% (6/127) of the patients during the follow-up. Late recurrence of AF developed in 34 of 112 patients at 44+/-27 months postoperatively, and sinus rhythm was restored in 29 of 34 patients by administration of an antiarrhythmic medication. Independent risk factors for late AF recurrence were longer duration of AF (>60 months) (odds ratio (OR)=2.758, p=0.025), increased left atrial size (OR=1.113, p=0.004). Freedom from AF recurrence was 93% at 1-year, 82% at 3 years, 71% at 5 years, and 63% at 7 years. Risk factors for AF treatment failure were longer duration of AF (>60 months) (p<0.001) and increased patient age (p=0.030). A higher prevalence of significant late tricuspid regurgitation was observed in patients with AF treatment failure and those with late AF recurrence. CONCLUSIONS: The CM-III for persistent AF associated with rheumatic MV disease demonstrated a progressively decreased cure rate during the follow-up period. Early surgical therapy, aggressive left atrial reduction, and correction of tricuspid regurgitation at the time of surgery may increase the long-term success rate. 相似文献
259.
Between July 1986 and March 2006, 102 patients underwent an operation for acute scrotum. Median age was 12.0 years old (range 0-51). Post-operative diagnosis revealed 50 cases (49%) of spermatic cord torsion, 29 cases (28%) of epididymal appendix torsion, and 13 cases (13%) of acute epididymitis. Spermatic cord torsion was most frequent in the age between 0 and 5, and 11 and 20, while epididymal appendix torsion was most frequent between 6 and 10. Moreover, acute epididymitis was most frequently seen in the age over 20. There were no apparent differences in the clinical symptoms such as scrotal pain, scrotal swelling, and abdominal pain. In the physical examinations, pyuria was the only finding to indicate acute epididymitis. In case of spermatic cord torsion, 'golden time' is defined as the time from onset to operation when testicular function can be expected for preservation. In this study golden time was defined as 8 hours because the testes was preserved in all 23 patients receiving the operation within 8 hours, but in only 10 (37%) out of 27 patients receiving the operation after 8 hours. Moreover, the operation within 24 hours saved the testes in approximately 90% of the patients. In patients with acute scrotum, emergency operation should be performed as speedily as possible for preservation of testicular function. 相似文献
260.
Jeon DH Oh K Oh BC Nam DH Kim CH Park HB Cho J Lee JR Lee DS Lee G 《Xenotransplantation》2007,14(3):236-242
BACKGROUND: Effective intervention achieved by manipulating cell-mediated xenogeneic immune responses would critically increase the clinical feasibility of xenotransplantation as immediate hyperacute rejections become controllable through genetic modulations of donor organs. Endogenous negative regulatory signals like the programmed death 1 (PD-1)-programmed death ligand 1 (PD-L1) system are candidate targets for the control of cell-mediated xenogeneic immune response. METHODS: A porcine PD-L1 molecule was cloned using RACE (rapid amplification of cDNA ends) technology based on the human PD-L1 sequence. The functional effects of cloned porcine PD-L1 were tested on human CD4(+) T cell activation using porcine PD-L1-transfected bystander cells. Cellular proliferation was monitored by [3H] thymidine incorporation, and human T cell apoptosis was measured by flow cytometry. RESULTS: Porcine PD-L1 (GenBank accession number AY837780) was found to have 73.8% sequence homology with human PD-L1 and to contain two immunoglobulin domains in its extracellular region. Moreover, porcine PD-L1 expressed on Chinese hamster ovary (CHO) cells inhibited human CD4(+) T cell proliferation stimulated with anti-CD3 only or anti-CD3 plus anti-CD28. Percentages of apoptotic activated human T cells increased by over 30% in the presence of porcine PD-L1/CHO cells, and the addition of recombinant human PD-1-Fc fusion proteins during human T cell activation reversed the inhibitory effects of porcine PD-L1. CONCLUSIONS: Cloned porcine PD-L1 showed high sequence homology with human PD-L1 and a similar molecular structure. Moreover, porcine PD-L1 inhibited human CD4(+) T cell activation in human PD-1-dependent manner, and this involved activated T cell apoptosis. The authors suggest that PD-1-PD-L1 might play an important endogenous immune regulatory role during xenogeneic transplantation, and that the effective application of this system would improve transplanted xenogeneic organ survival. 相似文献